JP2002349600A - Power transmission controller for working vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simplify a structure for a clutch for a turn-driving system brought into a non-operated condition in a neutral position of a gear transmission in a travel-driving system, in a working vehicle provided with the travel-driving system for driving left and right wheels unidirectionally and the turn-driving system for driving the wheels to generate relative rotational difference between them. SOLUTION: The clutch 50 is constituted to be brought into an operated or the non-operated condition by a spring, and operation members 74, 75, 77 for the clutch and a movable member 79 interlocked with an operation of the gear transmission are engaged via cam means 78, 79a in which the engagement is maintained by the spring to bring the clutch into the non-operated condition in the neutral position of the gear transmission.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention comprises a traveling drive system for driving left and right axles in the same direction, and a turning drive system for driving left and right axles to cause a relative rotation difference between the left and right axles. In a work vehicle provided with a gear transmission having a neutral position in a traveling drive system and a clutch provided in a turning drive system, the present invention relates to a power transmission control device for disabling the clutch in a neutral position in the gear transmission. Things.

[0002]

2. Description of the Related Art In a work vehicle as described above, even when the vehicle is stopped with a gear-type transmission in a traveling drive system in a neutral position, a worker unexpectedly puts his hand on a steering operation tool to turn the vehicle. It is known to operate the system to prevent the vehicle from turning, as disclosed in JP-A-2000-71818. In this publication,
The clutch in the turning drive system is configured to have two sets of gear trains in correspondence with the fact that the gear type transmission in the traveling drive system has a neutral position and two shift operation positions, The shift member of the clutch-type transmission and the shift member of the clutch are interlocked with each other to operate one gear train and another gear train of the clutch at one shift operation position and another shift operation position of the gear transmission. The clutch is deactivated at the neutral position of the gear type transmission.

[0003] Therefore, the above publication complicates the structure of the clutch in the turning drive system. Further, when the gear type transmission in the traveling drive system has three or more shift operation positions, the structure disclosed in this publication cannot cope with the problem.

Therefore, the present invention can simplify the structure of the clutch in the turning drive system, and can cope with the case where the gear type transmission in the traveling drive system has three or more shift operation positions. It is an object of the present invention to provide a new power transmission control device for a work vehicle.

[0005]

SUMMARY OF THE INVENTION A power transmission control device according to the present invention is configured such that a traveling drive system that drives left and right axles (17L, 17R) in the same direction and a left and right axle cause a relative rotation difference between the left and right axles. A traveling drive system, and a gear type transmission (26) having a neutral position in the traveling drive system.
In a work vehicle provided with a clutch (50) in a turning drive system, the clutch (50) is configured to be switched between an operating state and a non-operating state by a spring (48), and the clutch is operated against the spring. The operating means (74, 75, 77) is provided, and the operating member and the movable member (79) interlocked with the operation of the gear type transmission (26) are engaged with the cam means by the spring. Wherein the clutch is engaged via cam means (78, 79a) for disabling the clutch at the neutral position of the gear type transmission.

According to the present invention, the clutch of the turning drive system can be switched between an operating state and a non-operating state by a spring, and an operating member of the clutch and a movable member interlocked with the operation of the gear type transmission are operated by the spring. Since the engagement is maintained via the cam means for maintaining the engagement and disengaging the clutch at the neutral position of the gear type transmission, the clutch is disengaged as described in Japanese Patent Application Laid-Open No. 2000-71818. The clutch does not need to be configured to have two sets of gear trains corresponding to the two shift operation positions of the transmission, and the clutch can be switched between the active state and the inactive state by a single member shift as usual, The structure of the clutch is simplified. Since the cam means is maintained engaged by a spring that activates or deactivates the clutch, there is no need to provide an extra spring. Further, even when the gear type transmission has three or more shift operation positions, it can be dealt with without difficulty by configuring the cam means correspondingly.

