JP2015134558A - Axle driving device of work vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a suitable arrangement configuration without interference between an ON/OFF operation device which implements ON/OFF of a clutch brake of a side clutch mechanism and a torque change operation device which implements transmission torque adjustment of an auxiliary clutch mechanism.SOLUTION: In an axle driving device 2 of a work vehicle, upon providing an auxiliary clutch device 30 which adjusts torque transmission between the left and right running axles 46L, 46R to the axle driving device, in addition to a side clutch mechanism 44, an ON/OFF operation device 130 which implements ON/OFF of side clutches 65L, 65R and side brakes 59R, 59L and a torque change operation device 68 which implements change of transmission torque through the auxiliary clutch device 30 are arranged separately to one side and the other side of a housing 35 of the axle driving device 2, respectively.

Description

  The present invention is provided with left and right side clutches for connecting and disconnecting power to the left and right traveling axles, and left and right side brakes capable of braking each output member from the left and right side clutches with the side clutch disengaged, A variable capacity auxiliary that can reduce a part of the driving force transmitted from the output member to one traveling axle to an arbitrary transmission torque and transmit it to the other traveling axle between the left and right traveling axles. More particularly, the present invention relates to an arrangement configuration of the side clutch / side brake on / off actuator and the torque changing operation device of the auxiliary clutch mechanism.

  Conventionally, in an axle drive device for a work vehicle such as a crawler vehicle such as a combiner, the driving force after shifting is transmitted to the left and right traveling axles via the left and right side clutches, and to each of the left and right side clutches. A steering technique based on a so-called side clutch system in which left and right side brakes are provided and a work vehicle is turned by turning on and off these side clutches and side brakes is known (for example, see Patent Document 1).

  According to the steering technology, the side clutch is engaged both inside and outside of the turn, the driving force is transmitted to both travel axles, and the "straight running mode" in which the work vehicle advances straight, and the side clutch outside the turn is in the engaged state. In this state, with only the side clutch inside the turn turned off, the running axle inside the turn freely rotates, and the `` slow turn mode '' in which the work vehicle turns gently with a large turning radius and the side brake inside the turn are turned on. As a state, it is possible to set the “quick turn mode” in which the traveling axle inside the turn is braked and the work vehicle is turned rapidly with a small turning radius. However, when driving in wetlands where the resistance between the ground contact section such as crawlers and tires and the field scene (hereinafter referred to as “running resistance”) increases, the traveling axle inside the turn becomes difficult to rotate and the turning radius becomes smaller. This makes it difficult to obtain the desired gentle turn, and when driving on deeper wetlands (hereinafter referred to as “super wetlands”), the running resistance on the inside of the turn is further increased, so the traveling axle inside the turn is constantly braked to make a sudden turn. However, the handling stability is significantly deteriorated.

  On the other hand, a variable capacity type auxiliary clutch mechanism capable of reducing the driving force of one traveling axle to an arbitrary transmission torque and transmitting it to the other traveling axle is interposed between the left and right traveling axles. Can be considered. According to this, even when traveling in a wet field or traveling in a super wet field, the traveling axle inside the turn can be forcibly driven to rotate by a transmission torque having a magnitude that overcomes the traveling resistance, Slow turning is ensured and steering stability is improved.

Japanese Patent Laid-Open No. 10-262417

  As described above, in order to provide the auxiliary clutch mechanism in the axle drive device in addition to the side clutch mechanism including the side clutch and the side brake, the side clutch mechanism and the side brake of the side clutch mechanism are provided in the housing of the axle drive device. An on / off operation device that performs on / off operation and a torque change operation device that changes the transmission torque transmitted through the clutch portion by the auxiliary clutch mechanism are disposed. Need to be configured.

The problem to be solved by the present invention is as described above. Next, means for solving the problem will be described.
That is, in claim 1, left and right side clutches for connecting and disconnecting power to the left and right traveling axles, and left and right side brakes capable of braking each output member from the left and right side clutches when the side clutch is disengaged. Between the left and right traveling axles, a part of the driving force transmitted from the output member to one traveling axle can be reduced to an arbitrary transmission torque and transmitted to the other traveling axle. In an axle drive device for a work vehicle provided with a capacity type auxiliary clutch mechanism, an on / off operation device for turning on / off the side clutch / side brake, and a torque change operation device for changing transmission torque by the auxiliary clutch mechanism Is arranged separately on one side and the other side of the housing of the axle drive device.
According to a second aspect of the present invention, in the auxiliary clutch mechanism, a plurality of clutch friction members are connected to the left and right intermediate transmission members that transmit the driving force from the output members to the left and right traveling axles, respectively. The clutch friction member group is formed by laminating each other, and the clutch friction member group is pressed by a pressing member so that an arbitrary transmission torque can be transmitted between the intermediate transmission members.
According to a third aspect of the present invention, the torque changing operation device supports the pressing member, a base portion of the pressing member, and a member support shaft horizontally mounted in the housing, and is rotatably supported by the base portion. A roller-like member-side rotator and a lever shaft that pushes the member-side rotator in the clutch friction member group pressing direction by rotation around the axis of a cam portion provided at one end.
5. The clutch friction member group is disposed between inner and outer double cylinders formed by opposingly forming cylindrical parts having different diameters on the left and right intermediate transmission members, and the inner and outer double cylinders. A first lubricating oil passage for introducing the lubricating oil in the housing into the inner cylindrical portion, and a second lubricating oil passage for guiding the lubricating oil from the inner cylindrical portion to the clutch friction member. It is to be prepared.
According to a fifth aspect of the present invention, the side brake is configured by locking a plurality of side brake friction members on each of an interlocking member interlocking with the traveling axle and a brake case fixed to the housing, and A brake lubricating oil passage having a shaft oil passage of the support shaft that rotatably supports the interlocking member and a radial oil passage that communicates with the shaft oil passage and opens on a surface of the support shaft; Through this, the lubricating oil in the housing is supplied toward the side brake friction member.

Since this invention was comprised as mentioned above, there exists an effect shown below.
That is, according to the first aspect, both operation systems of the on / off operation device and the torque changing operation device can be configured around the housing without interference.
According to claim 2, the clutch portion of the auxiliary clutch mechanism can be constituted by a normal friction multi-plate type clutch friction member group, and a complicated and large device for reducing a part of the driving force to an arbitrary transmission torque. This eliminates the need to reduce the cost of parts, improve the maintainability, and reduce the size of the housing by reducing the installation space.
According to claim 3, as compared with the conventional case, after engaging the tip of the lever member with the notch recess formed in the base of the pressing member, the pressing member is pushed in the clutch friction member group pressing direction. There is no worry of looseness due to parts accuracy and assembly accuracy, and friction caused by contact between the lever member and the pressing member can be reduced, so that the operation accuracy and operation efficiency can be greatly improved.
According to the fourth aspect, the lubricating oil can be effectively supplied to the clutch friction member group which is located between the inner and outer double cylindrical portions and is difficult to lubricate, and the life of the clutch friction member can be improved.
According to the fifth aspect, the lubricating oil can be effectively supplied to the side brake friction member group which is in the brake case and is difficult to lubricate, and the life of the side brake friction member can be improved.

It is a side view which shows the whole structure of the combine concerning this invention. It is also a plan view. It is front sectional drawing of an axle drive device. It is also a front view. It is a back view similarly. Similarly, it is a left side view. Similarly, it is a right side view. FIG. 4 is a rear cross-sectional view in the vicinity of a main transmission input unit. It is a back sectional view of a side clutch mechanism. It is a steering hydraulic circuit diagram. It is AA arrow sectional drawing of FIG. It is a back sectional view of a side clutch mechanism of another form. It is explanatory drawing of a side gear, Comprising: Fig.13 (a) is BB arrow sectional drawing of FIG. 9, FIG.13 (b) is a perspective view of a side gear. It is a back sectional view of an auxiliary clutch mechanism. It is a plane sectional view of a torque change operation device. FIG. 16 is a cross-sectional view taken along the line CC of FIG. 15 and shows a radial cross section of the cam body. FIG. 16A shows a case where the cam body comes into contact with the rotating roller at the plane portion, and FIG. This is a case where the rotated cam body contacts the rotating roller at the edge portion. It is plane sectional drawing of the periphery of the roller pin of another form. It is radial direction sectional drawing of a cam body at the time of providing a cam profile surface part. FIG. 19A is a sectional view in the radial direction of a rotating roller portion provided in place of the cam body. FIG. 19A shows the case of initial contact with the rotating roller, and FIG. 19B shows the case where the rotating roller is being pushed. It is.

