VIBRATION ISOLATION DEVICE

• US 20070052143A1
• Filed: 09/06/2006
• Published: 03/08/2007
• Est. Priority Date: 09/07/2005
• Status: Active Grant

• Current Assignee: Unirock Co., Ltd.
• Original Assignee: Unirock Co., Ltd.
• Inventors: Tsuchiya, Takahiro, Emoto, Shigeo
• Granted Patent: US 8,006,964 B2
• Time in Patent Office: Days
• US Class Current: 267/140.140
• CPC Class Codes: F16F 15/046 using combinations of springs of different kinds F16F15/085 takes precedence

Abstract

A vibration isolation device can more effectively restrain vibration in the horizontal direction rather than in the vertical direction with a simple construction. In addition, vibration of a frequency of a machine mode caused by an internal structure of the vibration isolation device is reduced with a simple construction.

Claims

1. A vibration isolation device comprising:

a lower plate fixedly arranged horizontally;

an upper plate arranged horizontally above this lower plate with a predetermined interval and supporting a supported object;

a viscoelastic body connecting the lower plate and upper plate to each other;

and compression coil springs arranged between the lower plate and upper plate in the vertical direction, wherein the coil springs are arranged at positions of a plurality of pairs with an equiangular interval in point symmetry around a center line, extending vertically from the lower plate toward the upper plate, and each comprised by a coil spring with a free length longer than an outer diameter, and the viscoelastic body is arranged axisymmetrically with respect to the center line of the upper plate and lower plate and inclined with respect to this center line, and wherein the viscoelastic body is arranged in a hollow cylinder portion extending in its longitudinal direction and having its upper end fixed to one of the lower plate and the upper plate, with the lower end arranged opposite to an inclined face of a receiving mount on the upper plate or the lower plate side and compressed/adjusted in the longitudinal axis direction by an adjusting screw capable of insertion to/removal from the hollow cylinder portion, and a receiving plate mounted to an end face of the lower end is pulled by a tension spring and housed into the hollow cylinder portion.

2. The vibration isolation device according to claim 1, wherein the receiving plate mounted at the lower end of the viscoelastic body is opposed to the inclined face of the opposing receiving mount when the supported object is loaded on the upper plate.

3. The vibration isolation device according to claim 2, wherein the receiving plate mounted at the lower end of the viscoelastic body is adjusted by the adjusting screw while the supported object is loaded on the upper plate and brought into contact with the inclined face of the opposing receiving mount.

4. The vibration isolation device according to claim 2, wherein the receiving plate mounted at the lower end of the viscoelastic body is separated from the inclined face of the opposing receiving mount in the state where the supported object is not loaded on the upper plate.

5. The vibration isolation device according to claim 2, wherein a plate is provided perpendicularly to the inclined face of the receiving mount at the upper part thereof opposing the receiving plate mounted on the end face of the lower end of the viscoelastic body.

6. The vibration isolation device according to claim 1, wherein the receiving plate mounted on the end face of the lower end of the viscoelastic body is pivotally supported by a hinge at the upper part with respect to the inclined face of the opposing receiving mount.

7. The vibration isolation device according to claim 6, wherein the receiving plate mounted at the lower end of the viscoelastic body is brought into contact with the inclined face of the opposing receiving mount when the supported object is loaded on the upper plate.

8. The vibration isolation device according to claim 6, wherein the receiving plate mounted at the lower end of the viscoelastic body is rotationally moved around the hinge in the state where the supported object is not loaded on the upper plate and the lower part is separated from the inclined face of the opposing receiving mount.

9. The vibration isolation device according to claim 8, wherein the hollow cylinder portion is provided with a notch portion to prevent contact of the viscoelastic body when the receiving plate is rotationally moved around the hinge and the lower part is floated.

14. The vibration isolation device according to claim 3, wherein the receiving plate mounted at the lower end of the viscoelastic body is separated from the inclined face of the opposing receiving mount in the state where the supposed object is not loaded on the upper plate.

15. The vibration isolation device according to claim 3, wherein a plate is provided perpendicularly to the inclined face of the receiving mount at the upper part thereof opposing the receiving plate mounted on the end face of the lower end of the viscoelastic body.

16. The vibration isolation device according to claim 7, wherein the receiving plate mounted at the lower end of the viscoelastic body is rotationally moved around the hinge in the state where the supported object is not loaded on the upper plate and the lower part is separated from the inclined face of the opposing receiving mount.

10. A vibration isolation device comprising:

a lower plate fixedly arranged horizontally;

an upper plate arranged horizontally above the lower plate with a predetermined interval and supporting a supported object;

an intermediate plate arranged between the lower plate and upper plate horizontally and provided with a through hole at the center;

a single first viscoelastic body passing through the through hole of the intermediate plate and connecting the lower plate and upper plate to each other;

at least three or more first compression coil springs arranged around the viscoelastic body so that they extend in the vertical direction between the lower plate and intermediate plate; and

at least three or more second compression coil springs extending in the vertical direction at the same positions as the first compression coil springs with respect to the horizontal direction between the intermediate plate and upper plate, the corresponding first and second compression coil springs being arranged in point symmetry or with an equiangular interval around a center line of the first viscoelastic body, respectively,

wherein a plurality of second viscoelastic bodies are arranged between the lower plate and intermediate plate at positions not interfering with the first compression coil springs with respect to the horizontal direction and extending in the vertical direction so as to connect the lower plate and the intermediate plate to each other.

11. The vibration isolation device according to claim 10, wherein said second viscoelastic bodies are arranged in an area between the first compression coil springs.

12. The vibration isolation device according to claim 10, wherein said second viscoelastic bodies are arranged within at least a part of the first compression coil springs.

13. The vibration isolation device according to claim 10, wherein said second viscoelastic bodies are formed from a material in a glass transition zone under an operating temperature condition.

17. The vibration isolation device according to claim 11, wherein said second viscoelastic bodies are arranged within at least a part of the first compression coil springs.

18. The vibration isolation device according to claim 11, wherein said second viscoelastic bodies are formed from a material in a glass transition zone under an operating temperature condition.

19. The vibration isolation device according to claim 12, wherein said second viscoelastic bodies are formed from a material in a glass transition zone under an operating temperature condition.