JPH0637123B2 - Vehicle height adjustment device - Google Patents

Description

TECHNICAL FIELD The present invention relates to a vehicle height adjusting device for an automobile.

(Prior Art) Conventionally, in order to adjust the vehicle height of an automobile, a pump is driven to draw hydraulic oil from a tank, which is pumped to an oil passage (piping), and the oil passage is branched midway. The hydraulic oil is supplied to the front jack (shock absorber) and the rear jack via the branch oil passage to increase the vehicle height, and when lowering the vehicle height, the pump is reversed to discharge the oil branched from the middle of the oil passage. The oil passage is opened to return the hydraulic oil from the jack into the tank.

(Problems to be Solved by the Invention) In the above-described conventional vehicle height adjusting device, a problem occurs when the loaded weight increases. That is, as the loaded weight increases, the reaction force applied to the rear jack increases, the front jack expands first when the vehicle height is increased, and the rear jack contracts first when the vehicle height is decreased. As a result, the optical axis becomes upward and the oncoming vehicle is annoying at night.

(Means for Solving Problems) In order to solve the above problems, the present invention provides a differential pressure valve at a branch portion of an oil passage that connects a pump and a front jack and a rear jack, and when increasing a vehicle height, a rear valve is provided. The hydraulic oil flows to the jack first, and when lowering the vehicle height, the hydraulic oil returns first from the front jack.

(Operation) When the pump is normally rotated to increase the vehicle height, the first
Hydraulic oil enters the oil chamber of the, the spool moves and the first oil chamber communicates with the branch oil passage to the rear jack, the rear jack extends first, and then the relief valve opens and branches to the front jack. Hydraulic oil enters the oil passage and the front jack extends.

When the pump is reversed to lower the vehicle height, the hydraulic oil from the front jack first flows through the check valve to the discharge oil passage, and then due to the pressure difference between the branch oil passage to the rear jack and the second oil chamber. The spool moves, the first oil chamber communicates with the branched oil passage to the rear jack, and the hydraulic oil from the rear jack is discharged to the tank.

(Example) Below, the Example of this invention is described based on an accompanying drawing.

FIG. 1 is a schematic configuration diagram of a vehicle height adjusting device according to a first embodiment of the present invention, in which a pump (2) driven by a motor (1) capable of rotating in the normal and reverse directions is used to operate oil from a tank (3). The oil passages (4), (5) for pumping up the oil are extended, and these oil passages (4), (5) are equipped with check valves (4a), (5a) for preventing backflow to the tank (3). Line (4) pumps hydraulic oil when the pump (2) rotates forward, and oil line (5) pumps hydraulic oil when the pump (2) rotates reverse.

In addition, from the pump (2) is an oil passage that pumps hydraulic oil during normal rotation.
(6) and the oil passage (7) for pumping hydraulic oil at the time of reverse rotation are extended, the oil passage (6) is branched at the differential pressure valve (8) part, and one of the branched oil passages (9) is connected to the front jack ( 10), the other branch oil passage (11) is connected to the rear jack (12), and the branch oil passage (1
A pressure switch (13) for high pressure and a pressure switch (14) for low pressure are provided in 1).

The oil passage (7) also extends to the spool valve (15),
Discharge oil passage branched from oil passage (6) by activating (15)
The relief valve (17) provided in (16) is opened and closed.

By the way, the differential pressure valve (8) is, as shown in FIG.
Pump (2) in (18) Oil passage (6) for pumping hydraulic oil during normal rotation
, A branch oil passage (9) connected to the front jack (10) and a branch oil passage (11) connected to the rear jack (12) are respectively drilled, and the oil passage (6) and the branch oil passage (9) are separated from each other. The check valve (19) allows the flow of hydraulic oil from the passage (9) to the oil passage (6).