Hereinafter, embodiments of the present invention will be described in detail.
The direction indicated by the arrow F in FIGS. 1 and 2 is the forward direction of the combine 1 that is a crawler vehicle, and the positions and directions of the members described below are based on this forward direction. The directions indicated by the arrows L and R in the middle respectively indicate the left direction and the right direction with reference to the forward direction.

First, the whole structure of the combine 1 which mounts the axle drive device 2 concerning this invention is demonstrated with reference to FIG. 1 thru | or FIG.
In the combine 1, crawler type traveling devices 4 </ b> L and 4 </ b> R are supported on the left and right of the track frame 3, and a machine base 5 is installed on the track frame 3.

  A cutting part 6 and a threshing part 7 are provided on the front and rear of the machine body. The cutting part 6 includes a cutting blade 8 and a culm transport mechanism 9 and the like, and a hydraulic cylinder 13 via a cutting frame 14. Can be moved up and down.

  A feed chain 10 is stretched to the left side of the threshing unit 7, and a handling cylinder 11 and a processing cylinder 12 are built in the right side of the feed chain 10, and a waste pipe is disposed behind the threshing unit 7. A waste disposal unit 16 that desires the end of the chain 15 is disposed so that the waste after the threshing is discharged backward.

  A grain tank 18 that carries the grain from the threshing section 7 through the cereal cylinder 17 is provided on the side of the waste disposal section 16. A rotatable discharge auger 19 is provided, and after the grain that has been cut from the reaping part 6 and processed in the threshing part 7 is stored in the grain tank 18, the grain is passed through the discharge auger 19. It is carried out of the machine.

  In addition, a driving unit 20 is provided between the harvesting unit 6 and the grain tank 18, and the driving unit 20 has a single operation that can be tilted left and right on the operation column 21 in front of the driver seat 23. The steering lever 22 protrudes upward, and left and right tilt switches 27 </ b> L and 27 </ b> R for detecting the left / right tilt direction of the steering lever 22 are disposed at the base of the steering lever 22. Further, an auxiliary clutch lever 24 that can arbitrarily set the value of the transmission torque of the auxiliary clutch mechanism 30 is disposed on the side of the steering lever 22.

  On the side of the driver's seat 23, a main transmission lever 25 that performs a shifting operation of the main transmission 29, an auxiliary transmission lever 26 that performs a shifting operation of the auxiliary transmission 31, and an on / off operation of the parking brake device 124. A parking brake lever 129 is provided in parallel.

  Further, below the driving unit 20, between the left and right crawler type traveling devices 4L and 4R, the engine 32 and the power from the engine 32 are shifted to connect the left and right crawler type traveling devices 4L and 4R. The axle drive device 2 to be driven is disposed.

Next, an outline of the power transmission configuration in the axle drive device 2 will be described with reference to FIGS.
In the axle drive device 2, the auxiliary transmission device 31, the side clutch mechanism 33, the speed reduction device 34, the auxiliary clutch mechanism 30 in the speed reduction device 34, and the like are accommodated in a housing 35. The main transmission 29 is mounted on a side surface.

  The main transmission 29 is a hydraulic continuously variable transmission (hydrostatic transmission), and its device case 29a is provided on the upper right side surface of the housing 35. The device case 29a has a variable volume. A type hydraulic pump 36 and a fixed displacement type hydraulic motor 37 are arranged in parallel in the vertical direction.

  The hydraulic pump 36 and the hydraulic motor 37 are fluidly connected to each other via a hydraulic circuit in a center section 29a1 whose one side is closed by the device case 29a, and a movable swash plate provided in the hydraulic pump 36. By changing the tilt angle of 36a, the discharge amount and discharge direction of the pressure oil from the hydraulic pump 36 to the hydraulic motor 37 can also be changed, and the engine power input to the pump shaft 38 of the hydraulic pump 36 is continuously variable. After being shifted, it is output from the motor shaft 39 of the hydraulic motor 37 parallel to the pump shaft 38. The movable swash plate 36a is linked to the main transmission lever 25 via a link mechanism 40.

  Further, the left end portion of the pump shaft 38 is connected to the input shaft 41 c 1 extending in the left and right directions on the same axis center via the coupling 120 in the support cylinder 121 provided on the upper surface of the housing 35. An engine output shaft 32a of the engine 32 is arranged in parallel to the input shaft 41c1, an output pulley 41a fixed on the engine output shaft 32a, and an input pulley 41c fixed on the input shaft 41c1. A belt 41b is wound between the engine 32 and the engine power from the engine 32 is input to the pump shaft 38 via the belt-type transmission device 41 having such a configuration.

  Thus, when the main transmission lever 25 is tilted, the inclination angle of the movable swash plate 36a changes, and the engine power input from the engine 32 to the pump shaft 38 via the belt-type transmission device 41 is converted into the main transmission power. Can be output steplessly from the motor shaft 39.

  Here, in the housing 35, parallel to the pump shaft 38 and the motor shaft 39, the sub transmission shaft 42, the intermediate shaft 43, the side clutch shaft 44, the left and right reduction shafts 45L and 45R, and the left and right crawler types are provided. The left and right traveling axles 46L and 46R equipped with the traveling devices 4L and 4R, respectively, are pivotally supported in a laterally extending manner.

  Among these, the motor shaft 39 has a left end penetrating into the housing 35. On the other hand, the boss portion of the output gear 47 is supported by the penetration portion via a bearing 79, and the output gear 47 is disposed on the same axis as the motor shaft 39. The penetration end of the motor shaft 39 is inserted through the center hole of the output gear 47 and connected through a spline, and the output gear 47 is fixed to the right end portion of the auxiliary transmission shaft 42. Is always engaged.

  In the auxiliary transmission 31, a sliding gear 49 including a gear portion 49 a, a gear portion 49 b, and a tooth portion 49 c in order from the right on the auxiliary transmission shaft 42 is slidable in the axial direction and relatively A spline fitting is made so as not to rotate, and a loose fitting gear 50 is provided on the left side of the sliding gear 49 so as to be relatively rotatable. On the other hand, on the intermediate shaft 43, a low speed gear 51, a medium speed gear 52, and a high speed gear 53 are fixed in order from the right, and the loose gear 50 is always meshed with the high speed gear 53.

  As a result, the sliding gear 49 is slid, and the low-speed gear trains 49a and 51 in which the gear portion 49a is engaged with the low-speed gear 51, and the medium-speed gear in which the gear portion 49b is engaged with the medium-speed gear 52. Three sub-speeds are formed from the rows 49b and 52 and the high-speed gear trains 50 and 53 in which the tooth portions 49c are engaged with the tooth portions 50a of the loose fitting gear 50.

  Then, by selecting any one of the low-speed gear trains 49 a and 51, the medium-speed gear trains 49 b and 52, and the high-speed gear trains 50 and 53, the motor shaft 39 is connected via the output gear 47 and the gear 48. The main transmission power input to the transmission shaft 42 can be transmitted to the intermediate shaft 43 as auxiliary transmission power.

  Similarly to the main transmission 29, the sliding gear 49 is linked to the auxiliary transmission lever 26 via a link mechanism 54, and the sliding gear 49 is tilted to operate the sliding gear 49. The moving gear 49 is slid so that one of the low-speed gear trains 49a and 51, the medium-speed gear trains 49b and 52, and the high-speed gear trains 50 and 53 can be selected.

