JP4712888B2 - Positioning device - Google Patents

Description

  The present invention relates to a positioning device that positions an object on which positioning protrusions are formed.

  In recent years, MOCVD apparatuses have been developed as apparatuses for manufacturing compound semiconductors such as semiconductor laser elements and LED (Light Emitting Diode) elements (see, for example, cited references 1 and 2). An example of such an MOCVD apparatus will be briefly described below.

  FIG. 10 is a side sectional view showing an MOCVD apparatus (film forming apparatus). As shown in FIG. 10, in the MOCVD apparatus 1, a rotating shaft 6 that is rotated by a motor 7 is disposed inside the reaction chamber 2, and a rotating table 4 is supported on the upper end of the rotating shaft 6. In addition, a plurality of mounting tables 5 are provided on the upper surface of the rotating table 4, and these mounting tables 5 are configured to rotate by a rotation gear 8 and a fixed gear 9, respectively.

  FIG. 12 is a plan view showing the relationship between the turntable and the mounting table. As shown in FIG. 12, several (eight in this example) substrates 3 are placed on the mounting table 5. Examples of the material of the substrate 3 include Si, GaAs, GaN, and sapphire glass, and an appropriate material is used depending on the type of element to be produced. The substrate 3 placed on the mounting table 5 rotates and revolves due to the rotation of the rotating table 4 and the rotation of the mounting table 5. The uniformity of the crystal growth layer is improved by the mechanism in which the substrate 3 rotates and revolves.

  A heater 10 for heating the substrate 3 is disposed below the turntable 4, and information on the turntable 4 is provided with substantially parallel partitions 11 that separate the internal space of the reaction chamber 2.

  In addition, a gas outlet 13 of the pipe 12 connected to the gas supply unit 15 is disposed at the upper part of the reaction chamber 2. The raw material gas 14 which is the raw material of the crystal film is supplied radially from the rotating shaft of the rotating table 4 along the surface of the rotating table 4 through the gas outlet 13, and on the substrate 3 placed on the mounting table 5. Pass through. As a result, a desired chemical reaction is performed in the vicinity of the substrate 3, and a desired film forming process is performed on the substrate 3. The raw material gas 14 after passing over the substrate 3 is exhausted from an exhaust path 16 provided on the outer periphery of the turntable 4.

  Here, between the plurality of mounting tables 5 on the rotating table 4, the product is prevented from adhering to the rotating table 4 during the film forming process, and the upper surface of the substrate 3 is aligned with the surface of the substrate. In order not to disturb the flow of the raw material gas 14 passing therethrough, a plurality of (in this example, eight) turntable covers 17 are arranged. A schematic shape of the turntable cover 17 is shown in FIG.

  The turntable cover 17 is a quartz plate, and a pair of positioning pins 18 projecting from the lower surface of the turntable cover 17 are engaged with holes (not shown) provided on the upper surface of the turntable 4. The position is fixed to the turntable 4 so as not to be displaced.

  In the MOCVD apparatus as described above, naturally, the substrate must be set inside the apparatus prior to the film forming process. In addition, after the film formation process, the product formed by the film formation process adheres not only to the substrate but also to the surface of the turntable cover. Therefore, it is necessary to replace the turntable cover. In particular, when replacing the turntable cover, it is necessary to fit the positioning pins into the holes on the top surface of the turntable as described above, so the turntable cover must be accurately positioned.

  These operations are usually performed manually, but the substrate and the turntable cover are made of fragile materials such as sapphire and quartz, and the workers are required to be highly skilled and work carefully. Because it has to do, work takes time. For this reason, it has long been desired to automate these operations.

  Therefore, in order to automate the above-described work, it is considered necessary to arrange a positioning device in the vicinity of the reaction chamber of the MOCVD apparatus.

  Citation 3 discloses a positioning device that positions a substrate using a pair of cylindrical positioning pins protruding from the substrate. In the positioning device disclosed in the cited document 3, each of the pair of positioning pins protruding from the substrate is pressed against the V-groove reference piece and the flat reference piece by the pressing piece, whereby the substrate is It is positioned.

Japanese Laid-Open Patent Publication No. 2002-17592 (published on June 21, 2002) Special table 2004-513243 public information (released on April 30, 2004) Publicity of Shinshin Sho 61-131245 (released August 16, 1986)

  The present inventors examined the coefficient of friction required for successful positioning in a device that positions a positioning pin between a V-groove and a flat surface as in Patent Document 3. The examination result will be described with reference to FIG.

In FIG. 14, the positioning pin 103 is gripped and positioned between the V-shaped groove 101 and the flat portion 102. The force applied to the contact between the positioning pin 103 and flat portion 102 and _{F 1,} the frictional force between .mu.F _1. The force applied to the contact point between the positioning pin 103 and the V-shaped grooves 101 and _{F 2,} the frictional force between .mu.F _2. Further, the angle between the slope of the V-shaped groove 101 and the direction perpendicular to the pressing direction of the V-shaped groove 101 is θ.

