JPH0730179U - Control device for hydraulically driven vehicle - Google Patents

Abstract

(57) [Abstract] [Purpose] In a hydraulic traveling vehicle that can change the traveling direction and speed of the left and right traveling devices separately with a hydraulic transmission,
Make sure that the speed difference between the left and right traveling devices does not become too large so that you can operate safely. [Structure] The left and right traveling devices 13 and 13 are stopped, respectively, in response to the forward and backward rotation of the left and right steering speed change levers 7 and 7 from the front-rear intermediate position, and the forward and backward speed increases. Steering gearshift levers 7, 7 and hydraulic transmissions 25, 2
5 are interlocked by interlocking mechanisms 11 and 11, and both interlocking mechanisms 11 and 1
The interlocking portion 85 that interlocks to rotate the other steering gearshift lever 7 in the same direction as the one steering gearshift lever 7 rotates.
Is provided with a certain amount of play.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a hydraulic traveling vehicle in which the left and right traveling devices including wheels and crawlers are driven by hydraulic transmissions provided on the left and right, respectively, and the traveling direction and traveling speed of the left and right traveling devices are changed separately. Control device.

[0002]

[Prior art]

 The hydraulic traveling vehicle is provided with a hydraulic transmission (HST) including a hydraulic pump and a hydraulic motor on the drive sides of the left and right traveling devices, respectively, and steering steering shift levers for operating the shifting of the left and right hydraulic transmissions. ing. Various turning methods can be selected by operating the left and right steering speed change levers to change the running direction and speed of the left and right running devices. For example, the turning radius can be changed by changing the traveling speed of the left and right traveling devices, turning on the spot by stopping the traveling device on one side and driving one side, and spinning by rotating in the opposite direction to the left and right. You can turn. Since various turning methods can be selected in this way, it is used as a control device for agricultural vehicles such as tractors and transport vehicles used at construction sites.

[0003]

[Problems to be solved by the device]

 In such a control device for a hydraulically traveling vehicle, if the speed difference between the left and right traveling devices is large, the vehicle may suddenly turn and the vehicle body may become unstable, resulting in a dangerous condition for the operator.

[0004]

[Means for Solving the Problems]

 Therefore, in the present invention, in the control device for a hydraulic traveling vehicle in which the traveling directions and speeds of the left and right traveling devices 13 and 13 are changed by the steering and shifting levers 7 and 7, respectively, in the front and rear intermediate positions of the left and right steering and shifting levers 7 and 7. The steering gearshift levers 7 and 7 and the hydraulic transmission 25 allow the left and right traveling devices 13 and 13 to move from stop to forward speed increase and reverse speed increase, respectively, in response to the rotation from the position to the front and the rotation to the rear. , 25 are interlocked by interlocking mechanisms 11 and 11, and both interlocking mechanisms 11 and 11 are interlocked to rotate the other steering gearshift lever 7 in the same direction as one steering gearshift lever 7 pivots. The control unit of the hydraulic traveling vehicle is configured by providing the interlocking portion 85 with a certain amount of play.

[0005]

[Operation and effect of the device]

 The left and right steering speed change levers 7, 7 turn forward or backward in a straight line if they rotate in the same direction by the same angle, turn when the left and right turning angles are changed, and spin turn if they turn in the opposite left and right directions. However, even if only one steering lever 7 is rotated significantly, the other steering lever 7 is also rotated in the same direction depending on the play range of the interlocking portion 85, resulting in a gentle turning state. Even if the steering levers 7 and 7 are to be largely rotated in the opposite directions, the movement is restricted by the interlocking portion 85, and a gentle spin turning is performed. Even if the steering gearshift levers 7, 7 are inadvertently operated in this way, the vehicle body does not make a sudden movement and is safe.

