JP2702511B2 - Vehicle suspension device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial application field) The present invention relates to a telescopic cylinder which is installed between a sprung portion and a unsprung portion of a vehicle and provided independently for each wheel. More particularly, the present invention relates to a suspension device that changes and adjusts suspension characteristics by supplying and discharging fluid, and more particularly to an arrangement structure of a control valve and the like for controlling supply and discharge of fluid to and from a cylinder.

(Prior Art) Today, there are various types of suspension devices mounted on vehicles, and among them, a device called an active suspension device attracts attention as a device that can improve the ride comfort and stabilize the vehicle body posture. Have been. This one is
For example, as disclosed in European Patent Application Publication No. 0114757 and the like, a cylinder which can expand and contract according to the relative displacement between a vehicle body as a sprung portion and a wheel side as a unsprung portion in a vehicle is provided. A control valve for controlling the supply and discharge of the fluid to and from the cylinder fluid chamber is provided in the middle of the fluid passage, and the fluid chamber of the cylinder is connected to a pressure source such as a pump via a fluid passage. With this control valve, the suspension characteristics are changed and adjusted by supplying and discharging fluid to and from the fluid chamber of each cylinder.

(Problems to be Solved by the Invention) By the way, in this type of suspension device,
Since each cylinder and the pressure source are configured to communicate with each other through the fluid passage, the arrangement position of each control valve on the vehicle body does not matter. However, if the control valve is arranged so that the distance of the fluid passage to the cylinder becomes long, the pressure loss in the cylinder fluid chamber becomes large due to an increase in piping resistance therebetween, and as a result, the supply of fluid to the cylinder becomes large. There is a difficulty that the discharge control becomes inaccurate and a predetermined suspension characteristic cannot be obtained accurately.

Further, in order to generate a reaction force against the load from the wheel side in each cylinder, it is necessary to supply high-pressure oil to the fluid chamber. In this case, an accumulator is connected to an oil passage from the oil pump to the control valve to accumulate pressure in the accumulator, and the high-pressure oil in the accumulator can be quickly supplied to the cylinder fluid chamber at a stretch with the opening operation of the control valve. That is done.

The present invention has been made in view of such a point, and an object thereof is to specify an arrangement structure of a control valve and an accumulator in a fluid passage between an oil pump and a cylinder arranged corresponding to each wheel. Another object of the present invention is to reduce the piping resistance between the control valve and the accumulator and the cylinder as much as possible, and to control the supply and discharge of hydraulic oil to and from the cylinder accurately and quickly.

(Means for Solving the Problems) In order to achieve the above object, a solution of the present invention is provided between a sprung portion and a unsprung portion of a vehicle, and is provided independently for each wheel. An oil pump that discharges hydraulic oil, in a vehicle suspension device that changes and adjusts suspension characteristics by supplying and discharging hydraulic oil to and from a fluid chamber of an extendable cylinder,
A plurality of accumulators for accumulating hydraulic oil discharged from the oil pump; and a plurality of accumulators provided in an oil passage downstream of the accumulators, for controlling the supply and discharge of the hydraulic oil accumulated in the accumulators to the cylinder fluid chamber. A plurality of control valves independently provided so as to correspond to each other, wherein the control valve is divided into two valve units for left and right front wheels and for left and right rear wheels,
In addition, the accumulator is provided integrally with each valve unit, and the valve units are separately arranged in the vehicle longitudinal direction so as to be in the vicinity of the corresponding wheel set.

(Operation) With the above configuration, in the present invention, the plurality of control valves are divided into two valve units for the left and right front wheels and for the left and right rear wheels, and are integrated with the corresponding accumulators.
Since it is arranged separately in the vehicle longitudinal direction so as to be in the vicinity of the corresponding wheel set, the length of the fluid passage between the valve units and accumulators arranged for the left and right front wheels and the cylinders for the left and right front wheels, In addition, the lengths of the fluid passages between the valve units and the accumulators arranged for the left and right rear wheels and the cylinders for the left and right rear wheels are all reduced. For this reason, the pipe resistance between the control valve and the accumulator and the corresponding cylinder for the wheel is reduced,
Since each pressure loss of the hydraulic oil supplied to the cylinder and the hydraulic oil discharged from the cylinder according to the switching of the control valve is reduced, the supply and discharge control of the hydraulic oil to and from the cylinder can be performed accurately and quickly. is there.

