JP4585373B2 - Work vehicle travel transmission device - Google Patents

Description

  The present invention relates to a left steering clutch for turning on and off a transmission for a left traveling device, and a traveling transmission device for a work vehicle including a right steering clutch for turning on and off a transmission for a right traveling device.

Conventionally, for example, Patent Document 1 discloses a traveling power transmission device described above.
That is, in what is shown in Patent Document 1, a movable member 80 is provided on both sides of the relay gear 70 in a state of being rotatably and slidably supported by a support shaft 69, and one movable member 80 is provided. As a result of the shifting operation, the meshing transmission portion 81 of the movable member 80 is engaged with and disengaged from the internally fitted transmission portion 82 of the relay gear 70, so that the transmission from the relay gear 70 to the crawler type traveling device 1 on the left side is turned on. The left steering clutch is configured to switch to the cut state, the other movable member 80 is shifted, and the meshing transmission portion 81 of this movable member 80 is engaged with the internal fitting transmission portion 82 of the relay gear 70. The right steering clutch is configured so that the transmission from the relay gear 70 to the crawler type traveling device 1 on the right side is switched between the on state and the off state by being detached.

Japanese Patent Laying-Open No. 2003-136998 (paragraph [0055], FIGS. 7, 9, 10, and 11)

  In the conventional traveling transmission device, it is necessary to separately provide a movable member for constituting and turning on and off the left steering clutch and a movable member for constituting and turning on and off of the right steering clutch. It was complicated in terms. In addition, in order to enable the switching operation by the steering clutch actuator, an actuator for the left steering clutch and an actuator for the right steering clutch are required, which is disadvantageous in terms of structure and size. It was.

  An object of the present invention is to provide a traveling transmission device for a work vehicle that can advantageously obtain a left steering clutch and a right steering clutch in terms of structure and size, and can operate an actuator.

In the present invention , in the travel transmission device of the work vehicle provided with a left steering clutch that turns on and off the transmission to the left traveling device, and a right steering clutch that operates on and off the transmission to the right traveling device,
A left transmission gear linked to the left traveling device and a right transmission gear linked to the right traveling device are arranged in the axial direction of one drive shaft and are fitted on the drive shaft so as to be relatively rotatable. ,
A shift gear externally fitted to the drive shaft so as to be integrally rotatable and slidable between the left transmission gear and the right transmission gear. One end side of the shift gear is an input portion of the left transmission gear, and the other end side is an input portion of the right transmission gear. , The linear drive position where the drive shaft is connected to the left transmission gear and the right transmission gear so as to be integrally rotatable, one end side of the shift gear is engaged with the input portion of the left transmission gear, and the other end side is the right transmission Separated from the gear input section, the drive shaft is connected to the left transmission gear so as to rotate together, and the right turning position is separated from the right transmission gear so as to be rotatable relative to the right transmission gear. Detach from the gear input part, the other end engages with the input part of the right transmission gear, separates the drive shaft relative to the left transmission gear, and connects to the right transmission gear so that it can rotate integrally. The left turn position is provided so that it can be shifted.
An engaged state in which the left transmission gear and the right transmission gear are connected so as to be integrally rotatable in a state where the shift gear is located at the left turning position and the right turning position, and the left transmission gear and the right transmission. Provide a clutch that can be switched to a cut-off state where the gears rotate relative to each other,
The left steering clutch is constituted by the left transmission gear and the shift gear; the right steering clutch is constituted by the right transmission gear and the shift gear ;
A left turning action state in which the driving force of the drive shaft is decelerated and transmitted to the left traveling device so that the left traveling device is driven at a lower speed than the case where the left traveling gear is transmitted from the left transmission gear; A right turning action state in which the driving force of the drive shaft is decelerated and transmitted to the right traveling device so that the traveling device is driven at a lower speed than when the traveling device is transmitted from the right transmission gear; Provided with a decelerating transmission mechanism that can be switched to an action-released state where transmission is cut off,
The speed reduction transmission mechanism includes a rotation transmission shaft on which the drive shaft is fitted so as to be relatively rotatable. The speed reduction clutch switches the speed reduction transmission mechanism between the left turning action state, the right turning action state, and the action releasing state. A mechanism is provided on the rotary transmission shaft.

