JPH0437301B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a self-feeding hydraulic suspension column with internal height control.

[Conventional technology]

a working cylinder filled with buffer oil and divided into first and second working chambers by a force-transmitting piston, said piston being slidable within the working cylinder and mounted at the end of a hollow piston rod; , a pump cylinder is installed inside the hollow piston rod, and a pump rod operating inside the pump cylinder is fixedly attached to the bottom of the working cylinder, and the center of the pump rod communicates with the low pressure chamber. a small hole passing through the pump cylinder, and a suction valve at an end within the pump cylinder, the first working chamber communicating on one side with a high pressure chamber, the high pressure chamber adjoining the gas high pressure chamber via a diaphragm. , on the other hand, communicates with the low-pressure chamber via a passage through the small through-hole in the pump rod, the throttle valve, the suction valve and the pressure valve, so that when the piston passes a suitable position in the working cylinder, the high-pressure chamber is penetrated. The present invention relates to a self-contained suction oil-pneumatic suspension column with internal height control that is fully open to a low pressure chamber through small holes, throttle valves and control openings.

In the as-yet-unpublished German patent application No. P3306393.1-21, a throttle valve has already been proposed which is arranged in the end area of the pump rod.

[Problem to be solved by the invention]

In such a structural arrangement, the manufacture of a pump rod with a portion that retards the oil discharge is expensive, additional modifications are required in the surface treatment of the pump rod, and small external parts are required. The disadvantage is that only limited machining lengths are possible for pump rods of this diameter.

The object of the invention is to overcome the disadvantages of suspension struts of the above-mentioned type and to provide a pump rod of construction with a surface that can be quickly and easily machined, and which is overall simple in construction and reliable. The purpose of the present invention is to provide a durable suspension support.

[Means and actions to solve the problem]

According to the present invention, the pump rod comprises a component having first and second long through holes, the components are connected end to end by fitting, and the pump rod has a first configuration. the end of the element remote from the connection with the second component is clamped to the bottom of the working cylinder, and the end of the second component remote from the connection is provided with a suction valve; Internal height controllable, characterized in that the throttle valve acts only in one direction and is provided in the connecting part between the first and second components with respect to the through hole of the pump rod. This is accomplished by means of self-controlled hydraulic and pneumatic suspension struts.

Packing the throttle valve inside the pump rod made the unit stronger and made the pump rod itself two parts. Furthermore, by moving the throttle valve away from the suction valve and into the area of the two-part piston rod, a substantially shorter component is achieved and the throttle valve is easier to process and cheaper to manufacture. Become.

The assembled pump rod can consist of a textured portion (actual pump rod) and a non-surfaced portion (extension portion). This means that
Allows the production of longer overall length pump rods with small outer diameters.

Preferably, the first component of the pump rod extends into a recess in the end of the second component, and the end of said second component is crowned in a groove on the outside of the first component. It is desirable to be worn.

In yet another embodiment, an outer groove of the first component accommodates a packing. In this way, the groove can be simply produced in the final machining of the components of the pump rod to be brought together.

In a further preferred embodiment, the throttle valve is provided with a V-shaped notch in a valve seat provided on one of the components of the pump rod and a cut-out around the periphery with a valve head that engages with said valve seat. It is formed as a result.

Hereinafter, preferred embodiments of the present invention will be described based on the drawings.

The height-controllable self-fed hydraulic pneumatic suspension strut of a motor vehicle shown in FIG. is slidably mounted. The working cylinder 1 is closed at one end by a bottom 4 and at the other end by a lid 5 through which a hollow piston rod 3 extends outwardly and is sealed on the outside. Although the suspension strut is normally mounted on a motor vehicle with the lid 5 at the top, in this case the bottom 4 is shown as the top.
The bottom part 4 is fixed to the body of the motor vehicle by means of a fastening pin 6, and the piston rod 3 is fixed to the axle of the motor vehicle by means of a mounting ring 7 in a manner not shown.

The working cylinder 1 is surrounded by an annular compensation chamber, partly filled with oil and partly with gas, which is divided by a partition 8 into a high-pressure chamber 11, 9 and a low-pressure chamber 10. be done.

The high pressure chamber includes a gas high pressure chamber 9 separated by a diaphragm 12 from an oil chamber 11 . Low pressure chamber 10
Inside there is an oil and low pressure gas chamber 13, the oil level being indicated at 14. In a completely low pressure state, i.e. before being pumped up, the pressure in the low pressure chamber 10 is the same as that existing in the high pressure chambers 11,9.

The working piston 2 connects the working cylinder 1 to the first and second
It is divided into working chambers 16 and 18. First working chamber 1
6 is located between the working piston 2 and the bottom 4 and communicates with the high pressure oil chamber 11 through a passage 17. A second working chamber 18 is located between the working piston 2 and the lid 5 and cooperates with the first working chamber 16 of the working cylinder 1 through a valve located in the forwardly arranged working piston 2.

