WO2017065118A1 - Hydraulic transmission device - Google Patents

Abstract

Hydraulic servo mechanisms 205, 208 for actuating hydraulic continuously variable transmissions 64, 70 are arranged within a continuously variable transmission case 323 so as to be separated to either side of the hydraulic continuously variable transmissions 64, 70. In an oil path block 401 are formed closed-loop oil paths 201, 202 for the hydraulic continuously variable transmissions 64, 70, and a charge oil path 219 connecting the closed-loop oil paths 201, 202. Servo oil paths 402, 403 connecting the charge oil path 219 and the hydraulic servo mechanisms 205, 208 are formed from the oil path block 401 toward the continuously variable transmission case 323 so as to cross the charge oil path 219 at a right angle and extend parallel to each other.

Description

Hydraulic transmission

The present invention relates to a hydraulic transmission.

2. Description of the Related Art Conventionally, a work vehicle such as a combiner includes a continuously variable transmission case incorporating a pair of hydraulic continuously variable transmissions that are a combination of a hydraulic pump and a hydraulic motor, and an oil passage block attached to one side of the continuously variable transmission case It is common practice to install a hydraulic transmission. In this type of hydraulic transmission, a technique in which a hydraulic servo mechanism for operating each hydraulic continuously variable transmission is built in a continuously variable transmission case is already known (see, for example, Patent Document 1).

JP 2004-68974 A

However, in the prior art, the oil passage structure to each hydraulic servo mechanism in the continuously variable transmission case is complicated and long, for example, extending obliquely with respect to the plate thickness direction of the oil passage block. Therefore, there is a problem that it is difficult to form an oil passage for the continuously variable transmission case and the manufacturing cost increases.

The present invention has a technical problem of providing a hydraulic transmission that has been improved by examining the current situation as described above.

1st aspect of this invention is equipped with the continuously variable transmission case which incorporated the pair of the hydraulic continuously variable transmission which combined a hydraulic pump and a hydraulic motor, and the oil path block attached to one side of the said continuously variable transmission case. In the hydraulic transmission apparatus, the hydraulic servo mechanism for operating each of the hydraulic continuously variable transmissions is distributed and arranged on both sides of the both hydraulic continuously variable transmissions in the continuously variable transmission case. In the block, a closed loop oil passage for each of the hydraulic continuously variable transmissions and a charge oil passage connecting both the closed loop oil passages are formed, and a servo oil passage connecting the charge oil passage and each of the hydraulic servo mechanisms is formed. The oil passage block is formed toward the continuously variable transmission case so as to extend perpendicular to the charge oil passage and in parallel with each other.

According to a second aspect of the present invention, in the hydraulic transmission according to the first aspect, each closed loop oil passage is orthogonal to a bypass oil passage extending in parallel with the charge oil passage, and the closed loop oil passage and the charge A check valve is disposed at a position orthogonal to the oil passage, and a relief valve is disposed at a position orthogonal to each of the closed loop oil passage and the bypass oil passage.

According to a third aspect of the present invention, in the hydraulic transmission of the first or second aspect, a surplus relief valve that discharges surplus hydraulic oil in the charge oil passage is connected to one end side of the charge oil passage. It is that.

According to the present invention, a hydraulic type comprising a continuously variable transmission case incorporating a pair of hydraulic continuously variable transmissions that are a combination of a hydraulic pump and a hydraulic motor, and an oil passage block attached to one side of the continuously variable transmission case. In the transmission, a hydraulic servomechanism for operating each of the hydraulic continuously variable transmissions is arranged in the continuously variable transmission case so as to be distributed to both ends across the both hydraulic continuously variable transmissions. Forming a closed loop oil passage for each of the hydraulic continuously variable transmissions and a charge oil passage connecting both the closed loop oil passages, and connecting the charge oil passage and each of the hydraulic servo mechanisms with the charge oil passage. Since the oil passage block is formed from the oil passage block toward the continuously variable transmission case so as to be orthogonal to the oil passage and parallel to each other, servo oil passages for the respective hydraulic servo mechanisms are provided. Wherein the continuously variable transmission case along a side of each hydraulic servo mechanism closer can be formed by and reduced as much as possible into linearly. Therefore, the servo oil passages can be easily formed in the continuously variable transmission case or the oil passage block, the workability is good, and the manufacturing can be performed at low cost.

In particular, according to the second aspect of the present invention, since the check valve and the relief valve are separately arranged for each closed loop oil passage, an expensive check relief valve (having both a check function and a relief function) is provided. This also contributes to the cost reduction of the hydraulic transmission.

It is a left view of the combine which mounts the vehicle drive device of this invention. It is a right view of a combine. It is a top view of a combine. It is the perspective view which looked at the traveling machine body front part from the diagonally left front. It is a drive system diagram of a combine. It is a drive system figure of the drive device for vehicles. It is a hydraulic circuit diagram of a hydraulic continuously variable transmission. It is the perspective view which looked at the cab and the vehicle drive device from diagonally left front. It is a right view of the drive device for vehicles. It is a left view of the vehicle drive device. It is a left side sectional view of a mission case showing a gear arrangement relation. It is an expanded sectional view of the straight output in a mission case. It is an expanded sectional view of turning output in a mission case. It is a back sectional view of an auxiliary transmission gear mechanism. It is a back sectional view of a PTO boss part. It is a rear surface sectional view of another example in which a PTO shaft is attached to a PTO boss part. It is a back sectional view of a turning brake. It is a left view of the vehicle drive device which shows another example of a lubrication structure. It is sectional drawing of the axle front end side. It is sectional drawing of an oil path block. It is sectional drawing of a hydraulic transmission (a continuously variable transmission case and an oil path block). FIG. 2 is a partial cross-sectional view of a hydraulic transmission (a continuously variable transmission case and an oil passage block), in which (a) is a partial cross-sectional view of a side surface, and (b) is a combined cross-sectional view with a plane cross-section.

Hereinafter, an embodiment embodying the present invention will be described based on a drawing of a vehicle drive device mounted on a normal combine. First, the schematic structure of the combine will be described with reference to FIGS. In the following description, the left side in the forward direction of the traveling machine body 1 is simply referred to as the left side, and the right side in the forward direction is also simply referred to as the right side.

As shown in FIGS. 1 to 3, a normal combine as a work vehicle includes a traveling machine body 1 supported by a pair of left and right crawler belts 2 made of rubber crawlers as a traveling portion. At the front part of the traveling machine body 1, a harvesting unit 3 for harvesting uncut rice grains such as rice, wheat, soybeans or corn while being harvested is mounted by a single-acting lifting hydraulic cylinder 4 so as to be adjustable up and down. .

On the left side of the traveling machine 1, a threshing unit 9 for threshing the harvested cereal meal supplied from the harvesting unit 3 is mounted. In the lower part of the threshing unit 9, a grain sorting mechanism 10 for performing swing sorting and wind sorting is arranged. A driver's cab 5 on which an operator is boarded is mounted on the front right side of the traveling machine body 1. An engine 7 as a power source is disposed on the cab 5 (below the driver seat 42). Behind the cab 5 (on the right side of the traveling machine body 1), a grain tank 6 for taking the grain from the threshing unit 9 and a grain for discharging the grain in the grain tank 6 toward the truck bed (or container, etc.) A discharge conveyor 8 is arranged. The grain discharge conveyor 8 is tilted toward the outside of the machine so that the grains in the grain tank 6 are carried out by the grain discharge conveyor 8.

The mowing unit 3 includes a feeder house 11 that communicates with the handling port 9a of the front part of the threshing unit 9 and a horizontally long bucket-shaped grain header 12 that is provided continuously at the front end of the feeder house 11. A scraping auger 13 (platform auger) is rotatably supported in the grain header 12. A take-up reel 14 with a tine bar is disposed above the front portion of the take-up auger 13. A clipper-shaped first cutting blade 15 is disposed in front of the grain header 12. Left and right weed bodies 16 are provided to project from the left and right sides of the front part of the grain header 12. In addition, a supply conveyor 17 is installed in the feeder house 11. A cutting port 9a positioned at the feed end side of the supply conveyor 17 is provided with a cutting grain input beater 18 (front rotor). The lower surface portion of the feeder house 11 and the front end portion of the traveling machine body 1 are connected via an elevating hydraulic cylinder 4, and the mowing unit 3 uses an elevating fulcrum as a mowing input shaft 89 (feeder house conveyor shaft) described later. The cylinder 4 moves up and down.

With the above configuration, the tip side of the uncut grain culm between the left and right weed bodies 16 is scraped by the scraping reel 14, and the base side of the uncut grain culm is cut by the first cutting blade 15. By the rotational drive of 13, the harvested cereal grains are collected near the entrance of the feeder house 11 near the center of the grain header 12 in the lateral width. The whole amount of the harvested cereal meal of the grain header 12 is conveyed by the supply conveyor 17 and is configured to be input to the handling port 9 a of the threshing unit 9 by the beater 18. The grain header 12 is provided with a horizontal control hydraulic cylinder (not shown) that rotates about the horizontal control fulcrum shaft, and the grain header 12 is adjusted by the horizontal control hydraulic cylinder to adjust the horizontal inclination of the grain header 12. 12 and the first cutting blade 15 and the take-up reel 14 can be supported horizontally with respect to the field scene.

As shown in FIGS. 1 and 3, a handling cylinder 21 is rotatably provided in a handling chamber of the threshing unit 9. A handling cylinder 21 is pivotally supported on a handling cylinder shaft 20 extended in the front-rear direction of the traveling machine body 1. On the lower side of the handling cylinder 21, a receiving net 24 for allowing the grains to leak is stretched. In addition, a spiral screw blade-shaped intake blade 25 projects outward in the radial direction on the outer peripheral surface of the front portion of the handling cylinder 21.

With the above-described configuration, the harvested cereal straw introduced from the handling port 9 a by the beater 18 is conveyed toward the rear of the traveling machine body 1 by the rotation of the handling cylinder 21, and between the handling cylinder 21 and the receiving net 24. Kneaded and threshed. The threshing of grains or the like smaller than the mesh of the receiving net 24 leaks from the receiving net 24. The sawdust and the like that do not leak from the receiving net 24 are discharged from the dust outlet 23 at the rear of the threshing portion 9 to the field by the conveying action of the handling cylinder 21. A plurality of dust feed valves (not shown) for adjusting the conveying speed of shed grains in the handling chamber are pivotally mounted on the upper side of the handling cylinder 21 so as to be rotatable. By adjusting the angle of the dust feed valve, the conveying speed (residence time) of threshing in the handling chamber can be adjusted according to the variety and properties of the harvested cereal.

On the other hand, the grain sorting mechanism 10 disposed below the threshing unit 9 includes a rocking sorter 26 for specific gravity sorting having Glen bread, chaff sheave, Glen sheave, Strollac, and the like. Further, as the grain sorting mechanism 10, a blower fan-shaped tongue 29 for supplying sorting wind to the swing sorting board 26 is provided. The threshing that has been threshed by the handling cylinder 21 and leaked from the receiving net 24 is caused by the specific gravity sorting action of the swing sorter 26 and the wind sorting action of the blower fan-shaped tang 29, so And the like), the mixture of grain and straw (second thing such as grain with branches), and sawdust and the like.

The first conveyor mechanism 30 and the second conveyor mechanism 31 are provided on the lower side of the swing sorter 26 as the grain sorting mechanism 10. The grain (first thing) dropped from the swing sorter 26 by sorting the swing sorter 26 and the blower fan-shaped tongue 29 is collected in the glen tank 6 by the first conveyor mechanism 30 and the cereal conveyor 32. . The mixture of grains and straw (second product) is returned to the sorting start end side of the swing sorting plate 26 through the second conveyor mechanism 31 and the second reduction conveyor 33 and is re-sorted by the swing sorting plate 26. The The sawdust and the like are configured to be discharged from the dust outlet 23 at the rear of the traveling machine body 1 to the field.

