JP2953674B2 - Suspension device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a suspension device having an electromagnetic actuator.

[0002]

2. Description of the Related Art Conventionally, as a suspension apparatus having an electromagnetic actuator, for example, Japanese Utility Model Laid-Open Publication No. 1-1167.
No. 10 is known.

In this conventional device, a cover formed in a cylindrical shape and fixed to a vehicle body is provided between a vehicle body and wheels, and a piston slidably provided in the cover and attached to a wheel side. A fixed coil and a control coil constituting an electromagnetic actuator are provided in the cover and on the outer periphery of the piston.A position sensor for detecting a relative position of the fixed coil on the piston side is provided on an outer surface of the cover. It is a provided structure.

A control force (electromagnetic attraction / repulsion) is generated in the axial direction of the coil by controlling the direction of current flow and the current to both coils based on the detection signal from the position sensor. Control to keep the vehicle height constant.

[0005]

However, such a conventional suspension apparatus controls the suspension apparatus only by the control force (electromagnetic attraction / repulsion) generated by the electromagnetic actuator as described above. However, there is a limit to the shock absorption capacity, and therefore, depending on the driving conditions of the vehicle, it is not possible to absorb a large shock input,
There is a problem that the suspension unit may be damaged.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has as its object to provide a suspension device capable of preventing a suspension unit from being damaged by a large impact input.

[0007]

According to the present invention, there is provided a suspension unit having a vehicle-side member and a wheel-side member formed so as to be relatively movable , and the vehicle-side member (1) is provided.
And one of the wheel-side member (2) having a gap (1c).
The vehicle body-side member (1) and the wheel side are formed in a heavy cylindrical structure.
The other member with the member (2) is inserted in the gap (1c) in the axial direction.
Is inserted so that it can be displaced relative to
Buffer that changes its volume with the bottom based on relative displacement
A liquid chamber (C1) for the buffer is formed.
Fluid enters and exits due to the change in volume in 1), resulting in damping force
A damping force generating means (1p) for generating
The magnets (1j, 1k) are provided inside and outside with the gap (1c) in between.
The member inserted into the gap (1c) includes the magnet
Coil across the magnetic field formed by (1j, 1k)
(3) is wound, and this coil (3) is axially
Divided into multiple parts, each connected in parallel
And the coil (3) can be energized and short-circuited.
A possible control circuit (6) is provided.
You.

That is, in the suspension device of the present invention,
A suspension unit having a vehicle-side member and a wheel-side member formed so as to be relatively movable; an electromagnetic actuator provided between the two members to generate a control force in a direction of relative movement between the two members; And damping means for generating a damping force by flowing the fluid based on the movement.

[0009]

[Work] When an impact is input to the suspension unit, the fluid flows in the damping means and a damping force is generated in accordance with the relative movement between the vehicle body side member and the wheel side member based on the input. Therefore, the control force of the suspension unit is controlled by the damping force generated by the damping means and the control force including the driving force and the control force generated by the electromagnetic actuator. Further, when a large impact is input to the suspension unit, a damping force is generated in the damping means, so that the suspension unit is prevented from being damaged.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS First, the structure of a suspension device according to a first embodiment of the present invention will be described.

[0011] Figure 1 is a general view showing a suspension device of the first embodiment, in this FIG., S ₁ denotes a suspension unit. The suspension unit S ₁ includes a vehicle body member 1 which is connected to the vehicle body side and a wheel side member 2 which is connected to the wheel side.

The vehicle-body-side member 1 is formed of a magnetic material, and has a cylindrical inner pillar 1a provided at an axial center as shown in the figure.
And a cylindrical outer cylinder 1b having a bottom, and are formed in a double structure having a cylindrical gap 1c therebetween. The inner pillar 1a
In the state where the rod part 1d formed at the top is penetrated through the bottom of the outer cylinder 1b, the tip of the rod part 1d is
e and integrally formed with the outer cylinder 1b. Also,
A substantially lower half of the outer cylinder 1b is bulged inward on the vehicle body side member 1, and an outer permanent magnet 1j is formed on the inner peripheral surface of the bulged portion.
, The lower half of the inner column 1a is bulged outward, and the inner permanent magnet 1k is provided on the outer peripheral surface of the bulged portion, so that the magnetic field forming part 1g in which the gap of the gap 1c is narrowed is provided. Are formed.

