JPH0728432Y2 - Hydraulic suspension unit - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a hydraulic suspension unit which is provided between a vehicle body and an axle of a vehicle and which can adjust the vehicle height and the vehicle posture by performing a stretching stroke.

[Prior Art] Conventionally, as a hydraulic suspension unit, for example,
The one described in JP-A-63-106440 is known.

This conventional hydraulic suspension unit is a unit having an upper end connected to a vehicle body side of a vehicle and a lower end connected to an axle side of a vehicle, and formed so that an air spring effect by an accumulator can be obtained when expanding and contracting. A manual pilot check valve is arranged in a flow passage formed so as to supply and discharge the hydraulic pressure from the hydraulic pressure supply source into the unit main body.

This manual pilot check valve has a steel ball biased by a spring and a bolt having a valve seat surface on which the steel ball is seated. It has a connecting rod that moves forward and backward by a joint operation and contacts the steel ball when it advances to open the valve.

[Problems to be Solved by the Invention] However, the conventional hydraulic suspension unit has a structure in which a manual pilot check valve is provided in the flow path that connects the main body and the hydraulic pressure supply source. , There are problems listed below.

That is, first, when assembling the hydraulic suspension unit to the vehicle, the operation dial must be screwed in and the steel ball must be opened via the connecting rod.

In addition, it is necessary to loosen the operation dial when detaching for replacement, which is also inferior in workability.

SUMMARY OF THE INVENTION An object of the present invention is to provide a hydraulic suspension unit capable of solving the conventional problems and improving the workability of assembling and dismounting.

[Means for Solving the Problems] In order to achieve the above object, the present invention has an upper end connected to a vehicle body side of a vehicle, a lower end connected to an axle side of the vehicle, and a liquid flow from a hydraulic pressure supply source. In a hydraulic suspension unit that adjusts and supports the vehicle body height according to the supply / discharge amount of hydraulic fluid supplied to / discharged from a pressure chamber via a passage, a spool body having a valve accommodating hole is provided in the liquid passage, A spool having a plurality of lands is slidably fitted in the valve accommodating hole to divide the valve accommodating hole into at least three chambers, and two of these three chambers are provided with the hydraulic pressure supply source for the liquid flow path. Side and the pressure chamber side, and the other chamber is a constant pressure chamber, and
An urging means for urging the spool from the constant pressure chamber side to the pressure supply source side is provided, and normally, the liquid pressure supply side and the pressure chamber side of the liquid flow path are shut off and the liquid pressure supply is performed. When the pressure on the source side reaches a predetermined pressure, the spool is moved against the urging force of the urging means so that the hydraulic pressure supply source side of the liquid flow path and the pressure chamber side communicate with each other. Configured.

[Operation] According to the present invention, when the hydraulic suspension unit exists as a single unit before it is assembled to the vehicle, the pressure of the hydraulic pressure supply source does not work, so that the liquid in the liquid flow path of the hydraulic suspension unit is not affected. The pressure supply side and the pressure chamber side of the hydraulic suspension unit are closed by a spool, and the leakage of the hydraulic fluid filled in the unit is prevented. Therefore, it is possible to carry the hydraulic fluid while the unit is filled with the hydraulic fluid.

Even if the hydraulic suspension unit is installed in the vehicle in the above state and the hydraulic flow path is connected to the hydraulic pressure supply source, the spool valve is installed in the constant pressure chamber unless pressure is applied from the hydraulic pressure supply source. The fluid pressure supply side and the pressure chamber side are closed by being biased by the biasing means.

Then, when pressure is applied from the hydraulic pressure supply source, the spool valve slides against this pressure against the biasing means and automatically connects the hydraulic pressure supply source side and the pressure chamber side to the liquid flow path. It is opened, whereby the hydraulic fluid is supplied to and discharged from the pressure chamber, and it can operate as a hydraulic suspension.

Embodiments Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a cross-sectional view showing a hydraulic suspension unit according to an embodiment of the present invention. The hydraulic suspension unit is provided at four locations on a vehicle body, that is, a support side member for four wheels of a vehicle body (not shown) and a vehicle body. And are provided respectively.

In the figure, 1 is a cylinder tube, 2 pistons, 3 is a piston rod, 4 is an outer cylinder, 5 is an accumulator, 6 is a pressure control valve, and 7 is a hydraulic pressure supply source.

