JP4832385B2 - Attenuator bearing structure - Google Patents

Description

  The present invention uses, for example, an interlayer displacement of a structure caused by vibration energy such as an earthquake to make a relative reciprocating motion through a mounting member provided in the structure, and the relative reciprocating motion is turned into a rotational motion by a screw mechanism. The present invention relates to a bearing structure of a damping device that absorbs and attenuates the vibration energy by means of a screw damping portion by conversion and screw friction and a viscous damping portion by a viscous body.

2. Description of the Related Art Conventionally, as an attenuation device for attenuating vibration energy in an earthquake or the like, there is known a device having a kinetic energy conversion unit provided with a screw attenuation unit that converts a reciprocating linear motion into a rotational motion as described above (Patent Document 1). reference).
JP 2004-84845 A

  An example of the configuration of such a damping device 21 is, for example, as shown in FIG. 3, which includes a screw damping portion 22 and a viscous damping portion 23, and a nut 25 is an axial center on a cylindrical body 24 in the screw damping portion 22. The screw shaft 26 is inserted therethrough. The nut 25 and the screw shaft 26 are relatively moved in the axial direction at the time of an earthquake. Since the nut 25 is fixed and does not rotate, the screw shaft 26 linearly reciprocates and rotates.

  The end portion of the inner cylinder 27 that is rotatably supported in the viscous damping portion 23 is connected and fixed to the flange portion 26 a of the screw shaft 26. The inner cylinder 27 is rotatably supported inside by an outer cylinder 28, and a viscous body 29 is filled in a gap between the inner cylinder 27 and the outer cylinder 28 so that the inner cylinder 27 rotates. It has become.

  In the vicinity of the screw friction part 26b between the nut 25 and the screw shaft 26 in the screw attenuating part 22, heat is generated due to friction during an earthquake. Therefore, as shown in FIGS. Are provided at, for example, 24 locations at equal intervals in the circumferential direction in parallel with the axis. In this way, the heat generated in the screw friction portion 26b of the screw attenuating portion 22 is absorbed by the refrigerant flowing through the flow path 25a, and is radiated to the outside through the refrigerant tank and the heat radiating plate.

  However, in the damping device 21 of the conventional example, in the screw friction portion 26b in the rotational motion conversion portion in the net 25 and the screw shaft 26, due to the generation of local frictional heat, the damping capability is reduced or the screw portion is expanded. Burn-in becomes a problem. That is, as shown in FIG. 4B, in the bearing portion a, the temperature of the portion c where the refrigerant of the support bearing 32 flows is lowest than that of the surroundings. Therefore, in the event of an earthquake, the temperature rises in the range of the threaded portion b of the screw shaft 26 and heat is transferred to the surroundings. However, considering the clearance between the screw shaft 26 and the support bearing 32, the support bearing 32 of the bearing portion a is Since the outer diameter of the screw shaft 26 in the coaxial receiving portion a expands without expanding, the temperature may rise rapidly due to friction due to an interference fit and may be locally seized. If the bearing portion is present on the flow path of the refrigerant, there is a difference in thermal influence, resulting in inconvenience. The bearing structure of the damping device according to the present invention has been proposed in order to solve such a problem.

  The gist for solving the above-mentioned problems of the bearing structure of the damping device according to the present invention is to reciprocate the inter-layer displacement generated in the structure by vibration energy through the mounting member provided in the structure. The relative reciprocating motion of the part, the relative reciprocating motion is converted into rotational motion by the screw mechanism, and the screw damping portion that generates friction damping, and the rotational damping that attenuates energy by the resistance force applied to the rotational motion An outer peripheral surface of the screw shaft between the screw portion of the screw shaft in the screw mechanism portion and a bearing portion that is rotatably supported at both ends of the screw portion. In other words, a non-contact portion that is an annular space portion having a required thickness is provided.

A non-contact portion on one side of both non-contact portions at both ends of the screw portion is drilled in a flange portion of the nut along a radial direction of the nut screwed to the screw shaft, and has one end portion on an inner wall surface. There is a supply flow path for refrigerant supply that is open, and there is an annular groove for refrigerant distribution that is engraved in the circumferential direction in communication with one end of the supply flow path, and an inner opening end of the annular groove for refrigerant distribution A ring-shaped bush having a gap between the outer diameter and the inner peripheral surface of the screw shaft;
The bushing seals the inner open end of the annular groove for refrigerant distribution by fitting with a tightening margin, for example, cold fitting, press fitting, etc .;
Is included.

According to the bearing structure of the damping device of the present invention, when the screw portion of the screw shaft generates heat due to friction during an earthquake, there are non-contact portions at both ends of the screw portion, and the outer diameter portion of the screw in this range is thermally expanded. Even so, there is no bearing portion such as a bearing member or a nut, and therefore no seizure due to an interference fit occurs. Therefore, stable attenuation performance of the attenuation device is ensured.
The clearance of the bearing portion can be set small, the distance between the bearing portions is further increased, the distance between the fulcrums is widened, the tilt of the screw shaft is reduced, and the guideability is improved.

In addition, the non-contact portion reduces the temperature of the screw shaft and the nut due to the heat dissipation effect therebetween, and the damping device can cope with long-time shaking due to an earthquake.
A non-contact portion on one side of both non-contact portions at both ends of the screw portion is drilled in a flange portion of the nut along a radial direction of the nut screwed to the screw shaft, and has one end portion on an inner wall surface. Since there is a supply flow path for supplying the refrigerant, the bearing position does not exist on the refrigerant flow path, and an interference fit can be avoided. If there is a bearing portion on the refrigerant flow path, the thermal expansion of the bearing portion is suppressed by the refrigerant, and on the other hand, the screw shaft thermally expands due to friction, so that there is no gap in the bearing portion, and a hugging state occurs suddenly. Inconvenient situations have occurred, such as a large increase in damping force and abnormal heat generation. Such a problem can be solved by providing the non-contact portion in the present invention.

