JP3746557B2 - Vehicle height adjustment device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention is interposed between the vehicle body and the axle of the vehicle and attenuates vibrations from the road surface in a normal state, and always controls the vehicle height constant regardless of the sprung load, The present invention relates to a vehicle height adjusting device capable of further lowering the vehicle height when a passenger gets on and off.
[0002]
[Prior art]
As this type of vehicle height adjusting device, for example, the one disclosed in FIG. 2 has been developed. In this vehicle height adjusting device, the control orifice 1C is set at a position that does not cover the pump cylinder 11 at the standard vehicle height of the vehicle. When the sprung load increases due to loading or the like, the shock absorber S contracts as the vehicle height decreases, and the control orifice 1C and the notch 1B enter the pump cylinder 11. When traveling, the shock absorber S is vibrated by the unevenness of the road surface. However, in the extension stroke of the shock absorber S in a state where the vehicle height is lowered, the hydraulic oil in the rod side chamber C passes through the piston 6 with the damping valve and the anti-rod side chamber B. The hydraulic oil corresponding to the withdrawal volume of the piston rod 12 is sucked from the reservoir F through the suction pipe 8, the passage 5 </ b> A formed in the upper part of the outer shell 5, and the hollow hole 1 </ b> A formed inside the pump rod 1. The valve 9 is opened and sucked into the pump chamber A where the pressure is negative.
[0003]
In the contraction stroke of the shock absorber S, the hydraulic oil in the pump chamber A is discharged from the discharge valve 13 and flows to the non-rod side chamber B through the passage 11A between the piston rod 12 and the pump cylinder 11. As the amount of oil in the anti-rod side chamber B increases due to this repetition, the anti-rod side chamber B is formed between the communication hole 2A formed in the disc-like plate 2 that seals the upper end of the cylinder 3 and between the cylinder 3 and the cap 4. The oil chamber E communicates with the passage 3A. Here, the oil chamber E is partitioned from a high-pressure gas chamber D filled with an inert high-pressure gas through a boot 7 as a contractible partition wall, and an oil chamber of an accumulator formed in the shock absorber S It has become.
[0004]
As a result of the expansion of the boot 7 by the internal pressure of the oil chamber E, the volume of the high-pressure gas chamber D is reduced and the pressure increases, and the pressure in the high-pressure gas chamber D balances with the oil chamber E via the boot 7 and communicates therewith. The pressure in the non-rod side chamber B also increases. Therefore, the repulsive force of the piston rod 12 increases, and the shock absorber S extends corresponding to the increased repulsive force, so that the vehicle height increases. When the shock absorber S extends and a notch passage 1B formed by partially scraping the outer surface of the pump rod 1 goes out of the pump cylinder 11, the pump chamber A and the non-rod side chamber B are connected via the notch passage 1B. Therefore, the vehicle height does not increase any further.
[0005]
Next, when the sprung load decreases by unloading the load or the like, the shock absorber S extends at a speed buffered by the piston 6 with the damping valve attached to the upper end of the piston rod 12 due to the repulsive force of the piston rod 12 and is controlled. The orifice 1C goes out of the pump cylinder 11. From this state until the control orifice 1C enters the pump cylinder 11 and is closed, the hydraulic oil in the anti-rod side chamber B passes through the control orifice 1C and the hollow hole 1A formed inside the pump rod 1 and the suction pipe 8 After that, the pressure returns to the reservoir F, so that the pressure in the anti-rod side chamber B decreases and the repulsive force of the piston rod 12 also decreases.
[0006]
Reference numeral 10 denotes a rod guide. A cylinder 3 and a boot 7 are attached to a small diameter stepped portion at the upper end thereof, and two stages of seals 15 and 16 are attached to the inside thereof, and a bush 17 is press-fitted into the upper end. Thus, the piston rod 12 is slidably guided. Reference numeral 14 denotes a fastening nut that fixes the rod guide 10 to the outer shell 5, and 18 denotes a dust boot that protects the piston rod from dust.
[0007]
[Problems to be solved by the invention]
In the shock absorber S described in the prior art, after the vehicle height adjusting action is completed, the anti-rod side chamber B becomes a pressure corresponding to the load and the occupant weight, and the vehicle body maintains the standard vehicle height. However, since there is no means for forcibly reducing the pressure in the anti-rod side chamber B, it is impossible to satisfy the demand for further lowering the vehicle height for loading and unloading of luggage and passengers getting on and off. There was a problem.
[0008]
SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to make a vehicle capable of facilitating the loading and unloading of luggage and the getting on and off of passengers by further lowering the vehicle height at the time of loading and unloading of luggage and passengers getting on and off the vehicle. It is to provide a high adjustment device.
[0009]
[Means for Solving the Problems]
In order to achieve the above object, the means of the present invention comprises a shock absorber, an accumulator, a pump mechanism, a control orifice, and an opening / closing means.
