JPH05246398A - Drive mechanism element - Google Patents

Abstract

PURPOSE:To provide drive mechanism elements having long life as well as being positioned with high accuracy under severe environment where large temperature change is generated receiving radiant heat. CONSTITUTION:A group of machine elements 4, 5, 6, 7 of a drive mechanism part is fixed in the state of being insulated from the outer wall 1 of the drive mechanism part, and temperature control means and insulating means are provided to make the temperature of the group of machine elements 4, 5, 6, 7 be within the target range. Accordingly, even if the temperature of the machine element part is heated receiving radiant heat, the temperature change of the elements can be set within the target range. Also the contact part gap of the machine element group is made the minimum to reduce the contact surface pressure of the contact parts to the allowed value or less. This results in obtaining high accuracy and long life.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a manipulator driving mechanism element used in an environment receiving radiant heat from one side, and a drive suitable for wafer handling of a space manipulator used in a vacuum environment and a semiconductor manufacturing apparatus. Regarding mechanical elements.

[0002]

2. Description of the Related Art Conventionally, there are few manipulators used in a vacuum environment, and there is only a wafer handling mechanism in a vacuum chamber of a semiconductor manufacturing apparatus or the like and a mechanism for introducing power into the chamber. As a wafer handling mechanism, there is a structure shown in "Substrate holder" of Japanese Patent Laid-Open No. 62-285413. In this apparatus, the mechanism section is heated to 200 ° C. or higher by the radiant heat of the vapor deposition source, and there is concern that seizure of the bearing or the like in the mechanism section may occur. In the conventional art, in such a case, a seizure is prevented by setting a gap of a contact sliding portion such as a bearing or a gear larger than usual.

Recently, a high-performance manipulator used in outer space has been developed. However, the conventional space manipulator does not have high driving accuracy and has a short required life. Therefore, the gap between the mechanical elements is enlarged, or lubricating oil is applied so that the mechanical element can be driven in a short time even if the gap is small.

FIG. 11 is a longitudinal sectional view showing the structure of a drive mechanism element of a conventional space manipulator.

[0005]

In the currently planned high-precision manipulator for outer space specifications, as shown in FIG. 11, a heat shield cover 34 is provided outside the manipulator in order to suppress radiant heat intrusion from the outside. thinking. However, with such a configuration, the manipulator cannot be driven with high precision in a vacuum for a long period of time. Moreover, the heat shield cover 3 is provided on the outer periphery of the manipulator.
The provision of 4 limits the operating range of the manipulator.

Further, although the recent wafer handling apparatus requires high-accuracy wafer positioning, such a conventional technique cannot satisfy the requirement.

In view of the above problems, it is an object of the present invention to provide a drive mechanism element which has high positioning accuracy and can be used for a long period of time even in a severe environment where radiant heat is received and the temperature changes drastically. ..

[0008]

SUMMARY OF THE INVENTION The above-mentioned object is to provide a driving means which is connected to and driven by a driven body under the environment of receiving radiant heat, and one of which is slidably connected to the driven body and the other of which is an extension body. This is achieved by providing an outer wall of the driving means that is fixed to the outer wall of the driving means and that is fixed to the outer wall of the driving means by a heat insulating material.

[0009] The above-mentioned object is to provide a driving means which is connected to and driven by a driven body under a vacuum environment receiving radiant heat, and one of which is slidably connected to the driven body and the other of which is fixed to an extension body for heat reflection. This is achieved by providing a drive means outer wall made of a material and a drive means fixing member made of a heat insulating material for fixing the drive means to the drive means outer wall.

The above object is achieved by the fact that the driving means fixing member is an FRP having a heat insulating property.

The above object is achieved by the FRP having a dual cone structure. The above-mentioned object is that the driving means is a motor, a speed reducer in which an input shaft is engaged with one shaft of the motor and an output shaft is connected to the driven body, and a braking mechanism provided in the other extension shaft of the motor. And a rotation sensor.

The above-mentioned object is achieved by the outer wall of the driving means being composed of a member made of a small-diameter rod-shaped material and having a structural strength, and a heat shield plate surrounding the outer periphery of the member having a structural strength.

The above object is to provide a temperature sensor for detecting the temperature of the drive means and the outer wall of the drive means, and a temperature control means for controlling the temperature of the drive means and the outer wall of the drive means by a detection signal of the temperature sensor. It is achieved by

The above-mentioned object is that the temperature control means uses a Peltier element for thermally connecting the driving means and the outer wall of the driving means, a power supply for supplying a current to the Peltier element, and a detection signal of the temperature sensor. And a switching device for switching the direction of the current supplied to the Peltier device.