[0007] Other features and advantages of the present invention will be apparent from the following description with reference to the drawings.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The illustrated embodiment relates to an embodiment in which the present invention is implemented in a combine. In FIGS. The engine 2 is installed outside the transmission case 1, and the input shaft 3 of the transmission case 1 is
, Via the belt transmission mechanism 4. A drive case 5 is mounted on an upper outer surface of the transmission case 1, and a hydraulic pump 6 and a hydraulic motor 7 constituting a hydraulic drive of a traveling drive system and a hydraulic drive of a turning drive system are provided in the drive case 5. , A hydraulic pump 8 and a hydraulic motor 9 are provided. Pump shafts 10 and 11 of hydraulic pumps 6 and 8
Are inserted into the transmission case 1 and the pump shafts 10,
11 and the common gear 1 on the input shaft 3
4 is engaged. The motor shafts 15, 16 of the hydraulic motors 7, 9 also protrude into the transmission case 1.

The combine shown in the figure has left and right axles 17L, 1
Left and right crawler drive wheels 18L, 18 mounted on the 7R end
R is driven in the same direction to cause the vehicle to travel, and the vehicle is turned by giving a relative rotation difference to the left and right crawler drive wheels 18L and 18R. Left and right planetary gear mechanisms 20L and 20R are provided by fixing left and right carriers 19L and 19R to left and right axles 17L and 17R. Each of the planetary gear mechanisms 20L and 20R has a central sun gear 21L and 21R as usual. The sun gear 21L, 21
Internal gear 22L disposed radially outward of R,
22R, and a plurality of planetary gears 23L, 23R rotatably supported by the carriers 19L, 19R and engaged with the sun gears 21L, 21R and the internal gears 22L, 22R. And the motor shaft 15
A transmission S of a traveling drive system from the motor shaft 16 to the left and right planetary gear mechanisms 20L and 20R and a transmission T of a swing drive system from the motor shaft 16 to the left and right planetary gear mechanisms 20L and 20R are installed in the transmission case 1. I have.

The configuration of the traveling system transmission S will be described with reference to FIGS. 1-4. A gear is provided between a drive shaft 24 concentrically connected to the motor shaft 15 and connected to the motor shaft 15 and a transmission shaft 25 disposed therebelow. An automatic transmission 26 is provided. A parking brake 30 is disposed at one end of a brake shaft 29 which is disposed below the transmission shaft 25 and is connected to the transmission shaft 25 by gears 27 and 28. Furthermore, the gears 31 and 3 are disposed below the brake shaft 29 and
2, a pair of right and left small-diameter gears 34L, 34R fixed to the transmission shaft 33.
Is engaged with the large-diameter gears 35L, 35R formed on the outer peripheral surfaces of the left and right internal gears 22L, 22R loosely fitted to the boss portions of the left and right carriers 19L, 19R, so that the traveling driving force is adjusted. Internal gear 22L, 22
R is to be input.

The gear type transmission 26 has a drive shaft 2
The two gears 38 and 39 loosely fitted to the transmission shaft 25 mesh with the two gears 36 and 37 fixed to
A clutch that couples a high-speed gear 38 when slid and displaced to one side from the illustrated neutral position and a low-speed gear 39 when slid and displaced from the neutral position to the transmission shaft 25, respectively. The slider 40 is provided to perform two-stage shifting.

Next, the structure of the turning drive system transmission T will be described with reference to FIGS. 1, 2 and 5 and 6. A torque detection shaft 41 which is arranged concentrically with the motor shaft 16 and is connected to the motor shaft 16 has a gear. The brake 42 is fixedly installed and a brake 43 for reducing or increasing the braking force on the torque detection shaft 41 according to the magnitude of the transmission torque detected by a cam mechanism (not shown). When the hydraulic pump 8 is in the neutral position by a steering operation tool (not shown), the brake 43 causes a slight output to the motor shaft 16 when an operator unexpectedly touches the steering operation tool. In this case, the torque detection shaft 41 is braked so that the turning drive force is not transmitted downstream of the transmission, thereby maintaining the straightness of the vehicle. The brake 43 has nothing to do with the present invention,
A more detailed description is omitted.

