JP2003294060A - Reversed input breaking clutch - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To make rotation of an output side member 2 smooth by suppressing occurrence of a stick-slip phenomenon in which the output-side member 2 repeats locking and rotation, even in the case where the output-side member 2 can rotate at a higher speed than that of an input-side member 1, in the same direction as the input-side member 1 during rotation of the input-side member 1 of a reversed input breaking clutch. <P>SOLUTION: The reversed input breaking clutch is provided with a friction giving means 10 which applies frictional resistance on the output-side member 2 during rotation of the output-side member 2 with respect to a stationary side member 3. The friction giving means 10 is disposed outside a clutch body. In addition, the friction giving means 10 is arranged so as to extend over the stationary side member 3 and the output-side member 2, and has a frictional member 10b made of resin which comes into frictional contact with the outer peripheral surface of the stationary side member 3. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reverse input cutoff clutch having a function of transmitting an input torque from an input side to an output side while locking a reverse input torque from an output side so as not to recirculate to the input side.

[0002] [Detailed Description of the Invention]

[0003]

2. Description of the Related Art For example, in an apparatus which transmits an input torque from a drive source to an output side mechanism to perform a required operation, there is a function of holding the output side mechanism so that its position does not change when the drive source is stopped. It may be required, as an example,
A lifting device for vertically moving various objects to be lifted is generally known.

In this type of lifting device, a drive motor or manual input torque in the forward or reverse direction is input to the lifting mechanism on the output side to vertically move the object to be lifted. When the input of the drive motor or the manual torque is stopped during the movement, it is necessary to prevent the lifted body from lowering by its own weight and hold the lifted body at its height position. .

[0005]

SUMMARY OF THE INVENTION For the purpose of giving this type of lifting device the above-mentioned function, the applicant of the present invention has proposed that the input side member in the previous patent application (Japanese Patent Application No. 2001-65239). The input torque from the output side member is transmitted to the output side member, but the reverse input torque that returns from the output side member to the input side member is locked by the output side member and is not transmitted to the input side member. An input cutoff clutch was proposed.

Specifically, an input side member to which the rotational torque is input, an output side member to which the rotational torque is output, a stationary side member to which rotation is restricted, and a stationary side member and the output side member are provided. Lock means for locking the output side member and the stationary side member against reverse input torque from the output side member, and lock means for the input torque from the input side member provided on the input side member. The lock release means for releasing the locked state and the input torque from the input side member are transmitted to the output side member when the lock state is provided between the input side member and the output side member and the lock state by the lock means is released. Torque transmitting means for

In the lifting device having the reverse input cut-off clutch, the lock by the lock means is released by inputting the rotational torque in the forward and reverse directions to the input side member by the drive motor or manually. The rotation torque is transmitted to the output side member via the torque transmission means, and as a result, the lifting device moves the lifted body up and down. On the other hand, if the input of the rotational torque to the input side member is stopped while the lifting device is moving up and down, the reverse input torque returns from the output side member due to the weight of the lifted body. However, against this reverse input torque, the output side member is locked with the stationary side member by the action of the locking means, and as a result, the lifted body does not descend due to its own weight and its height position is increased. Held in.

By the way, according to the elevating device having such a structure, while the rotational torque is input to the input side member and the object to be lifted is lowered, for example, the rotation direction of the input side member and the object to be lifted up and down. The rotation direction of the output side member that causes the reverse input torque to flow back due to the weight of the body is the same direction. In this case, when a rotational force is generated by the weight of the lifted body and the rotation speed of the output side member becomes higher than the rotation speed of the input side member, the output side member receives the reverse input torque to cause the output side member to rotate. The state where the member is locked, the state where the lock is released by the input torque from the input side member under this state, and the input torque from the input side member is transmitted to the output side member under this unlocked state The state of being repeated causes a situation that it appears repeatedly.

Due to this, the output side member may cause a so-called stick-slip phenomenon in which the output side member repeatedly locks and rotates, and there is a fear that torque transmission is performed in a state where a jerky or chattering feeling occurs. In addition, there is a risk that smooth lowering of the lifted body may be hindered, and an abnormal noise may be generated or the operation feeling may be deteriorated in the case of manual operation.

The present invention has been made in view of the above circumstances, and when the input side member of the reverse input cut-off clutch having the above-described structure is rotated, the speed is higher in the same direction as the input side member. Even if the rotation can be imparted to the output side member, it is a technical object to prevent the occurrence of the stick-slip phenomenon in which the output side member repeatedly locks and rotates, and to smooth the rotation of the output side member. To do.

[0011]

In order to solve the above technical problems, the present invention is directed to an input side member to which a rotation torque is input, an output side member to which a rotation torque is output, and a stationary member in which rotation is restricted. A side member, locking means provided between the stationary side member and the output side member, for locking the output side member and the stationary side member against a reverse input torque from the output side member; Lock release means provided on the input side member for releasing the locked state of the lock means against the input torque from the input side member; and the lock release means provided between the input side member and the output side member. A reverse input cutoff clutch comprising: torque transmitting means for transmitting the input torque from the input side member to the output side member when the locked state by the means is released,
It is characterized in that a friction imparting means is provided for applying a frictional resistance to the output side member when the output side member is rotated with respect to the stationary side member.

According to this structure, when the rotational torque is input to the input side member in the stopped state, first,
The locked state by the lock means is released by the lock release means, and in that state, the rotational torque from the input side member is transmitted to the output side member via the torque transmitting means. On the other hand, the reverse input torque from the output side member is locked between the output side member and the stationary side member via the locking means. Therefore,
A function is provided in which the input torque from the input side is transmitted to the output side and the reverse input torque from the output side is not returned to the input side.

In this case, when the output side member is rotating with respect to the stationary side member, a frictional resistance acts on the output side member due to the operation of the friction imparting means, so that a rotational torque is applied to the input side member. Even when the rotation speed of the output side member becomes higher than the rotation speed of the input side member during input, and the output side member can be locked due to reverse input from the output side member, A braking force due to frictional resistance acts on the member, and its rotation is suppressed. As a result, the output side member is prevented from being locked, so that it becomes difficult for the output side member to be repeatedly locked, unlocked, and transmitted with torque from the input side member. Generation is suppressed, and the rotation of the output side member is smoothed.

In the above structure, the friction applying means is
It is preferably arranged outside the clutch body, in other words, externally attached. With this configuration,
It is possible to make the clutch body of the reverse input cutoff clutch compact and to use the reverse input cutoff clutch for applications in which friction imparting means is unnecessary, for example, when the weight of the lifted body in the above-mentioned lifting device does not matter. The reverse input cut-off clutch used in the above and the clutch body can be shared, which is advantageous in terms of mass production and cost reduction.

In the above structure, the friction applying means is
It is preferable that the stationary side member and the output side member are arranged so as to straddle the stationary side member and the output side member. That is, this friction imparting means is
Although it is possible to dispose the fixing member other than the constituent elements of the reverse input cutoff clutch and the output side member, the stationary side member and the output side member, which are the constituent elements of the reverse input cutoff clutch, are thus arranged. By arranging them straddling, unitization and downsizing are promoted, and transportation, carrying and handling are convenient.

In the above structure, the friction applying means is
It is preferable that the output side member can rotate integrally with the output side member and can relatively rotate in frictional contact with the outer peripheral surface of the stationary side member. With this configuration, the frictional resistance generated by the frictional contact with the outer peripheral surface of the stationary side member acts on the output side member, so that the output side member is not worn due to friction and contributes to the torque output. It is possible to effectively suppress the early deterioration of the important member and the early inhibition of the clutch function.