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings.

FIG. 7 schematically shows the overall configuration of a suspension device according to an embodiment of the present invention, wherein 1 is a vehicle body constituting a sprung portion, 2 is a front wheel, 3 is a rear wheel, and these wheels 2, 3 ( Before/
The rear wheel) is supported by a wheel support member (not shown) such as an axle, and the unsprung portion is constituted by the wheels 2, 3 and the wheel support member.

As shown in FIG. 6, extendable hydraulic cylinders 4 to 7 are provided between the sprung portion and the unsprung portions. Each of the cylinders 4 to 7 includes a cylinder body 4a to 7a connected to the vehicle body 1 and a cylinder body 4a to 7a.
4a to 7a are fitted reciprocally in the cylinder body 4a to
Pistons 4c to 7c defining and defining hydraulic chambers 4b to 7b in the inside of the piston rods 4d to 7d.The pistons 4c to 7c are integrally attached with downwardly extending piston rods 4d to 7d, respectively.
7d are connected to the respective wheel support members (wheels 2, 3). Further, the hydraulic chambers 4b to 7b of the cylinders 4 to 7 are provided.
Is an oil pump 9 serving as a hydraulic pressure source through an oil passage 8.
And the cylinders 4-
The same number (four) of control valves 11 to 14 as the wheels 2 and 3 are provided for controlling the supply and discharge of oil to and from the hydraulic chambers 4b to 7b. Each of the control valves 11 to 14 is a control unit.
The control unit 70 includes a pair of front and rear vehicle height sensors 71, 71 for detecting a vehicle height (height of the vehicle body 1) and a pressure at a predetermined portion in the oil passage 8. , And an acceleration sensor 73 for detecting the vertical acceleration of the vehicle body 1, and each control valve is controlled based on these signals.
By controlling the operation of the cylinders 11 to 14, the oil is supplied to and discharged from the hydraulic chambers 4b to 7b of the cylinders 4 to 7, thereby changing and adjusting the suspension characteristics of the vehicle.

The oil pump 9 is, as shown in FIG. 6, an oil pump composed of a vane pump for a power steering device.
For example, a radial piston pump which is a double pump 10 is provided. These two pumps 9 and 10 are driven by an on-board engine (not shown) disposed in an engine room 1a (see FIG. 2) in the front part of the vehicle body 1. You. The suction side of the oil pump 9 is connected to a reserve tank 15 via a suction passage 8h. On the other hand, a supply passage 8a is connected to the discharge side, and a downstream portion of the supply passage 8a is branched into two branch supply passages 8b, 8b on a front wheel side and a rear wheel side. Are further branched and connected to two branch supply passages 8c. The downstream ends of the four branch supply passages 8c are connected to control valves 11 to 14 corresponding to the cylinders 4 to 7, respectively.

Each of the control valves 11 to 14 is a three-port proportional solenoid valve capable of taking three positions of supply, discharge, and shut-off, and the downstream ends of the branch supply passages 8c are connected to the supply ports 11a to 14a. Further, a discharge passage 8d is connected to the discharge ports 11b to 14b, and a downstream end of the branch discharge passage 8d is connected to a front-wheel or rear-wheel-side collective discharge passage 8e, 8e together with the other same passage 8d. The downstream ends of the discharge passages 8e, 8e are gathered together in a collective discharge passage 8f and connected to the reservoir 15. On the other hand, the supply / discharge ports 11c to 14c communicate with the hydraulic chambers 4b to 7b of the cylinders 4 to 7 via the supply / discharge passage 8g.

The front wheel side branch supply passage 8b has three front wheel main accumulators 16, 16,..., And the rear wheel side branch supply passage 8b has one main accumulator.
The two main accumulators 17 for the rear wheels are branched and connected, and these accumulators 16 and 17 smooth the pulsation of the discharge pressure of the oil pump 9 and set the line pressure of the pressure line in the supply passages 8a to 8c by accumulating the pressure. Things. Also, a front wheel return accumulator 18 is connected to the front wheel side collective discharge passage 8e, and a rear wheel return accumulator 19 is branch connected to the rear wheel side collective discharge passage 8e, and these accumulators 18, 19 are controlled valves 11 to 1 respectively.
A sudden increase in pressure when oil is discharged to the discharge passages 8d to 8f in accordance with the switching operation of 4 is absorbed to suppress a so-called water hammer phenomenon.