In other words, when the shift gear is operated to the straight traveling position or the right turning position, the drive shaft and the left transmission gear are connected by the shift gear, and the transmission to the left traveling device is turned on, and when the shift gear is operated to the left turning position, the drive shaft And the connection of the left transmission gear is released and the transmission to the left traveling device is cut off. When the shift gear is operated to the straight drive position or the left turning position, the drive shaft and the right transmission gear are connected by the shift gear, and the transmission to the right traveling device is turned on. When the shift gear is operated to the right turning position, the drive shaft and the right turning gear are turned on. The connection of the transmission gear is released and the transmission to the right traveling device is cut off.
When the shift gear is switched from the left turn position to the straight drive position, the shift gear is switched from the disengaged state to the right drive gear to the engaged state, and when the shift gear is switched from the right turn position to the straight drive position, the shift gear is moved to the left drive gear. Switch from the disengaged state to the engaged state. In these cases, if the shift gear is switched from the right turn position or the left turn position to the straight drive position and the clutch is operated to be engaged, the left transmission gear and the right transmission gear rotate together. In this state, the shift gear can be smoothly switched from the disengaged state with respect to the left transmission gear or the right transmission gear to the meshed state.
As a result, one shift gear constitutes a left steering clutch as well as a movable member that engages and disengages the left steering clutch, and constitutes a right steering clutch and also a movable member that engages and disengages the right steering clutch. Thus, a left steering clutch and a right steering clutch can be obtained.

Therefore, it is possible to obtain a shift gear of a movable member of the left steering clutch, by a simple structure in which combined the shift gear as the movable member of the right steering clutch the left steering clutch and right steering clutch, also, Both steering clutches can be operated by the actuator only by interlocking the actuator with one shift gear, and can be obtained at a low cost and in a compact manner.

Further, when the shift gear is switched to the left turning position and the deceleration transmission mechanism is switched to the left turning action state, the left traveling device is transmitted by the reduction transmission mechanism and driven from the left transmission gear. It is driven at a lower speed than the case where the traveling machine body turns left with a relatively large turning radius. When the shift gear is switched to the right turning position and the speed reduction transmission mechanism is changed to the right turning action state, the right traveling device is transmitted by the speed reduction transmission mechanism, and is transmitted from the right transmission gear and driven. It is driven at a lower speed than the case where the traveling machine body turns right with a relatively large turning radius.

The speed reduction transmission mechanism can be obtained with a compact structure in which the drive shaft and the speed reduction clutch mechanism are supported by the rotation transmission shaft .

Small Therefore, despite those which can be slowly turning with a relatively large turning radius by driving the traveling apparatus swivel inside at a lower speed than the traveling device of the turning outer, the speed reduction transmission mechanism becomes compact Can be obtained.

Embodiments of the present invention will be described below with reference to the drawings.
As shown in FIG. 1, a mowing pre-processing unit 4 is provided at the front of a body frame 3 of a self-propelled aircraft including a pair of left and right crawler type traveling devices 1 a and 1 b and a driving unit equipped with a driver seat 2. While connecting the base part of the pre-processing part frame 4a so that rotation is possible, the raising / lowering cylinder 5 is made to interlock | cooperate with the pre-processing part frame 4a, and the threshing apparatus 6 and the grain tank 7 are provided in the rear side of the said body frame 3, Combine is configured.

  This combine harvests rice, wheat, and the like. When the lifting cylinder 5 is expanded and contracted, the lifting cylinder 5 swings the pretreatment unit frame 4a up and down with respect to the body frame 3 to cut and harvest. The pre-processing unit 4 is raised and moved up and down to a lowering work state in which the raising start end of the device 4b is located near the ground and a raising non-working state in which the raising device 4b and the like are lifted from the ground. When the pre-cutting processing unit 4 is in the descending work state and the self-propelled machine is traveling, the pre-cutting processing unit 4 causes the plurality of pulling devices 4b arranged in the horizontal direction of the machine to raise and process the planted culm, The planting cereal stock that is raised and processed by the pulling device 4b is cut by the clipper-type cutting device 4c, and the cutting mash from the cutting device 4c is conveyed backward by the conveying device 4d. The threshing device 6 is supplied to the start end of the threshing feed chain 6a. The threshing device 6 supplies the tip side to a handling room (not shown) while squeezing and conveying the stock side of the harvested cereal meal by the threshing feed chain 6a, and performs the threshing process. The grain tank 7 collects and stores the threshing grains from the threshing device 6.

  An engine 8 is provided below the driver seat 2 of the traveling machine body, and a traveling transmission device that transmits the driving force of the engine 8 to the left and right traveling devices 1a and 1b is configured as shown in FIG.

