JPH10246274A - Suspension device for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a suspension device for a vehicle attaining the improvement of comfortableness. SOLUTION: A device has a damper device 2, solenoid assembly 20 displaced integrally with a piston rod 5, and magnets 18, 19 displaced integrally with a cylinder 4. According to going toward the intermediate part of a shaft of the solenoid assembly 20 from one and the other end part thereof, the number of arranging solenoids in the solenoid assembly 20 is decreased.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a suspension apparatus for a vehicle that controls or controls relative movement between a sprung member and an unsprung member by using an electromagnetic force generated by a magnet and a solenoid.

[0002]

2. Description of the Related Art Generally, a conventional suspension device is
It has a cylinder filled with hydraulic fluid, a piston rod protruding from the upper end surface of the cylinder so as to be able to advance and retreat, and assembling the lower end of the cylinder to a unsprung member and connecting the upper end of the piston rod to a sprung member. And a damper device that generates a damping force for suppressing the relative movement by a relative movement between the sprung member and the unsprung member. This suspension device
By appropriately setting the magnitude of the damping force generated in the damper device, the characteristics of the suspension device can be set.

[0003] For example, when the damping force is set to be small, a soft suspension apparatus mainly used for high-class vehicles, which mainly responds to microvibrations, can be provided, and the riding comfort can be improved.

[0004] When the damping force is set to be large, for example, a hard suspension device used for a sports type vehicle can be obtained, and the posture of the vehicle can be maintained well and the operability can be improved.

[0005]

However, this conventional suspension system is particularly suitable for use when the damping device has a small damping force, that is, when the suspension system is set to be soft. When the vehicle travels, the relative movement between the sprung member and the unsprung member cannot be sufficiently suppressed, so that a collision with a bound stopper or a collision with a rebound stopper occurs, and the ride comfort of the vehicle may be degraded.

An object of the present invention is to provide a vehicle suspension device that improves the riding comfort of the vehicle.

[0007]

In order to solve the above-mentioned technical problem, the present invention provides a cylinder filled with hydraulic fluid and a protruding / retractable protruding from an upper end surface of the cylinder. And a lower end of the cylinder is assembled to a unsprung member of the vehicle, and an upper end of the piston rod is assembled to a sprung member of the vehicle. A damper device that generates a damping force that suppresses the relative movement by relative movement with a member, and a damper device that is disposed with the relative movement direction as its axis and is displaced integrally with one of the cylinder and the piston rod A solenoid group and an inner or outer peripheral portion of the solenoid group are disposed so as to face each other, and are displaced integrally with the other of the cylinder and the piston rod; A magnet whose length in the moving direction is shorter than the axial length of the solenoid group, and as one goes from one end and the other end of the solenoid group to the middle part of the shaft of the solenoid group, A suspension device for a vehicle is provided in which the number of solenoids in the solenoid group is reduced.

[0008] Preferably, as described in claim 2,
Preferably, the solenoid group is a suspension device disposed coaxially with the damper device on an outer peripheral side of the damper device.

More preferably, as set forth in claim 3, provided on the outer peripheral surface of the solenoid group, the lower end is supported by the outer peripheral surface of the front cylinder, and the upper end is supported by the sprung member. It is desirable to provide a suspension device having an air spring device that has a case that provides a spring action to the relative movement between the sprung member and the unsprung member by air sealed in the case.

According to the first aspect of the present invention, the relative movement between the sprung member and the unsprung member is suppressed by the solenoid group and the magnet, and is largely suppressed when the relative movement between the sprung member and the unsprung member is large. Will do.

According to the second aspect of the present invention, in addition to the function of the first aspect, the size of the suspension device can be reduced.

In the suspension device of the third aspect, in addition to the functions of the first and second aspects, the solenoid group and the magnet are housed in the air spring device.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to embodiments.

