JP3042467B2 - Thermal stress absorption holding mechanism - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermal stress absorbing / holding mechanism suitable for use, for example, when holding an optical instrument on an equipment stand (optical stand).

[0002]

2. Description of the Related Art Conventionally, this kind of thermal stress absorption holding mechanism is
Various types are employed, for example, as shown in FIGS. 8A and 8B. This will be described with reference to the same drawing. In the same drawing, the thermal stress absorbing and holding mechanism indicated by reference numeral 100 includes a base mounting portion 101 and a thermal stress absorbing portion 102. As a result, a base 104 on which a precision device (not shown) such as an optical device can be mounted on the base 103 is held.

The base mounting portion 101 is composed of two large and small holding shafts 101a and 101b having different outer diameters, and is rotatably held on a thermal stress absorbing portion 102 by a bearing 105. Large-diameter holding shaft 101a of base mount 101
Is located above the thermal stress absorbing portion 102, and the small-diameter holding shaft 101 b is located below the base 104.

The thermal stress absorbing portions 102 are arranged in horizontal directions (X direction and Y direction) orthogonal to each other in the same plane.
The pedestal 10 has through holes 102a and 102b
3 mounted on.

[0005] In the thermal stress absorbing and holding mechanism configured as described above, when the environmental temperature changes, thermal distortion occurs in the pedestal 103 and the base 104 due to a difference in linear expansion coefficient and cross-sectional shape. The base 104 is displaced (relative displacement). That is, when thermal strain occurs in the pedestal 103 and the base 104, the thermal strain acts on the thermal stress absorbing part 102 via the base mounting part 101. At this time, the thermal stress absorbing portion 102 is elastically deformed as shown in FIG.
It tilts in a plane formed by two axes (or two axes of the Y axis and the Z axis), and the thermal stress generated in the pedestal 103 and the base 104 is absorbed.

[0006]

However, in the conventional thermal stress absorbing and retaining mechanism, through holes 102a and 102b are formed in the thermal stress absorbing portion 102 and open in directions orthogonal to each other in the same plane. , So pedestal 1
03 and the base 104 generate thermal strain.
Moved in three axes (X-axis, Y-axis, and Z-axis) directions with respect to the pedestal 103. As a result, the base 104 moves not only in the horizontal direction but also in the vertical direction, that is, a displacement occurs in the height direction, and an optical device such as a laser device or the like that requires high-precision alignment (shown in FIG. However, there is a problem that the method cannot be applied when (1) is retained.

The present invention has been made in view of the above circumstances, and it is possible to prevent the base from being displaced in the height direction even if thermal distortion occurs in the base and the base due to a change in environmental temperature. It is an object of the present invention to provide a thermal stress absorption holding mechanism that can be applied to hold an optical device that requires high-precision alignment.

[0008]

According to a first aspect of the present invention, there is provided a thermal stress absorbing and holding mechanism comprising a leg member for holding a base for mounting equipment on a pedestal. The leg member has a base mounting portion that is restricted in the vertical direction and is movable in the horizontal direction, and a thermal stress absorbing portion that elastically deforms in response to the horizontal movement of the base mounting portion. is there. Therefore, when thermal distortion occurs in the pedestal and the base, the vertical movement of the base mounting portion is restricted, and the thermal stress absorbing portion is elastically deformed in response to the horizontal movement while permitting the horizontal movement. The thermal stress of the pedestal and the base is absorbed.

According to a second aspect of the present invention, in the thermal stress absorbing and holding mechanism according to the first aspect, the base mounting portion is movable in a straight line. Therefore, when thermal distortion occurs in the pedestal and the base, the thermal stress absorbing part elastically deforms in response to this horizontal movement while restricting the vertical movement of the base mounting part and allowing the horizontal and linear movement. Then, thermal stress generated in the pedestal and the base is absorbed.

According to a third aspect of the present invention, in the thermal stress absorbing and retaining mechanism of the first aspect, the base mounting portion is movable in a horizontal plane. Therefore, when thermal distortion occurs in the pedestal and the base, the vertical movement of the base mounting part is restricted, and the thermal stress absorbing part is elastically deformed in response to the horizontal movement while permitting the horizontal movement. ,
Thermal stress generated in the pedestal and the base is absorbed.