  In FIG. 14, the balance in the X direction is represented by the following equation (1), and the balance in the Y direction is represented by the following equation (2).

F ₁ = μF ₂ sin θ + F ₂ cos θ (1)
F ₂ sin θ = μF ₁ + μF ₂ cos θ (2)
Therefore, the friction coefficient (μ) necessary for maintaining the position of the positioning pin in the posture shown in FIG. 14 is expressed by the following equation (3).

μ = (√ (cos ² θ + sin ² θ) −cos θ) / sin θ (3)
In order to enable positioning in FIG. 14, the present inventors need that the friction coefficient between the V-shaped groove 101 and the positioning pin 103 be not more than the limit friction coefficient μ shown by the above equation (3). I thought there was.

  For example, it is assumed that the V-shaped groove 101 is made of metal and the positioning pin 103 is made of quartz. Further, it is assumed that the angle θ is 45 deg. At this time, according to the above equation (3), the limit friction coefficient μ that can be positioned is 0.414 or less.

  However, the friction coefficient between the dried metal and quartz is generally about 0.4 to 0.6. For this reason, when using the positioning apparatus of the cited document 3, positioning will fail with high probability under the above assumptions.

  If it is a normal device, it is possible to reduce the friction coefficient by applying lubricating oil or the like to the V-groove reference piece or the positioning pin, or using a lubricating resin such as PTFE for the V-groove reference piece. . However, the use of lubricating oil or the like is not permitted in a film forming apparatus that is extremely reluctant to enter foreign substances. In addition, the temperature of each part in the film forming apparatus after film formation may be several hundred degrees, and therefore, lubricating oil, lubricating oil or the like cannot be used.

  Also, the use of solid lubricants such as molybdenum disulfide and graphite contaminates the inside of the apparatus, making it difficult to use them.

  Even if lubricating means such as lubricating oil or solid lubricant can be used, the lubricating state of these lubricating means gradually deteriorates. For this reason. For stable positioning operation, maintenance such as periodic replenishment of lubricant is required, which takes time and cost.

  In order to increase the value of the limitable limit friction coefficient μ, the angle θ between the slope of the V-shaped groove 101 and the direction perpendicular to the pressing direction of the V-shaped groove 101 may be increased to 45 degrees or more. . However, in this case, since the opening angle of the V-shaped groove 101 is reduced, the position error range that can be positioned is narrowed, and the positioning pin 103 is caught in the V-shaped groove 101 and cannot be removed. Resulting in.

  Therefore, as in the cited document 3, the apparatus for positioning the positioning pin between the V groove and the plane cannot stably perform positioning, particularly positioning of the components of the film forming apparatus.

  Moreover, when using the positioning apparatus like the cited document 3, positioning cannot be performed even in an environment (high temperature environment and vacuum environment) where it is difficult to take other lubrication means.

  The present invention has been made in view of the above-described problems, and the object thereof is lubrication means even when the coefficient of friction between the positioning member of the positioning device and the positioning projection of the positioning object is high. It is an object of the present invention to provide a positioning device that can stably perform positioning without using a sensor.

A positioning apparatus according to the present invention is a positioning apparatus that positions an object in which a pair of protrusions are formed in a columnar shape in order to solve the above-described problem,
A pair of V-shaped groove structures capable of approaching and separating, each having a V-shaped groove in an opposing arrangement and receiving one of the pair of protrusions between the V-shaped grooves;
A pair of planar structures capable of approaching and separating, each having a planar portion in an arrangement opposite to each other, and receiving the other projection of the pair of projections between the planar portions;
Each of the pair of V-shaped groove structures and the pair of planar structures is characterized by being close to each other at each arbitrary position for positioning each of the pair of protrusions.

  The positioning device according to the present invention positions an object having a pair of protrusions by a pair of V-shaped groove structures and a pair of planar structures.

  In the above configuration, the pair of V-shaped groove structures can approach and separate from each other, and when the pair of V-shaped groove structures approach, the pair of V-shaped groove structures approach each other at an arbitrary position for positioning one protrusion. At this time, at least three of the inclined surfaces constituting the V-shaped groove in the pair of V-shaped groove structures are in contact with one protrusion. Thereby, one protrusion is positioned between the V-shaped grooves.

  On the other hand, the pair of planar structures can approach and separate from each other. When the pair of planar structures approach, the pair of planar structures approach each other at an arbitrary position for positioning one projection. At this time, at least one planar portion in the pair of planar structures is in contact with the other of the other protrusions. Thereby, the other protrusion is positioned between the flat portions.

  That is, in the positioning device according to the present invention, positioning is performed by the pair of V-shaped groove structures determining the position of the object and the pair of planar structures determining the posture of the object.

In the above structure, when the V-shaped groove structure for positioning one of the projections, the force applied to the contact between the positioning pin 103 and flat portion 102 and F _1, the frictional force between .mu.F _1. The force applied to the contact point between the positioning pin 103 and the V-shaped grooves 101 and _{F 2,} the frictional force between .mu.F _2. In addition, the angle between the inclined surface forming the V-shaped groove and the direction perpendicular to the approaching direction of the V-shaped groove structure is θ.