In the above structure, the friction applying means is
It is preferable to provide a resin friction member that makes frictional contact with the outer peripheral surface of the stationary member. That is, it is possible to bring a metal member into frictional contact with the outer peripheral surface of the stationary member, but if this is done, abnormal noise (metal sound) is generated or wear occurs on the stationary member, Further, although there is a possibility that sufficient frictional resistance cannot be obtained, the probability of occurrence of such a problem becomes extremely low in the case of a resin friction member.

In the above structure, it is preferable that the resin friction member is held by a metal spring member integrally rotatably attached to the output side member so as not to rotate relative to each other. With this configuration, the desired frictional resistance can be obtained only by pressing the resin friction member against the outer peripheral surface of the stationary member by the spring force of the metal spring member. It is possible to simplify, reduce the number of parts, and further reduce the price.

The reverse input cutoff clutch having the above structure is preferably used for a lifting device. That is, in the lifting device including the reverse input cutoff clutch of this type, as described above, the rotational force is generated by the weight of the lifted body, and the rotation speed of the output side member is higher than that of the input side member. When it becomes large, the frequency of occurrence of stick-slip phenomenon is extremely high, but the effect of the above-mentioned friction imparting means can remarkably obtain the avoidance effect against such a defect.

Here, the above-mentioned "locking means" gives a rotation restraining force by a wedge engaging force, a concave and convex engaging force, a frictional force, a magnetic force, an electromagnetic force, a fluid pressure, a fluid viscous resistance force, a fine particle medium and the like. However, in view of simplification of the structure and control mechanism, smooth operation, cost, etc., it is preferable to apply the rotation restraining force by the wedge engaging force. Specifically, a wedge gap is formed between the output side member and the stationary side member, and the engaging element is wedge-engaged / disengaged with respect to the wedge gap,
It is better to have a configuration that switches between locking and idling. Further, in this configuration, a cam surface for forming a wedge gap is provided on the output side member or the stationary side member (roller as an engaging element,
Use a circular cross section such as a ball. ), A structure in which a cam surface for forming a wedge gap is provided on the engaging element (a sprag or the like is used as the engaging element).

Further, the above-mentioned "locking means" forms a wedge gap between the circumferential surface provided on the stationary side member and the circumferential surface provided on the output side member in both forward and reverse rotation directions. A cam surface, a pair of engagement elements interposed between the cam surface and the circumferential surface,
An elastic member that presses each of the pair of engagement elements in the direction of the wedge gap may be provided. Further, the above-mentioned "lock releasing means" can be an engaging element that selectively engages with one of the pair of engaging elements and presses it in the direction opposite to the direction of the wedge gap. . Further, the above-mentioned "torque transmitting means" may be engaging elements in the rotational direction provided on the input side member and the output side member. Then, at the neutral position of the “lock releasing means” and the “torque transmitting means”, the rotational gap δ1 between the engaging element and the engaging element of the “lock releasing means” and the “torque transmitting means”.
The rotational gap δ2 between the engaging elements may have a relationship of δ1 <δ2.

According to the above construction, when a reverse input torque in one direction is input to the output side member, one of the pair of engaging elements is wedge-engaged with the wedge gap in that direction to output the output. When the side member is locked in one direction with respect to the stationary member and the reverse input torque in the other direction is input to the output member, the other of the pair of engaging elements is wedge-engaged with the wedge gap in that direction. do it,
Lock the output member in the other direction with respect to the stationary member.
Therefore, the output side member is locked in both the forward and reverse rotation directions with respect to the stationary side member via the pair of engaging elements. On the other hand, when the input torque is input to the input side member, first, the engagement element serving as the lock release means provided in the input side member forms the wedge gap in the direction of the input torque among the pair of engagement elements. The wedge-engaging element is pressed in the direction opposite to the direction of the wedge gap to disengage it from the wedge gap. As a result, the locked state of the output side member is released in the direction of the input torque. Next, in the state where the output side member is unlocked, the engaging elements in the rotational direction as the torque transmitting means provided on the input side member and the output side member engage with each other. As a result, the input torque input to the input side member is transmitted through the route of the input side member → the torque transmitting means (engaging element in the rotation direction) → the output side member, and the output side member rotates.

Further, in the neutral position of the lock releasing means and the torque transmitting means, the rotational gap δ1 between the engaging element and the engaging element of the lock releasing means and the rotational gap δ2 between the engaging elements of the torque transmitting means. By setting the relations δ1 <δ2, it is possible to sequentially and reliably perform the unlocking by the unlocking means and the torque transmission by the torque transmitting means.

[0024]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

1 and 2 show the overall structure of a reverse input cutoff clutch according to an embodiment of the present invention. The clutch of this embodiment includes the input side member 1 to which torque is input.
An output side member 2 for outputting torque, a stationary side member 3 for which rotation is restricted, a fixed side plate 4 fixed to the stationary side member 3, a locking means, an unlocking means, and a torque transmitting means described later. It consists of and as the main elements.

The input-side member 1 has an annular plate-like base plate 1a having a boss portion 1x to which a shaft hole forming body 5 is fitted and fixed at the center in the radial direction, and an axial direction from the outer periphery of the base plate portion 1a. A plurality of (for example, six) column portions 1b continuously extending in one direction (inward direction of the clutch), and a plurality of protrusion portions formed in the axial direction from the middle of the boss portion 1x of the substrate portion 1a and the column portion 1b. It is mainly composed of (for example, 6 pairs) protrusions 1c. The protrusion 1c has a cylindrical shape in this embodiment. In addition, the shaft hole forming body 5
The shaft hole 5a has two flat surfaces 5b, and the flat surfaces of the flat surface formed on the connecting portion of the input shaft and the flat surfaces 5b of the shaft hole 5a are fitted to each other by the flat fitting, whereby the input shaft and the input side are The member 1 is connected so as not to rotate relative to it.

The pillar portion 1b and the protruding portion 1c are arranged at equal intervals around the circumference, and the positions of the pillar portion 1b and the protruding portion 1c are displaced from each other in the circumferential direction. The protrusion 1c is located at an intermediate position between the pillars 1b adjacent to each other in the circumferential direction. A pocket 7 that is a space that is open toward one side in the axial direction is formed between the pillar portions 1b that are adjacent to each other in the circumferential direction, and a pair of rollers 6 is arranged in each pocket 7 (for details, see See below).

The output side member 2 has a flange portion 2a extending in a radial direction, an output shaft portion 2b continuously extending in one axial direction from an inner circumference of the flange portion 2a, and an outer circumference of the flange portion 2a. And a large-diameter portion 2c that continuously extends from the other to the other in the axial direction, and a plurality of (for example, six) recesses 2d are formed on the other side surface portion in the axial direction of the large-diameter portion 2c. .
Then, the plurality of projections 1c of the input side member 1 are loosely fitted in the plurality of recesses 2d with predetermined rotational gaps.

At the shaft end portion of the output shaft portion 2b, for example, 1
One flat surface portion 2e is provided {see FIG. 1 (b)}, and this shaft end portion is connected to a rotating member of an output side mechanism or device (not shown), and The output shaft portion 2b and the rotating member are connected to each other so as not to rotate relative to each other by the plane fitting with the flat surface portion formed on the rotating member. Further, the flat surface portion 2e of the shaft end portion of the output shaft portion 2b is also used for mounting the friction imparting means 10 described later.

In the example shown in FIG. 2, the large-diameter portion 2c of the output side member 2 has a polygonal shape (for example, a regular hexagonal shape), and the outer circumference of each side is a cam surface 2f, and the 6
Two cam surfaces 2f are arranged on the outer circumference of the large diameter portion 2c at equal intervals in the circumferential direction.