According to a fourth aspect of the present invention, in the thermal stress absorbing and holding mechanism according to the first, second or third aspect, a case accommodating the entire thermal stress absorbing portion and a part of the base mounting portion is provided on the base. There is a configuration. Therefore, the entire thermal stress absorbing portion accommodated by the case and a part of the base mounting portion are protected.

According to a fifth aspect of the present invention, there is provided the thermal stress absorbing and holding mechanism according to the fourth aspect, wherein a long hole extending in the direction of linear movement of the base mounting portion is provided in the case, and a pin passing through the long hole is provided. It is configured to be provided on the base mounting part. Therefore, the pin moves in the extending direction of the elongated hole together with the base mounting portion,
In response to this movement, the thermal stress absorbing portion is elastically deformed.

According to a sixth aspect of the present invention, in the thermal stress absorbing and holding mechanism according to the fourth aspect, a pin is provided on the base mounting portion so as to protrude in the horizontal direction, and the pin is guided in the direction of linear movement of the base mounting portion. The sliding mechanism is mounted on the case. Therefore, the pin moves together with the base mounting part in the guide direction of the slide mechanism, and the thermal stress absorbing part is elastically deformed in response to this movement.

The invention according to claim 7 is the invention according to claim 5 or 6.
In the thermal stress absorbing and retaining mechanism described above, a spacer for inserting a pin is interposed between the base mounting portion and the case. Therefore, the horizontal movement except for the linear movement of the base mounting portion is restricted by the spacer interposed between the base mounting portion and the case.

According to an eighth aspect of the present invention, in the thermal stress absorbing and retaining mechanism according to the seventh aspect, the spacer is mounted on one of the base mounting portion and the case. Therefore, horizontal movement excluding linear movement of the base mounting portion is restricted by the base mounting portion or the spacer mounted on the case.

The invention according to claim 9 is the invention according to claim 7 or 8.
In the thermal stress absorbing and retaining mechanism described above, a low friction process is performed between at least one portion between the spacer and the base mounting portion and between the case and the spacer.
Therefore, the movement of the base mounting portion with respect to the case is smoothly performed by the low friction processing performed between the spacer and the base mounting portion and between at least one of the case and the spacer.

According to a tenth aspect of the present invention, in the thermal stress absorption holding mechanism according to any one of the fifth to ninth aspects, the pin is formed of a single pin, and the pin is formed by a pin having a rectangular cross section. There is a configuration. Therefore, the rotation of the base mounting portion is regulated around the pin axis by the single pin.

According to an eleventh aspect of the present invention, in the thermal stress absorbing and holding mechanism according to any one of the fifth to ninth aspects, the pins comprise a plurality of pins arranged in parallel in the direction of linear movement of the base mounting portion. Each pin is formed by a pin having a circular cross section. Therefore, rotation of the base mounting portion in the vertical plane is restricted by the plurality of pins.

The invention according to claim 12 is the invention according to claims 1 to 11
In the thermal stress absorption holding mechanism according to any one of
The thermal stress absorbing portion is made of rubber. Therefore, when thermal distortion occurs in the pedestal and the base, the rubber is elastically deformed in response to this horizontal movement while restricting the vertical movement of the base mounting part and allowing the horizontal movement, and The thermal stress generated in the base is absorbed.

The invention according to claim 13 is the invention according to claims 1 to 11
In the thermal stress absorption holding mechanism according to any one of
The thermal stress absorbing portion is formed of a spring. Accordingly, when thermal distortion occurs in the pedestal and the base, the spring is elastically deformed in response to the horizontal movement while restricting the vertical movement of the base mounting portion and allowing the horizontal movement, and The thermal stress generated in the base is absorbed.

[0021]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described.
This will be described with reference to the drawings. FIGS. 1A and 1B are a front view and a sectional view taken along the line AA of the thermal stress absorbing and holding mechanism according to the first embodiment of the present invention, and FIG. 2 is a sectional view taken along the line BB of FIG. It is. In FIG. 1, an equipment table denoted by reference numeral 1 is a pedestal 2, a thermal stress absorbing and retaining mechanism 3, and a thermal stress non-absorbing and retaining mechanism 4
And a base 5. The pedestal 2 has a flat holding surface 2a.
And are arranged on a horizontal plane.

The thermal stress absorbing and holding mechanism 3 comprises a movable leg member having a base mounting part 6, a thermal stress absorbing part 7, a case 8 and a spacer 9, and is arranged between the pedestal 2 and the base 5. Has been established.

