JPH0790803B2 - Suspension device for tracked vehicle - Google Patents

Description

The present invention relates to a suspension system for a track-tracked vehicle.

[Conventional technology]

FIGS. 2 to 4 show only one side of the hydraulic / pneumatic suspension system including the hydraulic cylinder, accumulator and the like of the tracked vehicle. In FIG. 2, 1 is a rolling wheel, 2 is a rolling wheel arm that supports the rolling wheel 1, 100 is a crawler belt suspended on the rolling wheel 1, and in FIG. 3, 2 is a rolling wheel arm and 3 is a rolling wheel arm. Piston arm integrated with the wheel arm 2, 4 is a connecting rod attached to the piston arm, 5
Is a piston attached to the connecting rod 4, 6 is a cylinder in which the piston 5 is slidably fitted, 7 is a valve block provided at the top of the cylinder, and 8 is connected to the cylinder 6 via the valve block 7. Accumulator, 9 is a wheel case upper plate, 10 is a wheel case. Further, in FIG. 4, reference numeral 11 denotes a wheel case mounting flange, on which the hydraulic / pneumatic suspension device is mounted on the vehicle body 12. Further, FIG. 5 shows the details of the hydraulic circuit including the valve block 7 of the conventional tracked vehicle, including accumulator side port 13, safety valve port 14, cylinder side port 15, relief valve 16, check valve 17, safety valve 18, A throttle 19 is provided on the valve block 7. A pilot check valve 20 is provided in the upper plate 9 of the wheel case. P1 is an oil passage to a hydraulic power source, and is connected to an engine-driven hydraulic pump 22 via a switching valve 21. 23 is a relief valve and 24 is a drain tank. P2 is an oil passage from the pilot hydraulic pressure source, and P3 is an oil passage connecting the safety valve port 14, the relief valve 23 and the drain tank 24.

As for the operation, when the rolling wheel 1 moves up and down according to the unevenness of the road surface, the displacement is transmitted as the displacement of the piston 5 via the piston arm 3 and the connecting rod 4 which have the same swing center as the rolling wheel arm 2. At this time, if the pilot check valve 20 is closed, the cylinder 6 and the accumulator 8 become a closed circuit,
The movement of the piston 5 is transmitted to the accumulator 8 via the hydraulic oil, and the rolling wheel 1 is elastically supported by the accumulator 8. That is, it acts as a buffer. Further, vibrations associated with traveling are damped in the valve block 7. In other words, the traveling vibration is damped by the resistance of the hydraulic oil passing through the check valve 17 and the throttle 19 due to the pressure difference acting between the ports 13 and 15 in the valve block 7. However, if the pressure difference becomes larger than the set value of the relief valve 16, the relief valve
Since the 16 opens, the damping force does not increase any further. Further, the check valve 17 is provided so that the damping is not so effective when the piston is raised. The setting value of the relief valve 16 and the presence / absence of the check valve 17 are optimally set depending on the riding comfort. Next, regarding the body attitude control, open the pilot check valve 20 from P2 by the operating oil pressure from the pilot oil pressure source, and open P1
If high-pressure oil is supplied from the pump 22, the amount of hydraulic oil increases, and the roller 1 extends. Further, when the pilot check valve 20 is opened after switching the direction switching valve 21, the hydraulic oil returns to the drain tank due to the pressure due to the weight of the vehicle body, whereby the rolling wheels 1 contract and the vehicle body posture can be changed.

[Problems to be solved by the invention]

In the case of a conventional tracked vehicle with a suspension system, in the case of fine irregularities on the ground, it is better to make the accumulator 8 that elastically supports the rolling wheels 1 relatively large, that is, to make the spring constant small and to use the throttle 19 less often. Vibration is reduced. On the other hand, in the case of large irregularities on the ground, if the spring constant is large and the throttle 19 is not used to some extent, bottoming occurs in which the rolling wheel 1 contracts the entire stroke, and furthermore, after the irregularities have passed, the vehicle body continues to sway.
In this way, it was difficult to match the design constants of the suspension system with various road surface irregularities.

