JPH0829443B2 - Tool chuck - Google Patents

Description

TECHNICAL FIELD The present invention relates to a tool chuck that is mounted on, for example, an electric drill or an electric screwdriver, and that can perform a tightening operation of a tool without using a chuck handle.

(B) Conventional Technology Conventionally, as the tool chuck described above, for example, a nut ring loosely fitted in the chuck body is normally and reversely rotated by rotating an operation ring, and a plurality of nuts screwed to the nut ring are screwed. There is a tool chuck (Japanese Utility Model Laid-Open No. Sho 63-189509) in which each chuck claw is expanded and contracted in the tool clamping direction to clamp and fix the tool.

(C) Problems to be Solved by the Invention However, in the above-mentioned tool chuck, since the turning force of the operation ring by manual operation is converted into the direction in which the plurality of chuck claws are expanded and contracted via the screw feed mechanism, It is structurally difficult to obtain a tightening force equivalent to that when using a handle, and it is structurally difficult to obtain a tightening force higher than the torque amplified by the screw feed mechanism. It has a problem that it is apt to rattle and loosen and is not applicable to use conditions requiring high torque.

In view of the above problems, an object of the present invention is to provide a tool chuck in which the tool can be firmly tightened and fixed only by manually rotating the operation ring, and the tightening and fixing operations can be easily performed.

(D) Means for Solving the Problem The present invention provides a torque-up mechanism between the transmission paths of the operation ring and the nut ring, and the torque-up mechanism is arranged so that the input / output ring is biased with respect to the operation ring. The chuck body is loosely fitted to the chuck body, and the fixing ring is loosely fitted coaxially to the chuck body, and gears having a difference in the number of teeth are engraved and meshed on the facing surfaces of the input / output ring and the fixing ring. And a fixing ring, a pressure chucking portion that is pressed against and fixed by a reaction force due to the tightening of the nut ring is provided on the opposing surface, and the input / output ring and the nut ring are connected so that power can be transmitted. Characterize.

(E) Operation According to the tool chuck of the present invention, by rotating the operation ring in the direction in which the tool is clamped, a load due to the clamping of the tool is applied to the chuck claws at the initial stage of rotation. Since the fixing ring that constitutes the torque-up mechanism is rotatable with respect to the chuck body, the operation ring, the input / output ring, and the fixing ring rotate integrally, and the nut ring By screw feeding, multiple chuck claws can be swiftly and slid to clamp the tool.

Furthermore, when the operation ring is rotated in the tightening direction and the tool is clamped by the chuck claws, a load is generated on the chuck claws and the nut ring retracts due to the reaction force due to the tightening, which causes the pressure contact part between the fixing ring and the chuck body. Pressed to rotate and fixed, the deceleration action is generated by the torque up mechanism.

That is, when the operation ring is rotated, the input / output ring is rotated or revolved around the center point of the fixed ring due to its eccentricity, that is, the input / output ring is revolved around the fixed ring gear. Rotate while moving the mesh point.

In this movement of the gear meshing point, a difference in the number of teeth is set between the two gears, and therefore a difference in movement (a difference in rotation) in the input / output ring, that is, a rotation other than the revolution occurs in the input / output ring.

Moreover, since the rotation of the input / output ring has a difference in the number of teeth with respect to one revolution, the revolution input is decelerated, and the deceleration output has a high torque.

Then, the nut ring is rotated by the output of the high torque input / output ring, and the plurality of chuck claws are screw-fed to clamp and fix the tool with high torque.

The above reduction ratio is, for example, when the number of gear teeth of the input / output ring is 68, the number of gear teeth of the fixed ring is 66, and the difference in the number of teeth is 2 (68-66) / 66 sheets = 2 sheets / 66 sheets = 1/33, and high torque can be obtained with large deceleration.

(F) Effect of the Invention As a result of the above, according to the present invention, since the turning force of the operating ring is greatly reduced by the torque-up mechanism when the tool is clamped, the operating ring is rotated by the nut ring screwed to the chuck claw. A torque higher than that of directly transmitting power is obtained, and by simply rotating the operating ring in the tightening direction, the tool can be firmly tightened and fixed with a high torque according to the operating conditions, and a large torque The mechanism for obtaining can be easily configured by gears.

Moreover, the operation ring, the input / output ring, and the fixing ring rotate integrally under a transmission load during the rotation operation until the tool is tightened and fixed and during the rotation operation after the tightening is released, As a result, the rotation of the operation ring becomes the rotation of the nut ring, and the plurality of chuck claws can be rapidly expanded and contracted by the rotation operation of the operation ring to tighten or fix the tool. Excellent operability.

