JPH0672127A - Suspension system for four wheel vehicle - Google Patents

Abstract

PURPOSE:To facilitate the setting of a suspension system by attaching at least two hydraulic cylinders for four wheels to compose integrally free pistons in respective pressure adjusting cylinders provided in every oil pressure path so as to be interlocked with each other and affording communication between the oil pressure paths through a throttle member. CONSTITUTION:Hydraulic cylinders 2 interposed between the car body side and the wheel side are provided left and right of the car body, and the upper oil chambers 7 of the respective hydraulic cylinders 2 are interlocked with the oil chamber 14 of a pressure adjusting cylinder 11a so that free pistons 12 in every pressure adjusting cylinder are interlocked with each other and a throttle member 4 is interposed between oil pressure paths 16, 17 in every hydraulic cylinder 2. Oil amount passing through the throttle 4 of the piston is small when the hydraulic cylinders 2 are extended and contracted in the same direction, and the operation of the hydraulic cylinders 2 is damped by the oil passing through throttles 9 of piston, when operated in the different directions, the throttle member 4 causes the damping effect. The setting of the suspension system is facilitated since requirements for using the respective throttle can be limited.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention is used in automobiles and the like.
The present invention relates to a suspension system for a wheeled vehicle.

[0002]

2. Description of the Related Art Conventionally, as a suspension device for suppressing rolling of a vehicle body in a four-wheeled vehicle, for example, JP-A-63-22
There is one disclosed in Japanese Patent No. 2914.

The suspension device disclosed in this publication has hydraulic cylinders interposed between the left and right wheel sides and the vehicle body side,
The oil chamber of the left hydraulic cylinder and the oil chamber of the right hydraulic cylinder are made to communicate with each other via a communication pipe. The piston of each hydraulic cylinder was provided with a throttle so that the oil chambers on both sides of the piston were connected to each other.

The communication pipe connects the upper oil chamber of the left hydraulic cylinder (the oil chamber closer to the vehicle body than the piston) and the lower oil chamber of the right hydraulic cylinder (the oil chamber closer to the wheel than the piston) to the left hydraulic chamber. Two cylinders are provided to connect the lower oil chamber of the cylinder and the upper oil chamber of the right hydraulic cylinder, and a throttle is provided in each of the communication pipes.

That is, when the vehicle body is tilted and one of the left and right hydraulic cylinders is contracted, oil is pumped from the lower oil chamber of the contracted hydraulic cylinder to the upper oil chamber of the other hydraulic cylinder, and at the same time, the other hydraulic cylinder is contracted. Oil is pumped from the lower oil chamber of the hydraulic cylinder to the upper oil chamber of the hydraulic cylinder that contracts, which eventually causes both hydraulic cylinders to contract and the leaning of the vehicle body is suppressed. Then, the rolling action is attenuated by the oil passing through the throttle of the communication pipe.

[0006]

However, in the suspension configured as described above, in setting the damping performance, the damping performance at the throttle of the piston of each hydraulic cylinder and the damping performance at the throttle provided in each communicating pipe are set. It must be done in consideration of damping performance. Therefore, the setting was extremely complicated.

Further, there is a problem in that the communication pipes are connected to the upper and lower oil chambers of each hydraulic cylinder, and the piping becomes complicated.

[0008]

A suspension system for a four-wheeled vehicle according to a first aspect of the present invention defines an inside of a cylinder into an upper oil chamber and a lower oil chamber by a piston with a throttle, and a wheel side and a vehicle body side. It has a hydraulic cylinder that is connected between the wheel side and the vehicle body side, with a cylinder body connected to one side and a piston connected to the other side, and an oil chamber that communicates with one of the upper and lower oil chambers of this hydraulic cylinder. The oil chamber and the high pressure gas chamber are provided with a pressure adjusting cylinder defined by a free piston, and the hydraulic cylinder is mounted on at least two of the four wheels, and the adjusting valve is provided for each hydraulic path of the hydraulic cylinder. A pressure cylinder is provided, and the free pistons of the pressure regulating cylinders are integrally configured to interlock with each other, and the hydraulic paths are communicated with each other via a throttle member.

In the suspension system for a four-wheel vehicle according to the second aspect of the invention, the inside of the cylinder is divided into an upper oil chamber and a lower oil chamber by a piston with a throttle, and the cylinder body is provided on one of the wheel side and the vehicle body side. It has a hydraulic cylinder connected between the wheel side and the vehicle body side with a piston connected to the other side, and an oil chamber communicating with one of the upper and lower oil chambers of this hydraulic cylinder. A gas chamber and a pressure regulating cylinder defined by a free piston, 4
At least two of the wheels are equipped with the hydraulic cylinders, the pressure regulating cylinders are provided for each hydraulic path of the hydraulic cylinders, and the free pistons of the respective pressure regulating cylinders are integrally configured to interlock with each other. A second pressure regulating cylinder, in which an oil chamber and a high-pressure gas chamber are defined by a free piston, is connected to the hydraulic path via an inflow path and an outflow path on the oil chamber side, and is restricted to the inflow path and the outflow path. Are installed respectively.

In the suspension system for a four-wheel vehicle according to the third aspect of the invention, the inside of the cylinder is divided into an upper oil chamber and a lower oil chamber by a piston with a throttle, and the cylinder body is provided on one of the wheel side and the vehicle body side. It has a hydraulic cylinder connected between the wheel side and the vehicle body side with a piston connected to the other side, and an oil chamber communicating with one of the upper and lower oil chambers of this hydraulic cylinder. A gas chamber and a pressure regulating cylinder defined by a free piston, 4
At least two of the wheels are equipped with the hydraulic cylinders, the pressure regulating cylinders are provided for each hydraulic path of the hydraulic cylinders, and the free pistons of the respective pressure regulating cylinders are integrally configured to interlock with each other. A main free piston that interlocks a free piston of one of the pressure adjusting cylinders with a free piston of the other pressure adjusting cylinder, and a main free piston movably provided with respect to the main free piston. It is formed by a sub free piston that forms a sub oil chamber between the high pressure gas chamber and the high pressure gas chamber, and the sub oil chamber is connected to the hydraulic path via a throttle member provided in the main free piston.

[0011]

When the two hydraulic cylinders expand and contract in the same direction, a small amount of oil passes through the throttle of the pressure regulating cylinder, and the operation of the hydraulic cylinder is attenuated by the oil passing through the throttle of the piston of the hydraulic cylinder. If both hydraulic cylinders expand or contract in different directions, a large amount of oil will flow to the throttle member on the pressure regulating cylinder side.At that time, the throttle of the piston of the hydraulic cylinder and the throttle member on the pressure regulating cylinder side should be connected. The movement of the hydraulic cylinder is dampened by the passage of oil. Therefore, when there is a difference in the operating directions of the two hydraulic cylinders, the throttle member on the pressure adjusting cylinder side exerts a damping effect.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the first invention will be described in detail below with reference to FIGS. FIG. 1 shows the fourth aspect of the first invention.
FIG. 2 is a schematic configuration diagram of a suspension device for a wheeled vehicle, FIG. 2 is a front view of the suspension device for a four-wheeled vehicle according to the first aspect of the invention, and FIG. 3 is a sectional view showing a pressure adjusting device and a throttle in an enlarged manner.

In these figures, 1 is 4 according to the present invention.
The suspension system for a wheeled vehicle is shown as the suspension system 1 mounted on the front wheel side, for example. 1 and 2, other suspension device constituent members such as a link mechanism and a cushion spring that support the front wheel to move up and down are omitted.

First, a schematic structure of a suspension system for a four-wheel vehicle according to the first invention will be described with reference to FIG. In FIG. 1, reference numeral 1 is a suspension system for a four-wheeled vehicle according to the present invention.
It is composed of left and right hydraulic cylinders 2, 2 and a pressure adjusting device 3, a throttle member 4, etc. connected to these left and right hydraulic cylinders 2, 2.

