JP3051502B2 - Anti-vibration device and method for controlling applied voltage of electromagnet - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an anti-vibration device which is used for an engine mount of a vehicle or an automobile and absorbs and attenuates vibration from a vibration generating portion, and a method of controlling an applied voltage of an electromagnet.

[0002]

2. Description of the Related Art Anti-vibration devices used for engine mounts, cabinet mounts, body mounts and the like for automobiles are known as:
2. Description of the Related Art There is known a vibration isolator of a liquid chamber enclosing type (Japanese Patent Laid-Open No. 60-1).
No. 13835). As shown in FIG. 9, the liquid chamber of the vibration isolator 100 is divided into a main liquid chamber 104 and a sub liquid chamber 106 by a partition wall 102, and the main liquid chamber 104 and the sub liquid chamber 106 are restricted passages 108. It is communicated with. For this reason, when the vibration is transmitted to the vibration isolator 100, the vibration is caused by the passage resistance and the liquid column resonance when the liquid filled in the main liquid chamber 104 and the sub liquid chamber 106 moves through the restriction passage. Is absorbed. Further, in the vibration isolator 100, during high-frequency vibration in which the restriction passage 108 is clogged, the movable body 112 attached to the hole 110 formed in the partition wall 102 so as to be movable within a predetermined range expands and contracts the liquid chamber. A small movement in the direction in which the pressure rises in the liquid chamber limits the pressure rise in the liquid chamber and absorbs high-frequency vibration.

However, in this vibration isolator 100, the liquid can pass not only through the restriction passage 108 but also through the gap between the movable body 112 and the hole 110. In addition, the movement of the movable body 112 causes In some cases, the amount of liquid passing through the restriction passage 108 is reduced, so that the damping effect due to the passage resistance in the restriction passage 108 cannot be sufficiently obtained.

[0004]

SUMMARY OF THE INVENTION In view of the above facts, it is an object of the present invention to provide a vibration isolator capable of reliably absorbing vibrations over a wide range of frequencies and a method for controlling an applied voltage of the electromagnet. It is.

[0005]

According to the first aspect of the present invention,
A first mounting member connected to one of the vibration generating unit or the vibration receiving unit, a second mounting member connected to the other of the vibration generating unit or the vibration receiving unit, the first mounting member and the second mounting member; An elastic body provided between the mounting member and the elastic body that is deformed when vibration occurs, a pressure-receiving liquid chamber that can expand and contract with the elastic body as a part of the partition wall, and a partition wall of the pressure-receiving liquid chamber that is formed of an elastic film. Only the diaphragm to be configured and the outer peripheral end of the diaphragm
At the center of the diaphragm so that it can be elastically deformed
A member to be attracted which is fixed and can be attracted by a magnetic force;
An electromagnet for adsorbing the member to be attracted, a sub liquid chamber separated from the pressure receiving liquid chamber, and a restriction passage communicating the pressure receiving liquid chamber with the sub liquid chamber are provided.

[0006] The method according to claim 2 is a method according to claim 1.
To control the voltage applied to the electromagnet in the vibration device
A voltage control method, wherein the time of adsorbing the adsorbing member a direct current voltage is applied to the electromagnet, the polarity predetermined small voltage applied to the electromagnet when releasing the suction of the suction member It is characterized in that the applied voltage is reduced to zero after time inversion.

[0007] The method according to claim 3 is a method according to claim 1.
To control the voltage applied to the electromagnet in the vibration device
A voltage control method, wherein the suctioned part from which suction is released
When the material is next sucked, a voltage having a polarity opposite to the polarity when the member to be sucked was previously suctioned is applied to the electromagnet.

