JPS595401A - Vibration isolator - Google Patents

Abstract

PURPOSE:To eliminate an unstable element of an attenuation characteristic of vibration, by providing a winding which is fixed to a body and is interlinked with a magnetic field in an air-gap, and a spring for holding a base seat to the body, and terminating both ends of the winding by an electric circuit network. CONSTITUTION:A winding 8 is fixed to a body 1 by use of a bobbin 6. A magnet 10 and two yokes 9, 11 for forming a magnetic path are fixed to a base seat 13. The winding 8 moves in the air-gap of this magnetic path, and the base seat is held to the body by a spring 7. Both ends of the winding 8 are terminated by an electric circuit network 12. In this state, when constants decided by intensity of a magnet, the number of turns of the winding, etc., the impedance of the circuit network and the winding, respectively, a constant of the spring, and mass of the body are denoted by k1, k2, and Z1, Z2, and k3, and (m), respectively, a kinematic equation of the body in case when the base seat 13 is fixed is given by the equation. The equation indicates that a wide attenuation characteristic is obtained by setting Z2. Accordingly, an unstable element of the attenuation characteristic can be eliminated.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a vibration isolating mechanism used in record players and the like, which functions to reduce the transmission of vibration between the device and the environment in which the device is placed.

FIG. 1 is an example of a conventional general vibration isolator.

The leg seat 4 is held from the main body 1 by a spring 2 and a damper 3, and vibrations of the stand 5 are attenuated and transmitted to the main body 1. The vibration damping characteristics are mainly determined by the characteristics of the Danzo 3, but they vary greatly due to variations in the material and deterioration.

The present invention has been made in order to eliminate the above-mentioned unstable factors in the damping characteristics.

FIG. 2 shows an embodiment of the present invention. A winding 8 is fixed to the main body 1 using a bobbin 6. Two yokes 9 and 11 that form a magnetic path with the magnet 10 are fixed to the leg seat 13. The winding 8 moves within the gap of the magnetic path, and the leg seat is held in the main body by a spring 7. Winding 8
is terminated at both ends by an electrical network 12.

Now, when the leg seat and the main body have a relative velocity τ, the electromotive force of the winding 8 is expressed by the following equation.

V8: 1τ (1) Here, 1 is a constant determined by the strength of the magnet, the number of turns per winding, etc. At this time, since the winding 8 is terminated by the circuit network 12, a current expressed by a linear equation flows.

■. =■e/(Z, +22) (2) Here, zl is the impedance of the circuit network 12, and z2
is the impedance of the winding itself. ■Winding 8 by
receives a force expressed by the following equation 4 from the magnetic field.

F=-2Io(3) Here, k2 is a constant determined by the same elements as 1. From (1) to (3), −k k υ F = + 2 / (z, +z2) (4) If the mass of the main body is m and the constant of spring 7 is 3, the motion when the leg seat is fixed is The equation is given by x m d P after 2+ to 1 to 2 z1+22) 1/dt to 5X00 (5). Equation (5) shows that a wide range of damping characteristics can be obtained by setting z2.

By using the present invention as described above, it is possible to easily construct a vibration isolating device that has little initial variation and little change over time, and whose vibration absorption characteristics can be set depending on the object of use.

[BRIEF DESCRIPTION OF THE DRAWINGS] Fig. 1 shows a conventional vibration isolator, Fig. 2 shows an embodiment of the present invention, and Fig. 3 shows an example of the configuration of the circuit network shown in Fig. 2. FIG. ]...Body, 2...Spring, 3...Damper,
4... Leg seat, 5... Stand, 6... Bobbin, 7...
・Spring, 8...Winding, 9.11...Yoke,
10...Magnet, 12...Circuit network, 13...
Leg seat, 14.18...terminal, 15.16...resistance,
17... Capacitor. Figure 1 Figure 2 Figure 3

Claims (1)

[Claims] In a vibration isolating device used as a support leg for a cord player, etc., there is a magnet fixed to a leg seat serving as the leg, a yoke that forms a magnetic path with an air gap together with the magnet, and a yoke that is fixed to the main body and located within the air gap. A winding interlinked with the magnetic field of
A vibration isolating device comprising a spring for maintaining a mechanical balance between the main body and the leg seat, and having both ends of the winding terminated by an electric circuit network.