JP2023160544A - Active suspension device for vehicle - Google Patents

Abstract

To solve the problem that a conventional active suspension requires a hydraulic pump and complicated hydraulic piping for a hydraulic pressure for vehicle height control and has a problem of cost increase and a problem of energy consumption for driving the hydraulic pump, and that a conventional semi-active suspension for controlling damping force requires a control mechanism of a special structure for controlling the damping force.SOLUTION: An active suspension device for a vehicle is configured to: separate an accumulator which absorbs oil quantity change by expansion and contraction of a rod of a shock absorber; connect an actuator and/or an accumulator through a connection cover provided with a solenoid valve on the shock absorber; integrally form all hydraulic circuits by using the connection cover as a hydraulic manifold block to eliminate need for tubular hydraulic piping; and complete the hydraulic circuit in each axle in a simple structure. Since an action utilizes a hydraulic pressure generated by the expansion and contraction of the rod of the shock absorber expanded and contracted by vibration during traveling, neither a hydraulic pump nor its driving energy consumption is required.SELECTED DRAWING: Figure 1

Description

The present invention provides an active suspension device that includes a connecting cover over a shock absorber of a vehicle such as an automobile, and uses the shock absorber as a hydraulic power source for a vehicle height control actuator, and controls the damping force of the shock absorber using a solenoid valve. The present invention relates to a semi-active suspension device with passive elements.

Suspensions consisting of springs and shock absorbers are installed on each axle of a car, and the springs absorb forces such as the vehicle weight and inertia applied to each axle, which vary due to impacts from uneven ground, acceleration/deceleration, cornering, etc. Shock absorbers dampen vibrations caused by changes in applied force.
In a shock absorber that dampens vibrations, a piston with a valve reciprocates inside a cylinder using a rod, and the dynamic pressure resistance generated during this movement converts impact energy into thermal energy.
The cylinder structure of shock absorbers includes a double-cylinder type having a reservoir chamber provided between double cylinders, and a single-cylinder type having a gas chamber (high-pressure nitrogen gas) separated by a free piston.
The rod of the piston sinks into the shock absorber body, and the compressed gas in the reservoir chamber or gas chamber, which is an accumulator, contracts in hydraulic oil by the volumetric expansion of the rod.
The present invention is a fully active suspension that controls vehicle height using an actuator, and a semi-active suspension that controls damping force in real time in response to ever-changing inputs from the road surface.

In order to balance the centrifugal force that acts in the lateral direction when traveling on a curve, bicycles and motorcycles can tilt their bodies toward the inside of the turn to adapt to the resultant force of centrifugal force and gravity.
Cars and ships (excluding tankers, etc.) that cannot tilt their positions have their centers of gravity above the ground or sea surface, which is the contact surface, so when driving around a curve, the centrifugal force causes the body to tilt to the outside of the turn. Since the occupant's body leans in the opposite direction from the inside, it becomes difficult for the occupant to maintain his or her posture, resulting in inconveniences such as motion sickness.
To solve these problems, automobiles have active suspensions that control vehicle height adjustment using hydraulic pressure, but this requires hydraulic equipment such as hydraulic pumps, solenoid valves, and hydraulic piping, as well as electrical control, which increases costs. problems and energy consumption to drive the hydraulic pumps.
Specifically, many active suspensions use electromagnetic valves to control the hydraulic pressure generated by a hydraulic pump, and use the hydraulic cylinder as an actuator to control the vehicle height. Requires complex and long hydraulic piping for discharge and return.
Furthermore, if a hydraulic pump is provided for each axle, four hydraulic pumps with electrical wiring are required, so both have the problem of increased costs due to the hydraulic pumps and complicated hydraulic piping.
Furthermore, hydraulic pressure for vehicle height control must be constantly generated during control, which requires a power source such as a motor to rotate the hydraulic pump, and energy consumption of approximately several kW to rotate the hydraulic pump, which varies depending on the weight of the vehicle. This is a big problem, especially for small cars, as it worsens fuel efficiency.
Therefore, at present, active suspensions are only installed in some luxury cars and not in small cars.

As a conventional active suspension technology, level control is performed by controlling the hydraulic pressure of the hydraulic cylinder 4 and piston 5 using the electro-hydraulic valve 2, and the control of the hydraulic pressure via the hydraulic ­-pneumatic pressure accumulator 28 is performed to control the level of the hydraulic pressure of the tubular flange 8 and the piston 5. There is an active vibration damping method and device (Patent Document 1) that changes the height of the buffer strut of the working chamber cylinder housing 9.
Since the heights of the buffer struts of the tubular flange 8 and the operating chamber cylinder housing 9 are changed hydraulically, a hydraulic pump and hydraulic piping are required, resulting in problems of increased costs and energy consumption for driving the hydraulic pump.

an inner cylinder 2, a piston 6 that is slidably fitted into the inner cylinder 2 and cooperates with it to define first and second oil chambers 8, 10, and a first pipe connected to the first oil chamber 8; A fluid spring chamber consisting of a first auxiliary oil chamber 20 communicating with each other via a passage 30 and a first gas chamber 22 adjacent to the first auxiliary oil chamber 20 via a first free piston 18; a second auxiliary oil chamber 28 that is communicatively connected to the oil chamber 8 via a second pipe line 32; and a second gas chamber 26 that is adjacent to the second auxiliary oil chamber 28 via a second free piston 24. An active suspension unit configured such that each wheel of the vehicle is independently provided with an active suspension unit ( There is Patent Document 2).
Since the hydraulic pump only sends oil to one corresponding hydraulic cylinder, it operates more efficiently with a lower capacity than a conventional pump that sends oil to four cylinders. In addition, since the piping is simple and short, the pressure loss of oil during oil delivery is small, but four sets of hydraulic units (hydraulic pump 34 and motor 36) are required, which increases the cost and consumes energy to drive the hydraulic pump. There is a problem with this.

The hydraulic cylinder 100 is controlled to expand and contract by the output of the driver DR via the hydraulic pump P, and is configured as a double-acting type divided into upper and lower chambers A and B, and the discharge direction, starting and stopping are also controlled by the output of the driver. The hydraulic pump is configured as a forward/reverse type, and the control valve is configured with a pair of electromagnetic proportional pressure control valves 7 and 8 provided in the recirculation passage from the upper and lower chambers of the hydraulic cylinder to the tank T. A pump, a hydraulic cylinder, and an electromagnetic proportional pressure control valve are independently arranged on each wheel, and the electromagnetic proportional pressure control valve controls the pressure in the upper and lower chambers of the hydraulic cylinder to suppress expansion and contraction of the hydraulic cylinder. A control force is generated, and the oil discharged from the hydraulic pump controlled by the output of the driver is selectively supplied to either the upper or lower chamber of the hydraulic cylinder via the check valves 3 and 4, thereby controlling the vehicle. There is an active suspension control device (Patent Document 3) that controls posture.
This is an active suspension control device that eliminates long hydraulic piping and intermittently adjusts control force and controls posture as needed to reduce power loss. It requires four sets of forward and reverse hydraulic pumps and electric motors. Therefore, there are problems of increased cost and energy consumption for driving the hydraulic pump.

A hydraulic actuator is attached to the piston rod of the suspension strut, and this hydraulic actuator is connected to the control valve of the power steering device so that it operates in accordance with the operation of the control valve of the power steering device by the driver's steering wheel operation. There is a suspension device (Patent Document 4) that can inexpensively configure roll behavior in a forward-down mode that improves the passenger's roll feeling when turning while ensuring sufficient responsiveness and does not affect fuel efficiency. .
Vehicle behavior includes rolling, pitching, and yawing, and since it is linked to steering wheel operation, it is possible to deal with rolling during cornering, but it is difficult to deal with pitching and yawing. This requires additional hydraulic piping, which poses the problem of increased costs.
If the elastic characteristics of the shock absorber are set to be stiff in order to reduce rolling of the vehicle body, the dynamic spring characteristics (dynamic elastic characteristics) at the time of minute displacement are too strong, making it difficult to absorb vibrations transmitted from the wheels to the vehicle body. Therefore, there is a problem that the ride becomes uncomfortable. For this reason, there is an active suspension (Patent Document 5) that changes the elasticity during expansion and contraction using a variable damping force damper that is provided between the wheels and the vehicle body and has an orifice that elastically allows expansion and contraction. .
Variable damping force type dampers control the opening degree of the orifice of a rotatable opening/closing plate using a control signal issued from a controller, so a complicated rotation mechanism is required and the damping force control structure is different.

Japanese Unexamined Patent Publication No. 54-55913 Publication of JP-A-6-72126 Publication of JP-A-2000-264034 Publication of JP-A-2003-220814 Jitszenhei 01-098713 publication

Conventional active suspensions require hydraulic pumps and complicated hydraulic piping to control vehicle height using hydraulic actuators for each axle, and there is a problem in energy consumption to drive the hydraulic pumps during operation. If there is only one hydraulic pump, a long back-and-forth hydraulic piping is required, and if a hydraulic pump is installed on each axle, the hydraulic piping is shorter but multiple hydraulic pumps are required, both of which increase cost and complexity. There are problems with hydraulic piping, etc.
Conventional semi-active suspensions require a complex structure to control damping force, resulting in problems with reliability and increased cost.

A first aspect of the present invention is an active suspension in which a suspension 1 constituted by a shock absorber 2 and a spring 13 is provided with an output means on each axle for controlling the vehicle height using an actuator 4 (for example, a hydraulic cylinder). a connecting cover 16 that separates the accumulator 3 for oil volume adjustment through reciprocating motion and connects the shock absorber 2 and the actuator 4; an accumulator communication pipe 56 that communicates with the accumulator 3; and a check valve that connects the shock absorber 2 with the check valve. A shock absorber communication pipe 57 that communicates in the forward and reverse directions via 52 and 53, an actuator communication pipe 55 that communicates with the actuator 4, and a solenoid valve 51 (for example, a 4-port 3-position directional control valve) is provided on each axle, and the control device 6 of the active suspension 1 controls the solenoid valve 51 to control the vehicle height of each axle. It is a device.

According to a second aspect of the present invention, the electromagnetic valve 51 is installed in the connection cover 16, and the shock absorber communication pipe 57, the actuator communication pipe 55, and the accumulator communication pipe 56 are formed inside the connection cover 16. 2. The active suspension device for a vehicle according to item 1.

According to a third aspect of the present invention, both coils (D) and (U) of the electromagnetic valve 51 for raising and lowering the vehicle height of each axle are wired in parallel, and a diode 517 provided in the wire causes positive pressure to be applied to one of the wires. When a voltage is applied to the wiring, only one coil operates, and when a positive voltage is applied to the other side of the wiring, only the other coil operates. 3. The active suspension device for a vehicle according to claim 1, wherein the electromagnetic valve 51 is controlled by switching the pressure.

According to a fourth aspect of the present invention, when the coil (U) for raising the vehicle height of the electromagnetic valve 51 of the active suspension 1 of each axle is energized, the excitation is stopped when the spring 13 is extended, and the coil for lowering the vehicle height is energized. 4. The active suspension device for a vehicle according to claim 1, wherein the excitation is stopped when the spring 13 is compressed when the spring 13 is energized.

According to a fifth aspect of the present invention, in a semi-active suspension P1 that changes the damping force of a suspension constituted by a shock absorber P2 and a spring P13, an accumulator P3 for adjusting the oil amount by reciprocating movement of a rod P23 of the shock absorber P2 is separated, and the shock A connecting cover P16 that connects the accumulator P3 provided on the absorber P2, an accumulator communication pipe P56 that communicates with the shock absorber P2 and the accumulator P3, and the upper and lower parts of the shock absorber P2 are connected directly or with a check valve. A semi-active suspension P1 is provided on each axle, and includes bypasses P58 and P59 that communicate with each other through the bypasses P58 and P59, and a solenoid valve P51 that controls the opening and closing of the bypasses P58 and P59 and/or controls the flow rate, and controls the semi-active suspension P1. This is an active suspension device for a vehicle in which a device P6 controls the electromagnetic valve P51 to control the damping force of the shock absorber P2.