A bottom body 8 is fitted to the lower end of the cylinder tube 1, and a guide member 9 is fitted to the upper end thereof to form a pressure chamber 1a therein.

A rod insertion port 9a is formed in the guide member 9, and the piston rod 3 is inserted into the pressure chamber 1a from there.

The piston rod 3 is formed in a hollow shape having a supply / discharge passage 3a for supplying / discharging hydraulic fluid, the upper end is attached to a vehicle body (not shown), and the piston 2 is fastened to the lower end by a nut 2a. Has been done. A stopper 2b is attached to an appropriate position below the piston rod 3.

The piston 2 is slidably provided by partitioning the pressure chamber 1a of the cylinder tube 1 into an upper chamber 1b and a lower chamber 1c.

The outer cylinder 4 encloses the cylinder tube 1 and the piston rod 3, and the liquid recovery chamber is provided on the outer periphery of the cylinder tube 1.
4a is formed, the lower end is fitted to the outer periphery of the bottom member 13, the upper end is fitted to the outer periphery of the guide member 9, and further closed by the atmospheric pressure seal 14 and the packing land 15. Has been done. The outer cylinder 4 is attached to an axle side member (not shown) by an attachment ring 4c fixed to the bottom member 13.

The liquid leakage recovery chamber 4a has a structure in which the liquid leakage outlet 4b formed in the outer cylinder 4 recovers the liquid from the tank T. The bottom member 13 is fitted around the bottom body 8 and the cylinder tube 1.

A pressure reducing seal 9b and an O-ring 9c are inserted on the inner peripheral surface of the guide member 9.

The decompression seal groove 9d for accommodating the decompression seal 9b and the O-ring 9c is formed by the inner circumference of the guide member 9 and the stopper 16 press-fitted into the inner circumference of the guide member 9.

A flange 16a is formed at the lower end of the stopper 16 so as to have an L-shaped cross section, and the pressure reducing seal groove 9d is formed by press-fitting the flange 16a until the flange 16a comes into contact with the lower end surface of the guide member 9. Is determined.

In addition, the guide member 9 located above the decompression seal 9b
A guide bush 9e is press-fitted into the inner circumference, and the piston rod 3 is inserted into the inner circumference of the guide bush 9e. Then, the piston rod 3 and the guide member 9
A liquid storage chamber 9f for storing the liquid leaked from the guide bush 9e is formed between and the atmospheric pressure seal 14. The liquid storage chamber 9f communicates with the liquid leakage recovery chamber 4a via a communication port 9g formed in the guide member 9.

In addition, a packing land is provided in the upper end opening of the outer cylinder 4.
15 is screwed in, and an annular holding plate 14a for holding the atmospheric pressure seal 14 is sandwiched between the lower end surface of the packing land 15 and the upper end surface of the guide member 9.

Next, the stopper 2b is a nut together with the piston body 2c.
The piston 2 is fastened to the piston rod 3 at 2a to form the piston 2.

The piston body 2c is provided with a plurality of orifice holes 2d and a communication port 2e for communicating the upper chamber 1b and the lower chamber 1c. Then, at the lower opening end of the orifice hole 2d, the valve is opened by a predetermined hydraulic pressure difference, and the upper chamber 1b to the lower chamber are opened.
A valve disc 2f that allows only the flow of the working fluid to 1c is provided, and the orifice hole 2d and the valve disc 2f constitute an extension side damping valve.

A check plate 2g is provided at the upper opening end of the communication port 2e to form a one-way valve.

Further, the bottom body 8 forms a bottom chamber 8a defined between the bottom member 8 and the lower chamber 1c.

Sealing members 8b and 8c are provided between the bottom body 8 and the cylinder tube 1 and between the bottom body 8 and the bottom member 13, respectively. Leakage recovery room
4a and the bottom chamber 8a are shut off. Further, a communication port 13a is opened in the bottom member 13.

Further, the bottom body 8 is provided with a compression damping valve 80. That is, the bottom body 8 has a valve body 8d.
Are fastened with bolts, and the valve body 8d is provided with an orifice hole 8e and a communication port 8f.
A valve disk 8g is provided at the lower opening end of the orifice hole 8e to open the valve due to a predetermined hydraulic pressure difference and allow the working fluid to flow from the lower chamber 1c to the bottom chamber 8a. The compression damping valve 80 is constituted by 8e and the valve disk 8g.

A check plate 8h is provided at the upper open end of the communication port 8f to form a one-way valve.