  That is, the output from the output shaft 8a of the engine 8 is transmitted to the input shaft 12a of the hydrostatic continuously variable transmission 12 that also serves as the input shaft of the transmission case 11 via the transmission mechanism using the transmission belt 10. The output from the output shaft 12b of the hydraulic continuously variable transmission 12 is transmitted to the shift gear 14 of the travel subtransmission 13, and the output from the cylindrical shaft output shaft 15 of the travel subtransmission 13 is left-handed. It is transmitted to the crawler drive shaft 9a of the left traveling device 1a via the clutch 20a and the gear transmission mechanism 30a, and the output from the output shaft 15 of the traveling auxiliary transmission 13 is the right steering clutch 20b and the gear transmission mechanism 30b. The speed reduction transmission mechanism 40 is configured to be transmitted to the crawler drive shaft 9b of the right side travel device 1b via the motor and linked to the output shaft 15 of the travel auxiliary transmission device 13, and this speed reduction transmission Straight return clutch provided in the structure 40 50, it is then configured with a steering brake 55 annexed to the output shaft 15 to the rotation transmission shaft 16 to rotatably supported in the traveling auxiliary transmission 13.

As clearly shown in FIG. 3, the traveling sub-transmission 13 includes the shift gear that is also used as an input member that is supported by the output shaft 12 b of the hydrostatic continuously variable transmission 12 so as to be integrally rotated and slidable by spline engagement. 14, a pair of transmission gears 17a, 17b with which the pair of transmission gears 14a, 14b of the shift gear 14 are individually engaged and disengaged, and the output shaft 15 provided with the pair of transmission gears 17a, 17b so as to be integrally rotatable. It is.
That is, in the traveling auxiliary transmission 13, the hydrostatic continuously variable transmission 12 is engaged with the transmission gear 14a by being engaged with the transmission gear 17a and the transmission gear 14b by being engaged with the transmission gear 17b. The driving force of the output shaft 12b is transmitted to one end side of the output shaft 15 via the transmission gear 14a and the transmission gear 17a and output from the intermediate portion of the output shaft 15 to the left steering clutch 20a and the right steering clutch 20b. Or the transmission force of the output shaft 12b of the hydrostatic continuously variable transmission 12 is transmitted to the other end of the output shaft 15 via the transmission gear 14b and the transmission gear 17b. In this way, a shift state of high-speed transmission is set so as to output to the left steering clutch 20a and the right steering clutch 20b from the intermediate portion.

  As shown in FIG. 3, the left steering clutch 20a is rotated relative to one end side of the output shaft 15 as a drive shaft in a state of being linked to the crawler drive shaft 9a of the left traveling device 1a by the gear transmission mechanism 30a. The left transmission gear 21a that is freely fitted and the left transmission gear 21a and the right transmission gear 21b that is fitted to the other end of the output shaft 15 are integrally rotated with the support portion 15a of the output shaft 15. And a shift gear 22 slidably fitted outside. The right steering clutch 20a includes a right transmission gear 21b that is externally fitted to the output shaft 15 so as to be rotatable relative to the crawler drive shaft 9a of the right traveling device 1b by the gear transmission mechanism 30a. A shift gear 22 is provided.

  Input portions 23a and 23b having gears provided on the outer peripheral surface side are provided on the mounting cylinder portions of the left transmission gear 21a and the right transmission gear 21b, and the shift gear 22 is slid along the support portion 15a. Thus, as shown in FIG. 3, one end side of the shift gear 22 is engaged with the gear of the input portion 23a located in the attachment cylinder portion of the left transmission gear 21a, and the other end side of the shift gear 22 is engaged with the attachment cylinder portion of the right transmission gear 21b. A straight drive position N that engages with the gear of the input portion 23b and is connected to the left transmission gear 21a and the right transmission gear 21b so as to be integrally rotatable, and the shift gear 22 as shown in FIG. One end side engages with the gear of the input part 23a of the left transmission gear 21a, the other end side of the shift gear 22 disengages from the input part 23b of the right transmission gear 21b, and the output shaft 15 is connected to the left transmission gear 21a. On the other hand, the right turning position R is connected so as to be integrally rotatable and separated relative to the right transmission gear 21b, and one end side of the shift gear 22 is the input portion 23a of the left transmission gear 21a as shown in FIG. And the other end side of the shift gear 22 engages with the gear of the input portion 23b of the right transmission gear 21b to separate the drive shaft 15 relative to the left transmission gear 21a so as to be rotatable relative to the right transmission gear 21b. Thus, it is configured to switch to the left turning position L that is connected so as to be integrally rotatable.