(G) Embodiment of the Invention One embodiment of the present invention will be described in detail below with reference to the drawings.

The drawing shows a tool chuck in which a tool such as a drill bit or a driver bit is clamped by an electric drill or an electric screwdriver. In FIG. 1, the tool chuck 1 is an outer periphery of an intermediate portion of a chuck body 2 formed in a cylindrical shape. On the surface, three guide holes 3 ... Are formed in an oblique direction gathering toward the center part on the tip side, and three chuck claws 4 ... are inserted into these guide holes 3 ... There is.

An annular notch 5 is formed by cutting out a part of each of the three guide holes 3 on the outer peripheral surface of the intermediate portion of the chuck body 2 described above, and the annular notch 5 can be divided into two parts. 6 is loosely fitted and the female screw 6a screwed on the inner peripheral surface of the nut ring 6 and the male screw 4a screwed on the outer peripheral surface of the base end portion of each chuck claw 4 are screwed together. A sleeve 7 is press-fitted and integrally fixed to the outer peripheral surface of the split rings 6b, 6b constituting the nut ring 6 on the tip side.

That is, by rotating the nut ring 6 in the normal and reverse directions, the three chuck claws 4 ... Are screw-fed in the expansion / contraction direction along the guide holes 3 ..., and the tool A is moved by the chuck claws 4 ... Hold and release the clamp.

The operation ring 8 formed in a cylindrical shape is rotatably loosely fitted to the outer peripheral surface of the intermediate portion of the chuck body 2 described above, while the cylindrical outer shape is formed on the outer peripheral surface of the proximal end portion of the chuck body 2. The ring 9 is integrally fitted and fixed.

Between the power transmission path between the nut ring 6 and the operation ring 8, the turning force of the operation ring 8 is applied to the nut ring 6.
A torque-up mechanism 10 is provided for transmitting power to the.

The torque increasing mechanism 10 is composed of an input / output ring 11 loosely fitted to the inner peripheral surface of the operation ring 8 and a fixed ring 12 loosely fitted to the outer peripheral surface of the chuck body 2.

The outer peripheral surface of the input / output ring 11 on the distal end side is loosely fitted on the outer peripheral surface of the tubular operating portion 14 formed on the inner peripheral surface of the central portion of the operating ring 8 via the needle bearing 13.

As shown in FIG. 2, the outer peripheral surface of the cylindrical operation portion 14 is formed with an axis center C, which is eccentric with respect to the axis center B of the chuck body 2, as the center.

The inner peripheral surface of the central portion of the input / output ring 11 is meshed with the outer peripheral surface of the rear end portion of the nut ring 6 via the gear coupling 15 so that power can be transmitted.

That is, this gear coupling 15 is an input / output ring.
A gear 16 engraved on the inner peripheral surface of the central portion of 11 and a gear 17 engraved on the outer peripheral surface of the rear end portion of the nut ring 6 facing this e
It is meshed in a loose fitting state that allows eccentricity of dimensions.

Gears engraved on the inner peripheral surface of the rear end of the input / output ring 11 described above.
As shown in FIG. 3, the gear 18 is engaged with a gear 19 which faces the gear 18 and is formed on the outer peripheral surface of the fixed ring 12.

That is, these gears 18 and 19 constitute a cycloid gear that performs a cycloidal movement, and when the operation ring 8 is rotated and the input / output ring 11 is revolved by the eccentricity of the tubular operation portion 14, the input / output ring 11 is rotated. Due to the difference in the number of teeth between the gear 18 engraved on the fixed ring 12 and the gear 19 engraved on the fixed ring 12, the input / output ring 11 rotates due to the large number of teeth, and the operation ring 8
Since the rotation of the input / output ring 11 is greatly decelerated, the rotation output of the input / output ring 11 is increased in torque.

In the case of this embodiment, the number of teeth on the input / output ring 11 side is set to 68, and the number of teeth on the fixed ring 12 side is set to 66.

 As a result, the reduction ratio becomes (68-66) / 66 = 2/66 = 1/3, which is 1/33 for the input.

An appropriate number of thrust balls 20 are rotatably held between the facing surfaces of the nut ring 6 and the fixed ring 12 described above.

On the inner peripheral surface of the above-mentioned fixing ring 12, a tapered surface 21 having a diameter gradually increasing toward the rear end side is formed, and on the outer peripheral surface of the intermediate portion of the chuck body 2 facing this, the rear end side is formed. A tapered surface 22 having a gradually increasing diameter is formed.

