JP2007091158A - Traveling transmission device for working vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a traveling transmission device capable of performing steering operation by a simple structure. <P>SOLUTION: A main steering clutch body 33 is integrally rotatably and slidably supported to a main drive shaft 29 and a sub-steering clutch body 71 is integrally rotatably and slidably supported to a sub-drive shaft 12 transmitted through a turning clutch 60, respectively. The main steering clutch body 33 is slide-operated by the steering operation body 82 and engaged and disengaged with and from a main left traveling transmission gear 31a interlocked with a drive shaft 1a of a left side traveling device through a high speed gear transmission mechanism 40 and a main right traveling transmission gear 31b interlocked with a drive shaft 1b of a right side traveling device through a high speed gear transmission mechanism 50. The sub-steering clutch body 71 is slide-operated by being interlocked with the main steering clutch body 33 by the steering operation body 82 and engaged and disengaged with and from a sub-left traveling transmission gear 73 interlocked with the drive shaft 1a of the left side traveling device through a low speed gear transmission mechanism 90 and a sub-right traveling transmission gear 74 interlocked with the drive shaft 1b of the right side traveling device through a low speed gear interlocking mechanism 100. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a traveling transmission device for a work vehicle.

As a traveling power transmission device for a combine as an example of a work vehicle, a conventional one shown in Patent Document 1, for example, has been developed.
Patent Document 1 discloses that a shift output of a hydrostatic continuously variable transmission 8 is transmitted to a center gear G11 that is transmitted via a second passive gear G9 of an auxiliary transmission mechanism 11, and an axle 22L of a left traveling device 1L. A side clutch 20L is provided between the connected axle gear 21L, a side clutch 20R is provided between the center gear G11 and the axle gear 21R connected to the axle 22R of the right traveling device 1R, and the center gear G11. The gear C12 connected to the clutch C, the fifth shaft 26, the steering side gear 25L linked via the gear 27L, and the gear C12 connected to the center gear G11 to the clutch C, the fifth shaft 26, a steering side gear 25R that is linked via a gear 27R, and the side clutch gear 23L of the side clutch 20L is engaged with the center gear G11. When the shift operation is further performed beyond the clutch disengaged position, the side clutch gear 23R of the side clutch 20R is engaged with the steering side gear 25L, and the side clutch gear 23R of the side clutch 20R is disengaged from the center gear G11. By being further shifted beyond this, it is engaged with the steering side gear 25R.

That is, when the side clutches 20L and 20R are operated to the engagement position where they are engaged with the center gear G11, both the left traveling device 1L and the right traveling device 1R are in a normal driving state, and the airframe travels straight.
The side clutches 20L, 20R corresponding to the traveling devices 1L, 1R on the outer side of the turn are operated to the engagement positions engaged with the center gear G11, and the side clutches 20R, 20L corresponding to the traveling devices 1R, 1L on the inner side of the turning are operated to the center gear G11. When the vehicle is moved to a position that is not engaged with the steering side gears 25L and 25R, the traveling devices 1L and 1R on the outside of the turn are in a normal driving state, and the traveling devices 1R and 1L on the inside of the turn are in a neutral state Then the aircraft turns.
The side clutches 20L, 20R corresponding to the traveling devices 1L, 1R on the outer side of the turn are operated to the engagement positions engaged with the center gear G11, and the side clutches 20R, 20L corresponding to the traveling devices 1R, 1L on the inner side of the turning are used for steering. When the gears are engaged with the side gears 25L and 25R and the clutch C is engaged, the traveling devices 1L and 1R on the outside of the turn are in a normal driving state, and the traveling devices 1R and 1R on the inside of the turn The 1L is driven at a lower speed than the traveling devices 1L and 1R outside the turn, and the aircraft turns with a relatively large turning radius.

JP 2001-193835 (paragraphs [0032], [0033], [0052] [0053], FIG. 2)

  In the above-described conventional travel transmission device, transmission of the left and right travel devices is switched on and off and the speed is switched by an actuator so that the aircraft can be steered only by lightly operating the steering operation tool. It is necessary to provide a pair of actuators such as a pair of hydraulic pistons for switching the side clutch 20L and the side clutch 20R separately, which tends to increase the cost in terms of the required number of actuators.

  An object of the present invention is to provide a traveling transmission device for a work vehicle that can be completed with a small number of actuators even when an actuator is employed so that the steering operation can be performed lightly as described above.

In the traveling transmission device for a work vehicle according to the first invention,
A main drive shaft and a sub drive shaft transmitted via a swing clutch are provided so as to be relatively rotatable,
A main left traveling transmission gear linked to the left traveling device via a high speed gear transmission mechanism, a main right traveling transmission gear linked to the right traveling device via a high speed gear transmission mechanism, and integral rotation and sliding on the main drive shaft A main steering clutch body that is freely supported and detachable from the main left traveling transmission gear and the main right traveling transmission gear;
A sub-left travel transmission gear linked to the left travel device via a low-speed gear transmission mechanism; a sub-right travel transmission gear linked to the right travel device via a low-speed gear transmission mechanism; A sub-steering clutch body that is slidably supported and detachably engageable with the sub-left travel transmission gear and the sub-right travel transmission gear;
When the main steering clutch body is in a rectilinear position engaged with the main left travel transmission gear and the main right travel transmission gear, the sub steering clutch body is connected to the sub left travel transmission gear and the sub right travel transmission gear. When the main steering clutch body engages with the main left traveling transmission gear and enters the right turning position in which the main steering clutch body is disengaged from the main right traveling transmission gear, the sub steering clutch body is moved to the sub steering clutch body. The left steering gear is disengaged and engaged with the sub-right travel transmission gear, and the main steering clutch body is disengaged from the main left travel transmission gear and is engaged with the main right travel transmission gear. When in the turning position, the main steering clutch body and the sub steering clutch body so that the sub steering clutch body engages with the sub left traveling transmission gear and is disengaged from the sub right traveling transmission gear. And the ream It is provided with a steering operating tool sliding operation by.

  That is, if the steering operation body is operated, the steering operation body switches the main steering clutch body to the straight movement position, the left turning position, and the right turning position, and the steering operation body moves to the sub steering clutch. The body is slid in conjunction with the main steering clutch body. When the main steering clutch body is operated to the rectilinear position, the main steering clutch body engages with the main left traveling transmission gear and the main right traveling transmission gear, and the main drive shaft is the main steering clutch body and the main left traveling transmission gear. The left traveling device is linked to the left traveling device via the gear and the high speed gear transmission mechanism, and the right traveling device is coupled to the main steering clutch body, the main right traveling transmission gear, and the high speed gear transmission mechanism. At this time, the auxiliary steering clutch body is engaged with the auxiliary left traveling transmission gear and the auxiliary right traveling transmission gear, the auxiliary drive shaft is connected to the left traveling device via the auxiliary steering clutch body and the low speed gear transmission mechanism, and The steering gear body and the low-speed gear transmission mechanism are linked to the right traveling device, respectively, but when the turning clutch is operated in the disengaged state, the auxiliary drive shaft is in the idle state. As a result, the left and right traveling devices are driven by the driving force transmitted from the main drive shaft via the high-speed gear transmission mechanism, so that the airframe travels straight.

  When the main steering clutch body is operated to the left turning position, the main steering clutch body engages with the main right traveling transmission gear and is disengaged from the main left traveling transmission gear. It is linked to the right traveling device via the right traveling transmission gear and the high-speed gear transmission mechanism. At this time, the auxiliary steering clutch body engages with the auxiliary left traveling transmission gear and is disengaged from the auxiliary right traveling transmission gear, and the auxiliary drive shaft is interlocked with the left traveling device via the auxiliary steering clutch body and the low speed gear transmission mechanism. . At this time, when the turning clutch is operated in the disengaged state, the auxiliary drive shaft is in the idle state, the left traveling device is stopped, and the right traveling device is transmitted from the main drive shaft via the high speed gear transmission mechanism. Since the vehicle is driven by the driving force, the aircraft turns left. On the other hand, when the turning clutch is operated in the engaged state, the sub drive shaft is driven, and the left traveling device is driven by the driving force transmitted from the sub drive shaft through the low speed transmission gear mechanism by the right traveling device. Is also driven at a low speed, and the aircraft turns left with a turning radius due to the speed difference between the left and right traveling devices.

