JP3911064B2 - Air slide device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an air slide device used for an apparatus that requires high positioning accuracy, straightness, etc., such as a liquid crystal display, a plasma display apparatus, and a semiconductor manufacturing apparatus.
[0002]
[Prior art]
As an air slide device, a configuration is known in which the upper, lower, left, and right surfaces of a square columnar guide member are used as guide surfaces, and the slide member is slidably and non-contactedly supported by two pairs of upper, lower, left, and right air bearings (Japanese Patent Laid-Open No. Hei. No. 3-37412, Japanese Utility Model Publication No. 2-68676). By setting the bearing rigidity of the pair of upper and lower air bearings equal to the bearing rigidity of the pair of left and right air bearings, a good straightness is obtained by balancing the upper and lower and left and right sides.
[0003]
[Problems to be solved by the invention]
Since the conventional air slide device uses the four sides of the square columnar guide member as the guide surface, the parallelism of the upper and lower surfaces of the guide member, the parallelism of the left and right surfaces, and the direct connection between the upper and lower surfaces and the left and right surfaces. It is necessary to ensure the angle with high accuracy over the entire length, and it has been difficult to increase the length of the guide member for manufacturing and cost reasons. In addition, when the guide member is bent in the vertical direction due to thermal deformation and the guide member is supported at both ends, the vertical deflection due to the load greatly affects the vertical straightness, so that the stroke cannot be made very large. There was a problem.
[0004]
The main object of the present invention is to solve the problem of manufacturing the guide member and the problem of vertical straightness in the conventional apparatus, and to provide a low-cost, long stroke and highly accurate air slide apparatus.
[0005]
[Means for Solving the Problems]
The air slide device of the present invention includes a first guide member having a pair of left and right guide surfaces parallel to each other, a second guide member having a guide surface facing the lower surface of the first guide member, and a pair of left and right in the left-right direction. The air bearing is supported in a non-contact manner on the guide surface of the first guide member. In the vertical direction, there is sufficient clearance between the upper surface and the lower surface of the first guide member (even under conditions such as load load, deflection of the first guide member). A slide member that is supported in a non-contact manner on the guide surface of the second guide member, and a linear motor that slide-drives the slide member. is there. The linear motor includes a linear motor magnet fixed on a base and a linear motor coil mounted on a slide member, and a second guide member made of a magnetic material is used as a yoke, and the second guide member and the linear motor. A linear motor coil is arranged in a magnetic circuit formed between the magnets.
[0006]
As a configuration for supporting the slide member in a non-contact manner on the guide surface of the second guide member, the bearing force of the air bearing, the magnetic attraction force of the suction magnet, and its own weight (the own weight of the slide member. The load applied to the slide member) In other words, it is possible to adopt a configuration in which it is supported in a non-contact manner according to the balance. Any other means of balance between the bearing force of the air bearing and its own weight, the balance between the magnetic repulsion force and its own weight of the repulsion magnet, and the balance between the bearing force of the air bearing and the magnetic repulsion force of the rebound magnet and its own weight It is also possible to adopt a configuration that supports non-contact.
[0007]
A pair of left and right bearing surfaces facing the guide surface of the first guide member via a bearing gap, a bearing surface facing the guide surface of the second guide member via a bearing gap, and supplying compressed air to these bearing gaps The nozzle for this can be provided in a slide member. Further, the suction magnet can be provided on the bearing surface of the slide member facing the guide surface of the second guide member. Furthermore, it can be set as the structure which supported the 2nd guide member on the base over the full length.
[0008]
In the above air slide device, the left and right independent magnetic circuits are formed by the second guide member and the linear motor magnet fixed to the left and right upper surfaces of the base, and the linear motor coil is arranged in each magnetic circuit. it can.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to FIGS. 1 is a cross-sectional view (cross-sectional view taken along line AA in FIG. 3) of the air slide device of this embodiment, FIG. 2 is a plan view, and FIG. 3 is a side view.
[0010]
The air slide device of this embodiment is of a type in which the slide member 3 is supported in a non-contact manner on the guide surfaces of the first guide member 1 and the second guide member 2 and is slid and driven by a linear motor 4.
[0011]
The first guide member 1 is a quadrangular columnar member having a pair of left and right guide surfaces 1a and 1b parallel to each other, and both ends thereof are supported and fixed to the base 6 by a pair of guide columns 5 in a bilateral manner. The guide surfaces 1a and 1b of the first guide member 1 are subjected to precision processing for ensuring the required parallelism between them, but such precision processing is applied to the upper surface 1c and the lower surface 1d. It has not been.
[0012]
The second guide member 2 is a flat block member whose upper surface is a guide surface 2a, and is supported and fixed to the base 6 over the entire length by the guide support 7 at the center in the width direction (entire installation type). The guide surface 2a of the second guide member 2 is precision machined to ensure the required accuracy. The second guide member 2 is made of a magnetic material and also serves as a yoke for the linear motor 4 described later.