The left and right hydraulic cylinders 2, 2 have the same structure, and the inside of the cylinder body 5 filled with oil is divided by a piston 6 into an upper oil chamber 7 and a lower oil chamber 8. Further, the piston 6 has an upper oil chamber 7
And a lower oil chamber 8 are provided with a communication passage 6a, and a throttle 9 is provided in the communication passage 6a.

The hydraulic cylinder 2 connects the cylinder body 5 to the vehicle body (not shown) of the automobile, and the lower end portion of the piston rod 10 moves up and down with respect to the vehicle body together with front wheels such as front wheel suspension links. It is pivotally supported and is interposed between the vehicle body side and the front wheel side. It should be noted that the mounting direction of the hydraulic cylinder 2 can be reversed upside down from the case described above. In the present embodiment, an example is shown in which the hydraulic cylinder 2 located on the left side in FIG. 1 is mounted on the left front wheel side, and the hydraulic cylinder 2 located on the right side in FIG. 1 is mounted on the right front wheel side.

In the pressure adjusting device 3, pressure adjusting cylinders 11a are formed side by side in the cylinder body 11 with their axial directions parallel to each other, and a free piston 12 is movably fitted in each pressure adjusting cylinder 11a. And free piston 1
One of the cylinder internal spaces partitioned by 2 is filled with high pressure gas to form a high pressure gas chamber 13, and the other cylinder internal space is filled with oil to form an oil chamber 14. Two oil chambers 14 are provided because the two pressure adjusting cylinders 11a are provided.

Further, the two free pistons 12, 12 are connected to each other via a connecting member 15, and are configured to move in the same direction at the same time and interlock with each other.

As described above, two oil chambers 1 are provided.
One of 4, 4 communicates with the upper oil chamber 7 of the left hydraulic cylinder 2 through the left hydraulic passage 16, and the other communicates with the upper oil chamber 7 of the right hydraulic cylinder 2 through the right hydraulic passage 17. . That is, the pressure adjusting cylinder 11a is provided for each hydraulic path of the hydraulic cylinder 2.

The throttle member 4 is interposed between the left and right hydraulic paths 16 and 17 which connect the respective oil chambers 14 to the left and right hydraulic cylinders 2 and 2.

When the suspension device 1 having the above-described structure is mounted on the vehicle body of an automobile, each member is formed as shown in FIGS. 2 and 3. 2 and 3, the same or similar members as those described in FIG. 1 are designated by the same reference numerals and detailed description thereof will be omitted.

The hydraulic cylinder 2 shown in FIG. 2 is formed by inserting the lower portion of the cylinder body 5 into the outer cylinder 5a. The piston rod 10 is fixed to the outer cylinder 5a, and the outer cylinder 5a is configured to be pivotally supported at a portion that moves up and down together with the front wheel. The throttle 9 of the piston 6 of the hydraulic cylinder 2 has a conventionally known structure in which the opening of the communication passage 6a is closed by a leaf spring type check valve. In FIG. 2, the positions of the piston and the upper end of the outer cylinder when the hydraulic cylinder 2 is contracted most are shown by a chain double-dashed line A. FIG. 2 shows the hydraulic cylinder 2 in the most extended state.

As shown in FIG. 3, the pressure adjusting device 3 is formed by arranging pressure adjusting cylinders 11a on a cylinder body 11, and each of the pressure adjusting cylinders 11a has a substantially bottomed cylindrical free piston 12.
Are respectively inserted and formed. The free pistons 12 and 12 are connected to each other via shafts 12 a that are integrally provided in a bottomed tubular portion. Then, oil is filled into the inner space of the free piston 12 formed in the shape of a bottomed cylinder and the space surrounded by the free piston 12 and the cylinder body 11, and the free piston 12 in the cylinder body 11 is The space on the side of the shaft portion 12a is filled with high-pressure gas.

A guide rod 18 is screwed to the center of the connecting member 15, and is guided movably in the cylinder axis direction with respect to the cylinder body 11 via the guide rod 18. Reference numeral 19 is a guide member for slidably supporting the tip of the guide rod 18, and this guide member 19 has a rod guide 19a through which the guide rod 18 penetrates, and is fixed by being pressed into the bottom member 11b of the cylinder body 11. There is.

In FIG. 3, 20 is an O-ring mounted on the outer peripheral portion of the free piston 12, and 21 is the same piston ring. Reference numeral 22 is a nipple for connecting a communication pipe (not shown) to the cylinder body 11. Further, the positions of the free piston 12 and the connecting member 15 when the volume of the oil chamber 14 becomes the maximum are shown by the chain double-dashed line B in FIG.

The throttle member 4 is formed by screwing a valve support member 24 to a cylindrical case 23 having a bottom so as to close the opening. A throttle main body 25 that faces the inside of the case 23 and defines the inside of the case 23 into A and B chambers is attached to the valve support member 24, and two nipples 26 to which a communication pipe (not shown) is connected are attached. . The chamber A is a space on the bottom side of the case 23 with respect to the throttle body 25, and the chamber B is with respect to the valve support member 2 from the throttle body 25.
The space on the 4th side.

Further, the valve support member 24 is formed with communication passages 24a and 24b for communicating the oil passage in the nipple 26 with the chamber B in the case 23. With this configuration, both nipples 26
The internal oil passages are communicated with each other through the communication passage 24a, the B chamber, and the communication passage 24b.

The throttle body 25 is formed with small holes 25a and 25b penetrating the diaphragm body 25, and a check valve 27 made of a leaf spring for closing an opening of the small hole 25a on the B chamber side, and a small hole. A check valve 28 made of a leaf spring for closing the opening on the side of the chamber A of 25b is provided.

In the throttle member 4 thus constructed, when the hydraulic pressure in the chamber A of the case 23 becomes higher than that in the chamber B, the hydraulic pressure is applied to the check valve 27 through the small hole 25a to open the check valve 27. , The oil flows from the chamber A into the chamber B through the small holes 25a. On the contrary, when the hydraulic pressure in the B chamber becomes higher than that in the A chamber, the check valve 28 is opened by the hydraulic pressure and the oil flows from the B chamber to the A chamber. That is, the throttle member 4 has a two-handed structure in which resistance is generated when the check valve 27 or the check valve 28 is opened and the oil flows between the A chamber and the B chamber.

Incidentally, 29 is a nipple for connecting a communication pipe (not shown) to the bottom of the case 23, and 30 is a throttle body 25.
An adjusting screw 31 for finely adjusting the throttle amount at 31 and an O-ring 31 provided between the case 23 and the valve support member 24.

The pressure regulating device 3 and the throttle member 4 configured as described above are connected to the left and right hydraulic cylinders as shown in FIG. That is, the upper oil chamber 7 of the left hydraulic cylinder 2 communicates with one nipple 22 of the pressure regulating cylinder 4 via a communication pipe (not shown) and also communicates with the nipple 29 on the case 23 side of the throttle member 4. The upper oil chamber 7 of the right hydraulic cylinder 2 is communicated with one of the two nipples 26, 26 on the valve support member 24 side of the throttle member 4. The other of these nipples 26, 26 is communicated with the remaining nipple 22 of the pressure regulator 3.

By connecting in this manner, the left and right hydraulic paths 16, 1 connected to the left and right hydraulic cylinders 2, 2 are connected.
7 are respectively connected to the pressure regulating cylinder 11a, and
The throttle member 4 is interposed between the left and right hydraulic paths 16 and 17. The left hydraulic passage 16 communicates with the A chamber in the throttle member 4, and the right hydraulic passage 17 communicates with the B chamber.

Next, the operation of the suspension device 1 thus constructed will be described. For example, when the left and right front wheels pass over a protrusion on the road and the left and right hydraulic cylinders 2 and 2 contract, oil flows out to the hydraulic paths 16 and 17 by the amount of the piston rod 10 inserted into the cylinder body 5. . Then, the oil flows into the oil chamber 14 of the pressure regulator 3 by a flow rate corresponding to the oil outflow. At this time, assuming that the hydraulic pressures in the hydraulic paths 16 and 17 are substantially equal, there is no pressure difference between the A chamber and the B chamber in the throttle member 4, and oil does not pass through the throttle body 25. Substantially all of the corresponding oil flows into the pressure regulator 3.

