JPH06117487A - Machine vibration isolator - Google Patents

Abstract

(57) [Summary] [Purpose] To effectively suppress the vibration of the machine M. [Structure] A plurality of air type bellows cylinders 10, 10 ...
The machine M is elastically supported via the, and a magnetic control device including iron pieces 21 and 22 and electromagnets 31 and 32 is installed in parallel for each bellows cylinder 10. The electromagnets 31, 32 are
A force is applied to the machine M in a direction of suppressing vertical vibration of the machine M.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vibration damping device for a machine, which is attached to a vibration type machine such as a machine tool or a loom to suppress vibration transmitted from the machine itself to the outside.

[0002]

2. Description of the Related Art Machine tools such as press machines and forging machines, and machines such as compressors and looms often generate excessive vibration during operation.

Therefore, when such a machine is installed, particularly strong foundation work is performed to prevent harmful vibrations from being transmitted to the outside, a kind of air spring called an air bellows cylinder, and a rubber vibration isolator. A method of elastically supporting the entire machine through elastic members such as is widely adopted.

In addition, a weight may be mounted on the machine in order to increase its weight and avoid resonance with the excitation force.

[0005]

According to such a conventional technique, the foundation work becomes complicated due to its special structure, and the vibration isolator such as the bellows cylinder suppresses harmful vibration over all frequencies. Therefore, there is a problem that it is not always possible to exhibit sufficient vibration damping performance.

In view of the problems of the prior art, an object of the present invention is to combine an air type bellows cylinder and a magnetic control device so that good vibration damping performance can be achieved without complicated foundation work. It is to provide a vibration damping device for a machine that can be realized.

[0007]

SUMMARY OF THE INVENTION In order to achieve the above object, the structure of the present invention has a plurality of pneumatic bellows cylinders whose internal pressure is controlled by an air adjusting circuit and which elastically supports a machine, and a bellows cylinder. The magnetic control device is equipped with a magnetic control device, and the gist of the magnetic control device is to exert a force on the machine in a direction of suppressing vertical vibration of the machine.

The magnetic control device may include an electromagnet and a control circuit for controlling the exciting current of the electromagnet according to the vertical displacement of the machine.

[0009]

According to the structure of the present invention, the plurality of bellows cylinders hold the machine horizontally at a predetermined height position and elastically support the machine by controlling the respective internal pressures by the air adjusting circuit. As a result, the vibration of the machine can be absorbed. In addition, the magnetic control device,
By applying a force in the direction of suppressing the vertical vibration of the machine, it is possible to absorb the vibration of the machine and avoid a situation in which the machine is in a resonance state.

If an electromagnet and a control circuit are used as the magnetic control device, the control circuit controls the exciting current of the electromagnet according to the displacement of the machine in the vertical direction, and controls the attraction force generated by the electromagnet. Therefore, it is possible to more effectively prevent the machine from resonating and becoming excessively vibrated.

[0011]

Embodiments Embodiments will be described below with reference to the drawings.

The vibration isolator of the machine comprises pneumatic bellows cylinders 10, 10 arranged at the four corners of the machine M and iron pieces 21, 21 arranged above and below the bases M1, M1 of the machine M.
..., 22, 22 ..., Electromagnets 31, 31 ..., 32, 32 ...
And (Fig. 1), each iron piece 21, 22, the electromagnet 3
Reference numerals 1 and 32 form a magnetic control device provided in parallel with each bellows cylinder 10.

The bellows cylinders 10, 10, ... Are arranged at the four corners of the bottom of the machine M and can elastically support the machine M as a whole. Each bellows cylinder 10
Support plates 12 and 13 are attached to the top and bottom of a lantern-shaped bellows body 11 made of a rubber-like elastic material (FIG. 2), and are installed on the floor via fixing bases 14 and 51. Further, each bellows cylinder 10 supports the total weight of the machine M via the support plate 12.

The iron pieces 21 and 22 are fixed to the upper surface and the lower surface of the base portion M1 of the machine M, respectively.