Further, as shown in FIGS. 1 to 4, the cab 5 is provided with a control column 41 and a driver seat 42 on which an operator sits. The steering column 41 includes an accelerator lever 40 that adjusts the rotational speed of the engine 5, a round steering handle 43 that changes the course of the traveling machine body 1 by a rotation operation by an operator, and a main body that switches the moving speed of the traveling machine body 1. A shift lever 44 and a sub-shift lever 45, a cutting clutch lever 46 for driving or stopping the cutting unit 3, and a threshing clutch lever 47 for driving or stopping the threshing unit 9 are arranged. A sunshade roof body 49 is attached to the front upper surface side of the Glen tank 6 via a sun visor support 48, and the sunshade roof body 49 covers the upper side of the cab 5.

1 and 2, left and right track frames 50 are arranged on the lower surface side of the traveling machine body 1. The track frame 50 includes a drive sprocket 51 that transmits the power of the engine 7 to the crawler belt 2, a tension roller 52 that maintains the tension of the crawler belt 2, a plurality of track rollers 53 that hold the ground side of the crawler belt 2 in a grounded state, An intermediate roller 54 that holds the non-grounding side of the crawler belt 2 is provided. The front side of the crawler belt 2 is supported by the drive sprocket 51, the rear side of the crawler belt 2 is supported by the tension roller 52, the ground side of the crawler belt 2 is supported by the track roller 53, and the non-ground side of the crawler belt 2 is supported by the intermediate roller 54 I am letting.

Next, the drive structure of the combine will be described with reference to FIGS. As shown in FIGS. 4 to 6, the transmission case 63 is provided with a linear hydraulic continuously variable transmission 64 for traveling speed change having a linear pump 64a and a linear motor 64b. The engine 7 is mounted on the upper right side of the front part of the traveling machine body 1, and a mission case 63 is disposed on the front part of the traveling machine body 1 and on the left side of the engine 7. An output shaft 65 protruding leftward from the engine 7 and a mission input shaft 66 protruding leftward from the mission case 63 are connected by an engine output belt 67 so that power can be transmitted. In addition, the working unit charge pump 68 and the cooling fan 69 that drive the lifting hydraulic cylinder 4 and the like are arranged in the engine 7, and the working unit charge pump 68 and the cooling fan 69 are driven by the engine 7.

Further, a turning hydraulic continuously variable transmission 70 for steering having a turning pump 70 a and a turning motor 70 b is provided in the mission case 63, and a straight hydraulic continuously variable transmission 64 and a turning hydraulic continuously variable transmission 70 are connected via a mission input shaft 66. While the output of the engine 7 is transmitted to the vehicle, the steering handle 43 and the main and auxiliary transmission levers 44 and 45 control the output of the straight hydraulic continuously variable transmission 64 and the swing hydraulic continuously variable transmission 70, so that the straight hydraulic continuously variable transmission is achieved. The left and right crawler belts 2 are driven through the machine 64 and the turning hydraulic continuously variable transmission 70 to travel and move in the field. In the embodiment, straight and turning hydraulic continuously variable transmissions 64 and 70 are arranged on the upper right side of the mission case 63. The straight and turning hydraulic continuously variable transmissions 64 and 70 and the transmission case 63 constitute the vehicle drive device of the present invention.

As shown in FIGS. 4 and 5, on the front side of the threshing portion 9, a handling cylinder drive case 71 that pivotally supports the front end side of the handling cylinder shaft 20 is disposed. Then, a horizontally long handling cylinder input shaft 72 for driving the handling cylinder 21 is pivotally supported on the handling cylinder drive case 71. Moreover, the counter shaft 73 penetrated in the right and left of the threshing part 9 is provided. A counter shaft 73 extending from the left and right sides of the threshing portion 9 to the left and right sides is provided so as to penetrate the threshing portion 9 in the left-right direction through the lower side of the handling cylinder 21. A working unit input pulley 83 is provided at the right end of the counter shaft 73. The right end portion of the counter shaft 73 is connected to the output shaft 65 of the engine 7 through a tension pulley type threshing clutch 84 and a working unit drive belt 85 so as to be able to transmit power.

Above the counter shaft 73 and in front of the handling cylinder 21, a handling cylinder input shaft 72 extending in the lateral direction of the traveling machine body 1, a beater 18 arranged in the lateral direction of the traveling machine body 1, and a lateral direction of the traveling machine body 1 An extended cutting input shaft 89 is provided. In addition, the cylinder input mechanism 90 that transmits the driving force of the counter shaft 73 to the cylinder input shaft 72 includes cylinder driving pulleys 86 and 87 and a cylinder driving belt 88, and the driving force from the engine 7 is transmitted. A cylinder input mechanism 90 ( cylinder driving pulleys 86 and 87 and a cylinder driving belt 88) is disposed at one end of the counter shaft 73 on the engine 7 side. Further, the cutting input mechanism 100 that transmits the driving force of the counter shaft 73 to the cutting input shaft 89 includes cutting drive pulleys 106 and 107 and a cutting drive belt 114, and one end portion on the engine 7 side where the barrel input mechanism 90 is disposed. The mowing input mechanism 100 (the mowing driving pulleys 106 and 107 and the mowing driving belt 114) is disposed at the other end of the counter shaft 73 on the opposite side.

Further, as shown in FIG. 4, a cutting support frame 36 is installed in front of the threshing portion 9 on the upper surface side of the traveling machine body 1. A cutting input shaft 89 is pivotally supported on the front side of the cutting support frame body 36 via a cutting bearing body in the left-right direction, and the beater shaft 82 is connected to the beater shaft 82 via a beater shaft 82. 18 is pivotally supported. Further, the forward / reverse switching case 121 is attached to the left outer surface of the cutting support frame 36, and the barrel driving case 71 is attached to the upper surface side of the cutting support frame 36.

On the other hand, a left-right cutting input shaft 89 for driving the supply conveyor 17 in the feeder house 11 is provided. The cutting drive force transmitted from the engine 7 to one end of the counter shaft 73 on the engine 7 side is transferred from the other end of the counter shaft 73 opposite to the engine 7 to the forward / reverse transmission shaft 122 of the cutting forward / reverse switching case 121. To communicate. The beater shaft 82 is driven via the forward bevel gear 124 or the reverse bevel gear 125 of the cutting forward / reverse switching case 121. Further, the cutting drive force is transmitted to the cutting input shaft 89 from the beater shaft 82 on which the beater 18 is pivotally supported.

That is, as shown in FIG. 5, the beater 18 is pivotally supported on the beater shaft 82 facing left and right, and the driving force of the engine 7 is transmitted from the one end portion of the beater shaft 82 to the cutting unit 3. The cutting forward / reverse rotation switching case 121 is disposed at the other left and right ends opposite to the engine 7 in 82, and the cutting forward / reverse rotation switching case 121 is connected to the cutting forward / reverse rotation switching case 121 from the other end of the counter shaft 73 opposite to the engine 7. 7 driving force is transmitted.

Further, as shown in FIG. 5, a handling cylinder input shaft 72 facing left and right is provided on the front side of the threshing section 9, and the driving force transmitted from the engine 7 to one end of the counter shaft 73 on the engine 7 side is transmitted to the handling cylinder input shaft 72. A handling cylinder that is transmitted to one end of the engine 7 side, is provided with a handling cylinder input shaft 72 on the front side of the threshing part 9, the handling cylinder input shaft 72 is arranged in the lateral direction of the traveling machine body 1, and is arranged in the longitudinal direction of the traveling machine body 1 The handle cylinder 21 is pivotally supported on the shaft 20, and the front end side of the handle cylinder shaft 20 is connected to the left and right other end portions of the handle cylinder input shaft 72 opposite to the engine 7 via the bevel gear mechanism 75, and the counter shaft 73. The driving force of the engine 7 is transmitted from the left and right other ends opposite to the engine 7 to the grain sorting mechanism 10 that sorts the grain after threshing and the cutting part 3.

The right end of the cylinder input shaft 72 is connected to the right end of the counter shaft 73 on the side close to the engine 7 via the cylinder driving pulleys 86 and 87 and the cylinder driving belt 88. A front end side of the handling cylinder shaft 20 is connected to a left end portion of the handling cylinder input shaft 72 extending in the left-right direction via a bevel gear mechanism 75. The power of the engine 7 is transmitted from the right end portion of the counter shaft 73 to the front end side of the barrel shaft 20 via the barrel input shaft 72, and the barrel 21 is rotationally driven in one direction. On the other hand, the left end of the counter shaft 73 on the side away from the engine 7 is connected to the left end of the hot shaft 76 on which the blower fan-shaped hot spring 29 is supported via the hot drive pulleys 101 and 102 and the hot drive belt 103. The parts are connected. The power of the engine 7 is transmitted from the left end portion of the counter shaft 73 to the left end portion of the tang shaft 76, and the tang 29 is rotated in one direction.

Furthermore, the left end of the Karatsu shaft 76 is connected to the left end of the first conveyor shaft 77 of the first conveyor mechanism 30 and the left end of the second conveyor shaft 78 of the second conveyor mechanism 31 via the conveyor drive belt 111. The parts are connected. The left end portion of the second conveyor shaft 78 is connected to the left end portion of the crank-shaped swing drive shaft 79 pivotally supported by the rear portion of the swing sorting plate 26 via the swing sorting belt 112. Accordingly, the threshing clutch 84 is controlled to be turned on and off by the operation of the threshing clutch lever 47 by the operator, and each part of the grain sorting mechanism 10 and the handling cylinder 21 are driven by the turning on operation of the threshing clutch 84.

Note that the cereal conveyor 32 is driven via the first conveyor shaft 77, and the first selected grain of the first conveyor mechanism 30 is collected in the Glen tank 6. The second reduction conveyor 33 is driven via the second conveyor shaft 78, and the second selected grain (second product) mixed with the sawdust from the second conveyor mechanism 31 is moved to the upper side of the swing sorter 26. Returned to Further, in a structure in which a dust spreader spreader (not shown) is provided in the dust outlet 23, the left end portion of the Karatsu shaft 76 is connected to the spreader via the spreader drive pulley 104 and the spreader drive belt 105.

On the other hand, a beater shaft 82 that pivotally supports the beater 18 is provided. A forward / reverse switching case 121 is arranged at the left end of the beater shaft 82 on the side away from the engine 7. A forward / reverse transmission shaft 122 and a forward / reverse switching shaft 123 are provided in the forward / reverse switching case 121 while the left end of the beater shaft 82 is inserted into the forward / reverse switching case 121. The beater shaft 82 and the forward / reverse transmission shaft 122 are arranged on substantially the same axis. The left end portion of the forward / reverse transmission shaft 122 is connected to the left end portion of the counter shaft 73 via the mowing drive pulleys 106 and 107, the mowing drive belt 114, and the mowing clutch 115 (tension pulley).

As shown in FIG. 5, a cutting input shaft 89 is provided as a conveyor input shaft that pivotally supports the feed end side of the supply conveyor 17. A header drive shaft 91 is rotatably supported on the right side rear side of the grain header 12. Via the cutting drive chain 116 and the sprockets 117 to 119, the right end of the beater shaft 82 and the right end of the cutting input shaft 89 can be transmitted to the left end of the header drive shaft 91 extending in the left-right direction. Connect to A scraping shaft 93 that pivotally supports the scraping auger 13 is provided. An intermediate portion of the header drive shaft 91 is connected to the right end portion of the drive shaft 93 via a drive drive chain 92.

