JP3502025B2 - Traveling gear for work vehicles - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an on-state for straight traveling in which a left traveling drive gear for driving a left traveling device is interlocked with a straight traveling transmission gear, and an on-state for turning in which the left traveling drive gear is interlocked with a left swivel gear. It is equipped with a left steering clutch mechanism that can be freely switched to the right traveling drive gear that drives the right traveling device with the straight transmission gear, and with the right traveling drive gear that rotates with the right rotation gear. It is equipped with a right steering clutch mechanism that can be switched between the state and the state, and the rotation power of the drive shaft is transmitted in reverse by the intermediate transmission shaft to rotate the left turning gear and the right turning gear in the rotation direction opposite to that of the straight transmission gear. The reverse rotation transmission state in which the drive shaft is driven and the rotational force of the drive shaft are decelerated and transmitted to rotate the left turning gear and the right turning gear in the same rotation direction as the straight transmission gear at a lower speed than the straight transmission gear. Turn off the transmission On the work vehicle traveling transmission apparatus that is provided with a place freely pivoting transmission mechanism.

[0002]

2. Description of the Related Art In the above-mentioned work vehicle, a turning transmission mechanism is switched to a low speed transmission state, one of a left steering clutch mechanism and a right steering clutch mechanism is switched to a straight-travel entering state, and the other is switched to a turning entering state. As a result, one of the left and right traveling devices is driven at a lower speed than the other, and the body slowly turns due to the speed difference between the left and right traveling devices. By switching the turning transmission mechanism to the reverse rotation transmission state and switching one of the left steering clutch mechanism and the right steering clutch mechanism to the straight traveling on state and the other to the swiveling on state, one of the left and right traveling devices moves forward. On the other hand, the other is driven to the reverse side, and the body is super-turned by the reverse drive of the left and right traveling devices.

In this type of work vehicle, there is a work vehicle disclosed in, for example, Japanese Patent Application Laid-Open No. 2000-118434. That is, when the transmission gear of the turning transmission mechanism is shifted toward the side wall of the transmission case, the engagement portion of the transmission gear engages with the meshing portion provided on the cover fixed to the transmission case, and the engagement causes transmission. If the turning brake is configured so that the turning gear is braked via the gear and the intermediate transmission shaft, and the turning clutch mechanism is switched to the turning on state with this turning brake on the entry side, this turning clutch mechanism is supported. The brake is applied to the traveling device on the side of the vehicle, and the vehicle pivots on the brake side with the traveling device on the brake side inside. Further, there is a vehicle in which a parking brake is attached to the intermediate transmission shaft so that the parking brake can be applied.

[0004]

In this type of work vehicle, the vehicle is in a straight steering state when parked. That is, both the left steering clutch mechanism and the right steering clutch mechanism are in the on-state for straight travel, and both the left traveling drive gear and the right traveling drive gear are connected to the straight transmission gear. Then, conventionally, when the brake turning is selected, the transmission gear and the drive shaft are disconnected so that the drive gear and the drive shaft rotate relative to each other, so that the parking brake acts on the drive shaft. Since it does not hang on the traveling device without it, when parking, the parking brake acts on the drive shaft from the intermediate transmission shaft through the transmission gear to hang on either the left or right traveling device, so that the vehicle turns gently,
It was necessary to switch the turning transmission mechanism to a state in which one of the super turning and the brake turning other than the brake turning was selected. An object of the present invention is not only to make a brake turn but also to make a running transmission of a work vehicle in which the parking brake is applied to the left and right traveling devices even when any of the slow turn, the super-stable turn, and the brake turn is selected. To provide a device.

[0005]

The constitution, action and effect of the invention according to claim 1 are as follows.

[Structure] The left traveling drive gear that drives the left traveling device can be switched between a straight traveling entry state in which the left traveling drive gear is interlocked with a straight transmission gear and a turning entry state in which the left traveling drive gear is interlocked with the left turning gear. Equipped with a steering clutch mechanism, the right traveling drive gear that drives the right traveling device can be switched between a straight advance state in which the right transmission gear is linked to the straight transmission gear and a right state in which the right drive gear is linked to the right swing gear. With a right steering clutch mechanism,
Driving force for the straight transmission gear and the left and right turning gears
The drive shaft on the lower side in the power transmission direction.
The rotary power of the drive shaft is set to the left turning gear and the right turning gear.
With a pair of left and right intermediate transmission shafts that transmit separately,
Transmission from the drive shaft to the left turning gear and the right turning gear
The reverse rotation transmission state in which the rotational power of the drive shaft is reversely transmitted to the system by the intermediate transmission shaft to rotate the left swing gear and the right swing gear in a rotation direction opposite to that of the straight transmission gear, and the drive shaft of the drive shaft. A turning transmission mechanism that can switch between the left turning gear and the right turning gear by decelerating and transmitting the turning power to a low speed transmission state in which the left turning gear and the right turning gear are rotated in the same rotation direction as the straight transmission gear at a lower speed than the straight transmission gear In a traveling transmission device for a work vehicle provided, the swing transmission mechanism can be switched to a cut state in which the transmission to the left swing gear and the right swing gear is cut off by disconnecting the interlock between the drive shaft and the intermediate transmission shaft. Configured on the left
A swing brake is attached to each of the right intermediate transmission shafts, and a parking brake is attached to the drive shaft.