The electromagnets 31 and 32 are arranged above and below the base portion M1 of the machine M so as to face the iron pieces 21 and 22, respectively, via a U-shaped bracket 33 fixed to the upper surface of the fixed base 51. ing. The electromagnets 31, 32
The control circuit 34 supplies the exciting currents i1 and i2 to the motor.

A displacement sensor 41 is arranged near each bellows cylinder 10. The displacement sensor 41 can detect the vertical displacement x of the machine M with respect to the floor surface and output it as an electric signal. The displacement sensor 41 is attached to the floor surface via the base 41b and detects the distance to the dog 41a attached to the bottom of the machine M as the displacement x.
The output signal from the displacement sensor 41 is sent to the control circuit 34.

The bellows cylinders 10, 10, ... Are connected to an air source 16 via an air adjusting circuit 15 (FIG. 3). The air adjusting circuit 15 includes a two-port lower limit valve 15b interposed between the air source 16 and the bellows cylinder 10, and a two-port upper limit valve 15a branched and connected to the outlet side of the lower limit valve 15b. Air can be supplied to the bellows cylinder 10 via the lower limit valve 15b, and the air of the bellows cylinder 10 can be exhausted from the exhaust port 15d via the upper limit valve 15a. In addition, between the upper limit valve 15a and the exhaust port 15d,
A flow rate adjusting valve 15c is provided.

The bellows cylinders 10, 10, ... Can always keep the height position of the machine M constant even if the weight of the machine M varies, and can elastically support the machine M horizontally. That is, when the internal pressure of each bellows cylinder 10 is low and the machine M is below the lower limit position, first, the lower limit valve 15b is operated to supply air to the bellows cylinder 10. Therefore, bellows cylinder 1
0 extends upward, and when it reaches a predetermined position, the lower limit valve 15b closes and the supply of air is finished. Therefore, the bellows cylinders 10, 10, ... Balance the total weight of the machine M and keep the machine M at a predetermined height. Can be maintained.

Next, when the weight of the machine M fluctuates toward the lighter side, the bellows cylinder 10 further extends and reaches the upper limit position. At that time, the upper limit valve 15a operates,
The air in the bellows cylinder 10 is exhausted. This allows
The bellows cylinder 10 is shortened, the upper limit valve 15a is closed when the bellows cylinder 10 reaches a predetermined position, and the bellows cylinder 10 can stand still for a predetermined length.

Thereafter, similarly, each bellows cylinder 10
Is expanded and contracted by the air adjusting circuit 15 in accordance with the change in the weight of the machine M to horizontally hold the machine M at a predetermined height position and elastically support the machine M, so that the machine M
It is possible to prevent the vibration generated from being transmitted to the floor. .

On the other hand, when vibration occurs in the machine M, the displacement x detected by the displacement sensor 41 becomes vibrational according to the vertical movement of the machine. Therefore, the control circuit 34 controls the displacement sensor 41
It is possible to supply the excitation currents i1 and i2 to the electromagnets 31 and 32 so as to suppress the vertical vibration of the machine M by inputting the displacement x from

That is, when the displacement x oscillates above and below a predetermined value x = xo with respect to time t (FIG. 4), the control circuit 34 controls the section of x <xo for the upper electromagnet 31. In the above, an exciting current i1 which changes corresponding to the magnitude of the displacement x is supplied, and x> x for the lower electromagnet 32.
In the section of o, the exciting current i2 that changes corresponding to the magnitude of the displacement x is supplied (the same figure). On the other hand, the electromagnet 31,
32 generates an attractive force corresponding to the magnitudes of the exciting currents i1 and i2 to attract the iron pieces 21 and 22, respectively.
On the other hand, since an upward or downward attraction force can be exerted, the electromagnets 31, 32 at this time can exert a force on the machine M in a direction of suppressing vertical vibration of the machine M. Further, even if the machine M may resonate with its exciting force, the control circuit 34 increases the exciting currents i1 and i2 in accordance with the magnitude of the displacement x to cause the electromagnets 31 and 3 to move.
By increasing the suction force of 2, it is possible to suppress excessive vibration of the machine M, so that it is possible to effectively prevent the machine M from falling into a harmful resonance state.

