KR20130055517A - Hydrostatic gas bearing and linear motion guide device using thereof - Google Patents

Abstract

PURPOSE: A static pressure gas bearing and a direct-acting guiding device using the same are provided to obtain the static pressure gas bearing and the direct-acting guiding device using the static pressure gas bearing capable of mass production at low costs. CONSTITUTION: A static pressure gas bearing(1) comprises a base and a bearing body(3). The base includes a base unit, a cylindrical protrusion, and an air supply path. The cylindrical protrusion is installed in the outer periphery of one surface of the base unit. The bearing body includes a concave portion, a ring-shaped concave groove(20), and a plurality of air blowout holes(25). The bearing body press-fits into the outer periphery The outer periphery of the bearing body is press-fitted into the inner surface of the cylindrical protrusion. The bearing body is adhered to a press-fitting unit, thereby being integrated with the base.

Description

Hydrostatic gas bearing and linear motion guide device using this constant pressure gas bearing

The present invention relates to a constant pressure gas bearing and a linear motion guide device using the constant pressure gas bearing.

In precision machine tools and semiconductor exposure apparatuses, it is required to precisely position workpieces such as machining tools and substrates. For this reason, a linear motion guide device equipped with a static pressure gas bearing with little friction in the positioning device of the machining tool or the workpiece is used. In such a linear motion guide device, a pressurized fluid is interposed between a movable table as a mounting table of a workpiece and a guide rail as a guide member, and the movable table is moved in a non-contact manner with respect to the guide rail.

The type of aperture of the air jet of the hydrostatic gas bearing mounted on the linear motion guide device includes a porous aperture, a surface aperture, an orifice aperture, an autogenous aperture, and the like. We are using while.

For example, Patent Literature 1 discloses a static pressure bearing pad which is fixed to one of a supported member or a support, and supports the support freely by pressurized air supplied to the bearing surface via the bearing member. As a member, the carbon graphite type material of the kind whose diameter of a raw material particle is substantially uniform, and the uniformity of an open pore is obtained is described.

Further, Patent Document 2 discloses a gas bearing device which realizes high damping while maintaining relatively high rigidity, wherein gas is supplied through an orifice to a bearing gap between two substantially parallel bearing surfaces facing each other and both bearing surfaces. A gas bearing device with at least one gas duct is proposed.

In addition, Patent Literature 3 includes a surface diaphragm comprising a base material made of a porous body and a porous plate bonded onto the base material and prepared by adjusting the diameter and distribution of the through holes so as to have a desired air permeation amount in advance. A constant pressure gas bearing has been proposed, which ejects gas through and supports the supported member by the positive pressure.

Patent Document 1: Japanese Patent Application Laid-Open No. 63-231020 Patent Document 2: Japanese Patent Application Laid-Open No. 2006-510856 Patent Document 3: Japanese Patent Application Laid-Open No. 2001-56027 Patent Document 4: Japanese Unexamined Patent Publication No. 2008-82449

The conventional hydrostatic gas bearings can realize ultra low friction, ultra high precision and ultra high speed, but are inevitably expensive due to the use of high-strength metals and ceramics as a bearing material and high precision grinding finish. there is a problem.

However, ultra-low friction, ultra-high precision, and ultra-high speed motion are not required, but for example, when a non-contact conveyance of an article such as a liquid crystal screen or horizontal movement of the article without causing a temperature change, the use of a constant pressure gas bearing can While the configuration has the advantage of being simplified, etc., since the static gas bearing itself is expensive, it is not widely used for the purpose.

In order to provide an inexpensive static pressure gas bearing that can be utilized in various fields in view of the above circumstances, the present applicant first has a plurality of air outlets having a magnetic aperture shape or an orifice aperture shape on an upper surface thereof, and a plurality of air outlets on a lower surface thereof. A hydrostatic gas bearing has a bearing which is made of a resin bearing member having an air supply groove communicating with the base, and a base having a supply hole connected to the lower surface of the resin bearing member so as to cover the air supply groove and communicating with the air supply groove. (Patent Document 4).

According to the hydrostatic gas bearing described in this patent document 4, the resin bearing member constituting the hydrostatic gas bearing can be formed by injection molding using a mold, which eliminates the need for mechanical processing and at the same time the structure of the base. The static pressure gas bearing can be assembled by simply joining the resin bearing member and the base only by forming the air supply port communicating with the resin bearing member, and mass production of the static pressure gas bearing becomes possible, and the cheap static gas bearing can be obtained. It can be provided.

However, since the air jet port in the hydrostatic gas bearing of patent document 4 is formed by injection molding, it becomes the shape of the magnetic diaphragm or orifice diaphragm of the comparatively large diameter whose diameter is about 0.2-0.4 mm, and the air supply from the air jet port is carried out. The amount of ejection is too high, and there is a possibility of causing vibration. Therefore, improvement is needed to put it into practical use.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described various aspects, and an object thereof is to provide a low-pressure static pressure gas bearing capable of mass production and a linear motion guide device using the constant pressure gas bearing.