A first aspect of the present invention is an active suspension in which a suspension 1 constituted by a shock absorber 2 and a spring 13 is provided with an output means on each axle for controlling the vehicle height using an actuator 4 (for example, a hydraulic cylinder). a connecting cover 16 that separates the accumulator 3 for oil volume adjustment through reciprocating motion and connects the shock absorber 2 and the actuator 4; an accumulator communication pipe 56 that communicates with the accumulator 3; and a check valve that connects the shock absorber 2 with the check valve. A shock absorber communication pipe 57 that communicates in the forward and reverse directions via 52 and 53, an actuator communication pipe 55 that communicates with the actuator 4, and a solenoid valve 51 (for example, a 4-port 3-position directional control valve) is provided on each axle, and the control device 6 of the active suspension 1 controls the solenoid valve 51 to control the vehicle height of each axle. It is a device.
According to the present invention, the shock absorber 2 is used as a reciprocating hydraulic pump when the vehicle height is raised, eliminating the need for a hydraulic pump and a rotational drive device for the hydraulic pump.Since the hydraulic circuit is independent for each axle, long hydraulic piping is also unnecessary. This reduces costs, improves maintenance, and eliminates the problem of energy consumption for driving hydraulic pumps.

According to a second aspect of the present invention, the electromagnetic valve 51 is installed in the connection cover 16, and the shock absorber communication pipe 57, the actuator communication pipe 55, and the accumulator communication pipe 56 are formed inside the connection cover 16. 2. The active suspension device for a vehicle according to item 1.
Since all the hydraulic circuits of the hydraulic control device 5 are collectively formed by using the connecting cover as a hydraulic manifold block, there is an effect of reducing costs and improving maintainability since no hydraulic piping is required.

According to a third aspect of the present invention, both coils (D) and (U) of the electromagnetic valve 51 for raising and lowering the vehicle height of each axle are wired in parallel, and a diode 517 provided in the wire causes positive pressure to be applied to one of the wires. When a voltage is applied to the wiring, only one coil operates, and when a positive voltage is applied to the other side of the wiring, only the other coil operates. 3. The active suspension device for a vehicle according to claim 1, wherein the electromagnetic valve 51 is controlled by switching the pressure.
In active suspensions, the actuator and shock absorber rods are connected to the vehicle body through swingable connections, so conduction is unstable.Each rod is insulated by a sealing element such as an oil seal, so body grounding is not possible. In this case, grounding by a movable cable and two positive pressure wirings for both coils of the solenoid valve are required, so a total of three flexible cables are required, but with the present invention, two flexible cables are required. It becomes a cable and has a cost reduction effect.

According to a fourth aspect of the present invention, when the coil (U) for raising the vehicle height of the electromagnetic valve 51 of the active suspension 1 of each axle is energized, the excitation is stopped when the spring 13 is extended, and the coil for lowering the vehicle height is energized. 4. The active suspension device for a vehicle according to claim 1, wherein the excitation is stopped when the spring 13 is compressed when the spring 13 is energized.
Since the excitation time of the solenoid valve is reduced, there is an economical effect of reducing power consumption.

According to a fifth aspect of the present invention, in a semi-active suspension P1 that changes the damping force of a suspension constituted by a shock absorber P2 and a spring P13, an accumulator P3 for adjusting the oil amount by reciprocating movement of a rod P23 of the shock absorber P2 is separated, and the shock A connecting cover P16 that connects the accumulator P3 onto the absorber P2, an accumulator communication pipe P56 that communicates with the shock absorber P2 and the accumulator P3, and the upper and lower parts of the shock absorber P2, either directly or through a check valve. A semi-active suspension P1 is provided on each axle, and is composed of bypasses P58 and P59 that communicate with each other, and a solenoid valve P51 that controls the opening and closing of the bypasses P58 and P59 and/or controls the flow rate, and a control device P6 for the semi-active suspension P1. This is an active suspension device for a vehicle that controls the solenoid valve P51 to control the damping force of the shock absorber P2.
The damping force of the shock absorber P2 can be controlled with a simple structure having no moving parts other than the electromagnetic valve P51, resulting in high reliability and low cost.

1 is a diagram showing the active suspension according to claim 1 of the present invention as a single-wheel model; FIG. 2 is a schematic configuration diagram of the active suspension shown in FIG. 1. FIG. FIG. 3 is an explanatory diagram of vehicle height control (shift displacement) by a hydraulic control device of the active suspension shown in FIG. 2; 4 is an explanatory diagram of spring displacement and shift during vehicle height control of the active suspension of FIG. 3. FIG. 1 is a flowchart showing an example of an information processing routine of an active suspension according to the present invention according to a first embodiment. FIG. 3 is an explanatory diagram of vehicle height control during right curve travel in the first embodiment. FIG. 7 is a schematic cross-sectional view of Example 2 corresponding to claim 2 of the present invention. FIG. 5 is a horizontal sectional view of a connecting cover 16s and a solenoid valve 51s of the hydraulic control device 5s of the second embodiment. FIG. 3 is a schematic configuration diagram of the hydraulic control device of FIG. 2 when the electromagnetic valve is divided. 10 is a horizontal sectional view of a hydraulic control device showing an example of the hydraulic circuit of FIG. 9 according to a third embodiment. FIG. 11 is a horizontal cross-sectional view of a hydraulic control device according to a fourth embodiment, showing an example in which the electromagnetic valves of FIG. 10 are arranged one above the other. FIG. 4 is a schematic cross-sectional view of the active suspension according to the fourth embodiment. FIG. 5 is a schematic cross-sectional view of an active suspension in which an actuator is arranged under a connecting cover according to a fifth embodiment. 1 is a schematic configuration diagram showing an example of an embodiment of an active suspension of the present invention. 1 is a schematic configuration diagram of a control device for an active suspension according to the present invention. FIG. 7 is a schematic configuration diagram of a control device corresponding to claim 3 and showing an example of an output means. FIG. 6 is an explanatory diagram of spring displacement and voltage application timing of a solenoid valve in the active suspension according to claim 4; 12 is an example of a flowchart of an information processing routine corresponding to claim 4 of the sixth embodiment. It is a figure which shows the semi-active suspension of Claim 5 of this invention as a single-wheel model. 20 is a schematic configuration diagram of a case A and a case B showing an example of the semi-active suspension shown in FIG. 19. FIG. 20 is a schematic configuration diagram of a case C and a case D showing an example of the semi-active suspension shown in FIG. 19. FIG. 20A is a schematic cross-sectional view showing an example of Case A in FIG. 20(A) in Example 7. FIG. FIG. 8 is a schematic cross-sectional view showing an example of Example 8 in which the bypass tube of Example 7 is placed in the center. It is a figure which shows the active suspension corresponding to Claim 1 (FIG. 1) and Claim 5 (FIG. 19) of this invention as a single-wheel model. 25 is a schematic configuration diagram showing an example of the active suspension shown in FIG. 24. FIG. 26 is a schematic cross-sectional view showing an example of the active suspension of FIG. 25 in Example 9. FIG. FIG. 7 is a horizontal sectional view of the hydraulic control device of the ninth embodiment. FIG. 26 is a schematic cross-sectional view of an active suspension according to a tenth embodiment, which is different from the ninth embodiment (FIG. 26). 1 is a schematic configuration diagram showing an example of an embodiment of an active suspension according to claims 1 and 5 of the present invention. 30 is a flowchart showing an example of an information processing routine of the active suspension of FIG. 29 in Example 11. FIG.

The contents and embodiments of the active suspension device for a vehicle according to the present invention will be described below with reference to the drawings (FIGS. 1 to 29).
A single-axis model of the active suspension for a vehicle according to claim 1 of the present invention is shown in FIG. 1, and a schematic configuration diagram is shown in FIG. Since the hydraulic circuit for each axle is independent, there is no need for long hydraulic piping.
The action of the hydraulic circuit is performed by switching the electromagnetic valve 51, and the action of the hydraulic control will be explained with reference to FIG. 2 when the vehicle height control is stopped, and with FIG. 3 when the vehicle height control is raised or lowered.
The specific hydraulic behavior caused by switching the solenoid valve 51 and the relationship between the vehicle height shift and the spring displacement are explained in FIG. 4, and a flowchart showing an example of the information processing routine of the active suspension of the present invention is shown in FIG. As an example of shift control, FIG. 6 shows an explanatory diagram of the operation of each element when traveling on a right curve.
In response to claim 2 of the present invention, FIG. 7 shows a schematic cross-sectional view of an active suspension in which the connecting cover 16a is used as a hydraulic manifold block, all hydraulic circuits are integrated inside the connecting cover, and no hydraulic piping is required. FIG. 8 shows a horizontal sectional view of the hydraulic control device shown in FIG.
In order to increase the degree of freedom in the arrangement of solenoid valves in the active suspension of the present invention, a hydraulic circuit diagram in which the solenoid valve of the hydraulic control device is divided into two is shown in FIG. 9. Fig. 10 shows a horizontal cross-sectional view of a hydraulic control device (Embodiment 3) in which the hydraulic control device is arranged on both sides of the connecting cover, and furthermore, in order to make the cross-sectional area of the hydraulic control device compact, a hydraulic control device in which solenoid valves are arranged above and below is shown. A horizontal cross-sectional view of the active suspension is shown in FIG. 11, and a schematic cross-sectional view of the active suspension is shown in FIG. 12.
FIG. 13 shows a schematic cross-sectional view of an active suspension in which the actuator is placed under the connection cover to increase the degree of freedom of installation on the vehicle body connection part 11.
A schematic diagram showing an embodiment of the active suspension of the present invention is shown in FIG. 14, and a schematic diagram of the control device 6 is shown in FIG. 15.
In response to claim 3 of the present invention, FIG. 16 shows a schematic configuration diagram in which the wiring for both coils of the electromagnetic valve shown in FIG. 15 are wired in parallel since it is difficult to ground the body.
In accordance with claim 4 of the present invention, when the coil (U) for raising the vehicle height of the active suspension is energized, the excitation is stopped when the spring is extended, and when the coil (U) for lowering the vehicle height is energized, the coil (U) for raising the vehicle height is stopped. An explanatory diagram of power saving control in which excitation is stopped when the spring is compressed is shown in FIG. 17, and as a sixth embodiment of the power saving control, an example of a flowchart added to the information processing routine (FIG. 5) of the first embodiment is shown. is shown in FIG.
Although this invention is different from claim 1, the semi-active suspension P1 that changes the damping force corresponding to claim 5 of the present invention, which has a technical feature of a communication cover provided on the shock absorber, is shown as a single-wheel model. 19.
As examples of hydraulic circuit configurations, Figure 20 shows schematic diagrams of case A in which the damping force of the shock absorber is controlled in four stages and case B in which the damping force is controlled steplessly. FIG. 21 shows a schematic configuration diagram of variable case C and a case that can correspond to claim 1 of the present invention. A schematic cross-sectional view of P1a is shown in FIG.
A single-wheel model of the active suspension AP1 corresponding to the first aspect of the present invention that performs vehicle height control and the fifth aspect of the present invention that controls damping force is shown in FIG. 24, and FIG. 25 is a schematic configuration diagram of an active suspension AP1w that is an example thereof. A schematic sectional view of one example is shown in FIG. 26 as Example 9, and a horizontal sectional view of the hydraulic control device is shown in FIG. 27.
As an example different from Example 9, FIG. 28 shows a schematic cross-sectional view of an active suspension according to Example 10, in which the actuator is placed under the connection cover to increase the degree of freedom of installation on the vehicle body connection portion 11.
As an example of an embodiment corresponding to a general FF vehicle, the front wheels with a large axle load are provided with an active suspension corresponding to claims 1 and 5 of the present invention, and the rear wheels with axle loads that vary greatly depending on the number of passengers, etc. A schematic configuration diagram of a model corresponding to claim 5 of the present invention is shown in FIG. 29, and an example of its control subroutine is shown in FIG. 30 as an 11th embodiment.