In the above description, the bellows cylinders 10, 10 ... Attached to the bottom of the machine M can be used in any number depending on the weight of the machine M. Further, the magnetic control device at this time is preferably arranged corresponding to each bellows cylinder 10 including the displacement sensor 41.

[0024]

Other Embodiments The iron piece 21 and the electromagnet 31 arranged on the upper surface side of each base M1 of the machine M are replaced by a pair of permanent magnets repelling each other, and the iron piece 22 and the electromagnet 32 arranged on the lower surface side.
Can be replaced by a set of permanent magnets that attract each other. Since these permanent magnets can always exert a downward force on the machine M, it is equivalent to placing a weight on the machine M and can suppress vertical vibration of the machine M.

Further, in this embodiment, if the permanent magnets on the lower surface side are also repelled from each other, the permanent magnets at this time exert a force in a direction in which the vertical vibration of the machine M is positively suppressed as a whole. Therefore, the vibration damping effect can be more effectively exhibited.

The magnetic control device uses a permanent magnet for each bellows cylinder 10, an electromagnet 31,
32 and the one using the iron pieces 21 and 22 can be used together. The former can apply a kind of bias to the latter attractive force, so that the latter can reduce the maximum value of the required attractive force to be generated.
It is possible to reduce the size of 1, 32.

The magnetic control device according to each of the above-described embodiments suppresses the vertical vibration of the machine M. In addition to this, a device for suppressing the horizontal vibration of the machine M is added. May be added. This is, for example, an electromagnet 3
1 and the iron piece 21, and the electromagnet 32 and the iron piece 22 are arranged so as to face each other in the horizontal direction, and the displacement sensor 41
May detect the horizontal displacement in the linear direction formed by the electromagnets 31, 32 and the iron pieces 21, 22. Machine M
When the horizontal vibration is not limited to one direction, two or more magnetic control devices for suppressing the horizontal vibration are provided,
The electromagnets 31, 32, the iron pieces 21, 22, or the permanent magnets may be arranged in different directions at right angles to the horizontal direction or at large angles close to right angles. Among the horizontal vibration components of the machine M, the respective magnetic control devices use the electromagnet 3
Since it is possible to suppress components such as 1, 32 and the like in the arrangement direction, it is possible to exhibit even better vibration damping performance in combination with the magnetic control device that suppresses vertical vibration.

[0028]

As described above, according to the present invention, by arranging the air type bellows cylinder and the magnetic control device in combination, the bellows cylinder keeps the machine horizontal at a predetermined height position. Can be elastically supported to prevent the vibration of the machine from being transmitted to the outside, and the magnetic control device minimizes the vibration of the machine by exerting a force in the direction of suppressing the vertical vibration of the machine. Therefore, there is an excellent effect that good vibration damping performance can be realized without complicated foundation work.

[Brief description of drawings]

[Figure 1] Overall configuration diagram

FIG. 2 is an enlarged explanatory view of main parts.

[Figure 3] Air system diagram

[Fig. 4] Operation explanatory diagram

[Explanation of symbols]

 M ... Mechanical x ... Displacement i1, i2 ... Exciting current 10 ... Bellows cylinder 15 ... Air adjusting circuit 31, 32 ... Electromagnet 34 ... Control circuit

Claims (2)

[Claims] 1. An internal pressure is controlled by an air adjusting circuit,
Multiple pneumatic bellows cylinders that elastically support the machine,
A vibration control device for a machine, comprising: a magnetic control device provided in parallel with the bellows cylinder; the magnetic control device exerts a force on the machine in a direction of suppressing vertical vibration of the machine. 2. The vibration control system for a machine according to claim 1, wherein the magnetic control device includes an electromagnet and a control circuit that controls an exciting current of the electromagnet in accordance with a vertical displacement of the machine. apparatus.