The hydrostatic gas bearing of the present invention has a cylindrical protrusion protruding from the outer periphery of one side of the base portion, one end of the base portion, and one end opening at one side of the base portion, while the other end opens at the outer peripheral surface of the base portion. A bearing base having an air supply passage; The annular recess formed in one surface facing one side of the base portion, the annular recess opened in the other surface, and the annular recess in one end thereof, and at the other end, the annular recess in the annular recess. A bearing body made of a synthetic resin having a plurality of air blowing holes as an open magnetic aperture; the bearing body fits an outer circumferential surface adjacent to one surface to an inner surface of a cylindrical protrusion of a base portion, and at the fitting portion Bonded to the bearing base, the annular recess has a width of at least 0.3 mm and a depth of at least 0.01 mm, the air jet hole has a diameter of at least 30 μm at one end, and the annular recess and the annular recess It is characterized by forming a magnetic aperture among the.

According to the hydrostatic gas bearing of the present invention, a bearing body made of a synthetic resin fits an outer circumferential surface adjacent to one surface to an inner surface of a cylindrical protrusion of a base portion, and is bonded by an adhesive at the fitting portion and integrated into a bearing base. In addition, the bearing body made of synthetic resin is connected to the annular concave groove opened at the other side and the annular concave groove at one end, and at the other end, it has a plurality of air blowing holes opened to the annular concave portion. The groove has a width of at least 0.3 mm and a depth of at least 0.01 mm, the air jet hole has a diameter of at least 30 μm at one end thereof, and forms a magnetic aperture between the annular recess and the annular recess, Since the annular recess and the plurality of air blowing holes are formed without machining, mass production is possible. High cost production is possible.

In a preferred example, the annular recess has a width of 0.3-1.0 mm or 0.3-0.7 mm and a depth of 0.01-0.05 mm or 0.01-0.03 mm, and the air jet hole has a diameter of 30-120 μm at one end thereof. have.

Each of the annular recess and the air blowing hole is preferably formed by laser processing. The laser for processing is selected from carbon dioxide gas lasers, YAG lasers, UV lasers, excimer lasers and the like.

If each of the annular concave grooves and the air blowing holes is formed by laser processing, these can be formed instantaneously as compared with machining such as cutting and the like, and mass production is possible as well as inexpensive production.

In the hydrostatic gas bearing of the present invention, a spherical hydraulic concave portion may be formed on the other surface of the bearing base. The spherical hydraulic concave portion may be composed of a truncated conical concave portion or a concave spherical surface portion opened from the other side thereof, and these spherical hydraulic concave portions may be directly formed on the other side of the bearing base.

In the hydrostatic gas bearing of the present invention, a cylindrical recess is formed on the other surface of the bearing base to open at the other surface, and the fitting member is fitted and fixed to the cylindrical recess. The hydraulic concave portion may have a conical face formed on the fitting member while opening at one surface of the fitting member on the other side of the bearing base.

In the hydrostatic gas bearing of the present invention, a cylindrical recess is formed on the other surface of the bearing base to open at the other surface, and the fitting member is fitted and fixed to the cylindrical recess. The hydraulic concave portion may have a concave spherical surface formed in the fitting member while opening at one surface of the fitting member on the other side of the bearing base.

In a hydrostatic gas bearing having a spherical hydraulic concave on the other side of the bearing base, the spherical ball of the ball stud is placed in sliding contact with the spherical hydraulic concave, for example, to automatically align the spherical rotation to the hydrostatic gas bearing. alignment) function may be added.

In the hydrostatic gas bearing of the present invention, in addition to the annular concave groove, the bearing body has a large diameter annular concave groove which is formed on the other surface and surrounds the annular concave groove outside the annular concave groove. A plurality of first radial concave grooves in which one end opens in the annular concave groove, and the other end is opened in a large diameter annular concave groove, and a small diameter annular concave groove formed inside the annular concave groove. And a plurality of second radial concave grooves in which one end is opened in the annular concave groove and the other end is open in the small diameter annular concave groove. The annular concave groove and the first and second radial concave grooves may be formed on the other surface of the bearing body.

The hydrostatic gas bearing with this automatic alignment function is suitable for use in a linear guide device as a positioning device for the workpiece. That is, the linear motion guide device provided with the hydrostatic gas bearing of the present invention has a cross section having an upper plate facing the upper guide surface and a pair of side plates facing both the guide surfaces on the outer side of the guide member having the upper guide surface and the both guide surfaces. The movable table of the shape | shape is arrange | positioned, The ball stud is installed in the inner surface of each of the lower surface and the side plate of the upper surface of the movable table, respectively, facing a sphere inward, and the upper guide surface and both sides of the ball stud and the guide member. The hydrostatic gas bearing may be disposed between the guide surfaces so as to make the concrete hydraulic recess slide contact the spheres of the ball stud and face the bearing body to the upper guide surface and both guide surfaces of the guide member.