[0008]

According to the first aspect of the present invention, for example, when the first mounting member is connected to the vibration generating section and the second mounting member is connected to the vibration receiving section, the vibration transmitted from the vibration generating section is reduced. The first mounting member, the elastic body, and the second mounting member sequentially support the vibration receiving section via the first mounting member, and the vibration is absorbed by resistance based on internal friction of the elastic body. Further, when the vibration is at a low frequency, the diaphragm of the pressure receiving liquid chamber is immovable by attracting the attracted member by the electromagnet. At this time, die
Only the outer edge of the afram is elastically deformable
The liquid passes through the restriction passage and moves between the pressure receiving liquid chamber and the sub-liquid chamber, and the liquid column resonates in the restriction passage or receives the passage resistance to effectively absorb the low frequency vibration. it can.

When the vibration becomes high in frequency, the restriction passage becomes clogged. In this case, the suction of the member to be sucked is released and the diaphragm of the pressure receiving liquid chamber is set in a free state. This ensures that the pressure change due to vibration of the receiving liquid chamber
Since the entire diaphragm vibrates and the pressure rise in the pressure receiving liquid chamber is suppressed, a low dynamic spring constant of the vibration isolator can be obtained. Therefore, high frequency vibrations can be effectively absorbed.

[0010] According to the method of claim 2, wherein, when the adsorption of the adsorbed member <br/> applies a DC voltage to the electromagnet, the suction unit
When releasing the adsorption of the material , the polarity of the voltage applied to the electromagnet is reversed for a predetermined minute time, and then the applied voltage is set to zero. That is, when the attracted member is released from the attraction, the magnetic force of the electromagnet becomes zero after the polarity is reversed for a predetermined minute time. Therefore, since the magnetic force of the electromagnet is made zero after being made the same polarity as the residual magnetism of the attracted member magnetized at the time of adsorption for a short time, the attracted member can be instantly separated by being repelled by the electromagnet.

According to the third aspect of the present invention, when the suctioned member whose suction has been released is next sucked, the previous suctioned portion is removed.
A voltage having a polarity opposite to the polarity when the material is attracted is applied to the electromagnet. For this reason, the next time the attracted member that has been released is attracted, the electromagnet has a polarity opposite to the polarity when the attracted member was previously attracted. That is, since the electromagnet and the attracted member is alternately magnetized poles in each adsorption hardly the magnetized electromagnet and the attracted member as compared with a method of adsorption with specific polarity. Further, there is little possibility that a member such as iron disposed around the electromagnet is magnetized.

[0012]

【Example】

[First Embodiment] A vibration isolator 10 according to a first embodiment of the present invention.
Will be described with reference to FIGS.

As shown in FIGS. 1 and 2, the vibration damping device 10 is provided with a mounting frame 12 for mounting to a vehicle body (not shown). 16 has been inserted. A thin rubber layer 18 is vulcanized and bonded inside the outer cylinder 16. The thin rubber layer 18 is separated from the outer cylinder 16 by a circular hole 22 formed in the upper part of the outer cylinder 16 to form a small diaphragm 26, and is formed by a rectangular hole 24 formed in a lower part of the outer cylinder 16. To form a large diaphragm 28 apart from the outer cylinder 16.

An intermediate block 25 formed in a substantially cylindrical shape is inserted into the outer cylinder 16, and the outer peripheral surface in the radial direction is closely attached to the inner peripheral surface of the thin rubber layer 18. The intermediate block 25 includes an intermediate cylinder 32, an inner cylinder 34, and the elastic body 3.
6 are integrally formed, the intermediate cylinder 32 and the inner cylinder 3
4 is arranged coaxially with the outer cylinder 16.

The elastic body 36 of the intermediate block 25 is formed with a cutout 23 at an upper middle portion in the axial direction and a cutout 27 at a lower middle portion in the axial direction. A cavity 70 is formed below the inner cylinder 34 between the intermediate cylinder 32 and the elastic body 36, and the cavity 70 passes through the intermediate block 25 in the axial direction.

The notch 23 is surrounded by the thin rubber layer 18 and the small diaphragm 26 to form a pressure receiving liquid chamber 38, and the notch 27 is formed by the thin rubber layer 18 and the large diaphragm 28.
The sub liquid chamber 40 is surrounded by the sub liquid chamber 40.