FIG. 1 is a diagram showing an active suspension according to claim 1 of the present invention as a single-wheel model.
In an active suspension 1, the suspension is composed of a shock absorber 2 and a spring 13, and an output means for controlling the vehicle height by an actuator 4 is provided on each axle. A connection cover 16 connects the shock absorber 2 and the actuator 4, an accumulator communication pipe 56 that communicates with the accumulator 3, and a forward and reverse connection between the shock absorber 2 and the check valves 52 and 53. Composed of a shock absorber communication pipe 57 that communicates in the direction, an actuator communication pipe 55 that communicates with the actuator 4, and a solenoid valve 51 (for example, a 4-port 3-position directional control valve) that controls opening and closing of all the communication pipes. An active suspension device for a vehicle, characterized in that an output means is provided on each axle, and a control device 6 (not shown) of the active suspension 1 controls the solenoid valve 51 to control the vehicle height of each axle. be.
As can be seen from the single-axis model in FIG. 1, the structure below the connecting cover 16 is a normal suspension, and the actuator 4 is configured in series with it, so the actuator 4 is responsible for the vehicle weight and inertia applied to the axle. The acting force F and its reaction force -F act as action and reaction.
As shown in the hydraulic control device 5 in this figure, when the coil of the solenoid valve 51 is not excited, the spring 13 expands and contracts during driving due to fluctuations in the acting force F, as in the prior art, and this vibration is absorbed into the shock. It is damped by the braking force accompanying the reciprocating movement of the rod 23 of the absorber 2.
Increases and decreases in the hydraulic oil in the shock absorber 2 caused by the reciprocating movement of the rod 23 are transferred to the air chamber of the accumulator 3 via a shock absorber communication pipe 57 equipped with check valves 52 and 53, a solenoid valve 51, and an accumulator communication pipe 56. It is absorbed by the increase or decrease of.
By switching the solenoid valve 51, it is possible to raise the vehicle height (U) and lower the vehicle height (Ⅾ), and the hydraulic power source for this vehicle height control is used to lower the vehicle height (Ⅾ). At this time, the hydraulic fluid in the cylinder 41 of the actuator 4 is pressurized to a level higher than the internal pressure of the accumulator 3 due to the acting force F such as the vehicle weight applied to the axle, so the actuator 4 is actuated by the hydraulic circuit shown in FIG. 3 (1). When oil flows out into the accumulator 3 and the vehicle height increases (U), the shock absorber 2 functions as a reciprocating hydraulic pump by the hydraulic circuit shown in FIG. 3(2). When the vehicle height increases (U), the hydraulic oil of the actuator 4 statically communicates with the shock absorber 2, so as shown in this figure, the cross-sectional area of the rod 23 of the shock absorber 2 is determined by Pascal's principle. (As) and acting force (F) and ((As/Aa)F) corresponding to the cross-sectional area (Aa) of the cylinder 41 of the actuator 4 are generated, and the action of the active suspension 1 (shifting during vehicle height control) is generated. (relationship of spring displacement) will be explained with reference to FIG.
In this way, the active suspension of the present invention uses the shock absorber as if it were a reciprocating hydraulic pump, so the conventional hydraulic pump and its rotational drive device are not required, and the hydraulic circuit is connected to each axle as shown in this figure. Since it is completed independently, there is no need for long hydraulic piping as in conventional technology, resulting in cost reduction and improved maintenance, and there is no need to consume energy to rotate a hydraulic pump.

FIG. 2 is a schematic configuration diagram of the active suspension shown in FIG. 1.
An active suspension 1 equipped with a hydraulic control device 5 is provided on each axle, the shock absorber 2 and the actuator 4 are connected by a connecting cover 16, and by switching the solenoid valve 51, the rod 43 of the actuator 4 expands and contracts to control the vehicle on each axle. A height adjustment is performed, and the shift amount of the vehicle height is measured by a shift sensor 71.
FIG. 2 shows a state in which the vehicle height control is stopped, and no voltage is applied to the coil of the solenoid valve 51. Therefore, the rod 23 of the shock absorber 2 is connected to the vehicle through the axle connection portion 12 to prevent unevenness on the ground while the vehicle is running. The displacement of the spring 13 occurs due to the impact from the engine, or the inertial force caused by acceleration, deceleration, cornering, etc., and the rod 23 of the shock absorber 2 compresses the hydraulic fluid through the throttle valve 24 provided on the piston 22. 24, and the dynamic pressure resistance at this time converts the impact energy into thermal energy, so the temperature of the hydraulic oil rises.
The rod 23 of the shock absorber 2 sinks into the cylinder 21, and the increase and decrease in the hydraulic oil in the cylinder 21 due to the reciprocating movement of the rod 23 is absorbed by the accumulator 3 via the shock absorber communication pipe 57, the solenoid valve 51, and the accumulator communication pipe 56. .
The solid line arrow in the hydraulic circuit diagram is the movement direction of the hydraulic fluid when the spring 13 is compressed and the spring displacement is in the (-) direction, and the broken line arrow in the hydraulic circuit is the direction in which the spring 13 is expanded and the spring displacement is Indicates the direction of movement of hydraulic oil when displacement is in the (+) direction.
For both spring displacement and shift displacement, the (+) direction is the direction in which the vehicle height increases, and the (-) direction is the direction in which the vehicle height decreases.
Details of vehicle height control by switching the hydraulic circuit of the solenoid valve 51 (4-port 3-position directional control valve) will be explained with reference to FIG.

FIG. 3 is an explanatory diagram of vehicle height control (shift displacement) by the hydraulic control device 5 of the active suspension 1 shown in FIG.
The upper figure (1) is a hydraulic circuit diagram when the vehicle height is lowered by exciting the lowering coil (D) of the solenoid valve 51, which is a 4-port 3-position directional control valve for controlling the vehicle height. It is a hydraulic circuit diagram when the vehicle height is being raised by exciting the raising coil (U) of the solenoid valve 51.
Similarly to FIG. 2, the solid line arrow in the hydraulic circuit diagram is the movement direction of the hydraulic fluid when the spring 13 is compressed and the spring displacement is in the (-) direction, and the dashed line arrow in the hydraulic circuit is 13 shows the movement direction of the hydraulic oil when the spring is expanded and the spring displacement is in the (+) direction.
In the upper diagram (1) of the figure, the coil (D) of the electromagnetic valve 51 is excited by the output from the control device 6 (not shown), and the hydraulic circuit is switched to lowering control of vehicle height control.
The pressure of the hydraulic oil in the cylinder 41 of the actuator 4 varies depending on the acting force F, but it is usually higher than the internal pressure of the non-monocylindrical accumulator 3, so as shown by the solid and broken line arrows, the hydraulic oil in the actuator 4 is , the actuator communication pipe 55, the solenoid valve 51, the check valve 53 and check valve 52 of the shock absorber communication pipe 57, the solenoid valve 51, and the accumulator communication pipe 56, so that the actuator 4 moves continuously to the accumulator 3. As the hydraulic oil decreases, the shift displacement moves in the (-) direction and the vehicle height continuously decreases.
During the lowering, when the rod 23 of the shock absorber 2 is pushed into the cylinder 21, the spring 13 is compressed and the spring displacement is displaced in the (-) direction. The hydraulic oil is sent to the accumulator 3 via the check valve 52 of the shock absorber communication pipe 57, the solenoid valve 51, and the accumulator communication pipe 56, so the hydraulic oil that does not contribute to lowering the vehicle height is routed through the common oil path. , the lowering speed of vehicle height control decreases slightly.
When the rod 23 of the shock absorber 2 is extended from the cylinder 21, the spring 13 is extended and the spring displacement is displaced in the (+) direction. is supplied with a part of the hydraulic oil sent from the actuator 4 and passed through the actuator communication pipe 55, the solenoid valve 51, and the check valve 53 of the shock absorber communication pipe 57, so that the hydraulic oil from the actuator 4 is The outflow of the vehicle is promoted, and the descending speed of the vehicle height control is slightly increased. In this way, although the lowering speed changes somewhat due to the expansion and contraction of the rod 23 of the shock absorber 2, the vehicle height continues to lower, so it can be lowered at any timing, including when the own vehicle is stopped.
In the lower diagram (2) of the figure, the lift coil (U) of the electromagnetic valve 51 is excited by the output from the control device 6 (not shown), and the hydraulic circuit is switched to the lift control of the vehicle height control.
When the spring 13 is compressed, the spring displacement moves in the (-) direction, so the hydraulic oil sent out by pressurizing the hydraulic oil by pushing the rod 23 of the shock absorber 2 into the cylinder 21 moves as indicated by the solid line arrow in the figure. As shown, since it is sent to the actuator 4 via the check valve 52 of the shock absorber communication pipe 57, the electromagnetic valve 51, and the actuator communication pipe 55, the vehicle height increases when the spring 13 is compressed.
When the spring 13 is extended, the spring displacement moves in the (+) direction, so the pressure of the hydraulic oil is reduced by pulling out the rod 23 of the shock absorber 2 from the cylinder 21, and as shown by the broken line arrow in the figure, the spring is displaced from the accumulator 3. Since hydraulic oil is replenished via the accumulator communication pipe 56, the solenoid valve 51, and the check valve 53 of the shock absorber communication pipe 57, the upward movement is stopped when the spring 13 is extended. The vehicle height will be maintained.
Therefore, the active suspension 1 pressurizes the hydraulic oil and raises the vehicle height by the reciprocating movement of the rod 23 of the shock absorber 2 caused by vibrations from the road surface, etc., so that the shock absorber 2 that expands and contracts acts as if it were a reciprocating hydraulic pump. The vehicle height control is raised intermittently.