The base mounting portion 6 comprises a base mounting portion which is restricted in vertical movement and is movable in horizontal direction.
Is attached to the lower end surface of the base with an adhesive or the like. Pins 10 and 11 each having a rectangular cross section and projecting along the horizontal direction on opposite sides of the base mounting portion 6 respectively.
Is attached. The surface of each of the pins 10 and 11 is subjected to a low friction treatment by applying, for example, a fluorine resin. Thereby, the movement of each of the pins 10 and 11 in the elongated hole described later is performed smoothly.

The thermal stress absorbing portion 7 is made of, for example, rubber which elastically deforms in response to the horizontal movement of the base mounting portion 6, and is bonded between the lower end surface of the base mounting portion 6 and the bottom inner surface of the case 8. It is interposed by an agent or the like. Thereby, the thermal stress generated in the pedestal 2 and the base 5 is absorbed.

The case 8 is opened upward and has a thermal stress absorbing portion 7.
And a rectangular tube that accommodates a part of the base mounting portion 6 and is interposed between the holding surface 2a of the pedestal 2 and the lower end surface of the thermal stress absorbing portion 7 with an adhesive or the like. This protects the entire thermal stress absorbing section 7 and a part of the base mounting section 6.

The case 8 has a slot 1 extending in the direction of linear movement of the base mounting portion 6 and through which the pins 10 and 11 are inserted.
2 and 13 are provided. Thereby, the base mounting part 6
During the movement, the pins 10 and 11 move in the extending direction of the slots 12 and 13. That is, the vertical movement of the base mounting part 6 is restricted (restricted), and the horizontal movement is allowed.

The spacer 9 is composed of two rectangular cylinders through which the pins 10 and 11 are inserted, and is detachably provided between the pin mounting surface of the base mounting portion 6 and the peripheral edges of the openings of the slots 12 and 13. Have been. As a result, the movement of the base mounting portion 6 in the horizontal and linear direction (± Y direction) is restricted. Further, by attaching and detaching the spacer 9, it is possible to easily change the respective mechanisms of the two-direction (± Y direction and ± Z direction) movement regulation and the one-direction (± Z direction) movement regulation.

A low friction treatment is applied by applying a fluororesin between one open end surface of the spacer 9 and the inner surface of the case 8 and between the pin mounting surface of the base mount 6 and the other end surface of the spacer 9. ing. Thereby, movement of the base mounting part 6 with respect to the case 8 is performed smoothly.

The thermal stress non-absorbing and holding mechanism 4 is composed of fixing leg members arranged in parallel with the thermal stress absorbing and holding mechanism 3, and is disposed between the pedestal 2 and the base 5. The base 5 is held on the pedestal 2 via the thermal stress holding mechanism 3 and the thermal stress non-holding mechanism 4, and precision equipment (not shown) such as optical equipment is placed on the upper surface.

The operation of the thermal stress absorbing and holding mechanism configured as described above will be described with reference to FIGS. 3 (a) and 3 (b). FIGS. 3A and 3B are a local cross-sectional view and an AA cross-sectional view for explaining the operation of the thermal stress absorption holding mechanism according to the first embodiment of the present invention. In FIG. 1A, when thermal strain occurs in the pedestal 2 and the base 5, the base 5 is displaced (relatively displaced) with respect to the pedestal 2 due to a difference in linear expansion coefficient and cross-sectional shape. That is, the base 5 is displaced in the ± X direction with the thermal stress non-absorption holding mechanism 4 as the operation fixed point (origin).

At this time, the spacer 9 and the long holes 12, 1
3 moves in the + X direction, thereby restricting the vertical (± Z direction) and horizontal linear (+ Y direction) movements of the base mount 6, and restricting the horizontal movement. The thermal stress absorbing portion 7 is elastically deformed (bent deformed) in response to the horizontal movement while allowing the movement in the horizontal straight line direction (+ X direction) perpendicular to the horizontal direction, and the thermal stress generated in the base 2 and the base 5 is reduced. Absorbed (reduced). Further, since the cross-sectional shape of each of the pins 10 and 11 is rectangular, the rotation of the base mounting portion 6 around the pin axis is restricted.

On the other hand, the base 5 is displaced in the -X direction (relative displacement) with the thermal stress non-absorption holding mechanism 4 as the operation fixed point (origin).
In this case, since the pins 10 and 11 move in the −X direction, the movement of the base mounting portion 6 in the ± Z direction and the ± Y direction is restricted, and the movement of the base mounting portion 6 in the −X direction is restricted. While allowing, the thermal stress absorbing part 7 is elastically deformed (bending deformation)
Then, the thermal stress generated in the pedestal 2 and the base 5 is absorbed.