(Embodiment 1) FIG. 1 shows a suspension device 1 of the present invention used for a vehicle suspension device.
FIG. As shown in FIG. 1, reference numeral 1 denotes a suspension device, which is disposed between a vehicle body BD as a sprung member and a lower arm LA as a unsprung member.
The suspension device 1 includes a damper device 2 and an air spring device 3.

Since the damper device 2 is a well-known damper device, its detailed description is omitted.
And a piston rod 5 attached to the cylinder 4 so as to be able to advance and retreat in the axial direction (vertical direction in FIG. 1). The cylinder 4 is attached to the lower arm LA via a bush at its lower end. The piston rod 5 extends upward from the upper end surface of the cylinder 4, and is attached to the vehicle body BD at an upper end portion thereof via an upper support 7 fixed to the vehicle body BD with screws 6.

Since the air spring device 3 is also a well-known air spring device, its detailed description is omitted. However, the air spring device 3 is disposed on the outer periphery of the damper device 2 and includes a case 10 comprising an upper case 8 and a lower case 9. Have.

The upper case 8 is supported by the vehicle body BD on the upper surface thereof via an upper support 11 and a support plate 12, and is hermetically fixed to the outer periphery of the upper end of the piston rod 5 via the support plate 12. I have.

The lower case 9 is formed of a diaphragm mainly composed of elastic rubber, and is hermetically fixed on an inner peripheral surface of a lower end of the upper case 8 by a caulking ring at an upper end thereof. The portion is hermetically fixed to the cylinder 2 via a cylindrical member 13 which is hermetically fixed to the outer periphery of the cylinder 2. A support member 14 made of a non-magnetic material is fixed to the upper surface of the cylinder 4, and the support member 14 includes permanent magnets 18 and 19 described below on the outer periphery thereof.

In the air spring device 3, an air chamber 15 is formed on the outer circumference of the cylinder 4 and the piston rod 5 by the case 10. An electrically controlled intake and exhaust device (not shown) is connected to the air chamber 15 via an inlet 16 so that the amount of air in the air chamber 15 is adjusted.

On the lower surface of the support plate 12, a rubber bound stopper 17 is provided. The bound stopper 17 elastically regulates the bound of the vehicle body BD by abutting on the upper surface of the cylinder 4 via the support member 14.

FIG. 2 is an enlarged view of the vicinity of the magnets 18 and 19 in FIG. As shown in FIG. 2, on the outer peripheral portion of the support member 14, an annular first magnet (permanent magnet) 18 located on the vehicle body BD side and an annular second magnet (permanent magnet) 19 located on the lower arm LA side. And are respectively arranged. First
The magnet 18 and the second magnet 19 are disposed at a predetermined distance apart in the axial direction of the damper device 2 (vertical direction in FIG. 2).

The upper end of the first magnet 18 is magnetized to the N pole, and the lower end is magnetized to the S pole. The upper end of the second magnet 19 is S
The pole is magnetized to the pole, and the lower end is magnetized to the N pole.

A solenoid as a solenoid group whose axial direction is the axial direction of the damper device 2 is provided on the outer peripheral side of the damper device 2 and the magnets 18 and 19 so as to face the outer peripheral surface of the magnets 18 and 19. An assembly 20 is provided.

The solenoid assembly 20 is composed of eleven solenoids having the same axial length and the same number of turns.
It has a cylindrical shape as a whole. The eleven solenoids in the solenoid assembly 20 are three upper end solenoids 20a, 20a, 20a located at the upper end of the solenoid assembly 20, and three lower end solenoids 20b, 20b located at the lower end of the solenoid assembly 20, respectively. , 20b, one intermediate solenoid 20c located at the intermediate portion of the shaft of the solenoid assembly 20, and two upper intermediate solenoids 20d, 20d located between the upper solenoid 20a and the intermediate solenoid 20c. Two lower intermediate solenoids 20e, 20e located between the lower end solenoid 20b and the intermediate solenoid 20c are separately provided. The gap between the upper middle solenoid 20d and the upper solenoid 20a is longer than the gap between the upper middle solenoid 20d and the middle solenoid 20c, and the gap between the lower middle solenoid 20e and the lower solenoid 20b. Are the lower middle solenoid 20e and the middle solenoid 2
0c is longer than the gap. In other words, the solenoids in the solenoid assembly 20 are arranged such that the number of the solenoids decreases along the axial direction of the damper device 2 from the upper and lower ends of the solenoid assembly 20 to the middle of the shaft of the solenoid assembly 20. Have been. The solenoid assembly 20 is fixed to the upper case 8.