The stationary side member 3 has an annular plate-like side plate portion 3b having a cylindrical portion 3a continuously extending in one axial direction at the center of the radial direction, and an axial direction from the outer periphery of the side plate portion 3b. The main part is composed of a large-diameter covering portion 3c extending to the other side, and a flange portion 3e projecting outward from one end of the large-diameter covering portion 3c.

Between the inner peripheral surface of the cylindrical portion 3a of the stationary side member 3 and the outer peripheral surface of the axially intermediate portion (non-formation portion of the flat surface portion 2e) of the output shaft portion 2b of the output side member 2. A radial bearing member 8 is provided.

Further, on the inner circumference of the large diameter covering portion 3c of the stationary side member 3, a circle is formed which faces the cam surface 2f of the output side member 2 in the radial direction and forms a wedge gap in both the forward and reverse rotation directions. A peripheral surface 3f is provided.

Further, a plurality of (for example, six) rectangular notch portions 3g are formed in the flange portion 3e of the stationary side member 3 at equal intervals in the circumferential direction, and these notch portions 3g (one The total of the three notches 3g) fits with the caulking portion 4c of the fixed side plate 4 described later. The other cutouts 3g are provided to avoid interference with the mounting bolts mounted on the fixed side plate 4.

The fixed side plate 4 has a plurality of bracket portions 4b (for example, three directions) protruding from the outer periphery of the base side plate portion 4a toward the outer diameter side, and a non-protruding portion of the base side plate portion 4a in one axial direction. The main components are a plurality of (for example, three) caulking portions 4c protruding toward each other and an insertion hole 4d formed in the central portion of the base side plate portion 4a. Then, the input shaft connected to the input side member 1 is inserted into the insertion hole 4d. Further, each bracket portion 4b is formed with a through hole 4e, and a mounting bolt is inserted into each of these through holes 4e.

Each caulking portion 4c is provided with a pair of claws 4f which are formed at equal intervals in the circumferential direction and are bifurcated (see FIG. 2). Then, the caulking portion 4c is fitted into the cutout portion 3g of the stationary side member 3, the pair of claws 4f are folded back in opposite directions in the circumferential direction, and caulked to the collar portion 3e of the stationary side member 3, The stationary side member 3 and the fixed side plate 4 are coupled to each other in an axially and rotationally immovable manner.

As shown in FIG. 2, between the cam surface 2f of the output side member 2 and the circumferential surface 3f of the stationary side member 3, respectively,
A pair (for example, a total of 6 pairs) of rollers 6 serving as engaging elements are arranged and housed in a pocket 7 formed between the pillar portions 1b of the input side member 1. Further, an elastic member (spring) 9 that separates the rollers 6 from each other is interposed between the pair of rollers 6. The elastic member 9 is, for example, a thin spring plate portion bent and formed into a U-shaped cross section or a U-shaped cross section, and one piece portion 9a facing each other abuts on one roller 6 and the other one. 9a is in contact with the other roller 6.

In this case, the cam surface 2f, the circumferential surface 3f, the pair of rollers 6, and the elastic member 9 constitute a locking means, and the pair of rollers 6 are located on both sides in the circumferential direction of the input side. The column portion 1b (engagement element) of the member 1 constitutes lock releasing means, and the projection 1c of the input side member 1 and the recess 2d of the output side member 2 into which the projection 1c is loosely fitted.
A torque transmitting means is constituted by and. Note that, for example, grease is filled in the space between the outer circumference of the output side member 2 and the inner circumference of the stationary side member 3, especially between the cam surface 2f and the circumferential surface 3f.

In addition to the above construction, this reverse input cutoff clutch is rotatable integrally with the output side member 2 and is in frictional contact with the outer peripheral surface of the large diameter covering portion 3c of the stationary side member 3. Relatively rotatable friction imparting means 10 is provided. The friction imparting means 10 is provided outside the clutch body composed of the above-described constituent elements 1 to 9, and is provided with a metal spring member 10a made of spring steel or the like and a resin friction member made of Duracon or the like. It is composed of a member 10b.

As shown in FIG. 3, the metal spring member 10a has an annular plate-like annular shape with a fitting hole 10c fitted in the output shaft portion 2b of the output side member 2 at the center in the radial direction. Base 10d,
A plurality of (for example, six) claw-shaped portions 10e extending in a crown shape from the outer circumference of the annular base portion 10d toward the other in the axial direction are integrally formed. The fitting hole 10c has a flat surface portion 10f corresponding to the flat surface portion 2b of the shaft end portion of the output shaft portion 2b. By flatly fitting both flat surface portions 2f, 10f, the metal spring member 10a. Are integrally and rotatably coupled to the output side member 2. Further, the claw-shaped portions 10e are formed at equal intervals in the circumferential direction, and the tips of the claw-shaped portions 10e are slightly bent toward the outer diameter side, and the bent portions 10g are made of resin. It serves as a pressing portion for the friction member 10b.

As shown in FIG. 4, the resin friction member 10b has a ring-shaped plate portion 10h and a plurality of (eg, six) extending from the outer periphery of the ring portion 10h toward the other axial direction.
The projecting piece portion 10i is integrally formed. The projecting piece portions 10i are formed at equal intervals in the circumferential direction, and the inner peripheral surface of each projecting piece portion 10i is an arc surface that makes frictional contact with the outer peripheral surface of the stationary side member 3, and Engagement recesses 10j with which the tips of the claw-shaped portions 10e of the metal spring members 10a are engaged are formed on the outer peripheral surface of each projecting piece 10i.
In addition, at the tip of each protrusion 10i of the resin friction member 10b,
A bent portion 10k that is slightly bent toward the outer diameter side is formed, and the bent portion 10k performs axial positioning of each claw-shaped portion 10e of the metal spring member 10a.

The annular plate-shaped ring portion 10h of the resin friction member 10b does not have to be continuous in the circumferential direction as described above. For example, as shown in FIG. The ring portions 10h may be formed intermittently at intervals.

As shown in FIG. 1 (a), the friction imparting means 10 having the above-mentioned structure is such that the metal spring member 10a is brought into contact with the stepped surface of the output shaft portion 2b of the output side member 2 and Output side member 2
The resin friction member 10
The inner peripheral surface of each protruding piece 10i of b is brought into contact with the outer peripheral surface of the stationary side member 3 and the ring portion 10h is brought into contact with the outer surface of the side plate portion 3b of the stationary side member 3 so that the outer periphery of each protruding piece 10i is engaged. By engaging the tips of the claw-shaped portions 10e of the metal spring member 10a with the fitting recesses 10j, they are externally attached to the clutch body. Under this condition,
By the spring force of each claw-shaped portion 10e of the metal spring member 10a, each protruding piece 10i of the resin friction member 10b is pressed against the outer peripheral surface of the stationary side member 3,

Next, the main operation of the reverse input cutoff clutch having the above structure will be described with reference to FIGS.

As shown in the enlarged view of FIG. 6, in the neutral position, the pair of rollers 6 are pressed by the elastic member 9 in the direction in which they are separated from each other, and the cam surface 2f and the circumferential surface 3f respectively.
Engages with the wedge gaps formed in the forward and reverse directions. At this time, there is a rotational gap δ1 between each column portion 1b of the input side member 1 and each roller 6. Further, between the concave portion 2d of the output side member 2 and the projection portion 1c of the input side member 1, there are rotational gaps δ2 in both the forward and reverse rotational directions. The rotational gap δ1 and the rotational gap δ2 are δ1 <
It has a relationship of δ2. The size of the rotational gap δ1 is, for example, 0 to 0.4 mm (0 to about the clutch axis).
The size of the rotational gap δ2 is, for example, 0.4 to 0.8 mm (1.
It is about 8 to 3.7 °).

