JP5902038B2 - Travel guidance device - Google Patents

Description

The present invention relates to a mobile guide apparatus provided with the oil passage aperture apparatus Rio utilizing diaphragm oil passage to reduce the cross-sectional area of the downstream side from the upstream side of the upstream side and the downstream side communicate with each other in the oil passage is there.

  In a conventional movement guide device, an oil passage that supplies oil to a pocket of a hydrostatic bearing is provided in order to form an oil film between sliding surfaces between the guide body and the moving body (for example, Patent Document 1 below). See).

JP-A-10-199803

  In such an oil passage, it is a common practice to provide a throttle in order to stabilize the pressure in the oil pocket by limiting the flow rate supplied to the upstream side of the oil pocket of the hydrostatic bearing. However, if the cross-sectional area of the oil passage in the throttle is made too large to maintain the throttle flow rate, turbulence may occur in the oil passage in the throttle. The oil that flows out from the throttle to the oil pocket side may cause turbulent flow in the oil passage between the throttle and the oil pocket. The pressure in the oil pocket becomes unstable, and the movement resistance of the moving body with respect to the guide body also becomes unstable. As a result, machining accuracy is reduced in the machine tool.

This invention aims to provide a mobile guide device provided with an oil passage aperture apparatus Rio utilizing diaphragm oil passage to prevent oil turbulence as much as possible.

The present invention will be described with reference to the reference numerals of the drawings (FIGS. 1 and 2) of the embodiments described later .

In the movement guide device according to the first aspect of the present invention, the movable body (3) is supported on the guide body (2) via the hydrostatic bearing (5), and the movable body (3) is driven by the driving means (4). ) Is moved relative to the guide body (2). An oil passage (7) for supplying oil to the oil pocket (6) of the hydrostatic bearing (5) in order to form an oil film between the sliding surface (8) between the guide body (2) and the moving body (3). In addition, an oil passage throttle (9) having a narrow passage group (10) in which a plurality of narrow passages (13a, 13b) are arranged in parallel is connected to an upstream side and a downstream side of the oil passage (7). the has an oil passage throttling device is provided to reduce the cross-sectional area of the downstream side from the upstream side in communication with each other. According to the first aspect of the present invention, it is possible to prevent the occurrence of the turbulent flow of the oil flowing out from the oil passage restriction (9) to the oil pocket (6) side of the hydrostatic bearing (5) as much as possible in the movement guide device.

The mobile guide apparatus according to the invention of claim 2 that assumes the first aspect, a plurality of fine channels (13a, 13b) is directed to the oil pocket (6) from the upstream side to the downstream side of the oil passage (7) And extend linearly parallel to each other. According to the second aspect of the present invention, the oil passing through the narrow passages (13a, 13b) of the narrow passage group (10) can be easily discharged as rectification to prevent the occurrence of turbulence as much as possible.

The present invention can be significantly prevent the occurrence of oil pocket (6) flows out to the side oil turbulence throttle oil passage (9) from the hydrostatic bearing (5) in the moving guide device.

It is sectional drawing which shows schematically the movement guide apparatus provided with the hydrostatic bearing. It is a fragmentary sectional view showing roughly the oil way to a hydrostatic bearing. (A) is a perspective view schematically showing a narrow path group of throttles in an oil path, (b) is a longitudinal sectional view showing the narrow path groups of the throttle, and (c) is also a transverse sectional view. (D) is a partial expanded sectional view of (c).

Hereinafter, an oil passage throttle according to an embodiment of the present invention, an oil passage throttle device using the oil passage throttle, and a movement guide device using the oil passage throttle device will be described with reference to the drawings.
This movement guide device is applied, for example, when a machining table is moved and guided in a machine tool. As shown in FIG. 1, a moving body 3 constituting a machining table is provided on a guide body 2 mounted on a machine base 1. Is supported in a non-contact state via an oil film. Between the guide body 2 and the moving body 3, a linear motor 4 is provided as a driving means and a hydrostatic bearing 5 is provided. The hydrostatic bearing 5 is provided with a plurality of oil pockets 6 along the longitudinal direction perpendicular to the drawing sheet on both side surfaces and upper surface in the width direction across the linear motor 4. The linear motor 4 includes a stator 4 a made of a coil provided on the guide body 2 side and a mover 4 b made of a magnet provided on the moving body 3 side, and the moving body 3 is uniaxial with respect to the guide body 2. Along the longitudinal direction.

  As shown in FIG. 2, each oil pocket 6 of the hydrostatic bearing 5 is connected to an oil passage 7, and between the sliding surfaces 8 between the guide body 2 and the moving body 3 by the oil supplied from the oil passage 7. An oil film is formed on the surface. The guide body 2 is formed with oil discharge grooves 8 a communicating with the sliding surface 8 on both sides in the width direction across the linear motor 4. A throttle 9 for reducing the cross-sectional area downstream from the upstream side is detachably attached to the oil passage 7 so as to face the oil pocket 6 slightly upstream from the oil pocket 6.