The above object is achieved by arranging a surface-treated portion in which a part of the outer wall of the driving means is subjected to surface treatment so as to be at room temperature and a bimetal between the surface-treated portion and the driving means. It

The above object is to provide a high-temperature surface-treated part in which a part of the outer wall of the driving means is surface-treated so as to have a high temperature, and a first bimetal arranged between the high-temperature surface-treated part and the driving means. And a second bimetal disposed between the low temperature surface treatment section and the driving means, the low temperature surface treatment section being surface-treated so as to have a low temperature.

[0017]

According to the above construction, the radiant heat entering from one side is reflected by the outer wall of the driving means made of a heat reflecting material, and the driving means is fixed to the outer wall of the driving means via the driving means fixing member made of a heat insulating material. Since the amount of heat entering from the outside is extremely small and the temperature change of the outer wall of the driving means is small, the deformation due to the temperature change of the outer wall of the driving means is also small and the gap between the outer wall of the driving means and the driven body can be made small and the positioning accuracy can be improved. Becomes higher. Further, by reducing the surface pressure of the contact portion between the outer wall of the driving means and the driven body, which is caused by the deformation due to the temperature change, to the allowable value or less, damage or wear of the contact surface can be prevented and the device can be used for a long time.

In a vacuum environment, heat transfer due to convection does not exist, and the means for reducing the penetration of heat due to radiation and conduction has the effect of reducing the temperature change between the elements constituting the drive mechanism element.

When FRP is used for the driving means fixing member, it has a high heat insulating property and a high specific strength, which is advantageous for transportation to outer space.

A driving means such as a motor or a brake which generates a large amount of heat is fixed to the outer wall of the driving means via a heat insulating driving means fixing member, and the heat of the driving means is radiated to the outside by the temperature control means. As a result, it is possible to reduce the temperature change between the respective elements constituting the drive mechanism element.

When the temperature of the driving means is extremely lowered and the function cannot be obtained, the temperature control means takes in external heat from the outer wall of the driving means via the heat conduction path and keeps the temperature of the driving means at a predetermined value. However, the function of the driving means can be restored.

[0022]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a sectional view showing the structure of an embodiment of the present invention.

This figure shows a cross section of a joint mechanism that relatively moves in the circumferential direction of a high precision manipulator used in outer space. In the figure, as a mechanical element group for joints, a motor 4, a speed reducer 5, a brake 6 and a rotation sensor 7 are coaxially arranged in series, and the rotational force of the motor 4 is reduced by the speed reducer 5 to drive the driven member 2. To rotate. Each of these mechanical element groups is fixed to the joint outer wall 1 connected to the manipulator boom 3 by a fixing heat insulating material 8. With this structure, radiant heat from the sun can be reduced from entering the mechanical element group.

Further, when the manipulator is in an orbital position where the temperature becomes extremely low so that it does not receive heat radiation from the sun, for example, at the position of the shadow of the earth, the heat insulating structure as in this embodiment is used to reduce the mechanical force inside the joint. It is also possible to prevent the element group from becoming supercooled. As a result, the temperature change of the mechanical elements such as bearings and gears can be minimized, so that the gap can be set small and a high-precision manipulator with high positioning accuracy can be realized.

If this embodiment is applied to a driving mechanism used in a vacuum environment such as a semiconductor manufacturing apparatus, it will not be heated to a high temperature by heat radiation from a molecular beam source or other vapor deposition sources. It is possible to maintain high reliability of the drive mechanism.

FIG. 2 is a sectional view when a dual cone type is used as the fixing heat insulating material in FIG. Here, the dual cone is one in which one or a plurality of thin plate conical bodies are overlapped with each other and arranged concentrically with respect to the cylindrical joint outer wall 1 of the manipulator. As a material for this member, for example, a polymer material such as FRP is suitable in terms of heat insulation and specific strength. In the dual cone type heat insulation fixing member 9 in this figure, the thin plate conical body is
Combined to form one cone type. With this structure, the heat invasion path can be lengthened, so that the thermal resistance is increased and the amount of heat entering can be reduced.
Further, since the pair of cone-shaped members are arranged to face each other, the mechanical element parts such as the motor 4 can be supported with high rigidity against the outer wall of the joint. With the above configuration, since the temperature of the machine element parts can be supported almost stably with almost constant temperature, the positioning accuracy is high and the thermal stress applied to the bearing 10 is small, so that the joint mechanism for the manipulator or the drive mechanism for the semiconductor manufacturing device that can be used for a long time Can be provided.

FIG. 3 is a sectional view showing a structure for fixing the dual cone type fixing member 9 shown in FIG. 2 to the joint outer wall 1. 36 in the figure is the dual cone type fixing member 9 described above.
Is a fixing jig for finely adjusting and fixing the position with respect to the outer joint wall 1. With this structure, the relative position of each mechanical element can be finely adjusted and fixed to the outer joint wall 1.
FIG. 4 is a perspective view of a structural member / heat shield cover suitable for an outer wall of a drive mechanism such as a joint used in a vacuum. The structure part is constituted by the small-diameter rod-shaped material 31 or the ring-shaped material 32, and the periphery thereof is covered with a heat shield plate 33 having a heat shield function. With this structure, the outer wall of the mechanical element can be lightened while maintaining the structural strength,
It is especially suitable for drive mechanisms such as joints for space manipulators.