Also provided is a reel shaft 94 that pivotally supports the take-up reel 14. The intermediate portion of the header drive shaft 91 is connected to the right end portion of the reel shaft 94 via an intermediate shaft 95 and reel drive chains 96 and 97. The first cutting blade 15 is connected to the right end portion of the header drive shaft 91 via a first cutting blade drive crank mechanism 98. The feed conveyor 17, the auger 13, the take-up reel 14 and the first cutting blade 15 are driven and controlled by the turning-on / off operation of the cutting clutch 115 so that the tip side of the uncut grain culm in the field is continuously cut. It is composed.

As shown in FIG. 5, the forward rotation bevel gear 124 integrally formed with the forward / reverse transmission shaft 122, the reverse rotation bevel gear 125 rotatably supported on the cutting input shaft 89, and the reverse rotation bevel gear 125 are connected to the forward rotation bevel gear 124. An intermediate bevel gear 126 is installed in the forward / reverse switching case 121. The intermediate bevel gear 126 is always meshed with the forward bevel gear 124 and the reverse bevel gear 125. On the other hand, a slider 127 is slidably supported on the beater shaft 82 by a spline engagement shaft. The slider 127 is configured to be detachably engageable with the forward rotation bevel gear 124 via the claw clutch-shaped forward rotation clutch 128, and the slider 127 is engaged with the reverse rotation bevel gear 125 via the claw clutch-shaped reverse rotation clutch 129. It is configured to be detachably engageable.

In addition, a forward / reverse switching shaft 123 for sliding the slider 127 is provided, and a forward / reverse switching arm 130 is provided on the forward / reverse switching shaft 123, and the forward / reverse switching arm 130 is operated by operating a forward / reverse switching lever (forward / reverse operation tool). The forward / reverse switching shaft 123 is swung to rotate, the slider 127 is brought into and out of contact with the forward rotation bevel gear 124 or the reverse rotation bevel gear 125, and the forward rotation bevel gear 124 or reverse rotation via the forward rotation clutch 128 or the reverse rotation clutch 129. The slider 127 is selectively locked to the bevel gear 125, and the cutting input shaft 89 is connected to the forward / reverse transmission shaft 122 in the forward or reverse direction.

As shown in FIG. 5, the right end of the auger drive shaft 58 is connected to the output shaft 65 of the engine 7 via a tension pulley type auger clutch 56 and an auger drive belt 57. The front end side of the lateral feed auger 60 at the bottom of the Glen tank 6 is connected to the left end portion of the auger drive shaft 58 via a bevel gear mechanism 59. A vertical feed auger 62 of the grain discharge conveyor 8 is connected to the rear end side of the horizontal feed auger 60 via a bevel gear mechanism 61. Moreover, the grain discharge lever 55 which turns on and off the auger clutch 56 is provided. A grain discharge lever 55 is attached to the front surface of the Glen tank 6 behind the driver seat 42 so that the operator can operate the grain discharge lever 55 from the driver seat 42 side.

1, 2, and 4, a clipper-shaped second cutting blade 133 having substantially the same length as the first clipper-shaped cutting blade 15 is provided. As a second cutting blade frame for mounting the second cutting blade 133 on the traveling machine body 1, a left frame 134, a right frame 135, and a central frame 136 are provided. A second cutting blade base 137 is fixed to the leading end side of the left frame 134, the right frame 135, and the center frame 136, thereby constituting a second cutting blade mechanism 132.

Left and right grounding housings 138 are provided at both ends of the second cutting blade base 137. The 2nd cutting blade 133 is attached between the left and right grounding housings 138 of the 2nd cutting blade base 137 so that reciprocation is possible. On the other hand, the base end side of the right frame 135 is rotatably supported on the cab frame of the traveling machine body 1. Further, the base end side of the central frame 136 is rotatably supported on the front frame of the traveling machine body 1.

As shown in FIG. 5, a second cutting blade drive mechanism 171 that transmits a driving force from the forward / reverse switching case 121 to the second cutting blade 133 is provided. The second cutting blade drive mechanism 171 includes a second cutting blade drive shaft 172 that transmits a driving force to the second cutting blade 133, and an eccentric rotation shaft 174 that is connected to the second cutting blade drive shaft 172 via the bevel gear mechanism 173. The second cutting blade drive crank mechanism 175 is connected to the eccentric rotation shaft 174. One end side of the second cutting blade drive shaft 172 is inserted into the forward / reverse switching case 121, the intermediate bevel gear 126 is engaged with the second cutting blade drive shaft 172, and forward / reverse transmission is transmitted via the intermediate bevel gear 126. A second cutting blade drive shaft 172 is connected to the shaft 122.

The second blade driving crank mechanism 175 includes an eccentric rotating body 177 provided on the eccentric rotating shaft 174, a swing rotating shaft 178 connected to the eccentric rotating body 177, and a swing driving arm 179 connected to the swing rotating shaft 178. The push-pull rod 180 that connects the second cutting blade 133 to the swing drive arm 179 is provided. Instead of the second cutting blade drive shaft 172 and the bevel gear mechanism 173, a pair of sprockets and a transmission chain for connecting the eccentric rotation shaft 174 to the forward / reverse transmission shaft 122 are provided, and forward / reverse rotation is performed via the sprocket and the transmission chain. The second cutting blade 133 driving force may be transmitted from the transmission shaft 122 to the second cutting blade driving crank mechanism 175.

With the above configuration, the one-way rotation of the eccentric rotation shaft 174 is converted into the swing rotation of the swing rotation shaft 178 (reciprocating rotation that rotates forward and backward within a certain range), and the swing drive arm 179 is swung. The second cutting blade 133 is slid back and forth through the push-pull rod 180, and the residue (the side of the culm stock) immediately after being cut by the first cutting blade 15 is removed by the second cutting blade 133. It is configured to cut and reduce the height of the stock that remains in the field.

Also, as shown in FIG. 4, a cylindrical transmission frame 181 having a second cutting blade drive shaft 172 and a square box-shaped bevel gear case 182 having a bevel gear mechanism 173 are provided. One end side of the transmission frame 181 is detachably fastened to the forward / reverse switching case 121, and a bevel gear case 182 is detachably fastened to the other end side of the transmission frame 181. That is, the left frame 134 is supported on the forward / reverse switching case 121 via the eccentric rotating shaft 174, the bevel gear case 182, and the transmission frame 181. The second blade driving crank mechanism 175 is disposed in a second blade driving cover 185 that is detachably supported by the left frame 134 (see FIGS. 1 and 3).

With the above configuration, the cutting unit 3 is driven by the operation of engaging the cutting clutch 115, whereby the second cutting blade 133 is operated together with the first cutting blade 15, and the tip of the uncut grain culm in the field by the first cutting blade 15. The side is cut off, the tip side of the grain pod is brought into the threshing unit 9 from the feeder house 11, and the grain is taken out from the grain sorting mechanism 10 to the grain tank 6. On the other hand, the stumps (residues) remaining on the traces of the cereal crops harvested by the first cutting blade 15 are appropriately cut at the height by the second cutting blades 133, and the stumps remaining on the field after the harvesting work (stock sources) ) Are aligned to a substantially constant height. By reducing the height of the stump remaining in the field after the harvesting work, the post-treatment workability (cultivation workability, etc.) of the field can be improved.

Next, a power transmission structure such as the mission case 63 will be described with reference to FIGS. As shown in FIG. 6, a transmission hydraulic continuously variable transmission 64 having a linear pump 64a and a linear motor 64b and a steering hydraulic hydraulic continuously variable transmission for steering having a rotational pump 70a and a rotational motor 70b in a transmission case 63. A machine 70 is provided. The transmission input shaft 66 of the transmission case 63 is connected to the pump shaft 258 of the rectilinear pump 64a and the pump shaft 259 of the swing pump 70a, respectively, and is driven by gear connection. An engine output belt 67 is wound around a mission input pulley 169 provided on the projecting end side of the mission input shaft 66 outside the mission case 63. The output of the engine 7 is transmitted to the mission input pulley 169 via the engine output belt 67, and the linear pump 64a and the swing pump 70a are driven.

As shown in FIG. 6, the driving force output from the output shaft 65 of the engine 7 is applied to the pump shaft 258 of the linear pump 64a and the pump shaft 259 of the swing pump 70a via the engine output belt 67 and the mission input shaft 66, respectively. Communicated. In the rectilinear hydraulic continuously variable transmission 64, hydraulic oil is appropriately sent from the rectilinear pump 64a to the rectilinear motor 64b by the power transmitted to the pump shaft 258. Similarly, in the swing hydraulic continuously variable transmission 70, hydraulic oil is appropriately sent from the swing pump 70a to the swing motor 70b by the power transmitted to the pump shaft 259. Note that a transmission charge pump 151 that supplies hydraulic oil to the linear pump 64a, the linear motor 64b, the rotary pump 70a, and the rotary motor 70b is attached to the pump shaft 259 of the rotary pump 70a.

The rectilinear hydraulic continuously variable transmission 64 moves straight by changing and adjusting the tilt angle of the rotary swash plate in the rectilinear pump 64a in accordance with the amount of rotation of the main transmission lever 44 and the steering handle 43 disposed in the steering column 41. The discharge direction and discharge amount of the hydraulic oil to the motor 64b are changed. As a result, the rotation direction and the number of rotations of the rectilinear motor shaft 260 protruding from the rectilinear motor 64b are arbitrarily adjusted.

As shown in FIG. 6, the rotational power of the linear motor shaft 260 is transmitted from the linear transmission gear mechanism 250 to the auxiliary transmission gear mechanism 251. The auxiliary transmission gear mechanism 251 includes an auxiliary transmission low speed gear 254, an auxiliary transmission intermediate speed gear 255, and an auxiliary transmission high speed gear 256 that are switched by auxiliary transmission shifters 252 and 253 that are linked to each other. The low speed sub-shift shifter 252 is pivotally supported on a parking brake shaft 265 (sub-transmission output shaft) located on the output side of the sub transmission gear mechanism 251. The high-speed auxiliary transmission shifter 253 is pivotally supported on an auxiliary transmission countershaft 270 that constitutes the linear transmission gear mechanism 250. By operating the sub-shift lever 45 disposed in the control column 41, the output rotational speed of the linear motor shaft 260 is selectively switched to three speed stages, low speed, medium speed, and high speed. In the embodiment, a neutral position (a position at which the output of the sub shift becomes zero) is provided between the low speed and the medium speed of the sub shift.

As shown in FIG. 6, the parking brake shaft 265 (sub-transmission output shaft) is provided with a drum-type parking brake 266. The rotational power from the auxiliary transmission gear mechanism 251 is transmitted from the auxiliary transmission output gear 267 fixed to the parking brake shaft 265 to the left and right differential mechanisms 257. Each of the left and right differential mechanisms 257 includes a planetary gear mechanism 268. A straight traveling pulsar 292 is provided on the parking brake shaft 265. A rectilinear vehicle speed sensor 293 (see FIG. 9) is disposed opposite to the outer peripheral side of the rectilinear pulser 292. The rectilinear vehicle speed sensor 293 detects the rotational speed of the rectilinear output (also referred to as the rectilinear vehicle speed and the shift output of the auxiliary transmission output gear 267).

As shown in FIG. 6, each of the left and right planetary gear mechanisms 268 includes one sun gear 271 that meshes with the auxiliary transmission output gear 267, a plurality of planet gears 272 that mesh with the sun gear 271, a ring gear 273 that meshes with the planet gear 272, and a plurality of planets. And a carrier 274 in which a gear 272 is rotatably arranged on the same circumference. The left and right carriers 274 are located opposite to each other with an appropriate space on the same axis (on the sun gear shaft 275 and the left and right forced differential output shafts 277 described later). The left and right sun gears 271 are fixed to both ends of the sun gear shaft 275 in the axial direction. A center gear 276 is fixed to an intermediate portion in the axial direction of the sun gear shaft 275.