The two permanent magnets 1j and 1k are connected to each other as shown in FIG.
As shown in (1), the polar directions of the two permanent magnets 1j and 1k are set so that they are each divided into four in the circumferential direction, and the magnetic field direction is the radial direction at the position sandwiching the circumferential gap 1c. ing. A cylindrical reinforcing permanent magnet 1f is provided on the outer periphery of the rod portion 1d, and is fixed by a fastening force between the rod portion 1d and the bolt member 1e. That is, since the vehicle body side member 1 is formed of a magnetic material,
The permanent magnets 1j and 1k and the reinforcing permanent magnet 1f form a magnetic path A indicated by a dashed line in the figure. In the magnetic field forming portion 1g, a magnetic field B is formed in the radial direction as shown in FIG. Have been. The direction of the magnetic path A is the same as that of each permanent magnet 1.
The polarity differs depending on the directions of the polarities j, 1k, and 1f. In the present embodiment, the polarities are set such that the magnetic path A is formed as illustrated. Further, the magnetic field forming portion 1g and the reinforcing permanent magnet 1
f, the reinforcing coil 1
h is wound. Further, the bolt member 1e
Is for vehicle body mounting.

On the other hand, the wheel-side member 2 is formed in a bottomed cylindrical shape having a bottom at the lower end, and a bolt 2a for mounting to the wheel is provided upright at the lower end. The wheel-side member 2 has its opening end side inserted into the gap 1c from the opening end side of the vehicle body-side member 1 and has a small clearance with the vehicle body-side member 1 on its outer periphery. Coil 3 is wound. This coil 3 has independent first to
Eighth coils 3a to 3h are formed. The coils 3a to 3h and 7c are wound around one bobbin 3k. Further, the fourth coil 3d and the fifth coil 3e
A speed detection coil 7c is wound between the two. Further, in the stroke range of the suspension unit S _1, the length of the magnetic field forming portion 1g so that the state of the speed detection coil 7c is always placed in a magnetic field B is set.

A piston portion 2b is formed at the tip of the wheel-side member 2, and a seal ring 2c is formed on the outer peripheral surface thereof so as to slidably seal the inner peripheral surface of the outer cylinder 1b with the inner peripheral surface.
Is provided. Also, the inner pillar 1 of the vehicle body side member 1
A piston 1m is formed at the distal end of a, and a seal ring 1n for slidably and hydraulically sealing between the inner peripheral surface of the hollow portion 2d of the wheel side member 2 is provided on the outer peripheral surface thereof. I have. Therefore, an upper chamber C ₁ and the lower chamber E ₁ is formed in the suspension unit S _1, and the lower chamber E
With a fluid such as oil is filled in _1, fluid is accommodated to form the air reservoir portion F to the upper in the upper chamber C _1.

The upper chamber C ₁ and the lower chamber E ₁ are
The orifice hole 1p formed in the inner column 1a in the radial direction and the communication hole 1r formed in the axial center of the inner column 1a communicate with each other, so that the fluid flows between the two chambers C ₁ and E _1. It is possible. In addition, on the outer periphery of the middle part of the inner pillar 1a,
A bearing 4 for guiding the sliding of the wheel side member 2 is provided.

The coil 3, the speed detecting coil 7c and the reinforcing coil 1h are connected to a control circuit 6. That is, the control circuit 6 energizes the reinforcing coil 1h so that a magnetic field is generated in the same direction as the magnetic field formed in the vehicle body-side member 1. The control circuit 6 is configured such that the connection state of each of the coils 3a to 3h can be switched in series or in parallel with respect to the coil 3, and the control circuit 6 can be switched between the terminals of the coils 3a to 3h. It is formed so as to be energized or short-circuited, and is configured to connect a variable resistor to these coils 3 at the time of energization and short-circuit.