Therefore, in the present embodiment, even if thermal distortion occurs in the pedestal 2 and the base 5, it is possible to prevent the base 2 from being displaced in the height direction.

Next, a second embodiment of the present invention will be described with reference to FIG.
This will be described with reference to (a) and (b). FIGS. 4A and 4B are cross-sectional views for explaining the operation of the thermal stress absorbing and holding mechanism according to the second embodiment of the present invention. In FIGS. Therefore, only the operation will be described, and the description of the configuration will be omitted. That is, when thermal strain occurs in the pedestal 2 and the base 5, the base 5 sets the thermal stress non-absorption holding mechanism 4 as an operation fixed point (origin) in the ± X direction and Displacement (relative displacement) with respect to the pedestal 2 in the ± Y direction.

At this time, similarly to the first embodiment, since each of the pins 10 and 11 moves in the ± X direction, the movement of the base mounting portion 6 in the vertical direction (± Z direction) is restricted, and The thermal stress absorbing portion 7 is elastically deformed (bent deformed) in response to the horizontal movement while allowing the movement, and the thermal stress generated in the pedestal 2 and the base 5 is absorbed.

Further, since the spacer 9 is not interposed between the base mounting portion 6 and the case 8, the base mounting portion 6 is allowed to move in the ± Y direction (movement in the opening direction of the elongated holes 12 and 13) while being allowed.
In response to the horizontal movement, the thermal stress absorbing portion 7 is elastically deformed (bent deformed), and the thermal stress generated in the pedestal 2 and the base 5 is absorbed.

Furthermore, the absence of the spacer 9 between the base mounting portion 6 and the case 8 is such that the base 5 rotates around the thermal stress absorbing and holding mechanism 3 with respect to the pedestal 2 in a horizontal plane. In this case, the base mounting part 6 rotates around a vertical line (Z axis) in a horizontal plane,
In response to this rotation, the thermal stress absorbing portion 7 is elastically deformed (torsional deformed), and the thermal stress generated in the pedestal 2 and the base 5 is absorbed.

Since the cross-sectional shape of each of the pins 10 and 11 is rectangular, the rotation of the base mount 6 around the pin axis is restricted as in the first embodiment. Therefore, in the present embodiment, similarly to the first embodiment, even if thermal distortion occurs in the pedestal 2 and the base 5, it is possible to prevent the base 5 from being displaced in the height direction.

In the first and second embodiments, the case where the cross-sectional shape of each of the pins 10 and 11 is rectangular has been described. However, the present invention is not limited to this. As shown in FIG. 5, the cross-sectional shapes of the pins 21 and 22 may be circular. In this case, pin 2
Reference numerals 1 and 22 are attached to the base mounting portion 6 in parallel with the extending direction of the elongated hole 12 (the moving direction of the base mounting portion 6). As a result, the rotation of the base mount 6 in the vertical plane is restricted.

In the first embodiment and the second embodiment, the case where the thermal stress absorbing portion 7 is made of rubber has been described. However, the present invention is not limited to this, and a fourth embodiment is shown in FIG. As described above, the same effects as those of the first embodiment and the second embodiment can be obtained even with a compression coil spring.

Further, in the first embodiment and the second embodiment, the case where the pins 10, 11 move in the extending direction of the elongated holes 12, 13 has been described, but the present invention is not limited to this. Instead, a slide mechanism 41 that guides the pins 10 and 11 (only the pin 10 is shown) in the moving direction of the base mount 6 may be attached to the case 8 as shown in FIG. In this case, the pin 10 moves together with the base mount 6 in the guide direction of the slide mechanism 41,
In response to this movement, the thermal stress absorbing section 7 is elastically deformed.

In the first embodiment, the case where the spacer 9 through which the pins 10 and 11 are inserted is simply interposed between the base mounting portion 5 and the case 8 has been described, but the present invention is not limited to this. Instead, the spacer 9 may be attached to one of the base attachment portion 5 and the case 8. In this case, for example, a fluorine resin is applied to at least one portion between the spacer 9 and the base mounting portion 5 and between the case 8 and the spacer 9 to perform a low friction treatment, so that the base mounting portion 6 Is smoothly carried out.