  Further, the auxiliary transmission shaft 42 has a left end portion that protrudes outwardly through the housing 35, and a PTO output pulley 123 is provided at the protruding end via a PTO clutch 122. The main transmission power output from the transmission 29 can be output as PTO power from the PTO output pulley 123 to a working machine (not shown).

  On the other hand, the right end portion of the intermediate shaft 43 penetrates the right side surface of the housing 35 and protrudes outward, and the inwardly expanding parking brake device 124 is provided at the protruding end. The parking brake arm 125 for operating the parking brake device 124 is constantly urged downward by a return spring 126 having one end connected to the middle portion of the parking brake arm 125, as shown in FIG. The parking brake lever 129 is connected through a link mechanism (not shown).

  Accordingly, when the parking brake lever 129 is tilted, the parking brake arm 125 rotates from the position 127 to the position 128 against the elastic force of the return spring 126, and the parking brake device 124 is activated. The intermediate shaft 43 is locked so that the combine 1 can be surely stopped even on a slope.

  Further, the sub-transmission power transmitted from the engine 32 via the main transmission 29 and the sub-transmission 31 configured as described above is transmitted from the side clutch mechanism 33 to the reduction device 34 as described in detail later. Is branched toward the left and right traveling axles 46L and 46R.

  Each of the traveling axles 46L and 46R can be independently driven, freely rotated, or braked by turning on and off the left and right side clutches 65L and 65R and the left and right side brakes 59L and 59R. The turning mode can be set, and the turning mode can be set to any one of the straight traveling mode, the gentle turning mode, and the sudden turning mode.

  At this time, by operating the auxiliary clutch mechanism 30, as described in detail later, the side clutch 56L (56R) of the side clutch 65L / 65R is output from the side gear 56L (56R) and the one traveling axle 46L (46R) is output. The driving power can be reduced to an arbitrary transmission torque and transmitted to the traveling axle 46R (46L) on the clutch disengagement side of the side clutches 65L and 65R.

  As a result, even when the running resistance is large, such as when driving on wetlands, the running axle that is in a freely rotating state inside the turn is forcibly rotated by applying a predetermined transmission torque to obtain a stable turning performance. Can do it.

Next, the side clutch mechanism 33 and the speed reduction mechanism 34 will be described in detail with reference to FIGS. 3, 4, 9 to 13.
First, the structure of each mechanism will be described.
As shown in FIGS. 3 and 9 to 11, in the side clutch mechanism 33, the side clutch shaft 44 can be pivoted back and forth in the housing 35 via a pair of bearings 171 </ b> L and 171 </ b> R at the left and right ends. A center gear 55 having dog claw portions 55La and 55Ra on both left and right outer sides is press-fitted and fixed to be relatively non-rotatable at a substantially central portion on the left and right sides of the side clutch shaft 44. 55 is integrated with the side clutch shaft 44 so that it can rotate in the housing 35. The center gear 55 is always meshed with the medium speed gear 52.

  Further, left and right side gears 56L and 56R having dog claw portions 56La and 56Ra on the inner side are loosely fitted on the left and right outer sides of the center gear 55 so as to be slidable on the side clutch shaft 44 in the axial direction. Has been.

  The left and right side gears 56L and 56R are slid, and the dog pawl portions 56La and 56Ra are engaged with and separated from the dog pawl portions 55La and 55Ra of the center gear 55, respectively, so that the clutch is turned on and off. Left and right side clutches 65L and 65R are formed so that they can be performed.

  On the other hand, between the left and right outer end cylindrical portions 56Lb and 56Rb of the left and right side gears 56L and 56R and the cylindrical brake case portions 35a and 35b protruding inward from the left and right inner walls of the housing 35, Each side brake friction member group 64L and 64R is formed by laminating the side brake friction members so as to be slidable in the axial direction and not relatively rotatable.

  The side gears 56L and 56R are slid, and the side brake friction members in the side brake friction member groups 64L and 64R are pressed and separated by the pressing protrusions 56Lc and 56Rc so that the brake is turned on and off. The left and right side brakes 59L and 59R of friction multi-plate type are formed.

  A return spring 104 for urging the side gears 56L and 56R inward toward the center gear 55 is provided in the outer end cylindrical portions 56Lb and 56Rb. Usually, the pressing protrusions 56Lc and 56Rc are provided. Are separated from the side brake friction member groups 64L and 64R, and the dog claw portions 56La and 56Ra are brought close to and engaged with the dog claw portions 55La and 55Ra.

  Furthermore, outer peripheral grooves 56Ld and 56Rd are recessed along the outer periphery of the left and right side gears 56L and 56R, and shifters 60L and 60R are fitted into the outer peripheral grooves 56Ld and 56Rd, respectively. As shown in FIG. 11, the shifter 60L has a pair of front and rear in an outer circumferential groove 56Ld, and is sandwiched from the front and rear by lower ends 135a and 135b of a substantially U-shaped fork 135L that opens downward in a side view. These are locked via support pins 136a and 136b. The shifter 60R is also locked to the fork 135R with the same configuration.

  The left and right forks 135L and 135R are connected to steering cylinders 61L and 61R that can be driven by a steering hydraulic circuit 143, which will be described later, so that the side gears 56L and 56R slide left and right on the side clutch shaft 44. I can do it. The sliding stroke at this time is linked to the steering hydraulic circuit 143 so as to change according to the magnitude of the tilt angle of the steering lever 22.

  That is, the side gears 56L and 56R slide to the left and right with a sliding stroke corresponding to the operating stroke of the steering cylinders 61L and 61R, or the side brakes 65L and 65R are turned on or off, or the side brakes 59L and As described above, each of the traveling axles 46L and 46R is independently set to any one of a driving state, a free rotation state, and a braking state.

The speed reducer 34 is arranged on the power transmission downstream side of the side clutch mechanism 33 having such a configuration.
Large gears 57L and 57R are fixed to inner ends of the left and right reduction shafts 45L and 45R, respectively, and the large diameter gears are fixed to outer ends of the reduction shafts 45L and 45R. Small-diameter gears 58L and 58R having a smaller diameter than 57L and 57R are fixed.

  Among these, the large-diameter gears 57L and 57R are set at a position where the tooth width is set narrower than that of the side gears 56L and 56R, and the meshing is maintained even if the side gears 56L and 56R slide as described above. The side gears 56L and 56R are always meshed with each other. On the other hand, the small-diameter gears 58L and 58R are always meshed with left and right axle gears 66L and 66R fixed to the inner ends of the traveling axles 46L and 46R, respectively.

  As a result, the first reduction gear trains 56L and 57L including the side gear 56L and the large-diameter gear 57L having a larger diameter than the side gear 56L are added to the small-diameter gear 58L and the axle gear 66L having a larger diameter than the small-diameter gear 58L. The second reduction gear trains 58L and 66L comprising the above are connected in series, and the driving force from the side gear 56L can be transmitted to the left traveling axle 46L after being decelerated in two stages. Similarly, for the right traveling axle 46R, the second reduction gear trains 58R and 66R are connected to the first reduction gear trains 56R and 57R, and the driving force from the side gear 56R is decelerated in two stages and then the right It can be transmitted to the traveling axle 46R.

  The auxiliary clutch mechanism 30, which will be described in detail later, is interposed between the large-diameter gears 57L and 57R in the reduction gear 34.

Next, the operation configuration of the side clutch mechanism 33 will be described.
As shown in FIGS. 3, 4, and 9 to 11, the steering hydraulic circuit 143 that operates the side clutch mechanism 33 includes an on / off operating device 130 that operates the forks 135L and 135R, and the steering A cylinder operating circuit portion 148 that supplies and discharges hydraulic oil to / from the on / off operating device 130 by tilting the lever 22, and the cylinder operating circuit portion 148 is connected to the steering lever 22 and the left and right tilt switches 27L and 27R. Linked together.