According to the linear motion guide device, the compressed air is injected from the plurality of air blowing holes of the bearing body to the upper guide surface and the both guide surfaces of the guide member, whereby the movable table is formed by an air lubrication film formed between the bearing body and the upper guide surface and the both guide surfaces. It can be held in a non-contact state with respect to the upper guide surface and both guide surfaces. In addition, if the bearing clearance between the bearing body and the upper guide surface and both guide surfaces is non-uniform, a pressure difference occurs in each of the bearing gaps, and the pressure difference bearing is automatically aligned in a direction in which the bearing clearance becomes uniform due to the pressure difference. And a state parallel to both guide surfaces. For this reason, the precision of parts, such as the parallelism and the squareness, of a guide member and a movable table can be made into comparatively coarse precision, and the low cost linear motion guide apparatus can be provided in addition to the low cost of the said hydrostatic gas bearing itself.

In the hydrostatic gas bearing of the present invention, the bearing body is preferably formed of thermoplastic synthetic resin such as polyacetal resin, polyamide resin, polyphenylene sulfide resin, and the bearing base is polyacetal resin, polyamide resin, Thermoplastic synthetic resins such as polyphenylene sulfide resins or reinforcing filler-containing thermoplastic synthetic resins containing 30 to 50 mass% of glass fibers, glass powders, carbon fibers or inorganic fillers, or aluminum or aluminum alloys. It is preferable. These synthetic resin bearing bodies and bearing bases may be formed by machining a synthetic resin material or may be formed by injection molding using a mold.

According to the present invention, it is possible to provide a static pressure gas bearing which can be mass-produced and inexpensive and a linear motion guide device using the constant pressure gas bearing.

1 is a plan explanatory diagram of a preferred example of an embodiment of the present invention.
FIG. 2 is a cross-sectional view taken along the line II-II of FIG. 1. FIG.
3 is a bottom explanatory diagram of FIG. 1.
4 is a bottom explanatory diagram of the bearing body of FIG. 1.
5 is an enlarged cross-sectional explanatory diagram of a main part of FIG. 1.
6 is a plan explanatory view of a bearing base.
FIG. 7 is a cross-sectional view taken along the line VII-VII in FIG. 6. FIG.
8 is a plan explanatory view of a bearing body.
FIG. 9 is a cross-sectional explanatory diagram of the IX-IX line of FIG. 8. FIG.
FIG. 10 is a bottom explanatory diagram of FIG. 8. FIG.
It is sectional explanatory drawing of the combination of a bearing body and a bearing base.
It is a top explanatory drawing of another embodiment of a bearing body.
It is bottom explanatory drawing of another embodiment of a bearing base.
14 is a cross-sectional explanatory diagram of the XIV-XIV line in FIG. 13.
It is explanatory drawing of the cross section of the combination of a bearing body and a bearing base.
16 is a cross-sectional explanatory diagram of a hydrostatic gas bearing with an automatic alignment function.
17 is a bottom explanatory diagram of still another embodiment of a bearing base;
FIG. 18 is a cross-sectional explanatory diagram of the XVIII-XVIII line in FIG. 17. FIG.
It is sectional explanatory drawing of the combination of a bearing body and a bearing base.
20 is an explanatory cross-sectional view of a hydrostatic gas bearing with an automatic alignment function.
It is bottom explanatory drawing of another embodiment of a bearing base.
It is explanatory drawing of the XXII-XXII line of FIG.
It is explanatory drawing of the cross section of a fitting member.
It is sectional explanatory drawing of the bearing base which fit-fixed the fitting member.
It is explanatory drawing of the cross section of the combination of a bearing body and a bearing base.
Fig. 26 is an explanatory cross-sectional view of a hydrostatic gas bearing with an automatic alignment function.
It is sectional explanatory drawing of other embodiment of a fitting member.
It is sectional explanatory drawing of the bearing base which fit-fixed the fitting member.
It is sectional explanatory drawing of the combination of a bearing body and a bearing base.
30 is an explanatory cross-sectional view of a hydrostatic gas bearing with an automatic alignment function.
It is explanatory drawing of the cross section of a linear motion guide apparatus.

Next, the present invention will be described in more detail based on examples of preferred embodiments shown in the drawings. In addition, this invention is not limited to these examples at all.