[Operation] The turning transmission mechanism is set to the disengaged state, the turning brake is set to the entry side, and one of the left steering clutch mechanism and the right steering clutch mechanism is set to the straight entry state.
When the other is switched to the turning on state, one traveling device is driven by this linear transmission gear in conjunction with the linear transmission gear via the steering clutch mechanism, and the other traveling device is operated by the steering clutch mechanism and the turning gear. , The swing brake is applied via the intermediate transmission shaft. As a result, the machine body turns with the traveling device on which the brake is applied turning inside.

Since the parking brake is attached to the drive shaft, when the parking brake is operated to the entrance side, the turning transmission mechanism is switched between the reverse rotation transmission state, the low speed transmission state, and the cut state, and the drive shaft is not connected. Whether the intermediate transmission shaft is in the interlocked state or the interlocked off state, the parking brake acts on the drive shaft, and this braking force causes the linear transmission mechanism,
It is applied to both left and right traveling devices via a straight transmission gear and a steering clutch mechanism.

[Effect] Therefore, a desired turn or an appropriate turn can be selected from a super turning turn, a gentle turn, and a brake turn, and swift turning can be performed, or turning can be performed while the ground is less disturbed. In addition, when parking, whether you have selected a gentle turn, a super turning turn, or a brake turn, you can easily operate the left and right by simply turning on the parking brake without changing the selection. The traveling device can be braked.

The structure, operation, and effect of the invention according to claim 2 are as follows.

[Structure] In the structure of the invention according to claim 1, the swing brake is formed as a separate component from the mission case and is fixed to the fixed case brake body, and the intermediate transmission shaft rotates integrally. And a non-circular movable brake body that is slidably supported and engages with and disengages from the fixed brake body.

[Operation] In the case where the mission case is made of aluminum alloy to reduce the weight, or in the case of a mission case without a swing brake, the mission case is provided with a fixed side brake body formed of a different material and fixed. In view of the strength and shape of the mission case, the traveling device can be firmly braked so that the turning brake can be obtained or provided.

[Effect] Even if the transmission case is lightened or the existing transmission is provided with a turning brake, it is possible to firmly apply the brake by the strong fixed side brake body to turn the brake. By adding a fixed-side brake body that is a separate component from the mission case, it becomes possible to inexpensively turn the brake.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION As shown in FIG. 1, the rotational force of an output shaft 1 of an engine E is transmitted through a main clutch 2 composed of a belt tension clutch to a hydraulic pressure of a hydrostatic continuously variable transmission 3 as a main transmission device. It is configured to be transmitted to the input shaft 3a of the pump. In the transmission case 4 to which the casing of the continuously variable transmission 3 is connected, the rotational power of the output shaft 3b of the hydraulic motor of the continuously variable transmission 3 is input to the shift gear 5 of the auxiliary transmission M. The rotational force of the output shaft 7 is transmitted to the shaft 6 and the rotational force of the output shaft 7 is linearly transmitted by the speed change gear 8 located at the center of the three speed change gears supported integrally rotatably by the output shaft 7 of the auxiliary transmission M. 9 for supporting the rectilinear transmission gear 9 by a swing transmission mechanism 10 including shift gears 11 that are integrally rotatably supported at both ends of the output shaft 7 of the auxiliary transmission M. The rotational power of the output shaft 7 is transmitted to the swivel gears 19a and 19b that are relatively rotatably attached to portions of the rotating shaft 9a located on both sides of the straight transmission gear 9. By selecting the straight traveling transmission gear 9 and one of the pair of swinging gears 19a and 19b, which is the left swinging gear 19a, by the left steering clutch mechanism 20 and connecting to the left traveling drive gear 30a, the straight traveling transmission gear 9 or The turning power of the left turning gear 19a is transmitted to the left traveling drive gear 30a, and the transmission gear 31 is transmitted by the left traveling drive gear 30a.
The left crawler type traveling device 34a is configured to be driven via a, 32a and the crawler drive shaft 33a.
The straight transmission gear 9 and the pair of turning gears 19a, 1
By selecting the other right turning gear 19b of 9b by the right steering clutch mechanism 20 and connecting it to the right running drive gear 30b, the turning power of the straight transmission gear 9 or the right turning gear 19b is changed to the right running drive gear. 30b, and the right traveling drive gear 30b is configured to drive the right crawler type traveling device 34b via the transmission gears 31b and 32b and the crawler drive shaft 33b, thus constituting a combine traveling transmission device. There is.

As shown in FIG. 1 and the like, in the turning transmission mechanism 10, the pair of shift gears 11 and an input gear 13a with which the left shift gear 11 of the pair of shift gears 11 engages and disengages are integrally rotatable on one end side. And an output gear 13b which is engaged with the left turning gear 19a on the other end side so as to be integrally rotatable, and is rotatably supported by the transmission case 4 via bearings 14a and 14b. 13 and the pair of shift gears 1
An input gear 13a for engaging and disengaging the shift gear 11 on the right side of 1 is integrally rotatable at one end side, and an output gear 13b engaged with the right turning gear 19b is integrally rotatable at the other end side at the other end side. And the intermediate transmission shaft 13 rotatably supported by the transmission case 4 via bearings 14a and 14b.

