JP5340753B2 - Traveling vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To simplify an operation system, and to improve operability, in a travel vehicle having transmissions 53 and 54 for a straight advance and turning for shifting motive power of an engine mounted on a traveling machine body, a straight advance operation tool to the transmission 53 for a straight advance, and a turning operation tool of the transmission 54 for turning. <P>SOLUTION: This travel vehicle has a control body rotatable around the mutually orthogonal turning axis and the shifting axis. While operating the transmission 54 for turning by the reciprocal rotational movement around the turning axis of the control body caused by operation of the turning operation tool, the transmission 53 for a straight advance is operated by the reciprocal rotational movement around the shifting axis of the control body caused by operation of the straight advance operation tool. The control body is built in a transmission case 18 for transmitting output from the respective transmissions 53 and 54 to right-left travel parts. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a traveling vehicle such as a farm work machine such as a combine machine or a special work machine such as a crane truck.

  Conventionally, a combine as a traveling vehicle is configured to transmit power from an engine mounted on a traveling body to left and right traveling crawlers via a straight transmission, a turning transmission, and a differential mechanism. ing.

  An example of a combine having such a configuration is disclosed in Patent Document 1. In the combine of Patent Document 1, the drive output amount of the straight transmission, that is, the straight traveling speed of the traveling machine body is adjusted according to the tilting operation amount of the main transmission lever provided in the control unit. If the main transmission lever is in the neutral position, the traveling aircraft will not go straight. Further, the drive output amount of the turning transmission, that is, the turning direction and turning speed of the traveling vehicle body are adjusted according to the turning direction and the turning operation amount of the steering handle disposed in front of the control seat in the control unit. Is done.

  In this case, the main transmission lever and the steering handle are linked and connected to the linear transmission and the turning transmission via a mechanical interlocking mechanism that uses many rods, arms, pivot pins, and the like. The mechanical interlocking mechanism of Patent Document 1 is built in a steering column disposed in front of a control seat in a control unit of a traveling machine body. Due to the action of the mechanical interlocking mechanism in the steering column, the combine of Patent Document 1 can be driven (controlled) at the same operation interval as that of a four-wheeled vehicle, although it is a crawler type.

JP 2000-177619 A

  However, in the combine of Patent Document 1, the mechanical interlocking mechanism uses a lot of long rods, arms, pivot pins, etc. and has a rather complicated structure, so the parts cost required for the mechanical interlocking mechanism increases. However, there was a problem that it did not meet the demand for cost reduction, which has been increasing in recent years. In addition, since the mechanical interlocking mechanism with a complicated structure is arranged in the steering column in front of the control seat, the space around the control seat tends to be narrowed, which is improved in view of the comfort during the combine operation. There was room for.

  The present invention further improves the above-described prior art, simplifies the structure for interlockingly connecting the operation means such as the main shift lever and each transmission as much as possible. Responding to the improvement of comfort is a technical issue.

According to a first aspect of the present invention, there is provided a linear travel and turning transmission that shifts the power of an engine mounted on a traveling machine body, a linear operation tool that controls a straight output of the linear transmission, and the turning transmission. The vehicle includes a turning operation tool that controls turning output, and includes a control body that can turn about a turning axis and a transmission axis that are orthogonal to each other, and the control associated with the operation of the turning operation tool. The turning transmission is actuated by forward / reverse rotation around the turning axis of the body, while the rectilinear advance is made by forward / reverse rotation of the control body around the transmission axis in accordance with the operation of the linear operation tool. The control body is built in a transmission case that transmits the output from each transmission to the left and right traveling units, and is operated by operating the turning operation tool. The horizontal swivel input shaft that moves Is built into Nkesu, the control body, the so as to rotate the tilt to shift about an axis perpendicular to the pivot axis of the pivot input shaft, while provided in the swivel input shaft, the revolving input The shaft is provided with a slider that rotates together with the pivot axis so as to be able to reciprocate along the pivot axis. The linear operation tool and the slider can be operated by operating the linear operation tool. The slider and the control body are connected so that the control body tilts and rotates about the speed change axis in conjunction with the reciprocation of the slider. That's it.

According to a second aspect of the present invention, in the combine according to the first aspect , the box portion that houses the control body, the turning input shaft and the slider in the transmission case is higher than the upper surfaces of the left and right traveling portions. It is arranged at the position.

  According to the present invention, the control body is provided that can be rotated about the rotation axis and the transmission axis that are orthogonal to each other, and for turning by forward and reverse rotation of the control body around the rotation axis in accordance with the operation of the turning operation tool. While the transmission is operated, the linear transmission is operated by forward / reverse rotation of the control body around the transmission axis along with the operation of the linear operation tool. For this reason, “when the turning operation tool is turned to a position other than neutral in a state where the straight operation tool is tilted to a position other than neutral, the larger the turning operation amount is, the smaller the turning aircraft body is to the left or The operation of “turning to the right” can be executed by both the forward / reverse rotation around the turning axis and the forward / reverse rotation around the speed change axis in the control body.

  In other words, the control body has a turning steering function for operating the turning transmission in conjunction with the operation of the turning operation tool, and a traveling shift for operating the linear transmission in conjunction with the operation of the linear operation tool. It has both functions. Therefore, compared with the structure of the operation system using many long rods, arms, pivot pins, and the like as in Patent Document 1, the number of component parts of the operation system according to the present invention is smaller. It is possible to avoid variations in the operation system due to the precise processing accuracy and assembly accuracy. Moreover, the adjustment work etc. when assembling the operation system of the present invention can be simplified as compared with the conventional one. In addition, since the control body is built in the transmission case, it is possible to reduce or eliminate the steering column that supports the turning operation tool, and to secure a wide space around the control section.

It is a side view of a combine. It is a top view of a combine. It is a skeleton figure of a power transmission system. It is a skeleton figure inside a mission case. It is front explanatory drawing which shows the arrangement | positioning aspect of a steering box. It is a principal part enlarged front view of FIG. It is plane explanatory drawing which shows the arrangement | positioning aspect of a steering box. It is a principal part enlarged plan view of FIG. It is explanatory drawing which shows a mechanical interlocking mechanism typically. It is a top view of a steering box. It is a XI-XI view side view of FIG. It is XII-XII view side surface sectional drawing of FIG. FIG. 13 is a plan sectional view taken along line XIII-XIII in FIGS. 11 and 12. It is a XIV-XIV view plane sectional view of Drawing 11 and Drawing 12. FIG. 13 is a plan sectional view taken along line XV-XV in FIGS. 11 and 12. FIG. 13 is a side sectional view taken along line XVI-XVI in FIGS. 11 and 12. FIG. 14 is a side sectional view taken along line XVII-XVII in FIGS. 10 and 13. It is a principal part enlarged view of FIG. It is a principal part enlarged view of FIG.

  Hereinafter, an embodiment embodying the present invention will be described with reference to the drawings when applied to a combine as a traveling vehicle.

(1). Schematic structure of combine First, the schematic structure of the combine in the embodiment will be described with reference to FIGS. 1 and 2.

  A combine which is an example of a traveling vehicle includes a traveling machine body 1 supported by a pair of left and right traveling crawlers 2 and 2 as a traveling unit. At the front part of the traveling machine body 1, a reaping device 3 that takes in a planted cereal culm (uncut cereal culm) in the field is harvested by a single-acting hydraulic cylinder 4 so as to be adjustable up and down.

  The traveling machine body 1 is equipped with a threshing device 5 with a feed chain 6 and a grain tank 7 for storing grains after threshing in a side-by-side manner. In this case, the threshing device 5 is disposed on the left side in the traveling direction of the traveling machine body 1, and the Glen tank 7 is disposed on the right side in the traveling direction of the traveling machine body 1. A discharge auger 8 is provided at the rear of the traveling machine body 1 so as to be able to turn. The grain in the Glen tank 7 is carried out from the tip culling port of the discharge auger 8 to, for example, a truck bed or a container.