FIG. 4 is an explanatory diagram of spring displacement and shift during vehicle height control of the active suspension 1 of FIG. 3.
The hydraulic circuit diagram in the schematic configuration diagram above is when the shift is stopped (same as Figure 2), and the hydraulic circuit diagram when the vehicle height is lowered (D) in the center is the same as Figure 3 (1), so it is omitted. However, since the hydraulic circuit diagram at the right end (U) when the vehicle height is raised is the same as that in FIG. 3(2), it is omitted.
The actuator 4 is shown at the center value and shift end of the vehicle height control, and the arrows of each hydraulic circuit are such that the solid line indicates when the spring 13 is compressed, and the broken line indicates the movement direction of the hydraulic oil when the spring 13 is expanded.
Each item of the time chart in the figure below shows, from the top, the shift position, spring displacement, and voltage application state of each coil (down (D), up (U)) of the solenoid valve 51, and the horizontal axis is the time axis.
As shown in the time chart below, while the vehicle is running, the spring 13 expands and contracts due to constantly changing inputs from the road surface along the time axis, causing spring displacement. Specifically, road surface conditions such as uneven road surfaces, periodic vibrations caused by axles including tires, superelevation (cant), and rolling, pitching, and yawing due to inertial forces such as centrifugal force at curves. As a result, various vibrations with different amplitudes and periods occur, and the spring 13 of the shock absorber 2 is displaced.
In order to damp the vibration, a throttle valve provided on the piston 22 suppresses the displacement.
Similar to FIG. 1, hatching Aa in the schematic configuration diagram in the upper figure is the cross-sectional area of the cylinder 41 of the actuator 4, and hatching As is the cross-sectional area of the rod 23 of the shock absorber 2.
When the vehicle height is lowered (D1) in the time chart below, voltage is applied to the coil (D) of the solenoid valve 51 by the output of the control device 6 (not shown), and the solenoid valve 51 is switched to lowering (D). As explained in (1), the internal force of the cylinder 41 of the actuator 4 due to the acting force such as the vehicle weight applied to each axle is normally higher than the internal pressure of the accumulator 3. As the hydraulic fluid in the actuator 4 decreases, the shift displacement moves in the (-) direction, and the vehicle height continuously decreases.
As explained in FIG. 3(1), when the rod 23 of the shock absorber 2 is pushed into the cylinder 21 while the vehicle height is lowering, the lowering speed decreases a little, and the rod 23 is pushed from the cylinder 21 of the shock absorber 2 to the cylinder 21. During extension, the vehicle height continuously decreases while the descending speed increases slightly.
When the vehicle height reaches the target value, the application of voltage to the coil (D) of the electromagnetic valve 51 is stopped based on the input information from the shift sensor 71, and the lowering of the vehicle height is stopped.
When the vehicle height increases (U1) on the time axis of the time chart in the figure below, voltage is applied to the coil (U) of the solenoid valve 51 by the output of the control device 6 (not shown) to switch the solenoid valve 51, and as shown in FIG. As explained in 2), when the spring 13 is compressed, the spring displacement is in the (-) direction, so the hydraulic oil sent out by pushing the rod 23 of the shock absorber 2 into the cylinder 21 is transferred to the actuator 4. Therefore, when the spring 13 is compressed, the vehicle height increases.
As shown in (U1) in the figure below, when the spring 13 is compressed, only the hydraulic oil acts, so the shift amount (Sa1) due to the spring displacement (Ss1) is (As/Aa) of the spring displacement (Ss1). It's double.
When the spring 13 is extended, the spring displacement is in the (+) direction, so when the pressure of the hydraulic oil is reduced by pulling out the rod 23 of the shock absorber 2 from the cylinder 21, hydraulic oil is replenished from the accumulator 3. When the spring 13 is extended, the vehicle height is maintained and the rise is stopped. Therefore, the vehicle height is intermittently raised by pressurizing the hydraulic oil due to the reciprocating movement of the rod 23 of the shock absorber 2, so that the shock absorber 2 acts as if it were a reciprocating hydraulic pump.
It is a necessary condition that the cross-sectional area (As) of the rod 23 of the shock absorber 2 is smaller than the cross-sectional area (Aa) of the cylinder 41 of the actuator 4, and if the area ratio (As/Aa) is large, the amount of increase in vehicle height will be reduced. If the area ratio (As/Aa) is small, the acting force ((As/Aa) x F) of the rod 23 of the shock absorber 2 will become large, which will inhibit the damping function of the spring 13 when compressed. (As/Aa) is an important design element that influences the performance of the active suspension of the present invention.
The vehicle height is raised intermittently every time the rod 23 expands and contracts, so if the damping force of the shock absorber 2 is too strong, the active suspension of the present invention will not be able to exhibit sufficient performance. It is desirable to set the vibration to be more damped.
When the vehicle height increases, if the internal pressure of the actuator 2 acts on the rod 23 and an excessive braking force is generated, the braking force can be controlled in combination with claim 5 of the present invention.

FIG. 5 is a flowchart showing an example of the information processing routine of the active suspension of the present invention according to the first embodiment.
In the active suspension control device 6 of the present invention shown in FIG. 14, based on input information from the driving state determination sensor 7 and the external environment determination sensor 8, which are input means, Control valve 51.
Specifically, it is determined whether the own vehicle is in a running state based on input information such as the vehicle speed sensor 74 of the running state determination sensor 7 of the input means shown in FIG. 15 (step S010).
Here, if it is determined that the vehicle is not running, the solenoid valves 51 of the active suspensions on all axles are not energized and the process proceeds to RETURN (step S110).
On the other hand, if it is determined that the vehicle is running, the shift displacement is measured by the shift sensor 71 of the active suspension of each axle, and the current vehicle height state is confirmed (step S020).
Next, based on input information from the vehicle speed sensor 74, steering angle sensor 75, and acceleration sensor 76 of the driving state determination sensor 7, as well as the in-vehicle camera 81, LIDAR 82, millimeter wave radar 83, etc. , the road condition and driving condition are determined (step S030).
Based on this judgment of road conditions and driving conditions, the expected driving conditions of the vehicle are analyzed, and the optimal shift displacement amount (target value) for roll, pitch, yaw, etc. of the active suspension of each axle is calculated accordingly. (Step S040).
Specifically, the vehicle speed sensor 74 and acceleration sensor 76 measure the current speed and each acceleration, the accelerator opening sensor and vehicle speed sensor 74 predict the vehicle speed trend, and the steering angle sensor 75, vehicle-mounted camera 81, and LIDAR 82 , predict the radius of curvature of the road in the future using the millimeter wave radar 83, map information, etc., and calculate the centrifugal force, etc. Furthermore, road conditions (inclination, superelevation (cant), etc.) are predicted using an external environment determination sensor 8 such as an on-vehicle camera 81, and an optimal shift displacement amount (target value) of the active suspension of each axle is calculated.
The shift displacement (current value) measured by the shift sensor 71 of the active suspension of each axle in step S020 is compared with the target value of the active suspension of each axle calculated in step S040 (step S050).
Here, it is determined whether the difference between the (current value) and (target value) of the shift displacement of the active suspension of each axle is equal to or less than a specified value (error level, etc.) (step S060).
Here, if the difference between the shift displacement (current value) and (target value) of the active suspension of each axle is less than a specified value (error level, etc.), the solenoid valve 51 of the active suspension of the relevant axle is not energized. (Step S0100), the process proceeds to RETURN.
On the other hand, if the difference between the (current value) and (target value) of the shift displacement of the active suspension of each axle is greater than the specified value (error level, etc.), the difference between the (current value) of the shift displacement of the active suspension of each axle and the (target value) If the comparison of (target values) is (target value>current value), the coil (U) of the electromagnetic valve 51 of the active suspension of the axle is excited (step S080), and the process proceeds to RETURN (step S070).
On the other hand, if the comparison between (current value) and (target value) of the shift displacement of the active suspension of each axle is (target value < current value), the coil (D) of the solenoid valve 51 of the active suspension of the relevant axle is Excite (step S090) and proceed to RETURN.
The vehicle height of each axle is controlled according to the above information processing routine.
The flowchart of FIG. 5 is repeatedly executed by the active suspension control device 6 while the own vehicle is driving.

FIG. 6 is an explanatory diagram of vehicle height control when traveling on a right curve according to the first embodiment.
The upper diagram of FIG. 6 is a schematic plan view when the own vehicle 10 is running on a right curve, and the rear view of the own vehicle 10 in each radial direction is the entrance of the curve (C1), the middle of the curve (C2), and the end of the curve. At the exit (C3), when the shift control of the active suspension of the present invention is OFF and ON, the attitude of the own vehicle is improved by turning on the vehicle height control as shown by the arrow.
The lower diagram of FIG. 6 is a time chart showing the operating status of each element in which the control device 6 shown in FIG. 15 shifts and controls the axle on the right side of the front wheel (1FR) in the schematic configuration diagram shown in FIG. 14 when traveling on a right curve. It is.
Items for each element are, from the top, shift position, spring displacement, voltage application state of the ascending coil (U) and descending coil (D) of the solenoid valve 51, steering angle sensor 75 for steering wheel operation, lateral acceleration such as centrifugal force. First, just before entering the curve from the straight road shown in the lower left of the above diagram, the steering wheel operation starts in the right direction to turn, and the time chart of the steering angle sensor 75 indicates that the low setting angle (TL) is measured by the sensor. ), the information processing routine shown in the flowchart in FIG. value, the coil (D) of the solenoid valve 51 of the axle (1FR) is excited, and control to lower the vehicle height of the axle (1FR) is started.
As explained in FIG. 4, the hydraulic oil in the actuator 4 continuously moves to the accumulator 3 via the solenoid valve 51, the accumulator communication pipe 56, etc., so when the hydraulic oil in the actuator 4 decreases, the shift The vehicle height is continuously lowered by moving in the (-) direction of displacement.
However, as explained in FIG. 4, in the vehicle height lowering control, when the rod 23 of the shock absorber 2 is extended, the spring 13 is extended, the lowering speed of the vehicle height control is slightly increased, and the rod 23 of the shock absorber 2 is extended. When the spring 13 is pushed in, the spring 13 is compressed and the spring displacement is displaced in the (-) direction, so the hydraulic oil sent out by pressurizing the hydraulic oil of the shock absorber 2 is sent to the accumulator 3, so that the vehicle height decreases. Since non-contributing hydraulic oil passes through the common oil passage, the lowering speed for vehicle height control is slightly lowered, so the lowering speed varies depending on the displacement of the spring 13.
Next, when the high set angle (Th) is exceeded in the time chart of the steering angle sensor 75, the target value Sh2 of the shift displacement is estimated, compared with the measured value of the shift displacement, and since the target value < the measured value, the axle The coil (D) of the solenoid valve 51 of (1FR) continues to be energized, and the control to lower the vehicle height of the axle (1FR) continues.
After trial calculation of the target value Sh2 of the shift displacement, when the measured value of the shift reaches the target value, the excitation of the coil (D) of the solenoid valve 51 is stopped, and the lowering of the vehicle height is stopped.
In the time chart of the steering angle sensor 75, after calculating the target value Sh2 of the shift displacement, the target value Sh3 is calculated every predetermined time (t) seconds, and the vehicle height control is continued in the above procedure.
After the middle of the curve (C2) in the schematic plan view, as explained in FIG. When the spring 13 is extended, the vehicle height is maintained, so the vehicle rises intermittently.
Although the operating principle of the hydraulic pressure differs when the vehicle height is lowered and raised, the algorithm for controlling the vehicle height is the same as that for lowering the vehicle height, so a description thereof will be omitted.
In FIG. 6, in order to facilitate the explanation of vehicle height control, the predetermined time (t) is made long, the damping control is weakened, and the damping is explained as braking close to damped vibration.
If the lateral acceleration cannot be measured by the acceleration sensor 76, there are methods such as estimating the radius of the curve and using the vehicle speed sensor 74 to estimate the centrifugal force.
It is desirable that the time chart of lateral acceleration and the time chart of shift displacement are essentially synchronized. In this figure of the first embodiment, the shift displacement is controlled with a delay, but by using map information and the external environment determination sensor 8 such as the on-vehicle camera 81, course information such as the curve shape of the road and road surface such as superelevation are determined. It is desirable that the active suspension of the present invention be compatible with automatic driving because it is desirable to predict the situation and perform control using more accurate target values.