  A fork shaft 132L extends forward from the front portion of the fork 135L, and the fork shaft 132L is rotatably supported on the front wall of the housing 35. It protrudes outward from the front surface of 35 toward the front. On the other hand, from the rear portion of the fork 135L, the support shaft 140 extends rearward on the same axis as the fork shaft 132L, and is rotatably supported in the housing 35.

  As a result, when the left fork shaft 132L is rotated, the shifters 60L and 60L are pushed in the left-right direction via the support pins 136a and 136b arranged eccentrically downward, and the left side gear 56L is moved on the side clutch shaft 44. Can be slid in the axial direction. The same applies to the right fork shaft 132R, and the shaft end protrudes outward from the front surface of the housing 35. When the fork shaft 132R is rotated, the fork shaft 132R is turned through the fork 135R. The shifters 60R and 60R are pushed in the left-right direction, and the right side gear 56R can be slid on the side clutch shaft 44 in the axial direction.

  The on / off operation device 130 rotates such left and right fork shafts 132 </ b> L and 132 </ b> R, and is disposed in the upper half of the front surface of the housing 35.

  The on / off operating device 130 includes a device case 131 fastened and fixed to the upper front portion of the housing 35 by a plurality of bolts 149, and a pair of left and right steering cylinders 61L arranged side by side in the device case 131. 61R, and a pair of left and right connecting arms 133L and 133R interposed between the lower ends of the piston rods 134L and 134R of the steering cylinders 61L and 61R and the left and right fork shafts 132L and 132R.

  The steering cylinders 61L and 61R are inserted into the cylinders 139L and 139R so that the pistons 138L and 138R can slide up and down, and the piston rods 134L and 134R are moved downward from the lower end surfaces of the pistons 138L and 138R. It is protruding. Further, in the cylinders 139L and 139R, oil chambers 141L and 141R and spring chambers 142L and 142R are formed above and below the pistons 138L and 138R, respectively, and piston rods in the spring chambers 142L and 142R are formed, respectively. A return spring 137 is wound around 134L and 134R.

  The cylinder operating circuit portion 148 supplies and discharges hydraulic oil to and from the oil chambers 141L and 141R, and is attached to a body frame (not shown) of the combine 1. The oil chambers 141L and 141R are connected to the 2-port 3-position electromagnetic switching valve 151 in the cylinder operating circuit section 148 via pipe oil passages 153 and 152 having line filters 147 on the way. Yes.

  The electromagnetic switching valve 151 is provided with a spool 151a that can be slid back and forth by electromagnetic solenoids 154 and 154. The electromagnetic solenoids 154 and 154 are connected to the left and right tilt switches 27L and 27R via a controller 155. ing.

  Further, the electromagnetic switching valve 151 is formed with a pump port 157 for supplying hydraulic oil and a drain port 158, and the pump port 157 among them is connected to the engine via an oil passage 159 having a line filter 147 in the middle. The suction side of the hydraulic pump 145 communicates with the filter 146 in the oil reservoir 144 of the housing 35 via the oil passage 160. The drain port 158 is communicated with the oil reservoir 144 through an oil passage 162.

  In the steering cylinders 61L and 61R, oil passages communicated with the oil chambers 141L and 141R when the pistons 138L and 138R inside thereof reach a stroke corresponding to the clutch disengagement positions of the side clutches 65L and 65R. 156 is provided, and a variable relief valve 150 is interposed in the middle of the oil passage 156 up to the oil reservoir 144, and the oil pressure in the oil chambers 141L and 141R is changed from zero to a predetermined value. It can be set up to.

  Further, the relief valve 150 communicates with the oil sump 144 via the oil passage 162, and the relief pressure adjusting spring 150 a is provided at the base of the steering lever 22 via a link mechanism 163. Connected to the rotating cam 164.

  When the steering lever 22 is tilted left and right, the rotating cam 164 converts the tilting and turning motion of the steering lever 22 into a linear motion and transmits it to the link mechanism 163. At this time, the linear momentum also increases in proportion to the increase in the tilting operation amount. Furthermore, the relief pressure adjustment spring 150a of the relief valve 150 is compressed by the operation force input to the link mechanism 163, and the relief set pressure is adjusted.

  In such a configuration, when the steering lever 22 is at the center 165 at the left and right, both the left and right tilt switches 27L and 27R are OFF, the electromagnetic switching valve 151 is set at the position 170a, and the oil chamber Both 141L and 141R lead to the oil sump 144. Then, the pistons 138L and 138R are held at the contracted position 70 by the elastic force of the return spring 137, the piston rods 134L and 134R do not extend, and the fork shafts 132L and 132R do not rotate. Therefore, both the side gears 56L and 56R are slid inward by the return spring 104, and the dog claw portions 56La and 56Ra engage with the dog claw portions 55La and 55Ra of the center gear 55, so that both sides The clutches 65L and 65R are engaged.

  Then, the auxiliary transmission power from the intermediate shaft 43 is transmitted from the medium speed gear 52 to the both side gears 56L and 56R via the center gear 55, and then decelerated by the reduction gear 34 before moving left and right. It is transmitted to the axles 46L and 46R and set in a driving state, and the left and right crawler type traveling devices 4L and 4R are driven at a constant speed to enter the straight traveling mode.

  For example, when the steering lever 22 tilts to the left and reaches the position 166, only the tilt switch 27L is turned on, and an ON signal is input to the controller 155, and the left turning direction signal from the controller 155 The electromagnetic solenoids 154 and 154 are operated, the electromagnetic switching valve 151 is set to the position 170b, and the oil supply to the oil chamber 141L is started. Therefore, while the right side clutch 65R remains in the engaged state, only the left side gear 56L is slid outward, and the dog claw portion 56La is separated from the dog claw portion 55La of the center gear 55, The side clutch 65L is turned off.

  At this time, since the rotating cam 164 is provided with an interchangeable portion, the tilting operation of the steering lever 22 is not transmitted to the link mechanism 163, and the relief pressure adjusting spring 150a of the relief valve 150 is not compressed and is relieved. The set pressure is maintained at zero. For this reason, the piston 138L stops moving before the oil chambers 141L and 141R open to the oil passage 156. Therefore, the side gear 56L does not reach the side brake friction member in the left side brake friction member group 64L and remains separated, and the left side brake 59L is also turned off. Yes.

  Then, the auxiliary transmission power transmitted through the medium speed gear 52 and the center gear 55 is transmitted to the right side gear 56R, then decelerated by the reduction gear 34, and then transmitted to the right traveling axle 46R. The driving state is set, and the right crawler traveling device 4R is driven. On the other hand, the auxiliary transmission power is not transmitted to the left side gear 56L at all, and the left side brake 59L is also in the off state. Therefore, the left traveling axle 46L is set in a free rotation state, and the left crawler traveling The device 4L is not driven. For this reason, the combine 1 turns left slowly with a large turning radius and enters a gentle turning mode. The interchangeable portion of the rotating cam 164 is set so as to disappear when the steering lever 22 reaches the position 166.

  Further, when the steering lever 22 is tilted largely to the left beyond the position 166, only the tilt switch 27L is kept on, and the steering lever 22 is tilted via the rotating cam 164. The operation is transmitted to the link mechanism 163, and the relief pressure adjusting spring 150a of the relief valve 150 is compressed according to the tilting operation amount, and the communication between the oil chambers 141L and 141R and the oil reservoir 144 is blocked. For this reason, the steering cylinder 61L is further extended, the right side clutch 65R remains in the engaged state, and only the left side gear 56L is further slid outward, and the left side brake friction member group 64L The side brake friction members come into pressure contact with each other, and the left side brake 59L is turned on.

  Then, while the right crawler type traveling device 4R is driven, the left side gear 56L is fixed by the left side brake 59L, and the left traveling axle 46L is set to a braking state via the speed reducer 34, and the left The crawler traveling device 4L is braked. For this reason, the combine 1 turns left rapidly with a turning radius smaller than that in the slow turning mode, and enters the sudden turning mode.