On the other hand, a groove 42 is formed on the outer peripheral surface of the intermediate block 25 along the outer peripheral direction. One of the grooves 42 is connected to the notch 27 and the other is connected to the notch 23.
Is composed.

The pressure receiving liquid chamber 38, the auxiliary liquid chamber 40, and the restriction passage 44 are filled with a liquid such as water or oil. An air chamber 46 is provided on the side of the large diaphragm 28 opposite to the side of the sub-liquid chamber 40, and communicates with the outside as needed.

As shown in FIG. 2, this small diaphragm 2
6 is the center of the outer surface in the radial direction excluding the outer edge
The steel plate 30 is fixed to the portion . The steel plate 30 is formed in a disk shape, and further curved in an arc shape along the inner peripheral shape of the annular portion 14. In the small diaphragm 26, in a free state, the steel plate 30 is separated from the inner peripheral surface of the annular portion 14 by a predetermined dimension (see FIG. 2). In addition,
A space formed between the annular portion 14 and the small diaphragm 26 is an air chamber 45.

On the other hand, a hole 48 is formed in the annular portion 14 of the mounting frame 12 coaxially with the circular hole 22 of the outer cylinder 16. Is arranged. The electromagnet 50 includes a case 51, a magnetic core 52, and a coil 54 wound around the magnetic core 52, and the case 51 is fixed to the annular portion 14. The magnetic core 52 is located at a position where the tip surface 52A on the hole 48 side is in contact with a tangent line on the inner periphery of the annular portion 14. The coil 54 of the electromagnet 50 is connected to a DC power supply 56 such as a battery and a control means 58. When one of the wires 54A drawn from the coil 54 is made positive and the other 54B of the wire is made negative, The tip surface 52A side of the magnetic core 52 becomes the N pole. When one of the wires 54A drawn out of the coil 54 is made negative and the other 54B of the wire is made positive, the tip surface 52A side of the magnetic core 52 becomes an S pole.
The control means 58 is connected to at least a vehicle speed sensor 60 and an engine speed sensor 62, and switches ON / OFF and polarity of the voltage applied to the coil 54 based on the vehicle speed and the engine speed.

Next, the operation of the present embodiment will be described. When the mounting frame 12 is connected to an engine (not shown) that is a vibration source and the inner cylinder 34 is fixed to a vehicle body such as an automobile (not shown), the vibration generated in the engine is reduced by the elastic body 36 through the mounting frame 12. The vibration can be absorbed by the vibration damping function based on the internal friction of the elastic body 36.

At this time, the control means 58 controls the vehicle speed sensor 60
When the control means 58 determines that the vibration is low-frequency vibration based on the detection signal from the engine speed sensor 62, the control means 58 energizes the coil 54 of the electromagnet 50. At this time, one of the conductors 54A is made positive, the other 54B of the conductor is made negative, and the tip surface 52A side of the magnetic core 52 becomes the N pole. As a result, the steel plate 30 is turned to the S pole on the magnetic core 52 side, the steel plate 30 is attracted to the magnetic core 52, and the steel plate 30 and the small diaphragm 26 adhere to the inner peripheral surface of the annular portion 14, and the pressure receiving liquid chamber 38
Movement due to pressure changes in the interior is prevented. For this reason, the liquid moves between the pressure receiving liquid chamber 38 and the auxiliary liquid chamber 40 via the restriction passage 44 to vibrate the large diaphragm 28, and the liquid column resonates in the restriction passage 44 and receives the passage resistance and receives the low frequency. Absorb vibration.

