JPS6322353Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a vibration isolating rubber device, and particularly to a vibration isolating rubber device for engine mounting used to mount an engine to a vehicle body of a vehicle such as an automobile.

Engines in vehicles such as automobiles are generally
It is elastically supported from the vehicle body by a vibration isolating rubber device to prevent engine vibrations from being transmitted to the vehicle body.

In order to effectively damp engine vibrations, the anti-vibration rubber device must be configured to exhibit high damping performance against low-frequency vibrations and a small dynamic spring constant against high-frequency vibrations. Preferably, in view of this, two frames, and a rubber-like elastic body extending between the two frames to connect them and working together with the two frames to define a room space. Anti-vibration rubber devices have already been proposed which have an annular wall element and a restricting passage through which fluid enters and exits the chamber space. This anti-vibration rubber device mainly absorbs high-frequency vibrations by the vibration damping effect caused by the internal friction of the rubber-like elastic body that constitutes the annular wall element, and by absorbing high-frequency vibrations by the movement of fluid in and out of the room space through the constriction passage. Mainly absorbs low frequency vibrations through viscous damping. The viscous damping effect becomes more pronounced as the degree of restriction applied to the fluid flow in and out of the chamber space through the restriction passage becomes larger, that is, as the effective passage cross-sectional area of the restriction passage becomes smaller. The internal pressure of the space increases, the effective spring constant of the vibration-isolating rubber device increases, and the damping effect of high-frequency vibrations decreases.

Therefore, although the vibration isolating rubber device as described above has the effect of damping both high-frequency vibrations and low-frequency vibrations, it is unable to attenuate either of them at a high damping rate. Particularly in the case of vibration isolating rubber devices for engine mounting, if the specifications of the vibration isolating rubber device are determined so as to obtain a good vibration isolating effect during steady operation, the engine torque will be reduced during acceleration. When the engine vibrates significantly due to fluctuations in the engine speed, low-frequency vibrations are not sufficiently damped, and the engine vibrations are transmitted to the vehicle body. On the other hand, if the specifications of the vibration isolating rubber device are determined so that a good vibration damping effect can be obtained during acceleration, high frequency vibrations will not be sufficiently damped during steady operation.

An object of the present invention is to provide an improved vibration isolating rubber device as described above, which can selectively attenuate high frequency vibrations and low frequency vibrations at a high damping rate.

This purpose, according to the present invention, includes two frames and a rubber-like elastic body extending between the two frames, connecting them, and working together with the frames to define a room space. It has an annular wall element, a throttle passage that allows fluid to enter and exit the chamber space, an elastic thin film to which the pressure of the chamber space is applied to one surface through the communication passage, and a valve that opens and closes the communication passage. This is achieved by using a vibration isolating rubber device such as the one shown below.

According to this configuration, when the communication path is open, the pressure of the chamber space is applied to the elastic thin film, and the elastic thin film is elastically deformed due to a change in this pressure, thereby suppressing a rise in the pressure, and reducing the pressure in the chamber space. This prevents the spring constant of the vibration-isolating rubber device from increasing due to an increase in internal pressure, and effectively damps high-frequency vibrations. On the other hand, when the communication passage is closed by a valve, the internal pressure of the chamber space is no longer applied to the elastic thin film, and at this time, fluid in the chamber space enters and exits through the throttle passage in response to pressure fluctuations in the chamber space. The viscous damping effect of the fluid flow effectively damps low frequency vibrations.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to the accompanying drawings.

FIGS. 1 and 2 show one embodiment of a vibration isolating rubber device according to the present invention. In the figure, 1 and 2 each indicate a frame. The frame 1 is composed of one flat plate member, and the frame 2 is composed of one flat plate member 2b.
and a bowl-shaped member 2a having a hole 2c in the center. The frame body 1 and the bowl-shaped member 2a are opposed to each other, and they are connected to each other by an annular wall element 3 made of a rubber-like elastic material such as rubber or rubber-like material provided between them. has been done.

