JP2584670Y2 - Active mount - 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 for supporting and supporting a vibrating body such as an engine of an automobile, and more particularly to an active mount effective for attenuating vibrations (idle vibrations, etc.) in a medium / high frequency range. Things.

[0002]

2. Description of the Related Art Generally, an automobile engine has a large amplitude (± 0.25 m) when idling.
m) Since vibrations of small amplitude (± 0.05 mm) are generated during traveling, a vibration isolator capable of effectively attenuating these vibrations is strongly demanded. In particular, in view of the traffic situation in Japan where traffic congestion frequently occurs, it is an important task to completely eliminate idle oscillation having a large amplitude.

As an anti-vibration device capable of attenuating such vibrations, for example, an anti-vibration device disclosed in Japanese Patent Application Laid-Open No. HEI 3-24338 is already known. This anti-vibration device is a so-called active mount. The liquid column resonance when the liquid moves between the working chamber and the pressure regulating chamber via the buffer hole attenuates low-frequency vibrations (shock vibrations and the like), thereby reducing the vibration of the actuator diaphragm. By generating a pulsation of the opposite phase to the vibration input to the liquid in the working chamber by driving,
Vibration in a high frequency range (such as idle vibration) is attenuated.

However, since the amount of energy generated by the electric system is small in the idling rotation range, the energy consumption as a whole must be reduced, and the energy consumption of the actuator must also be suppressed. Therefore, even in the active mount described above, it is necessary to reduce the size of the diaphragm of the actuator and reduce the capacity of the magnet system for driving the diaphragm, and the driving range of the diaphragm is limited to a small extent. However, sufficient pulsation to attenuate the input vibration cannot be given to the liquid in the working chamber.

The present invention solves the above-mentioned problems of the prior art. By combining the change in hydraulic pressure by the actuator with the resonance of the orifice, it is possible to reduce the size and capacity of the actuator. It is another object of the present invention to provide an active mount capable of sufficiently attenuating vibrations (idle vibrations and the like) in a medium / high frequency range.

[0006]

In order to solve the above-mentioned problems, the present invention relates to a case in which a case is connected to a top surface of a partition via a supporting spring, and a driving member and a driving member are provided in the case. Providing a driven member that can be driven,
A main liquid chamber is formed in a portion surrounded by the driven member, the support spring, and the partition, and further, a sub liquid chamber surrounded by a diaphragm is formed on the lower surface side of the partition, and the main liquid chamber and the sub liquid chamber are formed in the partition. A first orifice that communicates with the auxiliary liquid chamber that is partitioned from the main liquid chamber via a first displacement member, and is partitioned from a sub liquid chamber via a second displacement member;
A means provided with a second orifice communicating between the auxiliary liquid chamber and the sub liquid chamber is employed.

[0007]

According to the present invention, the liquid is moved between the main liquid chamber and the sub liquid chamber through the first orifice up to the resonance frequency range of the first orifice by employing the above-mentioned means. The input vibration is attenuated by the liquid column resonance at the time of fitting.
When the resonance frequency of the first orifice is exceeded, the inertia of the liquid column increases, so that the liquid does not move between the main and sub liquid chambers through the first orifice. Here, when the driven member is driven by the driving member, pulsation having a phase opposite to that of the vibration input to the liquid in the main liquid chamber can be given. However, this alone can completely attenuate the vibration in this frequency range. Can not. Then, the liquid pressure in the main liquid chamber gradually increases due to the input vibration, and the first displacement member of the partition wall is displaced in accordance with the change in the liquid pressure in the main liquid chamber, and the auxiliary liquid chamber changes in volume. The liquid in the auxiliary liquid chamber moves toward the sub liquid chamber via the second orifice due to the change in volume of the auxiliary liquid chamber. Due to the liquid column resonance when the liquid moves between the auxiliary liquid chamber and the sub liquid chamber via the second orifice, the load left by the driven member can be absorbed.
When the resonance frequency of the second orifice is exceeded, the inertia of the liquid column increases, so that the liquid does not move between the auxiliary liquid chamber and the auxiliary liquid chamber via the second orifice. When the driven member is driven by the driving member, pulsation sufficient to attenuate the vibration input to the liquid in the main liquid chamber can be given, and the dynamic spring is set to a value close to zero. can do.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention shown in the drawings will be described below. 1 and 2 show one embodiment of the active mount according to the present invention. FIG. 1 is a schematic sectional view showing the whole, and FIG. 2 shows the relationship between the dynamic spring and the frequency of the one shown in FIG. FIG.

More specifically, the active mount has a case 1 having a cylindrical shape with an upper end closed and a screw portion 1a provided at the center of the upper surface, and a substantially cylindrical shape having one end connected to the lower end opening of the case 1. A support spring 2 made of a rubber-like elastic material, a partition 3 connected to the other end of the support spring 2, and a diaphragm 4 provided on the lower surface side of the partition 3
And a main liquid chamber 12 in a portion surrounded by the actuator 5, the support spring 2 and the partition 3, and a sub-liquid chamber 13 in a portion surrounded by the partition 3 and the diaphragm 4. However, auxiliary liquid chambers 14 are respectively formed in the partition walls 3, and the respective liquid chambers 12, 13, 1
4 is filled with an incompressible liquid such as water or oil.