  In the rapid turn mode, the amount of compression of the relief pressure adjusting spring 150a of the relief valve 150 is increased in proportion to the tilt angle of the steering lever 22, so that the set pressure is increased. Therefore, in the oil chambers 141L and 141R As the pressure increases, the extension amount of the steering cylinder 61L increases, the braking force by the side brake 59L increases, and when the maximum tilt angle of the position 167 is reached, the left crawler type traveling device 4L is completely locked. It is set so that.

  The same applies to the right turn. When the steering lever 22 tilts to the right and reaches the position 168, the electromagnetic switching valve 151 is set to the position 170c, and the combine 1 turns right in the slow turn mode. Further, when the steering lever 22 is tilted largely to the right beyond the position 168, the set pressure of the relief valve 150 is increased, and the combine 1 can turn right in the rapid turn mode, and when it reaches the position 169, The crawler type traveling device 4R is completely locked.

Further, various configurations of support, meshing, and lubrication in the side clutch mechanism 33 having the above-described structure and operation configuration and other forms thereof will be described.
As shown in FIGS. 3 and 9, the center gear 55, which is an input member to the side clutches 65L and 65R, rotates integrally with the side clutch shaft 44 via the pair of bearings 171L and 171R as described above. However, instead of this, as shown in FIG. 12, the left and right end portions of the side clutch shaft 44A are inserted and fixed in the housing 35, and at the left and right central portions of the side clutch shaft 44A, The center gear 55A may be externally fitted through a bearing 172 so as to be relatively rotatable.

  Thereby, the center gear 55A can be supported as a separate member on the fixed side clutch shaft 44A so as to be relatively rotatable.

  As shown in FIGS. 9, 11, and 13, in the side gears 56 </ b> L and 56 </ b> R that are output members of the side clutches 65 </ b> L and 65 </ b> R, the dog pawl portions 56 </ b> La and 56 </ b> Ra are the large-diameter gears 57 </ b> L and 57 </ b> R of the reduction device 34. From the side surfaces 56Lh and 56Rh of the tooth portions 56Le and 56Re that mesh with the side portions 56Lh and 56Rh, the side clutch shaft 44 protrudes inward in the axial center direction, and a plurality of them are arranged around the axial center at equal intervals.

  In the present embodiment, the dog claw portions 56La and 56Ra are arranged at intervals of 90 degrees with respect to the 12 teeth 56Lf and 56Rf forming the outer periphery of the tooth portions 56Le and 56Re. -It is arranged on the side surfaces 56Lh and 56Rh of 56Rf. The protruding heights 173 in the dog claw portions 56La and 56Ra are substantially uniform in both the circumferential direction and the radial direction, and protruding surfaces 56Lg and 56Rg parallel to the side surfaces 56Lh and 56Rh are formed.

  Here, conventionally, the dog claw portions of the side gears 56L and 56R have a low protruding height in the vicinity of the outer periphery due to processing of the outer diameter of the gear and the like. It was made to supplement by forming wide across the side surface of each tooth. For this reason, the interval around the shaft center between the adjacent dog claw portions of the side gears 56L and 56R becomes narrow, and if the relative rotational speed difference between the center gear 55 and the side gears 56L and 56R is large, the gap between the dog claw portions of both gears. The meshing became difficult and the fit was worse.

  Therefore, as described above, the dog claw portions 56La and 56Ra have a substantially uniform projection height 173, so that the dog claw portions 56La and 56Ra are formed narrowly only on the side surfaces of the single teeth 56Lf and 56Rf. However, sufficient meshing strength can be ensured, and thereby the interval 175 around the axis between the adjacent dog claw portions 56La and 56Ra can be enlarged.

  As shown in FIG. 9, in the side clutch shaft 44 in which the side brake friction member groups 64 </ b> L and 64 </ b> R of the side brakes 59 </ b> L and 59 </ b> R are arranged on the outer periphery, a shaft center oil passage 176 is disposed on the axis of the side clutch shaft 44. A plurality of radial oil passages 177L formed through the shaft oil passages 176 and radially extending around the shaft oil passages 176 at the inner positions of the left and right side brake friction member groups 64L and 64R. 177R is perforated, and a brake lubricating oil passage 180 is formed from the axial center oil passage 176 and the radial oil passages 177L and 177R.

  Oil pockets 178L and 178R are formed between the left and right ends of the side clutch shaft 44 and the housing 35. The lubricating oil flowing into the pockets radiates from the axial oil passage 176 by centrifugal force. The oil passes through the oil passages 177L and 177R, and is supplied into the internal spaces 179L and 179R of the outer end cylindrical portions 56Lb and 56Rb of the side gear 56, and further into the side brake friction member groups 64L and 64R from the internal spaces 179L and 179R. I am trying to supply.

  Note that the oil in the oil reservoir 144 in the housing 35 may be directly guided to the oil pockets 178L and 178R, and drain oil on the way from the steering hydraulic circuit 143 to the oil reservoir 144 passes through here. You may comprise.

  Furthermore, as the brake lubricating oil passage 180, through oil passages 181L and 181R that penetrate the brake case portions 35a and 35b in the radial direction are penetrated, or grooves (not shown) are formed on the outer peripheral surfaces of the brake case portions 35a and 35b. May be recessed.

  As a result, the oil in the oil sump 144 that is swept up and spattered by the gear in the housing 35 is easily introduced into the brake case portions 35a and 35b, and the amount of lubricating oil for the side brake friction member groups 64L and 64R is reduced. Can be increased.

  That is, the side brakes 59L and 59R include outer end cylindrical portions 56Lb and 56Rb that are interlocking members interlocked with the travel axles 46L and 46R, and brake case portions 35a and 35b that are brake cases fixed to the housing 35, respectively. A plurality of side brake friction members are engaged with each other, and an axial center oil passage 176 of a side clutch shaft 44 that is a support shaft that rotatably supports the outer end cylindrical portions 56Lb and 56Rb, and the shaft center A brake lubricating oil passage 180 having radial oil passages 177L and 177R communicating with the oil passage 176 and opening on the surface of the side clutch shaft 44 is provided, and lubrication in the housing 35 is performed via the brake lubricating oil passage 180. Since oil is supplied toward the side brake friction member, it is hard to lubricate in the brake case portions 35a and 35b. The id brake friction member groups 64L · 64R, the lubricating oil can be effectively supplied, it is possible to life improvement of the side brake friction member.

Next, the auxiliary clutch mechanism 30 will be described in detail with reference to FIGS. 3, 5, 11, 14 to 19.
As shown in FIGS. 3 and 14, the auxiliary clutch mechanism 30 is a friction multi-plate type similar to the side brakes 59L and 59R, and is a clutch friction member group provided between the left and right large-diameter gears 57L and 57R. 67 and a fork portion 75b that presses the clutch friction member group 67. The fork portion 75b is included in the torque changing operation device 68.

  As shown in FIG. 14, in the clutch friction member group 67, the inner periphery of the cylindrical clutch case portion 57La projecting rightward from the middle in the radial direction on the inner surface of the left large-diameter gear 57L. Is provided with a plurality of ring-shaped clutch friction members 77, and the clutch friction members 77 slide in the axial direction so that the engaging portions formed on the outer peripheral edges of the clutch friction members 77 are hooked in the long grooves of the clutch case portion 57La. It is possible and is locked so as not to be relatively rotatable.

  On the other hand, on the inner surface of the right large-diameter gear 57R, a plurality of ring-shaped clutches protrude from the vicinity of the base portion to the left side of the drawing and are inserted into the clutch case portion 57La on the outer periphery of the cylindrical clutch case portion 57Ra. A friction member 78 is arranged, and the clutch friction member 78 is locked through a spline so as to be slidable in the axial direction and not relatively rotatable.

  These clutch friction members 77 and 78 are laminated together to form the clutch friction member group 67. That is, the clutch friction member group 67 is disposed between the inner and outer double cylindrical portions 62 formed by inserting the opening side of the right clutch case portion 57Ra into the opening side of the left clutch case portion 57La. A pressure receiving surface of the clutch friction member group 67 is formed on the inner surface of the left large-diameter gear 57L corresponding to the inside of the base portion of the clutch case portion 57La.

