JPS6227463Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention allows the vehicle to travel along a tobacco cultivation ridge or a tea cultivation ridge while straddling the ridge.
This invention relates to a hydraulic system for driving agricultural vehicles that perform various types of elevated agricultural work such as sowing, planting seedlings, and harvesting.

According to the present invention, the hydraulic motors for driving the left and right wheels of the front and rear running wheels installed in parallel on the left and right rows of the aircraft are connected to a pair of tandem type hydraulic pumps for the left and right wheels, and the swash plate angle of these hydraulic pumps is The swash plate angle of the hydraulic pump can be easily adjusted by providing adjustment plates on each adjustment shaft, connecting each adjustment plate with a plate, and connecting one of the adjustment plates to a single speed change lever with a rod. It can be carried out synchronously by one lever operation, and provides accurate and good gear shifting,
The object of the present invention is to provide a hydraulic system for running an agricultural vehicle that improves its running performance.

Hereinafter, one embodiment of the present invention will be described in detail based on the drawings. Figure 1 is an overall right side view of the elevated agricultural vehicle.
Fig. 2 is a left side view of the same, Fig. 3 is a front view of the whole, Fig. 4 is a rear view of the whole, and Fig. 5 is a plan view of the whole. 3
Reference numeral 4 denotes a body body frame that fixes the rear end side to the rear body frame 2; 4 denotes a rotation fulcrum pin that swingably connects the front end side of the body frame 3 to the front body frame 1; 5, 5; is a front axle frame that is slidably attached to and detachable from both ends of the front body frame 1 via U bolts 6, 6; 7, 7 is a front axle frame 5;
5, the front axle case is supported for horizontal rotation;
Reference numerals 8 and 8 denote front wheels that are front running wheels mounted on the lower ends of the front axle cases 7 and 7, and 9a and 9b represent left and right front wheels that are attached to the upper ends of the front axle cases 7 and 7 via reduction gear cases 10 and 10. Drive hydraulic motor 1
1 and 11 are bolts 1 on both ends of the rear body frame 2.
2, 12... and a rear axle case that is slidably attached and detached via fixed mounting plates 13, 13; 14, 14 is a rear wheel that is a rear running wheel that is mounted on the lower end of the rear axle case 11, 11; 15a; 15b is a reduction gear case 10,1 attached to the upper end of the rear axle case 11,11.
Hydraulic motors for driving the left and right rear wheels are attached through 0, 16 are the front and rear wheels 8 of the left body body frame 3,
14 is an engine section with an engine 17 mounted approximately in the center; 18 is a front and rear wheel 8 of the right side body frame 3;
14 a driving operation section to which a driving frame 19 is fixed approximately in the center and equipped with a driver's seat 20 and a handle 21; 22 a hydraulic oil tank installed below the driver's seat 20; 23 a front center of the body frame 3; The left row and right row hydraulic motors 9a, 15 mounted on the
a. A hydraulic pump unit incorporating two tandem hydraulic pumps 24a and 24b for operating 9b and 15b, 25 is drivingly connected to the engine 17, and one output shaft is connected to the input shaft of the hydraulic pump unit 23. A PTO transmission case 26 is the other PTO output shaft 2 of the transmission case 25.
7 is a PTO housing for removably and directionally connecting the PTO to the rear; 28 is a gear shift lever that is connected to the hydraulic pump unit 23 to perform a traveling gear shift operation; 29 is a PTO gear lever provided in the PTO transmission case 25; 30 32 is a rotary cultivating machine equipped with a hydraulic elevator having a lift arm 31 provided approximately at the center of the rear body frame 2, and a rotary 35 towed the machine rearward via a lower link 33 and a top link 34. Alternatively, the machine is configured to travel over tea cultivation ridges and the like, and to perform tillage work using the working machine 32.

FIG. 6 is a hydraulic circuit diagram in which the hydraulic pump unit 23 is connected to the hydraulic oil tank 22, and the discharge side of one swash plate adjustable variable displacement hydraulic pump 24a of the pump unit 23 is placed on the left side of the machine. Hydraulic motors 9a, 15 for running wheels 8, 14 to be provided
a to the parallel circuit, and these hydraulic motors 9a,
A two-position manual switching valve 36 for switching between 2-wheel drive and 4-wheel drive is interposed between 15b and 15b to appropriately cut off the hydraulic pressure supply to the hydraulic motor 9a. In addition, the discharge side of the other variable displacement hydraulic pump 24b is connected to the hydraulic motors 9b and 15b of the running wheels 8 and 14 disposed on the right row of the machine body in a parallel circuit, and the hydraulic motor 9b is connected between the hydraulic motors 9b and 15b. The other 2-position manual switching valve 37 for switching between 2WD and 4WD, which appropriately cuts off the hydraulic pressure supply.
are intervening.