The pump rod 19 is fastened to the bottom 4 by an elastic support 20, and the pump rod 19 is slidable into a control tube 32 provided in the hollow space of the piston rod 3, which is connected to the pump cylinder of the oil pump. Form 21. The movement of the axle caused by the undulations of the road and the corresponding movement of the piston rod 3 fixed to the axle actuate this oil pump, which pumps oil from the low pressure chamber 10 to the small hole in the pump rod 19. through a suction valve 22 at the end of the pump rod 19, a pressure valve 23 and a passage 24 into the first working chamber 16. In this way, the working piston 2, the piston rod 3,
and the control tube 32 is moved outward until it reaches a predetermined position in the cylinder when the control opening 25 in the pump rod 19 is in communication with the first working chamber 16 and uncovered. In that way, the first
The working chamber 16 includes a throttle valve 27 together with the low pressure chamber 10.
(more apparent in FIG. 2) and communicates with the high pressure chamber through a small through hole 19 in the pump 19.

In FIG. 2, the pump rod 19 is shown enlarged. The pump rod 19 consists of first and second components 19a and 19b, which are connected to each other by a crowning portion 26. The first component 19a is the second component 1
The end of the second component 19b which projects into the chamber 28 of 9b is deformed and is, for example, crowned in a groove 29 in the first component 19a. This deformation work is performed, for example, by caulking. This groove 29 is also used to accommodate a gasket 30 that seals between the control tube 32 and the pump rod 19.

Near the connection of both components 19a and 19b of the pump rod 19, a throttle valve 27 is arranged in the cavity 33. This throttle valve essentially consists of a recess in the valve seat which is engaged by the valve head 31. The valve head 31 is smooth or has its periphery cut off so that oil pumping is not restricted.

〔Effect of the invention〕

The invention has made it possible to provide a generally simple, reliable and robust device at low cost, having a pump rod structure with a surface that can be quickly and easily machined.

[Brief explanation of drawings]

Fig. 1 is a sectional view showing a self-controlled oil-feeding hydraulic pneumatic suspension strut with internal height adjustment according to the present invention, and Fig. 2 is an enlarged side sectional view of the pump rod divided into two parts of the suspension strut of Fig. 1. It is. 1... Working cylinder, 2... Piston, 3...
Hollow piston rod, 9... Gas high pressure chamber, 10
...Low pressure chamber, 11 ... Oil high pressure chamber, 13 ... Resistant pressure gas chamber, 16, 18 ... Working chamber, 19 ... Pump rod, 19a ... First component, 19b ... Second
Components of 22... Suction valve, 25... Control opening, 26... Crowning portion, 27... Throttle valve, 28...
...Komuro, 29...Mizo, 30...Patsukin.

Claims (1)

[Scope of Claims] 1. A working cylinder 1 filled with buffer oil and divided into first, 16th and second, 18th working chambers by a force-transmitting piston 2; A pump cylinder 21 is installed inside said hollow piston rod 3, and a pump rod 19 operating in the hollow part of said pump cylinder 21 is attached to the end of said hollow piston rod 3. It is firmly fastened to the bottom 4,
It also has a small hole 19c passing through the center of the pump rod communicating with the low pressure chamber 10, and a suction valve 22 at the end inside the pump cylinder, so that the first working chamber 16 is connected to the high pressure chamber 1 on one side.
1, the high pressure chamber 11 is adjacent to the gas high pressure chamber 9 via the diaphragm 12, and on the other hand, the small through hole 19c of the pump rod, the throttle valve 27, and the suction valve 22.
and through the pressure valve 23 and through the passage 24 to the low pressure chamber 10, so that when the piston 2 passes a suitable position within the working cylinder 1, the high pressure chamber 11 is connected to the through hole 29c, the throttle valve 27 and the control A component in which the pump rod has a first, 19a and a second, 19b long through-hole in a self-controlled oil-feeding pneumatic suspension column with internal height control that is fully open to the low-pressure chamber 10 through an opening 25. , the components are connected end to end by fitting, and the first component 1
The end of 9a remote from the connection with the second component 19b is clamped to the bottom of the working cylinder, and the end of the second component 19b remote from said connection has a suction valve 22. provided, characterized in that a throttle valve 27 acts only in one direction of flow and is provided for the through-hole of the pump rod at the connecting part between the first and second components. Self-controlled oil-fed pneumatic suspension column with internal height control. 2 the first component 19a of the pump rod extends into a recess 28 in the end of the second component 19b;
In turn, an end of the second component is connected to the first
An internal height controllable self-fed hydraulic pneumatic suspension strut according to claim 1, wherein the internal height controllable self-fed hydraulic suspension strut is mounted in an outer groove 29 of the component. 3. Self-fed hydraulic pneumatic suspension with internal height control, characterized in that the outer groove 29 of the first component simultaneously accommodates a packing 30. Prop. 4. Said throttle valve 27 is formed by a V-shaped notch in the valve seat at one end of the pump rod component and a valve head 31 that engages with the valve seat, the valve head having its periphery cut away. A self-controlled oil-feeding hydraulic pneumatic suspension column with internal height control, as claimed in any one of claims 1 to 3.