  Thus, when the shift gear 22 is operated to the straight traveling position N and the right turning position R, the left steering clutch 20a applies the driving force from the output shaft 15 of the traveling auxiliary transmission 13 to the left transmission gear via the shift gear 22. When the shift gear 22 is operated to the left turning position L when the shift gear 22 is operated to the left turning position L, the travel subtransmission 13 is transmitted to the left travel gear 21a from the left transmission gear 21a via the gear transmission mechanism 30a. The transmission from the output shaft 15 to the left transmission gear 21a is cut off, and the transmission to the left traveling device 1a is cut off. The right steering clutch 20b transmits the driving force from the output shaft 15 of the traveling auxiliary transmission 13 to the right transmission gear 21b via the shift gear 22 when the shift gear 22 is operated to the straight traveling position N and the left turning position L. When the shift gear 22 is operated to the right turning position R when the right transmission gear 21b is transmitted to the right traveling device 1b via the gear transmission mechanism 30b, the output shaft of the traveling auxiliary transmission 13 is set. 15, the transmission to the right transmission gear 23b is cut off, and the transmission to the right traveling device 1b is cut off.

  As shown in FIG. 3, the speed reduction transmission mechanism 40 is mounted on the rotary transmission shaft 16 that supports the output shaft 15 of the traveling auxiliary transmission 13 so as to be relatively rotatable, and on one end side of the rotary transmission shaft 16. A pair of fitted transmission gears 41a, 41b, a left reduction gear 42a meshed with a left transmission gear 41a of the pair of transmission gears 41a, 41b, and a left reduction gear 42a are supported on one end side so as to be integrally rotatable. The pair of transmission gears, the rotation transmission shaft 43, which supports the intermediate gear 31a of the gear transmission mechanism 30a on the end side so as to be integrally rotatable and interlocks the left reduction gear 42a with the gear transmission mechanism 30a of the left traveling device 1a. 41a, 41b, the right reduction gear 42b meshed with the right transmission gear 41b, the right reduction gear 42b is integrally formed on one end side, and the gear transmission mechanism 30b on the other end side. Intermediate gear 31b is have configured provided with a like rotation transmission shaft 44 of the tubular which links the right deceleration gear 42b to the gear transmission mechanism 30b of the right traveling device 1b be integrally molded.

  The multi-plate friction type reduction clutch 46 provided between the transmission gear 17b of the output shaft 15 of the traveling auxiliary transmission 13 and the rotation transmission shaft 16, and the left transmission gear 41a and the right The reduction transmission mechanism 40 includes a reduction clutch mechanism 48 that includes a reduction shift gear 47 that is supported by the support portion 16a of the rotary transmission shaft 16 so as to be integrally rotatable and slidable between the transmission gear 41b.

  The deceleration clutch 46 is switched between an on state and a disengaged state by a hydraulic piston 46 a located in the clutch body of the reduction clutch 46. The reduction clutch 46 is switched to the engaged state, and the reduction shift gear 47 is engaged with the input gear portion of the left transmission gear 41a and the support portion 16a of the rotary transmission shaft 16 so as to be integrally rotatable, and the input of the right transmission gear 41b. When the gear is separated from the gear portion and is shifted to the left traveling transmission position in which only the left transmission gear 41a of the left transmission gear 41a and the right transmission gear 41b is connected to the rotary transmission shaft 16 so as to be integrally rotatable, the speed is reduced. The clutch mechanism 48 enters the left turning state and switches the deceleration transmission mechanism 40 to the left turning action state. The reduction clutch 46 is switched to the engaged state, and the reduction shift gear 47 is engaged with the input gear portion of the right transmission gear 41b and the support portion 16a of the rotary transmission shaft 16 so as to be integrally rotatable, and the input of the left transmission gear 41a. When separated from the gear portion and shifted to the right traveling transmission position in which only the right transmission gear 41b of the left transmission gear 41a and the right transmission gear 41b is connected to the rotary transmission shaft 16 so as to be integrally rotatable, The speed reduction clutch mechanism 48 enters the right turning state and switches the speed reduction transmission mechanism 40 to the right turning action state. When the speed reduction clutch 46 is switched to the disengaged state, the speed reduction clutch mechanism 48 is configured to switch the speed reduction transmission mechanism 40 to the action release state.