  At this time, the balance of force in the direction perpendicular to the approach direction of the V-shaped groove structure is expressed by the following equation (4), and the balance of force in the approach direction of the V-shaped groove structure is expressed by the following equation (5). ).

F ₁ sin θ + F ₂ sin θ = μF ₁ cos θ + μF ₂ cos θ (4)
F ₁ cos θ + μF ₁ sin θ = F ₂ cos θ + μF ₂ sin θ (5)
Therefore, in the above configuration, the friction coefficient (μ) necessary for maintaining the position of the positioning pin is expressed by the following equation (6). In order for the V-shaped groove structure to position one protrusion, if the friction coefficient between the V-shaped groove structure and one protrusion is equal to or less than the limit friction coefficient (μ) represented by the following equation (6): Good.

μ = sin θ / cos θ (6)
According to the above equation (6), if the angle θ is 45 °, the limiting friction coefficient μ is 1. Therefore, in this case, if the coefficient of friction between the V-shaped groove structure and one protrusion is 1 or less, positioning is performed stably.

  The critical friction coefficient μ determined in the above configuration is dramatically higher than the critical friction coefficient in the conventional positioning device described above. Therefore, according to the positioning device of the present invention, even when the friction coefficient between the positioning member of the positioning device and the positioning projection of the positioning object is high, the positioning can be stably performed without using the lubricating means. Can be done.

  In the positioning device according to the present invention, at least one of the pair of V-shaped groove structures and at least one of the pair of planar structures may be integrally formed.

  According to the above configuration, it is possible to simplify the drive system for bringing the pair of V-shaped groove structures and the pair of planar structures close to each other.

Furthermore, in the positioning device according to the present invention, when the pair of V-shaped groove structures and the pair of planar structures are close to each other at the arbitrary positions,
The distance between the flat portions facing each other is as follows: a slope that forms a V-shaped groove in one V-shaped groove structure, and a V-shaped groove in the other V-shaped groove structure that faces the slope. Of the two distances determined by the distance between the slopes, the distance is preferably longer than at least one distance.

    If a situation occurs in which one planar structure grips the other before the pair of V-shaped groove structures position one projection, the object is positioned by the V-shaped groove structure due to the frictional force. Will be restrained before.

  According to the above configuration, even if at least three of the inclined surfaces constituting the V-shaped groove in the pair of V-shaped groove structures are in contact with one protrusion, the planar portions in the one planar structure are The other projection is not gripped during this period. That is, during a period from when the pair of V-shaped groove structures starts to approach until the at least three inclined surfaces come into contact with one projection, at least one plane portion in the pair of planar structures is between the other projection. Has a gap. Therefore, since the above situation does not occur, the positioning operation by the pair of V-shaped groove structures is not hindered, and the object can be positioned stably.

  In the positioning device according to the present invention, at least one of the pair of V-shaped groove structures and at least one of the pair of planar structures may be configured independently of each other.

  According to the above configuration, the pair of V-shaped groove structures and the pair of planar structures can be approached independently, so that it is easy to approach them in a preferred order.

  Furthermore, in the positioning device according to the present invention, it is preferable that the pair of planar structures are close to each other at the arbitrary positioning position after the pair of V-shaped groove structures are close to each other at the arbitrary position.

  According to the above configuration, each planar portion in the pair of planar structures does not hinder the positioning operation by the pair of V-shaped groove structures, and can contact the other projection without a gap therebetween. Therefore, positioning errors due to the pair of planar structures are reduced.

  In the positioning device according to the present invention, it is preferable that the pair of protrusions is made of quartz, and at least a contact portion with the protrusion in the V-shaped structure is made of metal or ceramic.

  According to the above configuration, a positioning device that satisfies the friction coefficient for positioning and that is excellent in terms of wear resistance and heat resistance can be realized.

  According to the positioning device of the present invention, the V-shaped grooves can be arranged in opposition to each other, and one of the pair of protrusions can be received between the V-shaped grooves to be able to approach and separate. A pair of V-shaped groove structures and a pair of planes that can be separated from each other and that receive the other projection of the pair of projections between the plane portions. Therefore, positioning can be performed stably without using any lubrication means.

1 is a perspective view showing a positioning device according to Embodiment 1. FIG. 3 is a top view showing a state before positioning in the positioning device according to Embodiment 1. FIG. 3 is a top view showing a state after positioning in the positioning device according to Embodiment 1. FIG. It is a figure for demonstrating the dimension in a pair of block. It is a figure for demonstrating the limiting friction coefficient at the time of positioning a positioning pin between a pair of V-shaped groove structure. It is a perspective view which shows the positioning device which concerns on Embodiment 2 of this invention. FIG. 10 is a top view showing a state before positioning in the positioning device according to the second embodiment. FIG. 10 is a top view showing a state in the middle of positioning in the positioning device according to the second embodiment. FIG. 10 is a top view showing a state after positioning in the positioning device according to the second embodiment. It is side surface sectional drawing which shows an example of the film forming apparatus. It is a figure shown about the arrangement | positioning relationship of a film forming apparatus, a positioning device, and a conveying apparatus. It is a top view which shows the relationship between a turntable and a mounting base. It is a perspective view which shows a turntable cover. It is a figure for demonstrating the limiting friction coefficient at the time of positioning a positioning pin between V groove and a plane.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings.