The accumulator 5 acts as a gas spring, and in this embodiment, as shown in FIG. 1, a cylinder tube chamber 5d composed of a cylindrical cylinder tube body 5a, a head 5b and a bottom 5c is provided with a free piston. A free piston type in which an upper gas chamber 5f and a lower liquid chamber 5g are partitioned by 5e and a communication port 5h is opened is used for the bottom 5c.

The head 5b and the bottom 5c of the accumulator 5 are attached to the outer cylinder 4 and the attachment ring 4c via brackets 5j and 5k, respectively, and the lower liquid chamber 5g and the bottom chamber 8a are connected to each other. The connection pipes 17 are connected between the communication ports 5h and 13a.

Further, a radial path 3b communicating with the supply / discharge path 3a is bored at an upper position of the piston rod 3, and a connector 18 is attached to the radial path 3b. Then, one end of a steel pipe 19 is connected to the connector 18 by welding, and the other end is also connected to the spool body 20.

The spool body 20 is provided with axial stepped through holes 20a, 20b and 20c which form a valve accommodating hole, a radial communicating hole 20d which communicates with the above-mentioned steel pipe 19, and a port 20e.
The spool 21 having the first and second lands 21a and 21b having different diameters is fitted into the stepped through hole, and the spool accommodating hole is provided with a hydraulic pressure source side chamber 26, a pressure chamber side chamber 27 and a constant pressure chamber 28. It is divided into At the end of the spool body 20 where the large diameter side through hole 20a is present, a cap 22 having a communication hole 22a for communicating the constant pressure chamber 28 with the outside air is screwed, and the cap 22 and the large diameter side first hole are formed. A spring 23 as a biasing means for biasing the spool 21 downward is contracted between the first land 21a and the first land 21a.

Then, in the state of being biased by the spring 23, the small diameter side second land 21b of the spool 21 is engaged and held at the step portion with the stepped through holes 20b and 20c, and is connected to the other passage of the communication hole 20d. The communication is blocked by the first and second lands 21a and 21b. O-rings 21c and 21d for sealing are attached to the first and second lands 21a and 21b, respectively. Thus, the spool body 20 and the spool 21 constitute a valve device.

The port 20e is used for evacuation, and a plug 24 having a sealing member is screwed into the port 20e.

Then, a connector (not shown) is screwed to the lower end of the spool body 20, and is connected to the output circuit 10 forming the liquid flow path through the stepped through holes 20c and 20b, the steel pipe 19 and the connector 18, and the supply / discharge path. 3a is connected and communicated.

Hydraulic fluid is supplied to and discharged from the hydraulic pressure supply source 7 via the pressure control valve 6 to the output circuit 10. The pressure control valve 6 has a hydraulic pressure supply circuit 11
And a drain circuit 12 reaching the tank T are selectively connected to the output circuit 10 to provide a spool valve for controlling the output hydraulic pressure.

The hydraulic pressure supply source 7 is composed of a pump driven by an engine or the like, an accumulator that absorbs pulsation of discharge pressure from the pump, and the like.

Next, in the present embodiment having the above-described configuration, first, when the hydraulic suspension unit is present as a single unit, that is, when the spool body 20 and the output circuit 10 are not connected, the spool 21 has the spring 23. And is in the state shown in FIG.

Therefore, in such a state, the flag 24 is removed, and the working fluid is injected into the hydraulic suspension unit while evacuating the port 20e. Then, even though the necessary portion of the unit is filled with the hydraulic fluid, the communication between the steel pipe 19 and the other passage of the communication hole 20d is not achieved by the first and second lands 21 of the spool 21.
Since it is blocked by a and 21b, it can be shipped as it is.

Next, the hydraulic suspension unit in the above state is attached to the vehicle, and the spool body 20 and the output circuit 10 of the hydraulic circuit are connected by the connector 25 as shown in FIG.
Then, the inside of this hydraulic circuit is similarly evacuated to inject the working fluid. When the hydraulic fluid is injected and filled, the hydraulic fluid reaches the lower end surface of the second land of the spool 21, but since no pressure is generated, the spool 21 does not move and is maintained in the second illustrated state. It

Then, once the engine rotates and the pump 7 operates, pressure is generated in the hydraulic circuit, and the spool 21 moves against the spring 23 into the large diameter through hole 20a as shown in FIG.
Then, the supply / discharge path 3a and the output circuit 10 of the hydraulic circuit are communicated with each other, the amount of liquid in the pressure chamber 1a of the hydraulic suspension unit is controlled based on the pressure controlled by the pressure control valve 6, and the vehicle height and the vehicle attitude are controlled. Etc. are adjusted.