The left and right ring gears 273 are arranged concentrically with the sun gear shaft 275 in a state where the inner teeth of the inner peripheral surface mesh with the plurality of planetary gears 272. The external teeth on the outer peripheral surface of each ring gear 273 are connected to the steering output shaft 285 via intermediate gears 287 and 288 for left and right turning output described later. Each ring gear 273 is rotatably fitted to the left and right forced differential output shafts 277 projecting left and right outward from the outer surface of the carrier 274. The left and right axles 278 are connected to the left and right forced differential output shafts 277 via final gears 278a and 278b. Drive sprockets 51 are attached to the left and right axles 278. Accordingly, the rotational power transmitted from the auxiliary transmission gear mechanism 251 to the left and right planetary gear mechanisms 268 is transmitted from the left and right axles 278 to the drive sprockets 51 at the same rotational speed in the same direction, and the left and right crawler belts 2 are transmitted in the same direction. Driven at the same number of revolutions, the traveling machine body 1 moves straight (forward, backward).

The swing hydraulic continuously variable transmission 70 changes the tilt angle of the rotary swash plate in the swing pump 70a in accordance with the amount of rotation of the main transmission lever 44 and the steering handle 43 disposed in the control column 41, thereby turning. The discharge direction and discharge amount of the hydraulic oil to the motor 70b are changed. As a result, the rotation direction and the number of rotations of the swing motor shaft 261 protruding from the swing motor 70b are arbitrarily adjusted. A turning pulser 294 is provided on the steering counter shaft 280 (details will be described later). A turning vehicle speed sensor 295 (see FIG. 9) is disposed opposite to the outer peripheral side of the turning pulser 294. The turning vehicle speed sensor 295 detects the rotation speed of the turning output (also referred to as turning vehicle speed).

As shown in FIG. 6, in the transmission case 63, a wet multi-plate slewing brake 279 (steering brake) provided on the slewing motor shaft 261 (steering input shaft), and an upstream reduction gear on the slewing motor shaft 261. Steering counter shaft 280 connected through 281, steering output shaft 285 connected to steering counter shaft 280 through downstream reduction gear 286, and steering output shaft 285 through reverse gear 284 to left ring gear 273. And a right input gear mechanism 283 in which a steering output shaft 285 is connected to the right ring gear 273.

Rotational power of the turning motor shaft 261 is transmitted to the steering counter shaft 280 via the upstream reduction gear 281. The rotational power transmitted to the steering counter shaft 280 is transmitted to the left ring gear 273 as reverse rotational power via the left intermediate gear 287 and the reverse gear 284 of the left input gear mechanism 282, while the right input gear mechanism 283 It is transmitted to the right ring gear 273 as forward rotation power via the right intermediate gear 288.

When the auxiliary transmission gear mechanism 251 is neutral, power transmission from the straight-ahead motor 64b to the left and right planetary gear mechanisms 268 is blocked. When the sub-transmission gear mechanism 251 is set to a gear position other than neutral, power is transmitted from the linear motor 64b to the left and right planetary gear mechanisms 268 via the sub-transmission low-speed gear 254, the sub-transmission medium speed gear 255, or the sub-transmission high speed gear 256. Communicated.

On the other hand, when the output of the swing pump 70a is set to the neutral state and the swing brake 279 is turned on, power transmission from the swing motor 70b to the left and right planetary gear mechanisms 268 is blocked. When the output of the swing pump 70a is set to a state other than neutral and the swing brake 279 is turned off, the rotational power of the swing motor 70b is transmitted to the left ring gear 273 via the left input gear mechanism 282 and the reverse gear 284. On the other hand, it is transmitted to the right ring gear 273 via the right input gear mechanism 283.

During forward rotation (reverse rotation) of the turning motor 70b, the left ring gear 273 rotates in the reverse direction (forward rotation) and the right ring gear 273 rotates in the forward direction (reverse rotation) at the same rotation speed in the opposite directions. In other words, the shift output of each motor shaft 260, 261 is transmitted to the drive sprocket 51 of the left and right crawler belts 2 via the auxiliary transmission gear mechanism 251 or the left and right differential mechanisms 257, respectively, and the vehicle speed (travel Speed) and direction of travel are determined.

That is, when the rectilinear motor 64b is driven with the turning motor 70b stopped and the left and right ring gears 273 stationary, the rotational output of the rectilinear motor shaft 260 is transmitted to the left and right sun gears 271 at the same left and right rotational speed, and the planetary gear 272 is driven. The left and right crawler belts 2 are driven at the same rotational speed in the same direction via the carrier 274, and the traveling machine body 1 travels straight.

Conversely, when the turning motor 70b is driven with the linear motor 64b stopped and the left and right sun gears 271 stationary, the left ring gear 273 is rotated forward (reversely) by the rotational power of the turning motor shaft 261 and the right ring gear. 273 reversely rotates (forward rotation). As a result, one of the drive sprockets 51 of the left and right crawler belts 2 rotates forward and the other rotates backward, and the traveling machine body 1 changes its direction on the spot (also referred to as a pivot or spin turn).

Further, when the left and right ring gears 273 are driven by the turning motor 70b while the left and right sun gears 271 are driven by the straight motor 64b, a difference occurs in the speeds of the left and right crawler belts 2, and the traveling machine body 1 turns forward while moving forward or backward. Turn left or right (U-turn) with a turning radius greater than the radius. The turning radius at this time is determined according to the speed difference between the left and right crawler belts 2. The engine 7 turns left or right while the driving force of the engine 7 is always transmitted to the left and right crawler belts 2.

Next, the hydraulic circuit structure of the vehicle drive device will be described with reference to FIG. The hydraulic circuit 200 of the vehicle drive device includes a rectilinear pump 64a, a rectilinear motor 64b, a swing pump 70a, a swing motor 70b, and a transmission charge pump 151. The rectilinear pump 64a and the rectilinear motor 64b are connected in a closed loop by a rectilinear first oil passage 201a and a rectilinear second oil passage 201b. A straight traveling first oil passage 201 a and a straight traveling second oil passage 201 b constitute a straight traveling oil passage 201. The turning pump 70a and the turning motor 70b are connected in a closed loop by a turning first oil passage 202a and a turning second oil passage 202b. The turning first oil passage 202 a and the turning second oil passage 202 b constitute the turning closed oil passage 202. By driving the rectilinear pump 64a and the swing pump 70a with the rotational power of the engine 7 and controlling the swash plate angle of the rectilinear pump 64a and the swing pump 70a, the discharge direction and discharge of hydraulic oil to the rectilinear motor 64b and the swing motor 70b The amount is changed, and the rectilinear motor 64b and the turning motor 70b operate forward and backward.

As shown in FIG. 7, the hydraulic circuit 200 of the vehicle drive device is connected to the transmission charge pump 151 via the rectilinear valve 203 that switches in response to manual operation of the main transmission lever 44 and the rectilinear valve 203. And a rectilinear cylinder 204. When the rectilinear valve 203 is switched and operated, the rectilinear cylinder 204 is actuated to change the swash plate angle of the rectilinear pump 64a, and the rectilinear motor shaft 260 of the rectilinear motor 64b changes the rotational speed of the rectilinear motor shaft steplessly or reversely. The action is executed. Further, the hydraulic circuit 200 of the vehicle drive device also includes a hydraulic servo mechanism 205 for linear shift. The hydraulic servo mechanism 205 executes a feedback operation in which the rectilinear valve 203 returns to neutral by controlling the swash plate angle of the rectilinear pump 64a, and changes the swash plate angle of the rectilinear pump 64a in proportion to the manual operation amount of the main transmission lever 44, The rotational speed of the linear motor shaft 260 of the linear motor 60b is changed.

On the other hand, the hydraulic circuit 200 of the vehicle drive device includes a swing valve 206 that switches in response to manual operation of the steering handle 43 and a swing cylinder 207 that is connected to the transmission charge pump 151 via the swing valve 206. ing. When the swing valve 206 is switched, the swing cylinder 207 is operated to change the swash plate angle of the swing pump 70a, and the left / right swing that continuously changes or reverses the rotation speed of the swing motor shaft 261 of the swing motor 70b. The operation is executed, and the traveling machine body 1 changes the traveling direction to the left and right to change the direction at the field headland and to correct the course. The hydraulic circuit 200 of the vehicle drive device also includes a hydraulic servo mechanism 208 for turning and shifting. The hydraulic servo mechanism 208 performs a feedback operation in which the swing valve 206 returns to neutral by controlling the swash plate angle of the swing pump 70a, and changes the swash plate angle of the swing pump 70a in proportion to the amount of manual operation of the steering handle 43. The rotation speed of the swing motor shaft 261 of the swing motor 70b is changed.

As shown in FIG. 7, a charge branching oil passage 219 (details will be described later) is connected to all the oil passages 201a, 201b, 202a, 202b of both the closed oil passages 201, 202. A check valve 211 for the straight traveling first oil passage 201a is provided between the charge branching oil passage 219 and the straight traveling first oil passage 201a. A check valve 211 for the straight second oil passage 201b is provided between the charge branch oil passage 219 and the straight second oil passage 201b. Accordingly, the straight oil closing path 201 includes two check valves 211. Further, a check valve 212 for the turning first oil passage 202a is provided between the charge branch oil passage 219 and the turning first oil passage 202a. A check valve 212 for the turning second oil passage 202b is provided between the charge branch oil passage 219 and the turning second oil passage 202b. Therefore, the turning oil closing path 202 also includes two check valves 212.

A straight bypass oil passage 213 is connected to the straight advance first oil passage 201a and the straight advance second oil passage 201b. A rectilinear side bidirectional relief valve 215 is provided in the rectilinear bypass oil passage 213. A turning bypass oil passage 214 is connected to the turning first oil passage 202a and the turning second oil passage 202b. A turning-side bidirectional relief valve 216 is provided in the turning bypass oil passage 214. Accordingly, each of the closed oil passages 201 and 202 includes one bidirectional relief valve 215 and 216.

Now, the suction side of the transmission charge pump 151 is connected to a strainer 217 in the mission case 63. A charge introduction oil passage 218 is connected to the discharge side of the transmission charge pump 151. A charge branch oil passage 219 is connected to the downstream side of the charge introduction oil passage 218. As described above, the charge branch oil passage 219 is connected to all the oil passages 201a, 201b, 202a, 202b of the both closed oil passages 201,202. Therefore, while the engine 7 is being driven, the hydraulic oil from the transmission charge pump 151 is always replenished to both the closed oil passages 201 and 202. The charge branch oil passage 219 is connected to the rectilinear cylinder 204 via the rectilinear valve 203 and is also connected to the pivot cylinder 207 via the pivot valve 206. The charge branch oil passage 219 is connected to a continuously variable transmission case 323 and a transmission case 63 to be described later via a surplus relief valve 220. Therefore, the excess hydraulic oil from the transmission charge pump 151 is returned to the transmission case 63 via the excessive relief valve 220 via the continuously variable transmission case 323.

Next, a driving operation structure such as the steering handle 43 will be described with reference to FIGS. As shown in FIG. 8, a step frame 311 constituting a footrest flat portion for boarding an operator in the cab 5 is provided. A plurality of support leg frames 312 are erected on the upper surface side of the traveling machine body 1, and a step frame 311 is installed on the upper end side of the support leg frame 312. A step for getting on and off (not shown) is fixed to the side surface of the support frame 312 on the outer side of the right side of the step frame 311, and a hydraulic oil tank 315 is disposed on the inner side of the step for getting on and off (not shown). A hydraulic valve unit body 314 is attached below the front end of the step frame 311 on the upper surface.