1 to 5, the hydrostatic gas bearing 1 is preferably a thermoplastic synthetic resin such as polyacetal resin (POM), polyamide resin (PA), polyphenylene sulfide resin (PPS) or the like. A bearing base 2 formed of a reinforcing filler-containing thermoplastic synthetic resin containing 30 to 50 mass% of glass fiber, glass powder, carbon fiber or inorganic filler, or aluminum or aluminum alloy; A bearing body 3 made of synthetic resin, which is integrally bonded to the bearing base 2 with an adhesive and is preferably made of thermoplastic synthetic resin such as polyacetal resin, polyamide resin, polyphenylene sulfide resin, and the like; Equipped.

The bearing base 2 comprises, in particular, a base portion 4 as shown in FIGS. 6 and 7; A cylindrical projection 6 which is integrally protruded upward in the axial direction Y on the outer periphery of one of the planar circular surfaces 5 of the base portion 4; The planar circular surface 7 on the other side of the base portion 4; An air supply hole (10) having a circular opening (9) opened at one end (8) in the planar circular surface (5) of the base portion (4); An air supply passage 13 communicating with the air supply hole 10 at one end 11 and opening at the outer circumferential surface 12 of the base 4 at the other end.

A female screw 15 is formed on the inner circumferential surface 14 of the end of the air supply passage 13 opening to the outer circumferential surface 12 of the base portion 4, and a male screw of the air supply plug 16 is screwed into the female screw 15. , The air supply plug 16 is fixed to the outer circumferential surface 12 of the base portion 4 of the bearing base 2.

The bearing body 3, in particular, as shown in FIGS. 8 to 10, has a planar circular surface 17 facing one planar circular surface 5 of the base portion 4. The annular concave portion 18 formed, the annular concave groove 20 opened in the other planar circular surface 19, and the one end 21 communicate with the annular concave groove 20. At the same time, at the other end 22, a plurality of air blowing holes 25 opened to the annular bottom surface 24 of the annular recess 18 and an outer circumferential surface 23 adjacent to one planar circular surface 17. Has)

The annular concave groove 20 is defined by the cylindrical side surface 27 facing the annular bottom surface 26, and the annular concave groove 20 has a width W of at least 0.3 mm and a depth of at least 0.01 mm. (d), the air blowing hole 25 has a diameter (D) of at least 30 μm at one end 21, in this example, from one end 21 to the other end 22, and has an annular recess ( A magnetic stop is formed between 18) and the annular concave groove 20.

The annular recessed portion 18 is connected to an annular bottom surface 24 on which the other end 22 of the air blowing hole 25 opens and an outer edge of the annular bottom surface 24. The outer circumferential surface 28 and the inner circumferential surface 29 which are connected to the inner edge of the annular bottom surface 24 are defined, and the outer circumferential surface 28 and the inner circumferential surface 29 are each an annular bottom surface ( 24 is formed on the truncated conical surfaces 31 and 32 which gradually widen toward the end toward the opening 30 of the annular recess 18.

The bearing body 3 fits the outer circumferential surface 23 adjacent to one surface 17 to the inner surface of the cylindrical protrusion 6 of the bearing base 2, and is bonded by an adhesive at the fitting portion to form a bearing base ( 2) is integrated.

In the hydrostatic gas bearing 1, the annular concave groove 20 having a width W on the surface 19 of the bearing body 3 is at least 0.3 mm and a depth d is at least 0.01 mm, and one end 21. In the annular concave groove 20 and in the other end 22, a plurality of magnetic aperture shaped air ejecting holes having a diameter D of at least 30 μm opening to the annular bottom surface 24 of the annular concave portion 18. You may form (25) instantaneously by laser processing, for example.

In the above static pressure gas bearing 1, since the bearing body 3 is integrated with the bearing base 2 by an adhesive agent, the production thereof can be made easy and inexpensive. In addition, the air blowing hole 25 is very small in diameter D of at least 30 μm, and can suppress the generation of the self-excited vibration due to the large amount of air injection from the air blowing hole 25.

Next, an example of the manufacturing method of the hydrostatic gas bearing 1 shown in FIGS. 1 to 5 will be described. First, a bearing base made of reinforcing filler-containing synthetic resin or aluminum or aluminum alloy shown in FIGS. 6 and 7 is described. As the bearing body 3 made of synthetic resin shown in (2) and FIGS. 8 to 10, a bearing body 3a having no annular concave groove 20 and an air blowing hole 25 is prepared. As shown, the opening 30 of the annular recess 18 of the bearing body 3a is connected to the opening 9 of the air supply hole 10 of the bearing base 2, and at the same time, The outer circumferential surface 23 adjacent to one surface 17 is fitted to the inner surface of the cylindrical protrusion 6 of the bearing base 2, and then the fitting portion is bonded with an adhesive to form the bearing base 2 and the bearing body ( An assembly 33 incorporating 3a) is formed.