In the initial state or the neutral state of the suspension device 1 shown in FIG. 2, the first magnet 18 is opposed to the two upper intermediate solenoids 20d, 20d, and the second magnet 19 is connected to the two lower intermediate solenoids. 20
e, 20e, and the gap between the first magnet 18 and the second magnet 19 faces one intermediate solenoid 20c.

The lead wire of each solenoid is taken out of the upper case 8 in an airtight manner, and
It is electrically connected to an electric control device (not shown) provided outside.

Each of the solenoids is controlled by a drive circuit (not shown) in the electric control device so that current is supplied or not supplied, and the direction of the supply is switched. When a current is applied to the solenoid, the magnetic flux passes in the axial direction of the solenoid, that is, in the vertical direction in FIG. When the direction of the current supplied to the solenoid is the forward direction, the magnetic flux passes through the solenoid from bottom to top. That is, the upper part of the solenoid is equivalent to a magnet magnetized to the N pole and the lower part is magnetized to the S pole. Conversely, when the direction of the current supplied to the solenoid is opposite, the magnetic flux passes through the solenoid from top to bottom.
That is, the upper part of the solenoid is equivalent to a magnet magnetized to the S pole and the lower part is magnetized to the N pole.

The axial lengths of the magnets 18 and 19 are set substantially equal to the axial lengths of three solenoids.

By controlling the energization of each of the solenoids, the solenoid assembly 20 and the magnets 18 and 19 can provide an effect of suppressing the relative movement between the cylinder 4 and the piston rod 5, and furthermore, the vehicle body BD and the lower arm LA. For example, regarding the first magnet 18,
In the solenoid assembly 20, the N of the first magnet 18
The solenoid above the solenoid facing the pole end is energized in the reverse direction. As for the second magnet 19,
The N of the second magnet 19 in the solenoid assembly 20
Energize the solenoid one step below the solenoid facing the pole end in the forward direction. When the energization of the solenoid of the solenoid assembly 20 is controlled via the drive circuit in this manner, an attractive force is generated between the first magnet 18 and the solenoid energized with respect to the first magnet 18, and the second magnet 19 and the An attraction force is also generated between the second magnet 19 and the energized solenoid. Therefore, the magnets 1 and 19 are attracted by the energized solenoids and the magnets 18 and 19.
8, 19 try to be kept in that position. That is, an effect of suppressing the relative movement between the cylinder 4 and the piston rod 5, and furthermore, the relative movement between the vehicle body BD and the lower arm LA is obtained.

For example, with respect to the first magnet 18, in the solenoid assembly 20, one solenoid above the solenoid facing the N-pole end of the first magnet 18 is energized in the forward direction, and with respect to the second magnet 19, When the solenoid below the solenoid facing the N-pole side end of the second magnet 19 in the solenoid assembly 20 is energized in the opposite direction, the first magnet 18 and the solenoid energized with respect to the first magnet 18 are connected. A repulsive force is generated between them, and a repulsive force is also generated between the second magnet 19 and the solenoid energized with respect to the second magnet 19. Therefore, due to the repulsive force between the energized solenoids and the magnets 18 and 19,
The magnets 18, 19 tend to be kept in that position. That is, the cylinder 4 and the piston rod 5, and thus the body BD
The effect of suppressing the relative movement between the arm and the lower arm LA is obtained.