  In a control unit 9 provided between the reaping device 3 and the Glen tank 7, a steering handle 10 as a turning operation tool for changing a turning direction and a turning speed of the traveling machine body 1 and a control seated by an operator. A seat 11 and the like are arranged. A side column 12 disposed on one side of the control seat 11 has predetermined outputs of the main transmission lever 13 as a linear operation tool for performing a speed change operation of the traveling machine body 1 and the output and rotation speed of a hydraulic continuously variable transmission 50 described later. A sub-transmission lever 14, a mowing device 3 and a clutch lever 15 for power disconnection operation to the threshing device 5 are provided.

  The main speed change lever 13 is used to move the traveling machine body 1 forward, stop, reverse, and change its vehicle speed steplessly. The sub-shift lever 14 changes the sub-transmission mechanism 51 in the mission case 18 to be described later according to the working state, and the output and the rotational speed of the straight-travel HST mechanism 53 to be described later are set to a low speed and a high speed 2 across the neutral. This is for setting and maintaining the gear positions.

  The clutch lever 15 serves as a single power transmission lever for the reaping device 3 and a power transmission operation lever for the threshing device 5, and is tilted back and forth along the crank groove of the side column 12. It is configured to be possible. When the clutch lever 15 is tilted to the front end of the crank groove, both the reaping clutch 89 and the threshing clutch 91 (see FIG. 3) are turned off, and when tilted to the middle part of the crank groove, only the threshing clutch 91 is turned on. When the crank groove is tilted to the rear end, both clutches 89 and 91 are engaged.

  An engine 17 as a power source is disposed below the control unit 9. A mission case 18 is disposed in front of the engine 17 and between the left and right traveling crawlers 2 for appropriately shifting the power from the engine 17 and transmitting it to the left and right traveling crawlers 2. A diesel engine is employed as the engine 17 of the embodiment.

  The reaping device 3 includes a clipper-type cutting blade device 19, a culm pulling device 20 for four strips, a culm conveying device 21, and a weeding body 22. The cutting blade device 19 is disposed below the cutting frame 41 (see FIG. 1) that constitutes the framework of the cutting device 3. The grain raising apparatus 20 is disposed above the cutting frame 41. The corn straw transporting device 21 is disposed between the corn straw pulling device 20 and the feed start end of the feed chain 6. The weed body 22 is provided in front of the lower part of the grain raising device 20. The traveling machine body 1 continuously cuts uncut cereal grains in the field by driving the reaping device 3 while driving the left and right traveling crawlers 2 by the engine 17 and moving in the field.

  The threshing device 5 includes a handling cylinder 23 for threshing the harvested cereal, a swing sorting mechanism 24 and a wind sorting mechanism 25 disposed below the handling cylinder 23, and a threshing taken out from the rear part of the handling cylinder 23. A dust-feeding port processing cylinder 26 for reprocessing an object is provided. The handling cylinder 23 is arranged in the handling chamber of the threshing device 5. The swing sorting mechanism 24 is for swinging and sorting the cereals threshed by the handling cylinder 23, and the wind sorting mechanism 25 is for wind sorting the threshing.

  The stock source side of the harvested cereal meal sent from the harvesting device 3 is inherited by the feed chain 6. Then, the tip side of the harvested cereal meal is carried into the threshing device 5 and threshed by the handling cylinder 23. In addition, the rotating shaft 95 (refer FIG. 3) of the handling cylinder 23 is extended along the feed direction (the advancing direction of the traveling body 1) of the harvested cereal meal by the feed chain 6.

  In the lower part of the threshing device 5, there are a first receiving bowl 27 where most of the grains selected from the two sorting mechanisms 24, 25 are collected, a grain with a branch stem, a grain of ears, etc. There is provided a second receiving bowl 28 where second things gather. The two receiving rods 27 and 28 of the embodiment are horizontally provided above the rear portion of the traveling crawler 2 in a side view in order of the first receiving rod 27 and the second receiving rod 28 from the front side in the traveling direction of the traveling machine body 1.

  The first thing such as the fine grains collected in the first receiving bowl 27 through the sorting by both sorting mechanisms 24 and 25 is the first conveyor 29 in the first receiving bowl 27 and the cereal in the milling cylinder 31. It is sent to the Glen tank 7 via the conveyor 32 (see FIG. 3).

  Second items such as grain with branch stems are collected in the second receiving rod 28 behind the first receiving rod 27, and from here, the second conveyor 30 in the second receiving rod 28 and the reduction in the reducing cylinder 33 are collected. It is sent to the second processing cylinder 35 via the conveyor 34 (see FIG. 3). And after the second thing is rethreshed in the second treatment cylinder 35, it is returned to the threshing apparatus 5 and reselected. The sawdust is sucked into the dust exhaust fan 36 and discharged out of the machine from a discharge port (not shown) provided in the rear part of the threshing device 5.

  A waste chain 37 is disposed on the rear side (feed end side) of the feed chain 6. The waste (granulated soot) inherited from the rear end of the feed chain 6 to the waste chain 37 is discharged to the rear of the traveling machine body 1 in a long state, or the waste cutter located behind the threshing device 5. After being cut to a suitable length at 38, it is discharged to the rear of the traveling machine body 1.

(2). Next, the power transmission system of the combine will be described with reference to FIGS. 3 and 4.

  One of the power from the engine 17 is branched and transmitted in the two directions of the traveling crawler 2 (reaping device 3) and the threshing device 5. Other power from the engine 17 is transmitted to the discharge auger 8. The branching power from the engine 17 toward the traveling crawler 2 is once transmitted to the HST mechanisms 53 and 54 (details will be described later) of the transmission case 18 via the pulley / belt transmission system and the traveling clutch 88. In this case, the branch power from the engine 17 is appropriately shifted by the HST mechanisms 53, 54, etc. of the mission case 18, and is transmitted to the left and right drive wheels 90 via the drive output shaft 77 protruding outward from the left and right. It is configured to output.

  The transmission case 18 includes a straight traveling HST mechanism 53 (transmission for straight travel) including a first hydraulic pump 55 and a first hydraulic motor 56, and a turning HST mechanism 54 (including a second hydraulic pump 57 and a second hydraulic motor 58). A turning transmission), a sub-transmission mechanism 51 having a plurality of shift stages, and a differential mechanism 52 having a pair of left and right planetary gear mechanisms 68 and the like (see FIG. 4).

  The power directed from the output shaft 49 of the engine 17 to the hydraulic continuously variable transmission 50 via the travel clutch 88 is transmitted to the first pump shaft 59a protruding from the first hydraulic pump 55. In the straight traveling HST mechanism 53, hydraulic oil is appropriately fed from the first hydraulic pump 55 toward the first hydraulic motor 56 by the power transmitted to the first pump shaft 59a. The first pump shaft 59a and the second pump shaft 59b protruding from the second hydraulic pump 57 are connected to each other through a pulley / belt transmission system so that power can be transmitted. In the turning HST mechanism 54, hydraulic oil is appropriately fed from the second hydraulic pump 57 toward the second hydraulic motor 58 by the power transmitted to the second pump shaft 59b.

  The straight-travel HST mechanism 53 changes and adjusts the inclination angle of the rotary swash plate in the first hydraulic pump 55 in accordance with the operation amount of the main transmission lever 13 and the steering handle 10 disposed in the control unit 9. By changing the discharge direction and discharge amount of the hydraulic oil to the hydraulic motor 56, the rotation direction and the rotation speed of the linear motor shaft 60 protruding from the first hydraulic motor 56 are arbitrarily adjusted.

  The rotational power of the linear motor shaft 60 is transmitted to the auxiliary transmission mechanism 51 via the linear transmission gear mechanism 62. The sub-transmission mechanism 51 has an adjustment range of the rotational power (rotation direction and number of rotations) from the linear motor shaft 60 by operating the sub-transmission lever 14 disposed in the control unit 9. It is for switching to a stage gear. A neutral position (a position where the output of the sub-shift is 0 (zero)) is provided between the low-speed and medium-speed of the sub-shift and between the medium and high-speed.