As shown in FIG. 3, etc., the output shaft 7 is
With respect to the three shift gears 8 of the auxiliary transmission M, and with respect to the collar K1 located between the output shaft 7 and the bearing, between the shift gears and between the shift gear and the collar K1. The positioning collar K2 is also engaged with the spline so as to slide with respect to the transmission case 4, and the fork portion is engaged with one shift gear 11 so as to be relatively rotatable. Shift fork 1
When 5 is slid along the fork support shaft 16 to which the boss portion 15a of the shift fork 15 is fitted, the left and right shift gears 11 slide with the output shaft 7, and the shift fork 15 is moved to the boss portion 15a. A positioning ball 15b provided inside the fork supporting shaft 16 has a positioning annular groove 1 at the left end of the three positioning annular grooves 16a to 16c.
When the reverse gear is engaged with the gear 6a, either the left or right shift gear 11 corresponds to the input gear 1 of the intermediate transmission shaft 13.
3a, the turning force of the output shaft 7 is reversely rotated by the left intermediate transmission shaft 13 to the left turning gear 19a and is reversely transmitted by the right intermediate transmission shaft 13 to the right turning gear 19b. Swivel gears 19a, 19b
Is also driven in a rotation direction opposite to that of the straight transmission gear 9. Align the shift fork 15 with the positioning ball 15b.
Is in the neutral position in which it is engaged with the positioning annular groove 16b at the center of the three positioning annular grooves 16a to 16c, either the left or right shift gear 11 is disengaged from the corresponding input gear 13a of the intermediate transmission shaft 13, and the output shaft 13 From the power transmission to the left and right turning gears 19a and 19b.
When the shift fork 15 is brought to the deceleration position where the positioning ball 15b is engaged with the positioning annular groove 16c at the right end of the three positioning annular grooves 16a to 16c, either the left or right shift gear 11 has the corresponding turning gear 19a, 1
9b, and the turning power of the output shaft 7 is applied to the left turning gear 19a by the left shift gear 11 and the right shift gear 1
1 is transmitted to the right-side turning gear 19b, respectively, and the left and right turning gears 19a and 19b are both driven in the same rotation direction as the linear transmission gear 9. At this time, the rotation speeds of the left and right turning gears 19a and 19b are lower than the rotation speed of the straight transmission gear 9 due to the relationship of the gear ratio between the shift gear 11 and the turning gears 19a and 19b.

As shown in FIG. 3 etc., a swing brake 12 is attached to one end of the pair of intermediate transmission shafts 13.
Slewing brake 12 mounted on the left intermediate transmission shaft 13
Also, the swing brake 12 mounted on the intermediate transmission shaft 13 on the right side also includes the fixed-side brake body 12 provided on the portion 4a supporting one end side of the intermediate transmission shaft 13 of the transmission case 4.
and a movable side brake body 12b attached to the end of the intermediate transmission shaft 13. As shown in FIGS. 3 and 5, the fixed-side brake body 12a is formed as a separate component from the mission case 4 so as to include a non-circular brake hole 12c having a circumferentially uneven circumferential hole. So as to be retained by the retaining ring 12d so as not to come off and to be engaged with the mission case portion 4b forming the straight portion of the assembly hole. It is constituted by a ring member which is fixed so as not to rotate. The movable-side brake body 12b is configured by a non-circular member having an outer peripheral surface having a non-circular portion 12e having an uneven surface similar to the brake hole 12c of the fixed-side brake body 12a on one end side, and an intermediate transmission. It is attached to the shaft 13 by spline engagement so that it can rotate and slide integrally. The movable brake body 1 is moved by the operation fork 17 with which the fork portion 17a is engaged with the other end of the movable brake body 12b so as to be relatively rotatable and integrally slidable.
By sliding operation of 2b, the non-circular portion 1 of this is operated.
2e is configured to move in and out of the brake hole 12c of the fixed side brake body 12a.

As a result, either the left or right turning brake 1
2 also slides the movable side brake body 12b by swinging the operation fork 17 around the axis of the rotary support shaft portion 17b, and the non-circular portion 12e of the movable side brake body 12b brakes the fixed side brake body 12a. When entering the hole 12c, the movable side brake body 12b and the fixed side brake body 12a are engaged with each other in a non-rotatable manner due to these non-circular shapes, so that the turning gear 19a is passed through the intermediate transmission shaft 13 and the output gear 13b. , 19b enters the brake so that the brake is applied, and when the non-circular portion 12e of the movable side brake body 12b comes out from the brake hole 12c of the fixed side brake body 12a, the movable side brake body 12b and the fixed side brake body 12a.
By enabling relative rotation with the swivel gear 19
The brake is released so that the brakes a and 19b are released.

As shown in FIGS. 4 and 6, the boss portion 15a of the shift fork 15 for slidingly operating the shift gear 11 is described.
The base end side of the fork operating lever 41, whose free end side is engaged by the operation pin 40, is rotatably supported by the transmission case 4 by the rotation support shaft 42, and the rotation support shaft 42 projects outside the mission case. The proximal end side of the transmission switching arm 43 is integrally rotatably attached to the end of the transmission fork 15 so that the shift fork 15 can be slidably operated by the transmission switching arm 43. The rotation support shafts 17 of the operation forks 17 of the left and right swing brakes 12, respectively.
A brake operation arm 44 having a base end side integrally rotatably attached to an end portion of the transmission box b projecting outside is linked with a mode selection lever 46 by a link mechanism 45.