The gear 42 is meshed with a gear 45 on an intermediate shaft 44 disposed below the torque detecting shaft 41. Further, a clutch shaft 46 is disposed below the intermediate shaft 44 so that the gear 45 is connected to the clutch shaft. The clutch gear 47 is meshed with a clutch gear 47 which is loosely fitted on the 46. A clutch slider 49 urged by a spring 48 to move toward the clutch gear 47 is provided on the clutch shaft 46, thereby forming a clutch 50 for turning on and off the turning drive system transmission. A transmission shaft 51 is disposed below the clutch shaft 46, and the clutch shaft 46 and the transmission shaft 51 are connected by reduction of gears by gears 52 and 53. Left and right gears 54L, 54R are further fixedly mounted on the transmission shaft 51 on one side and the other side of the gear 53.

As is clearly shown in FIG.
9L and 19R are provided with left and right large-diameter gears 55L and 55R. The transmission shaft 51 is different from the gears 55L and 55R in that the left gear 54L on the transmission shaft 51 is an intermediate shaft shown in FIGS. The left gear 55R on the transmission shaft 51 meshes directly with the right gear 55R via the intermediate gear 57 on the intermediate gear 57 on the transmission shaft 51, so that the left and right gears 55L, 55R are mutually engaged. They are connected so as to provide reverse rotation at a constant speed. Internal teeth 55a are formed on the inner peripheral surfaces of the boss portions of the left and right gears 55L and 55R, respectively, and the internal teeth 55a mesh with the small-diameter tooth portions formed on the left and right sun gears 21L and 21R. It is. That is, the turning driving force is applied to the left and right planetary gear mechanisms 2.
That is, the right and left sun gears 21L and 21R in 0L and 20R are input at opposite speeds at the same speed.

As shown in FIGS.
A support shaft 60 that is supported by the left and right carriers 19L and 19R via a bearing 59 is provided between the left and right carriers L and 19R. The central portion of the support shaft 60 is supported via a bearing 63 on a support member 62 fixed to the inner surface of the transmission case 1 with bolts 61. Left and right sun gear 21
Left and right gears 55 for inputting turning drive force to L and 21R
L and 55R are supported by the support shaft 60 via bearings 64 on the left and right sides of the support member 62. Reference numeral 65 denotes each planetary gear 23L, 23R supported by each carrier 19L, 19R.
It is a support shaft for supporting the R freely.

As shown in FIGS. 7 and 8, the gear type transmission 26 in the traveling drive system transmission S is provided with a rotatable operation shaft 67 extending over the inside and outside of the transmission case 1 and at the outer end of the operation shaft 67. Attaching the shift lever 68,
Transmission arm 69 fixed to operation shaft 67 in transmission case 1
The operation pin 69a at the end of the transmission arm 69 is engaged with a shift fork 71 slidably supported on a fork shaft 70 fixedly supported on the transmission case 1,
The shift fork 71 is engaged with the clutch slider 40, and the clutch slider 40 is slidably displaced on the transmission shaft 25 by the rotation of the transmission lever 68, so that the neutral position N and the high-speed gear are moved with respect to the transmission shaft 25. High speed position H to join
And a low-speed position L at which the low-speed gear 39 is coupled to the speed-change shaft 25.

As shown in FIGS. 7 and 9, the clutch 50 in the turning drive system transmission T rotatably supports the operating shaft 74 on the transmission case 1 and the supporting hardware 73 attached to the case 1 by bolts 72. At the same time, the shift fork 75 engaged with the clutch slider 49
Is fixed to a fork shaft 76 slidably supported by the transmission case 1, and a clutch arm 77 fixed to the operation shaft 74 is engaged with the shift fork 75 from the opposite side of the spring 48. According to the position of the clutch arm 77, the shift fork 75 holds the clutch slider 49 at the disengaged position of the clutch 50 at the position shown by the solid line in FIG. Clutch slider 4 with 48 forces
9 is configured to be moved to the engagement position of the clutch 50.