In the state shown in FIG. 6, for example, the output side member 2
When a counterclockwise reverse input torque is input to, the counterclockwise (rotational rear) roller 6 wedge-engages with the wedge gap in that direction, and the output side member 2 moves in a clockwise direction with respect to the stationary side member 3. Locked in the direction. When a counterclockwise reverse input torque is input to the output side member 2, the roller 6 in the clockwise direction (rearward in the rotational direction) engages with the wedge gap in that direction, and the output side member 2 causes the stationary side member 3 to move. Is locked counterclockwise. Therefore, the reverse input torque from the output side member 2 is locked by the roller 6 in both forward and reverse rotation directions.

FIG. 7 shows an initial state in which an input torque (clockwise in the figure) is input to the input side member 1 and the input side member 1 starts to rotate clockwise in the figure. Since the gap in the rotation direction is set to δ1 <δ2, first, the counterclockwise (rearward in the rotation direction) column portion 1b of the input member 1 engages with the roller 6 in that direction (rearward in the rotation direction). This is pressed in the clockwise direction (forward in the rotational direction) against the elastic force of the elastic member 9. As a result, the roller 6 in the counterclockwise direction (rearward in the rotational direction) is released from the wedge gap in that direction, and the locked state of the output side member 2 is released {the roller 6 in the clockwise direction (forward in the rotational direction) is released. , Does not engage with the wedge gap in that direction. }. Therefore, the output side member 2 can be rotated clockwise.

When the input side member 1 is further rotated clockwise, the projection 1c of the input side member 1 engages with the recess 2d of the output side member 2 in the clockwise direction as shown in FIG. This allows
The clockwise input torque from the input side member 1 is transmitted to the output side member 2 via the engaging portion between the protrusion 1c and the recess 2d,
The output side member 2 rotates clockwise. When a counterclockwise input torque is input to the input side member 1, the output side member 2 rotates counterclockwise by the operation opposite to the above. Therefore, the input torque from the input side member 1 in both the normal and reverse rotation directions is transmitted to the output side member 2 via the projection 1c and the recess 2d as the torque transmission means, and the output side member 2 is rotated in the forward and reverse rotation directions. Turn to. When the input torque from the input side member 1 disappears, the elastic restoring force of the elastic member 9 restores the neutral position shown in FIG.

In this case, when the above-mentioned reverse input cutoff clutch is used in an elevating device for vertically moving an object to be lifted, the rotational torque generated by the drive motor or manually is input to the input side member 1 as the input torque. On the other hand, the rotation torque generated by the weight of the lifted body is input to the output side member 2 as the reverse input torque. Then, when the force for rotating the input side member is larger than the force for rotating the output side member in the same direction, even if the output side member 2 is in a freely rotatable state, The reverse input cutoff clutch operates as described above.

On the other hand, in the state shown in FIG. 8, the rotation speed r2 of the output side member 2 can be higher than the rotation speed r1 of the input side member 1 due to the weight of the lifted body. In such a case, if the output side member 2 is in a freely rotatable state, a reverse input from the output side member 2 shifts from the state shown in FIG. 7 to the state shown in FIG. The output side member 2 will be locked. Immediately after this, the state shown in FIG. 6 again shifts to the state shown in FIG. 7, torque is transmitted to the output side member 2, and the output side member 2 starts to rotate again, that is, a stick-slip phenomenon. Occurs.

However, in this reverse input cutoff clutch, the friction applying means which can rotate integrally with the output side member 2 is provided.
Since the metal spring member 10a of 10 and the resin friction member 10b rotatable integrally with the metal spring member 10a are in frictional contact with the stationary member 3, frictional resistance is imparted to the output member 2 during its rotation. That is, in the state shown in FIG. 8, the output side member 2
The frictional resistance necessary to prevent the rotational speed r2 of the input side member 1 from exceeding the rotational speed r1 of the input side member 1 is imparted. Therefore, the situation in which the output side member 2 is locked by the reverse input from the output side member 2 does not occur, and for example, when the lifted body is lowered in the lifting device, the reverse input cutoff clutch continues the state shown in FIG. This can be maintained, and the rotation of the output side member 2 can be smoothed.

[0052]

As described above, according to the reverse input cut-off clutch according to the present invention, the friction applying means for applying frictional resistance to the output side member when the output side member is rotated with respect to the stationary side member is provided. Even if the rotational speed of the member can be higher than the rotational speed of the input side member, the braking force due to the frictional resistance acts on the output side member and the rotation thereof is suppressed. Therefore, the problem that the output member is locked is avoided, and the stick-slip phenomenon in which locking and rotation are repeatedly applied to the output member is less likely to occur, and as a result, the rotation of the output member is smooth. Be converted.

By disposing the friction applying means outside the clutch main body, the clutch main body of the reverse input breaking clutch can be made compact, and the reverse input breaking clutch used in applications where the friction applying means is unnecessary. And the clutch body can be shared, which is advantageous for mass production and cost reduction.

Further, by disposing the friction applying means across the stationary side member and the output side member, unitization and downsizing can be further promoted, and transportation, portability and handling are convenient. Planned.

Further, the friction applying means can rotate integrally with the output side member, and can rotate relative to the outer peripheral surface of the stationary side member by friction so that the output side member is not worn due to friction. It is possible to effectively suppress the early deterioration of important members related to the torque output and the early inhibition of the clutch function.

Further, since the friction applying means is provided with the resin-made friction member that makes frictional contact with the outer peripheral surface of the stationary member, abnormal noise (metal sound) is generated, the stationary member is worn, and further friction is caused. Problems such as insufficient resistance can be effectively avoided.

Further, by holding the resin friction member on the metal spring member integrally rotatably attached to the output side member so that the resin friction member cannot rotate relative to the output side member, only the spring force of the metal spring member allows the resin friction member to rotate. Since it is possible to obtain the desired frictional resistance by pressing against the outer peripheral surface of the stationary member, it is possible to simplify the structure of the friction applying means, reduce the number of parts, and further reduce the cost.

By using this reverse input cut-off clutch in the lifting device, the rotation speed of the output side member becomes higher than the rotation speed of the input side member due to the own weight of the lifted body, and the stick-slip phenomenon occurs. It is possible to appropriately avoid the problem that occurs.

[Brief description of drawings]

FIG. 1 is a vertical sectional side view of a reverse input breaking clutch according to an embodiment of the present invention {FIG. 1 (a): BB sectional view of FIG. 2}, an X direction arrow view of an output shaft portion {FIG. 1 ( b)}.

FIG. 2 is a vertical sectional front view showing a reverse input cutoff clutch according to an embodiment of the present invention {a sectional view taken along line AA of FIG. 1 (a)}.

FIG. 3 is a vertical sectional side view showing a metal spring member that is a component of the friction imparting means {FIG. 3 (a)}, and a front view thereof.
(B)}.

FIG. 4 is a front view (FIG. 4 (a)) showing a resin friction member which is a constituent element of the friction imparting means, and a vertical sectional side view thereof (FIG. 4).
(B): It is CC sectional drawing of FIG.4 (d)}, the principal part top view {FIG.4 (c)}, and its rear view {FIG.4 (d)}.

5 is a front view showing another example of a resin-made friction member that is a component of the friction imparting means {FIG. 5 (a)}, and a longitudinal side view thereof {FIG. 5 (b): D in FIG. 5 (c). -D sectional view}, and its rear view {FIG.5 (c)}.

FIG. 6 is a partially enlarged vertical sectional front view illustrating the operation of the reverse input cutoff clutch according to the embodiment of the present invention (neutral position).