  When the main steering clutch body is operated to the right turning position, the main steering clutch body engages with the main left traveling transmission gear and is disengaged from the main right traveling transmission gear, and the main drive shaft is the main steering clutch body, It is linked to the left travel device via the main left travel transmission gear and high-speed gear transmission mechanism. At this time, the sub steering clutch body engages with the sub right traveling transmission gear and is disengaged from the sub left traveling transmission gear, and the sub drive shaft is interlocked with the right traveling apparatus via the sub steering clutch body and the low speed gear transmission mechanism. . At this time, when the turning clutch is operated in the disengaged state, the sub drive shaft is idled, the right traveling device is stopped, and the left traveling device is transmitted from the main drive shaft via the high speed gear transmission mechanism. Because the vehicle is driven by the driving force, the aircraft turns right. On the other hand, when the turning clutch is operated to be in the engaged state, the sub drive shaft is driven, and the right travel device is driven by the driving force transmitted from the sub drive shaft through the low speed transmission gear mechanism from the left travel device. Is also driven at a low speed, and the aircraft turns right with a turning radius due to the speed difference between the left and right traveling devices.

  Therefore, according to the first aspect of the present invention, while the traveling device corresponding to the outside of the turn is driven by the power transmitted by the high-speed transmission gear mechanism, the traveling device corresponding to the inside of the turning is stopped, and the aircraft turns slightly or turns outward. While the corresponding traveling device is driven by the power transmitted by the high-speed transmission gear mechanism, the traveling device corresponding to the inside of the turn is driven at a lower speed than the traveling device outside the turn by the power transmitted by the low-speed transmission gear mechanism, and the aircraft turns around. Even when adopting an actuator so that the steering operation can be performed lightly, it is only necessary to equip the actuator to be interlocked with the steering operation body. It can be obtained inexpensively.

  According to the second aspect of the invention, in the configuration of the first aspect of the invention, the main steering clutch body is in the main left traveling transmission gear and the main right traveling in a state in which the main steering clutch body is in the straight traveling position. The length of engagement in the sliding direction of the main steering clutch body engaged with the transmission gear is set so that the sub steering clutch body is in the sub left traveling transmission gear in a state in which the main steering clutch body is in the rectilinear position. The engagement length in the sliding direction of the auxiliary steering clutch body that engages with the auxiliary right travel transmission gear is longer.

  When the main steering clutch body is switched from the left turn position or the right turn position to the straight drive position, the main steering clutch body is the main left traveling transmission gear or main right The sub-steering clutch body is engaged with the traveling transmission gear, and the sub-steering clutch body is slid in conjunction with the main steering clutch body. Engaged with the transmission gear. At this time, when the engagement length of the main steering clutch body is longer than the engagement length of the auxiliary steering clutch body, the main steering clutch body precedes the auxiliary steering clutch body and the gear to be engaged. After that, both the steering clutch bodies can be engaged with each other so that the auxiliary steering clutch body is engaged with the engagement target gear. As a result, the main steering clutch body is also sub-steered compared to the case where the main steering clutch body and the sub-steering clutch body are engaged with the gears to be engaged at the same time, and both the steering clutch bodies are engaged. The two steering clutch bodies can be engaged with each other while the clutch body is easily aligned with the engagement target gear so as to be engaged.

  Therefore, according to the second aspect of the present invention, the main steering clutch body and the auxiliary steering clutch body can be slid in conjunction with each other by the steering operation body. It is possible to easily perform the steering operation quietly and smoothly by easily aligning with the gear to be meshed and causing the gear to squeeze without being generated and switching quickly.

  According to the third aspect of the present invention, in the configuration of the first or second aspect of the present invention, the auxiliary steering clutch body is rotated in the direction of rotation of the auxiliary steering clutch body, the auxiliary left traveling transmission gear, and the auxiliary right traveling transmission gear. Is greater than the meshing interchange of the main steering clutch body with the main left traveling transmission gear and the main right traveling transmission gear in the rotational direction of the main steering clutch body.

  The main left travel transmission gear and the main right travel transmission gear are linked to the travel device via the high speed gear transmission mechanism, and the sub left travel transmission gear and the sub right travel transmission gear are linked to the travel device via the low speed gear transmission mechanism. Therefore, when the main steering clutch body is operated to the turning position and the main left traveling transmission gear or the main right traveling transmission gear is driven, the sub left traveling transmission gear or the sub right traveling is released. The transmission gear is transmitted through a low-speed gear transmission mechanism, and the sub left traveling transmission gear or the sub right traveling transmission gear is driven at a higher speed than the main left traveling transmission gear and the main right traveling transmission gear. That is, when the main steering clutch body is switched from the turning position to the straight traveling position, the sub steering clutch body is driven at a higher speed than the main steering clutch body, or the sub left traveling transmission gear. Engage with the gear. According to the third aspect of the present invention, the engagement between the auxiliary steering clutch body, the auxiliary left traveling transmission gear, and the auxiliary right traveling transmission gear is obtained by combining the main steering clutch body, the main left traveling transmission gear, and the main right traveling transmission gear. Since it is larger than the meshing accommodation, the sub steering clutch body is engaged with the sub left traveling transmission gear and the sub right traveling transmission gear regardless of the high speed rotation of the sub left traveling transmission gear and the sub right traveling transmission gear. The sub steering clutch body can be engaged with the sub left traveling transmission gear or the sub right traveling transmission gear while facilitating alignment in a matched state.

  Therefore, according to the third aspect of the invention, the main steering clutch body that transmits at high speed to the traveling device and the sub-steering clutch body that transmits at low speed to the traveling device are operated to slide by being interlocked by the steering operation body. The sub steering clutch body can be easily aligned with the sub left traveling transmission gear and the sub right traveling transmission gear so that the gears can be switched quickly and the steering operation can be performed quietly and smoothly. Can do.

  In the fourth aspect of the present invention, in the configuration of the third aspect of the present invention, the rotation direction of the auxiliary steering clutch body in which the auxiliary steering clutch body engages with the auxiliary left travel transmission gear in a freely transmitting manner, The sub-steering clutch body is engaged with the sub-right traveling power transmission gear so that the sub-steering clutch body is engaged with the sub-steering clutch body in a freely rotating manner.

  When the meshing interchange between the main steering clutch body and the main left traveling transmission gear and the main right traveling transmission gear is provided, the main steering clutch body is switched from the turning position to the straight traveling position, and the main left traveling transmission gear When engaging with the right travel transmission gear, the main steering clutch body engagement protrusion is on the upper side in the main steering clutch body rotation direction with respect to the main left travel transmission gear and main right travel transmission gear engagement protrusion. The state where the engagement protrusion of the main steering clutch body is in contact with the engagement protrusion of the main left traveling transmission gear or the main right traveling transmission gear on the lower transmission surface of the engaging steering protrusion in the main steering clutch body rotation direction. (Hereinafter referred to as the front engagement state) and the engagement protrusion of the main steering clutch body is the main steering with respect to the engagement protrusion of the main left traveling transmission gear and the main right traveling transmission gear. Located on the lower side in the direction of clutch body rotation, the engagement protrusion of the main steering clutch body Engage in a state (hereinafter referred to as a back engagement state) in which the transmission surface on the upper side of the starting main steering clutch body is in contact with the engagement protrusions of the main left traveling transmission gear and the main right traveling transmission gear. There are cases.

