JP2000262036A - Linear motor drive air slide - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a linear motor drive air slide, which ensures rigidity in the sliding direction of an air slide and also reduces the influence that the thermal expansion transformation of the coil of the linear motor exerts on the accuracy of a bearing. SOLUTION: This linear motor drive air slide is constituted, such that respective pieces of guide bars 12 and 12 are provided in parallel a specified interval apart on a base 11, and a slider 14 constituting an air slide unit 10 is set to each guide bar 12, and also the two sliders 14 are coupled with each other through a stage 16, and on the base 11, a linear motor 20 is provided between guide bars 12 on both sides, and the coil 23 of the linear motor 20 is coupled with each slider 14, and the distance between the coil 23 which is a thrust generation part and the gas bearing of a slider 14 is set small.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air slide driven by a linear motor used in a semiconductor manufacturing apparatus such as a bonding machine or an inspection apparatus.

[0002]

2. Description of the Related Art As shown in FIGS. 5 (a) and 5 (b), a linear motor driven air slide of this type which has been conventionally used is a combination of an air slide 1 and a voice coil type DC linear motor 2. The air slide 1 has a slider 5 slidably mounted on a guide bar 4 having a rectangular cross section fixed to a base 3 via a gas bearing.

The linear motor 2 is provided with an upward U-shaped yoke 6 along the guide bar 4 at a position lower than the upper surface of the base 3, and the yoke 6 is formed on opposite inner surfaces on both side surfaces thereof. Permanent magnets 7, 7 having a length substantially corresponding to the entire length of the yoke 6 are attached.

The yoke 6 has a center yoke 6 ', and a coil 8 as a movable portion is slidably fitted to the center yoke 6'. The support member 9 of the coil 8 is fixed to the lower surface of the air slide 1.

[0005]

An air slide driven by a linear motor used in a bonding machine or the like requires a linear reciprocating motion at high speed. To meet this demand, it is necessary to increase the rigidity of the air slide in the sliding direction in order to improve the response characteristics to the control system.

[0006] However, the conventional air slide 1
And the linear motor 2 as a thrust generating section are arranged vertically, the distance (offset) between the bearing section and the thrust generating section becomes large, and therefore the moment load during acceleration increases. High rigidity in the sliding direction could not be obtained.

On the other hand, if the distance between the bearing portion and the thrust generating portion is large as described above, the linear motor 2 generates heat and the coil 8
Although there is an advantage that even if the portion of the air slide 1 is inflated and deformed, the influence of the inflated deformation on the bearing accuracy of the air slide 1 is small,
Conversely, if the distance is small, the accuracy of the bearing is reduced due to the thermal expansion of the coil 8 and the sliding resistance of the air slide 1 is increased.

Accordingly, an object of the present invention is to provide a linear motor driven air slide in which the rigidity of the air slide in the sliding direction is secured and the influence of thermal expansion deformation of the linear motor coil on bearing accuracy is reduced. And

[0009]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a linear motor that drives a slider by fitting a slider to a guide bar via a gas bearing to form an air slide. In a linear motor driven air slide having a base for supporting them, two guide bars are installed in parallel on the base at a predetermined interval, and the slider is fitted to each guide bar, and The sliders are connected by a stage, the linear motor is provided between the guide bars on both sides of the base, and the movable portion of the linear motor is connected to each slider.

The permanent magnet of the linear motor is installed on the base over the moving range of the slider, and the movable part of the linear motor is constituted by a flat coil arranged on the permanent magnet with a predetermined gap. A configuration in which the yoke of the linear motor is formed in a size to cover the installation range of the permanent magnet, and the yoke is arranged on the movable portion with a predetermined gap, and both ends are fixed to the base. Can be taken.

The above-mentioned guide bar is formed by a round bar having a circular cross section, and one end of the above-mentioned stage is attached to one of the sliders so as to be movable in a direction perpendicular to the moving direction of the slider. A configuration can be adopted in which one end of the stage is attached to one of the sliders via a linear motion guide.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The linear motor-driven air slide of the embodiment shown in FIGS. 1 to 4 has round bar-shaped guide bars 12, 1 on the left and right sides on a base 11, respectively.
2 is fixed via fixing stands 13 and 13. A slider 14 is fitted to each guide bar 12, and the slider 14
A nozzle (not shown) connected to the air hose 15 is provided on the inner peripheral surface of the cylinder, and a gas bearing is formed by ejecting static pressure air from the nozzle. The air slide 10 is constituted by the guide bar 12 and the slider 14 fitted to the guide bar 12 via a gas bearing.

A stage 16 is laid over the upper surfaces of the sliders 14 on both sides, one end of which is fixed to one slider 14 by bolts 17 and the other end of which is connected to the other slider 14 by a cross roller guide 18. The slider 14 is slidably supported in a direction perpendicular to the moving direction of the slider 14 via a linear guide such as 18. As shown in FIG. 3, one guide piece 18a of each cross roller guide 18 is attached to the stage 16 by bolts 27a, and the other guide piece 18b is attached to the slider 14 by bolts 27b.
Attached to

Further, on the base 11 between the sliders 14 on both sides, a required number of permanent magnets 19 as fixing portions of the linear motor 20 are installed. Each of the permanent magnets 19 has a strip shape, both ends of which are oriented in the direction of the guide bars 12, 12 and are arranged at regular intervals in the length direction of the guide bars 12, 12. The polarity of each of these permanent magnets 19 is
As shown in FIG. 4, the polarities are determined so that the polarities become opposite in order.