FIG. 7 is a schematic cross-sectional view of the second embodiment corresponding to claim 2 of the present invention.
The right figure in FIG. 7 is a longitudinal sectional view of the active suspension 1s of the present invention, and the lower left figure is a horizontal sectional view of the connection cover 16s and a hydraulic circuit diagram of the hydraulic control device 5s.
FIG. 7 corresponds to claim 1 and shows an active suspension 1s in which each axle is provided with an output means for controlling the vehicle height using an actuator 4s in which the suspension is composed of a shock absorber 2s and a spring 13s. A connecting cover 16s that separates the accumulator 3s that adjusts the oil amount by reciprocating motion and connects the shock absorber 2s and the actuator 4s, an accumulator communication pipe 56s that communicates with the accumulator 3s, and the shock absorber 2s and check valve 52s. , 53s, a shock absorber communication pipe 57s that communicates in the forward and reverse directions, an actuator communication pipe 55s that communicates with the actuator 4s, and a solenoid valve 51s (4 ports, 3 position directions) that controls opening and closing of all the communication pipes. An active suspension for a vehicle in which an output means consisting of a control valve) is provided on each axle, and a control device 6 (not shown) of the active suspension 1s controls the electromagnetic valve 51s to control the vehicle height of each axle. It is a device.
Furthermore, the connecting cover 16s shown in the right and lower left diagrams of FIG. The vehicle active suspension 1s according to claim 1, wherein the accumulator communication pipe 56s is formed inside the connection cover 16s.
The lower left figure shows that the connection cover 16s is used as a hydraulic manifold block, and all the communication pipes (55s, 56s, 57s) that make up all the hydraulic circuits are collectively formed, so that the hydraulic pressure of the vehicle active suspension system is independent for each axle. Since the piping is complete, there is no need for any hydraulic piping such as hydraulic hoses.
Details of the hydraulic passage using the connecting cover 16s as a hydraulic manifold block will be explained with reference to FIG.
The accumulator 3s of the active suspension 1s in FIG. 7 also adjusts the increase and decrease of the hydraulic oil in accordance with the reciprocating movement of the rod 23s of the shock absorber 2s, as in the conventional case, and also adjusts the evacuation of the hydraulic oil in accordance with the shift control of the actuator 4s. The oil capacity is larger than the accumulator of conventional shock absorbers.
The ring-shaped free piston 32 of the double-tube accumulator 3s formed by the cylinder 41s of the actuator 4s and the accumulator cylinder 31 can be omitted when the active suspension 1s is installed nearly vertically.
The temperature rise in the hydraulic oil mainly occurs in the shock absorber 2s, and most of the heated hydraulic oil frequently moves back and forth between the accumulator 3s and the heat dissipation property of the hydraulic oil is good.
A flexible power cable (not shown) of the electromagnetic valve 51s is connected to the control device 6 (not shown) via a cable carrier (registered trademark) 181 provided between the vehicle body connection portion top 11s and the connection cover 16s.
If the cable bear (registered trademark) 181 has high rigidity, it can also serve as a rotation stopper for the active suspension body including the connecting cover 16s that moves up and down.

FIG. 8 is a horizontal sectional view of the connecting cover 16s and the solenoid valve 51s of the hydraulic control device 5s of the second embodiment.
In FIG. 8, the connecting cover 16s is used as a hydraulic manifold block, and all hydraulic circuits, such as an actuator communication pipe 55s, an accumulator communication pipe 56s, and a shock absorber communication pipe 57s, are collectively formed, so the hydraulic piping other than the connecting cover 16s is By directly attaching the solenoid valve 51s to the connecting cover 16s, there is no need for a sub-plate for the solenoid valve 51s.
As shown in this figure, the vertical communication pipes (55s, 56s, 57s) communicating with the solenoid valve 51s are connected to the shock absorber 2s under the connection cover 16s as shown in FIG. The communication pipe 57s is in communication, and the other actuator communication pipes 55s and accumulator communication pipe 56s are in communication with the actuator 4s and the accumulator 3s located above the connection cover 16s, respectively.
By providing the check valve 52s and the check valve 53s at the passage opening of the shock absorber communication pipe 57s, a compact hydraulic circuit can be formed.
In parallel with the spool 511 of the solenoid valve 51s, by alternately shifting the openings of each communication pipe in a row up and down to form a staggered arrangement, interference between the openings can be avoided, so the opening of each communication pipe can be further increased. By increasing the diameter, the resistance of each communication pipe can be further reduced.
The action of the solenoid valve 51s is that when a voltage is applied as an output signal from the control device 6 (not shown) to the coil 513 (U) or the coil 513 (D), the movable iron core 514 is attracted to the coil side due to excitation, and the spool By sliding 511 to control the opening and closing of each communication pipe, the hydraulic circuit shown in FIG. 3 is switched, and the vehicle height is controlled as shown in FIG. 4.
Although the solenoid valve 51s is a spool type direct-acting type, it may be a solenoid valve of another type.

FIG. 9 is a schematic diagram of the hydraulic control device of FIG. 2 in which the solenoid valve 51 is divided.
The solenoid valve 51 of the 4-port 3-position directional control valve in the schematic configuration diagram of the active suspension 1 of the present invention in FIG. The valve can be made smaller and the freedom of layout can be increased.
When both electromagnetic valves (51wU, 51wD) are OFF, the hydraulic circuit shown in this figure operates as the same hydraulic circuit as shown in FIG. 2 in which the shock absorber 2 and accumulator 3 communicate with each other, and the vehicle height is maintained. When the coil of the solenoid valve 51wU is energized, the hydraulic circuit becomes the same as (2) in Figure 3, so the vehicle height increases.When the coil of the solenoid valve 51wD is excited, the hydraulic circuit becomes the same as (1) in Figure 3. , the vehicle height decreases. The solenoid valves (51wU, 51wD) have 2 positions instead of 3, so there are 2 solenoid valves, but the spool of the solenoid valve is shorter and the number of coils is reduced from 2 to 1, resulting in a smaller size and improved layout. Increased degree of freedom.

FIG. 10 is a horizontal sectional view of a hydraulic control device 5wa according to the third embodiment, showing an example of the hydraulic circuit of FIG.
In this figure, a solenoid valve 51wUa and a solenoid valve 51wDa are arranged point-symmetrically on the left and right sides of a connecting cover 16wa, and the communication pipes (55wU, 56wU, 57wU) and communication pipes (55wD, 56wD, 57wD) of each solenoid valve are arranged symmetrically. The check valves (52wU, 53wD) are similarly arranged point-symmetrically.
The arrangement and piping of the communication pipes (55wU, 56wU, 57wU) of the solenoid valve 51wUa are the same as the communication pipes (55s, 56s, 57s) including the upper check valve (52s) of the solenoid valve 51s in FIG. The communication pipes (55wD, 56wD, 57wD), which are also point symmetrical, have the same arrangement as the communication pipes 55s, 56s, 57s) including the check valve (53s) below the solenoid valve 51s in FIG. .
As can be seen from the horizontal cross-sectional view of this figure, the vertical dimension of the horizontal cross-sectional view can be compressed compared to FIG. 8, so that the degree of freedom in the arrangement of the active suspension 1wa can be increased.
Since the operation of the hydraulic control device 5wa is the same as that of the solenoid valve 51s in FIG. 8, the explanation will be omitted.

FIG. 11 is a horizontal cross-sectional view of a hydraulic control device 5wb according to the fourth embodiment, showing an example in which the solenoid valves of FIG. 10 are arranged one above the other.
In the upper part (U) of this figure, the solenoid valve 51wUa, each communication pipe (55wU, 56wU, 57wU), and check valve 53wU of the third embodiment (Fig. 10) are installed on the connecting cover 16wb, and in the lower part In the lower part (L) of this figure, the solenoid valve 51wDa, each communication pipe (55wD, 56wD, 57wD), and check valve 52wD of the third embodiment (Fig. 10) are rotated 180 degrees with respect to the cylinder axis, and the solenoid valve This is a hydraulic control device 5wb arranged as a valve 51wDb.
Although the connecting cover 16b is vertically longer, the peripheral convex portion of the active suspension 1wb becomes one surface on the left side of the electromagnetic valve in the horizontal cross-sectional view, and the degree of freedom of attachment to the axle can be increased compared to the third embodiment.
The arrangement and operation of the communication pipes of the electromagnetic valves (51wUb, 51wDb) and the check valves (52wUb, 53wDb) are the same as in the third embodiment.

FIG. 12 is a schematic cross-sectional view of the active suspension 1wb of the fourth embodiment.
The left and right drawings in FIG. 12 are longitudinal sectional views of the active suspension 1wb equipped with the hydraulic control device 5wb of the fourth embodiment.
The structure and operation of each element, the shock absorber 2wb, the accumulator 3wb, and the actuator 4wb, are the same as in the second embodiment (FIG. 7), and therefore the description thereof will be omitted.
The cross section (U-U) of the hydraulic control device 5wb is the upper diagram (U) of FIG. 11, and the cross section (DD) of the right diagram is the horizontal cross-section of the upper diagram (U) of FIG.
The upper end of the spring 13w of the active suspension 1wb is provided with an insulator 141w for vibration isolation between it and the rigid spring seat, and the lower end of the spring 13w is provided with a bearing 14 interposed between the spring 13w and the vehicle body connecting portion 12w. Although the torsional stress caused by the expansion and contraction of the insulator 141w can be relieved, the bearing 14 can be omitted if the insulator 141w does not suffer from wear and tear.
A guide column 183 provided on the upper body connecting portion 11w and a guide 184 provided on the upper cover 15w are detent mechanisms during elevation and descent by vehicle height control, and a flexible cable 19 is arranged inside the guide column 183. be able to. These anti-rotation mechanisms, power supply methods, etc. are provided as an example for reference.
The description of the hydraulic circuit of the hydraulic control device 5wb is omitted because it overlaps with FIG. 11.

FIG. 13 is a schematic cross-sectional view of an active suspension 1wf according to a fifth embodiment in which an actuator 4wf is arranged under a connecting cover 16wf.
In this figure, a ring-shaped actuator 4wf is provided on the outside of the shock absorber 2wf under the connecting cover 16wf, and the spring 13wf is raised and lowered, so the solenoid valves (51wUf, 51wDf) are not raised and lowered. No rotation mechanism, movable cable, etc. are required.
Since the shock absorber 2wf does not move up and down, the stroke corresponding to the stroke of the actuator 4wf becomes longer. However, by providing the upper body connecting portion 11wf on the connecting cover 16wf, the upper body connecting portion (11wf) and the lower body connecting portion (12wf) Since the span between the two can be shortened, the structure can be made more compact.
As explained in Fig. 1, when the vehicle height increases (U), the hydraulic fluid of the actuator 4wf statically communicates with the shock absorber 2wf. Acting force (F) and ((Asf/Aaf)F) are generated according to the cross-sectional area (Asf) of the rod 23wf of 2wf and the ring-shaped cross-sectional area (Aaf) of the cylinder 41wf of the actuator 4wf. The action of this active suspension 1wf (relationship between shift and spring displacement during vehicle height control) is the same as that shown in FIG. 4.
The connection structure of the upper vehicle body connection portion 11wf may be a pin structure as shown in this figure or a trunnion type.

FIG. 14 is a schematic configuration diagram showing an example of an embodiment of the active suspension 1 of the present invention.
This figure is a schematic configuration diagram of the active suspensions (1FL, 1FR, 1RL, 1RR) of each axle and the control device 6 provided in a horizontal cross-sectional view of the vehicle 9.
For vehicle 9, the arrow at the top of the drawing is the traveling direction, the upper axle (1FL, 1FR) in the drawing is the front wheel, the lower axle (1RL, 1RR) is the rear wheel, and they are symmetrical (left side: L, right side). :R).
The active suspensions (1FL, 1FR, 1RL, 1RR) of each axle have the same configuration as shown in FIG.
The input section of the control device 6 in the center of this figure consists of an input section (62 to 64), an output section 65, and a control section 61 that controls them. Input from the shift sensor 71 and other sensor signals (7, 8) from the driving state determination sensor 7 and external environment determination sensor 8 are input, and the control unit 61 analyzes the situation based on the input and output. The output unit 65 instructs the output unit 65 to use the calculated results as an output, and the output unit 65 applies a voltage as an output to the coil of each electromagnetic valve 51 of the active suspension (1FL, 1FR, 1RL, 1RR) of each axle. .
A schematic configuration of the control device 6 will be explained with reference to FIG. 15.