Reference numerals 20 and 21 denote gas springs connected in parallel to the hydraulic chambers 4b to 7b of the cylinders 4 to 7 via communication passages 8i and 8j, respectively. The gas chambers 20a and 21a are formed by bellows similarly to the accumulator. And oil chambers 20b and 21b
b, 21b are communicated with the hydraulic chambers 4b-7b of the cylinders 4-7,
Gas is sealed in the gas chambers 20a and 21a, and the gas chambers 20a and 2a are filled with gas.
Hydraulic chambers 4b-7b of cylinders 4-7 by compression of gas in 1a
Pressure fluctuations in a relatively high frequency range, ie, each wheel 2,3
It absorbs the vibration of And these two gas springs
Orifices 22, 23 having different flow rate characteristics are provided in communication passages 8i, 8j between 20, 21 and the cylinders 4 to 7, respectively.
The two types of orifices 22 and 23 are used to obtain vibration absorption characteristics in a wide frequency range.

To explain the auxiliary function, 9a is a relief valve in the pump for adjusting the discharge pressure inside the oil pump 9,
Reference numeral 24 denotes an unload relief valve interposed between the supply passage 8a and the collective discharge passage 8f.
The line pressure set by 7 is the upper limit (for example, 160 kg / c
When the pressure rises above m ² ), the valve opens to relieve the discharge oil from the oil pump 9 to the reserve tank 15, and when the line pressure falls below the lower limit (for example, 120 kg / cm ² ), the valve closes to reserve the discharge oil. Stop the relief of 15 to the tank,
The line pressure is kept within a set range. Each of the above supply and discharge passages
8g for normally closed shut-off valve 25 with line pressure as pilot pressure
An electromagnetic switching valve 26 is disposed in a pilot passage 8k that connects the shutoff valve 25 and the branch supply passage 8b (pressure line). The switching valve 26 is connected to the discharge passage 8 via a relief passage 8l. 8d, when the electromagnetic switching valve 26 is energized, the pilot passage 8k is opened and the relief passage 8l is closed to close the shut-off valve 25 and open the supply / discharge passage 8g, while the non-energized By closing the passage 8k and reducing the pilot pressure to the shut-off valve 25 to zero, the shut-off valve 25 is opened to close the supply / discharge passage 8g, that is, the ignition key switch of the vehicle is turned off.
When the switching valve 26 is de-energized by the F operation, or when the line pressure decreases due to the failure of the hydraulic piping and the pilot pressure of the shut-off valve 25 disappears even when the switching valve 26 is energized, the shut-off valve 25 is closed. The oil is closed in the hydraulic chambers 4b to 7b of the cylinders 4 to 7 by making valves.

A pilot pressure reducing valve 27 is provided in each of the branch supply passages 8c. The pressure reducing valve 27 is a branch supply passage downstream of the pressure reducing valve 27.
The difference between the oil pressure on the pressure reducing valve 27 and the oil pressure on the downstream side is maintained at a constant value using the oil pressure of 8c and the oil pressure of the supply / discharge passage 8g as pilot pressure. Similarly, a pilot pressure reducing valve 28 is provided in each of the branch discharge passages 8d.
Numeral 28 is used to maintain the difference between the oil pressure on the pressure reducing valve 28 and the oil pressure on the downstream side at a constant value, using the oil pressure of the upstream branch discharge passage 8d and the oil pressure of the supply / discharge passage 8g as pilot pressure.
Further, between each of the supply and discharge passages 8g and the branch discharge passage 8d,
When the pressure in the supply / discharge passage 8g exceeds the limit value, a relief valve 29 is provided to open the valve and relieve the oil to the discharge passage 8d. In FIG. 6, reference numeral 48 denotes an oril filter.