FIG. 5 is a sectional view showing a structure provided with temperature control means for controlling the temperature of the mechanical element shown in FIG. 1 to be constant. The temperature control unit 11 controls the function of moving the heat on the high temperature side to the low temperature side. Specifically, the temperature sensor 14 for detecting the temperature Te of the mechanical element portion and the temperature Tm of the outer wall of the joint.
And the two temperature values Te and Tm and the temperature T of the mechanical element
The temperature range in which e is to be set Tmin, Tmax (Tmin <Te <Tma
x) is compared, and has the function of switching the flow direction of the heat so that the heat moves from the high temperature side to the low temperature side under the following conditions.

Here, the conditions are as follows: 1) In the case of Te> Tm: Te> Tmax and heat is radiated from the mechanical element to the outer wall of the joint.

When Te <= Tmax, the heat radiation from the mechanical element to the outer wall of the joint is stopped.

2) In the case of Te <Tm When Te> = Tmin, heat input from the outer wall of the joint to the mechanical element is stopped.

When Te <Tmin, heat is applied to the mechanical element portion from the outer wall of the joint.

Further, 12a and 12b in the figure are heat conducting paths for thermally connecting the mechanical element part and the temperature control part 11 and the temperature control part 11 and the outer wall part of the joint. Further, the good thermal conductor 13 arranged in an annular shape on a part of the outer wall surface of the joint, and the room temperature treated surface 13a having a high emissivity on the surface of the good thermal conductor 13 and having the temperature lowered by the radiation to reach the normal temperature
The heat resistance between the mechanical element portion and the outer wall of the joint is reduced by providing the portion, and the temperature of the mechanical element can be controlled by quickly radiating heat from the mechanical element that generates a lot of heat, for example, the brake 7.

With the above configuration, the temperature of the mechanical element inside the joint of the manipulator can be set to a state close to the normal temperature range on the earth, so that the manipulator can be operated without problems even if the gap of the mechanical element is set small. You can
Of course, even if this mechanism is used for a mechanism driven in a vacuum environment such as a semiconductor manufacturing apparatus, the effect can be sufficiently exhibited.

FIG. 6 is a cross-sectional view showing the structure when a Peltier element unit is used as the heat conduction path of FIG.

FIG. 7 is a sectional view showing the detailed structure of the Peltier device unit 22 of FIG.

As shown in the figure, a Peltier element 23 is arranged between the mechanical element portion and the outer wall 1 of the joint via an electric insulating material 24 and a terminal plate 25. Further, temperature sensors 30 for measuring the temperature of the mechanical element parts and the temperature of the outer wall of the joint are respectively attached and connected to the controller 27. Controller 2
7 controls the current switch 29 to change the current direction so that the heat flow direction changes depending on the above temperature conditions.
Alternatively, the power supply 28 is turned on and off. Peltier element 23
The mechanical element that thermally couples the
For example, the motor 4 and the brake 6 shown in FIG. 5 are preferable.

FIG. 8 is a sectional view showing a structure in which a bimetal is used instead of the Peltier device unit shown in FIG.
Reference numeral 15 in the figure is a bimetal.

FIG. 9 is a sectional view showing details of the bimetal of FIG. When the combination of the materials of the bimetal 15 is configured to be deformed leftward as shown in the figure when the temperature rises, the left side of the contact protrusion 17 is contacted. On the contrary, when the temperature becomes low, the right side portion of the contact protrusion 17 is contacted because it is deformed rightward. The contact protrusions 17 are made of a good conductor of heat, and the outside surface of the contact protrusions 17 is provided with a room temperature treated surface 16 that has been subjected to a surface treatment so that the temperature becomes room temperature. For example, as a surface treatment method in outer space, black paint may be applied. As a result, when the mechanical element portion such as the motor 4 generates heat and exceeds the upper limit of the target temperature range, the bimetal 15 comes into contact with the left side of the contact protrusion 17 to form a heat flow path, thereby reducing the temperature of the mechanical element portion. Can be lowered. Further, when the temperature of the mechanical element part falls too much and exceeds the lower limit value of the target temperature range due to long-term operation stop, the bimetal 15 deforms to the right and contacts the right side of the contact protrusion 17. As a result, the heat flow path is formed again, so that heat input from the outer wall of the joint flows into the mechanical element portion and the temperature of the mechanical element portion can be increased.

