JP2005096746A - Operation seat supporting device of working vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an operation seat supporting device of a working vehicle capable of miniaturizing a suspension mechanism, enhancing the function thereof, and realizing a comfortable operating posture. <P>SOLUTION: An operation seat 6 is mounted on a supporting plate 3 supported by at least two damper cylinders 50 and 30 at an installation place of a driver's seat via a posture adjustment mechanism 40, and at least one of the damper cylinders 50 and 30 is used as a damper cylinder (50) to perform the vibration damping function by using an MR fluid. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a driving seat support device for a work vehicle, which is mainly installed in a driver's cab of a construction machine vehicle, has a variable damping function, and can improve the feeling of use.

  Conventionally, driving seat support devices installed in the cab of construction machines such as hydraulic excavators and bulldozers have a greater impact transmitted to the seat on which the operator is seated than the driver's seat in a general industrial vehicle. Various measures are taken for the suspension structure.

As a suspension structure of a driving seat in this type of work vehicle, for example, one shown in FIGS. 9A and 9B is known. In this suspension structure, X-type links 102 that are crossed in the front-rear direction on the base member 101 and are coupled to the pins 103 at the crossing positions are arranged on the left and right sides at predetermined intervals. A link 110 whose height can be adjusted is provided between 102 and 102.
The X-type link 102 has the base end of one link 102a pivoted to the base member 101 side, the other end is connected to the seat mounting base frame 104 side by a pin 105, and the lower end side of the other link 102b is the base. The structure is such that the upper end of the member 101 is movable on the member 101 and is connected to the seat mounting base frame 104 by a pin 106 and cushioning is maintained by a suspension cylinder 107.
The height-adjustable link 110 is adapted to roll by engaging a roller 111 provided at the lower end thereof with a guide rail 108 attached to the base member 101 side, and the upper end of the link 110 is adjusted to the seat mounting base frame 104 side. Thus, it is connected to one end of the coil spring 112 so that tension is applied in the standing direction, and the weight and height can be adjusted by adjusting the tension of the spring 112 and displacing the link 110 in the vertical direction. A possible adjustment knob 113 is provided. In the figure, reference numeral 115 denotes a seat, and 116 denotes a suspension cover.

  Further, Patent Document 1 discloses a configuration in which a front portion is supported by a rubber spring system having a small elastic deformation in the vertical direction and a rear portion of the seat is supported by a coil damper unit system having a large elastic deformation in the vertical direction. A suspension mechanism for a driver's seat using the X-type link is also known, for example, from Patent Document 2.

JP-A-9-209406 JP-A-11-280117

However, in the driver seat support means employing the X-type link 102 as found in the prior art, the link 102 occupies the space under the seat 115 and compresses the feet.
In addition, since the damping damper is placed outside, there is a problem that the space cannot be used.
Furthermore, since the X link has a flat steel structure, there is a problem that the rigidity in the lateral direction is low, and since the joint part is formed of a pin, it is difficult to ensure the strength against the load.
In addition, since weight adjustment and height adjustment are integrated, it is difficult to adjust the physique and weight completely.
In other words, if the operator is not a standard physique, such as a person who is heavy and has a low sitting height, or vice versa, if the seat height is set according to the posture, the cushioning function is impaired. There is a problem that it is inconvenient.

Further, in the suspension seat structure known from Patent Document 1, since dampers having different configurations are arranged before and after the seat, it is necessary to individually adjust the dampers, and the damper arranged at the rear part is located outside the seat back. Therefore, if the inclination of the backrest is changed, the cushioning effect will be different.
Further, the suspension device in the driver's seat device known from Patent Document 2 has the above-described problems.

  The present invention has been made to solve such problems, and an object of the present invention is to provide a driving seat support device for a work vehicle having a configuration in which the suspension mechanism is compacted to improve the function and to take a comfortable driving posture. It is what.

  In order to achieve the above object, a driving seat support device for a work vehicle according to the present invention is supported by at least two shafts by a damper cylinder on an axis parallel to a vertical line passing through the shoulder of an operator seated on the seat, and is supported by the damper cylinder. A posture adjusting mechanism is interposed between the portion and the seat (first invention).

  According to a second aspect of the present invention, a driving seat is attached via a posture adjusting mechanism on a support plate supported by at least two damper cylinders at a driver seat installation location, and at least one of the damper cylinders receives magnetic fluid. It is characterized in that it is configured to perform a vibration damping function.