Further, a steering case 318 having a steering operation shaft 316 and a continuously variable transmission operation shaft 317 is provided. Both ends of the case support horizontal frame 319 are connected between the left and right support frame 312 on the front lower surface side of the step frame 311, and the steering case 318 is detachably fastened to the substantially horizontal case support horizontal frame 319. A steering case 318 is supported in a multistage manner via a case support lateral frame 319 immediately above the hydraulic valve unit body 314. A steering operation shaft 316 protrudes upward from the upper surface of the steering case 318, and the steering operation shaft 316 is connected to the steering handle 43 via the steering shaft 321, and from the left side surface of the steering case 318 to the left side. A continuously variable transmission operation shaft 317 is protruded toward the main transmission lever 44, and the continuously variable transmission operation shaft 317 is connected to the main transmission lever 44 via a continuously variable transmission operation rod 322.

In addition, a continuously variable transmission case 323 in which a straight hydraulic continuously variable transmission 64 and a swing hydraulic continuously variable transmission 70 are assembled is provided. A continuously variable transmission case 323 is fixed to the upper right side of the transmission case 63, and the continuously variable transmission operation arm bodies 324 for straight travel and turning are arranged on the front and rear surfaces of the continuously variable transmission case 323. Each of the continuously-advancing and turning continuously variable speed operation arm bodies 324 is connected to a straight-ahead control link 345 and a turning control link 346 provided on the rear side of the steering case 318, respectively, and the steering operation of the steering handle 43 and the main transmission lever 44 are connected. In this speed change operation, the linear hydraulic continuously variable transmission 64 and the turning hydraulic continuously variable transmission 70 are controlled to change the course and the moving speed of the left and right crawler belts 2.

The hydraulic oil tank 315 is disposed below the right side of the rectangular step frame 311 in plan view, the continuously variable transmission case 323 is disposed below the left side of the step frame 311, and the hydraulic valve unit is disposed below the front portion of the step frame 311. Since the body 314 and the steering case 318 are arranged in the upper and lower multi-stage shape, the engine 7 (hydraulic oil pump) at the rear of the steering case 318 is interposed through a space formed between the hydraulic oil tank 315 and the continuously variable transmission case 323. It is possible to easily extend the hydraulic piping between the front hydraulic valve unit body 314, the hydraulic oil tank 315, and the hydraulic actuators (lifting hydraulic cylinder 4) of each part, and it is possible to improve the maintenance workability of the hydraulic equipment.

Next, the schematic structure of the mission case 63 will be described with reference to FIGS. As shown in FIG. 8, the engine 7 is mounted on the right side of the upper surface of the traveling machine body 1, and a mission case 63 is disposed in front of the center of the lateral width of the traveling machine body 1. An engine output pulley 168 is pivotally supported on the left end portion of the output shaft 65 of the engine 7, and the engine output belt 67 is wound around the mission input pulley 169 and the engine output pulley 168 on the upper left side of the mission case 63. The output of the engine 7 is transmitted to the hydraulic continuously variable transmissions 64 and 70 of the transmission case 63 via the engine output belt 67.

The mission case 63 has a bifurcated structure that is vertically long and can be divided into left and right, and has a substantially hollow box shape by fastening with a plurality of bolts. The lower part of the mission case 63 has a bifurcated shape projecting outward in the left and right directions and projects downward, and is roughly a gate shape when viewed from the front. Axle case 336 that protrudes left and right outwards is bolted to gear case portion 335 that protrudes downward from the lower left and right side surfaces of transmission case 63. The axles 278 are rotatably supported in the left and right axle cases 336, respectively. A drive sprocket 51 (see FIGS. 1, 2 and 6) is attached to the projecting ends of the left and right axles 278. As shown in FIG. 8, the bottom portions of the left and right gear case portions 335 are located below the bottom portion of the transmission case 63, and the bottom portions of the transmission case 63 are higher than the left and right axle cases 336.

On the upper right side of the mission case 63, a continuously variable transmission case 323 assembled with straight and turning hydraulic continuously variable transmissions 64 and 70 is attached. In this case, the rectilinear hydraulic continuously variable transmission 64 (the rectilinear pump 64a and the rectilinear motor 64b) is positioned on the front side in the continuously variable transmission case 323, and the swing hydraulic continuously variable transmission 70 (the swing pump 70a and the swivel) on the rear side. The motor 70b) is located. In the transmission case 63, gear trains such as the auxiliary transmission gear mechanism 251 and the differential mechanism 257 described with reference to FIG. 6 are accommodated.

A linear operation shaft 325 for operating the swash plate of the linear pump 64a to change the discharge direction and discharge amount of the hydraulic oil to the linear motor 64b is projected forward on the front side of the continuously variable transmission case 323. When the rectilinear operation shaft 325 is rotated around the axis, the swash plate angle of the rectilinear pump 64a is changed, and the discharge direction and discharge amount of the hydraulic oil to the rectilinear motor 64b are changed. On the rear surface side of the continuously variable transmission case 323, a turning operation shaft 326 for operating the swash plate of the turning pump 70a to change the discharge direction and the discharge amount of hydraulic oil to the turning motor 70b is protruded rearward. If the turning operation shaft 326 is turned around the axis, the swash plate angle of the turning pump 70a is changed, and the discharge direction and the discharge amount of hydraulic oil to the turning motor 70b are changed.

As shown in FIG. 9, a transmission charge pump 151 is attached to a portion corresponding to the turning pump 70a on the right outer surface of the continuously variable transmission case 323. The transmission charge pump 151 is connected to a strainer 221 (see FIG. 7) on the inner bottom side of the transmission case 63 via a suction hose 337 extending vertically. As described above, the transmission charge pump 151 is rotationally driven by the pump shaft 259 of the swing pump 70a. The hydraulic oil on the inner bottom side of the transmission case 63 is sucked into the charge pump 151 via the strainer 221 and the suction hose 337 by the drive of the transmission charge pump 151, and the oil passages 201, 202, 211 of the hydraulic circuit 200 are sucked. , 212, 217 to 210, 222 to 224, etc.

As shown in FIG. 9, a parking brake arm 338 for braking the parking brake 266 is provided on the right side surface of the mission case 63 below the turning motor 70b. When the parking brake 266 is braked by the braking operation of the parking brake arm 338, the parking brake shaft 265 and the auxiliary transmission output gear 267 are locked so as not to rotate, and the straight output toward the left and right drive sprockets 51 is stopped. When the steering handle 43 and the auxiliary transmission gear mechanism 251 are neutral, the turning brake 279 maintains the turning motor shaft 261 in a stopped (unrotatable) state. As a result, the output of the turning motor 70b, that is, the turning output toward the left and right drive sprockets 51 is stopped.

As shown in FIG. 8 to FIG. 10, an auxiliary transmission arm 339 for operating the auxiliary transmission shifters 252 and 253 of the auxiliary transmission gear mechanism 251 is provided on the front side of the transmission case 63. The auxiliary transmission arm 339 is interlocked with the auxiliary transmission lever 45 on the steering column 41. By operating the sub-transmission arm 339 via the sub-transmission lever 45, the sub-transmission shifters 252 and 253 are switched in conjunction with each other, and the output rotational speed of the linear motor shaft 260 is in three stages: low speed, medium speed or high speed. It is alternatively switched to the gear stage.

As shown in FIGS. 8 and 10, a mission input shaft 66, which is connected to the straight pump 64a and the swing pump 70a so as to be able to transmit power, projects outwardly on the upper left side of the mission case 63. A mission input pulley 169 is fixed to the projecting end side of the mission input shaft 66, and an engine output belt 67 is wound around the mission input pulley 169. An oil sump 340 (see FIG. 11) is formed on the upper front side in the mission case 63. Although detailed illustration is omitted, one end side of the upper external pipe is connected to the upper surface side of the oil sump 340 in the transmission case 63, and the other end side of the upper external pipe is connected to the upper surface side of the continuously variable transmission case 323. Yes. The hydraulic fluid sucked up by the transmission charge pump 151 from the inner bottom side of the transmission case 63 is used by the hydraulic continuously variable transmissions 64 and 70 in the continuously variable transmission case 323 and from the continuously variable transmission case 323 via the upper external pipe. Then, it flows into the oil sump 340 and is stored.

A lateral external pipe 341 is disposed below the mission input pulley 169 on the left side surface of the mission case 63. The lateral external pipe 341 is externally attached to the mission case 63. One end of the lateral external pipe 341 is connected to the oil sump 340 on the left side of the mission case 63. The other end of the lateral external pipe 341 is connected to the turning motor shaft 261 (the turning brake 279) on the left side of the mission case 63. The hydraulic oil in the oil sump 340 is sent directly to the turning brake 279 of the turning motor shaft 261. The turning brake 279 is lubricated by the hydraulic oil from the oil sump 340.

Below the lateral external pipe 341 on the left side surface of the transmission case 63, a straight vehicle speed sensor 293 for the straight pulse 292 on the parking brake shaft 265 and a turning vehicle speed sensor 295 for the turning pulser 294 of the steering counter shaft 280 are provided. Provided. Both vehicle speed sensors 293 and 295 are arranged in the front-rear direction on the left side surface of the mission case 63, and the straight vehicle speed sensor 293 is located on the front side and the turning vehicle speed sensor 295 is located on the rear side. In the embodiment, two vehicle speed sensors 293 and 295 are provided for each of the corresponding pulsers 292 and 294 from the viewpoint of fail-safe.

The straight-running pulser 292 has a diameter larger than that of a conventional structure (see, for example, Japanese Patent Application Laid-Open No. 2012-82918) and has a predetermined width (see FIGS. 12 and 14). Then, the straight outer pulsar 292 is configured to detect the thick outer peripheral side by the straight vehicle speed sensor 293. These are made for the purpose of avoiding the interference with the cutting portion 3 and the like so that the straight-running pulser 292 and the straight-traveling vehicle speed sensor 293 do not protrude greatly to the left outer side of the mission case 63.

Incidentally, FIG. 19 shows a mounting structure of the axle 278 and the drive sprocket 51 with respect to the axle case 336. As shown in FIG. 19, an axle 278 is rotatably supported in the axle case 336 via both shield type bearings 388. The front end side of the axle shaft 278 protrudes outward from the axle case 336. A spline portion 278c into which the boss portion 51a of the drive sprocket 51 is fitted and a screw portion 278d into which the nut 390 is screwed through a washer 389 are formed on the front end side of the axle shaft 278. The boss 51a of the drive sprocket 51 is spline-fitted to the spline 278c of the axle 278, and the nut 390 is screwed into the screw 278d of the axle 278 via the washer 389, whereby the drive sprocket 51 is integrated with the front end of the axle 278. It is mounted to rotate.

A bearing oil seal 391 that seals the left and right outer sides of both shield type bearings 388 is fitted into the opening side of the axle case 336. A bearing oil seal 391 is fitted on the outer peripheral side of a bearing seal collar 51 b that extends inward from the boss 51 a of the drive sprocket 51 in the left and right directions. A bearing oil seal 391 closes the opening side of the axle case 336. On the left and right inner side surfaces of the drive sprocket 51, an annular anti-roll wheel 392 is formed so as to protrude inward in the left and right direction so as to be positioned concentrically with the bearing seal collar 51b. In a state where the drive sprocket 51 is mounted on the tip end side of the axle shaft 278, the wrapping prevention ring body 392 is fitted on the stepped portion 336a on the outer peripheral side of the opening of the axle case 336. By fitting the stepped portion 336a of the axle case 336 and the anti-roll wheel 392, it is possible to prevent field grass and mud from entering between the axle case 336 and the drive sprocket 51.