FIG. 4 is a circuit diagram showing the configuration of the control circuit 6. In this case, the first coil 3a and the second coil 3
Only the part that controls b is shown. This control circuit 6
Is provided with a variable resistor 6a, and the terminals sa, sb, sc, and sd are provided with 0, 1
, The first coil 3a and the second coil 3b are switched between parallel connection and series connection, and both the coils 3a and 3b are short-circuited or both the coils 3a and 3b
, Etc .. By the way,
If short circuit the coil 3, the suspension unit S ₁ is a stroke, that the coil 3 in a direction transverse to the magnetic field B of the magnetic field forming portion 1g moves, induced current is generated in proportion to the coil 3 to the relative velocity, the When the induced current consumes power by the variable resistor 6a, the moving energy is reduced, that is, a damping force is obtained. On the other hand, when the coil 3 was energized driven, by energization in a direction crossing the magnetic field B of the magnetic field forming portion 1g is made, according to the direction the intensity of the current, the driving force in the extension direction of the suspension unit S ₁ is Or a driving force acts in the pressure direction. As described above, the inner and outer permanent magnets 1j and 1k, the reinforcing permanent magnet 1f, and the reinforcing coil 1h constitute an electromagnetic actuator.

[0019]

[Table 1]

By the way, the damping force and the driving force generated as described above (hereinafter, referred to as control force) are applied to the coil 3
Are larger when connected in parallel than when they are connected in series. That is, among the eight coils 3a to 3h, the number of coils crossing the magnetic field forming portion 1g is set to five.
If the length of a~3h was L _C, generated force F _S in the case of the series connection is expressed by Equation 1 below, whereas the generated force F _P when the parallel connection is expressed by Equation 2.

[0021]

[Formula 1]

[0022]

[0023]

[Formula 2]

[0024]

Where B is the magnetic flux density in the magnetic field forming section,
X is the relative speed between the coil and the magnetic field, L is the winding length per coil, and R is the resistance per coil.

Therefore, F _P / F _S = 40 / (25/8)
= 12.8, and in parallel connection, 12.8 of series connection
Double control power is obtained.

[0027] The control circuit 6 performs control based on input from the vehicle height sensor 7a, the acceleration sensor 7b and the speed detection coil 7c, the vehicle height sensor 7a is a vehicle body side member 1 of the suspension unit S ₁ And wheel side member 2
, So that the vehicle height can be detected based on both stroke amounts. The acceleration sensor 7b
Is mounted on the vehicle body to detect the vertical acceleration of the vehicle body, and is provided to determine the vehicle speed in the vertical direction. The speed detection coil 7c is provided to determine the relative speed between the vehicle body side and the wheel side. And
The arithmetic unit of the control circuit 6 performs control to keep the vehicle attitude constant based on the input from the vehicle height sensor 7a, and performs damping force control based on input signals from the acceleration sensor 7b and the speed detection coil 7c. Has become.

The suspension device having the above-described structure is
Provided suspension unit S ₁ between each and the vehicle body of the four wheels of the car, also, a control circuit 6, both sensors 7
a, and 7b and speed detection coil 7c, it is to use provided for each one of the suspension units S _1.

Next, the operation of the first embodiment will be described.

(A) When the suspension unit S ₁ strokes during the stroke of the suspension unit, the vehicle body side member 1
And the wheel-side member 2 move relative to each other, and in the compression stroke, the lower chamber E ₁
Fluid of the inner is distributed to the upper chamber C ₁ side, whereas, the fluid of the upper chamber C ₁ is circulated to the lower chamber E ₁ side in the extension stroke, when this,
As shown in FIG. 5, a damping force having a square characteristic occurs in the orifice hole 1p. Incidentally, when the suspension unit S ₁ is a stroke, although the volume of the upper chamber C ₁ is also increased or decreased in direct proportion to the volume change of the lower chamber E _1, the chambers C _1,
Increment or decrement of the volume of E ₁ is air in the upper chamber C ₁ side air chamber F which is formed is absorbed by compression or expansion.

Further, when the suspension unit S ₁ is the stroke, by the speed detecting coil 7c in a direction crossing the magnetic field B of the magnetic field forming portion 1g is moved, the speed detecting coil 7c of linear characteristic proportional to the relative velocity An induced electromotive force is generated. Note that the relative speed can be detected over the entire stroke by moving the speed detection coil 7c within the range of the magnetic field B of the magnetic field forming unit 1g.