[0006]

【Example】

 Next, an embodiment of the present invention will be described with reference to the drawings. A loading platform 14 is mounted on the front side of a chassis 5 equipped with a traveling device composed of crawlers 13, and a prime mover 2 is mounted on the rear side thereof. The periphery of the prime mover 2 is surrounded by a pipe-shaped prime mover frame 4, and the top and left and right sides of the prime mover frame 4 are covered with plates to form a prime mover frame 3. The driving frame 4 has its rear lower end pivotally supported by a horizontal shaft 6 provided on a chassis 5, and its left and right upper front ends are engaged with pins 17 by hooks 16 provided on the upper part of a pillar 15 standing upright from the chassis 5. Fixed. The pin 17 is disengaged from the hook 16 by rotating the lever 18, and is biased toward the engaging side by a spring.

On the upper part of the driving frame 4, a steering operation tool 9 such as steering gearshift levers 7 and 7 and a traveling clutch lever 8 arranged side by side is provided upright. A parking brake lever 19 is provided on the rear side of the drive frame 4. On the rear side of the prime mover 2, a hydraulic pump 21 for damping the loading platform 14 is attached to a support frame 20 fixed to the prime mover 2, and a prime mover 22 attached to an output shaft of the prime mover 2 and an input shaft of the pump 21. The driving force is transmitted by the belt 24 to the pulley 23 attached to the.

A hydraulic transmission (HST) 25 is attached to the left and right sides of the transmission case 10 attached to the lower part of the chassis 5, and a transmission 26 and a relay pulley 27 are attached between an input shaft of the hydraulic transmission 25 and a relay pulley 27. A belt 28 is wound around the belt 28, and a belt 29 is wound between the driving pulley 22 and the relay pulley 27 to transmit power. Numeral 30 is a clutch pulley for connecting and disconnecting the power by tensioning or loosening the belt 29, which is connected to the traveling clutch lever 8 by a wire.

As shown in FIG. 1, the steering gearshift levers 7, 7 and the gearshift lever 31 of the hydraulic transmission 25 are connected by a link mechanism 11. The steering gearshift levers 7, 7 are pivotally supported by left and right mounting cylinders 33, 33 externally fitted on a horizontal shaft 32 mounted horizontally on the driving frame 4 so as to be rotatable left and right, and are formed in the driving frame 3 in the front-back direction. The guide grooves 34, 34 are projected upward. The ends of the arms 35, 35 protruding from the left and right mounting cylinders 33, 33 are connected to the ends of the protruding arms 38, 38 of the left and right relay cylinders 37, 37 pivotally supported by a horizontal shaft 36 pivotally supported on the chassis 5 side. They are connected by rods 39, 39.

An engaging piece 40 is projected from one connecting rod 39 toward the other connecting rod 39, and the engaging piece 40 is inserted from the other connecting rod 39 with a space from above and below. The interlocking portion 85 is configured by projecting the pieces 41 and 42. 43 and 43 are adjusting nuts for adjusting the length of the connecting rod 39. The left and right steering speed change levers 7, 7 are arranged such that when one of the steering speed change levers 7 is rotated by the engaging pieces 40, 41, 42 to a certain extent or more, the other steering speed change lever 7 is also rotated in the same direction. Become.

The position of the connecting pivot shaft 12 portion with the bent protruding arm 38 at the lower end of the connecting rod 39 is such that when the steering speed change levers 7, 7 are in the neutral position, the axial direction thereof is the drive frame frame 4. The connecting link 11 of the steering gearshift levers 7 and 7 and the gearshift lever 31 of the hydraulic transmission 25 moves even when the driving frame frame 4 is rotated rearward, which coincides with the axial position of the horizontal shaft 6 which pivotally supports. Instead, the driving frame 2 can be largely rotated rearward to open the periphery of the driving machine 2.