Further, the heater 18 in this figure is for heating the mechanical element portion when the joint does not receive the radiant heat of the sun for a long period of time in outer space. The controller 19 turns the source 20 on and off according to the detected value of the temperature sensor 21 that monitors the temperature of the mechanical element part.
As a result, it is possible to prevent abnormal temperature drop of the mechanical element part.

FIG. 10 is a sectional view showing the details of the bimetal of another embodiment. The outer wall of the joint is provided with a low temperature constant treatment surface 38 which is treated so that the surface temperature becomes constant at low temperature, and a high temperature constant treatment surface 39 which is treated so as to be constant at high temperature. Further, there are protrusions 17a and 17b on the inner surfaces of the surface-treated portions 38 and 39, and bimetals 15 having the same structure and the same size are arranged between the protrusions and the mechanical element portions, respectively. To conduct heat.

As the surface treatment units 38 and 39, when the drive mechanism is used in outer space, a white paint is applied as a surface treatment method for keeping a low temperature and a surface treatment for keeping a high temperature. Aluminum vapor deposition is a suitable method. With this configuration, when the mechanical element exceeds the upper limit of the target temperature range, the left bimetal 1
5 deforms to the left and contacts the protrusion 17a. As a result, heat is conducted through the bimetal 15 and is transferred from the mechanical element section to the processing section 38 that has been surface-treated so as to be constant at a low temperature, and is radiated to outer space to lower the temperature of the mechanical element section. Further, when the temperature of the mechanical element portion falls below the lower limit of the target temperature range, the right bimetal 15 is deformed to the right and comes into contact with the protrusion 17b. As a result, heat is conducted from the surface treatment portion 39, which has been treated so as to be constant at high temperature, through the bimetal 15 on the right side and flows into the mechanical element portion to raise the temperature of the element portion. That is, according to the present embodiment, the temperature of the mechanical element portion left in a vacuum can be set within a certain target temperature range, and as a result, the temperature change of the element portion can be reduced and a highly reliable drive mechanism can be realized. be able to.

[0044]

According to the present invention, unnecessary radiant heat that invades is reflected by the outer wall of the driving means and the driving means is fixed to the outer wall of the driving means via a heat insulating material, so that the amount of heat entering from the outside becomes extremely small. Since the temperature change of the outer wall of the means becomes small, the gap between the outer wall of the driving means and the driven body can be made small, and the positioning accuracy becomes high. Further, by reducing the surface pressure of the contact portion between the outer wall of the driving means and the driven body, which is caused by the deformation due to the temperature change, to the allowable value or less, damage or wear of the contact surface can be prevented and the device can be used for a long time.

By providing means for controlling heat transfer between the drive means and the outer wall of the drive means, the temperature of the outer wall of the drive means inside the drive mechanism element is maintained at a predetermined value, and the drive mechanism element is constructed. It is possible to reduce the temperature change between the respective elements.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a configuration of an exemplary embodiment of the present invention.

FIG. 2 is a cross-sectional view when a dual cone type is used as the fixing heat insulating material in FIG.

FIG. 3 is a cross-sectional view showing a structure for fixing the dual cone type fixing member shown in FIG. 2 to an outer joint wall.

FIG. 4 is a perspective view of a structural member / heat shield cover suitable for the outer wall of the drive mechanism according to the embodiment of the present invention.

5 is a cross-sectional view showing a configuration provided with temperature control means for controlling the temperature of the mechanical element shown in FIG. 1 to be constant.

FIG. 6 is a cross-sectional view showing the configuration when a Peltier element unit is used as the heat conduction path in FIG.

7 is a sectional view showing a detailed configuration of the Peltier device unit of FIG.

8 is a cross-sectional view showing a configuration in the case where a bimetal is used instead of the Peltier device unit of FIG.

9 is a cross-sectional view showing details of the bimetal of FIG.

FIG. 10 is a sectional view showing details of a bimetal according to another embodiment of the present invention.

FIG. 11 is a sectional view showing a configuration of a conventional drive mechanism element.

[Explanation of symbols]

 1 outer wall of joint part 2 driven member 3 manipulator boom 4 motor 5 speed reducer 6 brake 7 rotation sensor 8 heat insulating material for fixing 9 dual cone type heat insulating fixing material 10 bearing 11 temperature control part 12a heat conduction path 12b heat conduction path 13 good heat conductor 13a Room Temperature Treatment Surface 14 Temperature Sensor 15 Bimetal 16 Room Temperature Treatment Surface 17 Contact Protrusion 17a Protrusion 17b Protrusion 18 Heater 19 Controller 20 Power Supply 21 Temperature Sensor 22 Peltier Element Unit 23 Peltier Element 24 Insulating Material 25 Terminal Board 27 Controller 28 Power Supply 29 Current switcher 30 Temperature sensor 31 Small-diameter rod-shaped material 32 Ring-shaped material 33 Heat shield plate 34 Heat shield cover 36 Dual cone member fixing jig 37 Heat insulation material 38 Low temperature constant treatment surface 39 High temperature constant treatment surface

[Procedure amendment]

[Submission date] December 2, 1992

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] Claim 10

[Correction method] Change

[Correction content]

[Procedure Amendment 2]

[Document name to be amended] Statement

[Name of item to be amended] Detailed explanation of the invention

[Correction method] Change

[Correction content]

DETAILED DESCRIPTION OF THE INVENTION

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a manipulator driving mechanism element used in an environment receiving radiant heat from one side, and a drive suitable for wafer handling of a space manipulator used in a vacuum environment and a semiconductor manufacturing apparatus. Regarding mechanical elements.