[0032] (b) according to the running condition of the damping force control when the vehicle, in the case of generating the damping force at the portion of the electromagnetic actuator of the suspension unit S ₁ short-circuits the coils 3a to 3h. Then, a damping force (control force) is generated according to the relative speed between the vehicle body side member 1 and the wheel side member 2, that is, in direct proportion to the speed of the coil 3 passing through the magnetic field forming portion 1g.

FIG. 5 shows an example of the damping force characteristic with respect to the piston speed when the connection of the coil 3 is connected in parallel. By arbitrarily selecting the resistance value of the variable resistor 6a,
Any damping force coefficient can be selected. Therefore, when the suspension unit S ₁ is the stroke obtained damping force characteristic shown in FIG. 5 Noto, damping force characteristics indicated by + in Figure 5 is obtained throughout the suspension unit S _1. Therefore, a sufficient damping force can be obtained even in a high piston speed region indicated by hatching in FIG. 5, and the suspension unit S ₁ when a large impact is input is obtained.
Can be prevented from being damaged.

When performing such damping force control, there is no need to energize the coil 3 and no power is consumed. Note that, when the reinforcing coil 1h is energized, the magnetic flux density of the magnetic field B of the magnetic field forming portion 1g increases.
A large damping force (control force) can be obtained, and when no large damping force (control force) is required, power consumption can be saved by canceling energization.

(C) At the time of driving force control When driving force is generated, such as when posture control is performed, the coils 3a to 3h are energized. Then, the axial upward and downward driving force of the suspension unit S ₁ by current flow occurs through the magnetic field B, that is, a force for both members 1 and 2 relative movement occurs,
Attitude control and the like can be performed based on this driving force.

In this case, the direction and strength of the driving force (control force) change depending on the direction of power supply and the electric power.
As shown in the control force characteristic diagram, the driving force can be controlled in the range of S and -S.

Further, when the suspension unit S ₁ is the stroke, since the damping force shown in FIG. 7 of occurs in the suspension unit S _1, to have a width of s to-S attenuation characteristic of FIG. 7 In other words, the characteristic of the driving force can be changed within the range indicated by the hatched area in FIG.

In the device of the first embodiment of the present invention described above, the magnetic field B is formed in the magnetic field forming portion 1g in the radial direction, and the coil 3 moves within the magnetic field B. _{Even if 1} is stroked, the distance between the magnetic field B and the coil 3 is always kept constant, so that the generated control force can be kept constant and the control force does not change depending on the stroke amount. It has the characteristic that it is excellent in property.

Further, in the first embodiment, since the inner permanent magnet 1k and the outer permanent magnet 1j are arranged in the magnetic field forming portion 1g, the magnetic field of the magnetic field forming portion 1g is strengthened, thereby increasing the control force. Is obtained.
In addition, the speed detecting coil 7c is disposed in the middle portion of the coil 3 facing the magnetic field forming unit 1g, and the speed detecting coil 7c is moved within the range of the magnetic field B of the magnetic field forming unit 1g. Even if the stroke is large, the relative speed can be detected, and the speed detection coil 7c moves in the magnetic field B having the same strength, so that a linear output characteristic proportional to the relative speed can be obtained. It has the feature that controllability can be improved.

In addition, the provision of the reinforcing permanent magnet 1f on the inner column 1a constituting the magnetic path A enhances the magnetic field of the magnetic field forming portion 1g, thereby providing a strong control force even when the stroke is increased. It has the characteristic that it can be obtained.

Further, in the middle of the magnetic field formed by the permanent magnets 1j, 1k and the reinforcing permanent magnet 1f, a reinforcing coil 1h is provided at a portion where the magnetic field is formed in the axial direction, and the respective permanent magnets 1j, 1k, 1f are provided. Is applied so that a magnetic field is generated in the same direction as the magnetic field generated by the magnetic field, the magnetic field of the magnetic field forming portion 1g becomes strong, and thus a strong control force can be obtained even when the stroke is large, and a large control force is required. When not in use, power consumption can be saved by canceling energization. Further, characterized in that when generating a damping force to the suspension unit S ₁ is intended not necessary to provide a driving current to the coil 3, it is possible to obtain controlled force without consuming power (damping force) have.