Thus, the laser beam is irradiated to the other surface 19 of the bearing body 3a in the integrated assembly 33 by a laser processing machine, and the width W is 0.3-1.0 mm, and the depth d is 0.01- The annular concave portion 18 penetrates the bearing body 3a from the annular bottom surface 26 to the annular concave groove 20 having a diameter of 0.05 mm and the annular bottom surface 26 defining the annular concave groove 20. A plurality of magnetic aperture-shaped air jet holes 25 having a diameter D of at least 30 μm, preferably 30 to 120 μm, which are opened to the annular bottom surface 24 are formed, thereby producing a constant pressure gas bearing 1. .

The processing laser to be used is selected from a carbon dioxide gas laser, a YAG laser, a UV laser or an excimer laser, and the like, and preferably a carbon dioxide gas laser is used.

The annular concave groove 20 having a width of 0.5 mm and a depth of 0.05 mm, centered on an arc of 30 mm diameter, uses a carbon dioxide laser with a laser output of 9.5 W, a scanning speed of 1000 mm / s, a number of overlap printing times, and machining time. It is possible to form and process the surface 19 of the bearing body 3a formed of polyphenylene sulfide resin in 2 seconds, and to the annular bottom surface 26 of the annular concave groove 20 from the annular bottom surface 26. A magnetic aperture-shaped air jet hole 25 having a diameter of 0.06 mm, which penetrates through the bearing body 3a and opens on the annular bottom surface 24 of the annular recess 18, has a circumference of 14 W with a laser output time of 15 seconds. Ten could be processed at ten equally spaced positions in the direction.

The bearing body 3 of the hydrostatic gas bearing 1 has one annular concave groove 20. In addition to the annular concave groove 20, the bearing body 3 is shown in FIG. It is formed in the other surface 19 of the bearing body 3, and it encloses the annular recessed groove 20 on the outer side of the annular recessed groove 20, and is concentric with the annular recessed groove 20. A plurality of radiations in which the large diameter annular recess 34 and one end 35 open into the annular recess 20 and the other end 36 opens in the large diameter annular recess 34. The concave groove 37 and the annular concave groove 20 are formed inside the annular concave groove 20, the concentric small diameter annular concave groove 38, and one end portion 39 are annular concave. A plurality of radially concave grooves 41 may be provided which open into the grooves 20 and the other end 40 opens into the small diameter annular concave grooves 38.

In the hydrostatic gas bearing 1 having the bearing body 3 shown in FIG. 12, the compressed air supplied to the annular concave groove 20 passes through the radial grooves 37 and 41 to the large diameter annular concave groove 34. And since it is supplied to the small diameter annular recessed groove 38, a supply area becomes large and it can perform the stable rise in the floating of an article, for example.

13 to 16 show another embodiment of the hydrostatic gas bearing 1, and in the center portion of the planar circular surface 7 of the other side of the bearing base 2, the planar circular surface is formed on the surface 7. A spherical hydraulic concave portion 43 having an opening 42 is formed, and the spherical hydraulic concave portion 43 extends from the bottom surface 44 and the opening surface 42 through the bottom surface 44 in a planar view. It has a truncated conical concave portion 46 defined by a truncated conical surface 45 that gradually increases.

The bearing base 2 including the spherical hydraulic recess 43 having the truncated conical recess 46 has the opening 9 of the air supply hole 10 similarly to the constant pressure gas bearing 1. The outer peripheral surface 23 adjacent to one side 17 of the bearing body 3 is communicated with the opening 30 of the annular recess 18 of the cylindrical base 6 of the bearing base 2. After fitting to the inner surface, the fitting portion is bonded with an adhesive to form an assembly 47 in which the bearing base 2 and the bearing body 3 are integrated.

Thus, the laser beam is irradiated to the other surface 19 of the bearing body 3 in the integrated assembly 47 by a laser processing machine, and the width W is 0.3-1.0 mm, and the depth d is 0.01- The annular concave portion 18 penetrates the bearing body 3 from the annular bottom surface 26 to the annular concave groove 20 having a diameter of 0.05 mm and the annular bottom surface 26 defining the annular concave groove 20. A plurality of magnetic aperture-shaped air jet holes 25 having a diameter D of at least 30 μm, preferably 30 to 120 μm, which are opened at the annular bottom surface 24 of the annular bottom surface 24 to form a constant pressure gas bearing 1. do.

In the hydrostatic gas bearing 1 thus formed, as illustrated in FIG. 16, the sphere 49 of the ball stud 48 slides on the conical surface 45 of the spherical hydraulic recess 43 of the bearing base 2. By placing in contact, an automatic alignment function is added.