  An auxiliary transmission shaft 51a on the upstream side of the auxiliary transmission mechanism 51 is connected to a cutting PTO shaft 64 projecting from the transmission case 18 via a one-way clutch 63 and the like so as to be able to transmit power. The power transmitted to the reaping PTO shaft 64 is actuated by the engagement operation of the reaping clutch 89 via the reaping input shaft 43 in the horizontally long reaping input pipe 42 (see FIG. 1) constituting the framework of the reaping device 3. It is transmitted to each device 19-21 of the reaping device 3. For this reason, each of the devices 19 to 21 of the reaping device 3 is driven at the vehicle speed synchronization speed. A parking brake 66 such as a wet multi-plate disk is provided on the parking brake shaft 65 on the downstream side of the auxiliary transmission mechanism 51.

  The rotational power transmitted from the sub transmission shaft 51 a of the sub transmission mechanism 51 to the parking brake shaft 65 is transmitted from the sub transmission output gear 67 fixed to the parking brake shaft 65 to the differential mechanism 52. The differential mechanism 52 includes a pair of planetary gear mechanisms 68 arranged symmetrically. The auxiliary transmission output gear 67 of the parking brake shaft 65 is engaged with an intermediate gear 70 attached to a relay shaft 69 between the planetary gear mechanism 68 and the parking brake shaft 65, and the intermediate gear 70 is fixed to the sun gear shaft 75. Is engaged with the center gear 76 (details will be described later).

  Each of the left and right planetary gear mechanisms 68 includes one sun gear 71, a plurality of planetary gears 72 that mesh with the outer periphery of the sun gear 71, a ring gear 73 that meshes with the outer periphery of these planetary gears 72, and a plurality of planetary gears 72 on the same radius. And a carrier 74 that is rotatably supported by the shaft. The carriers 74 of the left and right planetary gear mechanisms 68 are arranged so as to oppose each other at an appropriate interval on the same axis. A center gear 76 that meshes with the intermediate gear 70 is fixed to the central portion of the sun gear shaft 75 located between the left and right planetary gear mechanisms 68. Sun gears 71 are fixed to both sides of the sun gear shaft 75 with the center gear 76 interposed therebetween.

  The left and right ring gears 73 having inner teeth on the inner peripheral surface and outer teeth on the outer peripheral surface are arranged concentrically on the sun gear shaft 75 with the inner teeth meshing with the plurality of planetary gears 72. . Each ring gear 73 is rotatably supported by a drive output shaft 77 that protrudes left and right outward from the outer surface of the carrier 74. A drive wheel 90 is attached to the tip of the drive output shaft 77. Accordingly, the rotational power transmitted from the subtransmission mechanism 51 to the left and right planetary gear mechanisms 68 is transmitted from the drive output shaft 77 of each carrier 74 to the left and right drive wheels 90 at the same rotational speed in the same direction, so The crawler 2 is driven.

  In the turning HST mechanism 54, the inclination angle of the rotary swash plate in the second hydraulic pump 57 is changed and adjusted according to the turning operation amount of the steering handle 10, and the hydraulic oil is discharged to the second hydraulic motor 58. By changing the direction and the discharge amount, the rotational direction and the rotational speed of the turning motor shaft 61 protruding from the second hydraulic motor 58 are arbitrarily adjusted.

  In the embodiment, a steering brake shaft 78 having a steering brake 79, a steering clutch shaft 80 having a steering clutch 81, and left and right input gears 82 that are always meshed with the external teeth of the left and right ring gears 73 in the transmission case 18. , 83. A steering clutch shaft 80 is connected to a turning motor shaft 61 of the second hydraulic motor 58 via a steering brake shaft 78 and a steering clutch 81. A right input gear 83 is connected to the steering clutch shaft 80 via a normal rotation gear 84, and a left input gear 82 is connected via a normal rotation gear 84 and a reverse rotation gear 85.

  The rotational power of the turning motor shaft 68 is transmitted to the steering clutch shaft 80 via the steering brake shaft 78 and the steering clutch 81, and the rotational power transmitted to the steering clutch shaft 80 is transmitted to the forward rotation gear 84 and The rotation is transmitted from the reverse gear 85 to the corresponding left and right input gear mechanisms 82 and 83.

  When the subtransmission mechanism 51 is neutral, the steering brake 79 is engaged, and the steering clutch 64 is disengaged, power transmission from the second hydraulic motor 58 to the left and right planetary gear mechanisms 68 is blocked. . When the steering brake 79 is turned off and the steering clutch 64 is engaged at the time of sub-shift output other than neutral, the rotational power of the second hydraulic motor 58 is transmitted through the forward rotation gear 84 and the right input gear 83. Is transmitted to the right ring gear 73, while being transmitted to the left ring gear 73 via the forward rotation gear 84, the reverse rotation gear 85 and the left input gear 82. As a result, when the second hydraulic motor 58 is forwardly rotated (reversely rotated), the left ring gear 73 is reversely rotated (forward) and the right ring gear 73 is normally rotated (reversely rotated) at the same number of rotations in the opposite directions. Become.

  As can be seen from the above configuration, the shift output from each of the motor shafts 60 and 61 is transmitted to the drive wheels 90 of the left and right traveling crawlers 2 via the auxiliary transmission mechanism 51 and the differential mechanism 52, respectively. As a result, the vehicle speed (traveling speed) and traveling direction of the traveling machine body 1 are determined.

  That is, when the first hydraulic motor 56 is driven in a state where the second hydraulic motor 58 is stopped and the left and right ring gears 73 are stationary, the rotation output from the linear motor shaft 60 is the same from the center gear 76 to the left and right sun gears 71. The left and right traveling crawlers 2 are driven at the same rotational speed in the same direction via the planetary gears 72 and the carriers 74 of both planetary gear mechanisms 68, and the traveling machine body 1 travels straight.

  Conversely, when the second hydraulic motor 58 is driven while the first hydraulic motor 56 is stopped and the left and right sun gears 71 are stationary, the left planetary gear mechanism 68 is driven by the rotational power from the turning motor shaft 61. The right planetary gear mechanism 68 rotates in the reverse or forward direction. Then, one of the drive wheels 90 of the left and right traveling crawlers 2 rotates forward and the other rotates backward, so that the traveling machine body 1 spin-turns on the spot.

  Further, when the second hydraulic motor 58 is driven while the first hydraulic motor 56 is driven, a difference occurs between the speeds of the left and right traveling crawlers 2, and the traveling machine body 1 moves forward or backward while turning larger than the spin turn turning radius. Will turn left or right. The turning radius at this time is determined according to the speed difference between the left and right traveling crawlers 2.

  Now, as shown in FIG. 3, the branching power toward the threshing device 5 among the power from the engine 17 is transmitted to the threshing input shaft 92 via the threshing clutch 91. A part of the power transmitted to the threshing input shaft 92 is transmitted to the rotating shaft 94 of the dust feeding port processing cylinder 26, the rotating shaft 95 of the handling cylinder 23, and the waste chain 37 via the threshing drive mechanism 93. The

  In addition, from the threshing input shaft 92, through the pulley and the belt transmission system, the Kara fan shaft 96 of the wind sorting mechanism 25, the first conveyor 29 and the cereal conveyor 32, the second conveyor 30 and the reduction conveyor 34, and the second processing. Power is also transmitted to the barrel 35, the swing shaft 97 of the swing selection mechanism 24, the dust discharge shaft 98 of the dust exhaust fan 36, and the waste cutter 38. The branching power via the dust removal shaft 98 is transmitted to the feed chain 6 via the feed chain clutch 99 and the feed chain shaft 100.

  The power from the threshing input shaft 92 can also be transmitted to the reaping input shaft 43 via the pouring clutch 101 that transmits a constant rotational force to the reaping device 3. That is, by directly transmitting the power from the engine 17 to the reaping device 3 without passing through the mission case 18, the reaping device 3 can be forcibly driven at a constant high speed regardless of whether the vehicle speed is fast or slow. It is configured.