FIG. 15 is a schematic configuration diagram of the control device 6 of the active suspension 1 of the present invention.
This figure shows the control device 6 of the active suspension 1 of the present invention shown in FIG. 1RL, 1RR).
The control device 6 includes a control section 61, an input section including a driving state determination section 62, an external environment determination section 63, and a vehicle attitude determination section 64, and a drive section 65 which is an output section.
The driving state determining section 62 of the input section inputs inputs from the driving state determining sensor 7 of the input means, such as a vehicle speed sensor 74, a steering angle sensor 75, and an acceleration sensor 76, to the control section 61. Inputs from an on-vehicle camera 81, a LIDAR 82, a millimeter wave radar 83, etc., which are the external environment determination unit sensor 8 as input means, are input to the control unit 61, and a vehicle attitude determination unit 64 is an output unit provided on each axle. The input from the shift sensor 71 provided in the active suspension (1FL, 1FR, 1RL, 1RR) is input to the control unit 61.
The control section 61 outputs a signal to the drive section 65, which is an output section, based on the input from the input section, etc., and outputs a signal to the drive section 65, which is an output section, and outputs a signal to each electromagnetic suspension of the active suspension (1FL, 1FR, 1RL, 1RR), which is an output means of each axle. A voltage is output to the ascending coil (U) or descending coil (D) of the valve 51 to control the vehicle height.

FIG. 16 is a schematic configuration diagram of a control device 6c that corresponds to claim 3 and shows an example of an output means.
The circuit of the electromagnetic valve 51 of the active suspension 1, which is the output means provided on each axle in the schematic configuration diagram of FIG. 15, and the drive section 65 of the output section of the control device 6c are changed as shown in this figure.
When both coils ((U), (D)) of the electromagnetic valve 51 of each axle are wired in parallel, and positive pressure is applied to one of the wires by a diode 517 provided in the wire, one When only the coil is activated and positive pressure is applied to the other side of the wiring, only the other coil is activated, and the positive pressure and negative pressure of the voltage applied to the wiring are outputted to the output section of the control device 6c. 3. The active suspension device for a vehicle according to claim 1, wherein the electromagnetic valve 51 is controlled by switching a switch 651 of a drive unit 65 (FL, FR, RL, RR).
The electric circuit of the own vehicle is originally connected to the body ground, and it is also possible to wire only the positive pressure side, but in the active suspension 1, it is installed at the upper and lower swingable body connecting parts 11 and 12, respectively. Although the body ground is effective up to each rod of the actuator and shock absorber, the body ground is not connected to the connecting cover 16 via each cylinder due to hydraulic sealing elements such as O-rings, and the spring 13 is Because the insulator 141 is made of an elastic or plastic material such as rubber, silicone, or nylon, a body ground cannot be ensured, so it is necessary to provide a forced ground. In this case, two command lines for each coil and three wires for forced grounding are required.
As shown in this figure, by switching the switch 651 of the drive unit 65 of the control device 6c, the minimum number of wires required for the two coils of the solenoid valve 51 arranged on each axle is two, resulting in low cost. Improved reliability.
Although the switch 651 of the drive unit 65 is illustrated as a contact circuit that is easy to understand, it is preferable to configure it as a non-contact circuit.

FIG. 17 is an explanatory diagram of spring displacement and voltage application timing of a solenoid valve in the active suspension 1FR according to claim 4.
The upper part of this figure is a schematic configuration diagram of the active suspension 1FR used for explanation, and the hydraulic circuit diagram of the hydraulic control device 5 shows the state when the shift is stopped.
Each item of the time chart in the figure below shows, from the top, the shift position, spring displacement, and voltage application state of each coil (down (D), up (U)) of the solenoid valve 51, and the horizontal axis is the time axis.
The behavior of the shift and spring displacement is explained in FIG. 4, so a description thereof will be omitted.
As shown in the time chart in the figure below, in accordance with claim 4, the spring is The excitation is stopped when the spring 13 is compressed, and when the coil (U) for raising the vehicle height is excited (U2), the excitation is stopped when the spring 13 is expanded. This is an active suspension device for vehicles.
As can be seen from the time chart of the coils (U) and (D) of the solenoid valve 51, when the vehicle height is lowered (D2), the coil (D) of the solenoid valve 51 is energized for a shorter time than the set time (ΔtD). When the spring 13 is compressed, the excitation is continued, and similarly, the excitation of the coil (U) of the solenoid valve 51 is continued when the spring 13 is compressed for a shorter time than the set time (ΔtU). In this way, the power saving effect is small during times shorter than the respective set times (ΔtU, ΔtD) during raising and lowering of the vehicle height, so excitation is continued to reduce the burden of electromotive force on the equipment.

FIG. 18 is an example of a flowchart of an information processing routine corresponding to claim 4 according to the sixth embodiment.
This figure is an example of an information processing routine in which control corresponding to claim 4 is added to the information processing routine for active suspension (FIG. 5) corresponding to claim 1 of the present invention.
In this figure, by inserting the information processing routine shown in bold (steps S071 to S074) after step S070 in FIG. 5, it is determined whether the vehicle height control is raised or lowered in step S070, and the It is determined in steps (S072, S074) whether the spring 13 is in a displacement state to stop the movement, and if the half period of the displacement of the spring 13 is longer than each set time (ΔtU, ΔtD), in step (S100), The excitation of the coil of the solenoid valve 51 of the axle is stopped. Therefore, as explained in FIG. 17, when the coil (U) for raising the vehicle height of the electromagnetic valve 51 of the active suspension 1FR of each axle is energized, when the spring 13 is extended, Power-saving control is possible by stopping excitation and stopping excitation when the spring 13 is compressed when the coil (&#8558;) for lowering the vehicle height is excited.

FIG. 19 is a diagram showing the semi-active suspension according to claim 5 of the present invention as a single-wheel model.
Unlike the fully active suspension 1 that performs vehicle height control according to claim 1 (FIG. 1), this figure shows the passive element parameters of the shock absorption force of the shock absorber and the repulsive force after receiving a shock according to claim 5. This is a semi-active suspension P1 that controls.
In a semi-active suspension P1 that changes the damping force of the suspension composed of a shock absorber P2 and a spring P13, an accumulator P3 that adjusts the oil amount by reciprocating the rod P23 of the shock absorber P2 is separated, and is placed above the shock absorber P2. A connecting cover P16 that connects the accumulator P3 provided in A semi-active suspension P1 is provided on each axle, and includes an upper bypass P58, a lower bypass P59, and a solenoid valve P51 that controls the opening/closing of the bypass and/or the flow rate. This is an active suspension device for a vehicle in which a control device P5 that does not control the electromagnetic valve P51 controls the damping force of the shock absorber P2.
It is controlled by a simple solenoid valve P51, and by attaching the solenoid valve P51 to the connecting cover P16 and using the connecting cover P16 as a manifold block, the hydraulic piping can be built into the connecting cover P16, so there is no need for a special and complicated mechanism. Can be made into a simple structure.
The functions and effects of the hydraulic circuit of the solenoid valve P51 will be explained with reference to FIGS. 20 and 21.
As can be seen from the single-axis model in this figure, the configuration in which the accumulator P3 is separated and the connecting cover P16 is provided is the same as that corresponding to claim 1 in FIG. 1, so if both functions and actions are required, Integration is possible as in Embodiment 9 (FIG. 26), and furthermore, as in Embodiment 10 (FIG. 28), a flexible cable is not required and the degree of freedom in installation can be improved.

FIG. 20 is a schematic configuration diagram of a case A and a case B showing an example of the semi-active suspension shown in FIG. 19.
The upper figure (A) of this figure shows the solenoid valve P51 in Fig. 19 divided into two parts, the solenoid valve P51a1 and the solenoid valve P51a2, in order to increase the degree of freedom in the arrangement of the solenoid valve. When the valve is not energized, it is a normal suspension.
When the solenoid valve P51a1 is energized, the check valve P52a causes hydraulic oil whose flow rate is controlled by the throttle valve P54c to flow only from the upper bypass P58a to the lower bypass P59a, so that when the spring P13 is compressed, the piston of the shock absorber P2 is It has the effect of weakening the shock absorbing power of the throttle valve, and as a result, the vehicle height also decreases, albeit slightly.
This effect is achieved by Pascal's principle when the vehicle height increases as explained in FIG. This has the effect of resolving the problem that an acting force ((As/Aa)F) is generated depending on the cross-sectional area (As) of the rod 23 of the shock absorber 2 and the cross-sectional area (Aa) of the cylinder 41 of the actuator 4.
When the solenoid valve P51a2 is energized, it has the effect of weakening the damping force when the shock absorber 2 is compressed and expanded, so it can be used when the shaft load is small due to the number of passengers, or when the temperature of the hydraulic oil is extremely low. I can handle it.
In the lower part (B) of this figure, the damping force of the shock absorber 2 can be controlled steplessly by using the electromagnetic valve P51b as an electromagnetic proportional valve. Although a controller and amplifier are required, the structure is simple and allows stepless control of the damping force.

FIG. 21 is a schematic configuration diagram of a case C and a case D showing an example of the semi-active suspension shown in FIG. 19.
The upper diagram (C) of this figure shows a configuration in which the check valve P52a of FIG. The damping force can be controlled in four stages with a simple configuration: when no solenoid valve is excited, when one solenoid valve is excited, and when both solenoid valves are excited.
The lower diagram (D) in this figure shows a hydraulic control device P5D in which a check valve P53D is provided on the bypass P58a of the solenoid valve 51a2 in FIG. 20(A) in a direction opposite to that of P52a.
When the solenoid valve P51D1 is energized, the hydraulic oil whose flow rate is controlled by the check valve P52D and the throttle valve P54g flows only from the upper bypass P58D to the lower bypass P59D, so that when the spring P13 is compressed, the piston of the shock absorber P2 is This has the effect of weakening the shock absorbing power of the throttle valve, resulting in the vehicle height being lowered, albeit slightly.
Similarly, when P51D2 is energized, the hydraulic oil whose flow rate is controlled by the check valve P53D and the throttle valve P54h flows only from the lower bypass P59D to the upper bypass P58D. It has the effect of weakening the shock absorption ability of the valve, and as a result, it has the effect of raising the vehicle height, albeit slightly.
Further, by energizing the solenoid valves P51D1 and P51D2, the damping force of the shock absorber P2 can be reduced.
In the eighth embodiment (FIG. 26) or the tenth embodiment (FIG. 28) corresponding to claims 1 and 5, the hydraulic control device P5D shown in the figure (D) below further has the following characteristics: when the solenoid valve P51D1 is energized, As explained in FIG. 1, the above-mentioned action is an acting force corresponding to the cross-sectional area (As) of the rod 23 of the shock absorber 2 and the cross-sectional area (Aa) of the cylinder 41 of the actuator 4, which occurs when the vehicle height increases. It has the effect of canceling out ((As/Aa)F).
The four types of schematic configuration diagrams of Examples A to D showing an example of the semi-active suspension in FIG. As for electromagnetic valves, since there is no stable hydraulic pressure source, a pilot type is inappropriate, so a direct acting type is preferable, and a poppet type is also not preferable, since the primary and secondary sides of the hydraulic pressure are switched.

FIG. 22 is a schematic cross-sectional view showing an example of case A in FIG. 20(A) in Example 7.
This figure shows an example of FIG. 20(A) in which the solenoid valve P51 of FIG. 19 corresponding to claim 5 is divided into two, a solenoid valve P51a1 and a solenoid valve P51a2, in order to increase the degree of freedom in the arrangement of the solenoid valve. It is a schematic sectional view.
This figure shows a semi-active suspension P1a that controls the damping force of a suspension composed of a shock absorber P2 and a spring P13, in which an accumulator P3 for adjusting the oil amount by the reciprocating movement of a rod P23 of the shock absorber P2 is separated, and the shock absorber A connecting cover P16 that connects the accumulator P3 provided on P2, an accumulator communication pipe P56 that communicates with the shock absorber P2 and the accumulator P3, and a bypass that communicates the upper and lower parts of the cylinder P21 of the shock absorber P2. An upper bypass P58a that communicates via a check valve P52a, a lower bypass P59a that communicates via throttle valves P54c and P54D, and solenoid valves P51a1 and P51a2 that control the opening and closing of the bypass and/or control the flow rate. A semi-active suspension P1a is provided on each axle, and a control device P6 (not shown) of the semi-active suspension P1a controls the electromagnetic valves (P51a1, P51a2) to control the damping force of the shock absorber P2. FIG. 3 is a schematic cross-sectional view of the suspension device.
In FIG. 20(A), the upper vehicle body connecting portion P11 is shown in a clevis shape, but in this figure, a trunnion shape is also shown as an option.
The operation is the same as the explanation of FIG. 20, so it will be omitted.