Of the above hydraulic devices, the control valves 11 and 12 corresponding to the left and right front wheels 2 and 2, the shutoff valves 25 and the switching valves 26, the pressure reducing valves 27 and 28 on the pressure side and the return side, and the relief valves 29 are for the front wheels. The valve unit 30 is integrally provided with the main accumulators 16, 16,... And the return accumulator 18 on the front wheel side. Similarly, control valves 1 corresponding to the left and right rear wheels 3, 3 are also provided.
3, 14, each shut-off valve 25, the switching valve 26, the pressure reducing valves 27 and 28 on the pressure side and the return side, and each relief valve 29 are unitized as a rear wheel valve unit 31.
A main accumulator 17 and a return accumulator 19 on the rear wheel side are provided side by side. Therefore, in this embodiment, the four control valves 11 to 14 are divided into two for front wheels and two for rear wheels by unitization.

FIGS. 1 to 5 show the arrangement of the hydraulic equipment in the vehicle body 1. In the drawings, reference numerals 50, 50 denote left and right front side frames extending in the front-rear direction on the left and right sides of the front bottom surface of the vehicle body. A front cross member 51 (first section) extending in the left-right direction extends between the front ends of the side frames 50, 50.
A frame-shaped shroud member 52 (radiator shroud) having a shroud door upper 52a is provided upright behind the cross member 51. Head lamp mounting members are provided on both left and right sides of the shroud member 52. Shroud panels 53 having an opening 53a are arranged. A radiator 54 is disposed behind the shroud member 52. Body 1 of each shroud panel 53
Outside upper and lower reinforcements
The front side frame 50 and upper reinforcement 55 are located behind the shroud panel 53.
A wheel apron 56 is provided to connect the apron. The wheel apron 56 has a wheel house 56a at a portion corresponding to the front wheel 2, and a strut tower 56b bulging upward is formed at the center thereof.
The cylinder bodies 4a, 5a of the cylinders 4, 5 for the front wheels are connected to the cylinder body. A front fender 57 extending in the front-rear direction is disposed outside the vehicle body 1 of the wheel apron 56, and the front fender 57 is joined to the upper reinforcement 55 at an upper edge thereof.

Also, in FIG. 2, 58, 58 (only one is shown)
Are left and right side sills extending in the front-rear direction on the left and right sides of the rear bottom surface of the vehicle body. The left and right edges of a floor panel 59 are joined to the both side sills 58, 58.
Is formed with a tunnel portion 59a extending in the front-rear direction formed by bulging the left and right central portions upward. A rear cross member 60 (third cross member) extending in the vehicle width direction and connecting the left and right side sills 58, 58 is disposed on the upper surface of the floor panel 59. After the rear cross member 60, the rear cross member 60 extends in the same direction. A suspension cross member 61 for wheels is provided. The rear wheel of each of the side sills 58 is joined to a wheel house inner panel 62. The wheel house inner panel 62 has a strut tower 63 bulging upward at a portion corresponding to the rear wheel 3; The cylinder bodies 6a, 7a of the rear wheel cylinders 6, 7 are connected.

As shown in FIGS. 1 to 3, the wheel apron 56 and the fender 57
Space S ₁ is formed between said front-wheel valve unit 30 in the space S _1, is arranged in a state where the main accumulator 16, 16, ... and the return accumulator 18 is housed in a sealed box-like casing 32 ing. Supports 32a and 32b are respectively provided on the right side (the left side in the figure) and the left side (the same right side) of the case 32. The right support 32a is mounted on the left front side frame 50 by the mount rubber 33 and the bracket. It is connected and supported via 34. Meanwhile, the left support
32b is connected and supported by a bumper slider 65 that supports the front bumper 64 of the vehicle so as to be slidable rearward with a load of a predetermined value or more. With this structure, the front wheel valve unit 30 is rubber-mounted on the vehicle body 1.

On the other hand, the reserve tank 15 is disposed in the space S ₂ formed by the wheel apron 56 and the fender 57 in the corner portion of the front right of the vehicle body 1.

As shown in FIGS. 2 and 5, in the floor panel 59, the rear cross member 50 and the right side sill 58 are provided.
A portion surrounded by the tunnel portion 59a and the suspension cross member 51 have been bulged upward, a rectangular recess 59b on the bottom surface floor panel 59 having an inner space S ₃ which is open downward by its bulging form are, the rear wheel valve unit 31 in the space S _3, are arranged in a state the main accumulator 17 and a return accumulator 19 (not shown) is housed supported by a support bracket 35. A protector 36 that covers the valve unit 31 and the like is disposed below the valve unit 31 and the like. The protectors 36 are mounted on front and rear ends of the support bracket 35, respectively.
37, 37 (only the front side is shown). In FIG. 2, reference numeral 66 denotes an engine exhaust pipe arranged below the left side of the floor panel 59 of the vehicle body 1.