A stop ring 393 for restricting the displacement of the two shield type bearings 388 to the left and right outer sides is detachably mounted on the inner peripheral side of the axle case 336. A positioning collar 394 that restricts the displacement of the two shielded bearings 388 toward the left and right inner sides is fitted to the left and right inner parts of the axle shaft 278 relative to the two shielded bearings 388. In a state where the drive sprocket 51 is mounted on the front end side of the axle shaft 278, both shielded bearings 388 are clamped by the retaining ring 393 and the positioning collar 394 so that they cannot be displaced. The bearing seal collar 51 b of the drive sprocket 51 is in contact with the stop ring 393.

Between the front end side of the spline part 278c of the axle shaft 278 and the washer 389, an annular packing body 395 made of rubber is disposed. The packing body 395 is in close contact with the tip end side of the spline portion 278c and the washer 389. In the embodiment, lubricating oil (grease or gear oil) is sealed between the boss portion 51a of the drive sprocket 51 and the spline portion 278c of the axle shaft 278. The close contact structure of the packing body 395 suppresses leakage of lubricating oil from between the boss portion 51a and the spline portion 278c, and intrusion of muddy water or the like between the boss portion 51a and the spline portion 278c and eventually into the axle case 336. Is suppressed. By using the packing body 395, the sealing performance between the boss portion 51a and the spline portion 278c is improved as compared with the conventional structure (for example, see Japanese Patent Application Laid-Open No. 2012-231707).

Next, the internal structure of the mission case 63 will be described with reference mainly to FIGS. As shown in FIGS. 11 to 13, a pair of left and right differential mechanisms 257 (planetary gear mechanisms 268) are arranged on the inner bottom side of the mission case 63. Each planetary gear mechanism 268 is placed on the left and right with a center gear 276 fixed to the sun gear shaft 275 extending in the left and right direction. Above the planetary gear mechanism 268, a parking brake shaft 265, a steering output shaft 285, and a rotating shaft of the reverse gear 284, which are positioned on the output side of the auxiliary transmission gear mechanism 251, are arranged side by side. A central intermediate gear 289 that always meshes with the downstream reduction gear 286 is fixed to the middle part of the steering output shaft 285 (between the left intermediate gear 287 and the right intermediate gear 288). In the embodiment, the center gear 276 and the center intermediate gear 289 are in a positional relationship such that the center gear 276 interferes with the center intermediate gear 289 when the center gear 276 has a normal spur gear shape. For this reason, the center gear 276 of the embodiment has a substantially saddle shape with the outer peripheral portion curved to the left (the outer peripheral portion is offset from the rotation center to the left), and the center intermediate gear on the steering output shaft 285. Interference with 289 is avoided.

An auxiliary transmission countershaft 270 is disposed between the planetary gear mechanism 268 and the steering output shaft 285 in the front-rear direction and on the upper side. A steering counter shaft 280 is disposed behind the auxiliary transmission counter shaft 270. A rectilinear motor shaft 260 is disposed above the auxiliary transmission counter shaft 270. A turning motor shaft 261 is disposed above the steering counter shaft 280. A turning brake 279 is provided on the turning motor shaft 261. A pump shaft 258 of the rectilinear pump 64a is disposed above the rectilinear motor shaft 260. A pump shaft 259 of the swing pump 70a is disposed above the swing motor shaft 261. A mission input shaft 66 is disposed between the front and rear directions of both pump shafts 258 and 259 and on the upper side.

As shown in FIG. 11, in the mission case 63, the height position of the hydraulic oil surface during driving of the engine 7 is set such that the parking brake shaft 265 and the steering output shaft 285 are immersed in the hydraulic oil. Therefore, in the transmission case 63, the auxiliary transmission countershaft 270, the steering countershaft 280, and the shafts 66, 258 to 261 located above them are positioned above the hydraulic oil surface. These seven shafts 66, 258 to 261, 270, and 280 do not rotate while immersed in the hydraulic oil, and suppress an increase in stirring resistance (an increase in power loss).

11, 12, and 14, the auxiliary transmission gear mechanism 251, which is an example of the transmission gear mechanism, is divided into an input side gear portion 351 and an output side gear portion 352. In the embodiment, a low-speed relay gear 354, a medium-speed relay gear 355, and a high-speed relay gear 356 are pivotally supported on an auxiliary transmission countershaft 270 that is an input-side transmission shaft as the input-side gear portion 351. The low speed relay gear 354 and the medium speed relay gear 355 are fixed to the auxiliary transmission counter shaft 270. The high-speed relay gear 356 is loosely fitted to the auxiliary transmission countershaft 270 so as to be rotatable. Further, as the output side gear portion 352, the auxiliary transmission low speed gear 254, the auxiliary transmission medium speed gear 255, and the auxiliary transmission high speed gear 256 are pivotally supported on the parking brake shaft 265 that is the output side transmission shaft. The auxiliary transmission low speed gear 254 and the auxiliary transmission intermediate speed gear 255 are loosely fitted to the parking brake shaft 265 so as to be rotatable. The auxiliary transmission high speed gear 256 is fixed to the parking brake shaft 265. By the sliding movement of the low speed auxiliary transmission shifter 252, the auxiliary transmission low speed gear 254 and the auxiliary transmission intermediate speed gear 255 are selectively connected to the parking brake shaft 265. The auxiliary transmission high speed gear 256 is connected to the auxiliary transmission counter shaft 270 by the sliding movement of the high speed auxiliary transmission shifter 253.

As can be seen from FIG. 11, in the transmission case 63, the auxiliary transmission countershaft 270 that is the input side of the auxiliary transmission is positioned above the parking brake shaft 265 that is the output side of the auxiliary transmission. Therefore, in the transmission case 63, the input side gear portion 351 (354 to 356) attached to the auxiliary transmission countershaft 270 and the output side gear portion 352 (254 to 256) attached to the parking brake shaft 265 are divided up and down. Are placed close together. Further, as described above, in the mission case 63, the height position of the hydraulic oil surface during driving of the engine 7 is set to such an extent that the parking brake shaft 265 is immersed in the hydraulic oil. Accordingly, a part of the output side gear portion 352 is immersed in the hydraulic oil in the mission case 63. The input side gear portion 351 is located above the hydraulic oil surface in the mission case 63 and does not rotate in a state where it is immersed in the hydraulic oil.

As shown in FIG. 14, the hydraulic oil splashed by the output side gear portion 352 (254 to 256) is guided to the input side gear portion 351 (354 to 356) to the auxiliary transmission countershaft 270 which is the input side of the subshift. A T-shaped lubrication passage 357 is formed. In the embodiment, the fitting recesses 358 and 359 are formed in the left and right inner walls of the mission case 63. One end of the auxiliary transmission countershaft 270 is rotatably fitted in the right fitting recess 358 via an open type bearing 360. The other end side of the auxiliary transmission countershaft 270 is rotatably fitted in the left fitting recess 359 via an open type bearing 361. An inlet 357 a of the lubrication passage 357 is opened at one end surface of the auxiliary transmission counter shaft 270. The inflow port 357 a of the lubrication passage 357 faces the right fitting recess 358. Two outlets 357 b of the lubricating passage 357 are opened on the outer peripheral surface of the auxiliary transmission counter shaft 270. Each outlet 357 b of the lubrication passage 357 faces the inner peripheral side of the high-speed relay gear 356 close to the high-speed auxiliary transmission shifter 253.

In this case, the hydraulic fluid splashed by the output side gear portion 352 (254 to 256) splashes from the outer peripheral side to the input side gear portion 351 (354 to 356) including the high-speed auxiliary transmission shifter 253. A part of the splashed hydraulic oil enters the right fitting recess 358 via the right open bearing 360, and the high speed relay gear 356 via the lubrication passage 357 communicating with the right fitting recess 358. And the high-speed auxiliary transmission shifter 253 in the vicinity thereof. As a result, the high-speed relay gear 356 and the high-speed auxiliary transmission shifter 253 are lubricated.

As is apparent from the above description and FIGS. 11, 12, and 14, the continuously variable transmissions 64, 70 that continuously change the power of the engine 7 and a plurality of shift outputs of the continuously variable transmissions 64, 70 are provided. In the vehicle drive device including a transmission case 63 incorporating a transmission gear mechanism 251 that switches between stages, the transmission gear mechanism 251 is divided into an input side gear portion 351 and an output side gear portion 352, and the output side gear portion. A part of 352 is immersed in the hydraulic oil in the mission case 63 and the input side gear portion 351 is positioned above the hydraulic oil surface in the mission case 63 in the mission case 63 so that the input side Since the gear portion 351 and the output side gear portion 352 are arranged close to each other in the vertical direction, the hydraulic oil surface is rotated by the rotation of the output side gear portion 352. Hydraulic oil can be splashed onto the input side gear portion 351 at a higher position, and therefore the input side can be operated without increasing the amount of hydraulic oil used by setting the hydraulic oil level in the transmission case 63 high. The gear portion 351 can be reliably lubricated. Since the input side gear portion 351 is not immersed in the hydraulic oil, problems such as an increase in power loss and a significant increase in the hydraulic oil temperature can be suppressed.

In particular, according to the embodiment, hydraulic oil splashed by the output side gear portion 352 can be supplied to the inner peripheral side of the input side gear portion 351 via the lubrication passage 357 of the input side transmission shaft 270. The lubricity of the gear portion 351 (specifically, the high-speed auxiliary transmission shifter 253 and the high-speed relay gear 356) can be further improved.

As shown in FIGS. 10, 12, and 15, a PTO boss portion 365 as a cylindrical portion is integrally formed below the lateral external pipe 341 on the left side surface of the mission case 63. A PTO shaft 366 (see FIG. 16) as a shaft member that transmits power to the reaping portion 3, the threshing portion 9, or the like can be attached to the PTO boss portion 365. The ordinary combine according to the embodiment employs a configuration in which the driving force of the engine 7 is directly transmitted to the cutting unit 3, the threshing unit 9, and the like, so that the PTO shaft 366 is unnecessary. Therefore, the PTO boss portion 365 is not fitted with the PTO shaft 366, and the opening of the PTO boss portion 365 is closed with the sealing lid 364 (see FIGS. 12 and 15).

FIG. 16 shows an example in which the vehicle drive device of the present application is applied to a self-removable combine and a PTO shaft 366 is mounted on the PTO boss portion 365. In the example of FIG. 16, a PTO shaft 366 is rotatably supported on the PTO boss portion 365 via bearing bodies 367 and 368. The bearing bodies 367 and 368 are paired in the axial direction of the PTO shaft 366. A PTO pulley 369 is mounted on the outer end side of the PTO shaft (end portion outside the transmission case 63). A PTO output gear 370 as a rotating member that transmits power from the auxiliary transmission countershaft 270 is mounted on the inner end side of the PTO shaft 366 (end portion in the transmission case 63). In this case, a PTO input gear 371 is mounted between the low speed relay gear 354 and the medium speed relay gear 355 in the auxiliary transmission countershaft 270. The PTO input gear 371 is always meshed with the PTO output gear 370. Therefore, the PTO shaft 366 is always driven to rotate while the engine 7 is driven by the driving force (the driving force of the linear motor 64b) via the linear motor shaft 260 and the auxiliary transmission counter shaft 270.