In the second invention, the damper cylinder that performs the damping function of the vibration using the magnetic fluid is preferably configured such that the buffer cylinder and the control cylinder that controls the vibration using the magnetic fluid are integrally formed (third invention). .
Here, as the magnetic fluid, a magnetorheological fluid (hereinafter referred to as MR fluid) can be suitably used.

  In the second and third inventions, the damper cylinder may have a double shaft slide support structure and a structure in which a coil spring is disposed inside or outside the shaft body of the double shaft (fourth). invention).

  In the second aspect of the present invention, it is preferable that the support plate supported by the damper cylinder is provided with a turning mechanism for the operation seat (fifth aspect).

According to the first aspect of the present invention, since the seat support portion can reduce the area occupied by the floor surface, the seated operator's feet can be widened and a comfortable driving posture can be achieved.
Moreover, the effect that the cleaning at the time of cleaning of the floor surface of the cab becomes easy is also obtained.

  According to the second aspect of the invention, in addition to the effects described above, the height can be adjusted independently of the weight adjustment of the sitting operator, the optimal height can be set, and a more comfortable driving posture. Can be taken. Also, by using MR fluid, the damping force of vibration can be set variably by changing the magnetic field, the damping force according to the body weight can be set in advance, and the effect of reducing the impact due to external force can be enhanced. .

  Further, by adopting the configuration of the third aspect of the invention, it is possible to reduce the installation space because it is structurally compact, and it is possible to take a comfortable driving posture while minimizing the occupied space at the foot.

  Further, according to the fourth invention, since the damper cylinder as a support body has a double-axis slide structure, only a smaller space is required and a load can be shared by a plurality of pieces, so that the backlash is rattled. A stable support force can be obtained.

  Furthermore, according to the fifth aspect, the turning mechanism can be attached to the support plate supported by the damper cylinder, so that the turning operation can be performed without impairing the cushioning function of the seat.

  Next, a specific embodiment of a driving seat support device for a work vehicle according to the present invention will be described with reference to the drawings.

[First Embodiment]
1 is a front view showing an embodiment of a driving seat support device for a work vehicle according to the present invention, FIG. 2 is a side view of FIG. 1, and FIG. 3 is a longitudinal sectional view of a damping function control damper. 4 shows a cross-sectional view of the main part of the damping function control damper cylinder, and FIG. 5 shows a vertical cross-sectional view of the support damper.

  The operation seat support device 1 of this embodiment includes two damper cylinders 50 and 30 installed upright from the floor surface 2 of the cab at a required interval, and a support panel 3 supported by the damper cylinders 50 and 30. It is comprised by the attitude | position adjustment means 40 provided on the movable support board 5 arrange | positioned through the turning mechanism 4 attached to this, and the driving | operation seat 6 attached via this attitude | position adjustment means 40.

One of the damper cylinders 50 and 30 is a damping function control damper 50 (hereinafter simply referred to as a damper cylinder 50) having an MR fluid control function, and the other is a support damper cylinder 30 (support damper).
A damper cylinder 50 having an MR fluid control function has a buffer cylinder 53 (of the present invention) fitted coaxially to a fixing member 51 having a mounting seat 52 for the floor 2 as shown in a cross section in FIG. Corresponding to a double-axis slide support structure), a coil spring 59 for restoring a damper disposed inside the fixed member 51, and a control cylinder for MR fluid that can control its operation in relation to the buffer cylinder 53 60, and a mounting seat plate 58 'for mounting the support plate 3 on the top of the buffer cylinder 53 is provided.

The buffer cylinder 53 is a cylindrical cylinder formed by combining a movable member 54 on the outside and a fixed member 51 on the inside.
The movable member 54 has a male screw portion 54b formed on the outer periphery of the upper end portion of the cylinder member 54a, and is coupled by being screwed into a female screw portion 54d formed on the inner peripheral surface of a hanging bowl-shaped base portion 54c. A female screw portion 54e is formed on the inner periphery of the lower end portion of the cylinder member 54a, and a lid member 54f having a male screw portion is screwed and fixed to the female screw portion 54e.
The cylinder volume 54a, the base 54c, and the lid member 54f regulate the internal volume of the cylinder to a required amount.

The buffer cylinder 53 is slidably assembled to the fixed member 51, and an annular protrusion 55 corresponding to a piston is integrally formed at an intermediate portion of the fixed member 51. A seal ring 55b is fitted in a groove portion 55a formed on the outer peripheral surface of the inner surface of the movable member 54 to contact the inner surface of the movable member 54 (cylinder member 54a), and a first chamber 56a and a second chamber 56b are formed vertically. Has been.
The inner circumferential surface of the cylinder member 54a located at the upper end of the first chamber 56a protrudes in a ring shape, and a seal ring 56c is fitted in a groove formed at the tip. Further, the screwing portion of the lid member 54f located at the lower end of the second chamber 56b is formed in a cylindrical shape, and seal rings 56d and 56e are fitted in grooves formed on the upper and lower sides on the inner peripheral surface thereof. ing. And the sealing performance of the 1st chamber 56a and the 2nd chamber 56b is ensured by these seal rings 56c and 56d and the seal ring 55b. Further, dust from the outside is prevented by the seal ring 56e.