[0013]
The slide member 3 has a rectangular cylindrical shape mainly composed of an upper plate 3a, a pair of side plates 3b and 3c, and a lower plate 3d, and is slidably inserted into the first guide member 1.
[0014]
1B, the inner surface of the side plate 3b and the inner surface of the side plate 3c are opposed to the guide surfaces 1a and 1b of the first guide member 1 via predetermined bearing gaps S1 and S2, respectively. Bearing surfaces 3b1, 3c1 are provided. Between the inner surface 3a1 of the upper plate 3a and the upper surface 1c of the first guide member 1, and between the inner surface 3d1 of the lower plate 3d and the lower surface 1d of the first guide member 1, sufficient gaps L1, L2 (load Even if there is a load, the first guide member 1 is bent, etc., a gap having a size that does not contact the upper surface 1c and the lower surface 1d is provided. Further, a plurality of nozzles 3b2, 3C2 are opened in the bearing surfaces 3b1, 3c1, respectively, and a pair of left and right are supplied by supplying compressed air P to the bearing gaps S1, S2 from the outside via the nozzles 3b2, 3C2. The air bearing is configured.
[0015]
The bearing surfaces 3b1, 3c1 are supported in a non-contact manner relative to the guide surfaces 1a, 1b by the pressure distribution of the compressed air P flowing into the bearing gaps S1, S2 via the nozzles 3b2, 3C2. Since the gaps L1 and L2 are provided, the upper surface 1c and the lower surface 1d of the first guide member 1 are not involved in the support guide of the slide member 3.
[0016]
As shown in an enlarged view in FIG. 1C, the outer surface of the lower plate 3d of the slide member 3 is provided with a bearing surface 3d1 that opposes the guide surface 2a of the second guide member 2 with a predetermined bearing gap S3. It is done. A plurality of nozzles 3d2 are opened in the bearing surface 3d1, and an air bearing is configured by supplying compressed air to the bearing gap S3 from the outside via the nozzle 3d2. Further, a suction magnet (permanent magnet) 3d3 is embedded in the bearing surface 3d1 so as to face the guide surface 2a with a predetermined gap G interposed therebetween.
[0017]
Due to the balance between the pressure distribution of the compressed air P flowing into the bearing gap S3 through the nozzle 3d2, the magnetic attraction force with respect to the guide surface 2a of the suction magnet 3d3 and the weight of the slide member 3 (including the load applied). The bearing surface 3d1 is supported in a non-contact manner with respect to the guide surface 2a. The balance includes parameters such as the size of the bearing gap S3, the orifice diameter, the number, the arrangement position of the nozzle 3d2, the pressure and flow rate of the compressed air to be supplied, the size of the gap G, and the attractive force of the suction magnet 3d3. Optimum adjustment can be performed by appropriately setting according to use conditions.
[0018]
The linear motor 4 includes a linear guide disposed in a magnetic circuit formed between the second guide member 2 as a yoke made of a magnetic material, a linear motor magnet 4a, and the second guide member 2 and the linear motor magnet 4a. The motor coil 4c is configured as a main element. In this embodiment, the linear motor magnet 4 a is composed of a magnetic material 4 a 1 and a plurality of permanent magnets 4 a 2, and is fixed to the left and right upper surfaces of the base 6 with the guide column 7 interposed therebetween. The linear motor coils 4c are arranged in the left and right independent magnetic circuits formed between the second guide member 2 and the left and right linear motor magnets 4a, and the coil mounting plate 4c1 is attached to the lower plate 3d1 of the slide member 3. It is mounted via.
[0019]
When an electric current is passed through the linear motor coil 4c placed in the magnetic circuit as described above, a propulsive force in the sliding direction is generated, and thereby the slide member 3 is driven to slide.
[0020]
When compressed air P is supplied to the nozzle 3b2 of the side plate 3b, the nozzle 3c2 of the side plate 3c, and the nozzle 3d2 of the lower plate 3d, and current is passed through the linear motor coil 4c, the slide member 3 moves in the left-right direction (horizontal direction). A pair of left and right air bearings (nozzle 3b2 and nozzle 3c2) are supported in a non-contact manner on the left and right guide surfaces 1a and 1b of the first guide member 1, and the upper surface of the first guide member 1 in the vertical direction (vertical direction). 1c and the lower surface 1d with sufficient clearances L1 and L2, and the balance between the bearing force of the air bearing (nozzle 3d2), the magnetic attraction force of the suction magnet 3d3 and its own weight, with respect to the guide surface 2a of the second guide member 2 In a non-contact supported state, the linear motor 4 slides and slides along the first guide member 1 and the second guide member 2.