Although the spring 23 is provided for holding the position of the spool 21 in the above-described embodiment, this is not always necessary, and for example, an O-ring mounted on the land is provided with friction sufficient to hold the position. It should be generated. In this case, the first and second lands 21a and 21b
It is preferable to make the diameters of the two equal.

When removing the hydraulic suspension unit from the vehicle, the spool 21 located in the large-diameter through hole 20a is moved to the flow path closing position.
It is sufficient to simply push it in with a rod or the like.

[Effects of the Invention] As is apparent from the above description, according to the present invention, the upper end is connected to the vehicle body side of the vehicle, the lower end is connected to the vehicle axle side, and the liquid flow path is connected to the liquid flow path. In a hydraulic suspension unit that adjusts and supports the vehicle body at a predetermined height according to the supply / discharge amount of hydraulic fluid supplied to / discharged from the pressure chamber via a spool body having a valve accommodating hole in the liquid flow path, A spool having a plurality of lands is slidably inserted into the valve accommodating hole to divide the valve accommodating hole into at least three chambers, and two of these three chambers are supplied with the hydraulic pressure of the liquid flow path. The source side and the pressure chamber side are connected to each other, the other chambers are formed as constant pressure chambers, and a biasing means for pressing and biasing the spool from the constant pressure chamber side to the pressure supply source side is provided. While blocking the liquid pressure supply side and the pressure chamber side of the liquid flow path, When the pressure on the hydraulic pressure supply side reaches a specified pressure,
Since the spool is moved against the urging force of the urging means so that the hydraulic pressure supply source side of the liquid flow path and the pressure chamber side communicate with each other, the hydraulic suspension unit unit is configured to store the hydraulic fluid. It is possible to ship in a filled state, keep the inside in a good lubricating state, and inject hydraulic fluid only into the hydraulic circuit after mounting it on the vehicle body, and in addition to being able to finish the work in a short time, Since the valve device opens automatically, no special work is required for it, and workability is significantly improved.

[Brief description of drawings]

1 is a sectional view showing a hydraulic suspension unit according to an embodiment of the present invention, FIG. 2 is an enlarged sectional view of an essential part showing a connection state of a hydraulic suspension circuit of the embodiment unit of the present invention, FIG. FIG. 4 is an enlarged cross-sectional view of a main part showing a pressure generation state in a connection state of the embodiment unit of the present invention with a hydraulic circuit. 1 ... Cylinder tube, 1a ... Pressure chamber, 2 ... Piston, 3 ... Piston rod, 3a ... Supply / discharge passage, 5 ... Accumulator, 6 ... Pressure control valve, 7 ... Fluid pressure supply source, Ten
...... Output circuit (liquid flow path), 20 …… Spool body, 20a,
20b, 20c …… Stepped through hole (valve housing hole), 21 …… Spool, 21a, 21b …… Land, 26 …… Hydraulic pressure source side chamber, 27…
… Pressure chamber side chamber, 28 …… Low pressure chamber.

Claims (1)

[Scope of utility model registration request] 1. A supply / drainage of a hydraulic fluid, the upper end of which is connected to a vehicle body side, the lower end of which is connected to an axle side of the vehicle, and which is supplied / discharged from a hydraulic pressure supply source to a pressure chamber via a liquid flow path. In a hydraulic suspension unit that adjusts and supports the vehicle body at a predetermined height according to the amount, a spool body having a valve accommodating hole is provided in the liquid flow passage, and a spool having a plurality of lands is slidable in the valve accommodating hole. The valve accommodating hole by at least 3
While being divided into chambers, two of these three chambers are connected to each of the liquid pressure supply source side and the pressure chamber side of the liquid flow path, and the other chamber is a constant pressure chamber, and An urging means for urging the spool from the constant pressure chamber side to the pressure supply source side is provided, and normally, the liquid pressure supply side and the pressure chamber side of the liquid flow path are shut off, and the liquid pressure supply source is provided. When the side pressure reaches a predetermined pressure, the spool is moved against the urging force of the urging means so that the hydraulic pressure supply source side of the liquid flow path and the pressure chamber side communicate with each other. A hydraulic suspension unit that has been characterized.