JP2009209629A - Work operating device for work vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a work operating device for a work vehicle, which can continuously operate a work device without causing a malfunction or an inoperable state. <P>SOLUTION: According to the structure of the work operating device, an ATT pilot valve 28 for operating an ATT control valve is provided with an ATT operating pedal 27, and an ATT lock device 31 that can fix the ATT pilot valve 28 within an operation limit of the ATT operating pedal 27. The ATT lock device 31 is formed of: a lock receiving portion 31A for operating the ATT pilot valve 28; a lock operating portion 31B having a lock operating lever 45 for rotating an operating member 44 around an axis of a spindle 43 and between a released position O and a locked position R, and a lever locking mechanism 46 for locking the operating member 44 between the released position O and the locked position R; and a wire cable 51 connecting between the lock operating portion 31B and the lock receiving portion 31A in interlock with each other. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a work operation device capable of continuously operating a work drive device in a work vehicle such as a skid steer loader equipped with a work device.

For example, Patent Document 1 discloses a pedal that can be operated continuously by providing a pedal lock mechanism and a lock release mechanism that can lock an operation pedal at an arbitrary position on an operation pedal that performs cargo handling. The pedal lock mechanism and the unlock mechanism include a ratchet tooth attached to the fixed side, a ratchet pawl attached to the operation pedal and freely detachable from the ratchet tooth, and a restraining spring that biases the ratchet pawl in the engaging direction. And a push rod for driving the ratchet claw in the disengagement direction via the link.
JP-A-1-203527

  However, with the left or right leg, the push rod protruding from the upper surface of the operation pedal is stepped on and pushed to lock the operation pedal, or the leg is separated from the push rod to unlock the operation pedal. Therefore, at work sites, mud or the like is likely to adhere to the shoes that step on the operation pedal, and mud may adhere to the operation pedal or the push rod, resulting in erroneous operation or inoperability of the push rod.

  The present invention solves the above problems and provides a work operation device for a work vehicle that can be easily locked in a state where an operation pedal is depressed and a work device can be continuously driven without causing an erroneous operation or inoperability. For the purpose.

  The invention described in claim 1 is a work operation device for a work vehicle that supplies and discharges hydraulic oil discharged from a hydraulic pump to a work drive device via a work control valve, and drives the work device. It is of a pilot hydraulic type, and a work pilot valve that supplies and discharges pilot hydraulic fluid to the work control valve is provided, a work operation pedal that operates the work pilot valve is provided, and the work pilot valve is operated, and the operation control pedal operation limit A work operation lock device capable of locking the work pilot valve in the operation operation lock device, and an operation member that is rotated between a release position and a lock position around a spindle axis by the lock operation lever, and the operation Lock operation unit having a lever locking mechanism for locking a member at a release position and a lock position It is obtained by providing a lock driven mechanism for operating the work pilot valve, and a lock interlocking member operatively connected to a lock operating portion and the lock-driven mechanism.

  According to a second aspect of the present invention, in the configuration according to the first aspect, the lever locking mechanism includes a support member fixed to the vehicle body and facing the operation member, and one of the facing portions of the support member and the operation member. A locking sphere partially projecting at a predetermined position, and a mechanism provided at a predetermined position on the other facing portion to engage the protruding portion of the locking sphere at the release position and the lock position to lock the operation member. A stop recess and an urging member that presses the operation member against the support member are provided.

  According to the first aspect of the present invention, the operation locking device is provided with a lever lock that locks the operation member, which is rotated between the release position and the lock position by the lock operation lever, between the release position and the lock position. Since the mechanism is provided, there is no erroneous operation or inoperability with a simple structure, the work pilot valve can be securely locked at the operation limit of the lock operation lever, the work drive device can be continuously driven, and the work device can be continuously operated. It can be done without mistakes or inoperability. In addition, with a simple structure, it can be easily and inexpensively added to an existing work pilot valve operated by an operation pedal.

