JP3953567B2 - Suspension device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a suspension apparatus, and more particularly, to an improvement of a suspension apparatus set so as to enable vertical movement of a vehicle body and suppression of a roll in a traveling vehicle.
[0002]
[Prior art and its problems]
Recent suspension devices are not only proposed to support the vehicle body with respect to the axle, but are also proposed to enable the vehicle body to move up and down and to suppress the roll in a vehicle that is actively traveling by a damping action. Often.
[0003]
That is, in this type of suspension device, in many cases, a hydraulic shock absorber is provided between the vehicle body side and the axle side of the vehicle, but this is generated by a damping valve incorporated in the hydraulic shock absorber. It is proposed as a configuration in which the damping force to be changed is high or low.
[0004]
And, in order to change the damping force generated by the damping valve built in the hydraulic shock absorber, the configuration of the damping valve itself is of course complicated. Equipment such as a controller that controls the operation of the damping valve by signals from these various sensors is essential.
[0005]
As a result, in the proposal of a configuration for changing the damping force generated by the damping valve incorporated in the hydraulic shock absorber, it is impossible to reduce the cost of the suspension device, which makes it difficult to install on a popular car. Therefore, there is a risk that improvement in versatility cannot be expected.
[0006]
On the other hand, for example, in the proposal according to Japanese Patent Laid-Open No. Hei 8-132846, the damping force is not changed by a damping valve built in the hydraulic shock absorber, but is adjusted outside and communicated with the hydraulic shock absorber. As a result, the damping force acting as the pressure cylinder is changed to change the overall damping force.
[0007]
However, in the proposal disclosed in this publication, the structure of the cylinder body that constitutes the pressure regulating cylinder that is the damping portion and the structure of the free piston that is housed in the cylinder body become complicated. Aside from the equipment on high-end cars, it makes it difficult to install on popular cars, and it also makes it impossible to expect improved versatility.
[0008]
The present invention was created in view of the above-described circumstances, and the object of the present invention is to enable vertical movement and roll suppression in a running vehicle, as well as cost reduction. Thus, an object of the present invention is to provide a suspension device that can be expected to improve its versatility and is optimal for mounting on vehicles including a popular car.
[0009]
[Means for Solving the Problems]
In order to achieve the above-described object, the configuration of the present invention includes a pair of hydraulic shock absorbers disposed on the left and right sides of the vehicle, the upper end side being connected to the vehicle body side, and the lower end side being connected to the axle side, and the pair of hydraulic pressures. In a suspension device having an external damping part communicating with each piston-side oil chamber of the shock absorber and an accumulator communicated with the external damping part, the external damping part is slidable in the housing and the chamber of the housing A pair of left and right spring chambers formed on both sides of the spool, a pair of left and right centering springs disposed in each spring chamber, and a piston side oil chamber of each hydraulic shock absorber on each side of the spool. A pair of left and right oil passages communicating with the spring chamber, a left and right first oil passage branching from this oil passage and communicating each piston-side oil chamber with the accumulator, and each of the first oil passages A pair of left and right damping valves, a left and right second oil passage that branches off from the oil passage and communicates with or is blocked by the accumulator, and a left and right oil passage arranged in each of the second oil passages. A pair of spool switching control differential pressure detection orifices, and when the spool is neutral, the piston-side oil chamber of each hydraulic shock absorber is connected to the accumulator via each of the second oil passages and each differential pressure detection orifice. On the other hand, when the spool is non-neutral, the second oil passages are shut off, and the piston-side oil chambers of the hydraulic shock absorbers communicate with each other via the first oil passages and the damping valves. It is characterized by being set to .
[0010]
DETAILED DESCRIPTION OF THE INVENTION
An embodiment of the present invention will be described below with reference to the drawings.
As shown in FIG. 1, the suspension device of the present invention includes a pair of hydraulic shock absorbers 1 and 1 disposed on the left and right sides of a vehicle, the upper end side being connected to the vehicle body B side, and the lower end side being connected to the axle A side. The pair of hydraulic shock absorbers 1 and 1 includes an external damping portion 2 that communicates with the piston-side oil chambers 1 a and 1 a , and an accumulator 3 that communicates with the external damping portion 2.