Step portions 373 and 374 projecting radially outward are formed on the inner peripheral side of the PTO boss portion 365. A first step portion 373 corresponding to the first bearing body 367 is formed at a location outside the transmission case 63 on the inner peripheral side of the PTO boss portion 365. A second stepped portion 374 corresponding to the second bearing body 368 is formed at a position closer to the inside of the mission case 63 on the inner peripheral side of the PTO boss portion 365. A large-diameter portion 375 having a larger diameter than the inner diameter of the bearing bodies 367 and 368 is formed at the end of the PTO shaft 366, or a PTO output gear 370 having a larger diameter than the inner diameter of the bearing bodies 367 and 368 can be attached and detached. Wearing. In the example of FIG. 16, a large diameter portion 375 having a larger diameter than the inner diameter of the first bearing body 367 is formed on the outer end side of the PTO shaft 366. A PTO output gear 370 having a diameter larger than that of the second bearing body 368 is coupled to the inner end side of the PTO shaft 366 so as to be slidable in the axial direction and not relatively rotatable (spline fitting).

The first bearing body 367 is sandwiched from both sides in the axial direction by the large diameter portion 375 and the first step portion 373. Further, the second bearing body 368 is clamped from both sides in the axial direction by the PTO output gear 370 and the second stepped portion 374. That is, the bearing bodies 367 and 368 are sandwiched between the large diameter portion 375 or the PTO output gear 370 and the step portions 373 and 374 in the PTO boss portion 365. A retaining ring 376 is detachably attached to a portion of the PTO shaft 366 closer to the inside of the transmission case 63 than the PTO output gear 370.

When configured as described above, the PTO shaft 366 can be easily pulled out from the PTO boss portion 365 by removing the retaining ring 376 with the mission case 63 separated into the left and right. Conversely, when mounting the PTO shaft 366 to the PTO boss portion 365, after mounting the pair of bearing bodies 367 and 368 on the PTO boss portion 365 with the transmission case 63 separated into the left and right sides, The retaining ring 376 may be mounted by inserting the PTO shaft 366 into the inner peripheral side of the bearing bodies 367 and 368 and spline-fitting the PTO output gear 370 to the inner end side of the PTO shaft 366. The presence of both stepped portions 373 and 374 makes it possible to restrict the positions of both bearing bodies 367 and 368 only by mounting the PTO shaft 366 and the PTO output gear 370.

Therefore, the configuration of the vehicle drive device (mission case 63) can be simplified to the specifications with the PTO shaft 366 and the specifications without the PTO shaft 366 by attaching / detaching the PTO shaft 366, the PTO output gear 370, and the like and detaching the sealing lid 364. Can be changed. One type of vehicle drive device (mission case 63) can be shared by two specifications for the self-removal combiner and the ordinary combiner, and the manufacturing cost can be reduced. In the example of FIG. 16, the shaft diameters on both sides of the large diameter portion 375 in the PTO shaft 366 are set to the same diameter.

As is apparent from the above description and FIGS. 12, 15, and 16, in the vehicle drive device including the transmission case 63 for shifting the power of the engine 7, a bearing is provided in the cylindrical portion 365 formed in the transmission case 63. The shaft member 366 is rotatably supported via the bodies 367 and 368, and step portions 373 and 374 projecting radially inward are formed on the inner peripheral side of the cylindrical portion 365. A large-diameter portion 375 having a larger diameter than the inner diameter of the bearing bodies 367 and 368 is formed at the end of the shaft member 366, or a rotating member 370 having a larger diameter than the inner diameter of the bearing bodies 367 and 368 can be attached and detached. The bearing bodies 367 and 368 are sandwiched between the large-diameter portion 375 or the rotating member 370 and the step portions 373 and 374 in the cylindrical portion 365, so that the bearing body There is no need to use a dedicated parts of the snap ring or the like for the position regulation of 67,368. Therefore, the number of parts can be reduced, the shaft support structure of the shaft member 366 can be simplified, the assembly work can be rationalized, and the manufacturing cost can be reduced.

In particular, according to the example of FIG. 16, the bearing bodies 367 and 368 are paired in the axial direction of the shaft member 366, and the stepped portions 373 and 374 are the missions of the pair of bearing bodies 367 and 368. A first step 373 corresponding to the first bearing body 367 on the outer side of the case 63 and a second step corresponding to the second bearing body 368 on the inner side of the transmission case 63 of the pair of bearing bodies 367 and 368. The large-diameter portion 375 is formed at the end portion of the shaft member 366 on the outer side of the transmission case 63, and the end portion of the shaft member 366 on the inner side of the mission case 63 is formed. The rotating member 370 is detachably attached to the first bearing body 367 by the large diameter portion 375 and the first step portion 373, and the rotation The second bearing body 368 is sandwiched between the material 370 and the second stepped portion 374, and a retaining ring 376 is attached to a portion of the shaft member 366 that is further inside the transmission case 63 than the rotating member 370. Thus, the shaft member 366, the pair of bearing bodies 367, 368, and the rotating member 370 can be appropriately attached to the cylindrical portion 365 of the transmission case 63 with only one retaining ring 376, and the The shaft member 366 can be assembled. The maintainability of the shaft support structure of the shaft member 366 can be improved.

In addition, since the shaft diameters on both sides of the large diameter portion 375 are set to the same diameter in the shaft member 366, the processing cost of the shaft member 366 can be reduced, which in turn contributes to the cost reduction of parts.

As described above, in the vehicle drive device of the embodiment, a wet multi-plate swing brake 279 is provided on the swing motor shaft 261 (see FIGS. 13 and 17). In the embodiment, the mounting hole 379 is opened in the upper and lower middle part of the left side surface of the mission case 63. Bolts are fastened in a state in which a cylindrical brake housing 380 is fitted in the mounting hole 379. The swing motor shaft 261 includes a cylindrical brake cylinder shaft portion 381. The swing cylinder shaft 381 including the brake cylinder shaft 381 is extended into the transmission case 63 by spline fitting the brake cylinder shaft 381 to the protruding end of the swing motor shaft 261 protruding from the continuously variable transmission case 323. .

The right end side of the brake cylinder shaft portion 381 is rotatably supported on the right inner wall of the transmission case 63 via an open type bearing 382. The brake cylinder shaft 381 enters the inside of the brake housing 380. A mounting recess 383 is formed in the left bottom portion of the brake housing 380. The left end side of the brake cylinder shaft portion 381 is rotatably fitted in the mounting recess 383 of the brake housing 380 via an open bearing 384. That is, in the mission case 63, the swing motor shaft 261 including the brake cylinder shaft portion 381 is rotatably supported via a pair of open bearings 382 and 384. By connecting the other end side of the lateral external pipe 341 from the outside to the left bottom of the brake housing 380, the other end side of the lateral external pipe 341 and the brake cylinder shaft portion 381 are connected.

A turning input gear 385 that always meshes with the upstream reduction gear 281 on the steering counter shaft 280 is attached to the right end side of the brake cylinder shaft portion 381. An inner hub 386 is spline-fitted to the middle part of the left and right sides of the brake cylinder shaft 381. Friction plates 380a and 386a are alternately provided on the inner peripheral surface of the brake housing 380 and the outer peripheral surface of the inner hub 386. A compression spring 399 is fitted between the left open bearing 384 and the inner hub 386 in the brake cylinder shaft 381. When the output of the swing motor 70b is equal to or less than the predetermined torque, the friction plates 380a and 386a are pressed against each other by the elastic restoring force of the compression spring 399 to brake the brake cylinder shaft portion 381, and the swing motor shaft 261 is stopped (unrotatable) To maintain.

A plurality of lubrication holes 387 for communicating the inside and outside of the brake cylinder shaft portion 381 are formed in the side peripheral portion of the brake cylinder shaft portion 381. In the embodiment, a group of lubrication holes 387 are opened toward the inner peripheral side (spline portion) of the inner hub 386 and the inner peripheral side of the turning input gear 385. The hydraulic oil in the oil sump 340 is concentratedly supplied from the lateral external pipe 341 to the friction plates 380a and 386a through the mounting recess 383, the inner peripheral side of the brake cylinder shaft 381, and the lubricating holes 387. . That is, the turning brake 279 is lubricated by the hydraulic oil from the oil reservoir 340.

Since the brake housing 380 has a cylindrical shape, the hydraulic oil intensively supplied to the friction plates 380a and 386a easily collects inside the brake housing 380. Here, the left-side bearing 384 that supports the brake cylinder shaft 381 is an open type, but the left-side open type bearing 384 is reduced by reducing the slack of the mounting recess 383 with respect to the left-side open type bearing 384. The leakage of the hydraulic oil from 384 to the outside of the brake cylinder shaft portion 381 is suppressed.

As described above, in the embodiment, the auxiliary transmission countershaft 270, the steering countershaft 280, and the shafts 66 and 258 to 261 above them do not rotate when immersed in hydraulic oil. For this reason, although it contributes to the reduction of power loss, there is a concern about wear, a decrease in life, and the like. Therefore, the structure shown in FIG. 18 may be adopted. That is, one end side of the second horizontal external pipe 396 is connected to the oil reservoir 340 on the left side of the mission case 63 separately from the horizontal external pipe 341, and the other end side of the second horizontal external pipe 396 is connected to the mission case 63. The auxiliary transmission countershaft 270 is connected to the left side. The transmission case 63 is formed with a first internal oil passage 397 that connects the oil reservoir 340 and the linear motor shaft 260 and the other end of the lateral external pipe 341 or the turning motor shaft 261 (the turning brake). 279) and the steering countershaft 280 are connected to form a second internal oil passage 398. With this configuration, the linear motor shaft 260, the auxiliary transmission counter shaft 270, and the steering counter shaft 280 can also be lubricated by the hydraulic oil from the oil sump 340.

Next, the oil passage structure of the hydraulic transmission including the continuously variable transmission case 323 will be described with reference to FIGS. The hydraulic transmission according to the embodiment includes a continuously variable transmission case 323 including a pair of hydraulic continuously variable transmissions 64 and 70 formed by combining hydraulic pumps 64 a and 70 a and hydraulic motors 64 b and 70 b, and a continuously variable transmission case 323. And an oil passage block 401 attached to one side surface. In this case, a continuously variable transmission case 323 is attached to the upper right side of the mission case 63 via an oil passage block 401. The oil passage block 401 is held between the transmission case 63 and the continuously variable transmission case 323.

A linear hydraulic continuously variable transmission 64 including a linear pump 64a and a linear motor 64b is built in front of the midway part of the continuously variable transmission case 323. In the embodiment, the rectilinear pump 64a is positioned on the upper side in the continuously variable transmission case 323, and the rectilinear motor 64b is positioned on the lower side. A swing hydraulic continuously variable transmission 70 including a swing pump 70a and a swing motor 70b is built in the rear of the continuously variable middle case 323 in the middle of the front and rear. In the embodiment, the swing pump 70a is positioned on the upper side in the continuously variable transmission case 323, and the swing motor 70b is positioned on the lower side. Accordingly, in the continuously variable transmission case 323, the hydraulic pumps 64a and 70a are arranged in the front-rear direction, and the hydraulic motors 64b and 70b are also arranged in the front-rear direction. The transmission charge pump 151 is located at a position corresponding to the turning pump 70a on the right outer surface of the continuously variable transmission case 323.

A hydraulic servo mechanism 205 for linear shift is disposed in front of the linear hydraulic continuously variable transmission 64 in the continuously variable transmission case 323. In the continuously variable transmission case 323, a hydraulic servo mechanism 208 for turning and shifting is arranged behind the turning hydraulic continuously variable transmission 70. That is, in the continuously variable transmission case 323, hydraulic servo mechanisms 205 and 208 for operating the hydraulic continuously variable transmissions 64 and 70 are distributed and arranged on both ends of the both hydraulic continuously variable transmissions 64 and 70, respectively. . The straight operation shaft 325 protrudes forward on the front outer surface of the continuously variable transmission case 323, and the straight operation shaft 325 protrudes rearward on the rear outer surface of the continuously variable transmission case 323. Although not shown in detail, a linearly variable continuously variable operating arm 324 (see FIG. 8) is connected to the linearly operating shaft 325, and a rotationally variable continuously variable operating arm 324 is connected to the swing operating shaft 326. ing.