The free piston 1 of the pressure regulator 3
2 and 12 move in the cylinder body 11 so that the high pressure gas is compressed by the hydraulic pressure applied from the nipple 22 side.

That is, when pitching or bouncing occurs in the vehicle body and the left and right hydraulic cylinders 2 expand and contract in the same direction, vibrations of the vehicle body are damped mainly by resistance generated when oil passes through the throttle 9 in the hydraulic cylinder 2. To be done.

When the left hydraulic cylinder 2 contracts and the right hydraulic cylinder 2 extends by turning the vehicle body to the right, the left hydraulic cylinder 2 causes oil to flow into the left hydraulic passage 16 as in the case described above. On the contrary, the right hydraulic cylinder 2 allows oil to flow in from the right hydraulic passage 17. The direction of oil flow at this time is indicated by an arrow in FIG.

In this case, the hydraulic pressure in the left hydraulic passage 16 becomes larger than the hydraulic pressure in the right hydraulic passage 17, so that the oil flows from the A chamber to the B chamber through the throttle body 25 of the throttle member 4, and the left side More than half of the oil outflow amount in the hydraulic cylinder 2 flows into the right hydraulic path 17 through the throttle member 4. Then, the left hydraulic path 16
The oil that flows from the right side hydraulic path 17 into the throttle member 4
The valve support member 24 distributes the pressure regulator 3 side and the right hydraulic cylinder 2 side. At this time, the free piston 12 of the pressure regulator 3 moves inside the cylinder body 11 according to the amount of oil flowing from the nipple 22.

That is, when the left and right hydraulic cylinders 2, 2 expand and contract in different directions due to rolling of the vehicle body, the resistance generated when oil passes through the throttle 9 in the hydraulic cylinder 2 and the throttle body of the throttle member 4. The vibration of the vehicle body is damped by the resistance generated when the oil passes through 25.

Therefore, according to the suspension apparatus 1 thus constructed, when the left and right hydraulic cylinders 2, 2 operate in the same direction, less oil passes through the throttle main body 25 of the throttle member 4, and the hydraulic cylinder 2's The operation is the piston 6
It is damped by the resistance generated by the oil passing through the throttle 9. If both hydraulic cylinders 2 and 2 operate in different directions, a large amount of oil will flow into the throttle body 25 of the throttle member 4, so at that time the hydraulic cylinder 2
The operation of the hydraulic cylinder 2 is damped by the resistance generated by the oil passing through the throttle 9 of the piston 6 and the throttle body 25 of the throttle member 4. For this reason, the damping effect becomes large when a difference occurs in the operating directions of the two hydraulic cylinders 2, 2.

In this embodiment, the pressure regulating device 3 and the throttle member 4 are communicated with the upper oil chambers 7 of the left and right hydraulic cylinders 2 and 2. However, as shown by the chain double-dashed line C in FIG. It is also possible to connect each member to the lower oil chamber 8. Even in this case, the same effect as that of the present embodiment can be obtained.

Further, the pressure adjusting device 3 may be configured as shown in FIGS. 4 to 7 in addition to the structure shown in FIGS. 2 and 3.

FIG. 4 is a front view of a suspension system using a pressure regulator having a structure having one free piston, FIG. 5 is a sectional view showing a pressure regulator having a structure having one free piston, and FIG.
7 is a front view of a suspension device using a pressure regulator having a structure in which two opposing free pistons are connected by a link, FIG.
FIG. 3 is a cross-sectional view showing a pressure regulator having a structure in which two opposing free pistons are linked by a link. In these figures, the same or equivalent members as those described in FIGS. 1 to 3 are designated by the same reference numerals, and detailed description thereof will be omitted.

In the pressure regulator 3 shown in FIGS. 4 and 5, a bottom member 11b for closing the opening of the cylinder body 11 is formed in a cylindrical shape with a bottom, and the free piston 12 is provided inside the bottom member 11b. Has been inserted. Also, this bottom member 11
In b, a thin portion 11c is formed at the tip portion so as to reduce the outer diameter, and the bottom member 11b is attached to the cylinder body 11b.
Attached to the inner peripheral surface of the cylinder body 11 and the thin portion 1
The oil chamber 14 is formed between the oil chamber 14 and the 1c. The oil chamber 14 is provided between the inner bottom surface of the bottom member 11b and the free piston 12 in addition to being provided on the cylinder side portion described above.

The free piston 12 is formed in a bottomed cylindrical shape consisting of a small diameter portion fitted into the inner peripheral portion of the bottom member 11b and a large diameter portion fitted into the inner peripheral portion of the cylinder body 11. The outer diameter of the small diameter portion and the outer diameter of the large diameter portion are
Each oil chamber 1 when this free piston 12 moves
The volume increase and the volume decrease at 4 and 14 are set to be equal. The position of the free piston 12 when the volume of the oil chamber 14 becomes the maximum is shown by the chain double-dashed line D in FIG.
Indicated by.

Of the two nipples 22, the one that communicates with the nipple 26 of the throttle member 4 is attached to the bottom of the bottom member 11b, and the one that communicates with the left hydraulic cylinder 2 is the cylinder side. It is attached to a portion of the portion corresponding to the oil chamber 14.

In the pressure regulator 3 thus constructed, the hydraulic pressure in the left hydraulic passage 16 acts on the large diameter portion of the free piston 12 via the oil chamber 14 on the cylinder side, and the hydraulic pressure in the right hydraulic passage 17 changes. Oil chamber 14 on the bottom side of the bottom member 11b
It acts on the small diameter part of the free piston 12 via the. That is, the bottom member 11b into which the small diameter portion of the free piston 12 is inserted and the cylinder body 11 into which the large diameter portion of the free piston 12 is inserted form a pressure adjusting cylinder for each hydraulic path.

Since the two oil chambers 14, 14 have a relationship in which the free piston 12 constitutes a part of the wall surface, the volume change amount in each oil chamber 14 is always equal.

In the pressure regulator 3 shown in FIGS. 6 and 7, the cylinder body 11 is formed in a substantially box shape, and the free pistons 12 are arranged on the two side portions facing each other. Both free pistons 12 are movably fitted and inserted in a bottomed cylindrical bottom member 11b screwed to the cylinder body 11 and arranged on the same axis. The free pistons 12, 12 are connected to each other via a link member 32. The link member 32 includes a first link 32a rotatably supported by the cylinder body 11,
The rotating end of the first link 32a and the free piston 12
And a second link 32b that connects to each other.

The oil chamber 14 of the pressure adjusting device 3 is formed between the inner bottom surface of the bottom member 11b and the free piston 12, and each oil chamber 14 has a left hydraulic path 16 and a right hydraulic path via the nipple 22. 17 are in communication with each other. The positions of the free piston 12 and the link member 32 when the volume of the oil chamber 14 becomes the maximum are shown by the chain double-dashed line E in FIG. 7. That is, in the pressure adjusting device 3, the pressure adjusting cylinder 11 for each hydraulic path is formed by the inner peripheral portion of the bottom member 11b.
a will be constructed.

When the two free pistons 12 are connected to each other via the link member 32 in this way, when one free piston 12 moves toward the center of the cylinder body 11 from the state shown in FIG. 12
Also moves toward the center of the cylinder body 11. Therefore, like the pressure regulator 3 shown in FIG.
The volumes of the two oil chambers 14, 14 are always the same.

In suspending the wheels by the suspension system according to the present invention, the form thereof can be appropriately changed as shown in FIGS. In these figures, the same or equivalent members as those described in FIGS. 1 to 7 are designated by the same reference numerals and detailed description thereof will be omitted. FIG. 8 shows an example in which the left and right front wheels are suspended as shown in FIGS. 1 to 7, FIG. 9 shows an example in which the left and right rear wheels are suspended, and FIG. An example in which the left and right rear wheels are suspended is shown. With the configuration shown in FIGS. 8 to 10, rolling of the vehicle body can be suppressed.