[0021]
The non-contact support of the slide member 3 with respect to the guide surface 2a of the second guide member 2 does not use a balance between the bearing force of the air bearing (nozzle 3d2) and its own weight (in this case, a magnet for suction or repulsion). ), Balance between the magnetic repulsion force of the repulsion magnet and its own weight (various known structures can be adopted as the repulsion magnet), the bearing force of the air bearing (nozzle 3d2), and the magnetic repulsion of the repulsion magnet. You may carry out by balance of power and dead weight. The air bearing nozzles 3b2, 3c2, 3d2 may be supplied with compressed air P from the outside via individual air supply ports, or all the nozzles 3b2, 3c2, 3d2 are connected to the slide member 3. An air passage may be formed, and the compressed air P may be supplied from the outside through a common air supply port. Alternatively, an air bearing nozzle may be provided in the first guide member 1 and the second guide member 2.
[0022]
【The invention's effect】
The present invention has the following effects.
[0023]
(1) Since the slide member is configured to slide and guide on the three surfaces of the pair of left and right guide surfaces of the first guide member and the guide surface of the second guide member, precision processing of the upper surface and the lower surface of the first guide member becomes unnecessary. The long first guide member can be manufactured at low cost. In addition, since the upper and lower surfaces of the first guide member are not used as guide surfaces, vertical straightness is not affected even if the first guide member bends in the vertical direction. Furthermore, the installation location of the air bearing can be reduced from the conventional 4 locations to 3 locations. Therefore, it is possible to provide a long stroke and highly accurate air slide device at low cost. In addition, the linear motor magnet of the linear motor that slides the slide member is fixed on the base, and the linear motor coil is mounted on the slide member. Compared to the moving magnet type (configuration in which the linear motor magnet is fixed to the movable side) Since the weight on the slide member side is reduced, the acceleration characteristics of the linear motor are improved. In addition, the impedance characteristics are improved as compared with the configuration in which the linear motor coil is disposed on the base over the entire stroke. Therefore, it is possible to provide a long stroke and highly accurate air slide device. In addition, since the second guide member is formed of a magnetic material and is also used as the yoke of the linear motor, the number of parts and the number of manufacturing steps can be reduced, and the cost can be reduced.
[0024]
(2) By supporting the second guide member on the base over the entire length (entire installation type), the vertical deflection of the second guide member can be prevented, and good vertical straightness can be obtained.
[0027]
(5) By adopting a configuration in which the linear motor coils are arranged in the left and right independent magnetic circuits, the structure of the second guide member as the yoke and the linear motor coil can be simplified.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view (cross-section AA in FIG. 3) of an air slide device according to an embodiment.
FIG. 2 is a plan view of the air slide device according to the embodiment.
FIG. 3 is a side view of the air slide device according to the embodiment.
1 first guide member 1a guide surface 1b guide surface 1c upper surface 1d lower surface 2 second guide member 2a guide surface 3 slide member 3b1 bearing surface 3b2 nozzle 3c1 bearing surface 3c2 nozzle 3d1 bearing surface 3d2 nozzle 3d3 suction magnet 4 linear motor 4a linear Motor magnet 4c Linear motor coil 6 Base

Claims (6)

A first guide member having a pair of left and right guide surfaces parallel to each other;
A second guide member having a guide surface facing the lower surface of the first guide member;
In the left-right direction, a pair of left and right air bearings are supported in a non-contact manner on the guide surface of the first guide member, and in the up-down direction, a sufficient gap is maintained between the upper and lower surfaces of the first guide member, A slide member supported in a non-contact manner on the surface ;
A linear motor that slides the slide member,
The linear motor includes a linear motor magnet fixed on a base and a linear motor coil mounted on a slide member, and a second guide member made of a magnetic material is used as a yoke, and the second guide member and the linear motor. An air slide device in which a linear motor coil is arranged in a magnetic circuit formed between magnets .   The air slide device according to claim 1, wherein the slide member is supported in a non-contact manner on the guide surface of the second guide member by a balance between the bearing force of the air bearing, the magnetic attractive force of the suction magnet, and its own weight.   A pair of left and right bearing surfaces that oppose the guide surface of the first guide member via a bearing gap, a bearing surface that opposes the guide surface of the second guide member via a bearing gap, and supply compressed air to these bearing gaps The air slide device according to claim 1, wherein a nozzle for providing the nozzle is provided on the slide member.   The air slide device according to claim 3, wherein the suction magnet is provided on a bearing surface of the slide member facing the guide surface of the second guide member.   The air slide device according to claim 1, 2, 3, or 4, wherein the second guide member is supported on the base over its entire length. Left and right independent magnetic circuit between the linear motor magnet fixed to the second guide member and the base of the left and right upper surface is formed, air slide device according to claim 1, wherein the magnetic circuits each linear motor coils in was arranged .

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