FIG. 7 is a partially enlarged vertical sectional front view for explaining the action of the reverse input cutoff clutch according to the embodiment of the present invention (when unlocked).

FIG. 8 is a partially enlarged vertical sectional front view for explaining the operation of the reverse input cutoff clutch according to the embodiment of the present invention (during torque transmission).

[Explanation of symbols]

1 Input side member 2 Output side member 3 stationary member 4 Fixed side plate 6 roller 7 Elastic member 10 Friction applying means 10a Metal spring member 10b Resin friction member

[Procedure amendment]

[Submission date] November 5, 2002 (2002.11.
5)

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be amended] Detailed explanation of the invention

[Correction method] Change

[Correction content]

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reverse input cutoff clutch having a function of transmitting an input torque from an input side to an output side while locking a reverse input torque from an output side so as not to recirculate to the input side.

[0002]

2. Description of the Related Art For example, in an apparatus which transmits an input torque from a drive source to an output side mechanism to perform a required operation, there is a function of holding the output side mechanism so that its position does not change when the drive source is stopped. It may be required, as an example,
A lifting device for vertically moving various objects to be lifted is generally known.

In this type of elevating device, a drive motor or manual input torque in the forward or reverse direction is input to the elevating mechanism on the output side to vertically move the object to be lifted. When the input of the drive motor or the manual torque is stopped during the movement, it is necessary to prevent the lifted body from lowering by its own weight and hold the lifted body at its height position. .

[0004]

SUMMARY OF THE INVENTION For the purpose of giving this type of lifting device the above-mentioned function, the applicant of the present invention has proposed that the input side member in the previous patent application (Japanese Patent Application No. 2001-65239). The input torque from the output side member is transmitted to the output side member, but the reverse input torque that returns from the output side member to the input side member is locked by the output side member and is not transmitted to the input side member. An input cutoff clutch was proposed.

Specifically, the input side member to which the rotational torque is input, the output side member to which the rotational torque is output, the stationary side member to which the rotation is restricted, and the stationary side member and the output side member are provided. Lock means for locking the output side member and the stationary side member against reverse input torque from the output side member, and lock means for the input torque from the input side member provided on the input side member. The lock release means for releasing the locked state and the input torque from the input side member are transmitted to the output side member when the lock state is provided between the input side member and the output side member and the lock state by the lock means is released. Torque transmitting means for

In the lifting device having the reverse input cut-off clutch, the lock by the lock means is released by inputting the rotational torque in the forward and reverse directions to the input side member by the drive motor or manually. The rotation torque is transmitted to the output side member via the torque transmission means, and as a result, the lifting device moves the lifted body up and down. On the other hand, if the input of the rotational torque to the input side member is stopped while the lifting device is moving up and down, the reverse input torque returns from the output side member due to the weight of the lifted body. However, against this reverse input torque, the output side member is locked with the stationary side member by the action of the locking means, and as a result, the lifted body does not descend due to its own weight and its height position is increased. Held in.

By the way, according to the elevating device having such a configuration, while the rotating torque is input to the input side member and the object to be lifted is lowered, for example, the rotation direction of the input side member and the object to be lifted or lowered. The rotation direction of the output side member that causes the reverse input torque to flow back due to the weight of the body is the same direction. In this case, when a rotational force is generated by the weight of the lifted body and the rotation speed of the output side member becomes higher than the rotation speed of the input side member, the output side member receives the reverse input torque to cause the output side member to rotate. The state where the member is locked, the state where the lock is released by the input torque from the input side member under this state, and the input torque from the input side member is transmitted to the output side member under this unlocked state The state of being repeated causes a situation that it appears repeatedly.

As a result, the output side member may cause a so-called stick-slip phenomenon in which the output side member repeatedly locks and rotates, and it is feared that torque transmission is performed in a state where a jerky feeling or a chattering feeling occurs. In addition, there is a risk that smooth lowering of the lifted body may be hindered, and an abnormal noise may be generated or the operation feeling may be deteriorated in the case of manual operation.

The present invention has been made in view of the above circumstances, and when the input side member of the reverse input cutoff clutch having the above-described structure is rotated, the speed is higher in the same direction as the input side member. Even if the rotation can be imparted to the output side member, it is a technical object to prevent the occurrence of the stick-slip phenomenon in which the output side member repeatedly locks and rotates, and to smooth the rotation of the output side member. To do.

[0010]

In order to solve the above technical problems, the present invention is directed to an input side member to which a rotation torque is input, an output side member to which a rotation torque is output, and a stationary member in which rotation is restricted. A side member, locking means provided between the stationary side member and the output side member, for locking the output side member and the stationary side member against a reverse input torque from the output side member; Lock release means provided on the input side member for releasing the locked state of the lock means against the input torque from the input side member; and the lock release means provided between the input side member and the output side member. A reverse input cutoff clutch comprising: torque transmitting means for transmitting the input torque from the input side member to the output side member when the locked state by the means is released,
It is characterized in that a friction imparting means is provided for applying a frictional resistance to the output side member when the output side member is rotated with respect to the stationary side member.

According to this structure, when the rotational torque is input to the input side member in the stopped state, first,
The locked state by the lock means is released by the lock release means, and in that state, the rotational torque from the input side member is transmitted to the output side member via the torque transmitting means. On the other hand, the reverse input torque from the output side member is locked between the output side member and the stationary side member via the locking means. Therefore,
A function is provided in which the input torque from the input side is transmitted to the output side and the reverse input torque from the output side is not returned to the input side.

In this case, when the output side member is rotating with respect to the stationary side member, a frictional resistance acts on the output side member by the operation of the friction imparting means, so that a rotational torque is applied to the input side member. Even when the rotation speed of the output side member becomes higher than the rotation speed of the input side member during input, and the output side member can be locked due to reverse input from the output side member, A braking force due to frictional resistance acts on the member, and its rotation is suppressed. As a result, the output side member is prevented from being locked, so that it becomes difficult for the output side member to be repeatedly locked, unlocked, and transmitted with torque from the input side member. Generation is suppressed, and the rotation of the output side member is smoothed.

In the above structure, the friction applying means is
It is preferably arranged outside the clutch body, in other words, externally attached. With this configuration,
It is possible to make the clutch body of the reverse input cutoff clutch compact and to use the reverse input cutoff clutch for applications in which friction imparting means is unnecessary, for example, when the weight of the lifted body in the above-mentioned lifting device does not matter. The reverse input cut-off clutch used in the above and the clutch body can be shared, which is advantageous in terms of mass production and cost reduction.

In the above structure, the friction applying means is
It is preferable that the stationary side member and the output side member are arranged so as to straddle the stationary side member and the output side member. That is, this friction imparting means is
Although it is possible to dispose the fixing member other than the constituent elements of the reverse input cutoff clutch and the output side member, the stationary side member and the output side member, which are the constituent elements of the reverse input cutoff clutch, are thus arranged. By arranging them straddling, unitization and downsizing are promoted, and transportation, carrying and handling are convenient.

In the above structure, the friction applying means is
It is preferable that the output side member can rotate integrally with the output side member and can relatively rotate in frictional contact with the outer peripheral surface of the stationary side member. With this configuration, the frictional resistance generated by the frictional contact with the outer peripheral surface of the stationary side member acts on the output side member, so that the output side member is not worn due to friction and contributes to the torque output. It is possible to effectively suppress the early deterioration of the important member and the early inhibition of the clutch function.

In the above structure, the friction applying means is
It is preferable to provide a resin friction member that makes frictional contact with the outer peripheral surface of the stationary member. That is, it is possible to bring a metal member into frictional contact with the outer peripheral surface of the stationary member, but if this is done, abnormal noise (metal sound) is generated or wear occurs on the stationary member, Further, although there is a possibility that sufficient frictional resistance cannot be obtained, the probability of occurrence of such a problem becomes extremely low in the case of a resin friction member.