  As shown in FIG. 1, in the bearing structure A of the damping device according to the present invention, the inter-layer displacement generated in the structure by vibration energy is set as the relative reciprocating motion of the reciprocating motion part via the mounting member provided in the structure. The relative reciprocating motion is rotated by the screw mechanism portion of the screw shaft 1, the nut 2 having a female screw portion fitted to the screw shaft 1, and the bearings 3 and 4 that rotatably support the screw shaft 1. It has been converted.

  The screw shaft 1 and the nut 2 constitute a screw mechanism, which converts to a rotational motion and generates friction damping. Between the screw portion 1a of the screw shaft 1 in the screw mechanism portion and the bearing portions 3 and 4 that are rotatably supported by both ends of the screw portion 1a, an annular ring having a required thickness from the outer peripheral surface of the screw shaft 1 The non-contact part 5 which is a space part is provided. As shown in FIG. 1, the non-contact part 5 exists between the screw part b and the bearing part a.

  As shown in FIGS. 1 and 2, the non-contact portion 5 a on one side of both non-contact portions at both ends of the screw portion 1 a extends along the radial direction of the nut 2 screwed into the screw shaft 1. There is a supply channel 6 for supplying a refrigerant that is perforated in the flange portion 2a of the nut 2 and has one end portion 6a opened on the inner wall surface, and is communicated with the one end portion 6a of the supply channel 6 and is engraved in the circumferential direction. There is an annular groove 7 for refrigerant distribution, the inner opening end 7a of the annular groove 7 for refrigerant distribution is sealed with an outer peripheral surface 8a, and between the outer diameter of the screw shaft 1 and the inner peripheral surface 8b. A ring-shaped bush 8 having a gap is provided.

  As shown in FIG. 4 (A), the coolant distribution annular groove 7 is, for example, 24 cooling flow channels at equal intervals in the circumferential direction along the axis d in parallel with the screw portion 1a. One end of the path 9 (corresponding to the flow path 25a shown in FIG. 4) is connected and connected. The bush 8 seals the inner opening end of the refrigerant distribution annular groove 7 by cold fitting or the like. Thus, the inner opening end 7 a of the refrigerant distribution annular groove 7 is surely sealed by outward stress in the radial direction of the bush 8.

  In this way, in this bearing structure A, the non-contact parts 5 are provided on both sides of the heat generating screw part b to keep the bearing part a away from the heat generating part (screw part 1a), and the bearing part a on the cooling channel. Is not provided so that an interference fit does not occur. Thus, the span of the bearing portions a, a of the screw shaft 1 becomes longer, the inclination of the screw shaft 1 becomes smaller, and the clearance between the screw shaft 1 and the bearing portion a can be set smaller.

It is a longitudinal cross-sectional view of the bearing structure A of the damping device according to the present invention. It is the detailed sectional view which expanded a part of bearing structure A of the damping device of the present invention. It is a longitudinal cross-sectional view which shows the bearing structure of the attenuation device 21 which concerns on a prior art example. They are an expanded sectional view (A) which shows the bearing structure of the conventional example, and a front view (B).

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Screw shaft in bearing structure of damping device, 1a Thread part,
2 nuts, 2a buttocks 3, 4 bearings,
5 Non-contact part, 5a Non-contact part,
6 supply flow path, 6a one end,
7 Annular grooves for refrigerant distribution,
8 bush, 8a outer peripheral surface,
8b inner peripheral surface,
9 Channel, 7a Open end,
21 Attenuator,
22 Screw attenuation part,
23 Viscous damping part,
24 cylinders,
25 nut, 25a flow path,
26 screw shaft, 26a collar,
26b screw friction part,
27 inner cylinder,
28 outer cylinder,
29 Viscous material,
30 refrigerant,
31 piston,
a bearing part b thread part
d axis.

Claims (3)

Interlayer displacement generated in the structure by the vibration energy is converted into a reciprocating motion of the reciprocating motion part via the mounting member provided in the structure, and the relative reciprocating motion is converted into a rotational motion by the screw mechanism and friction. In the screw mechanism portion of the attenuation device, which includes a screw attenuation portion that generates attenuation and a rotation attenuation portion that attenuates energy by a resistance force applied to the rotational motion,
A non-contact portion that is an annular space portion having a required thickness from the outer peripheral surface of the screw shaft between a screw portion of the screw shaft in the screw mechanism portion and a bearing portion that is rotatably supported at both ends of the screw portion. Is provided,
A bearing structure of a damping device characterized by The non-contact part on one side of both non-contact parts at both ends of the screw part,
There is a supply flow path for supplying a refrigerant that is perforated in the flange portion of the nut along the radial direction of the nut that is screwed onto the screw shaft, and that has one end opened on the inner wall surface.
There is an annular groove for distributing refrigerant that is engraved in the circumferential direction in communication with one end of the supply flow path,
A ring-shaped bush having a gap between an outer diameter and an inner peripheral surface of the screw shaft, the inner opening end of the annular groove for refrigerant distribution being sealed with an outer peripheral surface;
The bearing structure of the damping device according to claim 1. The bush has sealed the inner opening end of the annular groove for refrigerant distribution by fitting with a tightening margin,
The bearing structure of the damping device according to claim 2.

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