FIG. 11 shows an example in which the left front wheel is suspended and the right front wheel is suspended. With this structure, pitching of the vehicle body can be suppressed.

FIG. 12 shows an example in which the left front wheel and the right rear wheel are suspended, and the right front wheel and the left rear wheel are suspended. With this configuration, it is possible to suppress pitching and rolling, and it is also possible to suppress behavior of the vehicle body that is a combination of pitching and rolling.

In FIG. 13, one pressure regulating device is used, one hydraulic pressure regulating cylinder is connected to the hydraulic paths of the hydraulic cylinders on the left front wheel side and the left rear wheel side, and the other pressure regulating cylinder is connected to the right front wheel side. An example in which the hydraulic paths of the hydraulic cylinders on the right rear wheel side are made to communicate with each other will be shown. According to this structure, the rolling can be suppressed, and the damping force can be made difficult to act when the front wheels and the rear wheels operate so as to twist in the left and right directions when viewed from the front of the vehicle body. . That is, for example, the impact transmitted to the vehicle body when the left front wheel gets over the protrusion on the road can be small.

In FIG. 14, one pressure regulating device is used, one hydraulic pressure regulating cylinder is connected to the hydraulic passages of the left front wheel side hydraulic cylinder and the right rear wheel hydraulic cylinder, and the other pressure regulating cylinder is connected to the right front wheel hydraulic pressure. An example in which the hydraulic paths of the cylinder and the hydraulic cylinder on the left rear wheel side are communicated will be shown. According to this structure, a large damping force is exerted when the front wheels and the rear wheels are twisted in the left-right direction when viewed from the front of the vehicle body.

FIG. 15 shows an example in which the same number of pressure adjusting cylinders as the hydraulic cylinders for each wheel are provided, and the hydraulic paths of the respective hydraulic cylinders are connected to separate pressure adjusting cylinders. According to this structure, pitching and rolling can be suppressed, and it is difficult for the damping force to act when the front wheels and the rear wheels are twisted in the left-right direction when viewed from the front of the vehicle body. You can

Next, a suspension system for a four-wheeled vehicle according to the second invention will be described in detail with reference to FIGS. 16 to 19. FIG.
Is a schematic configuration diagram of a suspension system for a four-wheel vehicle according to the second invention, FIG. 17 is a front view of the suspension system for a four-wheel vehicle according to the second invention, and FIG. 18 is an enlarged view of a second pressure regulating cylinder. Sectional view, FIG.
FIG. 6 is a diagram for explaining the operation of the suspension system for a four-wheeled vehicle according to the second invention. In these figures, the same or equivalent members as those described in FIGS. 1 to 15 are designated by the same reference numerals and detailed description thereof will be omitted.

16 to 19, reference numeral 41 denotes a suspension device according to the second invention, and this suspension device 41 is mounted on the front wheel side, for example. 16 and 17
In the above, other suspension system constituent members such as a link mechanism for supporting the front wheels so as to be vertically movable and a cushion spring are omitted. Also,
This suspension device 41 is the same as the first suspension device except that the diaphragm member 4 shown in FIGS. 1 to 15 is replaced with a diaphragm member 42 described later.
It is constructed in the same manner as the suspension device 1 of the invention. In the left and right hydraulic cylinders 2 shown in FIG. 16, a ball check valve 9a is provided in the communication passage 6a, and the throttle portion including the communication passage 6a, the ball check valve 9a and the throttle 9 is a piston. No. 6 is provided at two locations with different oil flow directions.

In the throttle member indicated by reference numeral 42 in FIGS. 16 to 18, the oil chamber and the high-pressure gas chamber are free pistons 4.
3 is provided, and the oil chamber of the second pressure regulating cylinder 44 is defined by the left hydraulic passage 16
Also, it is configured to communicate with the right hydraulic path 17.
Reference numeral 45 is an oil chamber of the second pressure regulating cylinder 44, and 46 is a high pressure gas chamber.

Further, the structure of the portion that communicates the second pressure adjusting cylinder 44 with the left and right hydraulic paths 16, 17 is such that the left hydraulic path 16 and the right hydraulic path 17 are connected to the oil branch path 4.
7 and 48 are branched, and respective oil branch paths 47 and 4
The end of 8 is connected to the inflow passages 47a, 4 provided with a check valve and a throttle.
8a and the outflow passages 47b, 48b through the oil chamber 4
It has a structure to communicate with 5. The check valves of the inflow paths 47a and 48a flow only in the direction in which oil flows into the oil chamber 45, and the check valves in the outflow paths 47b and 48b flow only in the direction of oil outflow from the oil chamber 45. Is configured.

When the suspension device 41 having the above-described structure is mounted on the vehicle body of an automobile, each member is formed as shown in FIGS. 17 and 18. 17 and 1
The throttle member 42 shown in FIG. 8 is configured by disposing the second pressure adjusting cylinder 44 at one end of the valve body 49 and disposing the oil passage forming members 50, 51 at the other end. The oil passage forming member 50 communicates with the left hydraulic passage 16 through the nipple 52 and the branch pipe 53,
The oil passage forming member 51 communicates with the right hydraulic path 17 via the nipple 54 and the branch pipe 55.

The valve body 49 is formed into a substantially bifurcated cross section, and the second pressure regulating cylinder 4 is formed at a portion where the bifurcated portions gather.
4 is provided, and the oil passage forming member 5 is provided on one of the bifurcated portions.
0 is arranged and the oil passage forming member 51 is arranged on the other side.

The second pressure regulating cylinder 44 includes a cylinder body 44a having a bottomed cylindrical shape whose opening side is screwed to a valve body 49, and a free piston 43 and the like which is movably fitted in the cylinder body 47. Are formed from. One of the cylinder inner spaces defined by the free piston 43 is filled with high pressure gas to form a high pressure gas chamber 46, and the other cylinder inner space is filled with oil to form an oil chamber 45. High-pressure gas chamber 46 is free piston 4
3 from the bottom of the cylinder body 44a, the oil chamber 4
5 is closer to the valve body 49 than the free piston 43.

The reference numeral 44b provided at the bottom of the cylinder body 44a is a gas injection needle (not shown) for injecting a high pressure gas (for example, an inert gas such as nitrogen gas) into the high pressure gas chamber 46. It is a rubber material for piercing. That is, the screw 44c screwed to the bottom side of the cylinder body 44a is removed, and the rubber material 44b is inserted through the screw hole.
Insert the injection needle from outside the cylinder into the rubber material 44b
The cylinder body 44a is filled with high-pressure gas with the injection needle penetrating through.

The oil passage forming members 50 and 51 have the same structure, and have a bottomed cylindrical case 56 whose opening side is screwed to the valve body 49, and one end portion inside the case 56. The inside of the case 56 is divided into C and D2 chambers, and the other end is formed by the throttle main body 57 screwed to the valve body 49. The C
The chamber refers to a space on the valve body 49 side of the throttle body 57, and the chamber D refers to a space on the bottom side of the case 56 with respect to the throttle body 57. The nipples 52 and 54 are screwed to the bottom of the case 56. The C chamber is communicated with the oil chamber 45 of the second pressure regulating cylinder 44 via communication passages 58 and 59 that are formed so as to penetrate the valve body 49. The communication passage 58 connects the C chamber of the oil passage forming member 50 to the oil chamber 45, and
Communicates the C chamber of the oil passage forming member 51 with the oil chamber 45.

The diaphragm body 57 is formed with small holes 57a and 57b penetrating the diaphragm body 57, and a check valve 60 made of a leaf spring for closing the opening of the small hole 57a on the C chamber side, and a small hole. 57b and a check valve 61 made of a leaf spring for closing the opening on the D chamber side. That is, when the hydraulic pressure in the D chamber of the case 56 becomes higher than that in the C chamber, the hydraulic pressure is applied to the check valve 60 through the small hole 57a to open the check valve 60, and the oil passes from the D chamber through the small hole 57a. It begins to flow into room C. Conversely, when the hydraulic pressure in the C chamber becomes higher than that in the D chamber, the check valve 61 is opened by the hydraulic pressure and the oil flows from the C chamber to the D chamber. That is, the throttle body 57 has a ambidextrous structure in which resistance is generated when the oil flows between the C chamber and the D chamber by opening the check valve 60 or the check valve 61.