Therefore, in this embodiment, two control valves 11, 1 for the front wheels are used.
2 is disposed in the front and rear direction of the vehicle body so as to be near the two cylinders 4 and 5 on the front wheel side and two control valves 13 and 14 for the rear wheel are near the two cylinders 6 and 7 for the rear wheel. I have.

Reference numerals 38 to 46 denote hydraulic pipes forming the oil passage 8. That is, 38 is the reserve tank 15 and the oil pump 9
The suction pipe 39 connects the suction side of the oil pump 9 to the discharge side of the oil pump 9 and the front wheel valve unit 30 (specifically, the right and left pressure reducing valves 27, 27 and the front wheel main accumulators 16, 16, ...). Main pressure piping, 40
Is a front left pipe connecting the front wheel valve unit 30 (left front wheel control valve 11) and the left front wheel cylinder 4, and 41 is a front wheel valve unit 30 (right front wheel control valve 12) and a right front wheel cylinder 5 And 42 are front-wheel rattan pipes for connecting the front tank valve unit 30 (left and right return pressure reducing valves 28 and 28) and the reserve tank 15, and 43 is a rear-wheel valve unit 31 (right and left). The return piping for the rear wheel connecting the return side pressure reducing valve 28, 28) to the reserve tank 15, 44
Is branched from a main pressure pipe 39 in a case 32 accommodating the front wheel valve unit 30, and is connected to the main pressure pipe 39 and the rear wheel valve unit 31 (the left and right pressure reducing valves).
27, 27 and a branch pressure pipe connecting the rear wheel main accumulator 17). Also, in FIG.
45 is a pipe for the left rear wheel connecting the valve unit 31 for the rear wheel (the control valve 13 for the left rear wheel) and the cylinder 6 for the left rear wheel, and 46 is a valve unit 31 for the rear wheel (the control valve 14 for the right rear wheel). ) Is connected to the right rear wheel cylinder 7.

As shown in FIGS. 1, 2, and 4, the oil discharged from the oil pump 9 is supplied to the cylinder 4 for each wheel.
Main pressure piping 39 to be supplied to 7 to 7, right front wheel piping
41 and the branch pressure pipe 44 are the return pipe 43 for the front wheels.
Together with the shroud member in the shroud member 52
52b, a pair of left and right piping harnesses 47,
47 is fixedly supported on the shroud drawer 52b.

As shown in FIG. 2, the branch pressure pipe 44 for supplying the oil discharged from the oil pump 9 to the rear wheel cylinders 6 and 7 is connected to the vehicle body 1 together with the rear wheel return pipe 43.
On the right side of the vehicle body 1, that is, on the side opposite to the exhaust pipe 66 disposed on the left side of the vehicle body 1.

Therefore, in the above embodiment, when the ignition key switch is turned on and the engine is in the operating state, oil is discharged from the oil pump 9 driven by the engine, and the main accumulator is adjusted by adjusting the unload relief valve 24. A predetermined range of line pressure is accumulated in the pressure lines (supply passages 8a to 8c) communicating with 16,16. In addition, each switching valve 26 is turned ON by the ON operation of the ignition key switch, and accordingly, each shutoff valve 25 that has been closed is switched to the open state, and the supply / discharge passage 8g is opened. The control unit 70 controls the control valves 11 to 11 based on the vehicle height detected by each vehicle height sensor 71, the oil pressure detected by the pressure sensor 72, and the vertical acceleration of the vehicle body 1 detected by each speed sensor 73. The operation of the control valve 14 is controlled, and the high pressure oil of the pressure line is supplied to the hydraulic chambers 4b to 7b of the cylinders 4 to 7 by the control of the control valves 11 to 14, or the oil in the hydraulic chambers 4b to 7b is reserved. After being discharged to the tank 15, the suspension characteristics of the vehicle are changed and adjusted to predetermined characteristics.