In the above structure, it is preferable that the resin friction member is held by a metal spring member integrally rotatably attached to the output side member so as not to rotate relative to each other. With this configuration, the desired frictional resistance can be obtained only by pressing the resin friction member against the outer peripheral surface of the stationary member by the spring force of the metal spring member. It is possible to simplify, reduce the number of parts, and further reduce the price.

The reverse input cutoff clutch having the above structure is preferably used for the lifting device. That is, in the lifting device including the reverse input cutoff clutch of this type, as described above, the rotational force is generated by the weight of the lifted body, and the rotation speed of the output side member is higher than that of the input side member. When it becomes large, the frequency of occurrence of stick-slip phenomenon is extremely high, but the effect of the above-mentioned friction imparting means can remarkably obtain the avoidance effect against such a defect.

Here, the above-mentioned "locking means" gives a rotation restraining force by a wedge engaging force, a concave and convex engaging force, a frictional force, a magnetic force, an electromagnetic force, a fluid pressure, a fluid viscous resistance force, a fine particle medium, or the like. However, in view of simplification of the structure and control mechanism, smooth operation, cost, etc., it is preferable to apply the rotation restraining force by the wedge engaging force. Specifically, a wedge gap is formed between the output side member and the stationary side member, and the engaging element is wedge-engaged / disengaged with respect to the wedge gap,
It is better to have a configuration that switches between locking and idling. Further, in this configuration, a cam surface for forming a wedge gap is provided on the output side member or the stationary side member (roller as an engaging element,
Use a circular cross section such as a ball. ), A structure in which a cam surface for forming a wedge gap is provided on the engaging element (a sprag or the like is used as the engaging element).

Further, the above-mentioned "locking means" forms a wedge gap between the circumferential surface provided on the stationary side member and the circumferential surface provided on the output side member in both forward and reverse rotation directions. A cam surface, a pair of engagement elements interposed between the cam surface and the circumferential surface,
An elastic member that presses each of the pair of engagement elements in the direction of the wedge gap may be provided. Further, the above-mentioned "lock releasing means" can be an engaging element that selectively engages with one of the pair of engaging elements and presses it in the direction opposite to the direction of the wedge gap. . Further, the above-mentioned "torque transmitting means" may be engaging elements in the rotational direction provided on the input side member and the output side member. Then, at the neutral position of the “lock releasing means” and the “torque transmitting means”, the rotational gap δ1 between the engaging element and the engaging element of the “lock releasing means” and the “torque transmitting means”.
The rotational gap δ2 between the engaging elements may have a relationship of δ1 <δ2.

With the above construction, when a reverse input torque in one direction is input to the output side member, one of the pair of engaging elements is wedge-engaged with the wedge gap in that direction to output the output. When the side member is locked in one direction with respect to the stationary member and the reverse input torque in the other direction is input to the output member, the other of the pair of engaging elements is wedge-engaged with the wedge gap in that direction. do it,
Lock the output member in the other direction with respect to the stationary member.
Therefore, the output side member is locked in both the forward and reverse rotation directions with respect to the stationary side member via the pair of engaging elements. On the other hand, when the input torque is input to the input side member, first, the engagement element serving as the lock release means provided in the input side member forms the wedge gap in the direction of the input torque among the pair of engagement elements. The wedge-engaging element is pressed in the direction opposite to the direction of the wedge gap to disengage it from the wedge gap. As a result, the locked state of the output side member is released in the direction of the input torque. Next, in the state where the output side member is unlocked, the engaging elements in the rotational direction as the torque transmitting means provided on the input side member and the output side member engage with each other. As a result, the input torque input to the input side member is transmitted through the route of the input side member → the torque transmitting means (engaging element in the rotation direction) → the output side member, and the output side member rotates.

Further, in the neutral position of the lock releasing means and the torque transmitting means, the rotational gap δ1 between the engaging element and the engaging element of the lock releasing means and the rotational gap δ2 between the engaging elements of the torque transmitting means. By setting the relations δ1 <δ2, it is possible to sequentially and reliably perform the unlocking by the unlocking means and the torque transmission by the torque transmitting means.

[0023]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

1 and 2 show the overall structure of a reverse input cutoff clutch according to an embodiment of the present invention. The clutch of this embodiment includes the input side member 1 to which torque is input.
An output side member 2 for outputting torque, a stationary side member 3 for which rotation is restricted, a fixed side plate 4 fixed to the stationary side member 3, a locking means, an unlocking means, and a torque transmitting means described later. It consists of and as the main elements.

The input-side member 1 has a ring-shaped plate-like substrate portion 1a having a boss portion 1x in which a shaft hole forming body 5 is fitted and fixed at a center portion in the radial direction, and an axial direction from the outer periphery of the substrate portion 1a. A plurality of (for example, six) column portions 1b continuously extending in one direction (inward direction of the clutch), and a plurality of protrusion portions formed in the axial direction from the middle of the boss portion 1x of the substrate portion 1a and the column portion 1b. It is mainly composed of (for example, 6 pairs) protrusions 1c. The protrusion 1c has a cylindrical shape in this embodiment. In addition, the shaft hole forming body 5
The shaft hole 5a has two flat surfaces 5b, and the flat surfaces of the flat surface formed on the connecting portion of the input shaft and the flat surfaces 5b of the shaft hole 5a are fitted to each other by the flat fitting, whereby the input shaft and the input side are The member 1 is connected so as not to rotate relative to it.

The pillar portion 1b and the protruding portion 1c are arranged at equal intervals around the circumference, and the positions of the pillar portion 1b and the protruding portion 1c are displaced from each other in the circumferential direction. The protrusion 1c is located at an intermediate position between the pillars 1b adjacent to each other in the circumferential direction. A pocket 7 that is a space that is open toward one side in the axial direction is formed between the pillar portions 1b that are adjacent to each other in the circumferential direction, and a pair of rollers 6 is arranged in each pocket 7 (for details, see See below).

The output side member 2 has a flange portion 2a extending in a radial direction, an output shaft portion 2b continuously extending in one axial direction from an inner circumference of the flange portion 2a, and an outer circumference of the flange portion 2a. And a large-diameter portion 2c that continuously extends from the other to the other in the axial direction, and a plurality of (for example, six) recesses 2d are formed on the other side surface portion in the axial direction of the large-diameter portion 2c. .
Then, the plurality of projections 1c of the input side member 1 are loosely fitted in the plurality of recesses 2d with predetermined rotational gaps.

At the shaft end portion of the output shaft portion 2b, for example, 1
One flat surface portion 2e is provided {see FIG. 1 (b)}, and this shaft end portion is connected to a rotating member of an output side mechanism or device (not shown), and The output shaft portion 2b and the rotating member are connected to each other so as not to rotate relative to each other by the plane fitting with the flat surface portion formed on the rotating member. Further, the flat surface portion 2e of the shaft end portion of the output shaft portion 2b is also used for mounting the friction imparting means 10 described later.

The large-diameter portion 2c of the output side member 2 has a polygonal shape (for example, a regular hexagonal shape) in the example shown in FIG. 2, and the outer periphery of each side is a cam surface 2f, and the 6
Two cam surfaces 2f are arranged on the outer circumference of the large diameter portion 2c at equal intervals in the circumferential direction.

The stationary side member 3 has an annular plate-shaped side plate portion 3b having a cylindrical portion 3a continuously extending in one axial direction at the center in the radial direction, and an axial direction from the outer periphery of the side plate portion 3b. The main part is composed of a large-diameter covering portion 3c extending to the other side, and a flange portion 3e projecting outward from one end of the large-diameter covering portion 3c.