FIG. 23 is a schematic sectional view showing an example of Example 8 in which the bypass tube of Example 7 is changed to the center.
The bypass tube P28 provided on the outer periphery of the shock absorber P2 of the seventh embodiment is, in this figure, provided in the center and inserted into the oil chamber provided in the rod 23b of the shock absorber P2b, so restrictions on the installation of the shock absorber P2b are relaxed. However, since the arrangement of the lower bypass P59a is limited to the center of the connecting cover 16b, the degree of freedom in arrangement of the hydraulic circuit is reduced.
In the seventh embodiment (Fig. 22), the bypass tube P28 is provided in the space between the inner diameter of the spring P13 and the outer diameter of the shock absorber P2, which limits the outer diameter of the shock absorber P2. By providing the tube P28b in the center, the effective diameter of the shock absorber P2b can be increased, resulting in a compact semi-active suspension P1b that can exert a strong damping force.

FIG. 24 is a diagram showing an active suspension AP1 corresponding to claims 1 (FIG. 1) and 5 (FIG. 19) of the present invention as a single-wheel model.
This figure shows an active suspension AP1 in which the hydraulic circuit of the hydraulic control device P5 of the semi-active suspension P1 of the fifth aspect of the present invention shown in FIG. 19 is combined with the active suspension 1 of the first aspect of the present invention shown in FIG. It is a figure showing as a single wheel model.
As can be seen from the figure, the hydraulic control device 5 corresponding to claim 1 of the present invention and the hydraulic control device P5 corresponding to claim 5 of the present invention, which are independent hydraulic circuits, can be operated in their respective hydraulic circuits without interfering with each other. The configuration is maintained.
The operation in this diagram is such that the vehicle height is controlled by the actuator 4, the hydraulic circuit is switched by the solenoid valve 51 to control the raising and lowering of the vehicle height, and the damping force of the shock absorber P2 is controlled by the solenoid valve P51. This damping force control is achieved by reducing the damping force of the shock absorber P2 by the throttle valve P54b provided in the lower bypass P59, and by synchronizing with the rise of the vehicle height control, the acting force generated when the vehicle height rises is reversed. This can be offset by the stop valve P52 and the throttle valve P54a.
The explanation of the configuration in this figure includes the explanation of the configuration and operation (FIG. 24) corresponding to claim 1 of the present invention (FIG. 1) and the configuration of the hydraulic control device P5 corresponding to claim 5 of the present invention (FIG. 19). Since this explanation overlaps with the explanation of the operation (FIG. 19), it will be omitted.

FIG. 25 is a schematic configuration diagram showing an example of the active suspension shown in FIG. 24.
In this figure, the solenoid valve 51 of the hydraulic control device 5 of the active suspension AP1 in FIG. 24 and the solenoid valve P51 of the hydraulic control device P5 of the semi-active suspension are each divided into two parts in order to increase the degree of freedom in arrangement.
The hydraulic circuit of the hydraulic control device 5w in this figure is the same as that shown in FIG. 9, and the hydraulic circuit of the hydraulic control device P5a is the same as that shown in FIG. 20(A).
The basic explanation of this figure is omitted because it overlaps with that corresponding to claim 1 of the present invention (FIG. 1) and that corresponding to claim 5 of the present invention (FIG. 19). In addition, the explanation will overlap with the explanation of the function and operation of (Fig. 24), which is an example of dividing the solenoid valve in (Fig. 1), and (Fig. 20 (A)), which is an example of dividing the solenoid valve in (Fig. 19). omitted.
As can be seen from this figure, in the active suspension AP1w that takes advantage of their respective functions, the hydraulic circuits of the hydraulic control device 5w that controls the vehicle height and the hydraulic control device P5a that controls the damping force do not interfere with each other structurally.
The active suspension AP1w shown in this figure can control the vehicle height up and down using the solenoid valve 51wU and the solenoid valve 51wD, and the solenoid valve P51a2 can reduce the damping force of the shock absorber P2 by the bypass effect of the throttle valve P54D, and the solenoid valve P51a1 Therefore, the acting force (As/Aa) F acting on the rod 23 of the shock absorber P2 due to the vehicle weight when the vehicle height of the hydraulic control device 5w rises as explained in FIG. 1, and the damping force of the throttle valve 24 of the shock absorber P2 are To solve the problem of excessive braking that occurs when a spring 13 is compressed. In this case, the coils of the solenoid valve 51wU and the solenoid valve P51a1 can be connected in parallel and synchronized, or synchronization or asynchronous can be selected as appropriate using the control program.
Although this figure is combined with case A of the semi-active suspension in FIG. 20(A), it can also be combined with other cases B, C, and D.

26 is a schematic cross-sectional view showing an example of the active suspension of FIG. 25 in Example 8.
This figure shows a schematic structure in which the single-axis model of the active suspension AP1 shown in FIG. 24 corresponding to claims 1 (FIG. 1) and 5 (FIG. 19) of the present invention is divided into two parts with the solenoid valve shown in FIG. 25. It is a schematic sectional view of active suspension AP1wt which shows an example of active suspension AP1w of a figure.
Each component in this figure is a hydraulic control device 5wt that controls the vehicle height, which controls an accumulator 3t and an actuator 4t provided on the upper part of a connecting cover 16t, and the structure is the same as that of the second embodiment (FIG. 7). The structure of the shock absorber P2t provided at the lower part of the connecting cover 16t, whose damping force is controlled by the hydraulic control device P5t, is the same as that in the seventh embodiment (FIG. 22). The two solenoid valves arranged above and below each hydraulic control device (5wt, P5t) are arranged in the same manner as in the fourth embodiment (FIGS. 11 and 12).
In the second embodiment (Fig. 7), a cable bear (registered trademark) 181 for power supply and rotation prevention is provided on the connecting cover 16s, but this figure shows a compact link mechanism consisting of an upper arm 186 and a lower arm 187. be.
In the connecting cover 16Pt, the communication pipes that are the hydraulic circuits of the hydraulic control device 5wt of the active suspension AP1wt and the hydraulic control device P5t of the semi-active suspension are integrated into the connecting cover 16t as a hydraulic manifold block. No hydraulic piping is required, and as can be seen from this figure, the active suspension AP1wt has a simple structure in which the hydraulic circuit is completed at each axle.
The outline of these hydraulic circuits will be explained with reference to FIG. 27, which is a sectional view of the cross section (PU-PU) and the cross section (PD-PD) of this figure.
Descriptions of each component, function, etc. will be omitted since they overlap with the descriptions of the respective cited drawings.

FIG. 27 is a horizontal sectional view of the hydraulic control device of the eighth embodiment (FIG. 26).
The upper view (PU) of the hydraulic control device 5wt of the active suspension AP1wt and the hydraulic control device P5t of the semi-active suspension shown in FIG. 26 is the upper horizontal cross section (PU-PU), and the lower view (PL ) is a horizontal sectional view of the lower horizontal section (PL-PL).
As can be seen from FIG. 26, the left side of each cross-sectional view is the hydraulic control device 5wt of the active suspension AP1wt, the right side of each cross-sectional view is a cross-sectional view of the hydraulic control device P5t of the semi-active suspension, and each hydraulic control device ( 5wt, P5t) has solenoid valves arranged in two stages, upper and lower.
The hydraulic control device 5wt of the left active suspension in each cross-sectional view (PU) and (PL) of this figure is the same as the cross-sectional view of Example 4 (FIG. 11), and explanations of the functions of the hydraulic circuit, etc. are omitted. do. Similarly, the hydraulic control device P5t of the semi-active suspension on the right side in each of the cross-sectional views (PU) and (PL) in this figure is one in which the solenoid valves of Embodiment 7 (FIG. 22) are arranged in two stages, upper and lower. The hydraulic circuit is the same as in case A shown in FIG. 20(A).
As shown in this figure, the connecting cover P16t is used as a hydraulic manifold block, and the communication pipes that are the hydraulic circuits of the hydraulic control device 5wt of the active suspension AP1wt and the hydraulic control device P5t of the semi-active suspension are integrated. The active suspension AP1wt eliminates the need for conventional tubular hydraulic piping and completes the hydraulic circuit at each axle with a simple structure.
As described above, the eighth embodiment is an active suspension AP1wt with a simple and compact structure, which has the functions of an active suspension that controls the vehicle height and a semi-active suspension that controls the damping force of the shock absorber.

FIG. 28 is a schematic cross-sectional view of an active suspension AP1wg according to a tenth embodiment, which is different from the ninth embodiment (FIG. 26).
This figure shows a schematic structure in which the single-axis model of the active suspension AP1 shown in FIG. 24 corresponding to claims 1 (FIG. 1) and 5 (FIG. 19) of the present invention is divided into two parts with the solenoid valve shown in FIG. 25. FIG. 7 is a schematic cross-sectional view of an active suspension AP1wg showing an example different from the ninth embodiment of the active suspension AP1w shown in the figure.
Each component in this figure is controlled by a hydraulic control device 5wg, an accumulator 3wg on the upper part of the coupling cover 16g, a shock absorber P2g on the lower part of the coupling cover 16g, and an actuator 4wg provided on the outer periphery of the embodiment 5 ( It has the same structure as Fig. 13).
The shock absorber P2g provided at the lower part of the connecting cover 16g, which is controlled by the hydraulic control device P5g, has the same structure as in Example 8 (FIG. 23), and two solenoid valves are arranged one above the other.
In the vehicle height control by the actuator 4wg shown in the figure, only the spring P13g moves up and down, so the connection cover 16g of the active suspension AP1wg neither moves up and down nor rotates.
Therefore, in this figure, the upper arm 186 for power supply and anti-rotation of the eighth embodiment (FIG. 26) is connected to the upper arm 186 for power supply and rotation prevention in the eighth embodiment (FIG. The link mechanism consisting of the lower part 187 and the flexible cable of the electromagnetic valve are no longer required, and the total length of the active suspension AP1wg can be shortened, so the degree of freedom in installation on each axle is increased.