  The rotation direction of the sub steering clutch body in which the sub steering clutch body engages freely with the sub left traveling transmission gear, and the sub steering clutch body engages freely with the sub right traveling transmission gear. When the rotational phase of the sub-steering clutch body is the same, the main steering clutch body that is operated to switch from the turning position to the straight-ahead position is engaged with the main left traveling transmission gear or the main right traveling transmission gear in the above-mentioned reverse engagement state. When the main steering clutch body is engaged with the main left traveling transmission gear or the main right traveling transmission gear, the auxiliary steering clutch body becomes the sub right traveling transmission gear or the sub left traveling transmission gear. The sub-left traveling transmission gear or the sub-right traveling transmission gear that has been rotated due to the driving force transmitted from the main steering clutch body through the high-speed transmission gear mechanism and the low-speed transmission gear mechanism during the turning traveling because of meshing The driving force of the secondary steering clutch body, secondary right traveling transmission gear or Sub left traveling transmission gear, low speed transmission gear mechanism, via a high-speed transmission gear mechanism transmitted to the main left traveling power transmission gear or main right traveling power transmission gear on the way that meshing operation of the main steering clutch body is performed. Then, the main steering clutch body engaged with the main left traveling transmission gear and the main right traveling transmission gear generates a large amount of friction due to the rotation of the main left traveling transmission gear and the main right traveling transmission gear. It becomes difficult to slide with respect to the left traveling transmission gear or the main right traveling transmission gear.

  In contrast, in the fourth aspect of the present invention, the rotation direction of the sub steering clutch body in which the sub steering clutch body engages with the sub left traveling transmission gear in a freely transmitting manner, and the sub steering clutch body is the sub steering clutch body. The main steering clutch body that is switched from the turning position to the straight movement position is the main left traveling transmission because the rotation phase of the sub-steering clutch body that engages with the right traveling transmission gear is freely changed. Even when engaged with the gear or the main right travel transmission gear in the reverse engagement state, the sub left travel transmission gear or the sub right drive is located between the sub steering clutch body and the sub left travel transmission gear or the sub right travel transmission gear. Drive that is transmitted through the high-speed transmission gear mechanism and the low-speed transmission gear mechanism from the main steering clutch body during turning while the traveling transmission gear rotates relative to the sub-steering clutch body. Sub left driving gear that was rotating for power or While the driving force of the right traveling transmission gear is not transmitted to the main left traveling transmission gear or the main right traveling transmission gear, the main steering clutch body can easily slide on the main left traveling transmission gear or the main right traveling transmission gear, The main steering clutch body can be engaged with the main left traveling transmission gear or the main right traveling transmission gear so that the engagement length in the sliding direction of the main steering clutch body becomes a predetermined length.

  Therefore, according to the fourth aspect of the present invention, the main steering clutch body that is switched from the turning position to the straight traveling position is provided in the main steering clutch body and the sub-steering clutch body. The left traveling transmission gear and the main right traveling transmission gear can be quickly and lightly engaged so that the steering operation can be performed smoothly.

Embodiments of the present invention will be described below with reference to the drawings.
As shown in FIG. 1, a front end of a body frame 4 of a self-propelled machine body including a driving unit equipped with a pair of left and right crawler type traveling devices 1 </ b> A and 1 </ b> B and a driving seat 2 is provided in front of a pre-cutting processing unit 5. While combining the base of the process part frame 5a so that rotation is possible, the threshing apparatus 7 and the grain tank 8 are provided in the rear part of the body frame 4, and the combine is comprised.

  This combine harvests rice, wheat and the like. When the lifting cylinder 6 linked to the pretreatment unit frame 5a is operated, the lifting cylinder 6 moves the pretreatment unit frame 5a up and down with respect to the self-propelled machine body. By swinging, the pre-cutting processing unit 5 is moved up and down into a lowering working state in which the lower end portion of the raising device 5b is located near the ground and a rising non-working state in which the raising device 5b is raised higher from the ground. When the pre-cutting processing unit 5 is in the descending working state and the self-propelled machine is run, the pre-cutting processing unit 5 causes the planted culm to be caused and processed by the device 5b, and the pruning processing is performed by the clipper-shaped cutting device 5c. The harvested cereal from the reaping device 5c is conveyed toward the rear of the machine body by the supply device 5d and supplied to the start end of the threshing feed chain 7a of the threshing device 7. The threshing device 7 supplies the tip side of the harvested cereal cocoon to the handling room (not shown) while carrying the threshing feed chain 7a while holding the stock side of the reaped cereal meal by the threshing feed chain 7a. The grain tank 8 collects and stores the threshed grains from the threshing device 7.

  An engine 3 is provided below the driver's seat 2 of the self-propelled aircraft, and a traveling transmission device that transmits the driving force of the engine 3 to the left traveling device 1A and the right traveling device 1B is configured as shown in FIG.

  That is, the output from the output shaft 3a of the engine 3 is transmitted to the input shaft 11a of the main transmission 11 serving as the input shaft of the transmission case 9 via the belt transmission mechanism 10, and the output shaft of the main transmission 11 is transmitted. 11b is transmitted to the input gear 21 of the auxiliary transmission 20, and the driving force of the main drive shaft 29 comprising the output cylinder shaft of the auxiliary transmission 20 is externally fitted to the main drive shaft 29 so as to be integrally rotatable. Main steering clutch body 33, main left traveling transmission gear 31a configured such that input gear portion 31ai (see FIG. 4) is engaged with and disengaged from one end side of main steering clutch body 33, and this main left traveling transmission gear. The transmission is configured to be transmitted to the drive shaft 1a of the left traveling device 1A via a high speed gear transmission mechanism 40 for left traveling that is linked to the gear 31a by an input gear 41. The driving force of the main drive shaft 29 is configured so that the main steering clutch body 33 and the input gear portion 31bi (see FIG. 4) are engaged and disengaged with the other end side of the main steering clutch body 33. The transmission gear 31b is configured to be transmitted to the drive shaft 1b of the right traveling device 1B via a high speed gear transmission mechanism 50 for right traveling that is linked to the main right traveling transmission gear 31b by an input gear 51.

  A swing clutch 60 formed of a multi-plate friction clutch is provided between one end side of the sub drive shaft 12 that is a support shaft that supports the main drive shaft 29 so as to be relatively rotatable, and the main drive shaft 29. A sub steering clutch body 71 externally fitted to the sub drive shaft 12 so that the driving force of the sub drive shaft 12 when the power is transmitted to the sub drive shaft 12 via the turning clutch 60 is freely rotated. A sub left travel transmission gear 73 configured such that an input gear portion 73a (see FIG. 3) is engaged with and disengaged from one end side of the steering clutch body 71, and a left coupled to the sub left travel transmission gear 73 by an input gear 91. It is configured to transmit to the drive shaft 1a of the left traveling device 1A via the traveling low-speed gear transmission mechanism 90. The sub-right running is configured such that the driving force of the sub-drive shaft 12 is such that the input gear portion 74a (see FIG. 4) is engaged with and disengaged from the sub-steering clutch body 71 and the other end side of the sub-steering clutch body 71. The transmission gear 74 is configured to be transmitted to the drive shaft 1b of the right traveling device 1B via the right traveling low-speed transmission gear mechanism 100 that is linked to the sub-right traveling transmission gear 74 by the input gear 101.

  As shown in FIG. 1, the main transmission 11 is driven by a variable displacement axial plunger type hydraulic pump P having the input shaft 11a as a pump shaft, and pressure oil from the hydraulic pump P. An axial plunger type hydraulic motor M connected to the hydraulic pump P and having the output shaft 11a as a motor shaft is provided. That is, the main transmission 11 converts the driving force from the engine 3 into the forward driving force and the backward driving force by changing the swash plate angle of the hydraulic pump P. The hydrostatic continuously variable transmission is configured to shift in stages and output from the output shaft 11b.