Reference numeral 63 designates a case as an adjusting screw for finely adjusting the diaphragm amount in the diaphragm body 57. The adjusting screw 63 has a structure in which the adjusting screw 63 is screwed into the valve body 49 and is held in the adjusting position by the ball type click mechanism, and the tip thereof is in contact with the needle 64 in the diaphragm main body 57. The needle 64 is movably fitted in the axial center portion of the throttle body 57 along the axial direction, and has a passage cross-sectional area of a bypass passage 57c formed in the axial center portion and connecting the C chamber and the D chamber. It is structured to change. That is, when the adjusting screw 63 is tightened and moved to the right side in FIG. 18 with respect to the valve body 49, the passage cross-sectional area is narrowed and the amount of oil flowing through the bypass passage 57c is reduced. On the contrary, when the adjusting screw 63 is loosened, the oil amount increases.

The ball-type click mechanism for holding the adjusting screw 63 in the adjusting position has a structure in which the ball 63a held by the adjusting screw 63 is engaged with the vertical groove 49a of the valve body 49. The ball 63a has a compression coil spring 63c in the radial through hole 63b of the adjusting screw 63.
The adjustment screw 6
It is prevented from coming off by screwing 3 into the valve body 49. On the other hand, the vertical grooves 49a are formed so as to extend parallel to the axial direction of the adjusting screw 63 and open on the hole wall surface of the adjusting screw inserting hole, and are formed in a large number along the circumferential direction of the adjusting screw inserting hole.

That is, when the adjusting screw 63 is tightened or loosened, the ball 63a rotates together with the adjusting screw 63 so as to ride over the mountain portion between the adjacent vertical grooves 49a. In other words, the ball 63a is engaged with the vertical groove 49a by the spring force of the compression coil spring 63c, so that the adjusting screw 63 is prevented from rotating. In FIG. 18, the reference numeral 65 arranged near the adjusting screw 63 indicates that the adjusting screw 63 has the valve body 49.
It is a circlip to prevent it from falling off.

Further, in FIG. 18, reference numeral 66 is an O-ring mounted on the outer peripheral portion of the free piston 43, and 67 is also a piston ring. 68-73 are O-rings for maintaining liquid tightness or air tightness.

In the diaphragm member 42 thus constructed,
The oil passage passing through the small hole 57a of the throttle body 57 is shown in FIG.
The inflow paths 47a and 48a shown in FIG.
The oil passage passing through b forms the outflow passages 47b and 48b. Further, the check valve 60 is connected to the inflow path 4
The check valve 61 constitutes a check valve and a throttle installed in 7a and 48a, and the check valve 61 constitutes a check valve and a throttle installed in outflow paths 47b and 48b.

Next, the operation of the suspension device 41 configured as described above will be described. When the left and right hydraulic cylinders 2, 2 are stopped, the pressures in the oil chambers and the high pressure gas chamber of the suspension device 41 are substantially equal to each other.
That is, the hydraulic pressures of the upper oil chambers 7 of the left and right hydraulic cylinders are P ₁ , P ₂ , the pressure of the high pressure gas chamber 13 of the pressure regulator ₃ is P _3, and the pressure of the high pressure gas chamber 46 of the throttle member 42 is P _4. Then, P ₁ = P ₂ = P ₃ = P _{4 at} this time.

When the left and right hydraulic cylinders 2 and 2 contract, oil flows into the hydraulic paths 16 and 17 by the amount that the piston rod 10 is inserted into the cylinder body 5. At this time, assuming that the hydraulic pressures in the hydraulic paths 16 and 17 are substantially equal, the oil that has flowed out flows into the oil chamber 14 of the pressure regulator 3 and the oil chamber 45 of the throttle member 42, respectively. The flow direction of oil and the moving direction of each piston when the left and right hydraulic cylinders 2, 2 thus operate in phase are shown by solid arrows in FIG. Since the check valve 60 is provided in the path (inflow path 47a, 48a) flowing into the oil chamber 45 and the resistance is large, the amount of oil flowing into the oil chamber 45 flows into the oil chamber 14 of the pressure regulator 3. Less than the amount. On the other hand, the oil flows into the oil chamber 14 and the oil chamber 45 to generate a pressure difference between the oil chambers 14 and 45. The pressure difference at this time is the free piston 12 of the pressure regulator 3 and the free piston 43 of the throttle member 42.
Move in the cylinder bodies 11 and 44a and are absorbed.

That is, when the left and right hydraulic cylinders 2 expand and contract in the same direction due to pitching or bouncing of the vehicle body, the vibration of the vehicle body is damped mainly by the resistance generated when oil passes through the throttle 9 in the hydraulic cylinder 2. To be done.

When the left hydraulic cylinder 2 contracts and the right hydraulic cylinder 2 expands by turning the vehicle body to the right, the left hydraulic cylinder 2 causes oil to flow into the left hydraulic passage 16 as in the case described above. On the contrary, the right hydraulic cylinder 2 allows oil to flow in from the right hydraulic passage 17. The flow direction of oil and the moving direction of each piston at this time are indicated by broken line arrows in FIG.

When both hydraulic cylinders 2 operate in opposite phases in this way, the hydraulic pressure in the left hydraulic passage 16 becomes larger than the hydraulic pressure in the right hydraulic passage 17, and the oil in the left hydraulic passage 16 is throttled via the oil branch passage 47. It flows into the oil chamber 45 of the member 42, and then flows into the right hydraulic path 17 from the oil chamber 45 via the oil branch passage 48. When the oil flows into the oil chamber 45 of the throttle member 42, it flows as shown by the solid line arrow in FIG. 18, and when the oil flows out from the oil chamber 45, it also flows as shown by the broken line arrow.

That is, when the oil flows into the oil chamber 45, it flows from the branch pipes 53, 55 into the D chamber in the oil passage forming members 50, 51 in FIG. 18, and the C through the small hole 57a through the check valve 60. Pour into the room. Then, it flows into the oil chamber 45 from the C chamber through the communication passage 58 or the communication passage 59. Further, when the oil flows out from the oil chamber 45, it flows from the oil chamber 45 to the chamber C through the communication passage 58 or the communication passage 59 and the small hole 57.
It flows into chamber D from b through check valve 61. Then, it flows out from the D chamber to the branch pipes 53, 55 side. When the oil flows in and out as described above, it passes through the bypass passage 57c by the amount determined by the needle 64.

When both hydraulic cylinders 2 operate in opposite phases, the oil in and out of the oil chamber 14 of the pressure regulator 3 becomes extremely small. This is because the free pistons 12 of the pressure regulating device 3 can move only in the same direction because they are mechanically connected to each other, and hardly move transiently.

That is, if the vehicle body is rolling,
When the two hydraulic cylinders 2 operate in opposite phases, the resistance generated when the oil passes through the throttles 9 in each hydraulic cylinder 2 and the resistance generated when the oil passes through the inflow path 47a and the outflow path 48b of the throttle member 42. The vibration of the vehicle body is dampened by this. The resistance of the inflow path 47a is the resistance at the check valve 60 in the throttle member 42 (this resistance is indicated by ΔP ₁ in FIG. 19), and the resistance of the outflow path 48b is at the check valve 61 in the throttle member 42. Resistance (this resistance is indicated by ΔP ₂ in FIG. 19).

Therefore, according to the suspension device 41 thus constructed, when the left and right hydraulic cylinders 2, 2 operate in the same phase, the hydraulic cylinder 2 operates mainly by passing oil through the throttle 9 of the piston 6. It is damped by the resulting resistance. When both hydraulic cylinders 2 and 2 operate in opposite phases, it occurs when oil passes through the throttle 9 of the hydraulic cylinder 2 and the throttles (check valves 60 and 61) of the inflow passage 47a and the outflow passage 48b of the throttle member 42. The resistance damps the operation of the hydraulic cylinder 2. For this reason, the damping effect becomes large when a difference occurs in the operating directions of the two hydraulic cylinders 2, 2.