  The power directed from the engine 17 to the discharge auger 8 is transmitted to the bottom conveyor 104 in the Glen tank 7 and the vertical conveyor 105 in the vertical auger cylinder in the discharge auger 8 through the Glen input gear mechanism 102 and the auger clutch 103 for power transmission. Then, the power is transmitted to the discharge conveyor 107 in the horizontal auger cylinder of the discharge auger 8 through the transfer screw 106.

(3). Structure for Shift Steering Control Next, a structure for shift steering control for adjusting the vehicle speed and traveling direction of the traveling machine body 1 will be described with reference to FIGS. 1, 2, and 5 to 17.

  A steering input shaft 112 extending vertically is rotatably supported in front of the control seat 11 in the step floor member 111 constituting the bottom surface of the control unit 9. The lower end portion of the handle shaft 113 is connected to the upper end portion of the steering input shaft 112 via a universal joint 114 (see FIG. 9). A round steering handle 10 as a turning operation tool is attached to the upper end portion of the handle shaft 113. By changing the attachment position of the steering handle 10 in the front-rear direction by the bending operation of the universal joint 114, the steering handle 10 can be adjusted to a position corresponding to the physique of the operator.

  As schematically shown in FIG. 9, a main driving bevel gear 116 is fixed to the lower end portion of the steering input shaft 112. On the other hand, a driven bevel gear 117 is fixed to the input relay shaft 115 protruding horizontally from the mission case 18 (direction toward the control unit 9). By engaging the main bevel gear 116 and the driven bevel gear 117, the steering input shaft 112 and the input relay shaft 115 are coupled so as to transmit power. Accordingly, when the steering handle 10 is rotated, the main driving bevel gear 116 is rotated via the steering shaft 113 and the steering input shaft 112, and the driven bevel gear 117 and the input relay shaft 115 are rotated in conjunction therewith. Will do.

  As shown in FIGS. 5 to 8, a mechanical interlocking mechanism 121 for the main transmission lever 13 and the steering handle 10 is built in the transmission case 18 in front of the engine 17 and between the left and right traveling crawlers 2. . As will be described in detail later, the main transmission lever 13 and the steering handle 10 are interlocked and connected to output control units of the HST mechanisms 53 and 54 via a mechanical interlocking mechanism 121. In the embodiment, the straight traveling HST mechanism 53 and the turning HST mechanism 54 are arranged side by side on the upper side of the mission case 18 with the turning forward and the straight traveling backward. And the box part 120 is projected horizontally outward so as to be back-to-back with the turning HST mechanism 54, and the mechanical interlocking mechanism 121 is arranged in the box part 120. As shown in FIG. 5, the lower end of the box portion 120 is at a height position higher than the upper surface of the left and right traveling crawler 2 by H. In other words, the box part 120 is disposed at a height position higher than the upper surface of the left and right traveling crawler 2.

  The box portion 120 is formed of a die cast or cast upper box portion 120a and a die cast or cast lower box portion 120b on a plane A (see FIG. 11) perpendicular to the swing axis P of the swing input shaft 122. It has a split structure. The lower box portion 120b is integrally formed on the back side of the turning HST mechanism 54 in the mission case 18. The upper and lower box portions 120a and 120b are detachably coupled with a plurality of bolts (not shown) with a sealing gasket (not shown) sandwiched therebetween. The hydraulic oil in the mission case 18 circulates inside the box part 120. The hydraulic oil is used for various hydraulic devices in the combine (for example, a hydraulic cylinder 4 that moves the reaping device 3 up and down), or lubricates the engine and the transmission case. In this case, the mechanical interlocking mechanism 121 is lubricated with the hydraulic oil in the box portion 120.

The mechanical interlocking mechanism 121 is
1. When the steering handle 10 is rotated to a position other than neutral (turning output from the turning HST mechanism 54) in a state where the main transmission lever 13 is tilted to a position other than neutral (straight-running output from the straight HST mechanism 53). As the turning operation amount of the steering handle 10 increases, the traveling vehicle body 1 turns left or right with a small turning radius, and the vehicle speed of the traveling vehicle body 1 (turning speed when moving forward or backward) decreases as the turning radius decreases. Slow down,
2. Even when the main transmission lever 13 is tilted in either the forward or backward direction, the turning operation direction of the steering handle 10 matches the turning direction of the traveling machine body 1 (the steering handle 10 is turned to the left). If it is turned, the traveling machine body 1 turns to the left, and if the steering handle 10 is turned to the right, the traveling machine body 1 turns to the right)
3. When the main transmission lever 13 is in the neutral position (the straight output from the straight HST mechanism 53 is zero), the steering handle 10 does not function (the turning output of the turning HST mechanism 54 is maintained at zero). ,
In order to execute various operations, the operation force from the main transmission lever 13 and the steering handle 10 is appropriately converted, and the transmission output shaft 136 and the turning output shaft 164 projecting outward from the side surface of the box portion 120 (details) Is configured to be transmitted to a later described).

  As shown in FIG. 9 to FIG. 17, the mechanical interlocking mechanism 121 includes a horizontal lateral turning input shaft 122 that is pivotally supported at both ends in the box portion 120. The input relay shaft 115 and the turning input shaft 122 extend in parallel with each other. By engaging the spur gear 123 fixed to the tip of the swivel input shaft 122 and the spur gear 118 fixed to the end of the input relay shaft 115 in the box portion 120, the input relay shaft 115 and the swivel input are engaged. The shaft 122 is connected so that power can be transmitted. Accordingly, the turning operation force of the steering handle 10 is transmitted to the turning input shaft 122 via the input relay shaft 115.

  A slider 125 is fitted on the front end side of the turning input shaft 122 so as to be slidable back and forth via a ball-type key 127 and the like. A holder member 126 is fitted to the base end side of the turning input shaft 122 so as not to rotate and slide. The slider 125 is configured to freely slide along the turning axis P direction of the turning input shaft 122. The slider 125 is configured to rotate around the turning axis P together with the turning input shaft 122.

  A winding spring 128 is fitted on a portion of the turning input shaft 122 closer to the proximal end than the holder member 126. The start end 128 a and the end end 128 b of the winding spring 128 sandwich both the distal-end convex pin 129 fixed to the box portion 120 and the proximal-end convex pin 130 fixed to the holder member 126. . The winding spring 128 constantly urges the holder member 126 and, consequently, the steering handle 10 in a direction to return it from the position rotated left and right to the neutral position (straight traveling position). That is, the turning operation of the steering handle 10 in the left-right direction is performed against the elasticity of the winding spring 128. Then, the turning operation to the original neutral position (straight running position) uses the elastic restoring force of the winding spring 128.

  The rotatable range of the holder member 126 is regulated within the range of the maximum cutting angles θ1 and θ2 from the neutral position to the left and right (for example, θ1 = 67.5 °, θ2 = 67.5 °, FIG. 13 and FIG. 15). Then, the rotatable range of the steering handle 10 is set to an angle range of about 135 ° to the left and right with respect to the neutral position due to the gear ratio of the spur gears 118 and 123.

  A ring-shaped control body 131 that surrounds the periphery of the turning input shaft 122 is disposed on the base end side in the box portion 120 in a plan view as viewed from the turning axis P direction of the turning input shaft 122. A pair of inward boss portions 132 are formed on a portion of the inner surface of the control body 131 on the speed change axis S that passes through the rotation center of the turning input shaft 122 and is orthogonal to the turning axis P of the turning input shaft 122 in plan view. Has been. The pair of inward bosses 132 are pivotally attached to the holder member 126 by a screw shaft 133. The control body 131 is supported via a holder member 126 so as to be rotatable around the transmission axis S (screw shaft 133). Therefore, the control body 131 is rotatable around two axes P and S orthogonal to each other.

  A circular cam 134 extending in the circumferential direction around the turning axis P of the turning input shaft 122 is formed on the outer peripheral portion of the control body 131. The circular cam 134 is formed with a cam groove 134a extending over the entire circumference.