  According to the configuration of the second aspect, in the lever locking mechanism, the operating member is pressed against the support member by the biasing member, and the protruding portion of the locking sphere is fitted into the locking recess, thereby releasing the operating member. And the locking position, the operation member can be locked with a simple structure, and the releasing operation for releasing the locking sphere from the locking recess can be easily performed.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[Embodiment]
As shown in FIG. 5, in this work vehicle, a work device 3 is provided at the front of a vehicle body 1 having a pair of left and right front wheels 2F and a pair of left and right rear wheels 2R. In this working device 3, a pair of left and right working booms 4 extending forward are supported on both sides of the rear portion of the vehicle body 1 so as to be swingable in the vertical direction, and a boom cylinder 5 connected to the vehicle body 1 and the tip side of the working boom 4. As a result, the work boom 4 is swung vertically. And the fixture 6 is supported at the front-end | tip part of the work boom 4 so that rotation is possible up and down, and the fixture 6 is rotated up and down by the bucket cylinder 7 connected between the work boom 4 and the fixture 6. FIG. The In normal use, a bucket is attached to the fixture 6, but here, instead of the bucket, a rotary brush device 8 for leveling, which is a work attachment (ATT), is attached. The rotary brush device 8 is provided with an ATT drive motor 8b which is a hydraulic work drive device in a cover 8a and a rotary brush 8c which is driven to rotate around a horizontal axis by the ATT drive motor 8b. The rotary brush device 8 is lifted and lowered by the cylinder 5 via the work boom 4, and the grounding posture of the rotary brush device 8 is adjusted by the bucket cylinder 7 via the fixture 6.

  As shown in FIG. 4, the vehicle body 1 includes a hydraulic travel drive device 10 driven by an engine 9 and a hydraulic work drive device 20 that drives a boom cylinder 5, a bucket cylinder 7, and an ATT drive motor 8b, respectively. Is provided.

  The hydraulic travel drive device 10 includes left and right hydraulic travel pumps 11R and 11L connected to the output shaft of the engine 9, and the travel pumps 11R and 11L via left and right closed loop circuits 13R and 13L, respectively. The left and right traveling motors 12R and 12L are connected, and the left traveling motor 12L rotates the left front and rear wheels 2F and 2R through the speed reducer, and the right traveling motor 12R reduces the speed reducer. The right front and rear wheels 2F and 2R are each driven to rotate through the wheel. The left and right traveling pumps 11R and 11L are respectively operated in the discharge direction and the discharge amount via a pilot valve (not shown) by a left and right steering lever (not shown) or a joystick lever arranged only on the left side. A variable displacement type axial piston pump is used, and for example, constant displacement type orbit motors (torque motors) are used as the traveling motors 12R and 12L. The left and right front and rear wheels 2F and 2R are rotated by the left and right steering levers. Steering with controlled direction and rotational speed.

  The hydraulic work drive device 20 includes a main pump 21 and a sub pump (hydraulic pump) 22 connected to the output shaft of the engine 9, and a boom cylinder 5, a bucket cylinder 7, and an ATT drive motor 8 b by hydraulic oil of the main pump 21. Each has a work controller 23 that controls driving. This work controller 23 supplies a boom control valve 24 for supplying and discharging hydraulic oil to the boom cylinder 5, a bucket control valve 25 for supplying and discharging hydraulic oil to the bucket cylinder 7, and supplies hydraulic oil to the ATT drive motor 8b. It has an ATT control valve (work control valve) 26 for discharging.

  The ATT control valve 26 is a pilot hydraulic type, and is operated by an ATT pilot valve (work pilot valve) 28. An ATT operation pedal (work operation pedal) 27 for operating the ATT pilot valve 28 is disposed on the floor portion of the cockpit. Has been. The ATT pilot valve 28 is provided with an ATT lock device (work operation lock device) 31 that can lock the ATT pilot valve 28 with an operation limit of the ATT operation pedal 27.

The ATT pilot valve 28 and the ATT locking device 31 will be described with reference to FIGS.
As shown in FIG. 2, the ATT pilot valve 28 includes two front and rear spool valves 28F and 28R, and when the ATT operation pedal 27 is stepped forward or backward, the tilt cam 29 is moved back and forth about the horizontal axis 29a. The spool valves 28F and 28R can be operated by tilting. That is, as shown in FIG. 2 (a), in the neutral posture in which the ATT operation pedal 27 is not depressed, the spool valves 28F and 28R are in the neutral (off) position, and the pilot hydraulic oil discharged from the sub pump 22 is released from the relief valve 28T. Is returned to the tank T. When the ATT operation pedal 27 is stepped forward to the forward operation posture, the spool of the front spool valve 28F is pushed by the tilt cam 29 via the push rod and the adjustment spring, as shown in FIGS. 2 (b) and 2 (c). The supply port Pi and the front discharge port Pf are connected to each other, the pilot hydraulic oil is sent to one pilot portion 26a of the ATT control valve 26, and the pilot hydraulic oil discharged from the other pilot portion 26b is supplied to the rear discharge port Pr. From the discharge port Po to the tank T through the rear spool valve 28R. As a result, the ATT control valve 26 is switched, and the hydraulic oil supplied from the main pump 21 is sent to the ATT drive motor 8b to be driven forward. On the contrary, in the backward operation posture in which the ATT operation pedal 27 is depressed backward, the spool of the rear spool valve 28R is pushed in, the supply port Pi and the rear discharge port Pr are connected, and the pilot hydraulic oil is supplied to the other side of the ATT control valve 26. The pilot hydraulic oil sent to the pilot portion 26b and discharged from one pilot portion 26a is returned from the front discharge port Pf to the tank T from the discharge port Po via the front spool valve 28F. As a result, the ATT control valve 26 is switched, and the hydraulic oil supplied from the main pump 21 is sent to the ATT drive motor 8b to be driven in reverse.