The speed reduction transmission mechanism 40 that has been switched to the left-turning action state transmits the driving force of the output shaft 15 of the traveling subtransmission mechanism 13 to the left transmission gear 41 a via the speed reduction clutch 46, the rotation power transmission shaft 16, and the speed reduction shift gear 47. The left transmission gear 41a and the left reduction gear 42a are decelerated and transmitted from the left reduction gear 42a to the gear transmission mechanism 30a via the rotation transmission shaft 43, thereby reducing the driving force of the output shaft 15 and driving on the left side. This is transmitted to the crawler drive shaft 9a of the device 1a, and the left traveling device 1a is driven at a lower speed than the case where it is transmitted from the left transmission gear 21a.
The reduction transmission mechanism 40 that has been switched to the right-turning action state transfers the driving force of the output shaft 15 of the traveling subtransmission mechanism 13 to the right transmission gear 41b via the reduction clutch 46, the rotation transmission shaft 16, and the reduction shift gear 47. The transmission force is reduced by the right transmission gear 41b and the right reduction gear 42b and transmitted from the right reduction gear 42b to the gear transmission mechanism 30b via the rotation transmission shaft 44, thereby reducing the driving force of the output shaft 15. Then, it is transmitted to the crawler drive shaft 9b of the right traveling device 1b, and the right traveling device 1b is driven at a lower speed than the case where it is transmitted from the right transmission gear 21b.
The speed reduction transmission mechanism 40 that has been switched to the action release state cuts off the transmission to the left and right traveling devices 1a and 1b by cutting off the transmission from the output shaft 15 of the traveling subtransmission mechanism 13 to the rotating transmission shaft 16.

  The rectilinear return clutch 50 is configured to be switched between an on state and a disconnected state by a hydraulic piston 50 a between the right reduction gear 42 b of the reduction transmission mechanism 40 and the rotation transmission shaft 43. The straight-return return clutch 50 that has been switched to the engaged state causes the right reduction gear 42b and the rotary transmission shaft 43 to frictionally interlock with each other so as to be integrally rotatable, and the transmission gear 31b in the gear transmission mechanism 30b and the transmission gear 31a in the gear transmission mechanism 30a. , So that the left transmission gear can be operated even when the shift gear 22 is in the left turning position L or the shift gear 22 is in the right turning position R. The transmission gear 21a and the right transmission gear 21b are connected to both the transmission gears 21a and 21b so as to be integrally rotatable. The rectilinear return clutch 50 that has been switched to the disconnected state releases the connection between the transmission gears 21a and 21b so that the left transmission gear 21a and the right transmission gear 21b rotate relative to each other.

The steering brake 55 includes a rotating body 56 coupled to the rotary transmission shaft 16 so as to be integrally rotatable, and a multi-plate friction brake mechanism provided between the outer peripheral side of the rotating body 56 and the support portion 11 a of the transmission case 11. 57, and the operation arm 58 supported by the mission case 11 via the rotary operation shaft 58a is operated to swing, whereby the friction brake mechanism 57 is moved to the receiving portion 11b of the mission case 11 by the pressure plate 59. It enters a press-contacted state or a cut-off state in which the pressure plate 59 is disengaged from the pressure-contacting portion 11b of the friction brake mechanism 57.
The steering brake 55 in the engaged state applies friction braking to the rotation transmission shaft 16 via the rotating body 56 by the friction brake mechanism 57, and the reduction transmission gear 47, the left transmission gear 41a, and the left reduction gear are transmitted from the rotation transmission shaft 16. By applying friction braking to the crawler drive shaft 9a via the gear 42a, the rotation transmission shaft 43, and the gear transmission mechanism 30a, a friction brake is applied to the left traveling device 1a, or the speed reduction gear 47 from the rotation transmission shaft 16 to the right By applying friction braking to the crawler drive shaft 9b through the transmission gear 41b, the right reduction gear 42b, the rotation transmission shaft 44, and the gear transmission mechanism 30b, a friction brake is applied to the right traveling device 1b.
The steering brake 55 that has been turned off releases the friction brake applied to the left traveling device 1a and the right traveling device 1b by releasing the friction braking of the rotation transmission shaft 16 by the friction brake mechanism 57.