When the tool A is clamped, the tapered surfaces 21 and 22 are pressed against each other by retracting the nut ring 6 due to the reaction force due to the tightening, so that the fixing ring 12 and the chuck body 2 are integrally pivoted and fixed.

A fixing ring is provided on the inner peripheral surface of the operation ring 8 on the rear end side.
The spring ring 23 is inserted and fitted so as to face the rear surface side of the spring 12, and the elastic piece 24 formed on the inner peripheral edge of the spring ring 23 is fixed to the fixing ring.
The notch surface 25 formed on the rear surface side of 12 provides an appropriate notch feel when the operation ring 8 is rotated, and the taper surfaces 21, 2 of the fixing ring 12 and the chuck body 2 are provided.
It is urged in the direction to release the pressure contact of 2.

A retaining ring 26 is press-fitted and fixed to the rear side of the above-mentioned spring ring 23, and the retaining ring 26 prevents the spring ring 23 from retaining and rotating.

Assuming that the illustrated embodiment is configured as described above,
The tightening operation and the releasing operation of the tool chuck will be described.

First, when the tool A is clamped by each of the three chuck claws 4, ... With the holding ring 9 being rotationally fixed, the operation ring 8 is clamped in the clamping direction D (solid line direction) for clamping the tool A.
Since the load due to the clamping of the tool A is not applied to the chuck claws 4 in the initial stage of rotation by rotating the, the fixing ring 12 that constitutes the torque-up mechanism 10 is not attached to the chuck body 2. Since it is in a rotatable state, the operation ring 8, the input / output ring 11, and the fixed ring 12 are integrally rotated by a transmission load, and the screw feeding of the nut ring 6 causes the three chuck claws 4 to move. ... is swiftly slid to clamp Tool A.

Next, when each of the three chuck claws 4 comes into contact with the tool A and a clamping load is applied, the nut ring 6 is retracted by the reaction force due to the tightening, and the fixing ring is inserted via the thrust ball 20.
12 is retracted to the rear end side, whereby the fixing ring 12 and the taper surfaces 21 and 22 of the chuck body 2 are pressure-contacted, and the fixing ring 12 and the chuck body 2 are integrally fixed, and the torque increasing mechanism 10 Generate a deceleration action.

FIG. 4 shows the deceleration principle of the torque-up mechanism 10 described above. In FIG. 4A, the number of teeth of the gear 18 of the input / output ring 11 is 68, and the apex position is the 0th (68). 17th sheet at the 90 ° position in the tightening direction D, the 34th sheet at the 180 ° position, the 51st sheet at the 270 ° position, and the 360 ° position.
68th sheet.

Further, the number of teeth of the gear 19 of the fixed ring 12 is 66,
When the position of the apex is the 0th sheet (66th sheet), the 16.5th sheet at the 90 ° position in the tightening direction D, the 33rd sheet at the 180 ° position, the 50.5th sheet at the 270 ° position, and the 360 ° 66th sheet at the position.

When the input / output ring 11 is rotated based on the rotation of the operation ring 8 in the tightening direction D, this rotation causes the center point C of the input / output ring 11 with respect to the center point B of the fixed ring 12. Since it is eccentric by the dimension e, the center point C of the input / output ring 11 rotates about the center point B of the fixed ring 12, and this rotation causes the input / output ring with respect to the fixed ring 12.
11 revolutions.

When the revolving of the input / output ring 11 is performed 90 degrees as shown in FIGS. 4A to 4B, the meshing points of the gear 18 and the gear 19 are sequentially moved, and the mutual gears are rotated. Although the number of meshing teeth of 18, 19 is 16.5, the original 90 of the input / output ring 11
The 17th position of the degree position is positioned 0.5 points ahead of the 90 degree position of the fixing ring 12.

Further, when the revolution of the input / output ring 11 reaches 180 degrees as shown in FIG.
The position of the 34th sheet is located one position ahead of the 180 degree position of the fixed ring 12.

Furthermore, Fig. 4D shows the revolution of 270 degrees, and Fig. 4E shows 3
When the revolution of the input / output ring 11 reaches 360 degrees, the 66th sheet (0th sheet) at the apex of the fixed ring 12 and the 66th sheet of the apex of the output ring 11 are located. However, the 68th (0th) position of the input / output ring 11, which is originally at the 360-degree position, is two positions ahead of the 360-degree position (vertex) of the fixed ring 12. To be done.

