JPH0414251Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field This invention relates to a hydroneumatic suspension device used for the wheels of tracked vehicles.

2. Description of the Related Art As a conventional hydroneumatic suspension device used for the wheels of a tracked vehicle, the one shown in FIG. 4 is known. The suspension device includes a suspension cylinder a, and an accumulator e having a hydraulic chamber d communicating with the hydraulic chamber b of the suspension cylinder a via a pressure reducing valve c.
Therefore, the inside of the accumulator e is divided by the free piston f into the above-mentioned hydraulic chamber d and a gas chamber g filled with nitrogen gas. The tip of a piston rod h that protrudes from the suspension cylinder a is pivotally attached to the tip of a lever k that rotates together with a swinging arm j around an axis i, and rotates to the tip of the swinging arm j. A ring l is rotatably mounted. The operation of the suspension device described above will be explained next. When the roller l receives an upward external force, the swing arm j and the lever k are rotated counterclockwise, and the hydraulic chamber b of the suspension cylinder a is rotated. The oil inside is pressurized, and this oil flows into the hydraulic chamber d of the accumulator e through the pressure reducing valve c, and the pressure is accumulated in the accumulator e. When the external force applied to the wheel l is removed, the hydraulic pressure accumulated in the hydraulic chamber d of the accumulator e is pushed back to the hydraulic chamber b of the suspension cylinder a via the pressure reducing valve c, and this causes the swing arm j and the wheel l is rotated downward and returns to its original position.

In addition, a hydraulic circuit shown in FIG. 5 is constructed inside the pressure reducing valve c, and a throttle m is drawn from the hydraulic chamber b of the suspension cylinder a to the hydraulic chamber d of the accumulator e.
When the oil moves through the aperture m, shocks and vibrations are attenuated by the aperture m. Note that n in the figure indicates a safety valve that releases abnormal pressure in the circuit on the side b of the hydraulic chamber.

Problems that the invention aims to solve However, in the conventional suspension device described above, when the safety valve n operates due to the abnormal pressure generated in the pressure reducing valve c and the hydraulic pressure in the circuit is released, the hydraulic pressure in the hydraulic chamber b is normal. Even if the circuit returns to normal, the amount of oil released from the safety valve n is lower than in the circuit, so the initial state is not restored, and the vehicle becomes tilted, making it difficult to continue driving. There were some problems such as.

This invention was made for the purpose of improving the above-mentioned problems.

Means and operation for solving the problem A suspension cylinder that is linked to a swing arm to which a roller is attached, and an accumulator that communicates with the hydraulic chamber of the suspension cylinder via a pressure reducing valve, In addition, in a suspension device in which vibrations and shocks are damped by the throttle of the pressure reducing valve when the oil in the suspension cylinder moves to the accumulator side via the pressure reducing valve, the oil on the upstream side of the throttle of the pressure reducing valve and the check valve is used. By communicating the pressure accumulation chamber of the reservoir cylinder with the oil passage of the safety valve, the abnormal pressure generated in the pressure reducing valve is accumulated and absorbed by the reservoir cylinder, and the hydraulic pressure in the reservoir cylinder is suspended when the abnormal pressure disappears. A hydroneumatic suspension device for a tracked vehicle, which allows the suspension device to operate normally even after abnormal pressure disappears by replenishing the suspension cylinder.

Embodiment One embodiment of this invention will be described in detail with reference to the drawings. In the figure, 1 is the main body of this device, which is composed of a suspension cylinder 2, an accumulator 3, a hydraulic chamber 2a of the suspension cylinder 2,
The hydraulic chamber 3a of the accumulator 3 is communicated with each other via a pressure reducing valve 4. The interior of the accumulator 3 is divided into the hydraulic chamber 3a and the gas chamber 3e by the free piston 3b, and the gas chamber 3e is filled with nitrogen gas.

On the other hand, a pressure reducing valve 4 provided between the hydraulic chamber 2a of the suspension cylinder 2 and the hydraulic chamber 3a of the accumulator 3 includes a throttle 4a that damps the hydraulic pressure moving from the hydraulic chamber 2a to the hydraulic chamber 3a, and a throttle 4a that damps the hydraulic pressure moving from the hydraulic chamber 2a to the hydraulic chamber 3a. A check valve 4b and a relief valve 4c, which allow flow only toward the hydraulic chamber 3a, are connected in parallel, and a safety valve 5 is connected to the upstream oil passage 4d of the throttle 4a and each valve 4b, 4c. As shown in FIG. 2, the safety valve 5 has a reservoir cylinder 5b that communicates with the oil passage 4d via an oil passage 5a. The reservoir cylinder 5b has a free piston 5f that is biased toward the pressure accumulation chamber 5e by a compression spring 5d housed in a spring chamber 5c, and the spring chamber 5c is connected to a tank (not shown) via a drain 5g. It is connected. Further, in the middle of the oil passage 5a, there is a poppet 5h that allows flow only from the oil passage 4d side to the pressure accumulation chamber 5e side of the reservoir cylinder 5b, and a poppet 5h that has a smaller diameter than the poppet 5h and that connects the oil passage 4 from the pressure accumulation chamber 5e side.
Poppets 5i that allow flow only to the d side are provided in parallel, and the spring chamber 5j of the poppet 5i is communicated with the upstream side of the poppet 5h via a communication path 5k.