2. Description of the Related Art Conventionally, there are few manipulators used in a vacuum environment, and there is only a wafer handling mechanism in a vacuum chamber of a semiconductor manufacturing apparatus or the like and a mechanism for introducing power into the chamber. As a wafer handling mechanism, there is a structure shown in "Substrate holder" of Japanese Patent Laid-Open No. 62-285413. In this apparatus, the mechanism section is heated to 200 ° C. or higher by the radiant heat of the vapor deposition source, and there is concern that seizure of the bearing or the like in the mechanism section may occur. In the conventional art, in such a case, a seizure is prevented by setting a gap of a contact sliding portion such as a bearing or a gear larger than usual. Recently, high-performance manipulators used in outer space have been developed, but conventional space manipulators do not have very high driving accuracy and the required life is short. Therefore, the gap between the mechanical elements is enlarged, or lubricating oil is applied so that the mechanical element can be driven in a short time even if the gap is small. FIG. 11 is a vertical cross-sectional view showing the structure of a drive mechanism element of a conventional space manipulator.

In the currently planned high-precision manipulator for outer space specifications, as shown in FIG. 11, a heat shield cover 34 is provided outside the manipulator in order to suppress radiant heat intrusion from the outside. thinking. However, with such a configuration, the manipulator cannot be driven with high precision in a vacuum for a long period of time. Moreover, the heat shield cover 3 is provided on the outer periphery of the manipulator.
The provision of 4 limits the operating range of the manipulator. Further, although recent wafer handling apparatuses require highly accurate wafer positioning, such requirements cannot be satisfied by such conventional techniques. In view of the above problems, an object of the present invention is to provide a drive mechanism element that has high positioning accuracy and can be used for a long period of time even in a severe environment where radiant heat is received and the temperature changes drastically.

SUMMARY OF THE INVENTION The above-mentioned object is to provide a driving means which is connected to and driven by a driven body under the environment of receiving radiant heat, and one of which is slidably connected to the driven body and the other of which is an extension body. This is achieved by providing an outer wall of the driving means that is fixed to the outer wall of the driving means and that is fixed to the outer wall of the driving means by a heat insulating material. The above-mentioned object is composed of a driving means which is connected to and driven by a driven body under a vacuum environment receiving radiant heat, and one of which is slidably connected to the driven body and the other is fixed to an extension body and which comprises a heat reflecting material. This is achieved by providing an outer wall of the driving means and a driving means fixing member made of a heat insulating material for fixing the driving means to the outer wall of the driving means. The above object is achieved by the driving means fixing member being an FRP having a heat insulating property. The above object is achieved by the FRP having a dual cone structure. The above-mentioned object is that the driving means is a motor, a speed reducer in which an input shaft is engaged with one shaft of the motor and an output shaft is connected to the driven body, and a braking mechanism provided in the other extension shaft of the motor. And a rotation sensor. The above object is achieved by the outer wall of the driving means being composed of a member made of a small-diameter rod-shaped material and having structural strength, and a heat shield plate surrounding the outer periphery of the member having structural strength. The above object is achieved by providing a temperature sensor for detecting the temperature of the drive means and the outer wall of the drive means, and a temperature control means for controlling the temperature of the drive means and the outer wall of the drive means by a detection signal of the temperature sensor. To be done. The above-mentioned object is that the temperature control means comprises a Peltier element for thermally connecting the driving means and the outer wall of the driving means, a power supply for supplying a current to the Peltier element, and a detection signal of the temperature sensor for the Peltier element. And a switching device for switching the direction of the current supplied to. The above-mentioned object can be achieved by disposing a surface treatment part in which a part of the outer wall of the driving means is subjected to a surface treatment so that the temperature is normal temperature, and a bimetal is arranged between the surface treatment part and the driving means. The above-mentioned object is: a high temperature surface treatment part in which a part of the outer wall of the driving means is subjected to a surface treatment so as to have a high temperature; a first bimetal disposed between the high temperature surface treatment part and the driving means; And a second bimetal disposed between the low temperature surface treatment section and the driving means.