Further, since the coils 3 can be connected in parallel, a large control force can be obtained as compared with the length of the coils 3 and a high efficiency can be obtained. It has a feature that the inductance is reduced and the responsiveness is improved as compared with the case of FIG.

Next, a suspension device according to a second embodiment of the present invention shown in FIG. 8 will be described. In the description of this embodiment, the same components as those of the first embodiment are denoted by the same reference numerals, and description thereof will be omitted. Only different points will be described. Since the control relationship is the same as that of the first embodiment, the illustration is omitted.

[0044] In this embodiment, the outside of the suspension unit S _2, the free piston 5b to the sealed tank 5a
In the accumulator 5 which define between the lower fluid chamber 5c and the upper air chamber 5d provided, together with a lower fluid chamber 5c and the lower chamber E ₂ is communicated with a pipe 5e of the accumulator 5, the inner pillar 1a tip Check body 8 in place of the piston portion 1m in the first embodiment is provided in, this check body 8, allows only the flow into the lower chamber E ₂ direction from the upper chamber C ₂ through the compression side orifice 8a and the compression side check valve 8b for the extension side check valve 8d that allows only the flow from the lower chamber E ₂ to the upper chamber C ₂ direction is provided through the extension side orifice hole 8c.

[0045] Thus, in this embodiment, the vehicle body-side member 1 and the wheel-side member 2 is relatively moved when the suspension unit S ₂ is stroke, thereby, the fluid orifice 1p in the upper chamber C ₂ is in the compression stroke, the communicating and opens the compression side check valve 8b via hole 1r and the compression side orifice 8a flows out to the lower chamber E _2, the extension side check fluid in the lower chamber E ₂ is through the extension side orifice 8c in extension stroke Valve 8d
Opening the, and further flows through the communication hole 1r and orifice holes 1p in the upper chamber C ₂ side, the damping force is generated by flow of the fluid.

[0046] As described above, this suspension device to the second embodiment, and the compression side check valve 8b that allows only the flow of the lower chamber E ₂ direction from the upper chamber C ₂ through the compression side orifice hole 8a, Shin since the extension side check valve 8d to allow the lower chamber E ₂ through the side orifice hole 8c flow only into the upper chamber C ₂ direction is provided independently, the damping force in the compression phase and the extension stroke It has the feature that characteristics can be set independently.

Further, in this embodiment, by providing the accumulator 5 to the outside of the suspension unit S _2,
The suspension unit S is characterized in that a sufficient suspension stroke can be obtained without enlarging the outer shape of the suspension unit S itself.

Next, a third embodiment of the present invention will be described.

FIG. 9 is an overall view showing a suspension device according to a third embodiment of the present invention.
₃ has a vehicle body side member 20 and a wheel side member 10.

As shown in the figure, the wheel-side member 10 has an inner cylinder 10a and an outer cylinder 10 having a bottom plate 10f, an outer periphery of a central cylindrical portion 10p of the bottom plate 10f, and a lower end screwed and integrated with the outer periphery of the plate. 10b to form a double bottomed cylindrical structure having a cylindrical gap 10c between them, and a bolt member 10e for mounting to the wheel side protrudingly formed at the lower axis of the bottom plate 10f. Have been.
A substantially upper half of the outer cylinder 10b and the inner cylinder 10a is formed of a magnetic outer cylinder portion 11 and a magnetic inner cylinder portion 12 made of a ferromagnetic material, and the other portions are formed of a non-magnetic material.