Between the inner peripheral surface of the tubular portion 3a of the stationary member 3 and the outer peripheral surface of the axially intermediate portion (non-formation portion of the flat portion 2e) of the output shaft portion 2b of the output member 2. A radial bearing member 8 is provided.

Further, on the inner circumference of the large diameter covering portion 3c of the stationary side member 3, a circle is formed which faces the cam surface 2f of the output side member 2 in the radial direction and forms a wedge gap in both the forward and reverse rotation directions. A peripheral surface 3f is provided.

A plurality of (eg, six) rectangular notches 3g are formed at equal intervals in the circumferential direction on the flange 3e of the stationary member 3 and these notches 3g (one The total of the three notches 3g) fits with the caulking portion 4c of the fixed side plate 4 described later. The other cutouts 3g are provided to avoid interference with the mounting bolts mounted on the fixed side plate 4.

The fixed side plate 4 includes a plurality of (for example, three) bracket portions 4b protruding from the outer periphery of the base side plate portion 4a toward the outer diameter side, and a non-protruding portion of the base side plate portion 4a in one axial direction. The main components are a plurality of (for example, three) caulking portions 4c protruding toward each other and an insertion hole 4d formed in the central portion of the base side plate portion 4a. Then, the input shaft connected to the input side member 1 is inserted into the insertion hole 4d. Further, each bracket portion 4b is formed with a through hole 4e, and a mounting bolt is inserted into each of these through holes 4e.

Each crimping portion 4c is provided with a pair of claws 4f which are formed at equal intervals in the circumferential direction and are bifurcated (see FIG. 2). Then, the caulking portion 4c is fitted into the cutout portion 3g of the stationary side member 3, the pair of claws 4f are folded back in opposite directions in the circumferential direction, and caulked to the collar portion 3e of the stationary side member 3, The stationary side member 3 and the fixed side plate 4 are coupled to each other in an axially and rotationally immovable manner.

As shown in FIG. 2, between the cam surface 2f of the output side member 2 and the circumferential surface 3f of the stationary side member 3, respectively,
A pair (for example, a total of 6 pairs) of rollers 6 serving as engaging elements are arranged and housed in a pocket 7 formed between the pillar portions 1b of the input side member 1. Further, an elastic member (spring) 9 that separates the rollers 6 from each other is interposed between the pair of rollers 6. The elastic member 9 is, for example, a thin spring plate portion bent and formed into a U-shaped cross section or a U-shaped cross section, and one piece portion 9a facing each other abuts on one roller 6 and the other one. 9a is in contact with the other roller 6.

In this case, the cam surface 2f, the circumferential surface 3f, the pair of rollers 6, and the elastic member 9 constitute a locking means, and the pair of rollers 6 are located on both sides in the circumferential direction of the input side. The column portion 1b (engagement element) of the member 1 constitutes lock releasing means, and the projection 1c of the input side member 1 and the recess 2d of the output side member 2 into which the projection 1c is loosely fitted.
A torque transmitting means is constituted by and. Note that, for example, grease is filled in the space between the outer circumference of the output side member 2 and the inner circumference of the stationary side member 3, especially between the cam surface 2f and the circumferential surface 3f.

In addition to the above construction, this reverse input cutoff clutch is rotatable integrally with the output side member 2 and is in frictional contact with the outer peripheral surface of the large diameter covering portion 3c of the stationary side member 3. Relatively rotatable friction imparting means 10 is provided. The friction imparting means 10 is provided outside the clutch body composed of the above-described constituent elements 1 to 9, and is provided with a metal spring member 10a made of spring steel or the like and a resin friction member made of Duracon or the like. It is composed of a member 10b.

As shown in FIG. 3, the metal spring member 10a has an annular plate-like annular shape with a fitting hole 10c fitted in the output shaft portion 2b of the output side member 2 at the center in the radial direction. Base 10d,
A plurality of (for example, six) claw-shaped portions 10e extending in a crown shape from the outer circumference of the annular base portion 10d toward the other in the axial direction are integrally formed. The fitting hole 10c has a flat surface portion 10f corresponding to the flat surface portion 2b of the shaft end portion of the output shaft portion 2b. By flatly fitting both flat surface portions 2f, 10f, the metal spring member 10a. Are integrally and rotatably coupled to the output side member 2. Further, the claw-shaped portions 10e are formed at equal intervals in the circumferential direction, and the tips of the claw-shaped portions 10e are slightly bent toward the outer diameter side, and the bent portions 10g are made of resin. It serves as a pressing portion for the friction member 10b.

As shown in FIG. 4, the resin-made friction member 10b has a ring-shaped plate portion 10h and a plurality (for example, six) extending from the outer periphery of the ring portion 10h toward the other side in the axial direction.
The projecting piece portion 10i is integrally formed. The projecting piece portions 10i are formed at equal intervals in the circumferential direction, and the inner peripheral surface of each projecting piece portion 10i is an arc surface that makes frictional contact with the outer peripheral surface of the stationary side member 3, and Engagement recesses 10j with which the tips of the claw-shaped portions 10e of the metal spring members 10a are engaged are formed on the outer peripheral surface of each projecting piece 10i.
In addition, at the tip of each protrusion 10i of the resin friction member 10b,
A bent portion 10k that is slightly bent toward the outer diameter side is formed, and this bent portion 10k performs axial positioning of each claw-shaped portion 10e of the metal spring member 10a.

The annular plate-shaped ring portion 10h of the resin friction member 10b does not have to be continuous in the circumferential direction as described above. For example, as shown in FIG. The ring portions 10h may be formed intermittently at intervals.

As shown in FIG. 1 (a), the friction imparting means 10 having the above-mentioned structure is such that the metal spring member 10a is brought into contact with the stepped surface of the output shaft portion 2b of the output side member 2 and Output side member 2
The resin friction member 10
The inner peripheral surface of each protruding piece 10i of b is brought into contact with the outer peripheral surface of the stationary side member 3 and the ring portion 10h is brought into contact with the outer surface of the side plate portion 3b of the stationary side member 3 so that the outer periphery of each protruding piece 10i is engaged. By engaging the tips of the claw-shaped portions 10e of the metal spring member 10a with the fitting recesses 10j, they are externally attached to the clutch body. Under this condition,
By the spring force of each claw-shaped portion 10e of the metal spring member 10a, each protruding piece 10i of the resin friction member 10b is pressed against the outer peripheral surface of the stationary side member 3,

Next, the main operation of the reverse input cutoff clutch having the above structure will be described with reference to FIGS.

As shown in the enlarged view of FIG. 6, in the neutral position, the pair of rollers 6 are pressed by the elastic member 9 in the directions away from each other, and the cam surface 2f and the circumferential surface 3f are respectively pressed.
Engages with the wedge gaps formed in the forward and reverse directions. At this time, there is a rotational gap δ1 between each column portion 1b of the input side member 1 and each roller 6. Further, between the concave portion 2d of the output side member 2 and the projection portion 1c of the input side member 1, there are rotational gaps δ2 in both the forward and reverse rotational directions. The rotational gap δ1 and the rotational gap δ2 are δ1 <
It has a relationship of δ2. The size of the rotational gap δ1 is, for example, 0 to 0.4 mm (0 to about the clutch axis).
The size of the rotational gap δ2 is, for example, 0.4 to 0.8 mm (1.
It is about 8 to 3.7 °).