The oil passage block 401 is formed with closed loop oil passages 201 and 202 for the hydraulic continuously variable transmissions 64 and 70 and a charge branch oil passage 219 connecting both the closed loop oil passages 201 and 202. In the embodiment, a vertically long straight oil passage 201a is formed on the front side across the straight pump 64a and the straight motor 64b, and a vertically long straight oil passage 201b is formed on the rear side. The straight traveling first oil passage 201a and the straight traveling second oil passage 201b connect the straight traveling pump 64a and the straight traveling motor 64b in a closed loop shape. The rectilinear first oil passage 201a and the rectilinear second oil passage 201b constitute a rectilinear closed oil passage 201 corresponding to a straight loop closed oil passage. Further, a vertically long swirl first oil passage 202a is formed on the front side with the swivel pump 70a and the swivel motor 70b interposed therebetween, and a vertically long swirl second oil passage 202b is formed on the rear side. The turning first oil passage 202a and the turning second oil passage 202b connect the turning pump 70a and the turning motor 70b in a closed loop shape. The turning first oil passage 202a and the turning second oil passage 202b constitute a turning closed oil passage 202 corresponding to a turning closed-loop oil passage. Accordingly, in the oil passage block 401, the first straight oil passage 201a, the second straight oil passage 201b, the turning first oil passage 202a, and the turning second oil passage 202b are arranged in this order from the front.

On the upper side in the oil passage block 401, a charge branch oil passage 219 as a charge oil passage is formed to extend in the front-rear direction. The charge branch oil passage 219 includes all the oil passages 201a, 201b, 202a, 202b of the both closed oil passages 201, 202, that is, the straight first oil passage 201a, the straight second oil passage 201b, the turning first oil passage 202a and the turning. It penetrates the upper side of the second oil passage 202b back and forth. As can be seen from FIG. 20, the charge branch oil passage 219 and the charge branch oil passage 219 are orthogonal to each other of all the oil passages 201a, 201b, 202a, 202b of the both closed oil passages 201,202.

Also, the discharge side of the charge introduction oil passage 218 is communicated with the front and rear central portions of the charge branch oil passage 219. That is, the oil passage block 401 is provided with a communication port 218a that is connected to the discharge side of the charge introduction oil passage 218 in the upper surface portion above the front and rear central portions of the charge branch oil passage 219. A port 218a is drilled downward to communicate with the charge branch oil passage 219. Thereby, the charge introduction oil passage 218 communicated with the discharge side of the transmission charge pump 151 outside the oil passage block 401 communicates with the charge branch oil passage 219 in the oil passage block 401 via the communication port 218a.

As shown in FIGS. 20 to 22, the front and rear end portions of the charge branch oil passage 219 communicate with the corresponding hydraulic servo mechanisms 205 and 208 via the servo oil passages 402 and 403, respectively. Servo oil passages 402 and 403 connecting the charge branch oil passage 219 and the respective hydraulic servo mechanisms 205 and 208 are continuously variable from the oil passage block 401 so as to extend perpendicular to the charge branch oil passage 219 and in parallel with each other. It is formed toward 323. In the embodiment, the linear servo oil passage 402 for the linear shift hydraulic servomechanism 205 is provided on the inner side of the front end of the continuously variable transmission case 323, and the front side surface of the continuously variable transmission case 323 (near the hydraulic servo mechanism 205 for linear shift). It is formed in a straight line extending in the horizontal direction along the side surface. A turning servo oil passage 403 for the turning-speed hydraulic servomechanism 208 is provided inside the rear end of the infinitely-variable shifting case 323 on the rear side surface (side surface near the turning-speed changing hydraulic servo mechanism 208). It is formed in a straight line extending sideways along the side. Therefore, the servo oil passages 402 and 403 extend in a straight line in the horizontal direction in the plan view of FIG. 21 and are arranged in parallel to each other. Both hydraulic continuously variable transmissions 64 and 70 are located between both servo oil passages 402 and 403.

With this configuration, the servo oil passages 402 and 403 for the respective hydraulic servo mechanisms 205 and 208 are straight along the side surfaces (the front side surface and the rear side surface) near the respective hydraulic servo mechanisms 205 and 208 in the continuously variable transmission case 323. And can be formed as short as possible. Accordingly, the servo oil passages 402 and 403 can be easily formed in the continuously variable transmission case 323 and the oil passage block 401, the workability is good, and the manufacturing can be performed at low cost.

As shown in FIG. 20, check valves 211, 212 are arranged at orthogonal positions between all the oil passages 201 a, 201 b, 202 a, 202 b of the both closed oil passages 201, 202 and the charge branch oil passage 219. . In the embodiment, all the oil passages 201a, 201b, 202a, 202b of both the closed oil passages 201, 202 are opened at the upper end surface side of the oil passage block 401, and the check valves 211, 212 are inserted downward from the opening. And wearing. A check valve 211 for the straight traveling first oil passage 201a is mounted at an orthogonal position between the charge branch oil passage 219 and the straight traveling first oil passage 201a, and at a perpendicular position between the charge branch oil passage 219 and the straight traveling second oil passage 201b, A check valve 211 for the straight second oil passage 201b is mounted. And the check valve 212 with respect to the turning 1st oil path 202a is mounted in the orthogonal location of the charge branch oil path 219 and the turning 1st oil path 202a, and the orthogonal location of the charge branch oil path 219 and the turning 2nd oil path 202b In addition, a check valve 212 for the turning second oil passage 202b is mounted. Therefore, as described above, each of the oil closed passages 201 and 202 includes two check valves 211 and 212. On the upper end surface of the oil passage block 401, the heads of the four check valves 211 and 212 are arranged in the front-rear direction. In addition, a communication port 218 a is provided on the upper end surface of the oil passage block 401 between the second check valve 211 from the front and the third check valve 212 from the front, and is connected to the charge branch oil passage 219. The discharge side of the charge introduction oil passage 218 is connected.

Bypass oil passages 213 and 214 extending in parallel with the charge branch oil passage 219 are formed on the lower side in the oil passage block 401 so as to correspond to the closed oil passages 201 and 202. The straight traveling first oil passage 201a and the straight traveling second oil passage 201b are also communicated with each other by a straight traveling bypass oil passage 213. Further, the turning first oil passage 202a and the turning second oil passage 202b are also communicated with each other by a turning bypass oil passage 214. Bidirectional relief valves 215 and 216 are arranged at positions orthogonal to the respective closed oil passages 201 and 202 and the corresponding bypass oil passages 213 and 214. In the embodiment, the rectilinear-side bidirectional relief valve 215 is positioned at an orthogonal position between the rectilinear first oil passage 201a and the rectilinear bypass oil passage 213 in the rectilinear closed oil passage 201. The rectilinear bypass oil passage 213 is opened on the front end face side of the oil passage block 401, and the rectilinear bi-directional relief valve 215 is inserted rearward from the opening and attached. In addition, the turning-side bidirectional relief valve 216 is positioned at a position orthogonal to the turning first oil passage 202 a and the turning bypass oil passage 214 in the turning closed oil passage 202. The turning bypass oil passage 214 is opened on the rear end face side of the oil passage block 401, and the turning-side bidirectional relief valve 216 is inserted and attached through the opening. Therefore, as described above, each of the closed oil passages 201 and 202 includes one bidirectional relief valve 215 and 216, respectively.

If comprised in this way, since check valve 211,212 and bidirectional | two-way relief valve 215,216 will be separately arrange | positioned with respect to each oil-closing path 201,202, for example, it describes in patent document 1 Such an expensive check relief valve need not be used, and this point also contributes to a reduction in cost of the hydraulic transmission including the continuously variable transmission case and the oil passage block.

As shown in FIGS. 21 and 22, a surplus relief valve 220 that discharges surplus hydraulic fluid in the charge branch oil passage 219 is connected to one end side of the charge branch oil passage 219. The surplus relief valve 220 of the embodiment is connected between the check valve 212 for the turning second oil passage 202b in the charge branching oil passage 219 and the inlet portion of the turning servo oil passage 403, and inside the continuously variable transmission case 323. It is located. Accordingly, the excess hydraulic oil from the transmission charge pump 151 spills into the continuously variable transmission case 323 via the excess relief valve 220. Thereafter, it is returned to the mission case 63.

As shown in FIGS. 20 to 22, the front and rear end portions of the charge branch oil passage 219 are positioned below the charge branch oil passage 219 and extend in a direction perpendicular to the charge branch oil passage 219. It connects with each of the paths 402 and 403. The servo oil passages 402 and 403 are provided in the oil passage block 401 and the continuously variable transmission case 323, and the linear valve 203 and the swing valve in the hydraulic servo mechanisms 205 and 208 provided on the front and rear end surfaces of the continuously variable transmission case 323. It communicates with 206 ports. As a result, in the hydraulic servo mechanism 205, the hydraulic oil supplied from the charge introduction oil passage 218 to the oil passage block 401 is supplied to the straight valve 203 and the straight cylinder 204 through the charge branch oil passage 219 and the servo oil passage 402. . Similarly, in the hydraulic servo mechanism 208, hydraulic oil supplied from the charge introduction oil passage 218 to the oil passage block 401 is supplied to the swing valve 206 and the swing cylinder 207 through the charge branch oil passage 219 and the servo oil passage 403. .

1 traveling machine body 7 engine 63 mission case 64 straight hydraulic continuously variable transmission 70 swing hydraulic continuously variable transmission 200 hydraulic circuit 201 straight forward closed oil path 201a straight forward first oil path 201b straight forward second oil path 202 swivel closed oil path 202a One oil passage 202b, turning second oil passage 205, hydraulic servomechanism 208 for rectilinear speed change, hydraulic servomechanism for turning speed change (turning)
211, 212 Check valve 213, 214 Bypass oil passage 215, 216 Bidirectional relief valve 218 Charge introduction oil passage 219 Charge branch oil passage 220 Surplus relief valve 323 Stepless transmission case

Claims (3)

1. In a hydraulic transmission including a continuously variable transmission case incorporating a pair of hydraulic continuously variable transmissions formed by combining a hydraulic pump and a hydraulic motor, and an oil passage block attached to one side of the continuously variable transmission case,
   A hydraulic servo mechanism for operating each of the hydraulic continuously variable transmissions is arranged in the continuously variable transmission case so as to be distributed to both ends across the both hydraulic continuously variable transmissions,
   In the oil passage block, a closed loop oil passage for each of the hydraulic continuously variable transmissions and a charge oil passage connecting both the closed loop oil passages are formed,
   Servo oil passages connecting the charge oil passages and the respective hydraulic servo mechanisms are formed from the oil passage block toward the continuously variable transmission case so as to extend perpendicular to the charge oil passages and in parallel with each other. Yes,
   Hydraulic transmission.
2. In each of the closed loop oil passages, a bypass oil passage extending in parallel with the charge oil passage is orthogonal, a check valve is disposed at an orthogonal position between each of the closed loop oil passage and the charge oil passage, and each of the closed loop oil passages And a relief valve is arranged at a position orthogonal to the bypass oil passage,
   The hydraulic transmission according to claim 1.
3. A surplus relief valve that discharges surplus hydraulic fluid in the charge oil passage is connected to one end side of the charge oil passage.
   The hydraulic transmission according to claim 1 or 2.

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