  In addition, the following embodiment is illustrated in order to actualize the technique which concerns on this invention, and does not limit the technical scope of this invention. Further, the technical contents according to the present invention can be variously modified within the technical scope described in the claims. For example, the combinations and dimensions of the members specifically described in each embodiment are not limited to those illustrated, and may be different combinations and dimensions as long as no particular problem occurs.

Embodiment 1
The positioning device 20 according to the first embodiment will be described below.

  In the following description, a rotating table cover will be described as an object to be positioned by the positioning device 20, but the present invention is not limited to this, and is appropriately applied to a device for positioning a member provided with a pair of positioning pins. it can.

  Although the positioning device 20 is not limited, as shown in FIG. 11, the rotating table cover is disposed in the vicinity of the film forming device (MOCVD device or the like) 50, and the rotation transported by the transport device 40. A device for positioning the base cover.

  The rotary cover positioned by the positioning device 20 is held by the transfer hand 42 of the transfer device 40 while being positioned, moved by the transfer arm 41, and transferred into the reaction chamber of the film forming device 50. The transported rotation cover is further fitted with a positioning pin by a transport device 40 in a hole provided on the upper surface of the turntable of the film forming device 50.

  FIG. 1 is a perspective view schematically showing the positioning device 20. As shown in FIG. 1, the positioning device 20 includes a base plate 21 on which components are placed, a pair of blocks 22, a guide mechanism 23, a drive unit 24, and a turntable cover support unit 27.

  The turntable cover 17 positioned by the positioning device 20 is a quartz plate member having a thickness of 2 mm, and two positioning pins (projections) 18 having a diameter of 3 mm and a length of 6 mm are spaced by 100 mm. Projecting from the bottom. At the time of positioning, the turntable cover 17 is arranged so that the pair of positioning pins 18 is inserted between the pair of blocks 22 as indicated by the arrows in FIG. 1 and supported by the turntable cover support portion 27. The

  The shape of the positioning pin 18 may be a cylinder as shown in FIG.

  The pair of blocks 22 are moved by the drive unit 24 so as to approach or separate from each other along the guide mechanism 23. In the following description, as shown in FIG. 1, the movement direction in which the pair of blocks 22 approach or separate from each other is defined as the X-axis direction, and the direction perpendicular to the X-axis direction on the plane of the base plate 21. Is the Y-axis direction.

  The pair of blocks 22 are paired so that the V-shaped groove 30 is disposed so that the V-shaped grooves 30 face each other on the opening side, and the plane (plane portion) 31 faces each other in parallel. The planar structure 26 is provided. The positioning pins 18 are arranged one by one between the pair of V-shaped grooves in the pair of V-shaped groove structures 25 and between the pair of planes 31 in the pair of planar structures 26.

  The pair of V-shaped groove structures 25 and the pair of planar structures 26 are close to (closest to each other) at an arbitrary position for positioning each of the pair of positioning pins 18. The arbitrary position may be set as appropriate based on the size of the positioning pin 18 and the like.

  The pair of V-shaped groove structures 25 are configured to grip the positioning pins 18 when the pair of blocks 22 are closest to each other. The slope forming the V-shaped groove 30 in the pair of V-shaped groove structures 25 forms an angle (open angle). If this angle is too wide, positioning will be difficult unless the friction coefficient between the inclined surface and the positioning pin 18 is lower than a certain level. There is a risk that it will be stuck and will not come out. For this reason, in this embodiment, the opening angle of the V-shaped groove 30 in the pair of V-shaped groove structures 25 is 90 °.

  The pair of planar structures 26 are configured not to grip the positioning pins 18 when the pair of blocks 22 are closest to each other. That is, even when the pair of blocks 22 are closest to each other, at least one plane 31 in the pair of planar structures 26 is configured to have a gap between the positioning pins 18.

  As a material for the pair of blocks 22, stainless steel (SUS304) is used in consideration of heat resistance, wear resistance, and cost. However, the present invention is not limited to this, and it is preferable to use ceramic in consideration of only heat resistance and wear resistance.

  Note that not all of the pair of blocks 22 are made of SUS304 or ceramic, and at least a contact portion with the positioning pin 18 in the pair of V-shaped groove structures 25 is preferably made of metal or ceramic. .

  The guide mechanism 23 is not particularly limited as long as it is a guide for smoothly moving the pair of blocks 22 along the X-axis direction. For example, in the present embodiment, the guide mechanism 23 has a rail-like structure provided on the base plate 21, and the pair of blocks 22 are engaged with the guide mechanism 23 and moved.