  As shown in FIGS. 3, 11, 14 to 16, in the torque changing operation device 68, a fork shaft 76 is horizontally mounted in the housing 35 in parallel with the left and right reduction shafts 45 </ b> L and 45 </ b> R. A pipe-like base portion 75a of the clutch fork 75 is externally fitted on the outer periphery of the fork shaft 76, and a roller pin 182 penetrates from the base portion 75a to the fork shaft 76 in the radial direction.

  In the roller pin 182, a rotating roller 183 is rotatably supported by a base end portion 182a protruding from the base portion 75a on one end side thereof, and is prevented from coming off by a head portion 182a1. On the other hand, a retaining ring 184 for assembly is externally fitted to the protruding end 182b projecting from the base 75a on the other end side of the roller pin 182, and the roller pin 182 is positioned and fixed to the fork shaft 76 by the retaining ring 184. .

  Here, the left and right end portions 76a and 76b of the fork shaft 76 are slidable in the axial direction into cylindrical support members 185L and 185R inserted into the left and right recesses 35c and 35d of the housing 35, respectively. Interpolated. Between the bottom surfaces of the support members 185L and 185R and the outer end surfaces of the left and right end portions 76a and 76b, movement gaps 186L and 186R for moving the fork shaft 76 in the axial direction are formed. ing.

  As a result, the clutch fork 75, the fork shaft 76 that supports the base portion 75a of the clutch fork 75, and the rotating roller 183 that is rotatably supported on the base portion 75a are integrated in the axial direction. Can move.

  From the movable clutch fork 75, the fork portion 75b extends toward the clutch case portion 57Ra, and the U-shaped opening 75b1 of the fork portion 75b is connected to the clutch case portion 57Ra. Are arranged so as to straddle the outer peripheral surface. Further, a thrust bearing 71 is fitted on the clutch case portion 57Ra between the left side surface at the front end of the fork portion 75b and the right side surface of the clutch friction member group 67.

  Thus, by moving the clutch fork 75 in the direction of the arrow 187, the clutch friction member group 67 that is rotating can be pressed from the right by the fork 75b while the friction is suppressed by the thrust bearing 71.

  On the other hand, at the rear part of the housing 35, a lever shaft 73 is pivotally supported in the front-rear direction perpendicular to the fork shaft 76, and the front end portion of the lever shaft 73 is divided by a dividing plane parallel to the axis. Thus, a substantially semi-cylindrical cam body 73a is formed. In addition, as shown in FIG. 16 (a), the portion of the flat surface portion 73a1 of the cam body 73a that is close to the rotational axis is in contact with the outer peripheral surface of the rotating roller 183 in the initial state.

  Here, on the fork shaft 76, a biasing spring 188 is wound between the left end of the base portion 75a of the clutch fork 75 and the inner wall of the housing 35 in the vicinity of the left recess 35c. Due to the elastic force of the spring 188, the clutch fork 75, the fork shaft 76, and the rotating roller 183 are constantly urged in the direction opposite to the arrow 187, and the urging force is applied by the flat portion 73a1 of the cam body 73a. I try to catch it.

  As a result, when the lever shaft 73 rotates, the rotary roller 183 is pushed while rotating along the outer peripheral surface of the cam body 73a while resisting the elastic force of the biasing spring 188. The fork shaft 76 can be moved in the axial direction.

  Further, the rear end of the lever shaft 73 protrudes outside the housing 35, and a base portion 72a of the clutch control lever 72 is fitted and fixed to the protruding portion, and the tip of the clutch control lever 72 is It is linked to the auxiliary clutch lever 24 via a link mechanism 115.

  In the above configuration, when the auxiliary clutch lever 24 is tilted, the clutch control lever 72 is pushed and pulled through the link mechanism 115 to rotate the lever shaft 73, and the outer peripheral surface of the rotating roller 183. The cam body 73a in contact with is rotated.

  At this time, as shown in FIGS. 16 (a) and 16 (b), as the cam body 73a rotates about the axis, the contact portion with the rotating roller 183 has an edge 73a2 having an acute cross section from the flat surface 73a1. The rotation roller 183 is pushed steplessly in the direction of an arrow 187 that presses the clutch friction member group 67. When the lever shaft 73 further rotates and the outer peripheral curved surface portion 73a3 of the cam body 73a comes into contact with the outer peripheral surface of the rotating roller 183, the rotating roller 183 is moved to an arrow 187 by the elastic force of the biasing spring 188. It is pushed steplessly in the opposite direction.

  In this way, the clutch fork 75 that moves integrally with the rotating roller 183 moves to the left as indicated by the arrow 187, and the clutch friction member group 67 is moved between the fork portion 75b of the clutch fork 75 and the left large-diameter gear. When pressed so as to be sandwiched between 57L and 57L, the auxiliary clutch mechanism 30 is set to a state capable of outputting transmission torque between the large-diameter gears 57L and 57R.

  At this time, the pressing amount of the clutch friction member group 67 by the fork portion 75b corresponds to the pressing amount of the rotating roller 183 by the cam body 73a, and the pressing amount corresponds to the outer peripheral surface of the rotating roller 183 and the cam body as described above. It can be increased or decreased steplessly by changing the contact site with 73a.

  Therefore, when the auxiliary clutch lever 24 is at the position 80 of the lever guide 24a shown in FIG. 11, the clutch control lever 72 is at the position 189 shown in FIG. The flat portion 73a1 is in contact in the vertical state shown in FIG. For this reason, the pushing amount of the rotating roller 183 is zero, the clutch friction member group 67 is not pressed at all by the fork portion 75b, and the auxiliary clutch mechanism 30 is interposed between the left and right large-diameter gears 57L and 57R. No torque is transmitted.

  Subsequently, when the auxiliary clutch lever 24 is moved to the position 81, the clutch control lever 72 is rotated to the position 190. On the outer peripheral surface of the rotating roller 183, the flat portion 73a1 of the cam body 73a is moved from the vertical state. The contact is made in a posture rotated in the direction of the arrow 89. For this reason, the pushing amount of the rotating roller 183 increases, the clutch friction member group 67 is pressed by the fork portion 75b, and the clutch friction members 77 and 78 are pressed against each other, so that the left and right large diameter gears 57L and 57R are in contact with each other. Are coupled with a low transmission torque.

  Further, when the auxiliary clutch lever 24 is moved to the position 82, the clutch control lever 72 is rotated to the position 191, and the edge 73a2 of the cam body 73a is formed on the outer peripheral surface of the rotating roller 183 as shown in FIG. ) Touch as shown. For this reason, the pushing amount of the rotating roller 183 further increases, the pushing amount of the clutch friction member group 67 is also increased by the fork portion 75b, and the clutch friction members 77 and 78 are pressed more strongly.

  As shown in FIGS. 3 and 11, the transmission torque setting operation tool 119 of the auxiliary clutch mechanism 30 includes a stepped pedal linked to the auxiliary clutch mechanism in addition to the manual auxiliary clutch lever 24. 116 is also provided, and the link mechanism is configured so that it can be changed to a high transmission torque higher than the transmission torque set by the auxiliary clutch lever 24 only when the pedal 116 is depressed. In this case, the clutch control lever 72 is rotated to the position 189a, and the cam body 73a is rotated in the direction of the arrow 89 as shown in FIG. 16 (b) or more, and the pushing amount of the rotating roller 183 is further increased. The members 77 and 78 are further pressed against each other.

A steering operation using the auxiliary clutch mechanism 30 having such a configuration will be described.
As shown in FIGS. 3, 11, and 14, during traveling in the dry field, the auxiliary clutch lever 24 is held at a position 80 in advance, and the transmission torque of the auxiliary clutch mechanism 30 is set to substantially zero. Thereby, it is possible to perform straight advance, slow turn, and sudden turn without the influence of the auxiliary clutch mechanism 30.