One steering actuator 60 linked to a shifter (not shown) for slidingly operating the shift gear 22 of the left steering clutch 20a and the right steering clutch 20b is provided outside the transmission case 11, and this steering actuator is provided. The shift gear 22 is slid and operated by swinging the shifter 60. One reduction actuator 61 linked to a shifter (not shown) for slidingly operating the reduction shift gear 47 of the reduction clutch mechanism 40 is provided outside the transmission case 11, and the shifter is swung by the reduction actuator 61 . By doing so, the reduction shift gear 47 is configured to slide. A speed reduction clutch valve 67 connected to a hydraulic piston 46 a for operating the speed reduction clutch 46 of the speed reduction clutch mechanism 48 via an operation oil passage (not shown) located inside the rotation transmission shaft 16 is provided in the transmission case 11. Provided outside, the speed reduction clutch 46 is switched by operating the hydraulic piston 46 a by the speed reduction clutch valve 67. A rectilinear return valve 63 connected to a hydraulic piston 50a for switching the rectilinear return clutch 50 via an operating oil passage (not shown) located inside the rotation transmission shaft 43 is provided outside the mission case 11. The rectilinear return clutch 50 is switched by operating the hydraulic piston 46a by the rectilinear return valve 63. A brake actuator 64 is interlocked with the operation arm 58 of the steering brake 55, and the steering brake 55 is switched by swinging the operation arm 58 with the brake actuator 64.

  As shown in FIG. 5, a control means 66 is linked to the steering actuator 60, the deceleration actuator 61, the deceleration clutch valve 67, the rectilinear return valve 63, and the brake actuator 64. A steering sensor 68 linked to the steering lever 67 is linked.

  The steering lever 67 is provided in front of the driver's seat 2 of the driving unit and travels straight, the left first turning position L1 swinging to the left side of the aircraft from the straight traveling position S, and the left first turning position. Left second turning position L2 swinging to the left side of the aircraft from L1, left third turning position L3 swinging from the left second turning position L2 to the left side of the aircraft, right side of the aircraft from the straight advance position S Right first turning position R1 swung to the right side, right second turning position R2 swung to the right side of the body from the right first turning position R1, and to the right side of the body from the second right turning position R2. A swing operation is performed in the lateral direction of the airframe to each operation position of the swing right third turning position R3.

  The steering sensor 68 is composed of a rotary operation potentiometer linked to the steering lever 67 so as to detect the operation position of the steering lever 67, and outputs the detection result to the control means 66 as an electric signal.

The control means 66 is configured by using a microcomputer, and operates the steering actuator 60 by operating the steering actuator 60 based on the information detected by the steering sensor 68 and a program inputted in advance, and the rectilinear return valve 63. Is operated by operating the straight-return return clutch 50, by operating the deceleration actuator 61, the deceleration shift gear 47 is operated, the deceleration clutch valve 67 is operated by operating the deceleration clutch valve 67, and the steering actuator 55 is operated by operating the brake actuator 64. Are operated in a state corresponding to the operation position of the steering lever 67.

  That is, by swinging the steering lever 67 in the lateral direction of the machine body, the control means 66 operates the left steering clutch 20a, the right steering clutch 20b, the speed reduction transmission mechanism 40, and the steering brake 55 to control the traveling machine body. The steering operation can be performed.

  That is, when the steering lever 67 is swung in the lateral direction of the airframe and operated to the straight position S, the control means 66 switches the shift gear 22 to the straight position N based on the information detected by the steering sensor 68 and moves the left. The steering clutch 20a and the right steering clutch 20b are switched to the engaged state, and at the same time, the control means 66 operates the deceleration clutch 46 to the disengaged state so that the deceleration transmission mechanism 40 is applied to both the left and right traveling devices 1a and 1b. The operation is switched to the operation release state so as not to be transmitted, the left traveling device 1a is driven by the transmission by the gear transmission mechanism 30a, the right traveling device 1b is driven by the transmission by the gear transmission mechanism 30b, and the left and right traveling devices 1a. , 1b drive speed becomes the same, and the traveling machine body travels straight.

  When the steering lever 67 is switched from the left first, second, third turning positions L1, L2, L3 to the straight traveling position S, the shift gear 22 is switched from the left turning position L to the straight traveling position N, and the steering lever 67 is moved. When the right first, second, third turning positions R1, R2, R3 are switched from the straight turning position S to the straight running position S, the shift gear 22 is switched from the right turning position R to the straight running position N. In these cases, the control means 66 switches the rectilinear return clutch 50 to the engaged state based on the detection information from the steering sensor 68, and the rectilinear return clutch 50 causes the rotation transmission shaft 43 of the deceleration transmission mechanism 40 and the The left transmission gear 21a of the left steering clutch 20a and the right transmission gear 21b of the right steering clutch 20b are integrally rotated by connecting the reduction gear 42b so as to be integrally rotatable, and the shift gear 22 and the left transmission to which the shift gear 22 should mesh While the gears 21a and the input parts 23a and 23b of the right transmission gear 21b are synchronized so that the shift gear 22 meshes smoothly with the input parts 23 and 23b of the left transmission gear 21a and the right transmission gear 21b, the shift gear 22 is moved to the left turning position. Switching operation from L or right turn position R to straight drive position N is performed.