[0043]

As described above, according to the present invention, the leg member for holding the base for mounting the equipment on the pedestal is restricted in the vertical direction and can be moved in the horizontal direction. And a thermal stress absorbing portion that elastically deforms in response to the horizontal movement of the base mounting portion, so that when thermal distortion occurs in the pedestal and the base, the vertical movement of the base mounting portion is restricted. In response to the horizontal movement, the thermal stress absorbing portion elastically deforms in response to the horizontal movement, thereby absorbing the thermal stress generated in the pedestal and the base.

Therefore, even if thermal distortion occurs in the pedestal and the pedestal due to a change in environmental temperature, it is possible to prevent the displacement of the pedestal in the height direction. This can be applied to a case where an optical device such as the above is held.

[Brief description of the drawings]

FIGS. 1A and 1B are a front view and a cross-sectional view taken along the line AA, respectively, showing a thermal stress absorbing and holding mechanism according to a first embodiment of the present invention.

FIG. 2 is a sectional view taken along line BB of FIG. 1 (b).

FIGS. 3A and 3B are a local cross-sectional view and an AA cross-sectional view for explaining the operation of the thermal stress absorption holding mechanism according to the first embodiment of the present invention.

FIGS. 4A and 4B are cross-sectional views illustrating an operation of a thermal stress absorption holding mechanism according to a second embodiment of the present invention.

FIG. 5 is a front view showing a thermal stress absorbing and holding mechanism according to a third embodiment of the present invention.

FIG. 6 is a cross-sectional view illustrating a thermal stress absorption holding mechanism according to a fourth embodiment of the present invention.

FIG. 7 is a front view showing a thermal stress absorbing and holding mechanism according to a fifth embodiment of the present invention.

FIGS. 8A and 8B are a front view and a sectional view taken along line AA of a conventional thermal stress absorbing and holding mechanism.

FIG. 9 is a front view for explaining the operation of the conventional thermal stress absorption holding mechanism.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Device stand 2 Base 3 Thermal stress absorption holding mechanism 5 Base 6 Base mounting part 7 Thermal stress absorption part 8 Case 9 Spacer 10, 11 pin 12, 13 Slot

Claims (13)

(57) [Claims] 1. A leg member for holding a base for mounting equipment on a pedestal, the leg member being restricted in vertical movement and movable in a horizontal direction; A thermal stress absorbing and holding mechanism, comprising: a thermal stress absorbing portion that elastically deforms in response to the horizontal movement of the base mounting portion. 2. The thermal stress absorbing and holding mechanism according to claim 1, wherein said base mounting portion is movable in a straight line direction. 3. The thermal stress absorbing and holding mechanism according to claim 1, wherein the base mounting portion is movable in a horizontal plane. 4. The thermal stress absorption holding device according to claim 1, wherein a case for housing the entirety of the thermal stress absorbing portion and a part of the base mounting portion is arranged on the pedestal. mechanism. 5. The base mounting portion, wherein a long hole extending in the direction of linear movement of the base mounting portion is provided in the case, and a pin passing through the long hole is provided in the base mounting portion. The thermal stress absorption holding mechanism according to the above. 6. The base mounting portion is provided with a pin projecting in a horizontal direction, and a slide mechanism for guiding the pin in a linear movement direction of the base mounting portion is provided in the case. Item 6. The thermal stress absorbing and retaining mechanism according to Item 4. 7. The thermal stress absorbing and retaining mechanism according to claim 5, wherein a spacer through which the pin is inserted is interposed between the base mounting portion and the case. 8. The thermal stress absorbing and retaining mechanism according to claim 7, wherein the spacer is attached to one of the base attachment portion and the case. 9. The thermal stress absorbing mechanism according to claim 7, wherein a low friction treatment is performed between the spacer and the base mounting portion and between at least one of the case and the spacer. 10. The thermal stress absorbing / holding mechanism according to claim 5, wherein said pin comprises a single pin, and said pin is formed by a pin having a rectangular cross section. 11. The apparatus according to claim 5, wherein said pins comprise a plurality of pins arranged in parallel in a direction of linear movement of said base mounting portion, and each of said pins is formed by a pin having a circular cross section. The thermal stress absorption holding mechanism according to any one of the above. 12. The thermal stress absorbing and retaining mechanism according to claim 1, wherein said thermal stress absorbing portion is made of rubber. 13. The thermal stress absorbing and retaining mechanism according to claim 1, wherein said thermal stress absorbing portion comprises a spring.