The control cylinder 60 includes a cylindrical main body 61, and an upper lid member 63 and a bottom lid member 63 ′ that close a hole 62 that is opened on the upper and lower sides of the cylindrical main body 61.
Inside the cylindrical main body 61, an interior part 64 is disposed on the central axis of the cylindrical main body 61, and the upper and lower ends of the interior part 64 are joined and fixed to the cylindrical main body 61 and the bottom cover member 63 '.
The interior part 64 includes a gap forming part 64a made of a magnetic material such as electromagnetic soft iron, and a shaft part 64b made of a nonmagnetic material such as stainless steel press-fitted into the upper and lower ends thereof.
On the other hand, as shown in FIG. 4, a bobbin 61a made of a nonmagnetic material is embedded in the inner peripheral surface of the cylindrical main body 61 according to the position of the gap forming portion 64a, and around this bobbin 61a, A coil 61b configured by winding a lead wire is provided, and an end portion of the lead wire is connected to a controller provided outside the damper cylinder 50, and the viscosity of the MR fluid in which the bobbin 61a and the coil 61b flow in the cylinder It functions as an electromagnetic control means for controlling.

On the side surface of the cylindrical main body 61, through holes 65 are formed at two locations in the upper and lower sides, and the through holes 65 penetrate the inside and outside of the cylinder member 54 a via the cylindrical connecting member 66. The two through holes 54g are connected. One of the through holes 54g formed in the cylinder member 54a communicates with the first chamber 56a and the other communicates with the second chamber 56b.
Further, a buffer chamber 67 is formed below the upper lid member 63 so as to cope with expansion of the MR fluid due to a temperature change of the hermetically sealed MR fluid.

When the interior portion 64 is mounted in such a cylindrical main body 61, as shown in FIG. 4, the inside of the cylindrical main body 61 is partitioned into an upper chamber 62a and a lower chamber 62b with a gap forming portion 64a interposed therebetween. A gap S is formed between the inner surface of the main body 61 and the outer surface of the gap forming portion 64a. The gap S functions as a throttle for adjusting the flow rate of the fluid flowing between the upper and lower chambers 62a and 62b.
The interior of the control cylinder 60 and the buffer cylinder 53 having such a structure is filled with MR fluid (for example, iron carbonyl particles suspended in mineral oil-based oil).

  In contrast to such a damper cylinder 50, the other support damper cylinder 30 includes, as illustrated in FIG. 5, a columnar fixing member 31 having a mounting seat 32 at the lower end, and the fixing member 31. And a cylindrical movable member 34 provided with a seat plate that is fitted to the upper end portion and the support plate 3 is attached to the upper end portion thereof. And a coil spring 37 arranged concentrically so as to be in contact with the inner lower surface of the mounting cap member 35 of the movable member 34.

The fixing member 31 is a cylindrical body having a required size and is attached with a bottom end member 31a that closes the lower end portion. A mounting seat 32 is integrally attached to the bottom end member 31a, and the upper end portion is open. ing.
On the other hand, an annular member 34a is integrally attached to the upper end portion of the movable member 34, and a cap member 35 is screwed to the upper end portion of the annular member 34a to close the upper portion. A mounting seat plate 38 for supporting the support board 3 is integrally attached to the upper surface of the cap member 35.

  In addition, the fixed member 31 is concentrically matched with the inner peripheral portion of the annular member 34a of the movable member 34 and the inner peripheral portion 34b of which the inner peripheral portion of the lower end portion is reduced in diameter, and can be slid up and down. Thus, the bearings 36 and 36 'are integrally attached to each other.

As shown in FIGS. 1 and 2, the damper cylinders 50, 30 configured in this way are the operators when the operator Q sitting on the operation seat 6 supported by the shaft center is seated in a normal posture. The mounting seats 52 and 32 are mounted on the floor surface of the cab so as to substantially coincide with a vertical plane (vertical line C) passing through the shoulder Q ′ of Q and installed upright. Both the damper cylinders 50 and 30 support the support plate 3 having a size slightly larger than the width of the seat plate portion 6 a of the operation seat 6.
By doing in this way, since it will be supported by the damper cylinders 50 and 30 at a location that passes through a position that is almost close to the center of gravity of the operator Q seated on the operation seat 6, it is supported by two damper cylinders in the front, rear, left and right directions. The driving seat 6 can be reliably supported with a simple support structure without swinging.