On the other hand, a piston 2b housed in the suspension cylinder 2 rotatably supports a spherical portion 2d formed at one end of a piston rod 2c, and the other end of the piston rod 2d is serrated on a support shaft 6. It is pivotally attached to the tip of the engaged lever 7. Further, one end of a swinging arm 8 is engaged with the support shaft 6 through serrations, so that the lever 7 and the swinging arm 8 rotate together around the support shaft 6, and the swinging arm Rolling wheel 9 on the other end side of 8
is rotatably supported.

Next, to explain the operation, when the wheel 9 is raised by receiving an external force from below, for example, the swing arm 8 and the lever 7 are rotated counterclockwise, and the hydraulic chamber of the suspension cylinder 2 is rotated. The oil in 2a is pressurized by piston 2b. This oil flows into the hydraulic chamber 3a of the accumulator 3 via the pressure reducing valve 4 and is accumulated in the accumulator 3, but when the oil pressure passes through the throttle 4a of the pressure reducing valve 4, vibrations and shocks are attenuated by the throttle 4a. be done. When the external force applied to the wheel 9 disappears, the pressure in the gas chamber 3e accumulated in the accumulator 3 pushes the oil in the hydraulic chamber 3a back into the hydraulic chamber 2a of the suspension cylinder 2 via the check valve 4b of the pressure reducing valve 4. , the swing arm 8 and the wheel 9 return to an equilibrium state.

The above is normal operation, but if abnormal pressure occurs in the pressure reducing valve 4 during the above operation, the poppet 5h provided in the middle of the oil passage 5a opens due to this abnormal pressure, and the abnormal pressure is transferred to the reservoir cylinder 5b. Accumulator chamber 5
flows into e. This allows the reservoir cylinder 5
The free piston 5f in b is pushed down against the compression spring 5j, and the abnormal pressure is accumulated in the pressure accumulating chamber 5e, so the pressure reducing valve 4 and the circuit are protected from the abnormal pressure.
When the abnormal pressure disappears, the poppet 5h is closed and the state shown in FIG. 3 is achieved. When the wheel 9 is lowered in this state, the pressure in the oil passage 4d becomes lower than the pressure in the pressure accumulation chamber 5e, so the poppet 5j opens due to the hydraulic pressure in the pressure accumulation chamber 5e, and the oil in the pressure accumulation chamber 5e flows into the oil passage. 4d
As a result, the safety valve 5 is in the state shown in FIG. 2, and the suspension device also operates normally.

Effects of the invention As detailed above, this invention has the effect that the external force applied to the road wheels from the road surface while the tracked vehicle is running causes the oil in the suspension cylinder to flow into the accumulator through the pressure reducing valve as the road wheels rise. At the same time, it is damped and absorbed by the throttle of the pressure reducing valve, and if abnormal pressure occurs in the pressure reducing valve etc. during the above operation, this abnormal pressure will accumulate in the reservoir cylinder of the safety valve, so the abnormal pressure will cause the pressure reducing valve and circuit to can be protected. Additionally, when the abnormal pressure disappears, the hydraulic pressure accumulated in the reservoir cylinder is refilled to the suspension cylinder, which may cause the suspension cylinder to run out of oil, causing the vehicle to tilt and make it difficult to drive. In addition, since it does not require a hydraulic source for oil supply, it can be implemented at low cost.

[Brief explanation of the drawing]

The drawings show one embodiment of this invention, with Fig. 1 being a sectional view, Fig. 2 being a sectional view of a safety valve provided in the pressure reducing valve, Fig. 3 being an explanatory view of its operation, and Figs. 4 and 5 being a sectional view. It is a conventional explanatory diagram. 1 is the main body, 2 is the suspension cylinder, 2a
is a hydraulic chamber, 2c is a piston rod, 3 is an accumulator, 3a is a hydraulic chamber, 4 is a pressure reducing valve, 4a is a throttle, 4
b is a check valve, 4d is an oil path, 5 is a safety valve, 5a
is an oil passage, 5b is a reservoir cylinder, 5e is a pressure accumulation chamber, and 5h and 5i are poppet valves.

Claims (1)

[Scope of utility model registration request] Suspension cylinder 2 and accumulator 3
The suspension cylinder 2 of the main body 1 consisting of
The hydraulic chamber 2a of the accumulator 3 and the hydraulic chamber 3a of the accumulator 3 are communicated with each other via a pressure reducing valve 4, and a piston rod 2c protrudes from the suspension cylinder 2.
The tip of the pressure reducing valve 4 is linked to a swinging arm 8 having a rolling wheel 9 attached to the tip.
The pressure accumulation chamber 5e of the reservoir cylinder 5b is communicated with the upstream oil passage 4d of the throttle 4a and check valve 4b provided in the reservoir cylinder 5b through the oil passage 5a, and the pressure accumulation chamber 5e is connected to the reservoir cylinder 5b by a compression spring 5d. A piston 5f biased toward the pressure accumulating chamber 5e side is provided, and a poppet valve 5h is provided in the middle of the oil passage 5a, which flows only from the oil passage 4d side to the pressure accumulating chamber 5e side of the reservoir cylinder 5b, and an oil passage 4d is provided from the pressure accumulating chamber 5e side. A hydroneumatic suspension device for a tracked vehicle, which is provided with poppet valves 5i in parallel that allow flow only to the side.