The shock absorber is partitioned by a cylinder, an outer shell disposed outside the cylinder, a reservoir partitioned inside the outer shell, a piston rod movably inserted into the cylinder via a piston, and a piston within the cylinder. The rod side chamber and the anti-rod side chamber,
The accumulator is composed of a high pressure gas chamber, and an oil chamber communicating with the rod side chamber while being separated from the high pressure gas chamber via a boot,
The pump mechanism includes a pump rod that is inserted into the piston rod so as to be stretchable and supplies the pressure oil of the reservoir to the anti-rod side chamber and the oil chamber of the accumulator when the shock absorber is stretched.
A control orifice is formed in the pump rod to communicate the anti-rod side chamber with the reservoir at a predetermined position to control the shock absorber to a predetermined height,
The opening / closing means is a vehicle height adjustment device that communicates or shuts off the oil chamber of the accumulator with the reservoir when loading / unloading luggage and getting on / off of passengers.
The opening / closing means includes a valve seat fixed to the outer periphery of the cylinder, a high pressure port and a low pressure port formed in the valve seat, and the high pressure port and the low pressure port formed in the cylinder to connect the oil chamber of the accumulator and the above It is characterized by comprising two communication holes communicating with the reservoir, and a solenoid valve for communicating or blocking the high pressure port and the low pressure port.
In this case, a cap for separating the accumulator oil chamber and the reservoir is provided between the outer shell and the cylinder, and another communication hole is formed in the cap for communicating the high-pressure port and the communication hole with the oil chamber of the accumulator. May be.
Similarly, the solenoid valve is preferably a two-port solenoid valve that is controlled by a push button provided in the vehicle interior or controlled in conjunction with opening / closing of a luggage compartment door.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
A vehicle height adjusting device according to the present invention will be described below with reference to an embodiment shown in FIG. Since the operation and effect of the shock absorber body are the same as those of the prior art described above, the description thereof is omitted.
The vehicle height adjusting device of the present invention includes a shock absorber Sa , an accumulator, a pump mechanism, a control orifice 1c, and an opening / closing means, as in the prior art .
The shock absorber Sa includes a cylinder 3, an outer shell 105 disposed outside the cylinder 3, a reservoir F partitioned inside the outer shell 105, and a piston rod 12 movably inserted into the cylinder 3 via a piston 6. When formed by a rod-side chamber C and anti rod-side chamber B partitioned by the piston 6 in the cylinder 3, the accumulator is 隔成through the high pressure gas chamber D, the high pressure gas chamber D and boots 7 while the rod Consists of an oil chamber E communicating with the side chamber B ,
The pump mechanism includes a pump rod 1 which is inserted into the piston rod 12 so as to be extendable and contracted , and supplies pressure oil in the reservoir F to the anti-rod side chamber B and the oil chamber E of the accumulator when the shock absorber Sa is expanded and contracted. ,
The control orifice 1c is formed in the pump rod 1, and communicates the anti-rod side chamber B with the reservoir F at a predetermined position to control the shock absorber Sa to a predetermined height.
The opening / closing means communicates or shuts off the oil chamber E of the accumulator with the reservoir F when loading / unloading luggage or getting on / off of passengers .
In the present invention, the opening / closing means is formed in the valve seat 120 fixed to the outer periphery of the cylinder 3, the high pressure port 120 A and the low pressure port 120 B formed in the valve seat 120, and the cylinder 3. Two communication holes 105 A and 105 B communicating the high pressure port 120 A and the low pressure port 120 B with the oil chamber E and the reservoir F of the accumulator , respectively , and the high pressure port 120 A and the low pressure port 120 B communicating with each other. Or it comprises the solenoid valve 123 which interrupts | blocks, It is characterized by the above-mentioned.
[0011]
A packing 121 is disposed on the joint surface of the outer shell 105 and the valve seat 120 on the high pressure port 120A side, and a packing 122 is disposed on the joint surface on the low pressure port 120B side to prevent leakage of hydraulic oil from the joint surface. For this reason, the valve seat 120 does not necessarily need to be welded to the outer surface of the outer shell 105, and only a portion necessary for holding needs to be welded, so that the welding process is simplified.
Similarly, a packing 127 is disposed on the outer periphery of the cap 104 to prevent leakage of hydraulic oil between the annular groove 104B connected to the high pressure port 120A and the reservoir F.
[0012]
The two-port solenoid valve 123 is normally shut off by the return spring 123D, but when the cargo is loaded or unloaded or a passenger gets on or off, the push button switch 125 in the passenger compartment is operated to activate the solenoid 123C, thereby The oil chamber E and the anti-rod side chamber B of the shock absorber and the reservoir F can be forcibly communicated so that the vehicle height can be lowered further than the standard vehicle height. It is possible to facilitate getting on and off.