  The drive unit 24 drives each block 22 such that the pair of blocks 22 approach or separate from each other. A conventional method may be used as the driving method, and is not particularly limited.

  The turntable cover support 27 is not particularly limited as long as it supports the turntable cover 17 from below during positioning. For example, in this embodiment, the turntable cover support portion 27 is configured by three columns provided on the base plate 21. Further, the height of the turntable cover support portion 27 is set higher than the height of the block 22 so that the lower surface of the turntable cover 17 does not contact the upper surface of the block 22 during positioning. As a result, only the positioning pins 18 of the turntable cover 17 come into contact with the pair of blocks 22.

  Next, the positioning operation of the positioning device 20 will be described with reference to FIGS. FIG. 2 is a top view showing a state before positioning in the positioning device 20 on which the turntable cover 17 is set. In FIG. 2, the plate-like portion of the turntable cover 17 is omitted for explanation.

  As shown in FIG. 2, first, the turntable cover 17 is set on the positioning device 20 in a state where the pair of blocks 22 are separated from each other. The setting is completed by placing the turntable cover 17 on the turntable cover support 27, and the setting position at this time is the positioning pin 18 between the pair of V-shaped groove structures 25 and the pair of planar structures 26. Any position may be used as long as each is placed one by one. FIG. 2 shows a state in which the positioning pin 18 is displaced from the position after positioning for the sake of explanation.

  After the setting, the driving unit 24 drives the pair of blocks 22 and the pair of blocks 22 moves so as to be close to each other. At the time of this movement, any one of the four inclined surfaces constituting the V-shaped groove in the pair of V-shaped groove structures 25 first comes into contact with the positioning pins 18 arranged between the pair of V-shaped groove structures 25. Alternatively, first, one of the two planes 31 in the pair of planar structures 26 contacts the positioning pin 18 disposed between the pair of planar structures 26. Thus, when any surface of the block 22 comes into contact with either one of the two positioning pins 18, the positioning pin 18 is pushed and moved by the surface of the contacting block 22, The other positioning pin 18 is also in contact with the other surface of the block 22.

  When the contact partner of the positioning pin 18 is one of the four inclined surfaces in the pair of V-shaped groove structures 25, the positioning pin 18 is pushed by the contacting inclined surface and moves in the X-axis direction and the Y-axis direction. On the other hand, when the contact partner of the positioning pin 18 is one of the two planes 31 in the pair of planar structures 26, the positioning pin 18 is pushed by the contacted plane 31 and moves only in the X-axis direction.

  Finally, the pair of V-shaped groove structures 25 moves the positioning pins 18 in the X-axis direction and the Y-axis direction, and among the four inclined surfaces constituting the V-shaped grooves in the pair of V-shaped groove structures 25 The positioning pin 18 is gripped by at least three inclined surfaces. Thereby, the pair of V-shaped groove structures 25 positions the positioning pins 18 at predetermined positions.

  On the other hand, the pair of planar structures 26 moves the positioning pin 18 only in the X-axis direction and positions the positioning pin 18 at a predetermined position by any one of the planes 31.

  That is, the pair of V-shaped groove structures 25 moves the positioning pins 18 in the X-axis direction and the Y-axis direction and positions them at predetermined positions, whereas the pair of planar structures 26 has a pair of V-shaped grooves. With the positioning pin 18 gripped by the structure 25 as a center of rotation, the rotation direction of the turntable cover 17 is positioned in a predetermined direction. In other words, the pair of V-shaped groove structures 25 determines the position of the turntable cover 17, and the pair of planar structures 26 determines the posture of the turntable cover 17.

  As described above, the rotary table cover 17 is positioned. FIG. 3 is a top view showing a state after positioning in the positioning device 20.

  Here, if the pair of planar structures 26 grips the positioning pins 18 before the pair of V-shaped groove structures 25 grips the positioning pins 18, both positioning pins 18 cannot move. Therefore, positioning by the pair of V-shaped groove structures 25 is hindered.

  Therefore, in this embodiment, the pair of planar structures 26 are configured not to grip the positioning pins 18 as described above.

  Specifically, as shown in FIG. 4, when the pair of blocks 22 are closest, the distance a between the planes 31 facing each other is one of the V-shaped grooves 30 of the pair of V-shaped grooves 30. It is longer than at least one distance among the distances b1 and b2 determined by the slope constituting the groove 30 and the slope constituting the other V-shaped groove 30 facing the slope. That is, when the pair of blocks 22 are closest, the four slopes constituting the pair of V-shaped grooves 30 are at least one distance b1 or b2 out of two distances determined between the slopes facing each other. This corresponds to the diameter of the positioning pin 18. On the other hand, when the pair of blocks 22 are closest, the distance a between the planes 31 facing each other is longer than the diameter of the positioning pin 18.

  Therefore, when the pair of blocks 22 comes closest, the pair of V-shaped groove structures 25 grips the positioning pins 18, but there is no gap between any of the flat surfaces 31 in the pair of planar structures 26 and the positioning pins 18. Exists.