Further, between the hydraulic motor 15a and the switching valve 36 and the hydraulic motor 15b and the switching valve 37, the left and right running wheels 8, 14.
Alternatively, a 3-position manual switching valve 38 is provided for switching to a differential suspension (defroc) or emergency drive suspension (emergency) state.

Furthermore, shuttle valves 39 and 40 are provided between the switching valves 36 and 37 and the hydraulic motors 9a and 9b.
These shuttle valves 39, 4
A two-position manual switching valve 41 for oil replenishment is interposed in the connection circuit between the outlet side of the hydraulic oil tank 22 and the hydraulic oil tank 22.

On the other hand, by operating the handle 21, the front wheels 8,
A steering cylinder 42 for performing directional control of 8 is connected to the hydraulic oil tank 22 via a power steering 43. Note that 45 indicates the hydraulic pumps 24a, 24b and the hydraulic oil tank 22.
45 is an oil cooler; 46 is a single 2WD/4WD switching operation lever for operating the switching valves 36, 37, and 41 in conjunction with each other; 47 is the switching valve 38; Differential (differential)
An operating lever 48 is an accelerator lever for switching between differential suspension (defroc) and emergency drive suspension (emergency).

By the way, as shown in FIGS. 7 to 14, the base end of the gear shift lever 28 is connected to a pivot shaft 51 which is fixed to the body frame 3 via a bolt 49 and a locking plate 50, and a spherical joint 52 is supported by the lever. 28 A shift guide groove 57 of a lever guide plate 56 whose tip portion is formed to be swingable left and right and is fixed to the frame 3 via bolts 53, 54 and a connecting plate 55.
The lever 28 is configured to engage and support an intermediate portion of the lever 28. The contact portion of the lever 28 with the guide plate 56 is formed into a flat engagement portion 58 having a substantially elliptical cross section, and one side thereof is connected to the gear change notch 5 of the guide groove 57.
9, and the position of the lever 28 is maintained by the spring force of a spring 61 interposed between the lever 28 and a receiving plate 60 attached to the pivot shaft 51.

Further, a pin 6 is provided near the base end of the speed change lever 28.
2, and the other end of the rod 63 is connected to a swash plate angle adjusting shaft 64 for controlling the discharge amount of one of the hydraulic pumps 24b of the hydraulic pump unit 23. An adjusting plate 65 and a shaft 66 are connected to each other through a connecting rod 63. It is connected through. Furthermore, these hydraulic pumps 2
A fine adjustment section 69 for synchronizing the swash plate angles of 4a and 24b is provided, and an L-shaped plate 70 attached to the shaft 66 and an L-shaped plate 72 attached to the tip of the adjustment plate 68 via a shaft 71 are connected by adjusting bolts. 73, the swash plate angles of these tandem hydraulic pumps 24a, 24b are synchronized by adjusting the bolt 73, and the swash plate angle adjustment shafts 64, 67 are connected via the rod 63. By interlocking and connecting with one speed change lever 28, the discharge amount is synchronously varied.

This embodiment is constructed as described above, and when the switching valves 36, 37, 38, and 41 are currently in the state shown in FIG. 6, the switching valve 38 is in the neutral position and the left column hydraulic motor 9a , 15a and the hydraulic motors 9b, 15b on the right row are in a so-called differential suspension (deflock) state where the connection circuit is cut off, and the hydraulic oil tank 22 is connected via the hydraulic pumps 24a, 24b.
The hydraulic pressure from the left and right row hydraulic motors 9a, 15
a, 9b, and 15b, and the pump 24a drives the motors 9a, 15a, and the pump 24b drives the motors 9b, 15b appropriately in the forward and reverse directions.

Then, by operating the lever 47, the switching valve 47
When switched in the direction of the solid line arrow, the left row hydraulic motors 9a, 15a and the right row hydraulic motors 9b, 15b
The hydraulic pressure supply circuits are connected to create a so-called differential state. And now the hydraulic motors 24a, 24
b, or when an abnormality occurs in this hydraulic drive system, when the switching valve 38 is switched in the direction of the dashed arrow by operating the lever 47, the left row hydraulic motors 9a, 15
The hydraulic outlet of the hydraulic motors 9a, 15a and the hydraulic inlets of the hydraulic motors 9b and 15b in the right row communicate with each other, respectively, and the hydraulic outlets of the hydraulic motors 9b and 15b communicate with the hydraulic inlets of the hydraulic motors 9a and 15a, respectively.
A closed circuit is formed between the motors 9a, 9b, 15a, and 15b with no-load rotation due to oil pressure circulation. As a result, the hydraulic circuit system in which the abnormality has occurred can be easily moved with respect to the aircraft body by external force or the like without causing a hydraulic brake state.