As a result, one revolution of the input / output ring 11 causes the input / output ring 11 to rotate by two teeth, and this rotation is the rotation of the input / output ring 11.

The rotation of this input / output ring 11 is (68-66) / 66 = 2/66 = 1/3 in terms of the number of teeth, and the input / output ring 11 is rotated by operating the operation ring 8. To
When the orbit is applied 33 times, the input / output ring 11 is rotated once, and the reduction ratio with respect to the input from the operation ring 8 is extremely large at 1/33 as described above. High torque can be obtained.

When the operation ring 8 is rotated based on such a deceleration principle, the torque-up mechanism 10 outputs a high torque to the input / output ring 11, and the output of the high-torque input / output ring 11 causes the gear coupling 15 to move. The nut ring 6 is rotated to feed the plurality of chuck claws 4 by screws to clamp and fix the tool A with high torque.

When removing the tool A, the operation ring 8 may be rotated in the loosening direction E (dotted line direction).

In this case, when the three chuck claws 4 ... Retreat and the reaction force due to tightening does not act on the nut ring 6, the fixing ring 12 is moved forward by the urging force of the spring ring 23, and Tapered surface 21,22 with chuck body 2
The pressure contact fixing by is released, the deceleration action is released by the torque up mechanism 10, and the operation ring 8 and the input / output ring 1 are released.
1, the fixing ring 12 is rotated integrally, the nut ring 6 is rotated at the same speed as the rotation of the operation ring 8, and the three chuck claws 4 ... The chuck claws 4 ... Are rapidly expanded and slid to release the holding and fixing of the tool A.

In this way, when the tool A is clamped, the turning force of the operation ring 8 is reduced by the torque increasing mechanism 10.
A torque higher than that when the turning force of the operation ring 8 is directly transmitted to the nut ring 6 screwed to each chuck claw 4 of the book is obtained, and the tool A is operated by simply rotating the operation ring 8 in the tightening direction. Can be firmly tightened and fixed.

Moreover, the operation ring 8, the input / output ring 11, and the fixing ring 12 are integrally reversed in the middle of the rotating operation until the tool A is clamped and fixed and during the rotating operation after the tightening is released. It is possible to rotate, and the screw feeding of the nut ring 6 allows the three chuck claws 4 to be rapidly expanded / contracted, whereby the tool A can be clamped / fixed or unfixed, which is excellent in operability.

In the correspondence between the configuration of the present invention and the above-described embodiment, the press contact portion of the present invention corresponds to the tapered surfaces 21 and 22 of the embodiment, but the present invention is limited to the configuration of the above-described embodiment. It is not something that will be done.

For example, the inner peripheral surface of the operation ring 8 is formed eccentrically with respect to the axial center B of the chuck body 2 by the dimension e, and the input / output ring 11 loosely fitted to the inner peripheral surface of the operation ring 8 is revolved. Good.

[Brief description of drawings]

The drawings show one embodiment of the present invention, FIG. 1 is a vertical sectional side view of a tool chuck, FIG. 2 is an operation explanatory view of a sectional view taken along the line II-II shown in FIG. 1, and FIG. 3 is FIG. And FIG. 4A to FIG. 4E are explanatory diagrams of the deceleration principle. A …… Tool, B, C …… Axis center, 1 …… Tool chuck, 2 …… Chuck body 4 …… Chuck claw, 6 …… Nut ring 8 …… Operating ring, 10 …… Torque up mechanism 11 …… Input / output ring, 12 …… Fixing ring 14 …… Cylindrical operation part, 18,19 …… Gear 21,22 …… Tapered surface

Claims (1)

[Claims] Claims: 1. A plurality of chuck claws are held in a central portion on the tip side of a chuck body so that they can be expanded and contracted, and a nut ring screwed to each of these chuck claws is rotatably operated by an operation ring to make each chuck. A tool chuck for expanding and contracting a claw, wherein a torque-up mechanism is provided between the transmission paths of the operation ring and the nut ring, and the torque-up mechanism is provided with an input / output ring eccentric to the operation ring. And the fixing ring is loosely fitted coaxially to the chuck body, and gears having a difference in the number of teeth are engraved and meshed on the facing surfaces of the input / output ring and the fixing ring to fix the chuck body to the chuck body. A tool chuck formed by providing a pressure contact portion, which is fixed in pressure contact by a reaction force due to the tightening of the nut ring, on the surface facing the ring, and connecting the input / output ring and the nut ring so that power can be transmitted. Click.