The mode selection lever 46 is provided so as to be swingable in the operating portion, and is configured to be operated by switching to three operation positions of a gentle turning position K, a brake turning position B, and a super-trust turning position S. I am doing it. Mode selection lever 46
Is operated to the gentle turning position K, the transmission switching arm 43 switches the shift fork 15 to the deceleration transmission position due to the operating force and the action of the link mechanism 45.
The brake operation arm 44 operates the movable side brake body 12b to the cut side. When the mode selection lever 46 is operated to the brake turning position B, the operation force and the action of the link mechanism 45 cause the transmission switching arm 43 to switch the shift fork 15 to the neutral position and the brake operating arm 44 moves. The side brake body 12b is operated to the entry side. When the mode selection lever 46 is operated to the super-trusted turning position S, the operation force and the action of the link mechanism 45 cause
The transmission switching arm 43 switches the shift fork 15 to the reverse rotation transmission position, and the brake operating arm 44
Operates the movable brake body 12b to the cut side.

As a result, when the mode selection lever 46 is switched to the gentle turning position K, the left and right shift gears 11 engage with the corresponding turning gears 19a and 19b, and the turning transmission mechanism 10 turns the output shaft 7. The left shift gear 11 causes the left turning gear 19a to move to the right shift gear 1a.
1 is transmitted to the right-side turning gears 19b respectively, and the low-speed transmission state is set so that the gears are reduced in speed and transmitted depending on the gear ratio between the shift gear 11 and the turning gears 19a and 19b. Is rotated in the same rotation direction as that of the straight transmission gear 9 at a lower speed than the straight transmission gear 9. At this time, the left and right turning brakes 12 are turned off, and the braking action on the turning gears 19a and 19b is released.

When the mode selection lever 46 is switched to the brake turning position B, the left and right shift gears 11 are disengaged from the input gear 13a of the intermediate transmission shaft 13 and the turning gears 19a and 19b, and the turning transmission mechanism 10 is moved from the output shaft 7 to the left and right. The turning gears 19a and 19b are turned off so as to cut off their transmission to the turning gears 19a and 19b. At this time, the left and right turning brakes 12 are turned on,
The brake is applied to the left and right turning gears 19a and 19b.

When the mode selection lever 46 is switched to the super transmission position S, the left and right shift gears 11 are moved to the intermediate transmission shaft 13.
Of the input gear 13a, and the turning transmission mechanism 10 reverses the turning power of the output shaft 7 to the left turning gear 19a by the left intermediate transmission shaft 13 and the right turning gear 19b by the right intermediate transmission shaft 13. In the reverse rotation transmission state, the left and right turning gears 19a and 19b are rotated in a rotation direction opposite to that of the straight transmission gear 9. At this time, the left and right swing brakes 12 are turned off, and the swing gear 1
The braking action on 9a and 19b is released.

As shown in FIG. 1 and the like, both the left steering clutch mechanism 20 and the right steering clutch mechanism 20 are provided with a transmission gear 21 that meshes with the traveling drive gears 30a and 30b, and rotate relative to the rotary shaft 9a. And a tubular transmission body 22 that is slidably fitted on the outside, an engagement clutch 23 provided between one end side of the transmission body 22 and the rectilinear transmission gear 9, and the other end side of the transmission body 22. And the turning gear 19
and a wet type multi-plate type friction clutch 24 provided between a and 19b.

The clutch spring 25 provided on the inner side of the end of the transmission 22 where the friction clutch 24 is located is the transmission 22.
Is slidably urged toward the straight transmission gear 9, the engagement clutch 23 is urged by switching to the entry side, and
The friction clutch 24 is configured to be biased by being switched to the disengaged side, and the fork portion is relatively rotatably engaged with the portion of the transmission 22 located between the friction clutch 24 and the transmission gear 21 and the transmission case 4 By swinging the operating fork 26, which is swingably supported by the clutch, the transmission member 22 slides due to the operating force and the operating force of the clutch spring 25, and the friction clutch 24 is moved.
The forward position where the meshing clutch 23 is operated while being turned on, the first turning position where the meshing clutch 23 and the friction clutch 24 are both turned off, and the friction clutch 24 is turned on while operating the meshing clutch 23. It is configured to switch to the second turning position that is operated to. In this way, the transmission body 22 slides to move straight to the first position.
Whether the operating position is the turning position or the second turning position, the transmission gear 21 is set by setting the tooth width of the transmission gear 21 and the traveling drive gears 30a and 30b and the sliding stroke of the transmission 22. Are traveling drive gears 30a, 30b
It keeps in mesh with each other.

Thus, in the left steering clutch mechanism 20 and the right steering clutch mechanism 20, the traveling drive gears 30a, 30a are driven by switching the transmission 22 to the straight traveling position.
0b is the transmission gear 21, the transmission body 22, the meshing clutch 2
The straight traveling input state is set so as to be interlocked with the straight traveling transmission gear 9 via 3, and the traveling devices 34a and 34b can be driven by the turning force from the straight traveling transmission gear 9. By switching the transmission member 22 to the first turning position, the traveling drive gears 30a and 30b are turned to a turning state so as to cut off transmission to the linear drive gear 9 and the turning gears 19a and 19b, and the traveling devices 34a and 34b. To the neutral state. By switching the transmission member 22 to the second turning position, the traveling drive gears 34a and 34b are engaged with the turning gears 19a and 19b via the transmission gear 21, the transmission member 22, and the friction clutch 24. Thus, it becomes possible to drive the traveling devices 34a and 34b by the turning force from the turning gears 19a and 19b, and to brake the traveling devices 34a and 34b by the turning brake 12.