  When the wet paddle travels, the auxiliary clutch lever 24 is held in the position 81 in advance, and the auxiliary clutch mechanism 30 is set to a low transmission torque transmission state. Thus, in the straight traveling mode, the power transmission through the auxiliary clutch mechanism 30 does not occur because the both side clutches 65L and 65R are in the engaged state. In the slow turning mode, for example, when the left side clutch 65L is disengaged, a low transmission torque driving force is applied to the left traveling axle 46L inside the turning through the clutch friction member group 67. Even if the running resistance of the axle 46L is large, the running axle 46L is slightly rotated without stopping, and can turn slowly with a turning radius as intended by the operator.

  When traveling on a super wet field with even greater running resistance, the auxiliary clutch lever 24 is held in position 82 in advance, and the auxiliary clutch mechanism 30 is set to a high transmission torque transmission state. Thereby, in the slow turning mode, for example, when the left side clutch is disengaged, a greater driving force is applied to the left traveling axle 46L inside the turning, so that the traveling axle 46L is braked by the traveling resistance. Even in this case, the traveling axle 46L is strongly driven to rotate without stopping and can maintain a slow turning state.

  When the operator determines that the running resistance exceeds the transmission torque set by the auxiliary clutch lever 24 during such gentle turning, the pedal 116 is depressed to operate the auxiliary clutch mechanism 30. Temporarily further increase the transmission torque. As a result, the traveling axle 46L is driven to rotate more strongly without being stopped, and the slow turning state can be maintained.

  Note that the transmission torque of the auxiliary clutch mechanism 30 set by the auxiliary clutch lever 24 is set within a range in which the clutch friction member group 67 can slip in the sudden turning mode in which the side brakes 59L and 59R are applied. For this reason, the auxiliary clutch mechanism 30 does not hinder the sudden turning operation.

  That is, in the auxiliary clutch mechanism 30, the large-diameter gears 57L and 57R, which are left and right intermediate transmission members that transmit the driving force from the left and right side gears 56L and 56R, which are the output members, to the left and right traveling axles 46L and 46R. A plurality of clutch friction members 77 and 78 are connected to each other, and the clutch friction members 77 and 78 are stacked on each other to form a clutch friction member group 67. The clutch friction member group 67 is connected to a clutch fork 75 as a pressing member. Since it is possible to transmit any transmission torque between the large-diameter gears 57L and 57R by pressing, the clutch portion of the auxiliary clutch mechanism 30 can be constituted by a normal friction multi-plate type clutch friction member group, A complicated and large device is not required to reduce a part of the driving force to an arbitrary transmission torque, reducing component costs and maintenance. It can be achieved improvement, and the size of the housing according to the reduction of the installation space.

  Further, the torque changing operation device 68 includes a clutch fork 75 as the pressing member, a fork shaft 76 as a member support shaft that supports the base portion 75a of the clutch fork 75 and is horizontally mounted in the housing 35, Clutch friction is caused by rotation of the rotating roller 183, which is a roller-like member-side rotating body rotatably supported by the base portion 75a, and the rotation of the cam body 73a, which is a cam portion provided at one end, around the axis. Since the lever shaft 73 that pushes in the pressing direction of the member group 67 is provided, the front end of the clutch control lever, which is a lever member, is engaged with the notch recess formed in the base of the clutch fork as in the prior art. Compared to the case where the clutch fork is pushed in the direction of pressing the clutch friction member group, there is no worry of looseness due to parts accuracy and assembly accuracy. Friction due to contact between the latch control lever 72, the clutch fork 75 can also be reduced, thereby a significant improvement in the operation precision and operation efficiency.

Further, various configurations and other forms of lubrication, attachment, and arrangement in the auxiliary clutch mechanism 30 as described above will be described.
As shown in FIG. 14, the clutch friction member group 67 is interposed between the inner and outer double cylinder portions 62 including the left and right clutch case portions 57La and 57Ra as described above. The clutch case portion 57Ra includes a first series oil passage 83 that penetrates the gear boss portion 57Rb in the axial direction and communicates the oil pocket 88 in the clutch case portion 57Ra with the oil reservoir 144, and the clutch case portion 57Ra. A large number of second communication oil passages 84 penetrating inward and outward in the direction are formed. Instead of the first series of oil passages 83, left and right axial oil passages 85L and 85R are formed through the shaft centers of the left and right reduction shafts 45L and 45R, respectively. The oil pocket 88 may be communicated with the oil sump 144 through 85R.

  As a result, the oil in the oil reservoir 144 is introduced into the oil pocket 88 in the clutch case portion 57Ra through the first lubricating oil passage 86 including the first series oil passage 83 or the shaft center oil passages 85L and 85R. The clutch friction member group 67 can be supplied through the second lubricating oil passage 87 including the second communication oil passage 84.

  That is, the clutch is interposed between the inner and outer double cylindrical portions 62 formed by opposingly forming the clutch case portions 57La and 57Ra which are cylindrical portions having different diameters to the large diameter gears 57L and 57R which are the left and right intermediate transmission members. A first lubricating oil passage 86 for arranging the friction member group 67 and introducing the lubricating oil in the housing 35 into the clutch case portion 57Ra which is the inner cylindrical portion of the inner and outer double cylindrical portions 62, Since the second lubricating oil passage 87 for guiding the lubricating oil from the inside of the clutch case portion 57Ra to the clutch friction members 77 and 78 is provided, the clutch friction member group 67 which is between the inner and outer double cylindrical portions 62 and is difficult to lubricate, Lubricating oil can be supplied effectively, and the life of the clutch friction members 77 and 78 can be improved.

  Subsequently, with respect to the torque changing operation device 68, as shown in FIGS. 15 and 16, the base end portion 182a of the roller pin 182 penetrating from the base portion 75a of the clutch fork 75 to the fork shaft 76 has a cylindrical bearing. The rotating roller 183 is rotatably supported with respect to the base end portion 182a via the bearing 192. For example, a needle bearing or a dry bearing such as a DU bush can be used as the bearing 192.

  As a result, the frictional force between the outer peripheral surface 182a2 of the base end portion 182a of the roller pin 182 and the inner peripheral surface 183a of the boss portion of the rotating roller 183 can be reduced, and the rotational force of the lever shaft 73 can be reduced. Therefore, the clutch fork 75 can be smoothly pressed by the clutch fork 75 by efficiently converting the fork shaft 76 into a moving force in the axial direction.

  Further, as shown in FIG. 15, the roller pin 182 passes through the fork shaft 76 in the radial direction from the base portion 75a of the clutch fork 75, as described above, and the retaining ring 184 is externally fitted to the protruding end 182b. However, instead of this, as shown in FIG. 17, a roller pin 182A having a short shaft length may be used.

  The roller pin 182A has its tip fixed to the outer periphery of the base portion 75a by welding or the like, and the rotation roller 183 is rotatably supported on the outer periphery.

  This eliminates the need for the retaining ring 184 for positioning and fixing, and can reduce component costs and improve maintainability by reducing the number of components.

  In addition, as shown in FIG. 16, in the lever shaft 73, as described above, the substantially semi-cylindrical cam body 73a includes the flat surface portion 73a1, the edge portion 73a2 having an acute cross section, and the outer peripheral curved surface portion 73a3. However, instead of this, as shown in FIG. 18, a lever shaft 193 provided with a cam profile surface portion 193a2 may be used instead of the edge portion 73a2.

  The cam profile surface portion 193a2 has a smooth shape that is cut out in the shape of a cross section R toward the inside in the radial direction, and the flat surface portion 193a1 and the outer peripheral curved surface portion 193a3 are provided continuously with the cam profile surface portion 193a2 as a boundary. A cam body 193a is formed.

  When the lever shaft 193 is rotated, the rotation roller 183 is pushed by the cam profile surface portion 193a2 of the cam body 193a. From the rotation center 195 of the lever shaft 193 to an arbitrary contact portion on the cam profile surface portion 193a2. The distance 197 is shorter than the distance 196 in the substantially semi-cylindrical cam body 73a.