In the case of this embodiment, the four control valves 11 to 14 are divided into front and rear wheel side valve units 30 and 31 for the front wheel and the rear wheel, and two control valves 11 and 12 for the front wheel (for the front wheel). The valve unit 30) is located at a position close to the front wheel cylinders 4 and 5 at the front left corner of the vehicle body 1, and has two control valves 13 and 14 for the rear wheels.
Since the (rear wheel valve unit 31) is disposed below the floor panel 59 at the rear of the vehicle body 1 and at a position close to the rear wheel cylinders 6, 7, two control valves 11, 12 for the front wheels and their The length of each supply / discharge passage 8g between the front valves 4 and 5 corresponding to the control valves 11 and 12, and the two control valves 13 and 14 for the rear wheels
The length of each supply / discharge passage 8g between the control valves 13 and 14 and the rear wheel cylinders 6 and 7 corresponding to the control valves 13 and 14,
In each case, the length is shorter than the case where it is arranged at the center. For this reason, the pipe resistance in the pipe connecting the control valves 11 to 14 and the wheel cylinders 4 to 7 corresponding to the control valves 11 to 14 is reduced, and the control valves 4 to 7 are switched accordingly. The pressure loss of the oil supplied from the pressure lines to the hydraulic chambers 4b to 7b of the cylinders 4 to 7 and the pressure loss of the oil discharged from the hydraulic chambers 4b to 7b to the discharge passages 8d to 8f are all reduced. 7 can be accurately and quickly performed, and the desired suspension characteristics can be obtained accurately.

Also, the main accumulators 16, 16,... For the front wheels are integrated with the front valve unit 30, and the main accumulator 17 for the rear wheels are integrated with the rear valve unit 31, respectively.
Since these main accumulators 16 and 17 are also disposed close to the corresponding wheel cylinders 4 to 7, respectively, the distance from the accumulators 16 and 17 to the control valves 11 to 14 is also reduced, and the accumulators 16 and 17 are connected to the cylinders 4 to 7. The oil supplied to the cylinder 7 can be supplied with its pressure drop suppressed, and the supply and discharge control of the oil to and from the cylinders 4 to 7 can be performed more accurately and quickly.

Further, enclosure at corners of the front left of the vehicle body 1 the main accumulator 16, 16 in the space S ₁ formed between the wheel apron 56 and the fender 57, ... and the return accumulator 18 with front-wheel accumulator 30 Because it is arranged in a state stored in the case 32,
Even if both of the accumulators 16 and 18 are damaged, the scattered oil does not hit the engine in the engine room 1a at all, which is advantageous.

A main pressure pipe for supplying oil discharged from the oil pump 9 to the cylinders 4 to 7 for each wheel.
39, since the right front wheel pipe 41 and the branch pressure pipe 44 are arranged in front of the shroud drawer 53a of the shroud member 53 together with the front wheel return pipe 42, these pipes 39, 41, 44 Is damaged and high-pressure oil is ejected, the oil is blocked by the shroud member 52 and the radiator 54 disposed behind the shroud member 52,
Oil can reliably be prevented from jumping into the engine room 1a.

In addition, since these pipes 39, 41, and 44 are exposed to the cold traveling wind before being introduced into the radiator 54, the oil flowing inside can be cooled, and the cooling property of the oil that generates heat by high pressure can be improved. .

Further, in the floor panel 59, a portion surrounded by the rear cross member 60, the right side sill 58, the tunnel portion 59a, and the suspension cross member 61 is swelled upward, and is opened downward by the swelling floor panel 59. space S ₃ is formed, the valve unit 31 for the rear wheels in the space S _3, since the main accumulator 17 and the return accumulator 19 is disposed, even a so-called belly beating state body 1 is in contact with the road surface, These devices are unlikely to come into contact with the road surface, and the damage can be suppressed. Moreover, since the protector 36 is provided below each device, the device does not directly contact the road surface, which is more advantageous.

Furthermore, since the accumulators 17, 19, etc. are arranged below the floor panel 59, that is, outside the vehicle, even if the accumulators 17, 19, etc. are damaged, the oil scattered along with them is shielded by the floor panel 59, and It does not enter the room.