A rod member 4 is provided inside the annular wall element 3. The rod member 4 is fixed to the frame 1 near one end, and the other end of the rod member 4 is fixed to the frame 1 through the hole 2c.
It is located inside the bowl-shaped member 2a via the flange member 5, and a flange member 5 is fixed to this end. An annular rubber-like elastic member 6 made of rubber or rubber-like material is provided between the outer peripheral edge of the flange member 5 and the inner peripheral part of the bowl-shaped member 2a. 3, the bowl-shaped member 2a, and the flat plate member 2b, the sealed space is divided into two chamber spaces 7 and 8 by the flange member 5 and the rubber-like elastic material 6.

An elastic thin film chamber member 9 is fixed to the flange member 5. An elastic thin film 10 made of rubber or rubber-like material is attached to the elastic thin film chamber member 9, and the elastic thin film has a first elastic thin film chamber 11 on one side and a second elastic thin film chamber 11 on the other side. Each of the elastic thin film chambers 12 is defined as follows. First elastic thin film chamber 1
1 communicates with the chamber space 7 through a plurality of communication holes 13 provided in the flange member 5, and the second elastic thin film chamber 12 communicates with the chamber space 7 through a plurality of communication holes 14 provided in the elastic thin film chamber member 9. They each communicate with the room space 8 through the passageway. A throttle hole 15 is provided in the flange member 5 and the elastic thin film chamber member 9, and the chamber spaces 7 and 8 communicate with each other through this throttle hole.

A valve element 16 is mounted on the rod member 4 and is rotatable about the axis of the rod member. Valve member 1
6 is in slidable contact with one surface of the flange member 5, and a valve hole 17 selectively aligns with the communication hole 13 and a valve hole 18 selectively aligns with the throttle hole 15 depending on the rotational position. It has The communication hole 13 and the valve hole 17 are both circular holes, and as the valve element 16 rotates, the valve hole 17 is biased to one side from the communication hole 13 and separated from it, so that the communication hole 13 becomes the valve element 1.
6, and communication between the first elastic thin film chamber 11 and the chamber space 7 is cut off. Orifice hole 15
is a round hole, whereas the valve hole 18 extends along an arc centered on the rotation center of the valve element 17, and its radial opening width gradually decreases from one end toward the other end. The hole is a long hole, and as the alignment between the orifice hole 15 and the valve hole 18 changes as the valve element 17 rotates, the effective passage cross-sectional area of the orifice hole 15 is proportional to the amount of rotation of the valve element 17. Changes to

The valve element 17 is provided with an arc-shaped elongated hole 19 centered on the center of rotation of the valve element, and one end surface of the elongated hole 19 is provided with a series of lock teeth 20. A servo motor 22 is attached to the rod 4 by a mounting member 21, and a pinion 24 is attached to a rotating shaft 23 of the servo motor, and the pinion 24 meshes with the rack teeth 20. The servo motor 22 rotates the valve element 16 through a pinion 24 and rack teeth 20 by rotation of a rotating shaft 23. The opening/closing of the communication hole 13 by the valve element 16 and the increase/decrease control of the effective opening area of the orifice hole 15 are controlled by the servo motor 2.
2 is controlled, and when the rotation shaft 23 of the servo motor 22 is at the initial rotation angle position, the valve hole 17 is aligned with the communication hole 13, and the first elastic thin film chamber 11 and the chamber space 7 are are in communication with each other, and the orifice hole 15 is aligned with the widest part of the valve hole 18, so that its effective opening area is maximized,
When the rotation shaft 23 of the servo motor 22 is at the first rotation angle position displaced by a predetermined rotation angle from the initial rotation angle position, the return hole 17 is separated from the communication hole 13 and is connected to the first elastic thin film chamber 11. Communication with the chamber space 7 is cut off, and the orifice hole 15 is moved away from alignment with the widest portion of the valve hole 18, reducing its effective passage cross-sectional area. Even if the servo motor 22 rotates beyond the first rotation angle position, the valve hole 17 is separated from the communication hole 13 and the communication between the first elastic thin film chamber 11 and the chamber space 7 is cut off. However, the effective passage cross-sectional area of the orifice hole 15 decreases as its rotation angle increases.