The actuator 5 is connected to the inner surface of the case 1 via a spring member 15 made of a rubber-like elastic material or the like, and is driven by a magnetizable material whose lower surface faces the main liquid chamber 12. A diaphragm 11 which is a member;
And a driving member 6 for driving the vibration plate 11.

The drive member 6 has an outer peripheral side fitted to the inner surface of the case 1 above the diaphragm 11 and
And a disk-shaped yoke 8 facing with a predetermined gap therebetween
A substantially disk-shaped permanent magnet 10 mounted at the center of the surface of the yoke 8 facing the diaphragm 11;
And a coil 9 mounted in the groove 8a of the yoke 8 at the peripheral edge of the electromagnet 7. The coil 9 and the yoke 8 constitute an electromagnet 7, and the vibration of the The plate 11 is driven against the spring force of the spring member 15.

The diaphragm 4 is formed in a thin bowl shape made of a rubber-like elastic material, and its peripheral portion is caulked to the lower surface side of the partition wall 3 by the peripheral portion of a bowl-shaped lid member 16. At the center of the lid member 16 is provided a screw portion 16a for connecting to the body side.

The partition 3 has a substantially disk shape.
A through-hole 3a penetrating from the upper surface side to the lower surface side is formed in the center, and the upper surface side opening (the main liquid chamber 12 side) has a first spring constant made of a rubber-like elastic material. Closed by the displacement member 17, the lower opening (the side of the auxiliary liquid chamber 13)
Is a second material having an appropriate spring constant made of a rubber-like elastic material.
Are closed by the displacing members 18, and these displacing members 17, 18
The auxiliary liquid chamber 14 is formed between them.

The main liquid chamber 12 and the sub liquid chamber 13 communicate with each other through a thin and long first orifice 19 formed in the partition wall 3. The auxiliary liquid chamber 14 and the sub liquid chamber 13 communicate with each other via a second orifice 20 which is thicker and shorter than the first orifice 19 formed in the partition wall 3. I have.

Next, FIG.
This will be described with reference to FIG. First, the case 1 of the active mount configured as described above is connected to an engine side (not shown) via a screw portion 1a at the center on the upper surface side, and the cover member 16 is shown via a screw portion 16a at the center. Not connected to the body side and operating the engine,
Various vibrations are input to the case 1 from the engine.

[0016] Here, in advance, a desired frequency within 5～10H _Z resonance frequency of the first orifice 19 (during running) (e.g. 7H _Z), the resonance frequency of the second orifice 20 20~30H _Z ( If you set the desired frequency of idling) in (e.g., 23H _Z), in the frequency range of 0~7H _Z, the main liquid chamber via the first orifice 19 12
The liquid freely moves between the main liquid chamber 13 and the auxiliary liquid chamber 13, there is no increase in the liquid pressure in the main liquid chamber 12, and the dynamic spring is equal to the supporting spring 2.

When the resonance frequency of the first orifice 19 becomes near, the inertia of the liquid passing through the first orifice 19 causes a shift in the phase of the movement of the liquid with respect to the input vibration. Fluid pressure pulsates. The pulsating increases gradually with increasing frequency, acting on the hydraulic rise opposite by vibration near resonance of 7H _Z, the effect of the movement and the phase of the liquid reaches a peak becomes maximum. Therefore, by setting the resonance frequency of the first orifice 19 to a desired value, it is possible to effectively attenuate shock vibration and the like during traveling.

[0018] In addition, in the frequency range of 7H _Z ~23H _Z is,
Since the liquid column inertia of the first orifice 19 is increased, the liquid does not move between the main and sub liquid chambers 12 and 13 via the first orifice 19.

Here, the driven member 11 is driven by the driving member 6 of the actuator 5, that is, the diaphragm 11 is vibrated by the cooperation of the electromagnet 7 and the permanent magnet 10, and the vibration is input to the liquid in the main liquid chamber 12. When a pulsation having a phase opposite to that of the generated vibration is generated, the load to be transmitted to the partition 3 side is absorbed by the change in the hydraulic pressure. It cannot be completely absorbed.

As a result, the hydraulic pressure in the main liquid chamber 12 gradually increases due to the vibration input from the engine, and accordingly, the first displacement member 17 of the partition wall 3 bends. The volume of the auxiliary liquid chamber 14 changes according to the amount of bending, and the liquid in the auxiliary liquid chamber 14
And moves to the sub-liquid chamber 13 side, and the remaining load is absorbed. The dynamic spring in this frequency range is obtained by adding the load generated by the displacement of the support spring 2 to the load generated by the increase in the hydraulic pressure of the main liquid chamber 12.

When the resonance frequency of the second orifice 20 becomes near, the inertia of the liquid passing through the second orifice 20 causes a shift in the phase of the movement of the liquid with respect to the input vibration. Fluid pressure pulsates. The pulsating increases gradually with increasing frequency, acting on the hydraulic rise opposite by vibration in the vicinity of the resonance of 23H _Z, the effect of the movement and the phase of the liquid reaches a peak becomes maximum. Therefore, by setting the resonance frequency of the second orifice 20 to a desired value, idle vibration and the like can be effectively attenuated.