Another arm 44, 44 is projected downward from the relay cylinder 37, 37, and the transmission lever 31 of the hydraulic transmission 25 provided on the tip ends of the arm 44, 44 and the left and right side surfaces of the transmission case 10 is connected to the rod. 45 and 45 are connected. Further, the left and right relay cylinders 37, 37 are provided with pins 46, 47 projecting parallel to the cylinder center direction so that the left and right steering speed change levers 7, 7 are not in the front-rear intermediate position and the traveling device is not driven. When the position is reached, the pins 46 and 47 are vertically aligned and the parking brake operating device 48 described later is rotatable.

The parking brake actuator 48 is rotatably supported on a pivot shaft 49 provided on the chassis 5 in a direction orthogonal to the axial direction of the relay cylinders 37, 37. A restricting plate 51 having a U-shaped groove 50 passing therethrough and an operating plate 54 for holding a shift lever 53 for shifting a parking gear 52 in the mission case 10 are provided projectingly, and a pin 55 fixed to the restricting plate 51 is provided. The parking lever 19 is connected by a wire 56. Accordingly, the parking gear 52 can be rotated to the parking position by rotating the parking lever 19 only when the left and right steering speed change levers 7, 7 are in the neutral position and the operating tool 48 is rotated. 52 can be shifted.

The internal structure of the mission case 10 is configured as shown in the transmission mechanism diagram of FIG. A small gear 58 is fixed to the input shaft 57 in the transmission case 10 connected to the left hydraulic transmission 25, and the small gear 58 is meshed with the large gear 60 fixed to the first intermediate shaft 59 to engage the first intermediate shaft. 59 is rotated to mesh the small gear 61 fixed to the first intermediate shaft 59 with the large gear 63 fixed to the second intermediate shaft 62 to rotate the second intermediate shaft 62. The left gear transmission system 86 is configured to drive the left crawler 13 by rotating the left wheel sprocket 67 by meshing the small gear 64 fixed to the wheel gear 66 of the left wheel shaft 65.

A small gear 69 is fixed to the input shaft 68 connected to the right hydraulic transmission 25, and the parking gear 52 is slid by spline fitting and fixed to the input shaft 57 of the left hydraulic transmission 25. It can be engaged with and disengaged from the stop gear 80. When the parking gear 52 meshes with the stop gear 80, the left gear transmission system and the right gear transmission system form a closed loop, and the left and right crawlers are connected in a reverse rotation relationship. The small gear 69 meshes with the large gear portion 71 of the large and small gear 70 that is rotatably fitted to the first intermediate shaft 59, and the small gear portion 72 of this large and small gear 70 is rotatably fitted to the second intermediate shaft 62. The small gear portion 75 of the small gear 73 meshes with the large gear portion 74 of the large gear 73, and the small gear portion 75 of the large gear 73 meshes with the wheel gear 77 of the right wheel shaft 76 to rotate the right wheel sprocket 78 and drive the right crawler 13 to drive the right gear. The transmission system 87 is configured.

[Brief description of drawings]

FIG. 1 is a partially enlarged perspective view.

FIG. 2 is a partially enlarged perspective view.

FIG. 3 is a partial side view.

FIG. 4 is a partial transmission mechanism diagram.

[Explanation of symbols]

 7 Steering speed change lever 13 Travel device 25 Hydraulic transmission 85 Interlocking part

Claims (1)

[Scope of utility model registration request] 1. A steering system for a hydraulic traveling vehicle in which the traveling directions and speeds of the left and right traveling devices (13) and (13) are individually changed by steering steering levers (7), (7). The left and right traveling devices (13), corresponding to the forward rotation and the backward rotation of the levers (7) and (7) from the front-rear intermediate position,
The steering speed change levers (7) and (7) and the hydraulic transmission (2) are set so that (13) changes from stop to forward speed increase and reverse speed increase.
5) and (25) are interlocked by interlocking mechanisms (11) and (11), and both interlocking mechanisms (11) and (11) are operated to rotate one steering gear shift lever (7) to the other. Shift lever (7)
A control device for a hydraulic traveling vehicle in which an interlocking portion (85) interlocking with each other so as to rotate in the same direction is provided with a certain amount of play.