In addition, in this 4WD state where the front and rear wheels 8, 8, 9, and 9 are driven, when the operation lever 46 is operated to switch the switching valves 36, 37, and 41, the hydraulic motors 9a, The supply of hydraulic pressure to the hydraulic motor 9b is cut off, the left and right front wheels 8, 8 stop driving, and only the rear wheels 14, 14 are driven, resulting in a two-wheel drive state. During this state, the hydraulic motors 9a,
9b is in a state where oil from the hydraulic oil tank 22 is replenished and circulated through the switching valve 41 and the drain circuit 41a.

On the other hand, while driving, the swash plate angles of the hydraulic pumps 24a, 24b are synchronously displaced by variable interlocking operation of the adjustment shafts 64, 67 via the speed change lever 28, causing rotation of the front and rear wheels 8, 8, 14, 14. The speed is changed, and this synchronization adjustment is performed using the bolt 73 of the fine adjustment section 69. Also,
The operation lever 28 is provided with a notch 5 of a guide plate 56.
Since the lever 28 is formed with a flat engaging portion 58 that engages with the lever 9, the lever 28 can be reliably maintained at its shift position.

11 to 14 show another modified structure of the gear shift lever 28, in which a cylindrical shaft 75 is supported on the pivot shaft 51 via a spherical joint 74, and a compression spring 76 is supported on the cylindrical shaft 75. A notch engagement release flat part 77 whose flat direction is different from that of the engagement part 58 by approximately 90 degrees is formed above the notch engagement flat engagement part 58 provided on the lever 28a. Then, the gear shift lever 2
When 8a is rotated 90 degrees or pushed downward against the spring 76, the engaging portion 58 or the flat portion 7
7 from the notch 59 and its flat surface 58a,
The lever 28a is configured to be returned to the neutral position with the lever 77a aligned along the surface of the guide groove 57. In the case of this configuration, since the neutral position can be returned with one operation, the operation is easy and reliable, and has the advantage of being extremely safe. This configuration also has the same functions and effects as those of the above-mentioned embodiment, so the same components are given the same numbers and detailed explanation thereof will be omitted.

As is clear from the above embodiments, the present invention is based on the front and rear running wheels 8 and 1 installed in parallel on the left and right rows of the fuselage.
4.8, 14 left and right wheel drive hydraulic motors 9a, 1
5a, 9b, 15b are connected to a pair of tandem type left and right wheel hydraulic pumps 24a, 24b, and the swash plate angle adjustment shaft 6 of these hydraulic pumps 24a, 24b is
Adjustment plates 65 and 68 are provided at 4 and 67, respectively, and the adjustment plates 65 and 68 are connected by plates 70 and 72, and one adjustment plate 65 is connected to the single speed change lever 28 by a rod 63. Therefore, the swash plate angles of the hydraulic pumps 24a and 24b can be synchronously adjusted by operating a single lever 28,
This has the advantage that accurate and good speed change running can be performed, and that the running performance can therefore be improved.

[Brief explanation of the drawing]

Figure 1 is an overall right side view of the elevated agricultural vehicle, Figure 2
The figure is a left side view of the same, Figure 3 is a front view of the same, Figure 4 is a rear view of the same, Figure 5 is a plan view of the whole, and Figure 6 is a front view of the same.
7 is a side view of the main parts, FIG. 8 is a plan view of the main parts, FIG. 9 is an enlarged view of the gear shift lever, and FIG. 10 is an enlarged view of the same plane. 11 and 12 are explanatory diagrams showing other examples of deformed structures, FIG. 13 is a sectional view taken along the - line of the previous figure, and FIG.
The figure is a sectional view taken along the - line of the previous figure. 8, 14... Running wheels, 9a, 9b, 15a, 1
5b...Hydraulic motor, 24a, 24b...Hydraulic pump, 28...Speed lever, 64, 67...Swash plate angle adjustment shaft.

Claims (1)

[Scope of claim for utility model registration] Hydraulic motors 9a, 9 for driving the left and right wheels of the front and rear running wheels 8, 14 installed in parallel on the left and right rows of the fuselage
b, 15a, 15b are connected to a pair of tandem type left and right wheel hydraulic pumps 24a, 24b, and adjustment plates 65, 68 are provided on the swash plate angle adjustment shafts 64, 67 of these hydraulic pumps 24a, 24b, respectively. A hydraulic system for running an agricultural vehicle, characterized in that plates 65 and 68 are connected by plates 70 and 72, and one adjustment plate 65 is connected to a single gear shift lever 28 by a rod 63. Swash plate angle adjustment shaft 6 of hydraulic pumps 24a, 24b
4, 67 are provided with a fine adjustment section 69 for adjusting the angle of the swash plate.A hydraulic system for running an agricultural vehicle according to claim 1, which is registered as a utility model.