  When the steering lever 67 is operated to the left first turning position L1, the control means 66 switches the shift gear 22 to the left turning position L based on the information detected by the steering sensor 68, and the left steering clutch 20a is disengaged. Next, the right steering clutch 20b is switched to the engaged state, the control means 66 is switched to the engaged state of the deceleration clutch 46, and the deceleration shift gear 47 is switched to the left travel transmission position to move the deceleration transmission mechanism 40 to the left side. The left turning device 1a is switched to the left turning action state so as to be transmitted to the traveling device 1a, and the control means 66 is further operated to switch the steering brake 55 to the off state. It is driven at a lower speed than the traveling device 1b, and the right traveling device 1b is transmitted by the gear transmission mechanism 30b than the left traveling device 1a. The drive has been traveling machine body is left at a speed, the left and right traveling devices 1a, for turning with a relatively large turning radius which is determined by the driving speed difference 1b.

  When the steering lever 67 is operated to the left second turning position L2, the control means 66 switches the shift gear 22 to the left turning position L based on the information detected by the steering sensor 68, and the left steering clutch 20a is disengaged. In addition, the right steering clutch 20b is switched to the engaged state, and the control means 66 is operated to disconnect the deceleration clutch 46 so that the deceleration transmission mechanism 40 is not transmitted to any of the left and right traveling apparatuses 1a and 1b. In addition, the control means 66 switches the steering brake 55 to the off state, the left traveling device 1a enters the idle state and the right traveling device 1b is driven by the gear transmission mechanism 30b. Driven by transmission, the traveling machine body turns left and turns with a smaller turning radius than when the steering lever 67 is operated to the left first turning position L1.

  When the steering lever 67 is operated to the left third turning position L3, the control means 66 switches the shift gear 22 to the left turning position L based on the information detected by the steering sensor 68, and the left steering clutch 20a is disengaged. In addition, the right steering clutch 20b is operated in the engaged state, and the control means 66 is operated in the disengaged state of the deceleration clutch 46 so that the deceleration transmission mechanism 40 is not transmitted to any of the left and right traveling devices 1a and 1b. The operation is switched to the action release state, the deceleration shift gear 47 is switched to the left traveling transmission position so that the braking by the steering brake 55 reaches the left traveling device 1a, and the control means 66 is turned on. To the left traveling device 1a, the friction brake is applied by the steering brake 55, and the right traveling device 1b is transmitted by the gear transmission mechanism 30b. Driven by traveling machine body is to the left, the left traveling device 1a is turning so as to be turning center by.

  When the steering lever 67 is operated to the first right turning position R1, the control means 66 switches the shift gear 22 to the right turning position R based on the information detected by the steering sensor 68 and enters the left steering clutch 20a. In this state, the right steering clutch 20b is switched to the disengaged state, the control means 66 is switched to the engaged state of the deceleration clutch 46, and the deceleration shift gear 47 is switched to the right travel transmission position to operate the deceleration transmission mechanism 40. The right traveling device 1a is switched to the right turning operation state so as to be transmitted to the right traveling device 1a, and the control means 66 is further operated to switch the steering brake 55 to the disconnected state, and the left traveling device 1a is transmitted by the transmission by the gear transmission mechanism 30a. The right traveling device 1b is driven at a higher speed than the right traveling device 1b, and the right traveling device 1b is transmitted by the speed reduction transmission mechanism 40 to the left traveling device 1a. The drive has been traveling machine body is right at a speed, the left and right traveling devices 1a, for turning with a relatively large turning radius which is determined by the driving speed difference 1b.

  When the steering lever 67 is operated to the right second turning position R2, the control means 66 switches the shift gear 22 to the right turning position R based on information detected by the steering sensor 68 and enters the left steering clutch 20a. In this state, the right steering clutch 20b is switched to the disengaged state, and the control means 66 operates the deceleration clutch 46 to the disengaged state so that the speed reduction transmission mechanism 40 is not transmitted to any of the left and right traveling devices 1a and 1b. Then, the control means 66 switches the steering brake 55 to the disengaged state so that the left traveling device 1a is driven by transmission by the gear transmission mechanism 30a and the right traveling device 1b. Turns into a free-wheeling state, the traveling body turns rightward, and turns with a turning radius smaller than when the steering lever 67 is operated to the right first turning position R1.