  On the front end side in the box portion 120, a laterally oriented main transmission lever input shaft 135 is disposed on one of both sides across the turning input shaft 122. On the other side of the box portion 120, a lateral transmission input shaft 136 is disposed. The main transmission lever input shaft 135 and the transmission input shaft 136 extend in parallel with each other in a plan view and are rotatably supported by the box portion 120. The distal ends of the main transmission lever input shaft 135 and the transmission input shaft 136 protrude outward from the side surface of the box portion 120.

  As shown in FIGS. 5 to 8, the main transmission lever input shaft 135 of the embodiment protrudes upward from the upper side surface of the box portion 120. A main transmission arm 137 is fixed to the tip (protruding end) of the main transmission lever input shaft 135. The main transmission lever 13 on the side column 12 is connected to the main transmission arm 137 via interlocking connection means 138 such as a rod. The main transmission lever input shaft 135 is configured to rotate by a forward / backward tilt operation of the main transmission lever 13.

  Further, the transmission output shaft 136 also protrudes upward from the upper surface of the box portion 120. A shift output arm 139 is fixed to the tip (projecting end) of the shift output shaft 136. The speed change output arm 139 is interlocked and connected to a rectilinear control shaft 149 protruding upward from the rectilinear HST mechanism 53 via a rectilinear relay rod 140. The rectilinear control shaft 149 is configured to rotate via the rectilinear relay rod 140 by the rotation of the speed change output shaft 136. In the embodiment, one end portion of the straight relay rod 140 is pivotally attached to the speed change output arm 139 of the speed change output shaft 136 via a vertical pivot pin. The other end of the rectilinear relay rod 140 is pivotally attached to a rectilinear operation arm 148 fixed to the rectilinear control shaft 149 via a vertical pivot pin.

  The rectilinear control shaft 149 is for adjusting the inclination angle (swash plate angle) of the rotary swash plate of the first hydraulic pump 55 in the rectilinear HST mechanism 53, and an output for adjusting the shift output of the rectilinear HST mechanism 53. It will function as a control unit. In other words, by adjusting the swash plate angle of the first hydraulic pump 55 by forward / reverse rotation of the linear advance control shaft 149, the rotational speed control or forward / reverse switching of the first hydraulic motor 56 is executed, and the traveling speed (vehicle speed) is increased. Stepless change and forward / reverse switching are performed.

  A pair of main transmission fork arms 151 are fixed to a portion of the main transmission lever input shaft 135 in the box portion 120. A ball bearing 152 provided at the tip of the main transmission fork arm 151 is fitted into and engaged with an annular groove 125 a formed on the outer periphery of the slider 125. For this reason, the slider 125 reciprocates along the turning input shaft 122 by the rotation of the main transmission lever input shaft 135 (the rotation operation of the main transmission lever 13). That is, when the main transmission lever 13 is in the neutral position, the slider 125 is located at a position indicated by a solid line in FIG. By rotating the main transmission lever 13 in the front-rear direction from the neutral position, the slider 125 slides back and forth.

  Further, the slider 125 and the control body 131 are connected by a swing link 153 having pins 154 at both ends. When the main transmission lever 13 is in the neutral position, the slider 125 does not move up and down. The control body 131 remains in the neutral position in the horizontal position and does not tilt and rotate. When the main transmission lever 13 is rotated forward or backward from the neutral position, the slider 125 reciprocates along the turning input shaft 122. As the slider 125 slides back and forth, the control body 131 tilts and rotates around the transmission axis S around the screw shaft 133. The control body 131 tilts and rotates within the range of angles α1 and α2 as appropriate in the vertical direction across the horizontal posture (see FIG. 16).

  An intermediate shaft 155, which is an example of a straight conversion shaft, is supported in the box portion 120 in parallel with the speed change output shaft 136. Both end portions of the intermediate shaft 155 protrude inside and outside the box portion 120. As will be described in detail later, the amount of rotation of the control body 131 around the transmission axis S is converted into a control amount of the straight traveling HST mechanism 53 via the intermediate shaft 155.

  A straight link 156 is provided at the inner end of the intermediate shaft 155 so as to freely rotate in a direction along the turning axis P. A shift slider member 157 is provided in a portion of the straight link 156 on the orthogonal axis W that passes through the rotation center of the turning input shaft 122 in a plan view and extends at a right angle to the speed change axis S. The shifting slider member 157 is supported by the rectilinear link 156 so as to be rotatable about the orthogonal axis W. The shifting slider member 157 is engaged with the circular cam 134 so as to be slidable in the circumferential direction.

  As shown in FIG. 18, the speed change slider member 157 includes a shaft portion 157 a that is rotatably supported by a straight link 156 by a ball bearing 157 b, and a sphere 157 c that is integrally provided at the tip of the shaft portion 157 a. It is comprised by. In the embodiment, the spherical body 157c of the shifting slider member 157 is inserted into the cam groove 134a of the circular cam 134 so as to be slidable and rotatable.

  The straight link 156 is connected to the distal end side of a speed change output link 158 rotatably connected to the speed change output shaft 136 via a connection link 159. When the circular cam 134 is tilted and rotated around the transmission axis S, the linear link 156 is configured to rotate about the axis of the intermediate shaft 155 via the transmission slider member 157. For this reason, the rectilinear link 156 and the shift output link 158 reciprocately rotate in conjunction with the tilt rotation of the control body 131 around the shift axis S.

  A base end of the non-decelerating arm 160 is rotatably fitted to the speed change output shaft 136. A pin 161 provided at the front end of the main transmission fork arm 151 is fitted into and engaged with a long hole 160a formed at the front end of the non-deceleration arm 160. For this reason, the non-decelerating arm 160 is configured to rotate in conjunction with the reciprocating rotation of the main transmission fork arm 151 (see FIG. 17).

  Further, a switching member 162 is provided at a portion of the transmission output shaft 136 between the transmission output link 158 and the non-deceleration arm 160. The switching member 162 is supported on the transmission output shaft 136 so as to be slidable in the axial direction thereof. By manually operating the switching member 162 and selectively selecting either the speed change output link 158 or the non-deceleration arm 160, the speed change output link 158 or the non-deceleration arm 160 is connected via the switching member 162. Are coupled to the transmission output shaft 136 so as to rotate integrally.

  As shown in FIG. 14, the switching member 162 is slid along the transmission output shaft 136 by the switching operation mechanism 169, so that the pin 163 provided on the switching member 162 is connected to the transmission output link 158 or the non-deceleration arm 160. Engage. Such a pin 163 engagement selectively switches between a turning deceleration state in which the transmission output link 136 is coupled to the transmission output shaft 136 and a turning non-deceleration state in which the non-deceleration arm 160 is coupled to the transmission output shaft 136. It is possible.

  As a result, in a harvesting operation where the amount of settlement of the traveling crawler 2 is small on the road or in a dry paddy field, when switching to the turning deceleration state, the center of the traveling machine body 1 (the center between the left and right traveling crawlers 2 is proportional to the turning radius. ) Can be decelerated. For example, the moving speed of the traveling machine 1 can be automatically reduced in proportion to the turning radius of the traveling machine 1 becoming smaller. That is, when the traveling machine body 1 turns in the state of switching to the turning deceleration state, the traveling crawler 2 on the inner side of the turning is in proportion to the turning radius while maintaining the moving speed of the traveling crawler 2 on the outer side of the turning at a substantially straight traveling speed. The moving speed is decelerated and the course is changed. Accordingly, it is possible to reduce the side slip of the traveling crawler 2 on the headland in the field.