The resistances of the check valve 60 and the check valve 61 can be different from each other in addition to being equal to each other. In particular, the outflow route 48
The resistance at the check valve 61 located at b is set to the inflow path 4
By making it relatively larger than the check valve 61 located at 7a, it is possible to increase the resistance when the hydraulic cylinder 2 on the extension side tries to extend when the hydraulic cylinder 2 operates in the opposite phase. That is, it is possible to prevent the inside side of the vehicle body from rising during cornering, and obtain a transient roll characteristic in which the entire vehicle body sinks. Moreover,
The initial roll can be suppressed to improve the responsiveness. Further, when both the left and right wheels move up and down at the same time, the damping on the side of the throttle member 42 does not act, and even when one wheel goes over the projection on the road surface, the resistance against the push-up becomes relatively small, so that the riding comfort is high. It is good.

In this case, since the amount of oil flowing out from the oil chamber 45 of the throttle member 42 is smaller than the amount of inflowing oil, the pressure P ₄ in the oil chamber 45 is transiently the fluid in the pressure adjusting device 3. Since it becomes larger than the average value of the pressure (the average value of the pressure between the oil chamber 14 and the high-pressure gas chamber 13), the free piston 43 and the free piston 12 move so that the pressure is balanced. Specifically, free piston 1
2 moves slightly to the oil chamber 14 side, and the free piston 4
3 slightly moves to the high pressure gas chamber 46 side. These free pistons 43 and 12 will eventually return to their original positions if the hydraulic cylinder 2 is held in a stopped state after operating in the opposite phase by the same amount.

In the embodiments shown in FIGS. 16 to 19, the left and right wheels are suspended by the suspension device 41 according to the second invention. However, in the suspension device 41, front and rear wheels on the same side are paired. It can also be suspended. By doing so, it is possible to change the damping characteristics in pitching for bouncing and rolling. Moreover, if the resistance of the check valve 61 is made larger than that of the check valve 60, it is possible to prevent the front portion or the rear portion of the vehicle body from rising during the pitching operation.

Further, in suspending the wheels by the suspension device 41 according to the second invention, the form thereof can be changed as shown in FIGS. 20 and 21. In these figures, the same or equivalent members as those described in FIGS. 16 to 19 are designated by the same reference numerals, and detailed description thereof will be omitted.

FIG. 20 shows an example in which the left front wheel and the right rear wheel are suspended and the right front wheel and the left rear wheel are suspended by using the suspension system of the second invention. FIG. 21 shows that the hydraulic path of each hydraulic cylinder on the left front wheel side and the left rear wheel side is connected to one pressure adjusting cylinder of the suspension system of the second invention, and the right front wheel side and the right rear wheel are connected to the other pressure adjusting cylinder. An example in which the hydraulic paths of the respective hydraulic cylinders on the side are made to communicate with each other will be shown.

By connecting the front and rear wheels diagonally as shown in FIG. 20, it is possible to change the damping characteristics of pitching and rolling with respect to bouncing. Also, FIG.
As shown in FIG. 1, if the left and right wheels are connected together in the front and rear, the same effect as that of the embodiment shown in FIGS.

Further, in each of the embodiments shown in FIGS. 16 to 21, one throttle member 42 is connected to the left hydraulic passage 16,
Although an example in which both of the right hydraulic paths 17 are communicated is shown, a throttle member 42 may be provided for each of the left and right hydraulic paths as shown in FIG.

FIG. 22 is a diagram showing an example in which a second pressure adjusting cylinder is provided for each of the left and right hydraulic paths in the suspension system according to the second invention. In the figure, the same or equivalent members as those described in FIGS. 16 to 19 are designated by the same reference numerals and detailed description thereof will be omitted. In FIG. 22, reference numeral 7
Reference numeral 2 is a diaphragm member. The throttle member 72 has a structure in which the second pressure adjusting cylinder 44 is provided for each of the oil passage forming members 50 and 51 of the throttle member 42 shown in FIG. The throttle member 72 is in communication with both the left hydraulic path 16 and the right hydraulic path 17.

Even with this construction, the basic damping effect does not change from that of the embodiment shown in FIGS. Since the second pressure adjusting cylinder 44 exists in each of the left and right hydraulic paths, only the gas reaction force during rolling is different.

In addition, in the case of the structure shown in FIG. 22, the left and right hydraulic cylinders 2 and the throttle member 72 may be integrally formed to have a structure shown by being surrounded by an alternate long and short dash line in FIG. it can. In the figure, 73 is a free piston with a diaphragm. The free piston 73 has substantially the same structure as the piston 6 except that the piston rod 10 is not connected, and defines an upper oil chamber 7 and an oil chamber 45. The second hydraulic cylinder integrated hydraulic cylinder has substantially the same structure as a conventionally known single cylinder shock absorber with a reserve tank / base valve. Even with this structure, the same effect as that of the above embodiment can be obtained.

Next, a suspension system for a four-wheel vehicle according to the third invention will be described in detail with reference to FIGS. 23 to 25. FIG. 23 is a schematic configuration diagram of a suspension system for a four-wheel vehicle according to the third invention, FIG.
4 is a front view of the suspension system for a four-wheel vehicle according to the third invention, FIG.
5 is an enlarged sectional view of the pressure regulator. In these figures, the same or equivalent members as those described in FIGS. 1 to 7 are designated by the same reference numerals, and detailed description thereof will be omitted.

Reference numeral 81 denotes a suspension device according to the third invention, and this suspension device 81 is, for example, mounted on the front wheel side.
23 and 24, other suspension device constituent members such as a link mechanism and a cushion spring that support the front wheel to move up and down are omitted. Further, the suspension device 81 is configured in the same manner as the suspension device 1 of the first invention except that the structure of a pressure adjusting device 82 described later is different. First, the schematic configuration of the pressure adjusting device used in this embodiment will be described with reference to FIG.

The pressure adjusting device 82 shown in FIG. 23 has two pressure adjusting cylinders 84 and 85 formed in a cylinder body 83, one pressure adjusting cylinder 84 communicating with the left hydraulic passage 16 and the other pressure adjusting cylinder 84. The pressure cylinder 85 communicates with the right hydraulic path 17. The pressure regulating cylinder 84 is provided with a first free piston 86, and the pressure regulating cylinder 85 is provided with a second free piston 89 including a main free piston 87 and a sub free piston 88.

Further, in the cylinder body 83, one of the cylinder inner spaces partitioned by the first free piston 86 and the sub free piston 88 of the second free piston 89 is filled with high pressure gas to form a high pressure gas chamber 90, and the other. The cylinder interior space is filled with oil to form an oil chamber 91. Two oil chambers 91 are provided in the cylinder body 83 because two pressure adjusting cylinders are provided.

The first free piston 86 and the main free piston 87 of the second free piston 89 are connected by a connecting member 92.
Are integrally formed so as to be interlocked with each other and interlock with each other. The sub free piston 88 is movably provided with respect to the main free piston 87, and forms a sub oil chamber 91 a between the main free piston 87 and the high pressure gas chamber 90. Further, the main free piston 87 is provided with a throttle member 93 that connects the sub oil chamber 91a and the oil chamber 91 on the opposite side of the main free piston 87 to the sub free piston 88. That is, the sub oil chamber 91 a is connected to the right hydraulic passage 17 via the throttle member 93.
Will be connected to.

When mounting the suspension device 81 having the above-described structure on the vehicle body of an automobile, the pressure adjusting device 82 is used as shown in FIG.
4 and as shown in FIG. 25. In the pressure regulator 82 shown in FIGS. 24 and 25, the cylinder body 83 is formed in a cylindrical shape with a bottom, and the opening is closed by the bottom member 83a. The bottom member 83a is formed in a bottomed cylindrical shape having a tubular portion facing the inside of the cylinder body.
A main free piston 87 of a second free piston 89, which will be described later, is fitted inside the cylindrical portion of a.