As shown in FIG. 2, the external damping portion 2 includes a housing 21, a spool 23 slidably inserted into the chamber of the housing 21, and a pair of left and right spring chambers 21 a formed on both sides of the spool 23 . 21 a , a pair of left and right centering springs 22, 22 disposed in each spring chamber 21 a , 21 a , and piston side oil chambers 1 a , 1 a of each hydraulic shock absorber 1 , 1 are connected to both sides of the spool 23. Left and right oil passages 15, 15 communicating with the respective spring chambers 21 a , 21 a, and left and right oil passages 15, 15 branching from the oil passages 15, 15 to communicate the piston-side oil chambers 1 a , 1 a with the accumulator 3. The first oil passages 24, 24 and the pair of left and right damping valves 25, 25 respectively disposed in the first oil passages 24, 24, and the accumulator branching off from the oil passages 15, 15. 3 or communicated with 3 Left and right second oil passages 24b and 24b and a pair of left and right spool switching control differential pressure detection orifices 26 and 26 disposed in the second oil passages 24b and 24b, respectively. .
Furthermore, the piston-side oil chamber 1 a, 1 a is above the second oil passage 24b of each hydraulic damper 1 and 1 when the neutral spool 23, 24b and the accumulator 3 via the differential pressure orifice 26 On the other hand, when the spool 23 is non-neutral, the second oil passages 24 b and 24 b are blocked, and the piston-side oil chambers 1 a and 1 a of the hydraulic shock absorbers 1 and 1 are connected to the first oil passages 24. , 24 and the respective damping valves 25, 25 are set to communicate with each other.
[0011]
In the illustrated embodiment, a suspension spring disposed in parallel with the hydraulic shock absorber 1 between the vehicle body B side and the axle shaft A side is not shown, but this suspension spring is hydraulic. A shock absorber 1 may be interposed, and a tire T is connected to the tip of the axle A.
Explaining briefly below, first, the hydraulic shock absorber 1 can slide, for example, a piston 12 that defines a rod-side oil chamber 1b together with a piston-side oil chamber 1a in a cylinder 11 connected to the axle A side of the vehicle. The base end of the piston 12 is connected to the vehicle body B side of the vehicle, and the tip end of a piston rod 13 is inserted into the cylinder 11 so as to be able to protrude and retract.
[0012]
The piston-side oil chamber 1a in the cylinder 11 communicates with the rod-side oil chamber 1b via a damping valve 14 disposed on the piston 12, and the external damping portion 2 via an oil passage 15 disposed on the outside. It is communicated within.
[0013]
The hydraulic shock absorber 1 is naturally urged in the extending direction, that is, the piston rod 13 tends to protrude from the cylinder 11 by the urging force of the suspension spring.
[0014]
Further, in the illustrated embodiment, the piston-side oil chamber 1a is communicated with the oil passage 15 so as to penetrate the cylinder 11, but instead of this, although not shown, the piston 12 and the piston rod 13 The oil passage 15 may be communicated with a through hole formed in the shaft core portion.
[0015]
Next, as shown in FIG. 2, the external damping portion 2 is basically slidable within the housing 21 under the arrangement of a centering spring, that is, a pair of springs 22 and 22 in the illustrated embodiment. And a damping valve 25, 25 disposed in the oil passages 24, 24 for communicating each oil passage 15 and the accumulator 3, and further, sliding of the spool 23. The differential pressure detection orifices 26 and 26 for controlling the movement are provided.
[0016]
The pair of springs 22 are accommodated in spring chambers 21 a that appear as extra portions on both ends of the spool 23 by accommodating the spool 23 in a chamber (not shown) formed in the housing 21. Thus, when no external force is applied to the spool 23, the spool 23 is maintained in a neutral state by the respective spring forces, that is, normally the spring force set to be the same.