As shown in FIGS. 7 and 8, a cam fitting 78 is fixed to a cylindrical portion 78a fixed to an operation shaft 74, and an arm 79 is fixed to an operation shaft 67 for speed change. The spring 48 applies the cam surface of the cam metal 78 to the roller 79 a pivotally supported at the tip of the 79, via the shift fork 75, the fork shaft 76, the clutch arm 77 and the operating shaft 74. It is engaged by force. The cam fitting 78 has a cam surface 78b which engages with the roller 79a at the end of the arm 79 in a posture of the arm 79 corresponding to the neutral position N of the gear type transmission 26 shown in FIG. Gear type transmission 26
Arm 9 corresponding to the high-speed position H of
The cam surface 78c which engages with the roller 79a at the 9 end, and the roller 79a at the end of the arm 79 in the posture of the arm 79 corresponding to the low speed position L of the gear type transmission 26 shown in FIG.
Are provided, respectively.
8, 10, and 1 by the urging force of the spring 48.
As shown in FIGS. 10 and 11, the cam surfaces 78c and 78d of the cam hardware 78 which are rotationally urged in the direction of arrow P when the two cam surfaces 78c and 78d engage with the roller 79a. The cam metal 78 is set to rotate by an equal amount in the direction of arrow P from the state where the surface 78b is engaged with the roller 79a. In the state where the cam surfaces 78c and 78d are engaged with the rollers 79a, the clutch 50 is engaged by the urging force of the spring 48 while bringing the clutch arm 77 to a position shown by a chain line in FIG.

As shown in FIGS. 7 and 12-14, the shift fork 71 is selectively brought into the neutral position in one of the annular concave grooves 70N, 70H, 70L formed in the fork shaft 70 by the urging force of the spring 80. N, high-speed position H, low-speed position L
12 to 14 are provided with a detent means provided with a ball 81 for restraining the cam hardware 78 together with the detent means. The neutral position N of the shift fork 71 shown in FIG.
In the neutral position N, the cam hardware 78 is engaged with the roller 79a by the cam surface 78b, and the clutch 50 is held at the disengagement position. At the high-speed position H of the shift fork 71 and the gear type transmission 26 shown in FIG. 13, the cam hardware 78 engages the roller 79a with the cam surface 78c, and the shift fork 71 and the gear type transmission 26 shown in FIG. In the low-speed position L, the cam hardware 78 has the cam surface 78d and the rollers 79.
a, the clutch 50 is engaged by the force of the spring 48.

As shown in FIGS. 1 and 5, the charge pump 83 and the working machine pump 8 are driven simultaneously with the hydraulic pump 8.
3 are installed on each outer surface of the drive case 5 and the transmission case 1. As shown in FIG. 4, a wheel body 85 for mounting the crawler drive wheels 18L, 18R is fixedly installed on the ends of the axles 17L, 17R.

The illustrated transmission is constructed as described above, and includes a hydraulic pump 6 constituting a hydraulic transmission.
And the hydraulic motor 7 controls the traveling drive system transmission S to apply the traveling system driving force to the left and right planetary gear mechanisms 20L, 20R while controlling the inclination angle of the pump swash plate of the hydraulic pump 6 including the reverse rotation direction by a shift lever (not shown). And the left and right axles 17L, 17R are rotated in the same direction to drive the vehicle. By providing the forward / reverse switching device in the traveling transmission instead of using the hydraulic transmission, it is possible to obtain the required forward / backward travel of the vehicle.
In order to turn the vehicle, the tilt angle of the pump swash plate of the hydraulic pump 8 is adjusted by a steering operation tool (not shown) by a hydraulic pump 8 and a hydraulic motor 9 constituting a hydraulic power transmission device to one side of a neutral position or a neutral position according to the vehicle turning direction. On the other side, increase / decrease control is performed.
L and 20R are inputted with turning driving forces in opposite directions, and left and right axles 17L and 17R are rotated at equal speeds in opposite directions to obtain turning of the vehicle.