  As clearly shown in FIG. 3, the sub-transmission device 20 includes a small-diameter transmission gear 23 supported on a rotary support shaft 22 that supports the input gear 21 so as to rotate integrally therewith, and the small-diameter transmission gear 23. A meshing clutch 24 provided between the gear 23 and the input gear 21, a large-diameter transmission gear 27 supported relatively rotatably on the rotary support shaft 22, the large-diameter transmission gear 27 and the rotary support shaft 22 A multi-plate friction clutch 26, a low-speed transmission gear 25 meshed with the small-diameter transmission gear 23, a high-speed transmission gear 28 meshed with the large-diameter transmission gear 27, and the low-speed transmission gear 25 at one end. The high-speed transmission gear 28 is provided with the main drive shaft 29 as an output cylindrical shaft provided with the other end side so as to be integrally rotatable.

  The main drive shaft 29 includes a low-speed output cylindrical shaft 25a formed integrally with the low-speed transmission gear 25, a high-speed output cylindrical shaft 28a formed integrally with the high-speed transmission gear 28, and the high-speed output cylindrical shaft 28a and the low-speed output cylindrical shaft 25a. Each of the clutch body holders 29a is also used as a joint that is connected to be integrally rotatable.

  As a result, the small-diameter transmission gear 23 is slid toward the input gear 21, the engagement clutch 24 is operated to be engaged, and the friction clutch 26 is operated to be disengaged. The driving force introduced from the main transmission 11 to the input gear 21 is in a low-speed state so that the driving force is transmitted to the main drive shaft 29 via the meshing clutch 24, the small-diameter transmission gear 23, and the low-speed transmission gear 25. On the other hand, when the mesh clutch 24 is operated in the disengaged state and the friction clutch 26 is operated in the engaged state, the auxiliary transmission 20 uses the driving force introduced from the main transmission 11 to the input gear 21. A high-speed state is established such that the rotation is transmitted to the main drive shaft 29 via the rotary support shaft 22, the friction clutch 26, the large-diameter transmission gear 27, and the high-speed transmission gear 28.

  The main steering clutch body 33 is supported in a state in which the main steering clutch body 33 is engaged with the clutch body holder 29a of the main drive shaft 29 so as to be integrally rotated and slidable by spline engagement. A rod-shaped steering operation body 82 engaged with the outer peripheral side of the main steering clutch body 33 by a fork portion 80 is slidably supported by the mission case 9, and the steering operation body 82 is slidably operated. As a result, the main steering clutch body 33 is slid along the clutch body holder 29a by the fork 80 of the steering operation body 32, and the straight traveling position S shown in FIG. Switching operation is performed between a right turn position R and a left turn position L shown in FIG.

  As shown in FIG. 4, in the main steering clutch body 33 operated to the straight traveling position S, one end side of the main steering clutch body 33 is engaged with the input gear portion 31ai of the main left traveling transmission gear 31a. The intermediate portion of the clutch body 33 is engaged with the clutch body holder 29a of the main drive shaft 29, and the other end side of the main steering clutch body 33 is engaged with the input gear portion 31bi of the main right traveling transmission gear 31b. The driving force of the main drive shaft 29 is transmitted to the main left travel transmission gear 31a and the main right travel transmission gear 31a, and from the main left travel transmission gear 31a to the drive shaft 1a of the left travel device 1A via the high speed gear transmission mechanism 40, The power is transmitted from the main right traveling transmission gear 31b to the drive shaft 1b of the right traveling apparatus 1B via the high speed gear transmission mechanism 50.

  As shown in FIG. 6, the main steering clutch body 33 operated to the left turning position L is such that the entire main steering clutch body 33 is disengaged from the input gear portion 31ai of the main left traveling transmission gear 31a. One end side of the body 33 is engaged with the clutch body holder 29a of the main drive shaft 29, and the other end side of the main steering clutch body 33 is engaged with the input gear portion 31bi of the main right traveling transmission gear 31b. The driving force of the shaft 29 is not transmitted to the driving shaft 1a of the left traveling device 1A, and the driving force of the main driving shaft 29 is driven from the main right traveling transmission gear 31b via the high speed gear transmission mechanism 50 to the driving shaft 1b of the right traveling device 1B. To communicate.

  As shown in FIG. 5, the main steering clutch body 33 operated to the right turn position R has the entire main steering clutch body 33 disengaged from the input portion 31bi of the main right traveling transmission gear 31b. One end side of the body 33 is engaged with the input gear portion 31ai of the main left traveling transmission gear 31a, and the other end side of the main steering clutch body 33 is engaged with the clutch body holder 29a of the main drive shaft 29. The driving force of the shaft 29 is not transmitted to the driving shaft 1b of the right traveling device 1B, but is transmitted from the main left traveling transmission gear 31a to the driving shaft 1a of the left traveling device 1A via the high speed gear transmission mechanism 40.

  As shown in FIG. 3, the sub steering clutch body 71 is supported in a state of being integrally and slidably engaged by a spline engagement with a holder 72 that is attached to the sub drive shaft 12 so as to be integrally rotatable. A fork portion 81 engaged with the outer peripheral side of the auxiliary steering clutch body 71 is provided in the steering operating body 82, and the auxiliary steering clutch body 71 is a main steering clutch body 33 of the steering operating body 82. In conjunction with the sliding operation, the sliding operation is performed by the fork portion 81 of the steering operation body 82, and the operation is switched to a state corresponding to each operation position of the main steering clutch body 33.

  That is, as shown in FIG. 4, when the main steering clutch body 33 is operated to the straight traveling position S, the auxiliary steering clutch body 71 has one end side of the auxiliary steering clutch body 71 input to the auxiliary right traveling transmission gear 74. The auxiliary steering clutch body 71 is engaged with the gear portion 74 a, the intermediate portion of the auxiliary steering clutch body 71 is engaged with the clutch body holder 72 of the auxiliary driving shaft 12, and the other end side of the auxiliary steering clutch body 71 is input to the auxiliary left traveling transmission gear 73. It will be in the state engaged with the gear part 73a.

  As shown in FIG. 6, when the main steering clutch body 33 is operated to the left turning position L, the auxiliary steering clutch body 71 is configured such that the entire auxiliary steering clutch body 71 is an input gear of the auxiliary right traveling transmission gear 74. The one end side of the sub steering clutch body 71 is engaged with the clutch body holder 72 of the sub drive shaft 12, and the other end side of the sub steering clutch body 71 is connected to the input gear portion 73a of the sub left traveling transmission gear 73. The driving force of the sub drive shaft 12 is not transmitted to the drive shaft 1b of the right traveling device 1B, and the driving force of the sub drive shaft 12 is transmitted from the sub left traveling transmission gear 73 to the low speed gear transmission mechanism 90. Via the drive shaft 1a of the left traveling device 1A.

  As shown in FIG. 5, when the main steering clutch body 33 is operated to the right turning position R, the auxiliary steering clutch body 71 is input to the auxiliary left traveling transmission gear 73. The auxiliary steering clutch body 71 is disengaged from the gear portion 73a, and one end side of the auxiliary steering clutch body 71 is engaged with the input gear portion 74a of the auxiliary right traveling transmission gear 74, and the other end side of the auxiliary steering clutch body 71 is the clutch body holder 72 of the auxiliary drive shaft 12. The driving force of the auxiliary drive shaft 12 is not transmitted to the drive shaft 1a of the left traveling device 1A, and the driving force of the auxiliary drive shaft 12 is transmitted from the auxiliary right traveling transmission gear 74 to the low speed gear transmission mechanism 100. Is transmitted to the drive shaft 1b of the right traveling device 1B.