  On the other hand, in a harvesting operation where the traveling crawler 2 has a large amount of sinking in a wet field or the like, the center of the traveling machine body 1 (the center between the left and right traveling crawlers) is switched regardless of the turning radius of the traveling machine body 1 when switching to the turning non-decelerated state. The moving speed is maintained at a substantially straight traveling speed. For example, the moving speed of the traveling crawler 2 on the outer side of the turning is increased as the turning radius of the traveling machine body 1 becomes smaller with reference to the straight traveling speed. That is, when switching to the turning non-deceleration state, the traveling speed of the traveling crawler 2 inside the turning can be reduced, the propulsive force of the traveling machine body 1 can be secured, and the turning performance in a wet paddy field that can easily slip can be improved. . When the traveling crawler 2 sinks a large amount, the traveling speed of the traveling machine body 1 is slowed down. Therefore, even if the traveling speed of the traveling crawler 2 on the outer side of the turn is significantly increased as compared to the straight traveling direction, The moving speed of the traveling crawler 2 does not become too fast.

  The switching operation mechanism 169 is configured as described below. That is, as shown in FIGS. 14 and 16, a switching operation shaft 170 extending parallel to the speed change output shaft 136 is supported on the box portion 120 so as to be slidable and rotatable. A switching plate 171 fixed to the switching operation shaft 170 is fitted and engaged with an annular groove 172 formed in the switching member 162. One end portion of the switching operation shaft 170 protrudes outside the box portion 120. A handle 173 is provided at the protruding end of the switching operation shaft 170.

  By holding the handle 173 and sliding the switching operation shaft 170 in the axial direction, the switching operation between the turning deceleration state and the turning non-deceleration state described above can be performed from the outside of the box portion 120. The switching operation shaft 170 is provided with a ball clutch 174. The ball clutch 174 holds the switching operation shaft 170 at a position corresponding to the turning deceleration state and a position corresponding to the turning non-deceleration state.

  A turning output shaft 164 serving as a turning conversion shaft extending in a direction orthogonal to the speed change output shaft 136 is supported in the box portion 120. Both end portions of the turning output shaft 164 protrude inside and outside the box portion 120. The outer end portion of the turning output shaft 164 protrudes rearward from the rear side surface of the box portion 120. The amount of rotation of the control body 131 around the turning axis P is converted into a control amount of the turning HST mechanism 54. The base end of the turning link 165 is fixed to the end of the turning output shaft 164 in the box portion 120. A turning slider member 166 is provided on a portion of the turning link 165 on the transmission axis S in plan view. The turning slider member 166 is supported by the turning link 165 so as to be rotatable around the transmission axis S. The turning slider member 166 is engaged with the circular cam 134 so as to be slidable in the circumferential direction, similarly to the shifting slider member 157.

  As shown in FIG. 19, the turning slider member 166 rotates on the shaft 166a attached to the turning link 165, a sphere 166b (spherical portion) integrally provided at the tip of the shaft 166a, and the sphere 166b. The ring body 166c is fitted so as to be freely tiltable in any direction with respect to the axis of the shaft portion 166a. The ring body 166c is inserted into the cam groove 134a of the circular cam 134 so as to be slidable and rotatable.

  As shown in FIG. 11, the axis AX1 of the intermediate shaft 155 and the axis AX2 of the turning output shaft 164 are located on substantially the same plane. Further, as shown in FIG. 15, the turning radius r1 of the straight link 156 (the length from the intermediate shaft 155 to the shifting slider member 157) and the turning radius r2 of the turning link 165 (turning from the turning output shaft 164). The length to the slider member 166 for use) is set to substantially the same length (r1≈r2).

  On the other hand, the turning output arm 167 fixed to the outer end of the turning output shaft 164 is linked to a turning control shaft 189 protruding upward from the turning HST mechanism 54 via a turning relay rod 180. The turning control shaft 189 is configured to rotate via the turning relay rod 180 when the turning output shaft 164 rotates. In the embodiment, one end of the turning relay rod 180 is pivotally attached to the turning output arm 167 of the turning output shaft 164 via a laterally attached pivot pin. The other end of the turning relay rod 180 is pivotally attached to a turning operation arm 188 fixed to the turning control shaft 189 via a longitudinally attached pivoting pin. In the embodiment, the turning relay rod 180 extends above the straight traveling relay rod 140 (see FIGS. 5 to 8).

  The turning control shaft 189 is for adjusting the inclination angle (swash plate angle) of the rotary swash plate of the second hydraulic pump 57 in the turning HST mechanism 54, and is an adjustment for adjusting the shift output of the turning HST mechanism 54. It functions as a part. That is, by adjusting the swash plate angle of the second hydraulic pump 57 by forward / reverse rotation of the turning control shaft 189, the rotational speed control and forward / reverse switching of the second hydraulic motor 58 are executed, and the traveling machine body 1 is steered. Stepless change of the angle (turning radius) and switching of the left and right turning directions are performed.

(4). Next, the operation of the mechanical interlocking mechanism 121 when the main transmission lever 13 and the steering handle 10 are operated will be described with reference to FIGS.

  When the main transmission lever 13 is in the neutral position, the slider 125 on the turning input shaft 122 does not slide back and forth, so that the control body 131 is held in the horizontal position at the neutral position and does not tilt and rotate around the transmission axis S. . In this state, even if the steering handle 10 is rotated in either the left or right direction, both the shifting slider member 157 and the turning slider member 166 engaged with the circular cam 134 of the control body 131 rotate. Does not move in the direction of the axis P. The relay shaft 155 (transmission output shaft 136) and the turning output shaft 164 are maintained in a stopped state. Therefore, both HST mechanisms 53 and 54 (first hydraulic motor 56 and second hydraulic motor 58) do not operate.

  That is, in a state where the main transmission lever 13 is in the neutral position and the traveling machine body 1 is stopped, even if the steering handle 10 is rotated by an operator's inadvertent contact or the like, both the HST mechanisms 53 and 54 are Without driving, the traveling machine body 1 can be reliably maintained in the stopped state. Therefore, for example, when performing maintenance work, it is possible to reliably avoid the possibility that the traveling machine body 1 behaves unexpectedly against the operator's intention by simply setting the main speed change lever 13 to the neutral position, thereby ensuring sufficient safety. Can be secured.

  Next, when the main transmission lever 13 is tilted from the neutral position while the steering handle 10 is maintained at the neutral position (straight running position), the slider 125 moves in the direction of the turning axis P in conjunction with this. , And the control body 131 rotates in the forward and reverse tilt directions around the transmission axis S (see the two-dot chain line state in FIG. 16). That is, the shifting slider member 157 engaged with the portion on the orthogonal axis W of the circular cam 134 moves up and down from the neutral position by a distance L1 or L2 along the turning axis P of the turning input shaft 122.

  Note that the sliding slider member 166 engaged with the portion on the transmission axis S of the circular cam 134 does not move in the direction of the turning axis P due to the sliding movement of the slider 125. Further, before the main transmission lever 13 is tilted from the neutral position, the switching operation mechanism 169 is operated to engage the pin 163 of the switching member 162 with the transmission output link 158 so that the transmission output link 158 and the transmission output shaft 136 are engaged. The transmission output link 158 and the transmission output shaft 136 are coupled such that the transmission output link 136 and the transmission output link 136 rotate together.

  As described above, when the shifting slider member 157 is moved by the sliding movement of the slider 125, the movement of the shifting slider member 157 in the direction of the turning axis P is changed by the straight link 156, the connecting link 159, and the shift output. The signal is transmitted to the straight travel control shaft 149 (the straight travel HST mechanism 53) via the link 158, the switching member 162, the speed change output shaft 136, the speed change output arm 139, and the straight travel relay rod 140. That is, when the shifting slider member 157 is moved in the direction of the turning axis P, the swash plate (the straight-traveling HST mechanism 53) of the first hydraulic pump 55 is caused by the rotation of the circular cam 134 around the shifting axis S. Shifting from the neutral position.

  On the other hand, since the turning slider member 166 is engaged with the portion of the circular cam 134 on the transmission axis S in the control body 131, the circular cam 134 (the control body 131) rotates forward and backward around the transmission axis S. However, unless the steering handle 10 is operated, the turning slider member 166 does not move in the direction of the turning axis P, and the swash plate (the turning HST mechanism 54) of the second hydraulic pump 57 is shifted from the neutral position. There is nothing. Accordingly, the same rotational speed (same rotational direction) is simultaneously transmitted from the straight traveling HST mechanism 53 to both the left and right traveling crawlers 2, and the traveling machine body 1 travels straight forward or backward.