17 to 20 show yet another embodiment of the hydrostatic gas bearing 1, in the center of the planar circular surface 7 of the other side of the bearing base 2, planar circular surface on the surface 7. A spherical hydraulic concave portion 43 having an opening portion 42 is formed, and the spherical hydraulic concave portion 43 extends from the bottom surface 44 to the opening portion 42 from the bottom surface 44 in a planar view. It has the concave spherical part 51 defined by the concave spherical surface 50 which spreads.

The bearing base 2 including the spherical hydraulic concave portion 43 having the concave spherical portion 51 has the opening 3 of the air supply hole 10, similar to the hydrostatic gas bearing 1, to the bearing body 3. The outer peripheral surface 23 adjacent to one side 17 of the bearing body 3 is communicated with the opening 30 of the annular recess 18 of the cylindrical base 6 of the bearing base 2. After fitting to the inner surface, the fitting portion is bonded with an adhesive to form an assembly 52 in which the bearing base 2 and the bearing body 3 are integrated.

Thus, the laser beam is irradiated to the other surface 19 of the bearing body 3 in the integrated assembly 52 with a laser processing machine, and the width W is 0.3-1.0 mm, and the depth d is 0.01-. The annular concave portion 18 penetrates the bearing body 3 from the annular bottom surface 26 to the annular concave groove 20 having a diameter of 0.05 mm and the annular bottom surface 26 defining the annular concave groove 20. A plurality of magnetic aperture-shaped air jet holes 25 having a diameter D of at least 30 μm, preferably 30 to 120 μm, which are opened at the annular bottom surface 24 of the annular bottom surface 24 to form a constant pressure gas bearing 1. do.

In the hydrostatic gas bearing 1 thus formed, as shown in FIG. 20, the sphere 49 of the ball stud 48 slides on the concave spherical surface 50 of the spherical hydraulic concave portion 43 of the bearing base 2. By placing in contact, an automatic alignment function is added.

21 to 26 show another embodiment of the hydrostatic gas bearing 1 to which the automatic alignment function is added. In the center part of the planar circular surface 7 of the other side of the bearing base 2, the cylindrical recessed part 55 which has the circular bottom surface 54 opened by the surface 7 is formed, and a cylinder As shown in FIG. 23, the cylindrical recess 55 includes a cylinder 56, a hole 59 opening from one end 57 on one surface 58 of the cylinder 56, and a hole 59. Conical face 62, which is connected to the other end 60 of the opening 60 and gradually widens from the other end 60 toward the other side 61 of the cylindrical body 56 toward the end, and opens at the other side 61. The fitting member 64 having the recessed portion 63 having the recessed side faces the one side 58 toward the bottom surface 54 of the cylindrical recessed portion 55, and the other side 61 is the bearing base. It is located on the same surface as the other surface 7 of (2), and is fitted and fixed. The concrete hydraulic recess 43 has such a truncated conical surface 62.

The bearing base 2 in which the fitting member 64 is fitted is fixed to the opening 9 of the air supply hole 10 in the same way as the hydrostatic gas bearing 1 of the annular recess 18 of the bearing body 3. While communicating with the opening 30, the outer peripheral surface 23 adjacent to one surface 17 of the bearing body 3 is fitted to the inner surface of the cylindrical protrusion 6 of the bearing base 2, and then fitted therein. The fitting portion is bonded with an adhesive to form an assembly 65 in which the bearing base 2 and the bearing body 3 are integrated.

Thus, the laser beam is irradiated to the other surface 19 of the bearing body 3 in the integrated assembly 65 by the laser processing machine, and the width W is 0.3-1.0 mm, and the depth d is 0.01- The annular concave portion 18 penetrates the bearing body 3 from the annular bottom surface 26 to the annular concave groove 20 having a diameter of 0.05 mm and the annular bottom surface 26 defining the annular concave groove 20. A plurality of magnetic aperture-shaped air jet holes 25 having a diameter D of at least 30 μm, preferably 30 to 120 μm, which are opened at the annular bottom surface 24 of the annular bottom surface 24, to produce a constant pressure gas bearing 1. .

In the hydrostatic gas bearing 1 formed as described above, as shown in FIG. 26, the conical face of the concave portion 63 of the fitting member 64 fixed to the cylindrical concave portion 55 of the bearing base 2 is fixed. The sphere 49 of the ball stud 48 is disposed in sliding contact with the 62, so that an automatic alignment function is added.

27 to 30 show another embodiment of the hydrostatic gas bearing 1 to which the automatic alignment function is added. As shown in FIG. 22, at the center of the planar circular surface 7 on the other side of the bearing base 2, a cylindrical recess having a circular bottom surface 54 opening in the surface 7 ( 55 is formed, and the cylindrical concave portion 55 has a cylindrical body 56 and a hole opening at one end 58 of the cylindrical body 56 at one end 57 as shown in FIG. 59 and a concave spherical surface which is connected to the other end 60 of the circular hole 59 and opens from the other end 61 toward the other surface 61 of the cylindrical body 56 at the other end 60 ( The fitting member 64 with the recess 63 having the recess 66 faces one side 58 toward the bottom surface 54 of the cylindrical recess 55, and the other side 61 bearings. It is located on the same surface as the other surface 7 of the base 2, and is fitted and fixed. The concrete hydraulic recess 43 has such a concave spherical surface 66.