  As shown in FIG. 3, the throttle 9 is disposed on the upstream side of the narrow passage group 10 that connects the upstream side and the downstream side of the oil passage 7 to each other, and interposed in the oil passage 7. And an inlet portion 11. A male screw portion 11 a is formed on the outer periphery of the inlet portion 11 of the throttle 9. A hexagonal rotation hole 11 b is formed on the inner periphery of the inlet portion 11 of the throttle 9. The narrow path group 10 has a plurality of narrow path pipes 13 which are bundled together and press-fitted into the holding pipe 12 and inserted. The holding tube 12 is attached to the inflow port portion 11 by welding or the like. The outer peripheral surface of the holding tube 12 has a gap with respect to the inner peripheral surface of the oil passage 7. In addition to the narrow passages 13 a in the narrow passages 13, narrow passages 13 b are also provided between the narrow passages 13 adjacent to each other in the holding tube 12. The narrow passages 13a and 13b in each narrow pipe 13 are communicated with the turning hole 11b of the inflow port portion 11, and are linearly parallel to each other from the upstream side to the downstream side of the oil passage 7 toward the oil pocket 6. And have the same channel diameter and the same channel length. The diameter and length of the flow path and the number of narrow pipes 13 can be appropriately set according to various conditions.

  A female screw portion 7a having a diameter larger than that of the restrictor 9 is formed in the opening of the oil passage 7 adjacent to the restrictor 9, and a set screw 15 fitted with a seal ring 14 is detachably screwed into the female screw portion 7a. The opening of the oil passage 7 is closed. The restrictor 9 is inserted into the oil passage 7 from the female screw portion 7 a of the opening, and the male screw portion 11 a of the inflow port portion 11 is screwed into the female screw portion 7 b formed in the oil passage 7. With the wrench inserted in the rotation hole 11b of the inflow port portion 11, the position of the throttle 9 can be adjusted by advancing and retreating with the female screw portion 7b and the male screw portion 11a.

Next, the squeezing action of the oil passage squeezing device used in such a movement guide device will be described.
In the oil passage 7, the oil flowing into the inlet portion 11 from the upstream side of the throttle 9 passes through the narrow passages 13 a and 13 b in the holding pipe 12 and flows out downstream of the throttle 9. The oil that passes through the narrow passages 13a and 13b is less likely to generate turbulent flow and is stable, so that the oil is likely to flow out from the throttle 9 to the oil pocket 6 side of the hydrostatic bearing 5 as rectification. Therefore, the pressure of the oil pocket 6 is stabilized, and the movement resistance of the moving body 3 with respect to the guide body 2 is also stabilized.

This embodiment has the following effects.
(1) In the throttle 9 of the oil passage restricting device provided in the movement guide device employing the hydrostatic bearing 5, the narrow passage group 10 in which a plurality of narrow passages 13a and 13b are arranged in parallel causes the oil passage 7 to Since the cross-sectional area on the downstream side from the upstream side is reduced while maintaining the throttle flow rate, it passes through the narrow passages 13a and 13b of the narrow passage group 10 and flows out from the throttle 9 to the oil pocket 6 side of the hydrostatic bearing 5. The oil is easily discharged as rectification, and the generation of turbulent flow can be prevented as much as possible.

(2) Since the plurality of narrow passages 13 are inserted into the holding tube 12 and bundled, the narrow passage group 10 in which the plurality of narrow passages 13a and 13b are arranged in parallel can be easily provided.
For example, the following embodiment may be configured as follows.

-Instead of the narrow path group 10 in which a plurality of narrow path pipes 13 are inserted and bundled into the holding pipe 12, a plurality of narrow paths may be provided through a single shaft to provide the narrow path group.
-About the narrow paths 13a and 13b in each narrow path pipe 13, it is good also as a mutually different flow path diameter.

  The oil path throttle device can be applied to other than the movement guide device that moves and guides the machining table in the machine tool. In addition to the movement guide device, the present invention can be applied to various devices that need to narrow the oil passage.

  DESCRIPTION OF SYMBOLS 2 ... Guide body, 3 ... Moving body, 4 ... Linear motor (drive means), 5 ... Static pressure bearing, 6 ... Oil pocket, 7 ... Oil path, 8 ... Sliding surface, 9 ... Restriction, 10 ... Narrow path group , 11 ... inflow port part, 12 ... holding pipe, 13 ... narrow pipe, 13a, 13b ... narrow path.

Claims (2)

In a movement guide apparatus in which a moving body is supported on a guide body via a hydrostatic bearing, and the moving body is moved relative to the guide body by a driving means, the gap between the sliding surface between the guide body and the moving body In order to form an oil film on the oil passage, an oil passage for supplying oil to the oil pocket of the hydrostatic bearing is provided with an oil passage throttle having a narrow passage group in which a plurality of narrow passages are arranged in parallel. A movement guide apparatus comprising an oil passage throttle device provided so as to communicate with an upstream side and a downstream side so as to reduce a cross-sectional area downstream from the upstream side . 2. The movement guide according to claim 1 , wherein in the oil passage restriction, the plurality of narrow passages are linearly extended in parallel to each other from the upstream side to the downstream side of the oil passage toward the oil pocket. apparatus.