Further, at a frequency range in excess of 23H _Z, since the liquid column inertia of the second orifice 20 is increased, the liquid between the first orifice 19 auxiliary liquid chamber 14, the secondary liquid chamber 13 each other through a However, since the amplitude of the vibration input from the engine gradually decreases in this frequency range, it is possible to sufficiently cope with the change in the hydraulic pressure by the actuator 5 alone. Therefore, the diaphragm 11 which is a driven member is kept in a driving state by the cooperation of the electromagnet 7 and the permanent magnet 10 constituting the driving member 6, and the pulsation having the opposite phase to the input vibration is generated in the liquid in the main liquid chamber 12. In this case, the value of the dynamic spring can be set to a value close to 0, thereby making it possible to prevent the occurrence of muffled noise and the like in this frequency range.

As described above, in the active mount according to this embodiment, the vibration in the low frequency range can be attenuated by utilizing the liquid column resonance action of the first orifice 19 of the partition wall 3, and furthermore, By utilizing the liquid column resonance action of the second orifice 20 of the partition wall 3 and the change of the hydraulic pressure by the actuator 5, it is possible to attenuate the vibration in the middle / high frequency range and to reduce the resonance frequency of the second orifice 20. By using the actuator 5 in the frequency range exceeding, a low dynamic spring close to zero can be obtained.

Therefore, the size of the diaphragm 11 as a driven member of the actuator 5 is increased, and the size of the electromagnet 7 and the permanent magnet 10 as the driving members for driving the diaphragm 11 is not increased, so that the actuator is small and small in capacity. 5 can sufficiently attenuate vibrations in the middle and high frequency regions (idle vibrations and the like), and can be effectively used in places where energy saving is required, such as automobile engines.

[0025]

According to the present invention, as described above, in the low frequency range, a liquid column resonance effect when liquid moves between the main and sub liquid chambers of the first orifice is used. As a result, high damping can be obtained, and shock vibration and the like during running can be effectively damped. In the middle and high frequency regions, the liquid column when the liquid moves between the auxiliary liquid chamber and the sub liquid chamber via the second orifice in response to the change in the liquid pressure of the main liquid chamber due to the driven member. By combining the resonance action, idle vibration and the like during idle rotation can be effectively attenuated. Further, in the frequency range exceeding the resonance frequency of the second orifice, the liquid column inertia increases, so that the liquid does not move between the auxiliary liquid chamber and the sub liquid chamber via the second orifice. Since the amplitude of the incoming vibration also gradually decreases, by maintaining the driven member in the driven state, it is possible to give sufficient pulsation to attenuate the vibration input to the liquid in the main liquid chamber. Therefore, the dynamic spring in this frequency range can be set to a value close to 0, and the generation of muffled sound and the like can be completely prevented. As described above, by selectively using the first orifice, the second orifice, the driven member and the driving member according to the frequency, the driven member can be reduced in size without increasing the size of the driven member and increasing the capacity of the driving member. It is possible to sufficiently attenuate vibrations in the middle and high frequency ranges even with a driven member having a small capacity and a driving member having a small capacity, so that it can be effectively used even in an automobile engine or the like that requires energy saving. It has excellent effects such as becoming.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing an entire embodiment of an active mount according to the present invention.

FIG. 2 is an explanatory diagram showing a relationship between a dynamic spring and a frequency of the one shown in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Case 1a ... Thread part 2 ... Support spring 3 ... Partition wall 3a ... Through-hole 4 ... Diaphragm 5 ... Actuator 6 ... Drive member 7 ... Electromagnet 8 ... Yoke 8a ... Groove 9 ... … Coil 10… Permanent magnet 11… Driven member (diaphragm) 12… Main liquid chamber 13… Sub liquid chamber 14… Auxiliary liquid chamber 15… Spring member 16… Lid member 16a… Screw 17 first displacement member 18 second displacement member 19 first orifice 20 second orifice

Claims (1)

(57) [Scope of request for utility model registration] 1. A case (1) is connected to an upper surface of a partition (3) via a support spring (2).
A driving member (6) and a driven member (11) that can be driven by the driving member (6) are provided therein, and a portion surrounded by the driven member (11), the support spring (2), and the partition (3). A main liquid chamber (12), and further a partition (3)
A sub liquid chamber (13) surrounded by a diaphragm (4) is formed on the lower surface side of the first liquid chamber, and a first liquid chamber (13) communicating with the main liquid chamber (12) and the sub liquid chamber (13) is formed in the partition wall (3). The orifice (19) is partitioned from the main liquid chamber (12) via the first displacement member (17), and is partitioned from the sub-liquid chamber (13) via the second displacement member (18). An active mount, comprising: an auxiliary liquid chamber (14); and a second orifice (20) communicating between the auxiliary liquid chamber (14) and the auxiliary liquid chamber (13).