FIG. 3 shows one embodiment of a control system for controlling the current supplied to servo motor 22. FIG. The servo motor 22 is supplied with current from a power supply circuit 25, and the current is controlled by a control signal output from a control device 26 to the power supply circuit 25.
The control device 26 receives information regarding the accelerator depression speed from an accelerator depression speed sensor 28 attached to the accelerator lever 27, and changes the power supply circuit according to the increase in the accelerator depression speed as shown in the flow chart shown in FIG. 25 controls the current of the power supply circuit 25 so that the duration of the current supplied to the servo motor 22 increases.

Next, one embodiment of the control procedure for the vibration isolating rubber device according to the present invention will be described in detail with reference to the flowchart shown in FIG. In the control based on this flowchart, the rotating shaft 23 of the servo motor 22 is positioned at the initial rotation angle position during steady operation or slow acceleration when the accelerator depression speed is less than a predetermined value, for example, 20 cm/sec. As a result, at this time, the valve hole 17 is aligned with the communication hole 13, the first elastic thin film chamber 11 and the chamber space 7 communicate with each other, and the pressure in the chamber space 7 is transferred through the valve hole 17 and the communication hole 13 to the first elastic thin film chamber 11 and the chamber space 7. It is introduced into the membrane chamber 11, which acts on one side of the elastic membrane 10. Therefore, at this time, the elastic thin film 10
is elastically deformed in response to changes in the internal pressure of the chamber space 7, suppressing increases in the internal pressure of the chamber space 7, and the vibration isolating rubber device generally maintains a spring constant relatively low, thereby effectively damping high frequency vibrations. When accelerating with an accelerator pedal speed of 20 cm/sec or more, the rotation shaft 23 of the servo motor 22
is brought to the first rotational angular position or a larger rotational angular position, the valve hole 17 is spaced apart from the communication hole 13, and the communication hole 13 is connected to the valve element 16.
, and communication between the first elastic thin film chamber 11 and the chamber space 7 is cut off. Therefore, at this time, the pressure of the chamber space 7 is no longer introduced into the first elastic thin film chamber 11, and the internal pressure fluctuations of the chamber space 7 are no longer suppressed by the elastic deformation of the elastic thin film 10. The fluid in the chamber space 7 flows through the throttle hole 15
The vibration isolating rubber device effectively damps low frequency vibrations due to the viscous damping effect caused by the fluid flow. The effective passage cross-sectional area of the throttle hole 15 is reduced by the valve element 16 as the accelerator depression speed is faster, that is, during rapid acceleration, and the viscous damping coefficient of the vibration isolating rubber device increases during rapid acceleration. Frequency vibrations are effectively damped.

Although the present invention has been described above in detail with reference to specific embodiments, the present invention is not limited thereto, and those skilled in the art will recognize that various embodiments are possible within the scope of the present invention. It should be obvious.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional view showing one embodiment of the vibration-proof rubber device according to the present invention, and FIG. 2 is a line taken along the line in FIG.
3 is a block diagram showing one embodiment of the control system for the vibration isolating rubber device according to the present invention, and FIG. 4 is a block diagram showing one embodiment of the control procedure for the vibration isolating rubber device according to the present invention. This is a flowchart. DESCRIPTION OF SYMBOLS 1, 2... Frame body, 3... Annular wall element, 4... Rod member, 5... Flange member, 6... Rubber-like elastic member, 7, 8... Chamber space, 9... Elastic thin film chamber member , 10... Elastic thin film, 11, 12... Elastic thin film chamber, 13, 14... Communication hole, 15... Throttle hole, 1
6... Valve element, 17, 18... Valve hole, 19... Long hole, 20... Rack tooth, 21... Mounting member, 22
... Servo motor, 23 ... Rotating shaft, 24 ... Pinion, 25 ... Power supply circuit, 26 ... Control device,
27... Accelerator lever, 28... Accelerator depression speed sensor.

Claims (1)

[Scope of utility model registration request] two frames, an annular wall element made of a rubber-like elastic body that extends between the two frames, connects them, and cooperates with the frames to define a chamber space; and a fluid for the chamber space. A vibration isolating rubber device comprising: a throttle passage through which the air enters and exits; an elastic thin film on one surface of which is subjected to the pressure of the chamber space through the communication passage; and a valve that opens and closes the communication passage.