[0017]
The spring chamber 21a communicates with the oil passage 15 through an oil passage 21b opened in the housing 21 so as to communicate with the spring chamber 21a. The oil passage 21b communicates with the oil passage 24 and an oil passage 24b described later. Is also communicated.
[0018]
The spool 23 is slidably accommodated in the above-described chamber, and has two annular grooves 23a and 23b on the outer periphery, and the annular grooves 23a and 23b are oil passages 24a and 24a when neutral. And 24b, 24b, and is set to block the communication of the annular grooves 23a, 23b to the oil passages 24a, 24a and 24b, 24b during non-neutral when sliding.
[0019]
The oil passage 24a communicates with the oil passage 24 in which the damping valve 25 is disposed. At this time, the oil passage 24b communicates between the damping valve 25 and the accumulator 3, and the oil passage 24b is connected to the differential pressure detection orifice 26. As described above, the fluid is communicated with the oil passage 15 and the oil passage 24. However, at this time, the fluid is communicated between the damping valve 25 and the piston-side oil chamber 1a of the hydraulic shock absorber 1.
[0020]
The accumulator 3 has an oil chamber 3 a and a gas chamber 3 b partitioned by a bladder 32 in the tank 31, so that the gas chamber 3 b expands and contracts according to the oil pressure in the oil chamber 3 a communicating with the oil passage 24. It is configured.
[0021]
Therefore, in the suspension device according to this embodiment formed as described above, when the left and right hydraulic shock absorbers 1 and 1 are compressed in the same phase by the vertical movement of the vehicle body, for example, each piston side The hydraulic oil in the oil chamber 1a flows into each rod-side oil chamber 1b via each damping valve 14, and at this time, the pressure-side damping action by the damping valve 14 is expressed.
[0022]
On the other hand, the hydraulic oil corresponding to the intrusion volume integral of the piston rod 13 flows out from each piston-side oil chamber 1a through each oil passage 15 toward the external damping portion 2, that is, the spool 23 in the housing 21. .
[0023]
At this time, since the hydraulic oil from the left and right piston side oil chambers 1a tends to flow into the left and right spring chambers 21a at the same time, the spool 23 cannot slide in either direction and is maintained in a neutral state. Is done.
[0024]
Accordingly, the spool 23 remains in a state where the oil passage 24b and the oil passage 24a are communicated with each other through the annular grooves 23a and 23b, and the hydraulic oil from the piston-side oil chamber 1a via the oil passage 15 is transferred to the annular groove of the spool 23. It flows into the accumulator 3 through 23a, 23b. At this time, the gas chamber 3b contracts in the accumulator 3, allowing the hydraulic oil to flow into the oil chamber 3a, and the role of the reservoir chamber in the hydraulic shock absorber 1 End.
[0025]
At this time, it is possible to expect an effective air spring effect by the accumulator 3 by appropriately setting the gas pressure in the gas chamber 3b.
[0026]
Contrary to the above, during the in-phase extension stroke of each hydraulic shock absorber 1, the hydraulic oil from the rod side oil chamber 1b flows into the piston side oil chamber 1a via the damping valve 14, and at this time, the damping is performed. The extension side damping action by the valve 14 is expressed.
[0027]
On the other hand, the amount of hydraulic oil corresponding to the withdrawal volume of the piston rod 13 that is insufficient in the piston-side oil chamber 1a is replenished from the external damping part 2 side.
[0028]
That is, the hydraulic oil from the accumulator 3 is replenished to the piston-side oil chamber 1a through the path of the oil path 24a, the annular grooves 23a and 23b, and the oil path 24b, which are paths opposite to the above-described path.
[0029]
Therefore, when the left and right hydraulic shock absorbers 1 and 1 expand and contract in phase with the vertical movement of the vehicle body, predetermined damping side and compression side damping forces are generated by the damping valve 14 in each hydraulic shock absorber 1, and The air spring effect by the accumulator 3 is exhibited.