As shown in FIG. 2, the left steering clutch mechanism 2
In the 0 and right steering clutch mechanism 20, the transmission member 22
The fork operating arm 50 is attached to the end of the rotary support shaft 26a of the fork 26 that operates the
The fork operating arm 50 is attached to the base end portion of the fork rotatably, and the fork operating arm 50 is a single-acting hydraulic cylinder 51 provided outside the mission case 4.
1 is configured to be rocked by a spring (not shown) that biases the hydraulic cylinder 51 toward the shortening side.
The transmission member 22 is configured to be slidable by means of. The hydraulic cylinder 51 of the left steering clutch mechanism 20.
And the hydraulic cylinder 51 of the right steering clutch mechanism 20 via an electromagnetically operated control valve 52.
Both hydraulic cylinders 5 are configured to supply hydraulic oil from
1, 51 is connected to the drain oil passage 53, and the operating portion of the variable relief valve 54 provided in the drain oil passage 53 and the operating portion of the control valve 52 are linked by a linkage mechanism 55 to form one steering lever. 56.

The steering lever 56 is provided in the operating portion so as to be capable of swinging in the lateral direction of the machine body, and is in the neutral position N.
A left first turning position L1 that swings to the left of the neutral position N, a left second turning position L2 that swings further to the left of the left first turning position L1, and a right side of the neutral position N. The swinging right first turning position R1 and the right first turning position R
It is configured to perform a switching operation to the right second turning position R2 that swings further to the right than 1.

When the steering lever 56 is operated to the neutral position N, the linkage mechanism 55 operates the control valve 52 to the neutral position, and the hydraulic cylinder 51 of the left steering clutch mechanism 20 and the hydraulic cylinder of the right steering clutch mechanism 20 are operated. 51 also operates the transmission 22 to the straight-ahead position.

When the steering lever 56 is operated to the first left turning position L1, the linkage mechanism 55 operates the control valve 52 to the left turning position, the hydraulic cylinder 51 of the right steering clutch mechanism 20 is not driven, and the left steering is performed. Hydraulic cylinder 51 of the directional clutch mechanism 20
Is driven toward the extension side to slide the transmission 22 toward the left turning gear 19a. At this time, when the linkage mechanism 55 operates the variable relief valve 54 to the open side and the transmission body 22 reaches the first turning position, the drain oil passage 53 drains the hydraulic oil from the hydraulic cylinder 51 to further increase the hydraulic cylinder 51. Stop stretching. As a result, the transmission body 20 of the right steering clutch mechanism 20 is in the straight traveling position, and the transmission body 22 of the left steering clutch mechanism 20 is in the first turning position.

When the steering lever 56 is operated to the second left turning position L2, the linkage mechanism 55 operates the control valve 52 to the left turning position, the hydraulic cylinder 51 of the right steering clutch mechanism 20 is not driven, and the left steering is performed. Hydraulic cylinder 51 of the directional clutch mechanism 20
Is driven toward the extension side to slide the transmission 22 toward the left turning gear 19a. At this time, the linkage mechanism 55 operates the variable relief valve 54 to the throttle side, the relief pressure of the drain oil passage 53 becomes high, and the hydraulic cylinder 51 moves the transmission 22 to the first position.
It becomes possible to perform the sliding operation toward the left turning gear 19a further than the turning position. As a result, the transmission body 22 of the right steering clutch mechanism 20 is in the straight traveling position, and the transmission body 22 of the left steering clutch mechanism 20 is in the second turning position.

When the steering lever 56 is operated to the right first turning position R1, the linkage mechanism 55 operates the control valve 52 to the right turning position, the hydraulic cylinder 51 of the left steering clutch mechanism 20 is not driven, and Hydraulic cylinder 51 of steering clutch mechanism 20
Is driven toward the extension side to slide the transmission member 22 toward the right turning gear 19b. At this time, when the linkage mechanism 55 operates the variable relief valve 54 to the open side and the transmission body 22 reaches the first turning position, the drain oil passage 53 drains the hydraulic oil from the hydraulic cylinder 51 to further increase the hydraulic cylinder 51. Stop stretching. As a result, the transmission body 22 of the left steering clutch mechanism 20 is in the straight traveling position, and the transmission body 22 of the right steering clutch mechanism 20 is in the first turning position.

When the steering lever 56 is operated to the right second turning position R2, the linkage mechanism 55 operates the control valve 52 to the right turning position, the hydraulic cylinder 51 of the left steering clutch mechanism 20 is not driven, and Hydraulic cylinder 51 of steering clutch mechanism 20
Is driven toward the extension side to slide the transmission member 22 toward the right turning gear 19b. At this time, the linkage mechanism 55 operates the variable relief valve 54 to the throttle side, the relief pressure of the drain oil passage 53 becomes high, and the hydraulic cylinder 51 moves the transmission 22 to the first position.
The right turning gear 19b can be slid further than the turning position. As a result, the transmission body 22 of the left steering clutch mechanism 20 is in the straight traveling position, and the transmission body 22 of the right steering clutch mechanism 20 is in the second turning position.