A flat coil 23 having a three-phase coil 22 (see FIG. 4) mounted on a flat coil guard 21 (see FIGS. 2 and 4) with a small gap above the permanent magnet 19 described above. Is arranged. The coil 23 forms a movable portion of the linear motor 20, and both ends of the coil guard 21 are fixed to the lower surfaces of the sliders 14 on both sides by bolts 26.

Between the sliders 14 on both sides, a yoke 24 large enough to cover all the permanent magnets 19 is arranged on the coil 22 with a small gap therebetween. The legs 25, 25 of the yoke 24 provided at both ends in the length direction are fixed to the base 11.

The air slide driven by the linear motor according to the embodiment is as described above. By supplying a three-phase alternating current to the coil 23, the linear motor 20 acts as a synchronous linear motor, and a thrust is generated in the coil 23. (See FIG. 4). When a thrust is generated in the coil 23, the sliders 14, 14 on both sides connected to the coil 23 slide on the guide bars 12, 12 together with the stage 16 via a gas bearing.

According to the above configuration, since the linear motor 20 is provided between the two guide bars 12, 12, the yoke 24 constituting a part of the magnetic circuit of the linear motor 20 is provided.
Can be provided between the guide bars 12, 12.
In combination with the fact that the coil 23 is flat, the distance between the coil 23 that is the thrust generating unit and the gas bearing portion of the air slide 10 is reduced. As a result, the moment load during acceleration is reduced, and the rigidity of the air slide 10 in the sliding direction is ensured.

When the coil 23 thermally expands, the coil guard 21 is deformed as shown by an arrow a in FIG. 2, and the sliders 14 are further deformed as shown by an arrow b. The stage 16 suspended over the sliders 14, 14 has one end fixed by bolts 17 and the other end slidable by cross roller guides 18, 18. Roller guide 18,
Deform to the 18 side (see arrow c). At the cross roller guides 18 and 18, as shown by arrows d and d in FIG. 1, the guide piece 18 a on the stage 16 and the guide piece 18 b on the slider 14 slide in opposite directions to cause the heat. Absorbs deformation due to expansion. Therefore, even if there is deformation due to thermal expansion, free sliding of the sliders 14 and 14 is not hindered.

[0020]

As described above, according to the present invention, since the distance between the thrust generating portion of the linear motor and the gas bearing portion of the air slide is reduced, the moment load during acceleration is reduced.
The rigidity of the air slide in the sliding direction is ensured.

The guide bar of the slider constituting the air slide is formed of a round bar, and one end of the stage is slidably mounted on one of the sliders, thereby absorbing the thermal expansion of the coil of the linear motor. , The slider can be moved smoothly.

[Brief description of the drawings]

FIG. 1 is a partially cutaway plan view of an embodiment.

FIG. 2 is a sectional view taken along line II-II of FIG.

FIG. 3 is a sectional view taken along line III-III in FIG. 1;

FIG. 4 is a schematic view of a linear motor part according to the first embodiment;

5A is a cross-sectional view of a conventional example. FIG. 5B is a cross-sectional view taken along line bb in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Air slide 2 Linear motor 3 Base 4 Guide bar 5 Slider 6 Yoke 6 'Center yoke 7 Permanent magnet 8 Coil 9 Support member 10 Air slide 11 Base 12 Guide bar 13 Fixing stand 14 Slider 15 Air hose 16 Stage 17 Bolt 18 Cross roller guide 18a, 18b Guide piece 19 Permanent magnet 20 Linear motor 21 Coil guard 22 Three-phase coil 23 Coil 24 Yoke 25 Leg 26 Bolt 27a, 27b Bolt

Continuation of the front page F term (reference) 3F021 AA01 AA03 BA02 CA06 CA11 DA08 5H641 BB06 BB18 GG03 GG07 HH02 JA06 JA09

Claims (4)

[Claims] 1. A linear motor drive air slide comprising a linear motor for driving the slider and a base for supporting the linear motor, the slider being fitted to a guide bar via a gas bearing to form a slider. Two guide bars are installed in parallel on the base at a predetermined interval, the sliders are fitted to the guide bars, and the sliders are connected by a stage, and the linear motor is connected to the base. A linear motor-driven air slide, wherein the movable portion of the linear motor is connected to each slider, provided between the guide bars on both sides. 2. The permanent magnet of the linear motor is installed over the moving range of the slider on the base, and the movable part of the linear motor is constituted by a flat coil arranged on the permanent magnet with a predetermined gap. The yoke of the linear motor was formed in a size to cover the installation range of the permanent magnet, the yoke was arranged on the movable portion with a predetermined gap, and both ends were fixed to the base. The linear motor-driven air slide according to claim 1, wherein: 3. The guide bar is formed by a round bar having a circular cross section, and one end of the stage is attached to one of the sliders so as to be movable in a direction perpendicular to the moving direction of the slider. An air slide driven by a linear motor according to claim 1. 4. The air slide driven by a linear motor according to claim 3, wherein one end of the stage is attached to one of the sliders via a linear motion guide.