  For this reason, the situation that positioning by a pair of V-shaped groove structure 25 is obstructed because a pair of plane structure 26 grasps positioning pin 18 does not occur in this embodiment. Therefore, the positioning device 20 according to this embodiment can stably position the positioning pin 18.

  After the positioning is completed, the positioning pin 18 may be opened by driving the pair of blocks 22 again by the driving unit 24 to separate them. Since the turntable cover 17 is supported by the turntable cover support portion 27, the turntable cover 17 does not move from the positioned position even if the pair of blocks 22 are separated.

  In FIG. 3, the gap between the plane 31 and the positioning pin 18 is emphasized for the sake of explanation, but in reality, the gap is such that the pair of planar structures 26 do not grip the positioning pin 18. If there is enough.

  Next, the friction coefficient between the pair of V-shaped groove structures 25 and the positioning pins 18 will be described with reference to FIG. FIG. 5 is an explanatory diagram for explaining how the V-shaped groove structure 25 positions the positioning pins 18. In FIG. 5, only a pair of V-shaped groove structures 25 are shown for explanation, and the pair of planar structures 26 and the like are omitted.

5, when a pair of V-shaped groove structure 25 positions the positioning pin 18, the force exerted on the contact point between one of the V-shaped grooves 30 and the positioning pins 18 and F _1, the frictional force between .mu.F ₁ To do. The force applied to the contact between the positioning pin 18 and the other one of the V-shaped grooves 30 and F _2, the frictional force between .mu.F _2. In addition, an angle between a slope constituting the V-shaped groove 30 in the pair of V-shaped groove structures 25 and a direction perpendicular to the approaching direction of the pair of V-shaped groove structures 25 is defined as θ.

  At this time, the balance of force in the direction perpendicular to the approach direction of the pair of V-shaped groove structures 25 is expressed by the following equation (7), and the balance of force in the approach direction of the V-shaped groove structure 25 is as follows. (8)

F ₁ sin θ + F ₂ sin θ = μF ₁ cos θ + μF ₂ cos θ (7)
F ₁ cos θ + μF ₁ sin θ = F ₂ cos θ + μF ₂ sin θ (8)
Therefore, in the above configuration, the friction coefficient (μ) necessary for maintaining the position of the positioning pin 18 is expressed by the following equation (9). In order for the V-shaped groove structure to position one protrusion, the friction coefficient between the pair of V-shaped groove structure 25 and the positioning pin 18 is equal to or less than the limit friction coefficient (μ) represented by the following equation (9). If it is.

μ = sin θ / cos θ (9)
In the present embodiment, the opening angle of the V-shaped groove 30 in the pair of V-shaped groove structures 25 is 90 °. Therefore, the angle θ is 45 °, and the limit friction coefficient μ for positioning is 1 according to the above equation (9). Therefore, if the coefficient of friction between the pair of V-shaped groove structures 25 and the positioning pins 18 is 1 or less, the positioning is sufficiently possible.

  In the present embodiment, the friction coefficient between the pair of V-shaped groove structures 25 and the pin 18 is a friction coefficient when SUS304 and quartz are not lubricated, and is approximately 0.4 to 0.6. Therefore, the friction coefficient between the pair of V-shaped groove structures 25 and the positioning pins 18 is sufficiently within the range of the limit friction coefficient μ for positioning. Therefore, the positioning device 20 according to the present embodiment can stably position the positioning pin 18 without using a lubricating means.

  Further, since the field friction coefficient μ in the present embodiment is greatly improved as compared with the conventional case, even if the friction coefficient between the positioning pin and the pair of V-shaped groove structures 25 is high, the lubrication means is used. Positioning can be performed stably without using it.

  Further, the opening angle of the V-shaped groove 30 in the pair of V-shaped groove structures 25 is not limited to 90 °, and may be larger or smaller than this.

  For example, when the opening angle of the V-shaped groove 30 in the pair of V-shaped groove structures 25 is increased, the position range that can be positioned is widened, and even if there is a large error in the mounting position of the turntable cover 17 There is an advantage that you can. However, the critical friction coefficient μ for positioning is small. Therefore, as described above, the coefficient of friction between the metal and quartz when not lubricated is approximately 0.4 to 0.6, and therefore the maximum opening angle of the V-shaped groove 30 in the pair of V-shaped groove structures 25. Is preferably 118 ° at which the limiting friction coefficient μ is 0.6.

  On the other hand, when the opening angle of the V-shaped groove 30 in the pair of V-shaped groove structures 25 is reduced, there is an advantage that the critical friction coefficient μ for positioning is increased. However, the position range in which positioning can be performed is narrowed, and there is a high possibility that the pin is caught in the V-shaped groove 30 and cannot be removed. Therefore, the minimum opening angle of the V-shaped groove 30 in the pair of V-shaped groove structures 25 is preferably about 60 °.

  From the above, it is preferable that the opening angle of the V-shaped groove 30 in the pair of V-shaped groove structures 25 is in a range of 60 ° to 118 °. Good.