  The ATT lock device 31 includes a lock passive part 31A for operating the ATT pilot valve 28, a lock operation part 31B installed in the cockpit, and a lock interlocking member 31C for interlockingly connecting the lock operation part 31B and the lock passive part 31A. It is configured.

  As shown in FIGS. 1 and 2, the lock passive portion 31 </ b> A extends downward from the ATT operation pedal 27 and is tilted about the horizontal axis 29 a in conjunction with the ATT operation pedal 27 (valve operation member). ) 32 and the ATT pilot valve 28 can be operated by the lock passive lever 32 via the tilt cam 29.

  As shown in FIGS. 1 and 3, the lock operation unit 31 </ b> B is provided with a support plate (support member) 42 attached to the fixing member 41 of the cockpit (vehicle body 1), and is protruded horizontally from the support plate 42. A support shaft (bolt in the figure) 43, an operation member 44 fitted to the support shaft 43 through a center hole 44c so as to be rotatable and slidable, and a fixed end portion attached to the operation member 44. A lock operation lever 45 and a lever locking mechanism 46 for locking the operation member 44 at the release position O and the lock position R are provided. The operation member 44 has a circular operation plate 44a facing the support plate 42, and a sleeve 44b integrally attached to the axial center of the operation plate 44a, and a lock drive lever 49 is attached to the sleeve 44b. ing.

  The lever locking mechanism 46 is rotatably supported by one of the support plate 42 and the operation plate 44a, and is a locking sphere 46a that contacts the other, and a biasing coil that biases the operation plate 44a toward the support plate 42. A spring (biasing member) 46b and a locking recess 46c formed on the other of the support plate 42 and the operation plate 44a and engaged with the locking sphere 46a are provided. That is, for example, storage recesses are formed at predetermined plural positions (in the figure, at four positions every 90 ° around the support shaft 43) on the outer surface of the operation plate 44a (facing side of the support plate 42). The locking sphere 46a is rotatably held so that a part protrudes. On the other hand, the support plate 42 is formed with a locking recess 46c into which the protrusion of the locking sphere 46a can be engaged at a position corresponding to the release position O of the lock operation lever 45 and a position corresponding to the lock position R. ing. An adjustment nut 47 for pressure adjustment is attached to the male thread portion 43a formed on the distal end side of the support shaft 43, and the operation plate 44a is attached to the support plate 42 side between the adjustment nut 47 and the sleeve 44b. An energizing coil spring 46 b is externally fitted to the support shaft 43. Therefore, the operating member 44 is urged toward the support plate 42 by the urging coil spring 46b, and the protruding portion of the locking sphere 46a is engaged with the locking recess 46c at the release position O and the lock position R, respectively. The operation member 44 and the lock operation lever 45 can be locked. Further, when the operation is started, the lock operation lever 45 is slightly swung in the axial direction of the support shaft 43, so that the operation plate 44a is tilted within the range of play between the support shaft 43 and the center hole 44c of the operation member 44. The protruding portion of the locking sphere 46a can be detached from the locking recess 46c, and the lock operation lever 45 can be easily operated.

  Further, a stopper mechanism 48 that restricts the rotation of the operation member 44 at the release position O and the lock position R is provided. The stopper mechanism 48 includes a restricting piece 48a provided at a predetermined position on the outer peripheral portion of the operation plate 44a of the operation member 44, and a pair of stopper members 48b provided on the support plate 42 to restrict the movement of the restricting piece 48a. An adjustment bolt capable of adjusting the restriction position is used for the stopper member 48b.