The above-described intake and exhaust devices are electrically connected to the electric control device, and a steering angle sensor (not shown)
A lateral acceleration sensor (not shown), a vehicle height sensor (not shown), and a vehicle speed sensor (not shown) are electrically connected to each other.
The steering angle sensor detects a rotation angle of a steering wheel (not shown) as a steering wheel angle and outputs a detection signal indicating the steering wheel angle. The lateral acceleration sensor is attached to the vehicle body BD, detects lateral acceleration of the vehicle body BD as lateral acceleration, and outputs a detection signal representing the lateral acceleration. The vehicle height sensor is provided between the vehicle body BD and the lower arm LA, detects the height of the vehicle body BD with respect to the lower arm LA as a vehicle height, and outputs a detection signal indicating the vehicle height. The vehicle speed sensor detects a vehicle speed and outputs a detection signal indicating the vehicle speed. Next, the operation of the suspension device 1 configured as described above will be described with reference to FIGS. 1 and 2 show an initial state of the suspension device 1, that is, a neutral state.

The vehicle height adjustment is performed by executing a vehicle height adjustment program (not shown). The microcomputer of the electric control device executes the vehicle height adjustment program every predetermined short time, and determines whether the vehicle height input from the vehicle height sensor is higher or lower than a predetermined reference vehicle height. The intake and exhaust devices are controlled via a drive circuit in the electric control device based on the determination result. If the detected vehicle height is higher than the reference vehicle height, the exhaust device discharges the air in the air chamber 15 of the air spring device 3 of the suspension device 1. This exhaust reduces the air pressure in the air chamber 15, lowers the upper case 8 and the piston rod 5, and lowers the vehicle body BD. On the other hand, if the detected vehicle height is lower than the reference vehicle height,
The intake device supplies air into the air chamber 15 of the air spring device 3. Due to this intake, the air pressure in the air chamber 15 rises, the upper case 8 and the piston rod 5 rise, and the body BD also rises. As a result, the lower arm LA of the vehicle body BD
Is always kept almost constant.

On the other hand, even if an external force is applied to the vehicle body BD from the road surface, the air spring device 3 in which the air chamber 15 is filled with air,
Since the applied external force is absorbed to reduce the impact on the vehicle body BD, the riding comfort of the vehicle is improved.

While the vehicle is running, for example, input from the road surface,
Even if the vehicle body BD vibrates up and down due to a change in the posture of the vehicle body BD or the like, this vibration is suppressed by the damping force of the damper device 2. In particular, if a damper device having a small damping force is selected, a softer suspension device that responds to microvibration can be obtained, and the riding comfort can be improved on a gravel road with small undulations.

Next, the energization and non-energization control of each solenoid of the solenoid assembly 20 will be described. This control is performed by executing an energization / non-energization control program (not shown). This program is repeatedly executed every predetermined short time, and the energization of each solenoid of the solenoid assembly 20 is controlled based on the detection output of the vehicle height sensor and the like.

While the vehicle is running, for example, input from the road surface,
When relative movement occurs between the vehicle body BD and the lower arm LA due to a change in the posture of the vehicle body BD or the like, the relative movement between the vehicle body BD and the lower arm LA is detected by a vehicle height sensor. Since the relative movement between the vehicle body BD and the lower arm LA is a relative movement between the solenoid assembly 20 and the magnets 18 and 19, the first magnet in the solenoid assembly 20 based on the detection output of the vehicle height sensor. A solenoid located one above the solenoid facing the solenoid 18 and a solenoid located one below the solenoid facing the second magnet 19 can be selected. Therefore, the solenoids selected with respect to the first magnet 18 and the second magnet 19 are energized and controlled as described above, so that the relative movement between the vehicle body BD and the lower arm LA is suppressed so that the solenoid assembly 20 and the magnet 18 are controlled. , 19 work.