A turning wheel (turning mechanism 4) is provided at the center of a line connecting the centers supported by the damper cylinders 50 and 30 in the support board 3, and a turning wheel (turning mechanism 4) is provided. The movable support board 5 is attached and supported so that turning is possible.
On the movable support board 5, a slide mechanism 41 and a height position adjustment mechanism 42 for adjusting the front / rear position of the operator are provided as posture adjustment means 40, and the operation seat 6 is attached via the height position adjustment mechanism 42. It has been.

  The slide mechanism 41 is disposed in the front-rear direction at a required interval in the left-right width direction, and the mounting base member 7 of the operation seat 6 is supported by the movable body. The slide mechanism 41 has a well-known structure, and the movable body can move intermittently back and forth along the rail so that the operator Q can adjust the front-rear position.

A height position adjusting mechanism 42 having a known structure is provided on the mounting base member 7, and a seat plate portion 6a of the operation seat 6 is formed on the seat mounting frame body on the upper side of the height position adjusting mechanism 42 by a known means. Is installed. As the height position adjusting mechanism 42, one that can be adjusted up and down by a cross link is employed. Note that a mechanism other than a cross link mechanism may be employed.
Reference numerals 8 and 8 'are consoles provided with an operation lever and an operation unit of equipment, etc., which are integrally attached to the mounting base member 7 with a bracket, and can be moved up and down and swivel together with the operation seat 6 so as to be positioned with the operator. It can be operated without changing the relationship. Reference numeral 6b in the figure denotes a backrest.

  The driving seat support device 1 of this embodiment is installed in a driving cab (not shown) of a work vehicle and supports the driving seat 6 as described above.

The operation seat support apparatus 1 of the present embodiment configured as described above can set the front / rear position by the slide mechanism 41 and the height position by the height position adjustment mechanism 42 when the operator sets the working posture. .
In addition, both damper cylinders 50 and 30 normally support the operation seat 6 while maintaining equilibrium with the stored energy of the coil springs 59 and 37, respectively.
In addition, vibration due to an external impact during operation is absorbed by the two damper cylinders 50 and 30 that support the seat, and one of the damper cylinders 50 is filled with MR fluid. Since the function of controlling the attenuation by the electromagnetic control means is provided, as described above, the controller receives a signal from a sensor for detecting vibration previously attached to the cab or the machine frame, By supplying a required amount of current to the coil 61b of the control cylinder 60 with an output signal obtained by comparison with preset data, the first chamber 56a and the second chamber 56 in the buffer cylinder 53 are supplied from the control cylinder 60 to the second chamber 61a. The pressure difference generated between the chamber 56b and the chamber 56b can be controlled to absorb the vibration quickly and to exert the damping function.
In the other damper cylinder 30 for support, the shock is mitigated by following the vibration damping buffer function of the damper cylinder 50 by a cushion function by a coil spring 37 provided inside the movable member 34 with respect to the fixed member 31. Demonstrate the function. Therefore, even when a large shock is received, vibration is quickly absorbed and buffered.

The vibration damping action of the damper cylinder 50 will be described. When receiving vibration from the vehicle body side, the movable member 54 is displaced in the axial direction with respect to the fixed member 51. For example, when the movable member 54 moves downward in the vertical direction against the urging force of the coil spring 59, the cylinder member 54a on the movable member 54 functions to push down the MR fluid in the first chamber 56a.
As shown in FIG. 4, the MR fluid in the first chamber 56 a is pushed out to the upper chamber 62 a of the control cylinder 60 through the through hole 54 g, the connecting member 66, and the through hole 65 by a pressing action. At this time, since the second chamber 56b on the buffer cylinder 53 side is in a decompressed state, the MR fluid passes from the lower chamber 62b of the control cylinder 60 through the through hole 65, the connecting member 66, and the through hole 54g to the second chamber 56b. Is sent.

