Throttle unit and a static pressure bearing device equipped with the throttle unit, and a method of manufacturing a grooved block

Abstract

A throttle unit is equipped with a grooved block including at least one minute groove formed on a plane surface, and an opposite block having a plane surface which is opposite to the minute groove. The grooved block and the opposite block are detachably joined so as to be opposite to each other. A throttle fluid path is formed by the minute groove and the plane surface of the opposite block. At least one surface of each of the minute groove is constituted by a curved surface or an inclined surface that is inclined with respect to the plane surface of the grooved block.

Description

CROSS-REFERENCE TO RELATED APPLICATION[0001]This application is based upon and claims the benefit of priority from Japanese Patent Application No. 2016-076039 filed on Apr. 5, 2016, the contents of which are incorporated herein by reference.BACKGROUND OF THE INVENTION[0002]Field of the Invention:[0003]The present invention relates to a throttle unit and a static pressure bearing device equipped with the throttle unit, and a method of manufacturing a grooved block.[0004]Description of the Related Art:[0005]In machine tools, as a guide device for a table having a linear motion axis or a rotational axis, static pressure bearings are used. In a static pressure bearing, in a case of a structure with a linear motion axis, for example, a static pressure pocket is formed on a bearing surface of a slide or a guide, and a working fluid such as oil or air is supplied to the static pressure pocket. The slide floats above the guide as a fixed portion by the static pressure of the working fluid, ...

AI Technical Summary

Benefits of technology

The present invention provides a throttle unit and a static pressure bearing device equipped with the throttle unit, and a method of manufacturing a grooved block. The invention allows for accurate groove machining and obtains an accurate groove shape by measuring the groove depth and width using a microscope. The throttle unit reduces the weight of parts, has a compact structure, decreases manufacturing steps and costs, is highly reliable, and easy to disassemble and clean.

Problems solved by technology

Problems of the needle throttle unit include the following points: the man hours for assembling the unit are large since the structure for incorporating the needle is complicated; the individual differences in the restriction strength are large since the variety of inner diameter errors of the respective needles is likely to affect the restriction strength; the unit has low reliability since the needle tends to fall off, and thus the restriction strength may change over time; due to a limit to the needle thinness, a thin needle is required to be long and have a special shape, for securing a certain degree or more of the restriction strength, so that the cost is high for preparing such a needle; and it is difficult to clean the unit when the needle is clogged with foreign material or the like.

Problems of the screw throttle unit include the following points: The number of parts or components is large and the structure of the unit is complicated, so that man hours for assembling are large; Precise adjustment is indispensable and the individual differences in the restriction strength become large depending on the adjustment state; The restriction strength may change in time due to looseness of the screw; The cost is high because of the large number of components; And it is difficult to clean the unit when the unit is clogged with foreign material or the like.

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