In particular, when the vehicle travels on a rugged mountain road or the like, the relative movement between the vehicle body BD and the lower arm LA increases, and in the solenoid assembly 20, the first magnet 18 includes the upper end solenoid 20a and the lower middle solenoid 20e. The second magnet 19 moves around the range of the position, and the lower end solenoid 20b and the upper middle solenoid 20d
Will move around the range where is located.

Here, the damping device 2 generally has a small damping force, that is, a soft suspension device does not sufficiently suppress the relative movement between the vehicle body BD and the lower arm LA. When the lower arm LA moves to the uppermost position with respect to the vehicle body BD due to a large bounce, the cylinder 4 may hit the bound stopper 17 via the support member 14 and a shock may be transmitted to the vehicle body BD.

However, in the present suspension device 1, when the vehicle largely bounces and the lower arm LA moves to the uppermost position with respect to the vehicle body BD, the N pole end of the first magnet 18 is directed toward the upper end solenoid 20a. As a result, the N pole side end of the second magnet 19 moves toward the upper solenoid of the middle solenoid 20c or the lower middle solenoid 20e. Therefore, for the first magnet 18, one of the upper solenoids 20a is selected, and for the second magnet 19, the middle solenoid 2a is selected.
Either 0c or the upper solenoid of the lower middle solenoid 20e is selected. In this case, the distance between the N pole side end of the first magnet 18 and the upper end solenoid 22a and the second
Since the distance between the N-pole end of the magnet 19 and the middle solenoid 20c or the lower middle solenoid 20e is short, an electromagnetic force generated between the selected solenoid and the magnets 18, 19, for example, an attractive force. Becomes stronger. Therefore, it is possible to sufficiently suppress the relative movement between the vehicle body BD and the lower arm LA, and it is possible to eliminate the possibility that the cylinder 4 hits the bound stopper 17 via the support member 14 and transmits an impact to the vehicle body BD. Become.

When the vehicle rebounds greatly and the lower arm LA moves to the lowermost position with respect to the vehicle body BD, the N-pole end of the second magnet 19 moves toward the lower end solenoid 20b. The N pole side end of one magnet 18 is an intermediate solenoid 20c or an upper intermediate solenoid 20d.
Will move toward the lower solenoid. Therefore, for the second magnet 19, one of the lower solenoids 20b is selected, and for the first magnet 18, either the middle solenoid 20c or the upper solenoid of the upper middle solenoid 20d is selected. The second in this case
The distance between the N-pole end of the magnet 19 and the lower end solenoid 22b, and the N-pole end of the first magnet 18 and the middle solenoid 2
0c or the distance to the upper middle solenoid 20d is short, so the selected solenoid and magnet 1
The electromagnetic force, for example, the attraction force generated between the first and second motors 8 and 19 is increased. Therefore, the relative movement between the vehicle body BD and the lower arm LA can be sufficiently suppressed, and the possibility that the cylinder 4 hits a rebound stopper (not shown) and transmits an impact to the vehicle body BD can be eliminated.

That is, the restraining force against the relative movement between the vehicle body BD and the lower arm LA by the solenoid assembly 20 and the magnets 18 and 19 in the suspension device 1 is as follows.
The greater the relative movement, the greater the effect.

The force for suppressing the relative movement between the vehicle body BD and the lower arm LA due to the electromagnetic force between the magnets 18 and 19 and the solenoid assembly 20 is generated between the vehicle body BD and the lower arm LA like the damper device 2. Since the response can be made immediately without being caused by the occurrence of the relative speed, the control responsiveness of the suspension device 1 can be improved.

As described above, according to the suspension device 1 of the present embodiment, particularly when the damping force of the damper device 2 of the suspension device 1 is set to be small so as to cope with minute vibration, the damper device 2 A large relative movement between the vehicle body BD and the lower arm LA, which may not be sufficiently suppressed, can be suppressed by adding an electromagnetic force generated by the solenoid assembly 20 and the magnets 18 and 19 of the suspension device 1. Therefore, it is possible to suppress the contact with the bound stopper 17 and the contact with the rebound stopper.