On the inner peripheral surface of the magnetic outer cylinder portion 11, the upper outer permanent magnet 10j
And a lower outer permanent magnet 10k, and an upper inner permanent magnet 10m and a lower inner permanent magnet 10n are provided on the outer peripheral surface of the magnetic inner cylindrical portion 12 while maintaining a predetermined interval in the center, thereby providing an upper outer permanent magnet. An upper magnetic field forming part 10g and a lower magnetic field forming part 10h are formed between the magnet 10j and the upper inner permanent magnet 10m, and between the lower outer permanent magnet 10k and the lower inner permanent magnet 10n. I have. Further, each of the permanent magnets 10j, 10k,
Each of the permanent magnets 10j, 10k, 10m, and 10m is divided into four in the circumferential direction, and the magnetic field direction is in the radial direction with the circumferential gap 10c interposed therebetween.
A polarity direction of 10n is set. In this embodiment, the upper outer permanent magnet 10j and the upper inner permanent magnet 10m each have N poles on the inner peripheral side so that the magnetic field directions of the upper magnetic field forming unit 10g and the lower magnetic field forming unit 10h are opposite to each other. The lower outer permanent magnet 10k and the lower inner permanent magnet 10n are set so that the inner peripheral side is an S pole. That is, the upper half of the inner cylinder 10a and the outer cylinder 10b is made of a ferromagnetic material.
2, the permanent magnets 10j, 10
k, 10m, and 10n, a magnetic path A indicated by a dashed line in the figure.
Are formed in the upper and lower magnetic field forming portions 10g and 10h, the magnetic fields B ₁ and B ₁ in the radial direction and opposite to each other.
B ₂ is formed. A guide member 12 a is screwed and integrated with the upper end of the magnetic inner cylinder 12.

On the other hand, the vehicle body-side member 20 is formed in a bottomed cylindrical shape having a bottom at the upper end, and a bolt 20a for mounting to the vehicle body is erected on the upper end surface of the bottom. . The vehicle body-side member 20 is inserted into the gap 10c from the opening end, and a coil 30 is wound around the outer periphery thereof with a small gap with respect to the wheel-side member 10.

The coil 30 includes first to tenth coils 30a to 30j along the direction of relative movement of the two members 10, 20.
And each coil 30a-30j is divided into
It is wound around one bobbin 30k. The length of each of the coils 30a to 30j alone is shorter than the interval H formed between the upper outer permanent magnet 10j (upper inner permanent magnet 10m) and the lower outer permanent magnet 10k (lower inner permanent magnet 10n). Is formed. Bearings 40a, 40b, and 40c are provided between the vehicle body-side member 20 and the inner cylinder 10a and the outer cylinder 10b.

As shown in FIG. 10, the base ends of arms 80a and 80b extending in the horizontal direction are fastened to the bolt member 10e on the vehicle body side and the bolt 20a for mounting on the wheel side. the both arms 80a, is between 80b of the distal end portion each other and telescopic stroke sensor 70a is attached in response to expansion and contraction of the suspension unit S _3.

The coil 30 is connected to a control circuit 60. That is, the control circuit 60 controls each coil 30a
To 30j can be energized or short-circuited. Further, at the time of energization and short-circuit,
A variable resistor is connected to these coils 30.

[0056] Incidentally, in the case of being short-circuited coil 30, the suspension unit S ₃ is stroke,
When the coil 30 moves in a direction crossing the magnetic fields B ₁ and B ₂ of the two magnetic field forming units 10 g and 10 h, an induced current is generated in the coil 30 in proportion to the relative speed, and the induced current is consumed by the variable resistor. Then, the moving energy is reduced, that is, a damping force is obtained. On the other hand, the coil 30
Are driven, the two magnetic field forming units 10g, 10g
By energizing in a direction crossing the magnetic field B _1, B ₂ of h is performed, according to the direction the intensity of the current, the driving force is applied to the pressure direction or the driving force acting in the extension direction of the suspension unit S ₃ Or

[0057] Then, the control circuit 60, based on input from the stroke sensor 70a, the coil 30 in accordance with the stroke position of the suspension unit S ₃
An energization switching means for switching and controlling the direction of energization to a to 30j is provided. The energization switching means includes the two magnetic field forming units 1.
Since the directions of the two magnetic fields B ₁ and B ₂ at 0 g and 10 h are opposite to each other, the upper part of each of the coils 30 a to 30 j is used in order to match the acting direction of the driving force at the two magnetic field forming parts 10 g and 10 h. Magnetic field B of the magnetic field forming unit 10g
Energization of the coils 30a~30j is adapted energizing direction of the coil in a magnetic field B ₂ of the coil and the lower magnetic field forming part 10h located in _one is opposite to each other, the stroke position of the suspension unit S ₃ According to each coil 3
With switching control of the current direction of the 0a~30j is made, in which the switching control as to release the energization of the coil outside of the magnetic field B _1, B ₂ is made.