  The travel speed (vehicle speed) during straight travel is determined by the amount of rotation of the straight travel control shaft 149 in the straight travel HST mechanism 53. The amount of rotation is determined by movement distances L1 and L2 in the direction of the turning axis P of the shifting slider member 157 (inclination rotation angles α1 and α2 of the circular cam 134 from the neutral position). The tilt rotation angles α1 and α2 of the circular cam 134 are increased or decreased by the tilting operation amount of the main transmission lever 13, so that the traveling machine body 1 is traveling straight ahead in proportion to the operation amount from the neutral position of the main transmission lever 13. The traveling speed of the vehicle can be adjusted.

  Next, when the steering handle 10 is rotated left or right from the neutral position while the main speed change lever 13 is operated to a position other than the neutral position, and the turning input shaft 122 is rotated, the circular cam 134 is rotated. The (control body 131) rotates together with the turning input shaft 122 while being tilted and rotated about the transmission axis S. Then, the turning slider member 166 that engages with the portion of the circular cam 134 on the transmission axis S moves in the direction of the turning axis P by the rotation of the turning input shaft 122. The movement of the turning slider member 166 in the direction of the turning axis P moves through the turning link 165, the turning output shaft 164, the turning output arm 167, and the turning relay rod 180 through the second hydraulic pump 57 (the turning HST mechanism 54). ) Of the turning control shaft 189. As a result, the swash plate angle of the second hydraulic pump 57 is changed to a position other than the neutral position, and the second hydraulic pump 57 (the turning HST mechanism 54) is shifted.

  For this reason, rotations in the opposite directions (the same number of rotations) are simultaneously transmitted from the second hydraulic motor 58 to the left and right traveling crawlers 2 by the shift operation from the neutral position of the second hydraulic motor 58 (the turning HST mechanism 54). Is done. That is, since a speed difference is given between the left and right traveling crawlers 2, the traveling machine body 1 turns in the direction in which the steering handle 10 is operated. That is, the course of the traveling machine body 1 is changed by operating the steering handle 10.

  The shift operation amount from the neutral position of the second hydraulic pump 57 (the turning HST mechanism 54), that is, the turning amount of the turning control shaft 149 is the turning operation angle (turning operation amount) from the neutral position of the steering handle 10. ). That is, the amount of movement of the turning slider member 166 in the direction of the turning axis P when the control body 131 is rotated by the turning input shaft 122 in a state where the control body 131 is rotated forward and backward around the transmission axis S is The shift operation amount of the mechanism 54 is proportional. Therefore, the speed difference between the left and right traveling crawlers 2 due to the shifting operation of the turning HST mechanism 54 increases in proportion to the rotation operation angle (rotation operation amount) from the neutral position of the steering handle 10, and the traveling machine body 1. The turning radius becomes smaller.

  In particular, in the embodiment, the shift slider member 157 engaged with the circular cam 134 is moved in the direction of the swing axis P by the tilt rotation of the circular cam 134 around the transmission axis S. In this case, the straight traveling control shaft 149 is rotated in the opposite direction, and the straight traveling speed (the turning speed of the traveling machine body 1) of the left and right traveling crawlers 2 can be reduced corresponding to the turning radius at that time.

  That is, when the steering handle 10 is turned from the neutral position, the circular cam 134 (the control body 131) is turned by the turning input shaft 122 in a state in which the circular cam 134 is rotated around the transmission axis S. Then, as the circular cam 134 rotates, the shifting slider member 157 that engages with the circular cam 134 moves so as to approach the portion on the transmission axis S from the portion on the orthogonal axis W of the circular cam 134. . For this reason, the movement distances L1 and L2 in the direction of the turning axis P of the speed change slider member 157 are smaller than those in the case where the moving distance L1 and L2 are positioned on the orthogonal axis W of the circular cam 134. That is, the rotation amount of the rectilinear control shaft 149 (the shift operation amount of the rectilinear HST mechanism 53) is reduced. As a result, the straight rotation speed transmitted from the first hydraulic motor 56 to the left and right traveling crawlers 2 is controlled in the deceleration direction, and the traveling speed when the traveling machine body 1 turns is slowed. In this case, the speed at the center between the left and right traveling crawlers 2 becomes slow, and the moving speed of the traveling crawler 2 outside the turn is maintained at a speed approximating the straight traveling speed before deceleration.

  Accordingly, as the amount of rotation of the steering handle 10 increases, the speed difference between the left and right traveling crawlers 2 increases, the turning radius decreases, and the moving speed in the straight traveling direction decreases. Since the traveling speed (vehicle speed) becomes slow, it is possible to reduce the centrifugal force acting on the traveling machine body 1 (operator) outwardly during turning. The side slip of the left and right traveling crawlers 2 can be reduced. In addition, when the steering wheel 10 is moved forward and backward, the tilt rotation direction of the control body 131 (circular cam 134) around the transmission axis S is reversed with respect to the rotation operation of the steering handle 10. In any case, the turning operation direction of the steering handle 10 and the turning direction of the traveling machine body 1 coincide.

  By the way, automatically decelerating the moving speed of the traveling machine body 1 in proportion to the rotation operation angle (rotation operation amount) of the steering handle 10 is a two-travel crawler when the ground is soft like a wet field. There is a risk of increasing the amount of sinking (sinking amount) into the ground. That is, by reducing the turning radius of the traveling machine body 1, the rotational speed of the traveling crawler 2 inside the turning is significantly reduced as compared with the rotational speed of the traveling crawler 2 outside the turning. As such, when the rotational speed of the traveling crawler 2 is significantly reduced, the traveling crawler 2 may sink significantly in a wet field where the ground is soft.

  In such a case, the operation of the switching member 162 by the switching operation mechanism 169 switches the state in which the speed change output link 98 is coupled to the speed change output shaft 136 to the state in which the non-deceleration arm 160 is coupled to the speed change output shaft 136. . When the non-deceleration arm 160 is coupled to the speed change output shaft 136, the moving speed (straight forward moving speed) of the traveling machine body 1 is equal to the set speed of the main speed change lever 13 regardless of the turning angle (steering angle) of the steering handle 10. Maintained. As described above, the traveling speed of the traveling machine body 1 is reduced in proportion to the turning angle (steering angle) of the steering handle 10 as compared with the direction in which the turning radius of the traveling machine body 1 is reduced as compared with the deceleration speed. Even if the steering handle 10 is operated, the amount of deceleration of the traveling crawler 2 inside the turn is small.

  When the non-decelerating arm 160 is coupled to the speed change output shaft 136, the operation of the main speed change lever 13 is performed as it is regardless of the turning operation of the steering handle 10, and the interlocking connecting means 138, the main speed change arm 137, the main speed change lever input shaft. 135, the main transmission fork arm 151, the non-deceleration arm 160, the transmission output shaft 136, the transmission output arm 139, and the straight traveling relay rod 140 are transmitted to the straight traveling control shaft 149 of the straight traveling HST mechanism 53. For this reason, the turning operation of the steering handle 10 and the tilting operation of the main transmission lever 13 are not directly related. The traveling speed of the traveling machine body 1 is released from the state where the traveling speed of the traveling machine body 1 is decelerated through the circular cam 134 in conjunction with the steering of the steering handle 10. A traveling speed (vehicle speed) proportional to the tilting operation amount of the main transmission lever 13 is maintained. Therefore, even if the course of the traveling machine body 1 is changed, the amount of deceleration of the traveling crawler 2 inside the turn becomes small, and the rotational speed of the traveling crawler 2 inside the turning can be maintained at a predetermined value or more. As a result, it is possible to make the combine into a wetland specification so as to suppress sinking into the soft ground (sinking of the traveling crawler 2).