[Means for solving problems]

For this reason, the suspension system of the track-tracked vehicle according to the present invention has
The input shaft is connected to the variable discharge hydraulic pump and the sun gear of the planetary gear train, the hydraulic motor rotated by the discharge oil of the hydraulic pump is connected to the ring gear of the planetary gear train, and the output shaft is the planetary gear of the planetary gear train. In a tracked vehicle having a suspension system composed of a hydraulic mechanical transmission connected to gears, a hydraulic cylinder, and an accumulator connected to the clutch, a clutch capable of fixing rotation of a hydraulic motor, an oil passage between the hydraulic pump and the hydraulic motor, and the hydraulic pressure. It is characterized in that it is provided between the cylinders, and means for guiding the hydraulic pump discharge oil to the hydraulic cylinder by the switching means or for guiding the hydraulic oil in the hydraulic cylinder to the drain tank is provided.

(Operation) According to the above-described suspension system for a tracked vehicle of the present invention, the hydraulic oil of the suspension system is drained from the pushed up rolling wheel, and the high pressure oil is supplied to the rolling wheel in the recess, so that the vehicle body is Vibration does not occur. For this purpose, there is a high-capacity high-pressure pump, but in the device of the present invention, no special pump is required because the high-pressure oil of the transmission hydraulic pump is introduced.

〔Example〕

A suspension system for a track-mounted vehicle as an embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows an embodiment of the device of the present invention. The suspension device shown in the upper right part of the figure is the same as that shown in FIGS. Compared with FIG. 5 showing a conventional hydraulic circuit, a new point is that a hydraulic circuit including a hydraulic mechanical transmission device shown in the lower left portion of FIG. 1 is added. Reference numeral 26 is an input shaft connected to the engine, and 261 is a gear that drives a pump described later and is fixed to the input shaft 26. A sun gear 262 is a planetary gear train and is fixed to the input shaft 26. 27
Is connected to a rear transmission (not shown) by an output shaft. 271 is a planetary gear of a planetary gear train, and a plurality of planetary gears are mounted with the output shaft 27 as a carrier and mesh with the sun gear 262. 28 is a ring gear of a planetary gear system, which is driven by a motor described later and meshes with the planetary gear 271. 29 is a variable discharge hydraulic pump, 291 is a gear fixed to the drive shaft of the hydraulic pump 29, and meshes with the gear 261. A hydraulic motor 30 is normally rotated by high-pressure oil from the hydraulic pump 29. 301 is a gear fixed to the shaft of the hydraulic motor 30 and meshes with the ring gear 28. 302 is a clutch which is attached to the shaft of the hydraulic motor 30 to restrict the rotation of the shaft of the hydraulic motor 30. 31,3
Reference numeral 2 is a three-position three-way valve that connects the oil passage connecting the hydraulic pump 29 and the hydraulic motor 30 to the cylinder 6 of the suspension device, and switches the cylinder 6 and the drain tank.

Explaining the operation, the power from the engine (not shown) reaches the output shaft 27 from the manpower shaft 26 via the gears 262, 271 and at the same time reaches the hydraulic pump 29 via the gears 261 and 291, and becomes hydraulic power to the hydraulic motor 30. Further, the gear 301,
Output shaft 27 is reached via 28 and 271. Hydraulic pump at this time
When the discharge amount of 29 is changed, the rotation speed of the hydraulic motor 30, that is, the gear 301 or 28
The rotation speed of can be changed. As a result, the input shaft 26
The number of rotations of the output shaft 27 can be varied with respect to the number of rotations. Therefore, if the number of revolutions (discharging amount) of the hydraulic pump 29 can be changed steplessly, the output shaft 26
The rotation speed of 27 can be changed steplessly. That is, the gears 261, 291, the hydraulic pump 29, the hydraulic motor 30, and the gears 301, 28 constitute a continuously variable transmission, and can transmit the maximum driving force at each vehicle speed. In addition, 33 and 34 are check valves connected to a hydraulic power source (not shown), and are for replenishing the hydraulic oil discharged from the hydraulic circuit. Since the suspension system of the tracked vehicle of this embodiment is constructed as described above, the clutch 302 fixes the hydraulic motor 30 so that it does not rotate when it is necessary to travel on rough terrain at high speed. Then, the hydraulic pressure generated by the pump 29 is guided to the cylinder 6 by the three-position three-way valve 31 or 32.
At this time, regarding the unevenness of the ground, if the three-position three-way valves 31, 32 are operated so as to supply the hydraulic oil of the suspension device when the rolling wheel should extend and to remove it when it should contract, high-pressure oil will be generated in the rolling wheel that has entered the recess. The hydraulic oil in the cylinder 6 is drained by the rolling wheels that are supplied to the cylinder 6 and pushed up, so that the vehicle body does not vibrate. In addition, as a large capacity high pressure pump for this purpose,
Since the hydraulic pump used for conventional shifting is used as it is, no special pump is required, which is advantageous in terms of space and cost. As a control method, when the rolling wheel extends into the recess, the rolling wheel expands, and the hydraulic pressure in the cylinder decreases, while in the convex, the hydraulic pressure rises. Therefore, the hydraulic pressure is measured. Should be controlled. When such control is carried out, the motor 30 is fixed by the clutch 302 so as not to rotate, so that the function of the continuously variable transmission is lost and the gear train becomes a simple gear train, so that the maximum driving force can be transmitted at each vehicle speed. However, it is sufficient for the purpose of, for example, reducing vibration and vibration for a short time when the occupant does some work.