In the state shown in FIG. 6, for example, the output side member 2
When a counterclockwise reverse input torque is input to, the counterclockwise (rotational rear) roller 6 wedge-engages with the wedge gap in that direction, and the output side member 2 moves in a clockwise direction with respect to the stationary side member 3. Locked in the direction. When a counterclockwise reverse input torque is input to the output side member 2, the roller 6 in the clockwise direction (rearward in the rotational direction) engages with the wedge gap in that direction, and the output side member 2 causes the stationary side member 3 to move. Is locked counterclockwise. Therefore, the reverse input torque from the output side member 2 is locked by the roller 6 in both forward and reverse rotation directions.

FIG. 7 shows an initial state in which an input torque (clockwise in the figure) is input to the input side member 1 and the input side member 1 starts to rotate clockwise in the figure. Since the gap in the rotation direction is set to δ1 <δ2, first, the counterclockwise (rearward in the rotation direction) column portion 1b of the input member 1 engages with the roller 6 in that direction (rearward in the rotation direction). This is pressed in the clockwise direction (forward in the rotational direction) against the elastic force of the elastic member 9. As a result, the roller 6 in the counterclockwise direction (rearward in the rotational direction) is released from the wedge gap in that direction, and the locked state of the output side member 2 is released {the roller 6 in the clockwise direction (forward in the rotational direction) is released. , Does not engage with the wedge gap in that direction. }. Therefore, the output side member 2 can be rotated clockwise.

When the input side member 1 further rotates in the clockwise direction, as shown in FIG. 8, the projection 1c of the input side member 1 engages with the recess 2d of the output side member 2 in the clockwise direction. This allows
The clockwise input torque from the input side member 1 is transmitted to the output side member 2 via the engaging portion between the protrusion 1c and the recess 2d,
The output side member 2 rotates clockwise. When a counterclockwise input torque is input to the input side member 1, the output side member 2 rotates counterclockwise by the operation opposite to the above. Therefore, the input torque from the input side member 1 in both the normal and reverse rotation directions is transmitted to the output side member 2 via the projection 1c and the recess 2d as the torque transmission means, and the output side member 2 is rotated in the forward and reverse rotation directions. Turn to. When the input torque from the input side member 1 disappears, the elastic restoring force of the elastic member 9 restores the neutral position shown in FIG.

In this case, when the above-mentioned reverse input cutoff clutch is used in the lifting device for vertically moving the lifted body, the rotational torque generated by the drive motor or manually is input to the input side member 1 as the input torque. On the other hand, the rotation torque generated by the weight of the lifted body is input to the output side member 2 as the reverse input torque. Then, when the force for rotating the input side member is larger than the force for rotating the output side member in the same direction, even if the output side member 2 is in a freely rotatable state, The reverse input cutoff clutch operates as described above.

On the other hand, in the state shown in FIG. 8, the rotation speed r2 of the output side member 2 can be higher than the rotation speed r1 of the input side member 1 due to the weight of the lifted body. In such a case, if the output side member 2 is in a freely rotatable state, a reverse input from the output side member 2 shifts from the state shown in FIG. 7 to the state shown in FIG. The output side member 2 will be locked. Immediately after this, the state shown in FIG. 6 again shifts to the state shown in FIG. 7, torque is transmitted to the output side member 2, and the output side member 2 starts to rotate again, that is, a stick-slip phenomenon. Occurs.

However, in this reverse input cutoff clutch, the friction applying means which can rotate integrally with the output member 2 is provided.
Since the metal spring member 10a of 10 and the resin friction member 10b rotatable integrally with the metal spring member 10a are in frictional contact with the stationary member 3, frictional resistance is imparted to the output member 2 during its rotation. That is, in the state shown in FIG. 8, the output side member 2
The frictional resistance necessary to prevent the rotational speed r2 of the input side member 1 from exceeding the rotational speed r1 of the input side member 1 is imparted. Therefore, the situation in which the output side member 2 is locked by the reverse input from the output side member 2 does not occur, and for example, when the lifted body is lowered in the lifting device, the reverse input cutoff clutch continues the state shown in FIG. This can be maintained, and the rotation of the output side member 2 can be smoothed.

[0051]

As described above, according to the reverse input cut-off clutch according to the present invention, the friction applying means for applying frictional resistance to the output side member when the output side member is rotated with respect to the stationary side member is provided. Even if the rotational speed of the member can be higher than the rotational speed of the input side member, the braking force due to the frictional resistance acts on the output side member and the rotation thereof is suppressed. Therefore, the problem that the output member is locked is avoided, and the stick-slip phenomenon in which locking and rotation are repeatedly applied to the output member is less likely to occur, and as a result, the rotation of the output member is smooth. Be converted.

By disposing the friction applying means outside the clutch main body, the clutch main body of the reverse input breaking clutch can be made compact, and the reverse input breaking clutch used for applications where the friction applying means is unnecessary. And the clutch body can be shared, which is advantageous for mass production and cost reduction.

Further, by disposing the friction applying means over the stationary side member and the output side member, unitization and downsizing can be further promoted, and transportation, carrying and handling are convenient. Planned.

Further, by making the friction applying means rotatable integrally with the output side member and capable of rotating relative to the outer peripheral surface of the stationary side member by relative rotation, the output side member is not worn due to friction. It is possible to effectively suppress the early deterioration of important members related to the torque output and the early inhibition of the clutch function.

Further, since the friction applying means is provided with the resin friction member which makes frictional contact with the outer peripheral surface of the stationary member, abnormal noise (metal sound) is generated, the stationary member is worn, and further friction is caused. Problems such as insufficient resistance can be effectively avoided.

Further, by holding the resin friction member on the metal spring member integrally rotatably attached to the output side member such that the resin friction member cannot rotate relative to the output side member, only the spring force of the metal spring member allows the resin friction member to be rotated. Since it is possible to obtain the desired frictional resistance by pressing against the outer peripheral surface of the stationary member, it is possible to simplify the structure of the friction applying means, reduce the number of parts, and further reduce the cost.

By using this reverse input cut-off clutch in the lifting device, the rotation speed of the output side member becomes higher than the rotation speed of the input side member due to the weight of the lifted body, and the stick-slip phenomenon occurs. It is possible to appropriately avoid the problem that occurs.

Claims (7)

[Claims] 1. An input side member to which rotational torque is input,
An output-side member that outputs a rotational torque, a stationary-side member that is restricted from rotating, and a stationary-side member that is provided between the stationary-side member and the output-side member, and that is configured to handle the reverse input torque from the output-side member Lock means for locking the output side member and the stationary side member; lock release means provided in the input side member for releasing the locked state by the lock means with respect to the input torque from the input side member; Torque transmitting means provided between the input-side member and the output-side member and transmitting the input torque from the input-side member to the output-side member when the locked state by the locking means is released. A reverse input disconnecting clutch including: a reverse input clutch, comprising: a friction applying unit that exerts a frictional resistance on the output member when the output member rotates with respect to the stationary member. Power cut clutch. 2. The reverse input cutoff clutch according to claim 1, wherein the friction applying means is arranged outside the clutch body. 3. The reverse input cutoff clutch according to claim 1, wherein the friction applying means is disposed so as to straddle the stationary side member and the output side member. 4. The friction applying means is integrally rotatable with the output side member, and is relatively rotatable in frictional contact with the outer peripheral surface of the stationary side member. Reverse input cutoff clutch as described. 5. The reverse input cutoff clutch according to claim 4, wherein the friction applying means includes a resin friction member that makes frictional contact with the outer peripheral surface of the stationary side member. 6. The reverse input cutoff clutch according to claim 5, wherein the resin friction member is held so as to be relatively non-rotatable by a metal spring member integrally rotatably attached to the output side member. 7. The reverse input cutoff clutch according to claim 1, which is used in a lifting device.