  As shown in FIG. 3, the high-speed gear transmission mechanism 40 for left traveling that links the main left traveling transmission gear 31 a to the drive shaft 1 a of the left traveling apparatus 1 </ b> A meshes with the main left traveling transmission gear 31 a. An input gear 41, a rotary transmission shaft 42 in which the input gear 41 is connected to one end side so as to be integrally rotatable, an intermediate transmission gear 43 which is connected to the other end side of the rotary transmission shaft 42 so as to be integrally rotatable. Each of the final transmission gears 44 is connected to the drive shaft 1a of the left traveling device 1A while being engaged with the transmission gear 43 so as to be integrally rotatable. The high-speed gear transmission mechanism 50 for right traveling, in which the main right traveling transmission gear 31b is interlocked with the drive shaft 1b of the right traveling apparatus 1B, includes the input gear 51 meshed with the main right traveling transmission gear 31b, and this input gear. 51, a rotation transmission cylinder shaft 54 connected to one end side so as to be integrally rotatable, an intermediate transmission gear 52 connected to the other end side of the rotation transmission cylinder shaft 54 so as to be integrally rotatable, and meshed with the intermediate transmission gear 52 In this state, each of the final transmission gears 53 is connected to the drive shaft 1b of the right traveling device 1B so as to be integrally rotatable.

  The left traveling low-speed gear transmission mechanism 90 that links the sub left traveling transmission gear 73 to the drive shaft 1a of the left traveling apparatus 1A includes the input gear 91 meshed with the sub left traveling transmission gear 73, and the input gear. The rotation transmission shaft 42 is connected to the rotation transmission shaft 42, the intermediate transmission gear 43 is connected to the rotation transmission shaft 42, and the final transmission gear 44 is meshed with the intermediate transmission gear 43. It is prepared.

  The right traveling low-speed gear transmission mechanism 100 that links the sub right traveling transmission gear 74 to the drive shaft 1b of the right traveling apparatus 1B includes the input gear 101 meshed with the subsidiary right traveling transmission gear 74, and the input gear. The intermediate transmission gear 52 is connected to the intermediate transmission gear 52, and the final transmission gear 53 is engaged with the intermediate transmission gear 52.

  The left-side traveling device 1A and the right-side traveling high-speed gear transmission mechanism 40 and the right-side traveling high-speed gear transmission mechanism 50 are connected to the left traveling device 1A and the right traveling if the rotation speeds of the main left traveling transmission gear 31a and the main right traveling transmission gear 31b are the same. The high-speed gear transmission mechanism 40 for left travel and the high-speed gear transmission mechanism 50 for right travel are provided with the same reduction gear ratio so that power is transmitted to the state where the drive speed of the device 1B is the same. The left traveling low-speed gear transmission mechanism 90 and the right traveling low-speed gear transmission mechanism 100 have the left traveling device 1A and the right traveling as long as the sub left traveling transmission gear 73 and the sub right traveling transmission gear 74 have the same rotational speed. The low-speed gear transmission mechanism 90 for left travel and the low-speed gear transmission mechanism 100 for right travel are provided with the same reduction gear ratio so that power is transmitted in a state where the drive speed of the device 1B is the same. If the rotational speeds of the main drive shaft 29 and the sub drive shaft 12 are the same, power is transmitted from the sub drive shaft 12 to the drive shafts 1a and 1b via the low speed gear transmission mechanisms 90 and 100 to drive the travel devices 1A and 1B. When the traveling devices 1A and 1B are driven, the driving speed of the traveling devices 1A and 1B is transmitted from the main drive shaft 29 to the drive shafts 1a and 1b through the high-speed gear transmission mechanisms 40 and 50 to drive the traveling devices 1A and 1B. The reduction ratios of the two low-speed gear transmission mechanisms 90 and 100 are set larger than the reduction ratios of the two high-speed gear transmission mechanisms 40 and 50 so as to be lower than the drive speeds of 1A and 1B.

  That is, as shown in FIG. 9, the input gear portions 31ai and 31bi of the main left traveling transmission gear 31a and the main right traveling transmission gear 31b are connected to gears equivalent to 20 teeth (the main left traveling transmission gear 31a and the main right traveling transmission gear. (If there is no gear drop between the input gear portions 31ai and 31bi of 31b and the main steering clutch body 33 to provide meshing accommodation in the main steering clutch body rotation direction, the gear becomes 20 teeth). The gear portion meshing with the input gears 41 and 51 of the main left traveling transmission gear 31a and the main right traveling transmission gear 31b is configured as a 30-tooth gear, and the input gear 41 of each of the high-speed gear transmission mechanisms 40 and 50, 51 is a 36-tooth gear. The input gear portions 73a and 74a of the sub left travel transmission gear 73 and the sub right travel transmission gear 74 are replaced with gears equivalent to 16 teeth (the input gear portions 73a and 74a of the sub left travel transmission gear 73 and the sub right travel transmission gear 74 and If no gear drop is provided between the auxiliary steering clutch body 71 and the auxiliary steering clutch body in the rotational direction thereof, the auxiliary left driving transmission gear 73 is configured. And the gear part which meshes with the input gears 91 and 101 of the sub right traveling transmission gear 74 is configured as a 16-tooth gear, and the input gears 91 and 101 of the low-speed gear transmission mechanisms 90 and 100 are configured as 48-tooth gears. It is.

  As shown in FIGS. 2 and 3, a turning brake 61 is provided at one end portion of the auxiliary drive shaft 12, and when the turning brake 61 is operated to be in the on state, a friction braking force is applied to the auxiliary drive shaft 12. Thus, the brake is applied to the drive shaft 1a of the left traveling device 1A via the auxiliary steering clutch body 71, the auxiliary left traveling transmission gear 73, and the low speed gear transmission mechanism 90, and the auxiliary steering clutch body 71, the auxiliary right traveling transmission gear is applied. 74. A brake is applied to the drive shaft 1b of the right traveling device 1B via the low speed gear transmission mechanism 100.

  That is, this travel transmission device can perform a steering operation so that the self-propelled machine body travels straight or turns by slidingly operating the steering operation body 82 and switching the swing clutch 60 and the swing brake 61. It can be done.

  That is, the steering operation body 82 is slid and operated to the neutral position N (see FIG. 3). Then, the steering operation body 82 operates the main steering clutch body 33 to the rectilinear position S by the fork portion 80, and the driving force of the main drive shaft 29 is changed to the main steering clutch body 33, the main left traveling transmission gear 31a, and the high speed gear. The drive force of the main drive shaft 29 is applied to the drive shaft 1a of the left traveling device 1A via the transmission mechanism 40, and the right driving is performed via the main steering clutch body 33, the main right travel transmission gear 31b, and the high speed gear transmission mechanism 50. Each is transmitted to the drive shaft 1b of the device 1B. At this time, the steering operating body 82 is interlocked with the operation of the main steering clutch body 33, and the sub steering clutch body 71 is moved to the sub left traveling transmission gear 73, the clutch body holder 71, and the sub right traveling transmission gear 74 by the fork portion 81. To the drive shaft 1a of the left traveling device 1A via the sub steering clutch body 71, the sub left traveling transmission gear 73, the low speed gear transmission mechanism 90, and the sub driving shaft 12 The drive shaft 12 is interlocked with the drive shaft 1b of the right traveling device 1B via the sub steering clutch body 71, the sub right traveling transmission gear 74, and the low speed gear transmission mechanism 100, but the swing clutch 60 and the swing brake 61 are disconnected. If it is operated to the state, the auxiliary drive shaft 12 enters the idle state. As a result, the left and right traveling apparatuses 1A and 1B are driven at the same driving speed by the driving force transmitted from the main drive shaft 29 via the high-speed gear transmission mechanisms 40 and 50, and the self-propelled aircraft travels straight ahead.