When the steering lever 67 is operated to the right third turning position R3, the control means 66 switches the shift gear 22 to the right turning position R based on information detected by the steering sensor 68 and enters the left steering clutch 20a. In this state, the right steering clutch 20b is operated in the disengaged state, and the control unit 66 operates the deceleration clutch 46 in the disengaged state so that the speed reduction transmission mechanism 40 is not transmitted to any of the left and right traveling devices 1a and 1b. Is switched to the right travel transmission position so that the braking by the steering brake 55 reaches the right traveling device 1b, and the control means 66 enters the steering brake 55. The left traveling device 1a is driven by the transmission of the gear transmission mechanism 30a, and the right traveling device 1b is driven by the steering brake 55. Takes brake, the traveling machine body is to the right, the right traveling device 1b is turning so as to be turning center.
[Another Example]
The present invention can be applied not only to a combine harvester but also to a harvester that uses various crops such as carrots and onions as harvesting targets. Therefore, these combines, harvesters, etc. are collectively referred to as work vehicles.

Side view of the entire combine Travel transmission device diagram Sectional view at the location of the steering clutch and deceleration transmission mechanism of the traveling transmission device (A) is an explanatory view of the right turning position R of the shift gear, (b) is an explanatory view of the left turning position L of the shift gear, Block diagram of the aircraft steering operation device

Explanation of symbols

1a Left traveling device 1b Right traveling device 15 Drive shaft 16 Rotation transmission shaft 20a Left steering clutch 20b Right steering clutch 21a Left transmission gear 21b Right transmission gear 22 Shift gear 23a Left transmission gear input portion 23b Right transmission gear input Portion 40 Reduction gear transmission mechanism 48 Reduction clutch mechanism 50 Clutch N Shift gear rectilinear position L Shift gear left turn position R Shift gear right turn position

Claims (1)

A left steering clutch for turning on and off the transmission for the left side traveling device, and a right transmission clutch for a working vehicle having a right steering clutch for turning on and off the transmission for the right side traveling device,
A left transmission gear linked to the left traveling device and a right transmission gear linked to the right traveling device are arranged in the axial direction of one drive shaft and are fitted on the drive shaft so as to be relatively rotatable. ,
A shift gear externally fitted to the drive shaft so as to be integrally rotatable and slidable between the left transmission gear and the right transmission gear. One end side of the shift gear is an input portion of the left transmission gear, and the other end side is an input portion of the right transmission gear. , The linear drive position where the drive shaft is connected to the left transmission gear and the right transmission gear so as to be integrally rotatable, one end side of the shift gear is engaged with the input portion of the left transmission gear, and the other end side is the right transmission Separated from the gear input section, the drive shaft is connected to the left transmission gear so as to rotate together, and the right turning position is separated from the right transmission gear so as to be rotatable relative to the right transmission gear. Detach from the gear input part, the other end engages with the input part of the right transmission gear, separates the drive shaft relative to the left transmission gear, and connects to the right transmission gear so that it can rotate integrally. The left turn position is provided so that it can be shifted.
An engaged state in which the left transmission gear and the right transmission gear are connected so as to be integrally rotatable in a state where the shift gear is located at the left turning position and the right turning position, and the left transmission gear and the right transmission. Provide a clutch that can be switched to a cut-off state where the gears rotate relative to each other,
The left steering clutch is constituted by the left transmission gear and the shift gear; the right steering clutch is constituted by the right transmission gear and the shift gear ;
A left turning action state in which the driving force of the drive shaft is decelerated and transmitted to the left traveling device so that the left traveling device is driven at a lower speed than the case where the left traveling gear is transmitted from the left transmission gear; A right turning action state in which the driving force of the drive shaft is decelerated and transmitted to the right traveling device so that the traveling device is driven at a lower speed than when the traveling device is transmitted from the right transmission gear; Provided with a decelerating transmission mechanism that can be switched to an action-released state where transmission is cut off,
The speed reduction transmission mechanism includes a rotation transmission shaft on which the drive shaft is fitted so as to be relatively rotatable. The speed reduction clutch switches the speed reduction transmission mechanism between the left turning action state, the right turning action state, and the action releasing state. A traveling transmission device for a work vehicle , wherein a mechanism is provided on the rotary transmission shaft .

Images