According to the above construction, the radiant heat entering from one side is reflected by the outer wall of the driving means made of a heat reflecting material, and the driving means is fixed to the outer wall of the driving means via the driving means fixing member made of a heat insulating material. Since the amount of heat entering from the outside is extremely small and the temperature change of the outer wall of the driving means is small, the deformation due to the temperature change of the outer wall of the driving means is also small and the gap between the outer wall of the driving means and the driven body can be made small and the positioning accuracy can be improved. Becomes higher. Further, by reducing the surface pressure of the contact portion between the outer wall of the driving means and the driven body, which is caused by the deformation due to the temperature change, to the allowable value or less, damage or wear of the contact surface can be prevented and the device can be used for a long time. In a vacuum environment, there is no heat transfer due to convection, and the means for reducing the penetration of heat due to radiation and conduction has the effect of reducing the temperature change between the elements constituting the drive mechanism element. FRP on the driving means fixing member
Since it has high heat insulation and high specific strength, it is advantageous for transportation to outer space. Driving is performed by fixing the driving means such as a motor and brake, which generates a large amount of heat, to the outer wall of the driving means via a heat insulating driving means fixing member, and radiating the heat generated by the driving means to the outside by the temperature control means. It is possible to reduce the temperature change between each element constituting the mechanical element. When the temperature of the driving means is extremely lowered and the function cannot be obtained, the temperature control means takes in external heat from the outer wall of the driving means through the heat conduction path and keeps the temperature of the driving means at a predetermined value to drive it. The function of the means can be restored.