[0030]
On the other hand, when the left and right hydraulic shock absorbers 1 and 1 expand and contract in opposite phases by the roll of the vehicle body, for example, the left hydraulic shock absorber 1 in FIG. When the right hydraulic shock absorber 1 is extended, the following occurs.
[0031]
That is, in the left hydraulic shock absorber 1, an amount of hydraulic oil corresponding to the intrusion volume integral of the piston rod 13 flows out toward the external damping portion 2 via the oil passage 15 from the piston-side oil chamber 1 a. In the hydraulic shock absorber 1, an amount of hydraulic oil corresponding to the withdrawal volume of the piston rod 13 tends to flow from the external damping portion 2 into the piston-side oil chamber 1 a.
[0032]
At this time, in the left hydraulic shock absorber 1, the hydraulic oil from the piston side oil chamber 1a flows into the rod side oil chamber 1b via the damping valve 14, and in the right hydraulic shock absorber 1, the rod side oil chamber 1 The hydraulic fluid from 1b flows into the piston side oil chamber 1a through the damping valve 14, and a predetermined pressure side or extension side damping action by each damping valve 14 is expressed.
[0033]
At this time, in the external damping portion 2, the inflow and outflow of the hydraulic oil is expressed through the oil passage 21b communicating with the oil passage 15, but the differential pressure detection orifice is provided in the oil passage 24b communicating with the oil passage 21b. 26 is disposed, hydraulic oil from the oil passage 15 side flows into the left spring chamber 21a in the drawing, and hydraulic oil flows into the oil passage 15 side in the right spring chamber 21a in the drawing. Leaks.
[0034]
As a result, while the left spring chamber 21a is in a high pressure state, the right spring chamber 21a is in a low pressure state, and therefore the spool 23 slides in the right direction in the drawing.
[0035]
Therefore, the communication between the oil passage 24b and the oil passage 24a by the annular grooves 23a and 23b formed in the spool 23 is blocked, so that the hydraulic oil from the left oil passage 15 is left on the left oil passage 24, That is, the oil flows from the accumulator 3 side through the damping valve 25 and the working oil from the accumulator 3 side flows toward the right oil passage 15 through the right oil passage 24, that is, through the damping valve 25.
[0036]
As a result, the air spring effect by the accumulator 3 is not exhibited during the expansion and contraction of the opposite phase, but the damping force by the damping valve 14 is generated in each hydraulic shock absorber 1 and the damping force by the damping valve 25 in the external damping unit 2. Will be generated.
[0037]
Therefore, if the generation of the damping force during expansion / contraction of the respective hydraulic shock absorbers 1 described above is compared with the generation of damping force during expansion / contraction of the opposite phase, a higher damping force is generated during the expansion / contraction of the opposite phase. It becomes possible to suppress the roll of the vehicle body, and it becomes possible to suppress the vertical movement of the vehicle body due to the occurrence of a low damping force accompanied by the air spring effect during the expansion and contraction of the same phase.
[0038]
By suppressing the roll of the vehicle body, the steering stability in the vehicle is improved, and the riding comfort in the vehicle is improved by the generation of a low damping force accompanied by the air spring effect.
[0039]
FIG. 3 shows a specific embodiment of the external damping part 2. In the external damping part 2 of this embodiment, the housing 21 is formed in a block shape, It is assumed that the accumulator 3 is connected to the housing 21 and the hydraulic shock absorber 1 is connected via the oil passage 15.
[0040]
A housing chamber (not shown) is formed in the housing 21, and a spool 23 and a pair of springs 22 and 22 serving as centering springs are accommodated in the chamber.
[0041]
In this embodiment as well, the basic configuration is the same as that of the embodiment shown in FIG. 2 described above. Detailed description will be omitted only by assigning the same reference numerals.
[0042]
Therefore, in the case of this embodiment, the housing 21 for accommodating the spool 23 in the housing 21 formed in a block shape, and the spring chamber 21a for accommodating the pair of springs 22 and 22 serving as centering springs, Furthermore, a predetermined external damping portion 2 is formed by drilling the oil passages 21b, 24, 24a, 24b that allow the spring chamber 21a and the chamber to communicate with the accumulator 3 and the hydraulic shock absorbers 1. It becomes possible to do.