  According to the above configuration, the control body 131 that can be rotated around the rotation axis P and the transmission axis S that are orthogonal to each other is provided. The control body 131 is forward / reverse about the rotation axis P accompanying the operation of the steering handle 10. The turning HST mechanism 54 is actuated by rotation, and the rectilinear HST mechanism 53 is actuated by forward / reverse rotation around the transmission axis S associated with the operation of the main transmission lever 13. Therefore, “when the steering handle 10 is rotated to a position other than neutral in a state where the main transmission lever 13 is tilted to a position other than neutral, the traveling vehicle body 1 is rotated with a smaller turning radius as the amount of rotation operation increases. The operation of “turn left or right” can be executed by both the forward / reverse rotation around the turning axis P and the forward / reverse rotation around the transmission axis S in the control body 131. That is, the control body 131 operates the turning steering function for operating the turning HST mechanism 54 in conjunction with the turning operation of the steering handle 10 and the straight-traveling HST mechanism 53 in conjunction with the tilting operation of the main transmission lever 13. It has both functions of running gear shifting function.

  Therefore, the number of components of the mechanical interlocking mechanism 121 can be reduced as compared with the structure of the operation system using many long rods, arms, pivot pins and the like as in Patent Document 1. It is possible to avoid variations in the operation of the mechanical interlocking mechanism 121 due to precise processing accuracy and assembly accuracy. Adjustment work and the like when assembling the mechanical interlocking mechanism 121 can be simplified as compared with the conventional art. That is, workability such as assembly or maintenance of the mechanical interlocking mechanism 121 can be improved while the mechanical interlocking mechanism 121 can be configured at low cost.

  Further, in the embodiment, the axis AX2 of the turning output shaft 164 that rotates in conjunction with the turning operation of the steering handle 10 and the axis AX1 of the intermediate shaft 155 that rotates in conjunction with the tilting operation of the main transmission lever 13 are provided. Are positioned substantially on the same plane, the operating range of the control body 131 (particularly, the vertical tilt rotation range around the transmission axis S) is limited. Compared to the structure of an operation system that uses many long rods, arms, pivot pins, and the like as in Patent Document 1, the size of the mechanical interlocking mechanism 121 along the turning axis P can be significantly shortened.

  Therefore, the structure of the mechanical interlocking mechanism 121 can be remarkably simplified and reduced in size compared with the case of Patent Document 1, and the entire operation system can be made compact. As a result, it is possible to contribute to space saving around the control unit 9 of the traveling machine 1.

  In particular, in the embodiment, the turning radius r1 of the rectilinear link 156 and the turning radius r2 of the turning link 165 are set to substantially the same length (r1≈r2). It can be made more compact. In addition, in the embodiment, since the mechanical interlocking mechanism 121 (control body 131) is built in the mission case 18, the steering column that supports the steering handle 10 can be reduced in size or eliminated. A wide space around the portion 9 can be secured.

  Further, the lateral turning input shaft 122 is built in the mission case 18, and the control body 131 can turn and rotate around the speed change axis S orthogonal to the turning axis P of the turning input shaft 122. On the other hand, the swing input shaft 122 is provided with a slider 125 that rotates together with the swing input shaft 122 so as to be able to reciprocate along the swing axis P. The main speed change lever 13 and the slider 125 are connected to each other. The slider 125 is connected so as to reciprocate along the turning axis P by the operation of the lever 13. The slider 125 and the control body 131 are linked to the reciprocating movement of the slider 125 so that the control body 131 is connected to the speed change axis. It is connected so as to tilt and rotate around S. For this reason, the influence of gravity can be reduced with respect to the reciprocating motion of the slider 125 on the lateral turning input shaft 122. Similarly, the influence of gravity on the tilt rotation of the control body 131 can be reduced. Therefore, the operability of the slider 125 and the control body 131 and, in turn, the operability of the main transmission lever 13 can be improved.

  By the way, when traveling on the farm field, the left and right traveling crawler 2 generates a propulsive force while scratching the mud in the farm field, and mud and swarf swells are easily formed at the front part thereof. In this regard, in the embodiment, the box portion 120 that accommodates the control body, the turning input shaft, and the slider in the mission case 18 is disposed at a height position higher than the upper surface of the left and right traveling crawler 2, so the box portion 120 is raised. There is little risk of bumping into mud or covering with mud or sawdust. Therefore, it can suppress that mud and swarf penetrate | invade in a box part, and can reduce a possibility that mud and swarf will enter into the box part 120, and damage the mechanical interlocking mechanism 121. FIG.

  As shown in FIG. 18, a speed change slider member 157 in which a sphere 157c slidably fitted in a cam groove 134a of a circular cam 134 is rotatably supported on a straight link 156 by a shaft portion 157a. This configuration can greatly reduce the sliding frictional resistance between the circular cam 134 and the sphere 157c.

  Further, as shown in FIG. 19, a ring body 166c that is slidably fitted in a cam groove 134a of a circular cam 134 is rotatable to a spherical body 166b that is integral with a shaft portion 166a attached to a turning link 165, and the shaft The configuration of the turning slider member 166 that is fitted so as to be freely tiltable in an arbitrary direction with respect to the axis of the portion 166a is the same as described above, and the sliding friction resistance between the circular cam 134 and the sphere 166b. Can be greatly reduced. The sphere 166b is a perfect sphere.

  Needless to say, the shifting slider member 157 may have the configuration shown in FIG. 19 instead of the configuration shown in FIG. The turning slider member 166 may have the configuration shown in FIG. 18 instead of the configuration shown in FIG.

  The present invention is not limited to the above-described embodiment, and can be embodied in various forms. For example, the present invention is not limited to the above-described combine, but can be widely applied to various traveling vehicles such as farm work machines such as tractors and rice transplanters, and special work vehicles such as crane cars. Moreover, the structure of each part in this invention is not limited to embodiment of illustration, A various change is possible in the range which does not deviate from the meaning of this invention.

DESCRIPTION OF SYMBOLS 1 Traveling machine body 9 Steering part 10 Steering handle 13 Main shift lever 18 Transmission case 53 Straight-travel HST mechanism (straight-shift transmission)
54 HST mechanism for turning (turning transmission)
120 Box part 121 Mechanical interlocking mechanism 122 Rotation input shaft 125 Slider 131 Control body 136 Variable speed output shaft 140 Relay rod for straight travel 149 Linear motion control shaft 155 Intermediate shaft (transverse shaft for straight travel)
156 Linear link 157 Shifting slider member 158 Shifting output link 164 Turning output shaft (turning conversion shaft)
165 Rotating link 166 Rotating slider member 180 Rotating relay rod 189 Rotating control axis P Rotating axis S Shifting axis W Orthogonal axis

Claims (2)

A straight and turning transmission that shifts the power of an engine mounted on the traveling machine body, a straight operation tool that controls the straight output of the straight transmission, and a turning operation that controls the turning output of the turning transmission A traveling vehicle equipped with tools,
It has a control body that can rotate around a rotation axis and a transmission axis that are orthogonal to each other,
The turning body is operated by forward / reverse rotation around the turning axis of the control body in accordance with the operation of the turning operation tool, while the turning body of the control body around the speed change axis in accordance with the operation of the linear operation tool. Is configured to actuate the linear transmission by forward and reverse rotation of
The control body is built in a transmission case that transmits output from each transmission to the left and right traveling units ,
A lateral turning input shaft that is rotated by operation of the turning operation tool is built in the mission case, and the control body is tilted and rotated about the speed change axis that is orthogonal to the turning axis of the turning input shaft. While being provided on the swivel input shaft,
The turning input shaft is provided with a slider that rotates together with the turning input shaft so as to be able to reciprocate along the turning axis. The linear operation tool and the slider can be operated by operating the linear operation tool. Connected to reciprocate along the pivot axis,
The slider and the control body are connected so that the control body tilts and rotates around the speed change axis in conjunction with the reciprocation of the slider.
Traveling vehicle. Of the transmission case, a box portion that houses the control body, the turning input shaft, and the slider is disposed at a height position higher than the upper surfaces of the left and right traveling portions.
The traveling vehicle according to claim 1.

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