  Further, a guide hole 41b in the vertical direction for guiding the rotation of the lock operation lever 45 between the release position O and the lock position R is formed in the front plate portion 41a of the fixing member 41, and a buffer rubber is provided in the guide hole 41b. A ring 41c is attached.

  As shown in FIGS. 1 to 3, the lock interlocking member 31C includes a wire cable 51 connected from the lock operation portion 31B to the lock passive portion 31A, and the wire cable 51 is slidable in the cable cover 51b. It is stored in. In the lock operation portion 31B, the proximal end portion of the wire 51a is connected to the free end portion of the lock drive bar 49, and in the lock passive portion 31A, the distal end portion of the wire 51a is connected to the free end portion of the lock passive lever 32. 33 are connected.

  In the lock passive portion 31A, a tip cable fixing tool 35 for fixing the tip portion of the cable cover 51b is provided on the valve support plate 34 attached to the ATT pilot valve 28. The wire connector 33 has an engagement plate 33b having an elongated hole 33c into which a pin 33a protruding from the free end of the lock passive lever 32 is movably fitted, and the tip of the wire 51a is connected to the connector Is connected to the engagement plate 33b. A restraining coil spring 33d is connected between the bracket 34a of the valve support plate 34 and the engagement plate 33b to urge the wire 51a toward the distal end side, whereby the lock drive bar 49 and the operation member 44 are used. The lock operation lever 45 is urged to rotate toward the release position O.

  When the lock operation lever 45 is locked at the release position O, the pin 33a is fitted in the wire connector 33 so as to be movable in the front-rear direction from the middle position of the elongated hole 33c. The stepping forward and backward of the vehicle is not restricted. When the lock operation lever 45 is rotated to the lock position R, the pin 33a is locked to the front end portion of the elongated hole 33c of the engagement plate 33b to tilt the lock passive lever 32, and the front spool valve 28F is operated. The

  In the lock operation portion 31B, a base end side cable support 41d is attached to the fixing member 41 fixed to the vehicle body 1, and the base end portion of the cable cover 51b of the wire cable 51 is fixed to the base end side cable support 41d. A proximal cable fixture 50 is provided.

  In the above configuration, when the rotary brush device 8 is mounted on the fixture 6 and the leveling work is performed, the boom brush 5 and the bucket cylinder 7 are operated to adjust the height and posture of the rotary brush device 8 to adjust the rotary brush 8c. Ground. Then, in order to drive the rotating brush device 8 and perform leveling work on the ground contact surface, the ATT operation pedal 27 is stepped forward, the ATT pilot valve 28 is operated, and the pilot hydraulic oil is supplied to and discharged from the pilot portions 26a and 26b. The ATT control valve 26 is switched and hydraulic oil is supplied from the main pump 21 to the ATT drive motor 8b to drive the rotary brush 8c in the normal direction.

  When performing leveling work by continuously operating the rotating brush device 8, the lock operating lever 45 of the ATT lock device 31 is rotated from the release position O to the lock position R against the restraining coil spring 33d to lock the lever. The lock operation lever 45 is locked at the lock position R by fitting the lock sphere 46a of the mechanism 46 into the lock recess 46c. Thus, the lock passive lever 32 is driven via the wire cable 51, the ATT pilot valve 28 is operated via the tilt cam 29 to switch the ATT control valve 26, and the hydraulic oil from the main pump 21 is supplied to the ATT drive motor 8b. To supply continuously. As a result, the rotary brush 8c of the rotary brush device 8 can be continuously forward-rotated without continuing to step on the ATT operation pedal 27. When stopping the rotation of the rotating brush 8c, the lock operating lever 45 is slightly tilted in the axial direction of the support shaft 43 to disengage the locking sphere 46a from the locking recess 46c, and is locked by the restraining coil spring 33d. The operation lever 45 is returned from the lock position R to the release position O.

  According to the above-described embodiment, the ATT lock device 31 that operates the ATT pilot valve 28 is provided with the lock passive portion 31A that operates the ATT pilot valve 28 and the release position O around the axis of the support shaft 43 by the lock operation lever 45. And a lock operation portion 31B having a lever locking mechanism 46 for locking the operation member 44 between the release position O and the lock position R. Since the lock driving lever 49 of the portion 31B and the lock passive lever 32 of the lock passive portion 31A are interlocked and connected by the wire cable 51, the lock operating lever 45 can be easily moved to the lock position R and the release position O by the lever locking mechanism 46, respectively. And the ATT pilot valve 28 can be locked at the operation limit, and the ATT drive motor 8b is continuously driven. Rukoto can. Since the lock operation lever 45 is operated in this way, the lock operation lever 45 can be reliably operated without any malfunction or operation failure depending on the work environment. Further, since the structure is simple, it can be easily and inexpensively added to the existing ATT pilot valve 28.