On the other hand, when the frequency of the vibration input to the vibration isolator 10 increases, the restriction passage 44 becomes clogged. When the control means 58 determines that the vibration is high-frequency vibration based on detection signals from the vehicle speed sensor 60 and the engine speed sensor 62, as shown in FIG. 4, the applied voltage is turned off after reversing the polarity of the applied voltage for a predetermined time. I do. Steel plate 30
Since the magnetic core 52 side has the opposite polarity to the magnetic core 52 due to residual magnetism not only while the current flowing through the coil 54 but also after the current flowing through the coil 54 is turned off, Turns off after inverting the polarity of the applied voltage for a predetermined time,
That is, by turning off the applied voltage after the tip surface 52A side of the magnetic core 52 is set to the S pole, the steel sheet 30 rebounds and can be instantaneously separated from the magnetic core 52. The time during which the polarity of the applied voltage is reversed is set to a time during which the repelled steel plate 30 is not attracted to the magnetic core 52 again. Thereby, as shown in FIG. 3, the small diaphragm 26 is separated from the inner peripheral surface of the annular portion 14 and becomes free. The small diaphragm 26 vibrates due to a pressure change due to the vibration in the pressure receiving liquid chamber 38, and the pressure rise in the pressure receiving liquid chamber 38 is suppressed, so that a low dynamic spring constant of the vibration isolator 10 is obtained.

[Second Embodiment] FIG. 5 shows a second embodiment of the present invention.
It is explained according to. The same components as those of the first embodiment are denoted by the same reference numerals, and description thereof will be omitted.

In this embodiment, an air hole 64 communicating with the atmosphere is formed in the annular portion 14 corresponding to the air chamber 45.
The air in the air chamber 45 can freely move to and from the atmosphere side. For this reason, the movement of the small diaphragm 26 due to the pressure change of the liquid in the pressure receiving liquid chamber 38 is improved, and the small diaphragm 26 can vibrate to a higher frequency range,
Vibration in a wider frequency range can be absorbed as compared with the case where the air chamber 45 is sealed.

[Third Embodiment] FIG. 6 shows a third embodiment of the present invention.
It is explained according to. The same components as those of the first embodiment are denoted by the same reference numerals, and description thereof will be omitted.

As shown in FIG. 6, in the present embodiment, the steel plate 30
Is provided with a small protrusion 66 formed of an elastic body. For this reason, the contact noise when the steel plate 30 is attracted to the magnetic core 52 of the electromagnet 50 and contacts the inner peripheral surface of the annular portion 14 and the magnetic core 52 is reduced.

[Fourth Embodiment] FIG. 7 shows a fourth embodiment of the present invention.
It is explained according to. The same components as those of the first embodiment are denoted by the same reference numerals, and description thereof will be omitted.

In this embodiment, a gap (dimension t in FIG. 7) is provided between the distal end surface 52A of the magnetic core 52 of the electromagnet 50 and the inner peripheral surface of the annular portion 14, and the distal end surface 52A of the magnetic core 52 is Is fixed to an annular elastic body 68, and the elastic body protrudes from the tip end face 52 </ b> A of the magnetic core 52 toward the steel plate 30 by a predetermined dimension. Therefore, also in this case, as in the second embodiment, the contact sound when the steel plate 30 is attracted to the magnetic core 52 of the electromagnet 50 and contacts the inner peripheral surface of the shape portion 14 and the magnetic core 52 is prevented. .

[Fifth Embodiment] FIG. 8 shows a fifth embodiment of the present invention.
It is explained according to. The configuration of the present embodiment is the same as that of the first embodiment, so that the illustration is omitted.

In this embodiment, as shown in FIG. 8, when the steel sheet 30 is attracted again after the applied voltage is turned off, the tip surface 52A of the magnetic core 52 is set to the opposite pole to the previous one. Thus, the control means 58 applies a voltage to the coil 54. As described above, since the magnetic core 52 and the steel plate 30 are magnetized to alternate poles each time the magnetic core 52 and the steel plate 30 are magnetized, the magnetic core 52 and the steel plate 30 are hardly magnetized. Further, the possibility that the iron members disposed around the magnetic core 52 and the steel plate 30 are magnetized is reduced.

In this embodiment, the electromagnet 50 is driven by a direct current. However, the present invention is not limited to this. The electromagnet 50 only needs to be able to adsorb the steel plate 30, and the electromagnet 50 is driven by an alternating current. It may be configured.