A cylinder portion (20) is formed in the case (18), and a spool (21) is slidably provided in the cylinder portion (20). The spool (21) divides the inside of the cylinder portion (20) into a first oil chamber (S ₁ ) and a second oil chamber (S ₂ ), and a spring (2
It is biased by 2) in the direction of closing the branch oil passage (11). The oil passage (6) opens in the first oil chamber (S ₁ ), the branch oil passage (9) opens in the second oil chamber (S ₂ ), and the spool (21) Inside the first oil chamber (S ₁ ) to the second oil chamber (S 1
A relief valve (23) that allows the flow of hydraulic oil to ₂ ) at a pressure above the set value is provided.

The operation of the vehicle height adjusting device having the above structure will be described below.

First, when increasing the vehicle height, pump the motor (1).
(2) is rotated in the normal direction, hydraulic oil is pumped from the tank (3) through the oil passage (4), and is hydraulically fed to the differential pressure regulating valve (8) through the oil passage (6). Then, the hydraulic oil enters the first oil chamber (S ₁ ) of the differential pressure valve (8), and the pressure of the first oil chamber (S ₁ ) becomes higher than that of the _second oil chamber (S ₂ ). Therefore, the spool (21) moves to the right in the figure,
The first oil chamber (S ₁ ) communicates with the branch oil passage (11), and the hydraulic oil from the oil passage (6) flows to the rear jack (12) via the branch oil passage (11) and the rear part of the vehicle body Comes up first.

Next, when a predetermined amount of hydraulic oil flows to the rear jack (12),
The pressure in the branch oil passage (11) also increases, and therefore the pressure in the first oil chamber (S ₁ ) also increases. Then, the relief valve (23) is opened and the working oil flows from the _first oil chamber (S ₁ ) to the second oil chamber (S ₂ ), and this working oil flows through the branch oil passage (9) to the front jack ( It is supplied to 10), the front part of the car body is also lifted, and the height of the whole car body is adjusted. And the front jack (1
When a certain amount of hydraulic oil is supplied to (0) as well, the pressure in the branch oil passage (11) becomes even higher, which is detected by the high pressure switch (13) and the drive of the motor (1) is stopped. , Finish adjusting the vehicle height.

On the other hand, when lowering the vehicle height, the motor (1) reverses the pump (2), pumps hydraulic oil from the tank (3) through the oil passage (5), and feeds it through the oil passage (7). Spool valve (1
5), the relief valve (17) is operated by the spool valve (15), and the discharge oil passage (16) is opened. Then, the pressure in the oil passage (6) becomes lower than the pressure in the branch oil passage (9), so the check valve (19) opens, and the hydraulic oil from the front jack (10) flows into the branch oil passage (9) and the oil. It is returned to the inside of the tank (3) through the passage (6) and the oil discharge passage (16), and the front portion of the vehicle body is lowered first.

Along with this, the pressure in the _second oil chamber (S ₂ ) becomes lower than the pressure in the branch oil passage (11), so the spool (21) is pushed to the right in the figure and moved, and the branch oil passage (11) is moved. (11) communicates with the first oil chamber (S ₁ ), and hydraulic oil from the rear jack (12) branches into the oil passage (11), the first oil chamber (S ₁ ), the oil passage (6). And it is returned to the inside of the tank (3) through the discharge oil passage (16), and the rear part of the vehicle body becomes lower. Then, if the pressure in the branch oil passage (11) becomes less than a predetermined value, this is detected by the low pressure pressure switch (14) and the motor (1) is stopped,
Complete the vehicle height adjustment.

FIG. 3 is a schematic view of the vehicle height adjusting device according to the second embodiment, and the same members as those in the first embodiment are designated by the same reference numerals.

That is, in this embodiment, the spool valve (25) capable of maintaining the open state of the discharge oil passage (16) is provided in the middle of the discharge oil passage (16) branched from the oil passage (6). . The spool valve (25) divides the inside of the case into a first oil chamber (S ₃ ) and a second oil chamber (S ₄ ) by a spool (26), and the first oil chamber (S ₃ ) is filled with oil. open branch oil passage from the road (6) (6a), a second oil chamber (S ₄₎ is an oil passage
(7) is opened, and the orifice is provided in the spool (26).
An oil passage (27) provided with (27a) (check valve) is formed, and this oil passage (27) communicates the second oil chamber (S ₄ ) with the discharge oil passage (16).