  When the steering operation body 82 is operated to the left turning position LT (see FIG. 3), the steering operation body 82 operates the main steering clutch body 33 to the left turning position L by the fork portion 80, and the main drive shaft 29. The driving force is transmitted to the driving shaft 1b of the right traveling device 1B via the main steering clutch body 33, the main right traveling transmission gear 31b, and the high speed gear transmission mechanism 50, but the driving force of the main driving shaft 29 is traveling on the main left traveling. It is not transmitted to the transmission gear 31a. At this time, the steering operation body 32 engages the sub steering clutch body 71 with the sub left traveling transmission gear 73 and the clutch body holder 72 in conjunction with the operation of the main steering clutch body 33 and the sub right traveling transmission gear 74. The sub drive shaft 12 is interlocked with the drive shaft 1b of the left traveling device 1B via the sub steering clutch body 71, the sub left traveling transmission gear 73, and the low speed gear transmission mechanism 90. At this time, if the turning clutch 60 is in the engaged state, the driving force of the main drive shaft 29 is transmitted to the auxiliary drive shaft 12 via the turning clutch 60, and the driving force of the auxiliary drive shaft 12 is left side travel device 1A. Is transmitted to the drive shaft 1a. When the turning clutch 60 is in the disengaged state, the sub drive shaft 12 is in an idle state, and no power is transmitted to the drive shaft 1a of the left traveling device 1A. When the turning brake 61 is in the engaged state, the sub drive shaft 12 is braked by the turning brake 61 and the drive shaft 1a of the left traveling device 1A is braked.

  Thus, when the steering operation body 82 is operated to the left turning position LT and the turning clutch 60 and the turning brake 61 are turned off, the right traveling device 1B transmits from the main drive shaft 29 via the high speed gear transmission mechanism 50. The left traveling device 1A is in a state where transmission is stopped by the generated driving force, and the self-propelled aircraft is turned left at a turning radius determined by driving the right traveling device 1B and stopping the left traveling device 1A. Make a turn.

  When the steering operation body 82 is operated to the left turning position LT and the turning clutch 60 is turned on, the right traveling apparatus 1B is driven by the driving force transmitted from the main drive shaft 29 via the high speed gear transmission mechanism 50. The left traveling device 1A is driven at a lower speed than the right traveling device 1B by the driving force transmitted from the auxiliary drive shaft 12 through the low speed gear transmission mechanism 90, and the self-propelled aircraft is traveling left and right. The vehicle turns leftward with a relatively large turning radius determined by the difference in driving speed between the devices 1A and 1B.

  When the steering operation body 82 is operated to the left turning position LT and the turning brake 61 is turned on, the right traveling apparatus 1B is driven by the driving force transmitted from the main drive shaft 29 via the high speed gear transmission mechanism 50. The left traveling device 1A is braked by the turning brake 61, and the self-propelled vehicle is braked leftward with a relatively small turning radius determined by the driving of the right traveling device 1B and the braking of the left traveling device 1A. Make a turn.

  When the steering operation body 82 is operated to the right turning position RT (see FIG. 3), the steering operation body 82 operates the main steering clutch body 33 to the right turning position R by the fork unit 80, and the main drive shaft. 29 is transmitted to the drive shaft 1a of the left traveling device 1A via the main steering clutch body 33, the main left traveling transmission gear 31a, and the high speed gear transmission mechanism 40. The driving force of the main driving shaft 29 is the main driving force. It is not transmitted to the right traveling transmission gear 31b. At this time, the steering operation body 82 is engaged with the operation of the main steering clutch body 33 to engage the sub steering clutch body 71 with the sub right traveling transmission gear 74 and the clutch body holder 72 and the sub left traveling transmission gear 73. The auxiliary drive shaft 12 is interlocked with the drive shaft 1a of the right traveling device 1A via the auxiliary steering clutch body 71, the auxiliary right traveling transmission gear 74, and the low speed gear transmission mechanism 100. At this time, if the turning clutch 60 is in the engaged state, the driving force of the main drive shaft 29 is transmitted to the auxiliary drive shaft 12 via the turning clutch 60, and the driving force of the auxiliary drive shaft 12 is transmitted to the right traveling device 1B. Is transmitted to the drive shaft 1b. When the turning clutch 60 is in the disengaged state, the sub drive shaft 12 enters the idle state, and no power is transmitted from the sub drive shaft 12 to the drive shaft 1b of the right traveling device 1B. When the turning brake 61 is in the engaged state, the auxiliary drive shaft 12 is braked by the turning brake 61 and the drive shaft 1b of the right traveling device 1B is braked.

  As a result, when the steering operating body 82 is operated to the right turning position RT and the turning clutch 60 and the turning brake 61 are turned off, the left traveling device 1a is moved from the main drive shaft 29 via the high speed gear transmission mechanism 40. Driven by the transmitted driving force, the right traveling device 1B is in a state where transmission is stopped, and the self-propelled vehicle body turns right with a turning radius determined by driving the left traveling device 1A and stopping the right traveling device 1B. Make a turn.

  When the steering operation body 82 is operated to the right turning position R and the turning clutch 60 is turned on, the left traveling device 1A is driven by the driving force transmitted from the main drive shaft 29 via the high speed gear transmission mechanism 40. The right traveling device 1B is driven at a lower speed than the left traveling device 1A by the driving force transmitted from the auxiliary drive shaft 12 through the low speed gear transmission mechanism 100, and the self-propelled aircraft is left and right. The vehicle travels to the right with a relatively large turning radius determined by the difference in driving speed between the traveling devices 1A and 1B.

  When the steering operation body 82 is operated to the right turning position R and the turning brake 61 is turned on, the left traveling device 1A is driven by the driving force transmitted from the main drive shaft 29 via the high speed gear transmission mechanism 40. The right traveling device 1B is braked by the turning brake 61, and the self-propelled vehicle body moves to the right with a relatively small turning radius determined by the driving of the left traveling device 1A and the braking of the right traveling device 1B. Brake turns.

  As shown in FIG. 4, the main steering clutch body 33 is connected to the input gear portions 31ai and 31bi of the main left traveling transmission gear 31a and the main right traveling transmission gear 31b in a state where the main steering clutch body 33 is in the straight traveling position S. The engagement length A in the sliding direction of the main steering clutch body to be engaged is set such that the sub steering clutch body 71 is connected to the sub left traveling transmission gear 73 and the sub driving gear 73 in a state where the main steering clutch body 33 is in the straight traveling position S. It is longer than the engagement length B in the sliding direction of the sub steering clutch body that engages with the input gear portions 73a and 74a of the right traveling transmission gear 74.

  As shown in FIG. 9, meshing interchange in the rotational direction of the main steering clutch body between the input gear portions 31ai and 31bi of the main left traveling transmission gear 31a and the main right traveling transmission gear 31b and the main steering clutch body 33. Each input gear portion 31ai, 31bi and the main steering clutch body 33 are configured as gears having a tooth drop structure as shown in FIG. 9 so as to provide S1. Each of the sub left travel transmission gear 73 and the sub right travel transmission gear 74 is provided with a meshing interchange S2 in the rotation direction of the sub steering clutch body between the input gear portions 73a, 74a of the sub right driving transmission gear 74 and the sub steering clutch body 71. The input gear portions 73a and 74a and the auxiliary steering clutch body 71 are configured as a gear having a tooth drop structure as shown in FIG.

  The high-speed gear interlocking mechanisms 40, 50 and the low-speed gear interlocking mechanisms 90, 100 interlock the main traveling transmission gears 31a, 31b and the auxiliary traveling transmission gears 73, 74, and the high-speed gear interlocking mechanisms 40, 50 and the low-speed gear interlocking mechanisms Since the gear interlocking mechanisms 90 and 100 are provided with the reduction transmission ratio, the main traveling transmission gears 31a and 31b and the auxiliary traveling transmission gears 73 and 74 are rotated during one rotation of the main traveling transmission gears 31a and 31b. The sub-travel transmission gears 73 and 74 are in an interlocked state in which the sub-travel transmission gears 73 and 74 rotate approximately twice. As a result, as shown in FIG. 9, the mesh accommodation S2 between the input gear portions 73a and 74a of the sub left traveling transmission gear 73 and the sub main right traveling transmission gear 74 and the sub steering clutch body 71 is It is larger than the meshing accommodation S1 between the input gear portions 31ai and 31bi of the left traveling transmission gear 31a and the main right traveling transmission gear 31b and the main steering clutch body 33.