FIG. 29 is a schematic configuration diagram showing an example of an embodiment of an active suspension according to claims 1 and 5 of the present invention.
This figure is a schematic configuration diagram of vehicle P9, which is a front-wheel drive vehicle (front engine/front drive). The rear wheels are fully active suspensions (1FLk, 1FRk) that can control the damping force, and the rear wheels are semi-active suspensions (P1RL, P1RR) that can control the damping force. It is symmetrical.
FF cars drive the front wheels with an engine located at the front of the car body, and the driving wheels and steering wheels are the same, and they are completed by the bonnet, so they can create a spacious interior, so they are widely used in everything from compact cars to minivans. This is the mainstream drive method.
It is also possible to use active suspension for all axles, which can control the vehicle height and damping force in the same way as the front wheels, but this would complicate the control and increase costs.
In FF vehicles, the front and rear weight distribution is generally around 60:40, and the axle load on the front wheels is large, so it is possible to control the left and right and front and rear vehicle heights to some extent just by controlling the vehicle height of the front wheels.
When the rear wheels are empty, the axle load is smaller than the front wheels, but the influence of the variable loads such as cargo and passengers changes more than the front wheels because the distance from the center of gravity to the axle is shorter, so it is necessary to control the damping force. is important.
This diagram (FIG. 29) is an example of a schematic configuration diagram that takes into consideration the characteristics and cost performance of the FF vehicle.
The full active suspensions (1FLk, 1FRk) and the semi-active suspensions (P1RL, P1RR) can be combined in various configurations shown in each embodiment.
As the front wheel active suspension (1FLk, 1FRk), there is the active suspension AP1wt shown in Example 8, and furthermore, the actuator 4wg is provided under the communication cover 16g, and the arrangement of the vehicle body communication part upper part 11 can be selected.This is a compact embodiment. There are 10.
As a rear wheel semi-active suspension (P1RL, P1RR), the hydraulic control device P5D of the example (D) shown in the lower diagram of FIG. Furthermore, the solenoid valve P51D1 can be energized to control the vehicle height to be lowered slightly, and the solenoid valve P51D2 can be energized to control the vehicle height to be raised slightly, so that the attitude control by the front wheels of the vehicle P9 can be supplemented. Can be done.
The active suspension for each axle (1FLk, 1FRk, P1RL, P1RR) has the same configuration as shown in FIGS. It consists of a sensor 71 and/or an axle displacement sensor 72.
The control device 6k in the center of this figure consists of an input section (62k to 64k), an output section 65k, and a control section 61k that controls them.The input section (62k to 64k) includes a shift sensor 71 for each axle. Inputs from the axle displacement sensor 72 and other sensor signals (7k, 8k) from the driving state determination sensor 7k and the external environment determination sensor 8k are input, and the control unit 61k based on each input/output signal. The situation is analyzed and determined, and an output signal is output from the output section 65k.
The output unit 65k applies a voltage as an output to each electromagnetic valve 51 of the active suspension (1FLk, 1FRk, P1RL, P1RR) of each axle and the coil of each electromagnetic valve P51.

FIG. 30 is a flowchart showing an example of an information processing routine of the active suspension of FIG. 29 in the eleventh embodiment.
In the active suspension control device 6k of the present invention shown in FIG. 29, based on the input information from the driving state determination sensor 7k, external environment determination sensor 8k, etc., which are the input means, the electromagnetic force of the active suspension of each axle, which is the output means. The valve 51 and the solenoid valve P51 are controlled by a control device 6k.
Specifically, it is determined whether the own vehicle is in a running state based on input information such as a vehicle speed sensor of the running state determination sensor 7k of the input means (step S510).
Here, if it is determined that the vehicle is not running, the solenoid valves 51k and P51 of the active suspension for all axles are not excited, and the process proceeds to RETURN (step S610).
On the other hand, if it is determined that the vehicle is running, the shift displacement, axle displacement, acceleration, etc. are measured using the inputs of the shift sensor 71, axle displacement sensor 72, acceleration sensor, etc. of the active suspension of each axle, and the current state of the vehicle is measured. The acceleration of the vehicle, the shift position of each axle, and the spring displacement are measured (step S520).
The input information from the shift sensor 71 and the acceleration sensor allows it to be determined whether the posture of the own vehicle and the driving situation are being adapted to the vehicle. For the front wheels, the compression dimension of the spring 13k of each axle is calculated from the input information of the shift sensor 71 and the axle displacement sensor 72, and for the rear wheel, the compression dimension of the spring 13k of each axle is calculated from the input information of the shift sensor 71. The axle load on each axle can be estimated. These average values determine the total weight of the vehicle, including occupants and cargo, and although the distribution ratio to each axle changes from moment to moment due to inertia, etc., by taking these into consideration, it is possible to determine the total weight of the vehicle, occupants, and cargo. The center of gravity position is estimated (S530).
Based on input information from the vehicle speed sensor, steering angle sensor, and acceleration sensor of the driving condition determination sensor 7k, and the vehicle-mounted camera, LIDAR, and millimeter wave radar of the external environment determination sensor 8k, the current and future expected road conditions and driving conditions are determined. A prediction is made (step S540).
Based on this prediction of road and driving conditions, the expected acceleration of the own vehicle is predicted, and the corresponding shift displacement amount (target value) of the active suspension of each axle is optimal for roll, pitch, yaw, etc. Then, a target value for damping control is calculated (step S550).
Specifically, the current acceleration is measured using an acceleration sensor, the driving situation is determined using an accelerator opening sensor, vehicle speed sensor, and steering angle sensor, and the driving situation is determined using an in-vehicle camera, LIDAR, millimeter wave radar, map information, etc. Predict the road conditions in the direction of travel (curve radius, front/rear slope, superelevation (cant), etc.), calculate centrifugal force and other accelerations, and calculate the optimal shift displacement (target value) for the active suspension of each axle. do.
The current measured values of the shift displacement and axle displacement measured by the shift sensor 71 of the active suspension of each axle in step S520 are compared with each target value of the active suspension of each axle calculated in step S550 (S560).
Here, it is determined whether there is a significant difference between the target value and the current measured value of each axle, and if it is determined that there is no significant difference between any of the axles, the process proceeds to RETURN.
On the other hand, if it is determined that there is a significant difference between the target value and the current measured value for each axle, it is first determined whether there is a significant difference for the front wheels (S570).
Here, if it is determined that there is no significant difference between the front wheels, the process advances to step S590.
On the other hand, if it is determined that there is a significant difference in the front wheels, the front wheel vehicle height control solenoid valve 51k and the damping control solenoid valve P51 are controlled to approach the target values (S580), and the process proceeds to step S590.
Next, it is determined whether there is a significant difference between each target value and the current measured value for the rear wheels (S590).
Here, if it is determined that there is a significant difference in the rear wheels, the solenoid valve P51 for damping control and vehicle height control support is controlled to approach the target value (S600), and the process proceeds to RETURN.
Specifically, as a rear wheel semi-active suspension (P1RL, P1RR), the hydraulic control device P5D in the example (D) shown in the lower diagram of FIG. In addition, the vehicle height can be lowered slightly by energizing the solenoid valve P51D1, and the vehicle height can be raised slightly by energizing the solenoid valve P51D2, so the attitude control force of the vehicle P9 can be controlled. It can be supplemented.
On the other hand, if it is determined that there is no significant difference in the rear wheels, the process proceeds to RETURN.
The flowchart shown in FIG. 30 is repeatedly executed as an active suspension subroutine while driving the own vehicle.
The embodiments described above are examples of the present invention, and do not limit the present invention, and can be modified and improved by those skilled in the art.

In the active suspension of the present invention, the connecting cover provided with the electromagnetic valve is a hydraulic manifold block, and the hydraulic action of the shock absorber is used to control the vehicle height, so a hydraulic pump and its driving energy are unnecessary. The semi-active suspension of the present invention can control damping force with a simple structure and is therefore inexpensive and highly reliable. Since both inventions can be combined into a compact unit by sharing a connecting cover, there is a high degree of freedom in installation and can be used in vehicles such as automobiles.

1 Active suspension 1FL 1FR Front active suspension 1RL 1RR Rear active suspension 2 Shock absorber 3 Accumulator 4 Actuator 5 Hydraulic control device 6 Active suspension ECU
7 Running state determination sensor 8 External environment determination sensor 9 Vehicle 10 Own vehicle 11 Upper vehicle body connection portion 12 Lower vehicle body connection portion 13 Spring 14 Bearing 15 Upper cover 16 Connection cover 17 Lower rod cover 18 Guide 19 Flexible cable 20 (shock absorber)
21 Cylinder 22 Piston 23 Rod 24 Throttle valve 25 Oil chamber 30 (accumulator)
31 Accumulator cylinder 32 Free piston 34 Gas chamber 35 Oil chamber 40 (actuator)
41 Cylinder 42 Piston 43 Rod 44 Gas chamber 45 Oil chamber 50 (hydraulic control section)
51 Solenoid valve 52 Check valve (for discharge)
53 Check valve (for inflow)
54 Throttle valve 55 Actuator communication pipe 56 Accumulator communication pipe 57 Shock absorber communication pipe 59 Solenoid valve 60 (active suspension control device)
61 Vehicle attitude control section 62 Traveling state determining section 63 External environment determining section 64 Vehicle attitude determining section 65 Drive section 70 (driving state determining sensor)
71 Shift sensor 72 Wheel displacement sensor 73 Driving mode 74 Vehicle speed sensor 75 Steering angle sensor 76 Acceleration sensor 80 (external environment determination sensor)
81 In-vehicle camera
82 LIDAR
83 Millimeter wave radar 90 (vehicle)
91 Vehicle body
92 Wheel 92FL 92FR Front wheel 92RL 92RR Rear wheel 141 Insulator 181 Cableveyor (registered trademark)
183 Guide column 184 Guide 186 Upper arm 187 Lower arm 511 Spool 512 Spring 513 Coil 514 Movable core 517 Diode 651 Switch P1 Semi-active suspension P2 Shock absorber P3 Accumulator P5 Hydraulic control device P6 Control device P15 Upper cover P16 Connection cover P17 Lower rod cover P21 Cylinder P22 Piston P23 Rod P24 Throttle valve P26 Communication hole P25 Oil chamber P26 Communication hole P27 Bypass tube P28 Bypass oil chamber P31 Accumulator cylinder P32 Free piston P34 Gas chamber P35 Oil chamber P51 Solenoid valve P511 Spool P512 Spring P513 Coil P514 Moving core P517 Diode P52 Check valve (for upper discharge)
P53 Check valve (for upper inflow)
P54 Throttle valve P58 Bypass upper P59 Bypass lower

Claims (5)

In an active suspension, the suspension is composed of a shock absorber and a spring, and each axle is provided with an output means for controlling the vehicle height using an actuator (for example, a hydraulic cylinder).
Separate the accumulator for adjusting the oil amount by reciprocating the rod of the shock absorber,
a connecting cover connecting the shock absorber and the actuator;
an accumulator communication pipe communicating with the accumulator;
a shock absorber communication pipe that communicates with the shock absorber in a forward direction and a reverse direction via a check valve;
an actuator communication pipe communicating with the actuator;
An output means constituted by a solenoid valve for controlling opening and closing of all the communication pipes is provided on each axle, and the solenoid valve is controlled by the active suspension control device to control the vehicle height of each axle. Features: Active suspension system for vehicles. The vehicle according to claim 1, wherein the solenoid valve is installed in the connection cover, and the shock absorber communication pipe, the actuator communication pipe, and the accumulator communication pipe are formed inside the connection cover. active suspension device. If both coils (or piezo elements) of the solenoid valves of each axle are wired in parallel, and positive pressure is applied to one of the wires using a diode installed in the wire, only one coil will operate. , when a positive pressure is applied to the other side of the wiring, only the other coil is activated, and the voltage applied to the wiring is switched between positive pressure and negative pressure to control the solenoid valve. The active suspension device for a vehicle according to claim 1 or 2. When the coil (U) for raising the vehicle height of the solenoid valve of the active suspension of each axle is energized, the excitation is stopped when the spring is extended, and the coil (U) for lowering the vehicle height is energized. 4. The active suspension device for a vehicle according to claim 1, wherein excitation is stopped when the spring is compressed. In semi-active suspension, which changes the damping force of the suspension composed of shock absorbers and springs,
Separate the accumulator for adjusting the oil amount by reciprocating the rod of the shock absorber,
a connection cover that connects the accumulator provided on the shock absorber;
an accumulator communication pipe communicating with the shock absorber and the accumulator;
a bypass that communicates the upper and lower parts of the shock absorber directly or through a check valve;
A semi-active suspension comprising a solenoid valve for controlling opening/closing of the bypass and/or flow rate control is provided on each axle, and a control device for the semi-active suspension controls the solenoid valve to adjust the damping force of the shock absorber. An active suspension device for a vehicle characterized by controlling.

Images