In this manner, the fluid in the first chamber 56a is moved to the upper chamber 62a in the control cylinder 60 by the lowering operation of the movable member 54 in the buffer cylinder 53, so that the pressure in the second chamber 56b opposite to this is lowered. The pressure in the lower chamber 62b of the control cylinder 60 connected to this through the through hole 65, the connecting member 66, and the through hole 54g also decreases.
Therefore, in the control cylinder 60, the upper chamber 62a is in a pressurized state and the lower chamber 62b is in a reduced pressure state, so that the filled MR fluid flows from the upper chamber 62a toward the lower chamber 62b due to the pressure difference. become.
At this time, the flow rate is reduced in the gap S between the outer surface of the gap forming portion 64a that divides the upper chamber 62a and the lower chamber 62b and the inner surface of the cylindrical main body 61.

  For the fluid passing through the gap S, a vibration detection signal from the sensor (not shown) provided on the machine body side is sent to the controller at this time, and the coil 61b is required based on preset data. The magnetic field corresponding to the current is formed between the gap forming portion 64a made of a magnetic material and the cylindrical main body 61, and the flowing MR fluid is excited, and the viscosity of the MR fluid is excited by the excitation of the MR fluid. Changes. In other words, the fluidity of the MR fluid varies in proportion to the strength of the magnetic field.

In a state where the movable member 54 moves upward, the MR fluid flows between the control cylinder 60 and the buffer cylinder 53 by the operation opposite to the above-described operation, and the state of the flow is controlled.
By changing the flow state of the MR fluid, the vertical movement speed of the buffer cylinder 53 is controlled by changing the flow resistance at the time of flow, and the received shock is alleviated.

For example, in the case of a driver's seat in a driver's cab provided in a bulldozer, when the vehicle is reversely moved, a large shock such as climbing over a rock or a large protrusion is applied. When the control means makes the amount of current applied from the controller larger than usual so that the strength of the magnetic field formed between the cylindrical main body 61 and the gap forming portion 64a increases proportionally. The apparent viscosity of the MR fluid flowing through the gap S is increased, the flow resistance in the gap S is increased, and the moving speed of the movable member 54 is decreased.
That is, a cushioning function is provided in which a soft spring property is given to a sudden shock and the shock is buffered by a soft buffering action, and a vibration that follows the shock is given a damping force by the control cylinder 60 to suppress a vibration motion. It can be demonstrated.

  For small continuous shocks when traveling on rough terrain, a control signal is transmitted from the controller to the coil 61b in the direction of decreasing the magnetic field strength by a detection signal from the sensor, and the electromagnetic control is performed. If the magnetic flux density to the MR fluid in the control cylinder 60 is lowered by the action of the means, the flow resistance is lowered, and the fluidity of the MR fluid is increased contrary to the above operation, so that the movable in the buffer cylinder 53 is movable. The amount of movement of the member 54 in the axial direction is relaxed, and a vibration absorbing action without a jerky feeling can be obtained.

In contrast to the damper cylinder 50 that exhibits such a function, the other damper cylinder 30 has a support function with a simple structure including a buffering coil spring 37 inside, as described above. The damping function is mainly performed by the damping function control damper 50, and as a damper cylinder that supports the operating seat 6 as a whole, the damping function is performed in conjunction with the operation of the damper cylinder 50.
Therefore, the operation seat 6 is smoothly buffered against vibrations by the damper cylinders 50 and 30 to ensure comfort.

  As described above, the driving seat support device 1 of the present embodiment allows the vibration buffering device to perform the buffering action by a mechanism completely different from the seat height position adjusting mechanism 42, so that adjustment based on body weight is performed. Since the position adjustment according to the other physiques can be performed without needing to exhibit an effective buffer function in the optimum state, the operator can comfortably perform the driving operation. In addition, there is an advantage that the seat can be widened and the problem that there is no space in the foot as in the conventional support device can be solved, and the driving can be continued in a free posture.

[Second Embodiment]
Next, a second embodiment, which is another embodiment of the present invention, will be described with reference to FIG.
The present embodiment is different in that the structure of the damping function control damper cylinder 50 is changed in the operation seat support device 1 according to the first embodiment described above. In the following description, the description of the same parts or the like as those already described will be omitted or simplified.

  The damper cylinder 10 having the MR fluid control function according to the second embodiment is coaxially fitted to the fixing member 11 having the mounting seat 12 with respect to the floor surface 2 as shown in FIG. The buffer cylinder 13 (corresponding to the double-axis slide support structure of the present invention), the damper restoring coil spring 19 disposed inside the fixed member 11, and the operation of the buffer cylinder 13 can be controlled in relation to the buffer cylinder 13. And a mounting seat plate 18 ′ for mounting the support plate 3 on the top of the buffer cylinder 13.