  Further, in the lever locking mechanism 46, the operation member 44 is pressed against the support plate 42 by the urging coil spring 46b, and the protrusion of the locking sphere 46a is engaged with the locking recess 46c, whereby the lock operating lever 45 is moved. The locking sphere 46a can be easily detached from the locking recess 46c by being able to be locked at the release position O and the locking position R and by slightly tilting the lock operation lever 45 in the axial direction of the support shaft 43. The lock operation lever 45 can be returned from the lock position R to the release position O.

  In the above-described embodiment, the work drive device is the ATT drive motor 8b. However, a work cylinder that drives the attachment device may be used. Moreover, although the ATT lock device 31 which is a work operation lock device is provided in the ATT pilot valve 28, it is not limited to this.

BRIEF DESCRIPTION OF THE DRAWINGS Embodiment of the operation device for work of the working vehicle which concerns on this invention is shown, (a) is a side view which shows an ATT locking device, (b) is a rear view which shows an ATT locking device. The lock passive part of an ATT locking device is shown, (a) is a block diagram of an ATT pilot valve, (b) is a block diagram of an ATT pilot valve when the ATT operation pedal is depressed, and (c) is a step when the ATT operation pedal is depressed. It is a side view of the lock passive part at the time. The lock operation part of an ATT lock apparatus is shown, (a) is sectional drawing of the back view of a lock operation part, (b) is an enlarged side view of a lock operation part. It is a block diagram explaining the hydraulic piping of a work vehicle. It is a side view of a work vehicle.

Explanation of symbols

R Lock position O Release position 1 Car body 3 Work device 4 Work boom 5 Boom cylinder 6 Attachment 7 Bucket cylinder 8 Rotating brush device 8b ATT drive motor 8c Rotating brush 20 Work drive device 21 Main pump 22 Sub pump (hydraulic pump)
23 Work controller 24 Boom control valve 25 Bucket control valve 26 ATT control valve (work control valve)
26a, 26b Pilot part 27 ATT operation pedal 28 ATT pilot valve (working pilot valve)
28F, 28R Spool valve 29 Tilt cam 29a Horizontal shaft 31 ATT lock device (work operation lock device)
31A Lock passive part 31B Lock operation part 31C Lock interlocking member 32 Lock passive lever 33 Wire connector 33a Pin 33b Engagement plate 33c Elongate hole 33d Restraining coil spring 42 Support plate (support member)
43 Support shaft 44 Operation member 44a Operation plate 44b Sleeve 44c Center hole 45 Lock operation lever 46 Lever locking mechanism 46a Locking sphere 46b Biasing coil spring (biasing member)
46c Locking recess 48 Stopper mechanism 49 Lock drive lever 51 Wire cable 51a Wire 51b Cable cover

Claims (2)

A working operation device for a work vehicle that feeds and discharges hydraulic oil discharged from a hydraulic pump to a work drive device via a work control valve and drives the work device,
The work control valve is a pilot hydraulic type,
A work pilot valve for supplying and discharging pilot hydraulic oil to the work control valve is provided, and a work operation pedal for operating the work pilot valve is provided.
Operate the work pilot valve and provide a work operation lock device that can lock the work pilot valve with the operation limit of the work operation pedal.
An operation member that is rotated between a release position and a lock position around a spindle axis by a lock operation lever, and a lever locking mechanism that locks the operation member at the release position and the lock position. A work operation device for a work vehicle, comprising: a lock operation portion having a lock passive portion for operating the work pilot valve; and a lock interlocking member for interlockingly connecting the lock operation portion and the lock passive portion. The lever locking mechanism includes a support member fixed to the vehicle body and facing the operating member, a locking sphere partially projecting at a predetermined position on one facing portion of the support member and the operating member, and the other A locking recess provided at a predetermined position of the facing portion to engage the protruding portion of the locking sphere at the release position and the locking position to lock the operation member, and an urging force to press the operation member against the support member side The work operation device for a work vehicle according to claim 1, wherein a member is provided.

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