In other words, the turning transmission mechanism 10 is switched by the mode selection lever 46 to switch the turning mode between the slow turning mode, the brake turning mode, and the super trust turning mode, and the steering lever 56 controls the left steering clutch mechanism 20 and the right steering mode. The steering clutch mechanism 20 is operated to perform the airframe steering.
That is, even if the mode selection lever 46 is operated to any of the gentle turning position K, the brake turning position B, and the super-trust turning position S, if the steering lever 56 is operated to the neutral position N,
Both the left steering clutch mechanism 20 and the right steering clutch mechanism 20 are in the on-state for straight travel, and the left traveling drive gear 30a and the right traveling drive gear 30b are driven by the linear transmission gear 9 in association with the linear transmission gear 9. Left and right traveling devices 34a, 3
4b is driven at the same driving speed in the same driving direction, and the machine body goes straight. When the steering lever 56 is operated to the left first turning position L1 and the right first turning position R1, the operating direction of the steering lever 56 of the left steering clutch mechanism 20 and the right steering clutch mechanism 20 is opposite. The steering clutch mechanism 20 on the side is maintained in the on-state for straight traveling, and the steering clutch mechanism 2
The traveling drive gears 30a and 30b corresponding to 0 are driven by the straight transmission gear 9 and the steering on the side of the left steering clutch mechanism 20 and the right steering clutch mechanism 20 that is equal to the operating direction of the steering lever 56. The clutch mechanism 20 is in the turning disengaged state, and the traveling drive gears 30b and 30a corresponding to the steering clutch mechanism 20 are in the neutral state in which neither the straight transmission gear 9 nor the turning drive gears 19b and 19a are interlocked. , The traveling device 3 on the side opposite to the operating direction of the steering lever 56
4a and 34b are driven at the same drive speed as when traveling straight ahead, and the traveling device 3 on the side equal to the operating direction of the steering lever 56.
4a and 34b are in a neutral state, and the aircraft is in the steering lever 56.
Traveling device 34a in a neutral state in a direction equal to the operating direction of
34b is turned around the turning center.

When the mode selection lever 46 is operated to the gentle turning position K, the gentle turning mode is entered. That is, the turning transmission mechanism 10 is in a low speed transmission state, and the rotational power of the output shaft 7 is transmitted to the left and right turning gears 19a and 19b by the meshing of the shift gear 11 and the turning gears 19a and 19b. In this gentle turning mode, the steering lever 56 is moved to the left second turning position L.
2. When operated to the right second turning position R2, the steering clutch mechanism 20 of the left steering clutch mechanism 20 and the right steering clutch mechanism 20 on the side opposite to the operating direction of the steering lever 56 is in the straight-travel on state. The traveling drive gears 30a, 30b corresponding to the steering clutch mechanism 20 are driven by the straight transmission gears 9 so that the traveling devices 34a, 34b on the side opposite to the operating direction of the steering lever 56 travel straight. The steering clutch mechanism 20 on the side equal to the operating direction of the steering lever 56 among the left steering clutch mechanism 20 and the right steering clutch mechanism 20 is driven at the same speed as the time and enters the turning on state.
The traveling drive gears 30b and 30a corresponding to the steering clutch mechanism 20 are driven by the orbiting drive gears 19b and 19b in association with the orbiting drive gears 19b and 19b. Traveling device 3
4a is driven at a speed lower than that of the traveling device 34b in the same driving direction as the traveling device 34b on the side opposite to the operating direction of the steering lever 56, and the speed difference between the left and right traveling devices 34a and 34b thereby causes the body to move to the steering lever. Slowly turn in a direction equal to the operating direction of 56.

When the mode selection lever 46 is operated to the brake turning position B, the brake turning mode is set. That is, the turning transmission mechanism 10 is brought into a braking state, and the left and right turning gears 19a and 19b are braked by the turning brakes 12 corresponding thereto. In this brake turning mode,
When the steering lever 56 is operated to the left second turning position L2 and the right second turning position R2, one of the left steering clutch mechanism 20 and the right steering clutch mechanism 20 opposite to the operating direction of the steering lever 56. The steering clutch mechanism 20 is maintained in the on-state for straight travel, and the traveling drive gears 30a and 30b corresponding to the steering clutch mechanism 20 are driven by the straight transmission gear 9 to drive the left steering clutch mechanism 20 and the right steering mechanism. Clutch mechanism 20
Among these, the steering clutch mechanism 20 on the side equal to the operating direction of the steering lever 56 is in the turning on state, and the traveling drive gears 30a, 30 corresponding to this steering clutch mechanism 20 are turned on.
b is interlocked with the turning drive gears 19a, 19b and is braked by the turning brake 12 via the turning drive gears 19a, 19b, and the traveling devices 34a, 34b on the side opposite to the operation direction of the steering lever 56 travel straight ahead. Is driven at a speed equal to and the brakes are applied to the traveling devices 34a and 34b on the side equal to the operating direction of the steering lever 56.
The machine body makes a solid turn in a direction equal to the operating direction of the steering lever 56 with the traveling devices 34a, 34b in the braking state being turned inside.