The buffer cylinder 13 is a cylindrical cylinder formed by combining a movable member 14 on the outer side and a fixed member 11 on the inner side. The movable member 14 has an annular thick member 14b integrally coupled to the upper end portion of the cylinder member 14a, an annular head member 14c is screwed to the lower end portion, and is fixed to the upper end portion of the cylinder member 14a. The inner volume of the cylinder is regulated to a required amount by the inner lower end of the member 14b and the inner upper end of the head member 14c.
The buffer cylinder 13 is slidably assembled to the fixed member 11, and an annular projecting portion 15 corresponding to a piston is integrally formed at an intermediate portion of the fixed member 11. A seal ring 15b is fitted in a groove portion 15a formed on the outer peripheral surface of the first and second chambers 16a and 16b in a front and rear direction by contacting the inner surface of the movable member 14 (cylinder member 14a). ing. A seal ring 16d is fitted in each of the first chamber 16a and the second chamber 16b to restrict fluid leakage from the cylinder.

  The annular member 14b and the head member 14c that are attached to the movable member 14 are provided with bearing bushes 17 that are guided by the fixed member 11, and the movable member 14 is aligned with the shaft center by the bearing bushes 17. Can be slid up and down and can stably support the load applied to the support plate 3. Accordingly, it is preferable that the mounting positions of the bearing bushes 17 and 17 are spaced apart as much as possible. Further, a seal member 17 ′ is fitted outside the fitting position of the bearing bush 17 so that the chambers 16 a and 16 b are kept watertight with respect to the outside. A cap member 18 is screwed onto the annular member 14 b and a mounting seat plate 18 ′ for mounting the support plate 3 is mounted on the cap member 18 at the top of the buffer cylinder 13 thus configured. .

  On the other hand, the control cylinder 20 is formed in a body 21 having a required size with a hole 22 having a required inner diameter passing through the inside thereof in the vertical direction, and an upper lid member 23 provided so as to close both ends of the through-hole 22. There is a bottom lid member 23 '. Between the upper lid member 23 and the bottom lid member 23 ′, there is a support member comprising a coil portion 25 and a sleeve 24 a, and the upper and lower sides of the support shaft are not fitted so that the coil portion 25 comes to an intermediate position of the support member. It arrange | positions so that it may be supported by the sleeve 24a which consists of magnetic materials.

  A slight gap “a” is formed between the inner peripheral surface of the main body 21 and the outer periphery of the bobbin 25 a constituting the coil portion 25. Further, a lead wire 27 is connected to the coil 25b constituting the coil portion 25 so as to be electrically controlled by being connected to a controller (not shown), and the coil 25b serves as a winding core of the winding portion of the coil portion 25. An electromagnetic wave is attached to a bobbin 25a made of a cylindrical magnetic material, and the gap a between the bobbin 25a and the inner peripheral surface of the cylinder member 26 is kept small to cause flow resistance of the MR fluid. Control means is configured. The main body 21 is made of, for example, electromagnetic soft iron, and the magnetic field is strongly formed in the range of the bobbin 25a.

  The body 21 has through holes 28a and 28b communicating with the first chamber 16a and the second chamber 16b inside the cylinder 14a of the buffer cylinder 13 at positions appropriately separated from the cylinder member 26. Respectively provided, MR fluid is communicated from the control cylinder 20 to the buffer cylinder 13. In addition, a buffer chamber 29 filled with a gas such as air is provided at the top of the control cylinder 20 so that it can cope with expansion due to a temperature change of the MR fluid. MR fluids (for example, iron carbonyl particles suspended in mineral oil-based oil) are filled and enclosed in the chambers inside the control cylinder 20 and the buffer cylinder 13 thus formed.

As shown in FIG. 7, the electromagnetic control means for causing the flow resistance of the MR fluid in the control cylinder 20 is connected to the cylinder member of the control cylinder 20 and the coil portion 25 located therein, and in addition, leads to the coil portion 25. It comprises a known controller (not shown) connected by a line 27. The coil portion 25 is energized by a lead wire 27 with a controller interposed.
In the electromagnetic control means, a signal from a sensor that detects vibrations arranged in a driver's cab or the like (not shown) is controlled by a controller, and the bobbin 25a and the main body are caused to flow a required amount of current through the coil portion 25 by the output signal. When the MR fluid moves through a narrow gap a formed between the bobbin 25a and the inner wall of the main body 21, the apparent viscosity (flow) in the magnetic field is changed. The vibration control function can be controlled by changing the flow resistance by changing the property.
Even when the damper cylinder 10 according to the second embodiment is applied to the operation seat support device, the same operational effects as those described in the first embodiment can be obtained.

[Third Embodiment]
Next, FIG. 8 is a cross-sectional view showing a third embodiment of the damping function control damper cylinder.