In the present embodiment, the steel plate 30 is used as the means to be adsorbed. However, the present invention is not limited to this, and the means to be adsorbed may be other materials such as stainless steel, iron alloy, and resin. Any material can be used as long as it is attracted by magnetic force.

In this embodiment, the small diaphragm 26
Although the present invention is not limited to this configuration, the present invention is not limited to this, and a configuration in which an adsorption target such as a steel plate is buried in the small diaphragm 26 may be adopted, or a configuration in which metal powder such as iron is buried in the small diaphragm 26. It may be. Further, the small diaphragm 26 may be formed of an elastic body mixed with metal powder such as iron.

In order to reduce the contact noise between the steel plate 30 and the magnetic core 52 of the electromagnet 50, the steel plate 30 or the magnetic core
A thin cushioning material such as a resin may be attached to the abutting portion.

In each of the embodiments, the configuration in which the present invention is applied to the bush type vibration isolator is shown. However, the present invention may be applied to a vibration isolator having a structure other than the bush type. is there.

[0037]

As described above, the anti-vibration device of the present invention has the above-described configuration, and therefore has an excellent effect of reliably absorbing vibration over a wide frequency range.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view showing a vibration isolator according to a first embodiment of the present invention.

FIG. 2 is a sectional view showing a vibration isolator according to the first embodiment of the present invention.

FIG. 3 is a cross-sectional view showing the vibration isolator according to the first embodiment of the present invention, showing a state where a small diaphragm is in close contact with the inner periphery of an annular portion.

FIG. 4 is a graph showing a waveform of a voltage applied to a coil.

FIG. 5 is a sectional view showing a vibration isolator according to a second embodiment of the present invention and showing an annular portion.

FIG. 6 is a sectional view showing a vibration isolator according to a third embodiment of the present invention and showing a small diaphragm.

FIG. 7 is a sectional view showing a vibration isolator according to a fourth embodiment of the present invention and showing a small diaphragm.

FIG. 8 is a graph showing a waveform of a voltage applied to a coil according to a fifth embodiment of the present invention.

FIG. 9 is a cross-sectional view illustrating a conventional vibration damping device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Vibration isolator 16 Outer cylinder (first attachment member) 26 Small diaphragm (elastic film) 30 Steel plate (means to be adsorbed) 34 Inner cylinder (second attachment member) 36 Elastic body 38 Pressure receiving liquid chamber 40 Secondary liquid chamber 44 Restricted passage 50 electromagnet

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) F16F 13/26 F16F 13/10 B60K 5/12 H01F 7/18

Claims (3)

(57) [Claims] A first mounting member connected to one of the vibration generating section and the vibration receiving section; a second mounting member connected to the other of the vibration generating section and the vibration receiving section; and the first mounting section An elastic body that is provided between the member and the second mounting member and that is deformed when vibration occurs, a pressure-receiving liquid chamber that can expand and contract the elastic body as a part of a partition, and an elastic film that is formed of an elastic film . a diaphragm constituting a part of the partition wall, outside the diaphragm
The diaphragm is deformed so that only the peripheral end can be elastically deformed.
Is fixed to the center of the drum and can be attracted by magnetic force
A member to be attracted, an electromagnet for attracting the member to be attracted, a sub-liquid chamber separated from the pressure-receiving liquid chamber, and a restriction passage communicating the pressure-receiving liquid chamber with the sub-liquid chamber. Anti-vibration device. 2. An electromagnet in the vibration isolator according to claim 1.
Voltage control method for controlling the voltage applied to the
Then , a DC voltage is applied to the electromagnet when the member to be attracted is attracted, and the polarity of the voltage applied to the electromagnet is reversed for a predetermined minute time when the attraction of the member to be attracted is released. An applied voltage control method for an electromagnet, wherein the applied voltage is set to zero. 3. An electromagnet in the vibration isolator according to claim 1.
Voltage control method for controlling the voltage applied to the
Te, when then adsorbing the object to be attracted member is released adsorption, the polarity at the time of adsorbing the last said the attracted member and applying an opposite polarity voltage to said electromagnet electromagnet Applied voltage control method.