The mode selection lever 46 is moved to the super-spot turning position S.
If operated to, it will be in super-confidential turning mode. That is,
The turning transmission mechanism 10 is in the reverse rotation transmission state, and the rotational force of the output shaft 7 is reversed by the intermediate transmission shaft 13 and transmitted to the left and right turning gears 19a and 19b. When the steering lever 56 is operated to the left second turning position L2 and the right second turning position L2 in the super-trust turning mode, the steering lever 56 of the left steering clutch mechanism 20 and the right steering clutch mechanism 20 is operated. The steering clutch mechanism 20 on the side opposite to the operating direction is maintained in the on-state for straight travel, and the traveling drive gears 30a, 30b corresponding to the steering clutch mechanism 20 are driven by the straight transmission gear 9 to drive left steering. Of the steering clutch mechanism 20 and the right steering clutch mechanism 20, the steering clutch mechanism 20 on the side that is equal to the operating direction of the steering lever 56 enters the turning on state, and the one corresponding to the steering clutch mechanism 20 travels. Drive gear 30b,
30a is driven by the turning drive gears 19b and 19a in conjunction with the turning drive gears 19b and 19a, and the traveling devices 34b and 34 on the opposite side of the operating direction of the steering lever 56.
a and the traveling devices 34a and 34b on the side equal to the operating direction of the steering lever 56 are driven in mutually opposite directions, whereby the body makes a super-spinning turn in the same direction as the operating direction of the steering lever 56.

The left and right shift gears 11 are attached to the output shaft 7 based on the attachment structure shown in FIGS. That is, the shift gear 11 is fitted onto the shaft portion 7a having the oval cross section through the mounting hole 11a, and the shift gear 11 is mounted on the output shaft 7 on both lateral sides of the shift gear 11 so that the shift gear 11 can be transmitted. The shift gear 11 is positioned so as to move together with the output shaft 7 with respect to the case 4. The lateral width W1 of the central portion of the mounting hole 11a of the shift gear 11 as viewed in the direction along the axis of the output shaft 7 is substantially equal to the lateral width of the shaft portion 7a, and the lateral width W2 at both ends is greater than the lateral width W1 of the central portion. It is formed in an hourglass shape, the shift gear 11 and the output shaft 7 rotate relative to each other by a set rotation angle a, and a part 7c of both side surfaces of the shaft portion 7a.
And the shift gear 11 are in contact with each other to rotate integrally. As the set rotation angle a, the shift gear 11
The input gear 13a of the intermediate transmission shaft 13 and the swing gear 19a,
Even when the teeth of the shift gear 11 and the teeth of the input gear 13a and the turning gears 19a, 19b abut each other when engaging the gears 19b, the gears 11, 13a, 19a, 19b have ends in the width direction. Due to the cam action of the chamfer provided, the shift gear 11 rotates relative to the output shaft 7, whereby the teeth of the shift gear 11 are easily rotated between the teeth of the input gear 13a and the turning gears 19a and 19b. The corner is set. As the set rotation angle a,
Preferably, it is set as follows. When the set rotation angle a ≧ 360 / Z (where Z = the number of teeth of the shift gear 11), the gear meshes with the counterpart gear within the range of the rotation angle a.

As shown in FIG. 1, a parking brake 60 is attached to one end of the output shaft 7. As shown in FIG. 3, the parking brake 60 is located outside the mission case 4 by being arranged outside the brake cover 61 formed so as to cover the swing brake 12 and attached to the case case 4. It is configured as an internal expansion type brake that includes a brake drum 62 that is installed and a brake shoe that is located inside the brake drum 62. When the brake lever 63 is operated to swing around an axis 63a, the brake cam rotates. When the brake shoe is operated, the diameter of the brake shoe is expanded to come into contact with the inner peripheral surface of the brake drum 62 to apply frictional braking, or the diameter of the brake shoe is reduced to release the brake of the brake drum 62. Cut into pieces.

In the brake drum 62, the boss portion of the brake drum 62 is integrally rotatably engaged with the angular shaft portion on one end side, and the other end side is externally fitted to the end portion of the output shaft 7 by spline engagement. The output shaft 7 is integrally and rotatably connected to the output shaft 7 by a connecting cylinder shaft 64 that is integrally and rotatably engaged.

As a result, when parking, the parking brake 60
When is switched to the entry side, the mode selection lever 46
The parking brake 60 is connected to the connecting cylinder shaft 64, the output shaft 7, the speed change gear 8, the straight transmission gear 9, and the meshing position, regardless of whether the operation position is the gentle turn position K, the brake turn position B, or the super-sight turn position S. Clutch 23, transmission 22, transmission gear 21
By braking the traveling drive gears 30a, 30b via the brakes, the left and right traveling devices 34a, 34b are braked.

As shown in FIG. 5 and the like, by forming a portion 7d of the output shaft 7 which is engaged with the connecting cylinder shaft 64 with a spline into an oval cross section, the inside of the connecting cylinder shaft 64 is formed inside the mission case 4. Oil passage 64 communicating with the space
a is formed inside the connecting cylinder shaft 64 on both lateral sides of the output shaft 7. As a result, the output shaft 7 is rotated by the turning transmission mechanism 10
When the sliding operation is performed for the switching operation of the
4 slides in and out, but at this time, the output shaft 7
With the sliding of the connecting cylinder shaft 64, the lubricating oil easily flows into the connecting cylinder shaft 64 through the oil passage 64a or easily flows out of the connecting cylinder shaft 64 to output the output shaft 7.
The resistance to movement in and out is reduced, and the output shaft 7 can be slid smoothly and the switching operation can be performed lightly and smoothly.