[Advantages of the Invention] As described in detail above, according to the suspension device for a tracked vehicle of the present invention, in a hydraulic suspension system for a tracked vehicle having a hydraulic mechanical transmission device, a transmission device hydraulic pump The high-pressure oil is guided to the hydraulic suspension system through an appropriate switching valve, and with respect to the unevenness of the ground, the high-pressure oil is supplied when the rolling wheels should extend and the hydraulic oil of the suspension system is drained when the rolling wheels should contract. With the simple structure shown in the range, the spring constant of the suspension system can be changed according to the unevenness of various road surfaces, vibration and shaking of the tracked vehicle can be reduced, and riding comfort can be improved in a small space and at low cost. it can.

[Brief description of drawings]

FIG. 1 is a system diagram of a hydraulic circuit and a hydraulic mechanical transmission device showing an embodiment of a suspension system for a tracked vehicle of the present invention. Second
FIGS. 4 to 4 are views showing a hydraulic suspension system of a tracked vehicle, and FIG. 2 is a perspective view showing one side of the hydraulic suspension system, and FIG.
FIG. 4 is a sectional view showing a main part of the suspension device, and FIG. 4 is a front view of the main part of the suspension device. FIG. 5 is a hydraulic circuit diagram applied to a conventional tracked vehicle. 1 …… Roller, 2 …… Roller arm, 3 …… Piston arm, 4…
… Connecting rod, 5 …… Piston, 6 …… Cylinder, 7 …… Valve block, 8 …… Accumulator, 9 …… Rolling case upper plate, 10
…… Roller case, 11 …… Flange, 12 …… Car body, 13 …… Accumulator side port, 14 …… Safety valve port, 15 …… Cylinder side port, 16,18,23 …… Safety valve, 17,20,33 , 34 …… Check valve, 19 …… Throttle, 21 …… Switching valve, 24 …… Drain tank, 26
...... Input shaft, 27 …… Output shaft, 28 …… Ring gear, 29 …… Hydraulic pump, 30 …… Hydraulic motor, 31,32 …… 3-position 3-way valve, 26
1,291,301 …… Gear, 262 …… Sun gear, 271 …… Planet gear,
302 …… Clutch

Claims (1)

[Claims] 1. A travel system, wherein an input shaft is connected to a variable discharge hydraulic pump and a sun gear of a planetary gear train, and a hydraulic motor rotated by the discharge oil of the hydraulic pump is connected to a ring gear of the planetary gear train, In a tracked vehicle having a suspension system including a hydraulic mechanical transmission device having an output shaft connected to a planetary gear of the planetary gear train, a hydraulic cylinder, and an accumulator connected to the clutch, a clutch capable of fixing rotation of a hydraulic motor, a hydraulic pump, and A means provided between the hydraulic passage between the hydraulic motors and the hydraulic cylinder for guiding the hydraulic pump discharge oil to the hydraulic cylinder by the switching means or the hydraulic oil in the hydraulic cylinder to the drain tank is provided. Suspension system for tracked vehicles.