That is, each of the coils 30a to 30j is controlled within the interval H formed between the upper outer permanent magnet 10j (upper inner permanent magnet 10m) and the lower outer permanent magnet 10k (lower inner permanent magnet 10n). The energization direction is switched.

Further, the control circuit 60 in its arithmetic section, based on the input from the stroke sensor 70a,
The control is performed to keep the vehicle attitude constant, and the damping force is controlled based on input signals from the acceleration sensor 70b and the load sensor 70c.

A cylinder tube 13 is provided in the hollow portion of the inner cylinder 10a so as to define a reservoir chamber R on the outer periphery. That is, the cylinder tube 13 is provided in such a manner that upper and lower openings are fitted to a base valve 14 provided at the bottom of the inner cylinder 10a and a rod guide 15 mounted in an upper opening of the inner cylinder 10a. The cylinder tube 13 is filled with a fluid such as oil, and the reservoir chamber R is filled with a desired amount of fluid under the pressure of the sealed gas.

In the cylinder tube 13,
A piston 16 is slidably provided, and the interior thereof
And a lower chamber N. The piston 16 is fixed to a lower end of a piston rod 17 inserted from a rod insertion opening of the rod guide 15, and an upper end of the piston rod 17 penetrates a bottom of the vehicle body-side member 20, and a shaft of a bolt member 20a. It is connected and fixed to the vehicle body side member 20 by being screwed into the core. The vehicle body side member 20
A bumper bar 18 is provided on the bottom inner surface side of the.
Also, the inner cylinder 10a is provided in the upper end opening of the inner cylinder 10a.
Member 1 for sealing between the piston and the piston rod 17
9 are provided.

As shown in detail in FIG. 11, the piston 16 is provided with a pressure-side communication passage 16a and an extension-side communication passage 16b that communicate the upper chamber M and the lower chamber N. A compression damping valve 16c is provided in the upper chamber M opening of the compression communication passage 16a, and a growth damping valve 16d is provided in the lower chamber N opening of the expansion communication passage 16b.

[0063] Therefore, when the suspension unit S ₃ is stroke, when the compression stroke is passed through the compression side communication passage 16a is fluid in the lower chamber N, flows into the upper chamber M side opens the compression side damping valve 16c, these two The damping force is generated by regulating the flow of the fluid between the chambers N and M by the pressure side damping valve 16c. On the other hand, during the expansion stroke, the fluid in the upper chamber M passes through the expansion communication path 16b, opens the expansion damping valve 16d, flows into the lower chamber N, and the fluid between the two chambers M and N flows. When the flow is regulated by the extension side damping valve 16d, a damping force is generated.

That is, in the third embodiment, the electromagnetic actuator and the shock absorber are provided in series between the vehicle body and the wheels.

As described above, in the third embodiment, when performing the damping force control and the posture control, the gap 10
c, the outer magnetic tube portion 11 and the inner magnetic tube portion 1 facing each other
2 and the two opposing surfaces are separated in the direction of relative movement, and the magnetic fields B ₁ , B
_Two sets of magnets (upper outer permanent magnet 10j, lower outer permanent magnet 10k, upper inner permanent magnet 10m, lower inner permanent magnet 10n) facing each other to form two magnetic fields B ₁ and B ₂ . forming a magnetic path a, and the energizing direction for each coil 30a~30j divided into a plurality, in opposite directions in the one of the magnetic field B ₁ perpendicular to the coil and the other magnetic field B ₂ and the orthogonal coil since the stand structure and provided with a current supply switching means for switching so that, there is no need to lengthen the path a, even if increasing the stroke of the suspension unit S _3, therefore, sufficient for constant irrespective of the magnitude of the stroke It has the characteristic that control power can be obtained.