The turning driving force is transmitted to the left and right planetary gear mechanisms 20.
Since the input is made to the left and right sun gears 21L and 21R in the left and right internal gears 22R and 20R, a large reduction in the turning drive force is obtained.
The axle load at the time of turning of the vehicle is increased as compared with when the vehicle is traveling straight only by inputting the driving force to the L and 22R,
A smooth turning of the vehicle is achieved.

The gear type transmission 26 of the traveling drive system and the clutch 50 of the turning drive system are connected so that the clutch 50 is disengaged when the gear type transmission 26 is in the neutral position. Even when the operator unexpectedly touches the steering operation tool while the vehicle is stopped with the transmission 26 in the neutral position, the transmission of the turning drive force is cut off by the clutch 50 and the vehicle in the stopped state Does not turn unexpectedly. The gear type transmission is 3
In the case where the gear has more gears, the number of cam surfaces corresponding to the cam surfaces 78c and 78d may be increased correspondingly. Although the clutch 50 is shown to be engaged by the spring 48, the clutch may be disengaged by a spring.

[Brief description of the drawings]

FIG. 1 is a mechanism diagram showing a combine transmission embodying the present invention.

FIG. 2 is a schematic side view showing an arrangement of a shaft and a gear in the combine.

FIG. 3 is a vertical sectional front view showing an upper half of a traveling system transmission.

FIG. 4 is a vertical sectional front view showing a lower half of the traveling system transmission.

FIG. 5 is a vertical sectional front view showing an upper half of the turning system transmission.

FIG. 6 is a vertical sectional front view showing a lower half of the turning system transmission.

FIG. 7 is a longitudinal sectional side view showing an operation mechanism of a gear type transmission and a clutch.

FIG. 8 is a vertical sectional front view of the operation mechanism.

FIG. 9 is a longitudinal sectional front view along another longitudinal section of the operating mechanism.

FIG. 10 is a longitudinal sectional front view similar to FIG. 8, showing another state.

FIG. 11 is a longitudinal sectional front view similar to FIG. 8, showing another state.

FIG. 12 is a longitudinal sectional front view along another longitudinal section of the operation mechanism.

FIG. 13 is a longitudinal sectional front view similar to FIG. 12, showing another state.

FIG. 14 is a longitudinal sectional front view similar to FIG. 12, showing another state.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Transmission case 6 Hydraulic pump 7 Hydraulic motor 8 Hydraulic pump 9 Hydraulic motor 17L, 17R Axle 20L, 20R Planetary gear mechanism 26 Gear type transmission 40 Clutch slider 49 Clutch slider 50 Clutch 67 Operating shaft 68 Shift lever 69 Shift arm 70 Fork shaft 71 shift fork 74 operating shaft 75 shift fork 76 fork shaft 77 clutch arm 78 cam hardware 78b, 78c, 78d cam surface 79 arm 79a roller S traveling transmission T rotating transmission

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) B62D 11/08 B62D 11/08 V F16H 63/18 F16H 63/18 F-term (Reference) 3D039 AA03 AB22 3D041 AA74 AB04 AC11 AC16 AC18 AC22 AD18 AD32 AE26 AE32 3D052 AA02 AA11 DD04 EE01 FF02 GG04 HH01 JJ03 JJ12 JJ21 3J056 AA02 BA06 BB02 BB45 BE07 CC34 DA07 DA25 3J067 AC05 BA16 BB07 BB14 EA04 FB16 FB04 FB04

Claims (1)

[Claims] 1. A drive system for driving left and right axles (17L, 17R) in the same direction, and a turning drive system for driving left and right axles to generate a relative rotation difference between the left and right axles, The traveling drive system is provided with a gear type transmission (26) having a neutral position, while the turning drive system is provided with a clutch (50).
Wherein the clutch (50) is configured to be switched between an operating state and a non-operating state by a spring (48);
An operating member (7) for operating the clutch against the spring
4, 75, 77) and a movable member (79) interlocked with the operation of the operating member and the gear-type transmission (26).
Are engaged via cam means (78, 79a) which are engaged by the above-mentioned spring and are in a neutral position of the gear type transmission so as to deactivate the clutch. Power transmission control device.