  The damping function control damper cylinder (simply referred to as damper cylinder 10A) of this embodiment is similar in basic configuration to that of the above-described embodiment, but has a different combination structure. Accordingly, basic operational effects are the same as those of the above-described embodiments. In addition, components other than those that exhibit particularly different functions are denoted by the same reference numerals as those of the above-described embodiment, and detailed description thereof is omitted.

In the damper cylinder 10A of this embodiment, a control cylinder 20A is incorporated in the center of the buffer cylinder 13A.
Further, a restoring coil spring 19A is disposed between the mounting seat 12A provided at the lower end of the fixed member 11A and the mounting seat plate 18a provided at the upper end of the movable member 14A outside the buffer cylinder 13A.
The buffer cylinder 13A is configured by combining a fixed member 11A having a mounting seat 12A and a movable member 14A that slides in the axial direction on the inside thereof.

The fixing member 11A constituting the buffer cylinder 13A includes a mounting seat 12A at the lower portion, and the head member 11b is screwed and fixed to the upper end portion of the cylinder member 11a, which is the main body of the fixing member 11A, at the upper end portion.
The lower member 11c is fixed to the lower end portion of the cylinder member 11a, and the annular projecting portion 15A on the movable member 14A side is slidably positioned between the upper end of the lower member 11c and the lower end of the head member 11b. Thus, the first and second chambers 16a and 16b are partitioned by the annular projecting portion 15A.

On the other hand, the movable member 14A is fitted into the fixed member 11A so as to be slidable coaxially, and its upper end protrudes from the upper end of the fixed member 11A by an appropriate amount and is integrally formed with the screw cap 18A at the top. A mounting base plate 18a for supporting the support board 3 is attached, and a cylindrical body with a screwed lid 14e attached to the lower end, which serves as a piston and a rod.
The annular projecting portion 15A is formed on the outer periphery of the intermediate portion of the movable member 14A, the groove portion 15a is formed on the outer periphery thereof, and the seal ring 15b is fitted therein, and contacts the inner peripheral surface of the cylinder member 11a of the fixed member 11A. Thus, a third chamber 16f and a fourth chamber 16g are formed in the cylinder.
Further, a control cylinder 20A is coaxially fitted inside the movable member 14A.

The control cylinder 20A has a support member consisting of a coil portion 25 and a sleeve 24a at the center, and a lower end screwed into a shaft support hole 14f provided on the upper surface side of the lid 14e, and an upper end inside the movable member 14A. A cylinder member 26A made of electromagnetic soft iron is fixed to the shaft hole 14f 'at the center of the lower surface of the support piece fitted to the outer side of the support member, and both ends thereof are supported by the screwed lid 14e. It is held concentrically by the piece 14h. A coil portion 25 is provided at an intermediate position with a slight gap from the inner peripheral surface of the cylinder member 26A made of electromagnetic soft iron and supported by a sleeve 24a made of a nonmagnetic material at the top and bottom.
A bobbin 25a made of a magnetic material is disposed on the winding portion of the coil portion 25 so as to be a winding core, and a narrow gap portion a is formed between the inner peripheral surface of the cylinder member 26A. ing. A lead wire 27 connected to a controller (not shown) is connected to the coil 25b of the coil portion 25 through the inside of the support member, and a necessary current controlled by the controller is supplied by the lead wire 27. It has become.

  Further, on the outer periphery of the cylinder member 26A of the control cylinder 20A, the inner periphery of the annular projecting portion 15B projecting inward from the inner peripheral portion of the movable member 14A is fitted into a groove portion 15c provided on the peripheral surface. The third ring 16f and the fourth chamber 16f are separated from each other by the annular projecting portion 15B between the cylinder member 26A and the inner periphery of the movable member 14A. The chamber 16g is formed.

A through hole 14j through which the first chamber 16a and the third chamber 16f communicate on the upper side and the lower side with the inner and outer annular projecting portions 15A and 15B of the movable member 14A as a boundary, a second chamber 16b, and a fourth chamber 16g. Through which the third chamber 16f and the upper chamber 22a in the control cylinder 20A communicate, and the fourth chamber 16g and the bottom in the control cylinder 20A. A through hole 26b that communicates with the side chamber 22b is provided.
These chambers are filled with MR fluid. In addition, a seal ring is provided on the inner peripheral upper end of the head member 11b and the lower peripheral end of the lower member 11c, which are positioned above the fixed member 11A, so that the inside of the cylinder can be kept watertight.