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a sectional view showing the structure of an embodiment of the present invention.
This figure shows the cross section of the joint mechanism that makes relative movement in the circumferential direction of the high precision manipulator used in outer space. In the figure, as a mechanical element group for joints, a motor 4, a speed reducer 5, a brake 6 and a rotation sensor 7 are coaxially arranged in series, and the rotational force of the motor 4 is reduced by the speed reducer 5 to drive the driven member 2. To rotate. Each of these mechanical element groups is fixed to the joint outer wall 1 connected to the manipulator boom 3 by a fixing heat insulating material 8. With this structure, radiant heat from the sun can be reduced from entering the mechanical element group. Further, when the manipulator is in an orbital position where the temperature becomes extremely low so that it does not receive heat radiation from the sun, for example, at the position of the shadow of the earth, the mechanical element group inside the joint is made by the heat insulating structure as in this embodiment. It can also prevent a supercooled state. As a result, the temperature change of the mechanical elements such as bearings and gears can be minimized, so that the gap can be set small and a high-precision manipulator with high positioning accuracy can be realized. If this embodiment is adopted as a driving mechanism used in a vacuum environment such as a semiconductor manufacturing apparatus, the driving mechanism is not heated to a high temperature even by heat radiation from a molecular beam source or other vapor deposition sources. The reliability of can be maintained high. FIG. 2 is a sectional view when a dual cone type is used as the fixing heat insulating material in FIG. Here, the dual cone is one in which one or a plurality of thin plate conical bodies are overlapped with each other and arranged concentrically with respect to the cylindrical joint outer wall 1 of the manipulator. As a material for this member, for example, a polymer material such as FRP is suitable in terms of heat insulation and specific strength. In the dual cone type heat insulation fixing member 9 in this figure, three thin plate conical bodies are combined to form one cone type. With this structure, the heat invasion path can be lengthened, so that the thermal resistance is increased and the amount of heat entering can be reduced. Further, since the pair of cone-shaped members are arranged to face each other, the mechanical element parts such as the motor 4 can be supported with high rigidity against the outer wall of the joint. With the above configuration, since the temperature of the machine element parts can be supported almost stably with almost constant temperature, the positioning accuracy is high and the thermal stress applied to the bearing 10 is small, so that the joint mechanism for the manipulator or the drive mechanism for the semiconductor manufacturing device can be used for a long time Can be provided. FIG. 3 is FIG.
It is sectional drawing which showed the structure which fixes the dual-cone type fixing member 9 shown in FIG. Reference numeral 36 in the figure is a fixing jig for finely adjusting and fixing the position of the dual cone type fixing member 9 to the joint outer wall 1. With this structure, the relative position of each mechanical element can be finely adjusted and fixed to the outer joint wall 1. FIG. 4 is a perspective view of a structural member / heat shield cover suitable for an outer wall of a drive mechanism such as a joint used in a vacuum. The structure part is constituted by the small-diameter rod-shaped material 31 or the ring-shaped material 32, and the periphery thereof is covered with a heat shield plate 33 having a heat shield function. This structure makes it possible to reduce the weight of the outer wall of the mechanical element while maintaining the structural strength, and thus is particularly suitable for a drive mechanism such as a joint for a space manipulator. FIG. 5 is a sectional view showing a structure provided with temperature control means for controlling the temperature of the mechanical element shown in FIG. 1 to be constant. The temperature control unit 11 controls the function of moving the heat on the high temperature side to the low temperature side. Specifically, the temperature sensor 14 for detecting the temperature Te of the mechanical element portion and the temperature Tm of the outer joint wall and the two temperature values Te, Tm thereof.
And the temperature range Tmin in which the temperature Te of the mechanical element is desired to be set,
It has a function of comparing Tmax (Tmin <Te <Tmax) and switching the flow direction of the heat so that the heat moves from the high temperature side to the low temperature side under the following conditions. Here, the conditions are: 1) In the case of Te> Tm, Te> Tmax and heat is radiated from the mechanical element portion to the outer wall of the joint. When Te <= Tmax, the heat radiation from the mechanical element to the outer wall of the joint is stopped. 2) In the case of Te <Tm When Te> = Tmin, heat input from the outer wall of the joint to the mechanical element is stopped. When Te <Tmin, heat is applied to the mechanical element from the outer wall of the joint. Further, 12a and 12b in the figure are heat conduction paths that thermally connect the mechanical element section and the temperature control section 11 and the temperature control section 11 and the joint outer wall section. Further, the good thermal conductor 13 arranged in an annular shape on a part of the outer wall surface of the joint, and the room temperature treated surface 13a having a high emissivity on the surface of the good thermal conductor 13 and having the temperature lowered by the radiation to reach the normal temperature A section,
It is possible to reduce the heat resistance between the mechanical element portion and the outer wall of the joint, and dissipate heat more quickly than the mechanical element that generates a large amount of heat, for example, the brake 7 to control the temperature of the mechanical element. With the above configuration,
Since the temperature of the mechanical element inside the joint of the manipulator can be set to a state close to the normal temperature range on the earth, the manipulator can be operated without any problem even if the gap of the mechanical element is set small. Of course, even if this mechanism is used for a mechanism driven in a vacuum environment such as a semiconductor manufacturing apparatus, the effect can be sufficiently exhibited. FIG. 6 is a cross-sectional view showing a configuration in which a Peltier element unit is used as the heat conduction path in FIG.
FIG. 7 is a sectional view showing a detailed configuration of the Peltier device unit 22 of FIG. As shown in the figure, a Peltier element 23 is arranged between the mechanical element part and the outer wall 1 of the joint via an electric insulating material 24 and a terminal plate 25. Also, a temperature sensor 30 for measuring the temperature of the mechanical element parts and the temperature of the outer wall of the joint.
Are respectively attached and connected to the controller 27. The controller 27 controls the current switch 29 to change the current direction or turns the power supply 28 on and off so that the heat flow direction changes depending on the temperature condition. The mechanical element that thermally connects the Peltier element 23 is preferably a mechanical element that generates a large amount of heat, such as the motor 4 and the brake 6 shown in FIG.
FIG. 8 is a cross-sectional view showing a configuration in the case where a bimetal is used instead of the Peltier device unit of FIG. 15 in this figure
Is a bimetal. FIG. 9 is a cross-sectional view showing details of the bimetal of FIG. The combination of materials of bimetal 15
When it is configured to be deformed to the left as shown in the figure when the temperature becomes high, the contact protrusion 17 comes into contact with the left side. On the contrary, when the temperature becomes low, the right side portion of the contact protrusion 17 is contacted because it is deformed rightward. The contact protrusions 17 are made of a good conductor of heat, and the outside surface of the contact protrusions 17 is provided with a room temperature treated surface 16 that has been subjected to a surface treatment so that the temperature becomes room temperature. For example, as a surface treatment method in outer space, black paint may be applied. As a result, when the mechanical element portion such as the motor 4 generates heat and exceeds the upper limit of the target temperature range, the bimetal 15 comes into contact with the left side of the contact protrusion 17 to form a heat flow path, thereby reducing the temperature of the mechanical element portion. Can be lowered. Further, when the temperature of the mechanical element part falls too much and exceeds the lower limit value of the target temperature range due to long-term operation stop, the bimetal 15 deforms to the right and contacts the right side of the contact protrusion 17. By forming a heat flow path again by this, the heat input from the outer wall of the joint flows to the mechanical element part,
The temperature of the mechanical element can be raised. Further, the heater 18 in this figure is for heating the mechanical element portion when the joint does not receive the radiant heat of the sun for a long period of time in outer space, for example. Based on the detection value of the temperature sensor 21 that monitors the temperature of the mechanical element, the controller 1
9 turns the source 20 on and off. As a result, it is possible to prevent abnormal temperature drop of the mechanical element part. FIG. 10 is a sectional view showing details of the bimetal of another embodiment. The outer wall of the joint is provided with a low temperature constant treatment surface 38 which is treated so that the surface temperature becomes constant at low temperature, and a high temperature constant treatment surface 39 which is treated so as to be constant at high temperature. Further, there are protrusions 17a and 17b on the inner surfaces of the surface-treated portions 38 and 39, and bimetals 15 having the same structure and the same size are arranged between the protrusions and the mechanical element portions, respectively. To conduct heat. As the above-mentioned surface treatment parts 38 and 39, when this drive mechanism is used in outer space, white paint is applied as a surface treatment method that keeps the temperature low, and aluminum is used as a surface treatment method that keeps the temperature high. Vapor deposition is suitable. With this configuration, when the mechanical element portion exceeds the upper limit of the target temperature range, the left bimetal 15 is deformed to the left and the protrusion 17a is formed.
To contact. As a result, the heat is conducted through the bimetal 15 and is transferred from the mechanical element portion to the processing portion 38 which is surface-treated so as to be constant at a low temperature, and is radiated to outer space to lower the temperature of the mechanical element portion. When the temperature of the mechanical element portion falls below the lower limit of the target temperature range, the right bimetal 15 is deformed to the right and comes into contact with the protrusion 17b. As a result, heat is conducted through the right bimetal 15 from the surface treatment portion 39, which is treated to be constant at high temperature, and flows into the mechanical element portion to raise the temperature of the element portion. That is, according to the present embodiment, the temperature of the mechanical element part left in vacuum can be set within a certain target temperature range, and as a result, the temperature change of the element part can be reduced and a highly reliable drive mechanism can be realized. be able to.