  That is, as shown in FIG. 7 as an example, the state of the main steering clutch body 33 and the sub steering clutch body 71 in the middle of the switching operation of the main steering clutch body 33 from the right turn position R to the straight advance position S. When the main steering clutch body 33 is switched from the right turning position R or the left turning position L to the straight movement position S, the auxiliary steering clutch body 71 is also operated in conjunction with the main steering clutch body 33. Due to the difference between the engagement length A of the main steering clutch body 33 and the engagement length B of the auxiliary steering clutch body 71, the main steering clutch body 33 is first driven by the main right traveling transmission gear 31a or the main left traveling gear 31a. Engagement with the input gear portions 31ai and 31bi of the transmission gear 31b, after which the auxiliary steering clutch body 71 engages with the input gear portions 73a and 74b of the auxiliary left running transmission gear 73 or the auxiliary right running transmission gear 74. The difference in timing will appear Both the main steering clutch body 33 and the sub steering clutch body 71 are engaged with the main left travel transmission gear 31a, the main right travel transmission gear 31b, the sub left travel transmission gear 73, and the sub right travel transmission gear 74 as the gears to be engaged. The engaging operation is performed so as to facilitate the operation. Further, when the main steering clutch body 33 is engaged with the input gear portions 31bi and 31ai of the main right traveling transmission gear 31b and the main left traveling transmission gear 31a, the main steering clutch body 33 is caused by the action of the meshing accommodation S1. And the main left travel transmission gear 31b and the main left travel transmission gear 31a are engaged so as to be easily aligned in the rotational direction so that the sub steering clutch body 71 is driven to the sub right travel. When engaging the transmission gear 74 and the sub-left travel transmission gear 73, the sub steering clutch body 71 and the sub-right travel transmission gear 74 and the sub-left travel transmission gear 73 are engaged by the action of the meshing accommodation S2. Engagement operation is performed so as to facilitate the alignment in the rotational direction for fitting.

  The rotational phase of the sub steering clutch body 71 in which the sub steering clutch body 71 engages with the sub left traveling transmission gear 73 in a freely transmitting manner, and the sub steering clutch body 71 is transmitted to the sub right traveling transmission gear 74. The gears are assembled in an initial setting relationship in which the rotational phase of the sub-steering clutch body 71 that is freely engaged is shifted by 45 degrees, and the main operation clutch body 33 is moved from the left turning position L or the right turning position R. When the operation is switched to the rectilinear position S, the main steering clutch body 33 is engaged with the input gear portions 31ai and 31bi of the main left traveling transmission gear 31a and the main right traveling transmission gear 31b as lightly as possible.

  That is, FIG. 8 shows the rotational phase of the sub steering clutch body 71 in which the sub steering clutch body 71 is engaged with the sub left traveling transmission gear 73, and the sub steering clutch body 71 is engaged in the sub right traveling transmission gear 74. FIG. 8A shows the state of each gear when the gears are assembled in an initial setting relationship in which there is no deviation from the rotational phase of the auxiliary steering clutch body 71. FIG. The input gear portion 31ai of the gear 31a, the main steering clutch body 33, the input gear portion 31bi of the main right traveling transmission gear 31b, the input gear portion 73a of the auxiliary left traveling transmission gear 73, and the input gear portion 74a of the auxiliary right traveling transmission gear 74. Shows the state. In FIG. 8B, the main steering clutch body 33 is switched from the right turning position R to the straight movement position S, and the main steering clutch body 33 is connected to the input gear portion 31bi of the main right traveling transmission gear 31b. When the direction clutch body 71 starts to engage with the input gear portion 73a of the sub left travel transmission gear 73, the engagement protrusion 33T of the main steering clutch body 33 is engaged with the engagement protrusion of the main right travel transmission gear 31b. Positioned on the upper side in the main steering clutch body rotation direction with respect to 31T, the engagement protrusion 33T of the main steering clutch body 33 is a transmission surface on the lower side of the main steering clutch body rotation direction of the engagement protrusion 33T. The state of each gear when engaged in a state of contact with the engagement protrusion 31T of the main right traveling transmission gear 31b (hereinafter referred to as a front engagement state) is shown. In FIG. 8C, the main steering clutch body 33 is switched from the right turning position R to the straight movement position S, and the main steering clutch body 33 is moved to the input gear portion 31bi of the main right traveling transmission gear 31b. When the direction clutch body 71 starts to engage with the input gear portion 73a of the sub left travel transmission gear 73, the engagement protrusion 33T of the main steering clutch body 33 is engaged with the engagement protrusion of the main right travel transmission gear 31b. Positioned on the lower side in the main steering clutch body rotation direction with respect to 31T, the engagement protrusion 33T of the main steering clutch body 33 is a transmission surface on the upper side of the main steering clutch body rotation direction of the engagement protrusion 33T. The state of each gear when engaged in a state of contact with the engagement protrusion 31T of the main right traveling transmission gear 31b (hereinafter referred to as a back engagement state) is shown. In FIG. 8D, the main steering clutch body 33 is engaged with the main right traveling transmission gear 31b in a back-engaged state, and the sub left traveling transmission gear 73 is connected from the main drive shaft 29 to the high speed gear transmission mechanism 40 and the low speed gear. The state of each gear when rotated by the driving force transmitted via the transmission mechanism 90 is shown.

  9 shows the rotational phase of the sub steering clutch body 71 in which the sub steering clutch body 71 is engaged with the sub left driving transmission gear 73, and the sub phase in which the sub steering clutch body 71 is engaged with the sub right driving transmission gear 74. FIG. 9 (a) shows the state of each gear when the gears are assembled in an initial setting relationship with a 45 degree deviation from the rotational phase of the steering clutch body 71. FIG. The input gear portion 31ai of the left travel transmission gear 31a, the main steering clutch body 33, the input gear portion 31bi of the main right travel transmission gear 31b, the input gear portion 73a of the sub left travel transmission gear 73, and the input of the sub right travel transmission gear 74 The state of the gear part 74a is shown. In FIG. 9B, the main steering clutch body 33 is switched from the right turning position R to the straight traveling position S, and the main steering clutch body 33 is engaged with the input gear portion 31bi of the main right traveling transmission gear 31b. The state of each gear when engaged in a state is shown. In FIG. 9C, the main steering clutch body 33 is switched from the right turning position R to the straight traveling position S, and the main steering clutch body 33 is reversely engaged with the input gear portion 31bi of the main right traveling transmission gear 31b. The state of each gear when engaged in a state is shown. 9 (D) shows that the main steering clutch body 33 is engaged with the main right traveling transmission gear 31b in the reverse engagement state, and the sub left traveling transmission gear 73 is connected from the main drive shaft 29 to the high speed gear transmission mechanism 40 and the low speed gear. The state of each gear when rotated by the driving force transmitted through the transmission mechanism 90 is shown.

  That is, the rotational phase of the sub steering clutch body 71 with which the sub steering clutch body 71 engages with the sub left traveling transmission gear 73 and the sub steering with which the sub steering clutch body 71 engages with the sub right traveling transmission gear 74. When the gears are assembled in an initial setting with no deviation from the rotational phase of the clutch body 71, the main steering clutch body 33 that is switched from the right turn position R to the straight drive position S is the main right travel transmission gear. When engaged with 31b in the reverse engagement state, power is transmitted from the main drive shaft 29 to the sub left traveling transmission gear 73 via the high speed gear transmission mechanism 40 and the low speed gear transmission mechanism 90, and the sub left traveling transmission gear 73 is Although driven, the engaging projection 73T of the sub left traveling transmission gear 73 contacts the engaging projection 71T of the sub steering clutch body 71, and the driving force of the sub left traveling transmission gear 73 is changed to the sub steering clutch body 71, Right travel transmission gear 74, low speed gear for right travel A main steering clutch body 33 for rotation of the main right traveling transmission gear 31b, which is transmitted to the main right traveling transmission gear 31b through the transmission mechanism 100 and the high speed gear transmission mechanism 50 for right traveling; Friction with the input gear portion 31bi of the main right traveling transmission gear 31b is increased, and the operating force for engaging and operating the main steering clutch body 33 to the main right traveling transmission gear 31b to a predetermined engagement length. Becomes heavier.