  Thereby, compared with the case of this cam body 73a, the operation force required for the rotation operation of the lever shaft 193 can be reduced, and the friction with the rotating roller 183 can be reduced.

  Furthermore, instead of the cam body 73a of the lever shaft 73 and the cam body 193a of the lever shaft 193, as shown in FIG. 19, a lever shaft 198 provided with a roller-like rotating roller portion 198c may be used.

  The lever shaft 198 is rotatably supported by a shaft main body 198a, a roller pin portion 198b protruding in the axial direction from a radially eccentric position on the shaft end surface 198a1 of the front end of the shaft main body 198a, and the roller pin portion 198b. And the rotating roller portion 198c.

  Then, when the lever shaft 198 is rotated, the rotation roller 183 is pushed by the outer peripheral surface 198c1 of the rotation roller portion 198c, but, as in the case of the lever shaft 193, from the rotation center 200 of the lever shaft 198, A distance 199 to an arbitrary contact portion on the outer peripheral surface 198c1 of the rotating roller portion 198c is shorter than a distance 196 in the cam body 73a having a substantially semi-cylindrical shape.

  Thereby, as compared with the case of the cam body 73a, the operation force required for the rotation operation of the lever shaft 198 can be reduced, and the friction with the rotating roller 183 can be reduced.

  The lever shafts 73, 193, 198 are fitted with cylindrical bearings 201 similarly to the roller pins 182, and the lever shafts 73, 193, 198 are attached to the housing 35 via the bearings 201. The boss is supported so as to be rotatable. Also, the bearing 201 can be a dry bearing such as the needle bearing or DU bush.

  Thereby, the frictional force between the outer peripheral surface of the lever shafts 73, 193, 198 and the inner peripheral surface of the boss portion of the housing 35 can be reduced, and the rotational force of the lever shafts 73, 193, 198 can be reduced. Therefore, the clutch fork 75 can be smoothly pressed by the clutch fork 75 by efficiently converting the fork shaft 76 into a moving force in the axial direction.

  Next, the arrangement of the on / off operation device 130 of the side clutch mechanism 33 and the torque change operation device 68 of the auxiliary clutch mechanism 30 configured as described above will be described with reference to FIGS. 11 and FIG.

  As described above, the on / off operation device 130 accommodates the pair of left and right steering cylinders 61L and 61R in the device case 131 fastened and fixed to the upper portion of the front surface of the housing 35 by a plurality of bolts 149, and the steering cylinder. A pair of left and right connecting arms 133L and 133R are connected to the piston rods 134L and 134R of 61L and 61R, respectively, and are arranged in the upper half of the front surface of the housing 35 as shown in FIG.

  On the other hand, the torque changing operation device 68 is provided with a clutch fork 75 supported by a fork shaft 76, and a clutch control lever 72 is connected to a lever shaft 73 that pushes a rotating roller 183 of the clutch fork 75 by a cam body 73a. As shown in FIG. 5, the housing 35 is disposed at a substantially central portion on the rear surface.

  As shown in FIGS. 6, 7, and 11, the on / off operation device 130 and the torque changing operation device 68 are opposed to each other at a position where the housing 35 is sandwiched and most of them overlap in a front view. Are arranged as follows.

  That is, the left and right side clutches 65L and 65R that connect and disconnect the power to the left and right traveling axles 46L and 46R, and the left and right side gears 56L and 56R that are output members from the left and right side clutches 65L and 65R are side-mounted. Left and right side brakes 59L and 59R that can be braked when the clutch is disengaged are provided, and a part of the driving force transmitted from the side gears 56L and 56R to one traveling axle between the left and right traveling axles 46L and 46R. In the axle drive device 2 of the combine 1 that is a work vehicle having a variable capacity auxiliary clutch mechanism 30 that can be transmitted to the other traveling axle by reducing the torque to an arbitrary transmission torque, the side clutches 65L and 65R, The on / off operation device 130 for turning on / off the side brakes 59L and 59R and the auxiliary clutch mechanism 30 are used to transmit torque. Further, the torque changing operation device 68 for performing the change is arranged separately on one side and the other side of the housing 35 of the axle drive device 2, in this embodiment, the front side and the rear side, so that the on / off operation device 130 is arranged. And the torque changing operation device 68 can be configured around the housing 35 without interference.

  The present invention includes left and right side clutches for connecting and disconnecting power to the left and right traveling axles, and left and right side brakes capable of braking each output member from the left and right side clutches when the side clutch is disengaged. It can be applied to an axle drive device of a crawler vehicle.

1 Combine (work vehicle)
2 Axle drive device 30 Auxiliary clutch mechanism 35 Housing 35a / 35b Brake case (brake case)
44 Side clutch shaft (support shaft)
46L / 46R Traveling axle 56L / 56R Side gear (output member)
56La ・ 56Ra Outer end cylinder (interlocking member)
57L / 57R large-diameter gear (intermediate transmission member)
57La Clutch case (outer cylinder)
57Ra Clutch case (inner cylinder)
59L / 59R Side brake 62 Inner / outer double cylinder part 65L / 65R Side clutch 67 Clutch friction member group 68 Torque change operation device 73/193/198 Lever shaft 73a / 193a Cam body (cam part)
75 Clutch fork (pressing member)
75a Base 76 Fork shaft (member support shaft)
77/78 Clutch friction member 86 First lubricating oil passage 87 Second lubricating oil passage 130 On / off operation device 176 Shaft center oil passage 177L / 177R Radius oil passage 180 Brake lubricating oil passage 183 Rotating roller (member side rotating body)

Claims (5)

  Left and right side clutches for connecting and disconnecting power to the left and right traveling axles, and left and right side brakes capable of braking each output member from the left and right side clutches when the side clutch is disengaged are provided. Between the axles, a variable capacity type auxiliary clutch mechanism capable of reducing a part of the driving force transmitted from the output member to one traveling axle to an arbitrary transmission torque and transmitting it to the other traveling axle. In the work vehicle axle drive device provided, the on / off operation device for turning on / off the side clutch and the side brake, and the torque change operation device for changing the transmission torque by the auxiliary clutch mechanism are: An axle drive device for a work vehicle, wherein the axle drive device is arranged separately on one side and the other side of the housing.   In the auxiliary clutch mechanism, a plurality of clutch friction members are connected to each of the left and right intermediate transmission members that transmit the driving force from the output members to the left and right traveling axles, and the clutch friction members are stacked on each other to provide clutch friction. 2. The axle drive device for a work vehicle according to claim 1, wherein a member group is formed, and an arbitrary transmission torque can be transmitted between the intermediate transmission members by pressing the clutch friction member group with a pressing member. .   The torque changing operation device is configured to support the pressing member, a base portion of the pressing member, and a member support shaft horizontally mounted in the housing, and a roller-shaped member side rotation that is rotatably supported by the base portion. The work vehicle according to claim 2, further comprising: a body, and a lever shaft that pushes the member-side rotating body in a direction of pressing the clutch friction member group by rotating around a shaft center of a cam portion provided at one end. Axle drive system.   The clutch friction member group is disposed between inner and outer double cylinder portions formed by opposingly forming cylindrical portions having different diameters to the left and right intermediate transmission members, and an inner cylinder of the inner and outer double cylinder portions. A first lubricating oil passage for introducing the lubricating oil in the housing into the inside of the portion, and a second lubricating oil passage for guiding the lubricating oil from the inside of the inner cylindrical portion to the clutch friction member. The axle drive device for a work vehicle according to claim 2 or 3.   The side brake is configured by engaging a plurality of side brake friction members with each of an interlocking member interlocked with the traveling axle and a brake case fixed to the housing, and rotatably supports the interlocking member. A brake lubricating oil passage having a shaft oil passage of the support shaft and a radial oil passage communicating with the shaft oil passage and opening on the surface of the support shaft is provided, and the housing is provided via the brake lubricant oil passage. The axle drive device for a work vehicle according to any one of claims 1 to 4, wherein the lubricating oil is supplied toward the side brake friction member.

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