Further, in this embodiment, the upper chamber M and the lower chamber N, which increase or decrease the capacity of each other in inverse proportion by the sliding of the piston 16 accompanying the relative movement of the vehicle body-side member 20 and the wheel-side member 10, are formed. by providing, has a feature that it is possible to increase the stroke of the suspension unit S _3.

(Effects of the Invention) As described above, in the suspension device of the present invention, in addition to the electromagnetic actuator, the damping force is generated by the fluid flow generated by the relative movement between the vehicle body side member and the wheel side member. The provision of the damping means enables the damping means to obtain a damping force even when an impact exceeding the control force of the electromagnetic actuator is applied, thereby preventing the suspension unit from being damaged when a large shock is input. The effect is obtained.

[Brief description of the drawings]

FIG. 1 is an overall view showing a suspension device according to a first embodiment of the present invention.

FIG. 2 is an enlarged sectional view showing a main part of the apparatus of the first embodiment.

FIG. 3 is a sectional view taken along line RR of FIG. 1;

FIG. 4 is a circuit diagram showing a main part of a control circuit of the device of the first embodiment.

FIG. 5 is a damping force characteristic diagram of the first embodiment device.

FIG. 6 is a driving force characteristic diagram of the electromagnetic actuator of the first embodiment.

FIG. 7 is a driving force characteristic diagram of the first embodiment device.

FIG. 8 is an overall view showing a suspension device according to a second embodiment of the present invention.

FIG. 9 is an overall view showing a suspension device according to a third embodiment of the present invention.

FIG. 10 is an external view of a device according to a third embodiment.

FIG. 11 is an enlarged sectional view showing details of a piston portion in the device of the third embodiment.

[Explanation of symbols]

S ₁ Suspension unit 1 Body side member 1f Reinforcement permanent magnet (electromagnetic actuator) 1h Reinforcement coil (electromagnetic actuator) 1j Outer permanent magnet (electromagnetic actuator) 1k Inner permanent magnet (electromagnetic actuator) 1p Orifice hole (damping means) 2 Wheel Side member C ₁ Upper chamber (damping means) E ₁ Lower chamber (damping means) 3 Coil (electromagnetic actuator) S ₂ Suspension unit C ₂ Upper chamber (damping means) E ₂ Lower chamber (damping means) 5c Lower fluid chamber (damping) means) 8a pressure side orifice (damping means) 8c extension side orifice (damping means) S ₃ suspension unit 10 a wheel-side member 10j upper outer permanent magnet (electromagnetic actuator) 10k lower outer permanent magnet (electromagnetic actuator) 10 m upper inner permanent magnet (Electromagnetic actuator) 10n below Internal permanent magnet (electromagnetic actuator) 20 Body side member 16a Compression side communication path (attenuation means) 16b Extension side communication path (attenuation means) 16c Compression side attenuation valve (attenuation means) 16d Extension side attenuation valve (attenuation means) 30 Coil (electromagnetic) Actuator) R Reservoir chamber (damping means) M Upper chamber (damping means) N Lower chamber (damping means)

Claims (1)

(57) [Claims] 1. A suspension unit having a vehicle-side member and a wheel-side member formed to be relatively movable .
And one of the vehicle-side member (1) and the wheel-side member (2) is
The other part of the vehicle body-side member (1) and the wheel-side member (2) is formed in a double cylindrical structure having a gap (1c).
Material is inserted into the gap (1c) so as to be relatively displaceable in the axial direction.
Between the insertion tip and the bottom of the gap.
A liquid chamber for buffer (C1) whose volume changes based on
It is, out the fluid with the volume change of the shock absorber fluid chamber (C1)
Damping force generating means (1)
p) is provided, and magnets (1j, 1k) are provided inside and outside the gap (1c).
The member provided and inserted into the gap (1c) includes the magnet (1).
j, 1k), the coil (3) crosses the magnetic field formed by
Wound, and this coil (3) is divided into a plurality of pieces in the axial direction.
And each is connected in parallel so that the coil (3) can be energized and short-circuited.
A suspension device comprising a control circuit (6) .