[0013]
In passenger cars with back doors such as van-type commercial vehicles, when you want to automatically lower the vehicle height when loading / unloading luggage in the luggage compartment, the mechanical state that becomes conductive by opening the back door A contact (for example, a limit switch) is disposed between the vehicle body frame and the back door, and the solenoid 123C is automatically operated to achieve the object. This is illustrated by the mechanical contact 126 in FIG. FIG. 1B illustrates a case where the push button switch 125 and the mechanical contact 126 in the vehicle interior are connected in parallel so that the solenoid 123C can be operated from either side, but both are not necessarily used in parallel. However, it is not necessary to use either one, or both may be used in series depending on the purpose of use of the vehicle.
[0014]
Further, since the two-port solenoid valve 123 is symbolized and displayed, the two-port solenoid valve 123 and the high-pressure port 120A and the low-pressure port 120B are connected by pipe lines 123A and 123B. Is assembled to the shock absorber by tightening the valve body of the two-port solenoid valve to a mounting screw 120C provided on the valve seat with a mounting bolt (not shown).
[0015]
Although FIG. 1 illustrates the case where the accumulator is formed in the shock absorber, the accumulator may be provided separately from the shock absorber body. That is, the object of the present invention can be achieved by adding an opening / closing means for forcibly communicating or blocking the oil chamber of the accumulator and the anti-rod side chamber of the shock absorber and the reservoir, so that the structure of the shock absorber is not limited. It is only necessary to add an opening / closing means. Since the opening / closing means is not limited, for example, a 2-port solenoid valve can be replaced with a 2-port pilot valve controlled by air pressure or the like. In this case, the power source 124 of FIG. 1 is replaced with a pneumatic source, and the push button 125 and the mechanical contact 126 are replaced with a pneumatic valve.
[0016]
【The invention's effect】
As described above in detail, in the present invention, a self-level that keeps the vehicle height constant only by adding an opening / closing means for forcibly communicating or blocking the anti-rod side chamber of the shock absorber and the reservoir with a self-level adjustment function. Without impairing the adjustment function, it is possible to easily lower the vehicle height only when loading / unloading luggage or getting on and off passengers.
[Brief description of the drawings]
FIG. 1A is a longitudinal front view of a vehicle height adjusting device according to a first embodiment of the present invention.
(B) Another control method of the solenoid valve according to the first embodiment.
FIG. 2 is a longitudinal sectional front view of a vehicle height adjusting device according to the prior art.
[Explanation of symbols]
B Anti-rod side chamber C Rod side chamber E Accumulator oil chamber Sa Shock absorber F Reservoir 1 Pump rod 1C Control orifice 3 Cylinder 105 Outer shell 6 Piston 7 Boot 12 Piston rod 123 Opening / closing means (2-port solenoid valve)
125 Push button provided in the passenger compartment

Claims (3)

A shock absorber, an accumulator, a pump mechanism, a control orifice, and an opening / closing means;
The shock absorber is partitioned by a cylinder, an outer shell disposed outside the cylinder, a reservoir partitioned inside the outer shell, a piston rod movably inserted into the cylinder via a piston, and a piston within the cylinder. The rod side chamber and the anti-rod side chamber,
The accumulator is composed of a high pressure gas chamber, and an oil chamber communicating with the rod side chamber while being separated from the high pressure gas chamber via a boot,
The pump mechanism includes a pump rod that is inserted into the piston rod so as to be stretchable and supplies the pressure oil of the reservoir to the anti-rod side chamber and the oil chamber of the accumulator when the shock absorber is stretched.
Control orifice is formed in the pump rod the reaction rod-side chamber to control the shock absorber communicates with the reservoir at a predetermined height at a predetermined position,
The opening / closing means is a vehicle height adjustment device that communicates or shuts off the oil chamber of the accumulator with the reservoir when loading / unloading luggage and getting on / off of passengers .
The opening / closing means includes a valve seat fixed to the outer periphery of the cylinder, a high pressure port and a low pressure port formed in the valve seat, and the high pressure port and the low pressure port formed in the cylinder to connect the oil chamber of the accumulator and the above A vehicle height adjusting device comprising two communication holes communicating with the reservoir and a solenoid valve for communicating or blocking the high pressure port and the low pressure port, respectively. A cap for separating the accumulator oil chamber and the reservoir is provided between the outer shell and the cylinder, and another communication hole is formed in the cap for communicating the high-pressure port and the communication hole with the oil chamber of the accumulator. The vehicle height adjusting device according to claim 1. 3. The vehicle height adjustment according to claim 1, wherein the solenoid valve is a two-port solenoid valve controlled by a push button provided in a vehicle interior or controlled in conjunction with opening / closing of a door of a luggage compartment. apparatus.

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