  The damper cylinder 10A configured as described above is arranged in the same manner as in the above embodiment, and the controller 25 causes the coil portion 25 of the control cylinder 20A to be excited. Therefore, the function is the same as that of the above embodiment.

The flow state of the MR fluid will be described. When the movable member 14A is pushed down, the annular protrusions 15A and 15B are lowered, and the fluid in the second chamber 16b is pressurized on the buffer cylinder 13A side, and the through hole 14k. From the fourth chamber 16g to the lower chamber 22b of the control cylinder 20A through the through hole 26b. On the other hand, the first chamber 16a and the third chamber 16f in the buffer cylinder 13A are in a reduced pressure state, so that the fluid in the upper chamber 22a in the control cylinder 20A communicated by the through hole 14j is a third pressure difference. It flows from the chamber 16f to the first chamber 16a.
Therefore, in the control cylinder 20A, the MR fluid flows from the lower chamber 22b through the gap a to the upper chamber 22a due to a pressure difference between the lower chamber 22b and the upper chamber 22a.
The controller controls a signal from a vibration detection sensor (not shown) installed on the airframe side with respect to the MR fluid flowing in the gap portion a based on the data, and a required current is supplied to the coil portion 25 by the lead wire 27. The flow resistance is controlled by generating a magnetic field corresponding to the supplied current around the bobbin 25a to change the fluidity of the MR fluid, and as a result, the moving speed of the buffer cylinder 13A is controlled.

  In the above description, a configuration is described in which two damper cylinders for supporting the operation seat are arranged. However, if necessary, another damper cylinder may be arranged on the front side or the rear side in addition to the above. it can. In this way, it is possible to cope with a case where a large load is applied to the front side or the rear side of the operation seat.

The front view showing one Embodiment of the driving | operation seat support apparatus of the working vehicle concerning this invention. The side view of FIG. Sectional drawing of a damping function control damper. Sectional drawing of the principal part of a damping function control damper. The longitudinal cross-sectional view of a support damper. Sectional drawing showing other embodiment of a damping function control damper cylinder. The principal part sectional drawing of the damping function control damper cylinder which concerns on other embodiment. Sectional drawing showing other embodiment of a damping function control damper cylinder. The side view (a) showing one embodiment of the conventional support structure of a driving seat, and the figure (b) seen from the front side of the seat

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Driving | running seat support apparatus, 3 ... Supporting board, 4 ... Turning mechanism, 5 ... Movable support board, 6 ... Seat, 10, 10A, 50 ... Damper cylinder, 11, 11A, 51 ... Fixed member, 12 ... Mounting seat, 13, 13A, 53 ... buffer cylinder, 14, 14A, 54 ... movable member, 14a ... cylinder member, 15, 15A, 15B ... annular projection, 16a, 56a ... first chamber in the buffer cylinder, 16b, 56b ... Second chamber in the buffer cylinder, 16f ... Third chamber in the buffer cylinder, 16g ... Fourth chamber in the buffer cylinder, 17 ... Bearing bush, 18 ', 18a ... Mounting seat plate, 19, 19A, 37 ... Coil spring, 20, 20A, 60 ... Control cylinder, 21 ... Main body, 24a, 61a ... Sleeve, 25 ... Coil part, 25b, 61b ... Coil, 25a ... Bobbin, 26, 26A ... Cylinder member, 2 ... leads, 28a, 28b, 14j, 14k, 26a, 26b ... hole, 30 ... supporting the damper cylinder, 31 ... fixing member, 32 ... mounting seat, 34 ... movable member.

Claims (5)

  At least two shafts are supported by a damper cylinder on an axis parallel to the vertical line passing through the shoulder of the operator sitting on the seat, and a posture adjusting mechanism is interposed between the support portion by the damper cylinder and the seat. A driving seat support device for a working vehicle.   A driver's seat is attached via a posture adjusting mechanism on a support plate supported by at least two damper cylinders at the driver's seat installation location, and at least one of the damper cylinders has a vibration damping function using magnetic fluid. An operation seat support device for a work vehicle, characterized in that the operation seat support device is configured to be performed.   The operation seat support device for a work vehicle according to claim 2, wherein the damper cylinder that performs a vibration damping function using a magnetic fluid is configured integrally with a buffer cylinder and a vibration suppression control cylinder using the magnetic fluid.   The operation seat support device for a work vehicle according to claim 2 or 3, wherein the damper cylinder has a double shaft slide support structure, and a coil spring is disposed inside or outside the shaft body of the double shaft. .   The driving seat support device for a work vehicle according to claim 2, wherein a driving seat turning mechanism is provided on the support plate supported by the damper cylinder.

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