[0043]
As a result, as long as the slidability of the spool 23 in the chamber is ensured, high processing accuracy is not required, so-called labor and time are not required for processing, and productivity can be improved. .
[0044]
FIG. 4 shows an external attenuator 2 according to another embodiment, but the basic configuration of the external attenuator 2 is the same as that of the embodiment shown in FIG. It is the same.
[0045]
However, this embodiment is characterized in that the centering spring that realizes the neutral state of the spool 23 is composed of one spring 27. As a result, as in the above-described embodiment, the spring 22 is attached. The plug 28 (see FIG. 3) for correcting the variation in power is not required, the number of parts is reduced, and the influence of variation in the biasing force of the spring 27 is not affected. This is advantageous in that the size of the housing 21 can be reduced.
The plug 28 is advantageously equipped.
[0046]
【The invention's effect】
As described above, in the present invention, the housing and the spring chamber for accommodating the spool and the centering spring are mainly housed in the housing, and further, the chamber and the spring chamber are connected to the accumulator and each hydraulic shock absorber. Since the predetermined external damping portion can be formed by the work of drilling each enabling oil passage, high machining accuracy is not required as long as the slidability of the spool in the chamber is ensured. Thus, so-called labor and time are not required for processing, and the productivity can be improved, thereby reducing the cost of the entire suspension device.
[0047]
As a result, according to the present invention, it is possible to reduce the cost and improve the versatility, as well as to suppress the vertical movement and roll in the traveling vehicle. There is an advantage that is most suitable for equipment including vehicles.
Furthermore. In the present invention, since the differential pressure control orifices 26 and 26 for switching and controlling the spool are provided, when each of the hydraulic shock absorbers 1 and 1 expands and contracts in the opposite phase by the roll of the vehicle body B, the spool 23 slides in one direction. Since the second oil passages 24b and 24b are shut off and the damping force by the damping valves 25 and 25 is generated in the respective hydraulic shock absorbers 1 and 1, rolls of the vehicle body can be suppressed.
[Brief description of the drawings]
FIG. 1 is a schematic diagram showing a vehicle equipped with a suspension device of the present invention.
FIG. 2 is a schematic view showing a suspension device according to an embodiment of the present invention.
FIG. 3 is a cross-sectional view showing an embodiment of an external attenuation unit.
FIG. 4 is a cross-sectional view showing another embodiment of the external attenuation unit.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Hydraulic buffer 1a Piston side oil chamber 2 External damping part 3 Accumulator 21 Housing 22 A pair of springs 23 which comprise a centering spring Spool 24 Oil path 25 Damping valve A Axle B Car body

Claims (1)

A pair of hydraulic shock absorbers disposed on the left and right sides of the vehicle, the upper end side being connected to the vehicle body side and the lower end side being connected to the axle side, and an external damping portion communicating with each piston-side oil chamber of the pair of hydraulic shock absorbers In the suspension device having the accumulator communicated with the external damping part, the external damping part includes a housing, a spool that is slidably inserted into the chamber of the housing, and a pair of left and right formed on both sides of the spool. Spring chambers, a pair of left and right centering springs disposed in each spring chamber, a pair of left and right oil passages communicating the piston side oil chamber of each hydraulic shock absorber with each spring chamber on both sides of the spool, and the oil passage And a pair of left and right damping valves respectively disposed in each of the first oil passages, and the oil passages. Left and right second oil passages branched from and connected to the accumulator, and a pair of left and right spool switching control differential pressure detection orifices respectively disposed in the second oil passages. When the spool is neutral, the piston-side oil chamber of each hydraulic shock absorber communicates with the accumulator via the second oil passages and the differential pressure detection orifices . The suspension device is configured such that the oil passages are blocked and the piston-side oil chambers of the respective hydraulic shock absorbers are communicated with each other via the respective first oil passages and the respective damping valves.

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