[Another Embodiment] FIG. 8 shows a swing brake 12 including another embodiment.
Is formed as a separate component from the mission case 4 like the fixed side brake body 12a shown in FIG.
The fixed side brake body 12a is fixed to the portion 4a so as not to be rotatable relative to it, and the movable side brake body 12b is attached to the intermediate transmission shaft 13 by spline engagement so as to be integrally rotatable and slidable. . The movable-side brake body 12b is configured by a non-circular member having a rectangular non-circular portion 12e at one end side when viewed in a direction along the axis of the intermediate transmission shaft 13, and the fixed-side brake body 12a has a cross-shaped brake hole. 12c is provided.

As a result, when the movable side brake body 12b is slid along the intermediate transmission shaft 13 and the non-circular portion 12e of the movable side brake body 12b enters into the brake hole 12c of the fixed side brake body 12a, these Due to the non-circular shape, the movable brake body 12b and the fixed brake body 12a engage with each other so that they cannot rotate relative to each other.
Is braked so that the turning gears 19a and 19b are braked via the intermediate transmission shaft 13 and the output gear 13b. Then, the non-circular portion 1 of the movable-side brake body 12b
When 2e comes out of the brake hole 12c of the fixed side brake body 12a, relative rotation between the movable side brake body 12b and the fixed side brake body 12a becomes possible, so that the swing brake 12 applies the brakes of the swing gears 19a and 19b. The brake will be released to release it.

The present invention can be applied to the case where the structure for transmitting power to the shaft provided with the shift gear 11 is various, such as the case where the auxiliary transmission M is not provided. Therefore, the output shaft 7 is referred to as the drive shaft 7.

The present invention can be applied not only to combine harvesters, but also to traveling power transmission devices for various vehicles such as root vegetable harvesters and transport vehicles, and these vehicles are collectively referred to as work vehicles.

[Brief description of drawings]

FIG. 1 is a schematic view of a traveling transmission device of a combine.

FIG. 2 is an explanatory view showing an operating structure of a steering clutch mechanism.

FIG. 3 is a sectional view of an arrangement portion of a shift gear, a parking brake, and a swing brake.

FIG. 4 is a sectional view of a shift gear operating portion.

FIG. 5 is a cross-sectional view of a swing brake operation unit.

FIG. 6 is an explanatory diagram of operation of a shift gear and a swing brake by a mode selection lever.

FIG. 7 is a sectional view of a shift gear mounting structure.

FIG. 8 is a sectional view of a swing brake including another embodiment.

[Explanation of symbols]

4 mission case 7 speed change gear 9 Straight transmission gear 10 Turning transmission mechanism 12 swing brake 12a Fixed side brake body 12b Movable brake body 13 Intermediate transmission shaft 19a Left turning gear 19b Right turning gear 30a Left drive gear 30b Right running drive gear 34a Left traveling device 34b Right traveling device 60 parking brake

Front page continuation (72) Inventor Yuji Kato 64 Ishizukitamachi, Sakai City, Osaka Prefecture Kubota Sakai Plant (56) References JP 2000-118434 (JP, A) JP 10-167106 (JP, A) Japanese Unexamined Patent Publication No. 4-321473 (JP, A) Actual Development No. 3-72089 (JP, U) (58) Fields investigated (Int.Cl. ⁷ , DB name) B62D 11/00

Claims (2)

(57) [Claims] Claim: What is claimed is: 1. A left operation which is switchable between a straight-traveling on-state in which a left traveling drive gear for driving a left traveling device is interlocked with a straight-traveling transmission gear, and a turning-on state in which the left traveling drive gear is interlocked with a left revolving gear. Equipped with a directional clutch mechanism, it is possible to switch between a right-hand drive gear that drives the right-hand drive device in a straight-travel on-state that links the straight-travel transmission gear to a straight-travel entry state that links the right-travel drive gear to the right-turn gear. Equipped with a right steering clutch mechanism , driving force for the straight transmission gear and the left and right turning gears
The drive shaft on the lower side in the power transmission direction.
The rotary power of the drive shaft is set to the left turning gear and the right turning gear.
With a pair of left and right intermediate transmission shafts that transmit separately,
Transmission from the drive shaft to the left turning gear and the right turning gear
The reverse rotation transmission state in which the rotational power of the drive shaft is reversely transmitted to the system by the intermediate transmission shaft to rotate the left swing gear and the right swing gear in a rotation direction opposite to that of the straight transmission gear, and the drive shaft of the drive shaft. A turning transmission mechanism that can switch between the left turning gear and the right turning gear by decelerating and transmitting the turning power to a low speed transmission state in which the left turning gear and the right turning gear are rotated in the same rotation direction as the straight transmission gear at a lower speed than the straight transmission gear A traveling transmission device for a work vehicle, comprising: the turning transmission mechanism, in which the drive shaft and the intermediate transmission shaft are disconnected from each other to cut off transmission to the left turning gear and the right turning gear. A traveling power transmission device for a work vehicle, which is configured to be switchable, in which a swing brake is attached to each of the left and right intermediate transmission shafts, and a parking brake is attached to the drive shaft. 2. A fixed-side brake body, in which the swing brake is formed as a separate component from the mission case and fixed to the mission case, and the fixed-side brake body, which is integrally and rotatably supported by the intermediate transmission shaft. And a non-circular movable brake body that engages and disengages with the brake body.
1 The transmission of the work vehicle described above.