Further, the bottom member 83a has a thin wall portion 83b formed at the tip portion of its cylindrical portion so as to have a smaller outer diameter. An oil chamber 91 is formed between the peripheral surface and the thin portion 83b. The oil chamber 91 is also provided between the inner bottom surface of the bottom member 83a and a second free piston 89 described later, in addition to the above-mentioned cylinder side portion.

In this pressure adjusting device 82, the first free piston 86 shown in FIG. 23 and the main free piston 87 of the second free piston 89 are integrally formed, and the second free piston is formed on the integrally formed free piston. The sub free piston 88 of the piston 89 is fitted and inserted. That is, the integrally molded free piston includes a small diameter portion (main free piston 87) fitted into the inner peripheral portion of the bottom member 83 a and a large diameter portion (first free piston portion fitted into the inner peripheral portion of the cylinder body 83). And 86) are formed into a bottomed cylindrical shape. The sub free piston 88 is movably fitted in the inner peripheral portion of the large diameter portion.

The outer diameter of the small-diameter portion and the outer diameter of the large-diameter portion are such that the volume increase and the volume decrease in the oil chambers 91, 91 when the integrally molded free piston moves are equal. Is set to. The positions of the integrally molded free piston and the sub free piston 88 when the volume of the oil chamber 91 becomes the maximum are shown by the chain double-dashed line F in FIG.

As the throttle member 93 provided on the main free piston 87 of the second free piston 89, the throttle body 25 is provided in the integrally formed free piston so as to define the inside of the hollow portion into chambers A and B. It is composed by. Since the structure of the diaphragm body 25 is the same as that shown in FIG. 3, the description thereof will be omitted here. The throttle body 25 used in this embodiment is supported by a support plate 94 with a communication hole that is press-fitted and fixed in the hollow portion of the integrally molded free piston.

That is, the main free piston 87 of the second free piston 89 is constituted by the small diameter portion of the integrally molded free piston and the throttle body 25. Further, the oil chamber A (sub oil chamber 91a) between the throttle body 25 and the sub free piston 88 is
5 and the oil chamber B in the main free piston 87, and is communicated with the right hydraulic path.

Reference numeral 95 denotes the cylinder body 83 and the bottom member 8.
3a is a nipple for connecting a communication pipe (not shown) of the left hydraulic path 16 and the right hydraulic path 17, 96 to 98 are O-rings, and 99 and 100 are piston rings.

In the pressure adjusting device 82 thus constructed,
The oil pressure in the left hydraulic path 16 is the oil chamber 91 on the cylinder side.
Acting on the large-diameter portion (first free piston 86) of the integrally-molded free piston, and the hydraulic pressure in the right hydraulic path 17 is passed through the oil chamber 91 on the bottom side of the bottom member 83a to make the small-diameter of the integrally-molded free piston smaller. It acts on the part (the main free piston 87 of the second free piston 89). That is, the bottom member 83a into which the small diameter portion of the integrally molded free piston is inserted and the cylinder body 83 into which the large diameter portion is inserted form a pressure adjusting cylinder for each hydraulic path.

Since the two oil chambers 91, 91 have the integrally-molded free pistons forming part of their wall surfaces, the volume change amount in each oil chamber 91 is always the same.

According to the suspension device 81 thus configured, when the left and right hydraulic cylinders 2, 2 operate in the same direction, substantially equal hydraulic pressure acts on the two oil chambers 91, 91 in the pressure regulating device 82. Therefore, the integrally-molded free piston only moves in the vertical direction in FIG. That is, at this time, since a small amount of oil passes through the throttle member 93, the operation of the hydraulic cylinder 2 is damped by the resistance generated by the oil passing through the throttle 9 of the piston 6.

When the two hydraulic cylinders 2, 2 operate in different directions, one of the two oil chambers 91, 91 of the pressure regulator 82 receives a large amount of oil pressure and the other does not. For example, if the left side hydraulic cylinder 2 expands and the right side hydraulic cylinder 2 contracts, the pressure in the oil chamber 91 on the cylinder side of the pressure regulator 82 becomes low and the bottom member 8
The oil chamber 91 on the bottom side of 3a has a high pressure.

In this case, the moving amount of the integrally molded free piston is reduced, and the oil is supplied to the oil chamber B by an amount corresponding to the difference in the amount of oil flowing into the two oil chambers 91.
Oil chamber A (sub oil chamber 91
Flow into a). At this time, the sub free piston 88 moves with respect to the integrally molded free piston so as to compress the high pressure gas. When the left side hydraulic cylinder 2 contracts and the right side hydraulic cylinder 2 extends, contrary to the case described above, the oil chamber A (the sub oil chamber 91a) moves to the oil chamber B.
The oil starts to flow. That is, when both hydraulic cylinders 2 and 2 are operated in different directions, a large amount of oil will pass through the throttle member 93, and at that time, the throttle 9 of the piston 6 of the hydraulic cylinder 2 and the throttle body 25 of the throttle member 4 The operation of the hydraulic cylinder 2 is damped by the resistance generated by the passage of oil through the oil. For this reason, the damping effect becomes large when a difference occurs in the operating directions of the two hydraulic cylinders 2, 2.

[0108]

As described above, according to the first aspect of the invention, 4
In a suspension system for a wheeled vehicle, the inside of the cylinder is divided into an upper oil chamber and a lower oil chamber by a piston with a throttle, and the cylinder body is connected to one of the wheel side and the vehicle body side, and the piston is connected to the other side of the wheel side. Has a hydraulic cylinder interposed between the vehicle side and the vehicle body side, and an oil chamber communicating with one of the upper and lower oil chambers of the hydraulic cylinder. The oil chamber and the high pressure gas chamber are defined by a free piston. A pressure regulating cylinder, and at least two of the four wheels are equipped with the hydraulic cylinder, and the pressure regulating cylinder is provided for each hydraulic path of the hydraulic cylinder, and the free pistons of the respective pressure regulating cylinders are interlocked with each other. In the suspension device for a four-wheeled vehicle according to the second aspect of the invention, the inside of the cylinder is throttled. It is defined by an attached piston into an upper oil chamber and a lower oil chamber, and the cylinder body is connected to one of the wheel side and the vehicle body side and the piston is connected to the other side and is interposed between the wheel side and the vehicle body side. Four wheels including a hydraulic cylinder and a pressure adjusting cylinder having an oil chamber communicating with one of upper and lower oil chambers of the hydraulic cylinder and having the oil chamber and the high-pressure gas chamber defined by a free piston The hydraulic cylinders are mounted on at least two of the hydraulic cylinders, the pressure adjusting cylinders are provided for each hydraulic path of the hydraulic cylinders, and the free pistons of the pressure adjusting cylinders are integrally configured to interlock with each other. A second pressure regulating cylinder, in which an oil chamber and a high-pressure gas chamber are defined by a free piston, is connected to the hydraulic passage via an inflow passage and an outflow passage on the oil chamber side. In the suspension system for a four-wheeled vehicle according to the third invention, the inside of the cylinder is divided into an upper oil chamber and a lower oil chamber by a piston with a throttle. A hydraulic cylinder that is formed between the wheel side and the vehicle body side and has a cylinder body connected to one of the wheel side and the vehicle body side and a piston connected to the other side. Damped by the passage of oil. If both hydraulic cylinders expand or contract in different directions, a large amount of oil will flow to the throttle member on the pressure regulating cylinder side.At that time, the throttle of the piston of the hydraulic cylinder and the throttle member on the pressure regulating cylinder side should be connected. The movement of the hydraulic cylinder is dampened by the passage of oil.

Therefore, when there is a difference in the operating directions of the two hydraulic cylinders, the throttle member on the pressure regulating cylinder side exerts a damping effect, so that the use conditions of each throttle provided in the device can be limited. This makes setting easier.

Further, since only one hydraulic path is required for each hydraulic cylinder to connect each hydraulic cylinder to the pressure regulating cylinder,
It also has the effect of simplifying piping.