According to the present invention, unnecessary radiant heat that invades is reflected by the outer wall of the driving means and the driving means is fixed to the outer wall of the driving means via a heat insulating material, so that the amount of heat entering from the outside becomes extremely small. Since the temperature change of the outer wall of the means becomes small, the gap between the outer wall of the driving means and the driven body can be made small, and the positioning accuracy becomes high. Further, by reducing the surface pressure of the contact portion between the outer wall of the driving means and the driven body, which is caused by the deformation due to the temperature change, to the allowable value or less, damage or wear of the contact surface can be prevented and the device can be used for a long time. By providing a means for controlling heat transfer between the drive means and the drive means outer wall, the temperature of the drive means outer wall inside the drive mechanism element is maintained at a predetermined value, and each element that constitutes the drive mechanism element. The temperature change between them can be reduced.

Front Page Continuation (72) Inventor Naoya Ezawa 4-6, Surugadai Kanda, Chiyoda-ku, Tokyo Hitachi, Ltd.

Claims (10)

[Claims] 1. A driving means for driving by connecting to a driven body under an environment of receiving radiant heat, and one of which is slidably connected to the driven body and the other is fixed to an extension body and comprises a heat reflecting material. A drive mechanism element comprising a drive means outer wall and a drive means fixing member made of a heat insulating material for fixing the drive means to the drive means outer wall. 2. A driving means for driving by connecting to a driven body under a vacuum environment receiving radiant heat, and one of which is slidably connected to the driven body and the other is fixed to an extension body from a heat reflecting material. A drive mechanism element comprising: an outer wall of the driving means, and a fixing means of the driving means made of a heat insulating material for fixing the driving means to the outer wall of the driving means. 3. The driving means fixing member is an FRP having a heat insulating property.
The drive mechanism element described in 1. 4. The drive mechanism element according to claim 3, wherein the FRP has a dual cone structure. 5. The driving means, a reduction gear having an input shaft engaged with one shaft of the motor and an output shaft connected to the driven body, and a braking provided on the other extension shaft of the motor. 2. A mechanism and a rotation sensor are provided.
Alternatively, the drive mechanism element according to claim 2. 6. The outer wall of the drive means is composed of a member made of a small-diameter rod-shaped material and responsible for the structural strength, and a heat shield plate surrounding the outer periphery of the member responsible for the structural strength. A drive mechanism element according to any one of claims 5. 7. A temperature sensor for detecting the temperature of the drive means and the outer wall of the drive means, and a temperature control means for controlling the temperature of the drive means and the outer wall of the drive means by a detection signal of the temperature sensor. A drive mechanism element according to claim 1 or claim 2 characterized. 8. The temperature control means includes a Peltier element for thermally connecting the driving means and the outer wall of the driving means, a power supply for supplying a current to the Peltier element, and a detection signal of the temperature sensor for the Peltier element. The drive mechanism element according to claim 7, further comprising a switcher that switches the direction of the current supplied to the element. 9. A surface treatment section in which a part of the outer wall of the driving means is subjected to surface treatment so as to be at room temperature, and a bimetal is arranged between the surface treatment section and the driving means. The drive mechanism element according to any one of claims 1 to 6. 10. A high-temperature surface-treated part in which a part of the outer wall of the driving means is surface-treated so as to have a high temperature, and a first bimetal arranged between the high-temperature surface-treated part and the driving means. 7. A low-temperature surface-treated part that has been surface-treated so as to have a low temperature, and a second bimetal arranged between the low-temperature surface-treated part and the driving means. A drive mechanism element according to any of the preceding claims.