In addition, as shown in FIG. 2, a branch pressure pipe 44 for supplying the oil discharged from the oil pump 9 to the rear wheel cylinders 6, 7 is provided with an exhaust pipe 66 located on the right side of the vehicle body 1, that is, on the left side of the vehicle body 1. The oil flowing in the pressure pipe 44 is not heated by the exhaust pipe 66 heated by the exhaust heat and rises to a high temperature because the oil is flowing along the right side sill 58 on the opposite side to the control valves 11 to 11. It is possible to suppress the temperature rise of the oil seal to a temperature equal to or higher than the heat resistance assurance temperature of the oil seal at 14, etc., to effectively prevent the thermal deterioration, and to operate the control valves 11 to 14, etc. stably.

The pressure pipe 44 and the return pipe 43 are exhaust pipes.
Even if these pipes 43 and 44, especially the pressure pipe 44 are damaged and fall into a faulty state, there is no possibility that the ejected oil hits the hot exhaust pipe 66.

(Effects of the Invention) As described above, according to the present invention, suspension characteristics are changed and adjusted by supplying and discharging hydraulic oil to and from a cylinder installed between a sprung portion and a unsprung portion of a vehicle. In the device, a plurality of control valves for controlling the supply and discharge of fluid to and from the cylinder are divided into two valve units, one for left and right front wheels and one for left and right rear wheels, and integrated with a corresponding accumulator to form a corresponding wheel set. By arranging them separately in the longitudinal direction of the vehicle so as to be close to each other, the piping resistance between the control valve and the accumulator and the corresponding wheel cylinder is reduced, and the cylinder is supplied and discharged according to the switching of the control valve. Pressure loss of the hydraulic oil to be supplied can be reduced. Characteristics can be obtained accurately.

[Brief description of the drawings]

The drawings show an embodiment of the present invention. FIG. 1 is a front view of the arrangement structure of the hydraulic system as viewed from the front of the vehicle body, FIG. 2 is a plan view of the same as viewed from above, and FIG. III-III line sectional view, FIG. 4 is the same IV-IV line sectional view, FIG. 5 is the same VV line sectional view,
FIG. 6 is a hydraulic circuit diagram, and FIG. 7 is a schematic side view schematically showing an overall configuration of a suspension device. DESCRIPTION OF SYMBOLS 1 ... Body, 2 ... Front wheel, 3 ... Rear wheel, 4-7 ... Hydraulic cylinder, 4b-7b ... Hydraulic chamber (fluid chamber), 9 ... Oil pump, 11-14 ... Control valve, 16, 17 Main accumulator, 20, 21 Gas spring, 30 Valve unit for front wheel, 31 Valve unit for rear wheel, 38 to 46 Hydraulic piping, 52 Shroud member, 56 Wheel apron, 57 ... Front fender, 58 ... Side sill, 59 ...
… Floor panel, 59a …… Tunnel part, 60 …… Rear cross member, 61 …… Suspension cross member, 65 ……
Bumper slider, S ₁ , S ₃ …… space.

 ────────────────────────────────────────────────── ─── Continuing from the front page (72) Inventor Hirokazu Kumada 3-1, Shinchi, Fuchu-cho, Aki-gun, Hiroshima Prefecture Inside Mazda Co., Ltd. (56) References Japanese Utility Model 60-180618 (JP, U) Japanese Utility Model Sho Akira 61-27713 (JP, U) Actually open 1987-185608 (JP, U)

Claims (1)

(57) [Claims] 1. A vehicle which is installed between a sprung portion and a unsprung portion of a vehicle,
In a vehicle suspension system in which suspension characteristics are changed and adjusted by supplying and discharging hydraulic oil to a fluid chamber of a telescopic cylinder independently provided corresponding to each wheel, the hydraulic oil is discharged. An oil pump, a plurality of accumulators for accumulating hydraulic oil discharged from the oil pump, and an oil passage provided in an oil passage downstream of the accumulator, for supplying and discharging hydraulic oil accumulated in the accumulator to the cylinder fluid chamber. A plurality of control valves independently provided so as to correspond to the cylinders, respectively, wherein the control valves are divided into two valve units for left and right front wheels and for left and right rear wheels, and The above accumulator is provided integrally with the valve unit of A suspension system for a vehicle, wherein the vehicle suspension device is arranged separately in the longitudinal direction of the vehicle body so as to be in the vicinity of the wheel set.