Further, in the solenoid assembly 20, the number of solenoids can be reduced in the vicinity of the middle portion of the shaft, so that the weight of the suspension device 1 can be reduced and the cost can be reduced. .

Therefore, it is possible to provide a suspension device that improves the riding comfort of the vehicle.

In this embodiment, in the solenoid assembly 20, the positions at which the solenoids are disposed are the upper end, the lower end, the middle, the upper middle, and the lower middle, and the upper end solenoid 20a has three positions. Three for the lower solenoid 20b and one for the middle solenoid 20c.
Two solenoids are provided for the upper middle solenoid 20d and two solenoids are provided for the lower middle solenoid 20e, but it goes without saying that the present invention is not particularly limited to this configuration.

In this embodiment, the solenoid assembly 20 is disposed so as to be displaced integrally with the piston rod 5, and the magnets 18 and 19 are disposed so as to be displaced integrally with the cylinder 4. However, the present invention is not particularly limited to this configuration.
The same operation and effect can be obtained in the suspension apparatus of the present invention in which 0 is disposed so as to be displaced integrally with the cylinder 4 and the magnets 18 and 19 are disposed so as to be displaced integrally with the piston rod 5. .

In this embodiment, the magnets 18 and
The axial length of 19 corresponds to three axial lengths of the solenoid, but it goes without saying that it is not particularly limited to this.

In this embodiment, the case 10
Is composed of an upper case body 8 and a lower case body 9, but it goes without saying that the present invention is not particularly limited to this structure.

[0050]

According to the first aspect of the present invention, particularly in a suspension device in which the damping force of the damper device is set to be small, when the relative movement between the sprung member and the unsprung member is large, the solenoid group and the magnet are connected to each other. Thereby, the relative movement between the sprung member and the unsprung member can be suppressed.

Therefore, it is possible to suppress the contact between the bound stopper and the rebound stopper, and it is possible to provide a suspension device with improved riding comfort.

According to the second aspect of the invention, in addition to the effect of the first aspect of the invention, it is possible to provide a suspension device that makes effective use of space.

According to the third aspect of the invention, in addition to the effects of the first or second aspect of the invention, it becomes possible to maintain good characteristics of the solenoid group and the magnet and to improve durability.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a suspension device 1 according to a first embodiment.

FIG. 2 is an enlarged view of the vicinity of magnets 18 and 19 in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Suspension device 2 Damper device 3 Air spring device 4 Cylinder 5 Piston rod 10 Case 18 First magnet 19 Second magnet 20 Solenoid assembly BD Car body LA Lower arm

Claims (3)

[Claims] 1. A cylinder having a hydraulic fluid sealed therein, a piston rod protruding from an upper end surface of the cylinder so as to be able to advance and retreat, and a lower end portion of the cylinder being assembled to an unsprung member of a vehicle and having a piston rod. And a damper device that generates a damping force that suppresses the relative movement by a relative movement between the sprung member and the unsprung member. A solenoid group that is disposed as the shaft and that is integrally displaced with one of the cylinder and the piston rod; and that is disposed to face an inner peripheral portion or an outer peripheral portion of the solenoid group, and the cylinder and the piston A magnet which is integrally displaced with the other of the piston rods and whose length in the relative movement direction is shorter than the axial length of the solenoid group; A suspension device for a vehicle in which the number of solenoids arranged in the solenoid group is reduced as going from one end and the other end of the solenoid group to an intermediate portion of the shaft of the solenoid group. 2. The vehicle suspension device according to claim 1, wherein the solenoid group is disposed coaxially with the damper device on an outer peripheral side of the damper device. 3. A case provided on an outer peripheral surface of the solenoid group, a lower end of which is supported by an outer peripheral surface of a front cylinder, and an upper end of which is supported by the sprung member. 3. The suspension device for a vehicle according to claim 1, further comprising an air spring device that imparts a spring effect to a relative movement between the sprung member and the unsprung member by air filled in the sprung member.