Its action Thus, during forward rotation of the pump (2) to increase the vehicle height, a first oil chamber of the spool valve via the branch oil passage (6a) (25) (S ₃₎ in the hydraulic oil Inflow, move the spool (26) to the right in the figure to close the discharge oil passage (16), and hydraulic oil is sent under pressure to the differential pressure regulating valve (8) via the oil passage (6). Similar to the example, first, hydraulic oil is supplied to the rear jack (12), then hydraulic oil is supplied to the front jack (10), and the rear portion of the vehicle body is lifted before the front portion. The hydraulic oil in the second oil chamber (S ₄ ) flows through the pump (2) into the oil passage (6) together with the hydraulic oil pumped from the tank (3).

On the other hand, when lowering the vehicle height, it is sufficient to drive the motor (1) for the first few seconds (about 3 seconds). That is, when the motor (1) is reversed for the first predetermined time, the second oil chamber (S
₄ ) Hydraulic oil is supplied inside. The orifice (27a) is provided in the oil passage (27) that connects the second oil chamber (S ₄ ) and the discharge oil passage (16).
Is formed, the pressure in the second oil chamber (S ₄ ) increases, the spool (26) moves to the left in the drawing, and the discharge oil passage (16) is opened. At this time, the hydraulic oil in the first oil chamber (S ₃ ) is the pump
(2) Flows through the inside to the oil passage (7) together with the hydraulic oil pumped from the tank (3). At this point, the timer stops the motor (1). When the discharge oil passage (16) is opened, hydraulic oil is first returned from the front jack (10) through the differential pressure valve (8) as in the first embodiment, and then hydraulic oil is returned from the rear jack (12). As it is returned, the front part of the car body goes down earlier than the rear part.

(Effects of the Invention) According to the present invention as described above, since the front portion of the vehicle body does not become higher than the rear portion during vehicle height adjustment, the optical axis of the headlight does not face upward at night, This prevents an oncoming vehicle from being annoying.

Further, with the configuration of the second embodiment, the driving time of the motor can be shortened when the vehicle height is lowered, which is advantageous in terms of power consumption, motor (pump) life, noise, and the like.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of a vehicle height adjusting device according to the present invention, and FIG.
FIG. 3 is a sectional view of a differential pressure valve, and FIG. 3 is a schematic view of a vehicle height adjusting device according to another embodiment. In the drawing, (1) is a motor, (2) is a pump, (3) is a tank, (6) is an oil passage, (8) is a differential pressure valve, (9) and (11) are branched oil passages,
(10) is front jack, (12) is rear jack, (19) is check valve, (23) is relief valve, (21) is spool, (S ₁ )
Is a first oil chamber, and (S ₂ ) is a second oil chamber.

Claims (1)

[Claims] Claims: 1. A pump for hydraulic oil in a tank is pumped up, and this hydraulic oil is supplied to a front jack and a rear jack through an oil passage and a branch oil passage connecting the pump to the front jack and the rear jack. In the vehicle height adjusting device configured to return the hydraulic oil from the inside of the tank through the oil passage and the branch oil passage, a differential pressure valve is arranged at the branch portion of the oil passage, and the differential pressure valve is provided with a pump. An oil passage communicating with the rear jack, a branch oil passage communicating with the rear jack, and a branch oil passage communicating with the front jack are bored, and the first oil chamber and the second oil chamber are provided by a spool that opens and closes the branch oil passage communicating with the rear jack. The oil chamber of
An oil passage communicating with the pump is opened in the second oil chamber, a branch oil passage communicating with the front jack is opened in the second oil chamber, and the first oil chamber and the second oil chamber are connected to each other. A relief valve that allows the flow of hydraulic oil from the first oil chamber to the second oil chamber at a pressure above a set value is used for communication, and the branch oil passage that communicates with the front jack and the oil passage that communicates with the pump are the front jack. A vehicle height adjusting device characterized in that a check valve that allows the flow of hydraulic oil from a branched oil passage communicating with the oil passage to an oil passage communicating with the pump is communicated.