  In the present embodiment, the drive unit 24 is provided independently for each of the pair of blocks 22, but the present invention is not limited to this, and the pair of blocks 22 may share the drive unit 24. One of the pair of blocks 22 may be fixed and only the other may be movable.

[Embodiment 2]
Another embodiment according to the present invention will be described below with reference to FIGS. In this embodiment, in order to explain the differences from the first embodiment, for the sake of convenience of explanation, members having the same functions as those described in the first embodiment are given the same member numbers, and The description may be omitted.

  FIG. 6 is a perspective view schematically showing the configuration of the positioning device 20a of the present embodiment. The positioning device 20a is a device for positioning the turntable cover 17 of the MOCVD apparatus, as in the first embodiment. In this embodiment, instead of the pair of blocks 22 of the first embodiment described above, a pair of V-shaped grooved blocks 28 and a pair of flat blocks 29 are provided as shown in FIG. In addition, the positioning device 20a includes a base plate 21 on which components are placed, a guide mechanism 23, a drive unit 24, and a turntable cover support unit 27.

  As shown by the arrows in FIG. 6, the turntable cover 17 is arranged so that the pair of positioning pins 18 enter between the pair of V-shaped groove structures 25 and the pair of planar structures 26, respectively. It is supported by the base cover support part 27.

  The pair of V-shaped grooved blocks 28 are moved by the drive unit 24 so as to approach or separate from each other along the guide mechanism 23. The pair of V-shaped grooved blocks 28 includes a pair of V-shaped groove structures 25 arranged so that the V-shaped grooves 30 face each other on the opening side.

  The pair of V-shaped groove structures 25 are configured to grip the positioning pins 18 when the pair of V-shaped grooved blocks 28 come closest to each other. The opening angle of the slope forming the V-shaped groove 30 in the pair of V-shaped groove structures 25 is 90 °, as in the first embodiment.

  The pair of planar blocks 29 are moved by the drive unit 24 so as to approach or separate from each other along the guide mechanism 23. The pair of planar blocks 29 includes a pair of planar structures 26 arranged so that the planes 31 face each other in parallel. Unlike the first embodiment, the pair of planar structures 26 are configured to grip the positioning pins 18 when the pair of planar blocks 29 are closest to each other.

  In this embodiment, SUS304 is used as the material of the V-shaped grooved block 28 and the flat block 29 in consideration of heat resistance, wear resistance, and cost. However, the present invention is not limited to this, and it is preferable to use ceramic in consideration of only heat resistance and wear resistance.

  The guide mechanism 23 is provided for each of the pair of V-shaped grooved blocks 28 and the pair of flat blocks 29 and is a guide for smoothly moving these blocks along the X-axis direction. There is no particular limitation.

  The drive unit 24 is provided for each of the pair of V-shaped grooved blocks 28 and the pair of flat blocks 29. The drive unit 24 drives each V-shaped grooved block 28 so that the pair of V-shaped grooved blocks 28 approach or separate from each other, and each of the pair of planar blocks 29 approaches or separates from each other. The flat block 29 is driven.

  The turntable cover support portion 27 is configured by three columns provided on the base plate 21 as in the first embodiment. The height of the turntable cover support 27 is set such that the lower surface of the turntable cover 17 does not come into contact with the upper surfaces of the V-shaped grooved block 28 and the flat block 29 during positioning. It is set higher than the height of the block 29. As a result, only the positioning pin 18 of the turntable cover 17 comes into contact with the V-shaped grooved block 28 and the flat block 29.

  Next, the positioning operation of the positioning device 20a will be described with reference to FIGS. FIG. 7 is a top view showing a state in which the turntable cover 17 is set on the positioning device 20. In FIG. 7, the plate-like portion of the turntable cover 17 is omitted for explanation.

  As shown in FIG. 7, the turntable cover 17 is first set on the positioning device 20a in a state where the pair of blocks 22 are separated from each other. The setting is completed by placing the turntable cover 17 on the turntable cover support stand 27. At this time, the positioning pins 18 are located between the pair of V-shaped groove structures 25 and the pair of planar structures 26. Any position may be used as long as it is arranged one by one. FIG. 7 shows a state in which the positioning pin 18 is displaced from the position after positioning for the sake of explanation.

  After setting, the drive unit 24 drives the pair of V-shaped grooved blocks 28, and the pair of V-shaped grooved blocks 28 moves so as to be close to each other. At the time of this movement, any one of the four inclined surfaces constituting the V-shaped groove in the pair of V-shaped groove structures 25 first comes into contact with the positioning pins 18 arranged between the pair of V-shaped groove structures 25. Subsequently, the positioning pin 18 is pushed by the inclined surface of the V-shaped groove 30 in the V-shaped groove structure 25 in contact, and moves in the X-axis direction and the Y-axis direction. When the pair of V-shaped grooved blocks 28 further approach, finally, as shown in FIG. 8, at least three of the four inclined surfaces constituting the V-shaped groove in the pair of V-shaped groove structures 25. To hold the positioning pin 18.