The bearing base 2 to which the fitting member 64 is fitted is fixed to the opening 9 of the air supply hole 10 in the same way as the hydrostatic gas bearing 1 of the annular recess 18 of the bearing body 3. While communicating with the opening 30, the outer peripheral surface 23 adjacent to one surface 17 of the bearing body 3 is fitted to the inner surface of the cylindrical protrusion 6 of the bearing base 2, and then fitted therein. The fitting portion is bonded with an adhesive to form an assembly 67 in which the bearing base 2 and the bearing body 3 are integrated.

Thus, the laser beam is irradiated to the other surface 19 of the bearing body 3 in the integrated assembly 67 by the laser processing machine, and the width W is 0.3-1.0 mm, and the depth d is 0.01-. The annular concave portion 18 penetrates the bearing body 3 from the annular bottom surface 26 to the annular concave groove 20 having a diameter of 0.05 mm and the annular bottom surface 26 defining the annular concave groove 20. A plurality of magnetic aperture-shaped air jet holes 25 having a diameter D of at least 30 μm, preferably 30 to 120 μm, which are opened at the annular bottom surface 24 of the annular bottom surface 24 to form a constant pressure gas bearing 1. do.

The concave spherical surface of the concave portion 63 of the fitting member 64 fitted into the cylindrical concave portion 55 of the bearing base 2 as shown in FIG. 30 in the hydrostatic gas bearing 1 thus formed. The sphere 49 of the ball stud 48 is placed in sliding contact with the 66 to add an automatic alignment function.

A polyacetal resin having excellent sliding characteristics, for example, having a sliding fitting member 64 fitted to a cylindrical recess 55 formed in the center of the other planar circular surface 7 of the bearing base 2 on the other side. Conical surface 62 or concave of concave portion 63 of fitting member 64 by being formed of thermoplastic synthetic resin having self-lubricating properties such as polyamide resin, polyester resin, copper or copper alloy, or the like. The sliding contact between the spherical surface 66 and the sphere 49 of the ball stud 48 can be performed smoothly.

FIG. 31 shows a linear motion guide device 68 using the hydrostatic gas bearing 1 shown in FIG. 26, wherein the linear motion guide device 68 has a guide member having an upper guide surface 69 and both guide surfaces 70 and 70. FIG. 71 and an upper plate 72 facing the upper guide surface 69 disposed over the outer side of the guide member 71 and a pair of side plates 73 and 73 facing the two guide surfaces 70 and 70. The sphere 49 is directed inwardly on the inner surface 76 of each of the cross-section “c” shaped movable tables 74 and the lower surface 75 and the side plates 73 and 73 of the upper plate 72 of the movable table 74. The conical face 62 of the fitting member 64 between the ball stud 48 and the upper guide surface 69 of the ball stud 48 and the guide member 71 and the both guide surfaces 70 and 70. While making sliding contact with the sphere 49 of the ball stud 48, the other surface 19 of the bearing body 3 is moved to the upper guide surface 69 and both guide surfaces 70 and 70 of the guide member 71. Placed face to face Is formed in the static pressure gas bearing (1).

According to the linear motion guide device 68, compressed air is injected from the plurality of air blowing holes 25 of the bearing body 3 to the upper guide surface 69 and the both guide surfaces 70 and 70 of the guide member 71. The upper surface of the movable table 74 by an air lubrication film formed between the other surface 19 of the bearing body 3, the upper guide surface 69 of the guide member 71, and both guide surfaces 70 and 70. The guide surface 69 and both guide surfaces 70 and 70 can be held in a non-contact state. When the bearing clearance between the bearing body 3, the upper guide surface 69, and the both guide surfaces 70 and 70 is non-uniform, a pressure difference occurs in each of the bearing clearances, and the pressure difference makes the bearing clearance uniform. Direction, the positive pressure gas bearing 1 is automatically aligned, and the parallel state with respect to the upper guide surface 69 and both guide surfaces 70 and 70 is maintained. For this reason, the precision of components, such as the parallelism and the squareness, of the guide member 71 and the movable table 74 can be made into comparatively rough precision, and the linear motion guide apparatus 68 is added to the low cost of the hydrostatic gas bearing 1 itself. The production can be facilitated and the cost can be reduced.

In the linear motion guide 68, the static gas bearing 1 as shown in FIG. 26 was used as the static gas bearing 1 with an automatic alignment function, but instead of FIG. 16, FIG. 20 and FIG. The hydrostatic gas bearing 1 shown may also be used.