  On the other hand, the rotational phase of the sub steering clutch body 71 in which the sub steering clutch body 71 engages with the sub left traveling transmission gear 73 and the sub phase in which the sub steering clutch body 71 engages with the sub right traveling transmission gear 74. The main steering clutch body that is switched from the right-turn position R to the straight-forward position S when the gears are assembled in an initial relationship in which the rotational phase of the steering clutch body 71 is offset by 45 degrees. Even if 33 is engaged with the main right traveling transmission gear 31b in the reverse engagement state, it is transmitted from the main drive shaft 29 via the left traveling high speed gear transmission mechanism 40 and the left traveling low speed gear transmission mechanism 90. The engaging protrusion 73T of the rotating sub-left traveling transmission gear 73 does not contact the engaging protrusion 71T of the auxiliary steering clutch body 71, and the driving force of the auxiliary left traveling transmission gear 73 is controlled by the auxiliary steering clutch body 71 and the auxiliary steering clutch body 71. Right traveling transmission gear 74, right traveling low speed gear transmission mechanism 100, It is not transmitted to the main right traveling transmission gear 31b via the traveling high-speed gear transmission mechanism 50, whereby the main right traveling transmission gear 31b is not rotated, and the main steering clutch body 33 and the main right traveling transmission gear Strong friction with the input gear portion 31bi of 31b is unlikely to occur, and the main steering clutch body 33 can be lightly engaged so as to engage with the main right traveling transmission gear 31b to a predetermined engagement length.

  8 and 9 show examples of the state of each gear when the main steering clutch body 33 is switched from the right turning position R to the straight movement position L. The main steering clutch body 33 is shown as an example. The same applies to the case where the main steering clutch body 33 is switched from the left turning position L to the straight position S.

As shown in FIG. 3 and the like, a hydraulic piston 84 and a return spring 83 are provided at one end of the steering operation body 82, and the hydraulic piston 84 is operated by electromagnetic switching valves 85 and 86 shown in FIG. The steering operation body 82 is configured to slide to the neutral position N, the right turn position RT, and the left turn position LT.
The multi-plate friction clutch 26 of the auxiliary transmission 20 is provided with a hydraulic piston 26a, and this hydraulic piston 26a is operated by an electromagnetic switching valve 26b shown in FIG. is there.
A hydraulic piston 63 is installed in the swing clutch 60, and a hydraulic piston 64 is installed in the swing brake 61. The hydraulic piston 63 and the hydraulic piston 64 are operated by the hydraulic operation device shown in FIG. Are configured to be switched.
The turning assist clutch 62 shown in FIGS. 2 and 3 transmits the driving force of the traveling devices 1A and 1B outside the turning to the traveling devices 1B and 1A inside the turning to suppress sudden turning at the beginning of turning. The turning assist clutch 62 is switched by a hydraulic piston 65 shown in FIGS.

  FIG. 11 shows a mission case 9 having another implementation structure. In this mission case 9, the final transmission gears 53 and 44 of the pair of split cases 9a and 9b constituting the mission case 9 are provided. A shield wall 9c disposed below the final gears 53 and 44 is provided inside the split case 9a, and the shield wall 9c is subjected to a stirring action by each gear such as the final transmission gears 53 and 44. The bottom of the transmission case is shielded so as not to reach the lubricating oil staying at the bottom of the case. Thereby, by extracting the lubricating oil from the lower part than the shielding wall 9c in the transmission case, this lubricating oil can be supplied to each hydraulic actuator as a working oil in a state where it is difficult for air to be sucked.

Combine side view Travel transmission device diagram Cross section inside the mission case Sectional drawing in the arrangement part of the main steering clutch body and the sub steering clutch body in the mission case Sectional drawing in the arrangement part of the main steering clutch body and the sub steering clutch body in the mission case Sectional drawing in the arrangement part of the main steering clutch body and the sub steering clutch body in the mission case Sectional view in the middle of switching of main steering clutch body Explanatory drawing of the meshing state in the comparison structure of the main steering clutch body and the sub steering clutch body Explanatory drawing of the meshing state of the main steering clutch body and the sub steering clutch body Hydraulic circuit diagram Sectional view of the bottom of the mission case with a different implementation structure

Explanation of symbols

1A Left travel device 1B Right travel device 12 Sub drive shaft 29 Main drive shaft 31a Main left travel transmission gear 31b Main right travel transmission gear 33 Main steering clutch body 40, 50 High speed gear transmission mechanism 60 Swing clutch 71 Sub steering clutch body 73 Sub left travel transmission gear 74 Sub right travel transmission gear 82 Steering operation body A Main steering clutch body engagement length B Sub steering clutch body engagement length S Main steering clutch body rectilinear position L Main Left turning position R of the steering clutch body R Right turning position of the main steering clutch body S1 Engagement accommodation of the main steering clutch body S2 Engagement accommodation of the auxiliary steering clutch body

Claims (4)

A main drive shaft and a sub drive shaft transmitted via a swing clutch are provided so as to be relatively rotatable,
A main left traveling transmission gear linked to the left traveling device via a high speed gear transmission mechanism, a main right traveling transmission gear linked to the right traveling device via a high speed gear transmission mechanism, and integral rotation and sliding on the main drive shaft A main steering clutch body that is freely supported and detachable from the main left traveling transmission gear and the main right traveling transmission gear;
A sub-left travel transmission gear linked to the left travel device via a low-speed gear transmission mechanism; a sub-right travel transmission gear linked to the right travel device via a low-speed gear transmission mechanism; A sub-steering clutch body that is slidably supported and detachably engageable with the sub-left travel transmission gear and the sub-right travel transmission gear;
When the main steering clutch body is in a rectilinear position engaged with the main left travel transmission gear and the main right travel transmission gear, the sub steering clutch body is connected to the sub left travel transmission gear and the sub right travel transmission gear. When the main steering clutch body engages with the main left traveling transmission gear and enters the right turning position in which the main steering clutch body is disengaged from the main right traveling transmission gear, the sub steering clutch body is moved to the sub steering clutch body. The left steering gear is disengaged and engaged with the sub-right travel transmission gear, and the main steering clutch body is disengaged from the main left travel transmission gear and is engaged with the main right travel transmission gear. When in the turning position, the main steering clutch body and the sub steering clutch body so that the sub steering clutch body engages with the sub left traveling transmission gear and is disengaged from the sub right traveling transmission gear. And the ream Work vehicle traveling transmission apparatus that is provided with a steering operating tool sliding operation by.   Engagement in the sliding direction of the main steering clutch body in which the main steering clutch body is engaged with the main left traveling transmission gear and the main right traveling transmission gear in a state where the main steering clutch body is in the straight traveling position. The auxiliary steering clutch body slide is engaged with the auxiliary left traveling transmission gear and the auxiliary right traveling transmission gear in a state in which the main steering clutch body is in the rectilinear position. The traveling transmission device for a work vehicle according to claim 1, wherein the traveling transmission device is longer than an engagement length in a moving direction.   The auxiliary steering clutch body, the auxiliary left traveling transmission gear, and the auxiliary right traveling transmission gear are engaged in meshing in the rotational direction of the auxiliary steering clutch body, the main steering clutch body, and the main left traveling transmission. 3. The traveling transmission device for a work vehicle according to claim 1 or 2, wherein the gear transmission and the main right traveling transmission gear are set to be larger than the meshing interchange in the main steering clutch body rotation direction. The rotational phase of the sub steering clutch body in which the sub steering clutch body engages freely with the sub left traveling transmission gear, and the sub steering clutch body transmits to the sub right traveling transmission gear. 4. The traveling transmission device for a work vehicle according to claim 3, wherein a rotational phase of the sub steering clutch body that is freely engaged is different.

Images