  Next, the driving unit 24 drives the pair of plane blocks 29, and the pair of plane blocks 29 moves so as to be close to each other. During this movement, first, one of the two planes 31 in the pair of planar structures 26 comes into contact with the positioning pin 18 that is not yet gripped. Next, the positioning pin 18 is pushed by the contacted flat surface 31 and rotates around the positioning pin 18 previously gripped by the pair of V-shaped groove structures 25. When the pair of planar blocks 29 further approach each other, finally, as shown in FIG. 9, the two planes 31 in the pair of planar structures 26 grip the positioning pins 18.

  That is, also in the present embodiment, the pair of V-shaped groove structures 25 are positioned at predetermined positions by moving the positioning pins 18 in the X-axis direction and the Y-axis direction, whereas the pair of planar structures 26 is a pair of With the positioning pin 18 gripped by the V-shaped groove structure 25 as a center of rotation, the rotation direction of the turntable cover 17 is positioned in a predetermined direction. In other words, the pair of V-shaped groove structures 25 determines the position of the turntable cover 17, and the pair of planar structures 26 determines the posture of the turntable cover 17.

  As described above, the positioning of the turntable cover 17 is completed. After the positioning is completed, the pair of V-shaped grooved blocks 28 and the pair of flat blocks 29 are separated from each other, and the positioning pins 18 are opened.

  In the present embodiment, since the positioning is performed using the pair of V-shaped groove structures 25 and the pair of planar structures 26 as in the first embodiment, the pair of V-shaped groove structures 25 and the positioning pins 18 Even if the friction coefficient is larger than that of the prior art, positioning can be performed stably. Therefore, the positioning device 20a according to the present embodiment can position the positioning pin 18 without using a lubricating means.

  In the present embodiment, the pair of planar structures 26 grips the positioning pins 18 after the pair of V-shaped groove structures 25 grips the positioning pins 18. For this reason, the situation that positioning by the pair of V-shaped groove structures 25 is hindered by the pair of planar structures 26 holding the positioning pins 18 first does not occur in this embodiment. Therefore, the positioning device 20a according to the present embodiment can stably position the positioning pin 18.

  In the present embodiment, since the pair of planar structures 26 grip the positioning pin 18 without a gap between them, the positioning error is small.

  The moving order of the V-shaped grooved block 28 and the flat block 29 is not limited to the above. For example, the order may be such that the pair of planar structures 26 are first approached to the positioning pins 18 and then the pair of V-shaped groove structures 25 are gripped by the positioning pins 18. At this time, it is preferable that the positioning pins 18 are not gripped by the pair of planar structures 26 so that the positioning pins 18 are not restrained by the planar structures 26.

  Further, in the present embodiment, the drive unit 24 is provided independently for each of the V-shaped grooved block 28 and the flat block 29, but the present invention is not limited to this. For example, the V-shaped grooved blocks 28 or the planar blocks 29 may be shared. Further, it may be configured such that either one of the pair of V-shaped grooved blocks 28 or the pair of flat blocks 29 is fixed and only the other is movable.

  The positioning device according to the present invention is preferably used as a device for positioning an object on which positioning protrusions are formed, particularly as a device for positioning a component of a film forming apparatus that cannot use a lubricating means. Can do.

17 Turntable cover 20, 20a Positioning device 22 Block 25 V-shaped groove structure 26 Planar structure 28 V-shaped grooved block 29 Planar block 30 V-shaped groove 31 Planar

Claims (5)

A positioning device for positioning an object having a pair of protrusions formed in a columnar shape,
A pair of V-shaped groove structures capable of approaching and separating, each having a V-shaped groove in an opposing arrangement and receiving one of the pair of protrusions between the V-shaped grooves;
A pair of planar structures capable of approaching and separating, each having a planar portion in an arrangement opposite to each other, and receiving the other projection of the pair of projections between the planar portions;
Each of the pair of V-shaped groove structures and the pair of planar structures is close to each other at each arbitrary position for positioning the pair of protrusions ,
When the pair of V-shaped groove structures are close to each other at the arbitrary position,
The distance between the flat portions facing each other is as follows: a slope that forms a V-shaped groove in one V-shaped groove structure, and a V-shaped groove in the other V-shaped groove structure that faces the slope. A positioning device characterized by being longer than at least one of two distances determined by the distance between the slopes .   The positioning device according to claim 1, wherein at least one of the pair of V-shaped groove structures and at least one of the pair of planar structures are integrally configured.   The positioning device according to claim 1, wherein at least one of the pair of V-shaped groove structures and at least one of the pair of planar structures are configured independently of each other. The positioning device according to claim 3 , wherein the pair of planar structures are close to each other at the arbitrary positioning position after the pair of V-shaped groove structures are close to each other at the arbitrary position. The pair of protrusions is made of quartz,
Positioning device for at least the contact portion between the projections according to any one of claims 1, characterized by being composed of metal or ceramic 4 in the V-shaped groove structure.

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