As described above, since the bearing body and the bearing base are fitted with the outer circumferential surface adjacent to one surface of the bearing body to the inner surface of the cylindrical protrusion of the bearing base, the fitting part is bonded and bonded with an adhesive, so that the bearing body and the bearing body are integrated. The joint surface of the bearing base is tightly sealed, and one surface of the bearing body has an annular concave groove having a width W of 0.3 to 1.0 mm and a depth d of 0.01 to 0.05 mm, and an annular concave groove. The bottom surface is formed with a plurality of magnetic aperture-shaped air jet holes having a diameter D of at least 30 μm passing through the bearing body from the annular bottom surface and opening at the annular bottom surface of the annular recess. Since the ejection hole can be formed without machining, it is not only possible to provide an inexpensive hydrostatic gas bearing, but also to facilitate the manufacture and non-compression using the hydrostatic gas bearing. It is possible to provide a linear motion guide device that can be made lower.

1 static gas bearing
2 Bearing base
3 bearing body
4 base part
6 Cylindrical protrusion
13 air supply passage
18 annular recess
20 annular recesses
23 outer circumference
25 air blowers

Claims (10)

A base portion, a cylindrical protrusion protruding from the outer periphery of one side of the base portion, and an air supply passage opening at one end of the base portion at the other end thereof and opening at the outer peripheral surface of the base portion at the other end thereof; One bearing base; The annular recess formed in one surface facing one side of the base portion, the annular recess opened in the other surface, and the annular recess in one end thereof, and at the other end, the annular recess in the annular recess. A bearing body made of a synthetic resin having a plurality of air blowing holes as an open magnetic aperture, the bearing body fitting an outer circumferential surface adjacent to one surface to an inner surface of a cylindrical protrusion of the base portion; It is bonded at the fitting part and integrated in the bearing base. The annular recess has a width of at least 0.3 mm and a depth of at least 0.01 mm, and the air ejection hole has a diameter of at least 30 μm at one end thereof, and A hydrostatic gas bearing, characterized in that a magnetic aperture is formed between the annular recesses. The method according to claim 1,
The annular recess has a width of 0.3 ~ 1.0mm or 0.3 ~ 0.7mm and a depth of 0.01 ~ 0.05mm or 0.01 ~ 0.03mm, and the air jet hole has a diameter of 30 ~ 120μm at one end. . The method according to claim 1 or 2,
Each of the annular recesses and the air jetting holes is formed by laser processing. 4. The method according to any one of claims 1 to 3,
A hydrostatic gas bearing in which a spherical hydraulic depression is formed on the other side of the bearing base. The method of claim 4,
A concrete hydraulic concavity is a hydrostatic gas bearing having a truncated conical concave that opens on the other side of the bearing base. The method of claim 4,
A concrete hydraulic concave portion is a hydrostatic gas bearing having a concave spherical portion that opens on the other side of the bearing base. The method of claim 4,
On the other side of the bearing base, a cylindrical recess is formed, which is opened from the other side thereof, a fitting member is fitted and fixed to the cylindrical recess, and the concrete hydraulic recess is formed on the other side of the bearing base. A hydrostatic gas bearing having a conical surface formed on the fitting member while opening at one face of the fitting member on the face side. The method of claim 4,
On the other side of the bearing base, a cylindrical recess is formed, which is opened from the other side thereof, a fitting member is fitted and fixed to the cylindrical recess, and the concrete hydraulic recess is formed on the other side of the bearing base. A hydrostatic gas bearing having a concave spherical surface formed in the fitting member while being opened at one surface of the fitting member on the surface side. The method according to any one of claims 1 to 8,
In addition to the annular concave groove, the bearing body is formed on the other side and at the outside of the annular concave groove, a large diameter annular concave groove surrounding the annular concave groove, and one end thereof is the annular concave groove. A plurality of first radial concave grooves opened at the same time and the other end is opened in a large diameter annular recess, a small diameter annular recess formed inside the annular recess, and one end is an annular recess. A hydrostatic gas bearing having a plurality of second radial recesses which open at the same time as the other end and open in a small diameter annular recess. On the outside of the guide member having an upper guide surface and both side guide surfaces, a movable table having a cross-section " c " shape having a top plate facing the top guide surface and a pair of side plates facing both guide surfaces is disposed, and the top plate of the movable table. The inner surface of each of the lower surface and the side plate of the ball studs are installed with the sphere facing inward, respectively, between the upper guide surface and both guide surfaces of the ball stud and the guide member, the positive pressure gas bearing according to any one of claims 1 to 9. A linear motion guide device, wherein the concrete hydraulic recess is in sliding contact with the sphere of the ball stud, and the bearing body is disposed to face the upper guide surface and both guide surfaces of the guide member.

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