Further, in the suspension device according to the second invention,
Since the flow path resistances of the inflow path and the outflow path communicating with the oil chamber of the second pressure adjusting cylinder can be individually set, the damping characteristics can be changed depending on whether the hydraulic cylinder extends or contracts. Therefore, it is possible to make more detailed settings.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of a suspension system for a four-wheel vehicle according to a first invention.

FIG. 2 is a front view of the suspension system for a four-wheeled vehicle according to the first invention.

FIG. 3 is an enlarged sectional view showing a pressure regulator and a throttle used in the suspension system for a four-wheel vehicle according to the first invention.

FIG. 4 is a front view of a suspension device using a pressure regulator having a structure with one free piston.

FIG. 5 is a cross-sectional view showing a pressure regulator having a structure with one free piston.

FIG. 6 is a front view of a suspension device using a pressure regulator having a structure in which two opposing free pistons are connected by a link.

FIG. 7 is a sectional view showing a pressure regulator having a structure in which two opposing free pistons are connected by a link.

FIG. 8 is a diagram showing an example in which left and right front wheels are suspended by the suspension device according to the first invention.

FIG. 9 is a diagram showing an example in which the left and right rear wheels are suspended by the suspension device according to the first invention.

FIG. 10 is a diagram showing an example in which the left and right front wheels are suspended and the left and right rear wheels are suspended by the suspension device according to the first invention.

FIG. 11 is a diagram showing an example in which the left and right front wheels are suspended and the right front wheel is suspended by the suspension device according to the first invention.

FIG. 12 is a diagram showing an example in which the left front wheel and the right rear wheel are suspended and the right front wheel and the left rear wheel are suspended by the suspension device according to the first invention.

FIG. 13 is a perspective view of the suspension device according to the first aspect of the present invention, in which one pressure adjusting device is used, one pressure adjusting cylinder is made to communicate with the hydraulic paths of the left front wheel side and left rear wheel side hydraulic cylinders, and the other pressure adjusting device is connected. FIG. 3 is a diagram showing an example in which hydraulic paths of hydraulic cylinders on the right front wheel side and the right rear wheel side are communicated with a pressure cylinder.

FIG. 14 is a perspective view of the suspension device according to the first aspect of the present invention, wherein one pressure adjusting device is used, one pressure adjusting cylinder is made to communicate with the hydraulic paths of the left front wheel hydraulic cylinder and the right rear wheel hydraulic cylinder, and the other pressure adjusting device is connected. FIG. 6 is a diagram showing an example in which hydraulic paths of a right front wheel side hydraulic cylinder and a left rear wheel side hydraulic cylinder are communicated with a pressure cylinder.

FIG. 15 is a diagram showing an example in which the same number of pressure adjusting cylinders as the hydraulic cylinders for each wheel are provided in the suspension device according to the first aspect of the present invention, and the hydraulic paths of the respective hydraulic cylinders are connected to separate pressure adjusting cylinders. .

FIG. 16 is a schematic configuration diagram of a suspension system for a four-wheel vehicle according to a second invention.

FIG. 17 is a front view of a suspension system for a four-wheel vehicle according to a second invention.

FIG. 18 is an enlarged sectional view showing a second pressure regulating cylinder.

FIG. 19 is a view for explaining the operation of the suspension device for a four-wheeled vehicle according to the second invention.

FIG. 20 is an example in which the left front wheel and the right rear wheel are suspended and the right front wheel and the left rear wheel are suspended using the suspension device of the second invention.

FIG. 21 is a diagram showing a hydraulic system in which the hydraulic paths of the left front wheel side and left rear wheel side hydraulic cylinders are connected to one pressure regulating cylinder of the suspension device of the second invention, and the other pressure regulating cylinder is connected to the right front wheel side and right rear side. In this example, the hydraulic paths of the hydraulic cylinders on the wheel side are communicated with each other.

FIG. 22 is a diagram showing an example in which a second pressure adjusting cylinder is provided for each of the left and right hydraulic paths in the suspension device according to the second invention.

FIG. 23 is a schematic configuration diagram of a suspension system for a four-wheel vehicle according to a third invention.

FIG. 24 is a front view of a suspension system for a four-wheel vehicle according to a third invention.

FIG. 25 is an enlarged cross-sectional view showing a pressure regulator used in a suspension system for a four-wheel vehicle according to a third invention.

[Explanation of symbols]

 1 Suspension Device 2 Hydraulic Cylinder 3 Pressure Regulator 4 Throttle Member 5 Cylinder Body 6 Piston 9 Throttle 11a Pressure Regulator Cylinder 12 Free Piston 13 High Pressure Gas Chamber 14 Oil Chamber 16 Left Hydraulic Route 17 Right Hydraulic Route 41 Suspension Device 42 Throttle Member 43 Free Piston 44 Second pressure control cylinder 45 Oil chamber 46 High pressure gas chamber 47a Inflow path 47b Outflow path 48a Inflow path 48b Outflow path 60 Check valve 61 Check valve 81 Suspension device 82 Pressure adjustment device 84 Pressure adjustment cylinder 85 Pressure adjustment cylinder 86 1st Free piston 87 Main free piston 88 Sub free piston 89 Second free piston 90 High pressure gas chamber 91 Oil chamber

Claims (3)

[Claims] 1. An inside of a cylinder is defined by a piston with a throttle into an upper oil chamber and a lower oil chamber, and a cylinder body is connected to one of a wheel side and a vehicle body side and a piston is connected to the other side of the wheel side to a wheel side. It has a hydraulic cylinder interposed between the vehicle body side and an oil chamber communicating with one of the upper and lower oil chambers of the hydraulic cylinder. The oil chamber and the high pressure gas chamber are defined by a free piston. A pressure cylinder, at least two of the four wheels are equipped with the hydraulic cylinder, the pressure regulating cylinder is provided for each hydraulic path of the hydraulic cylinder, and the free pistons of the respective pressure regulating cylinders are interlocked with each other. A suspension system for a four-wheeled vehicle, which is configured integrally and communicates the hydraulic paths with each other through a throttle member. 2. The inside of the cylinder is divided into an upper oil chamber and a lower oil chamber by a piston with a throttle, and the cylinder body is connected to one of the wheel side and the vehicle body side and the piston is connected to the other side to connect the wheel side to the wheel side. It has a hydraulic cylinder interposed between the vehicle body side and an oil chamber communicating with one of the upper and lower oil chambers of the hydraulic cylinder. The oil chamber and the high pressure gas chamber are defined by a free piston. A pressure cylinder, at least two of the four wheels are equipped with the hydraulic cylinder, the pressure regulating cylinder is provided for each hydraulic path of the hydraulic cylinder, and the free pistons of the respective pressure regulating cylinders are interlocked with each other. A second pressure regulating cylinder, which is integrally configured and has an oil chamber and a high-pressure gas chamber defined by a free piston, is provided in the hydraulic path on the oil chamber side inflow path. And communication via the outflow path,
A suspension system for a four-wheeled vehicle, wherein throttles are respectively provided in the inflow path and the outflow path. 3. The inside of the cylinder is divided into an upper oil chamber and a lower oil chamber by a piston with a throttle, and the cylinder body is connected to one of the wheel side and the vehicle body side and the piston is connected to the other side to connect the wheel side to the wheel side. It has a hydraulic cylinder interposed between the vehicle body side and an oil chamber communicating with one of the upper and lower oil chambers of the hydraulic cylinder. The oil chamber and the high pressure gas chamber are defined by a free piston. A pressure cylinder, at least two of the four wheels are equipped with the hydraulic cylinder, the pressure regulating cylinder is provided for each hydraulic path of the hydraulic cylinder, and the free pistons of the respective pressure regulating cylinders are interlocked with each other. It is configured as an integral unit, and the free piston of one of the pressure regulating cylinders is linked to the free piston of the other pressure regulating cylinder. -A piston and an auxiliary free piston that is movably provided with respect to the main free piston and that forms an auxiliary oil chamber between the main free piston and the high-pressure gas chamber. A suspension system for a four-wheel vehicle, characterized in that the suspension system communicates with the hydraulic path via a throttle member provided in the.