JPH11247957A - Rack and pinion drive mechanism in vacuum processing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rack and pinion drive mechanism for moving a substrate tray, which can prevent tooth tips of a rack and a pinion from bumping upon each other with a simple structure so as to allow the rack and the pinion to smoothly mesh with each other. SOLUTION: A rack and pinion drive mechanism comprises a rack 11 fixed to a substrate they 13, a pinion 12 rotatably coupled to a power transmission mechanism, for meshing the rack and pinion so as to feed the tray by the rotary motion of the pinion, a position adjusting plate 22 provided to a pinion shaft and having a circular part formed therein with a plurality of protrusive parts having a synchronized relation with the phase of the teeth of the pinion, a magnet 23 for stopping the position adjusting plate at a predetermined position, a clutch mechanism 31 for engaging and disengaging between the power transmission mechanism and the pinion shaft, and a rack detector 33 for setting the clutch mechanism in an engaging mode or a disengaging mode.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rack and pinion drive mechanism for a vacuum processing apparatus, and more particularly to a rack and pinion drive mechanism used for a substrate tray transfer mechanism in a vacuum processing apparatus such as an in-line sputtering apparatus.

[0002]

2. Description of the Related Art In a vacuum processing apparatus for processing a substrate, a tray (substrate tray) on which a substrate is loaded or supported is transported into a processing chamber to perform desired processing on the substrate. When the vacuum processing apparatus is an in-line type, a plurality of processing chambers are connected in series, the substrate tray is transported sequentially through the processing chambers, and the processing of the moving substrate is sequentially performed in each processing chamber. Done.
When a rack and pinion mechanism is used as a drive mechanism of the substrate tray transport mechanism in such an in-line type vacuum processing apparatus, the rack is fixed to the substrate tray, a pinion is provided in each processing chamber, and the rack is engaged with the pinion in each processing chamber. The substrate tray is conveyed by rotating the pinion. The pinion is connected to the motor via a power transmission mechanism so as to be able to transmit power, and rotates when the rack and the pinion are engaged.

In the above case, when a substrate tray is carried into a certain processing chamber, a rack which is away from a pinion of the processing chamber approaches the non-rotating pinion and engages with the pinion. Collisions often occur. If a tooth tip collision occurs, the rack and pinion drive mechanism may be damaged, or in the worst case,
Further, the collision at the time of returning to normal engagement may cause damage to the substrate or substrate failure due to dust generation.

Conventionally, in order to solve the above-mentioned problem, a rack and pinion driving mechanism has been proposed, for example, in Japanese Patent Application Laid-Open No. Hei 8-74761. In this rack and pinion drive mechanism, the stop angle of the pinion shaft is set at a predetermined position by supporting the spherical member with a spring, pressing the spherical member against the concave portion of the cam, and setting the pinion guide and the rack before the pinion and the rack mesh with each other. It is configured to match the phase with the guide. According to such a configuration, the rack and the pinion can be engaged without causing collision of the tooth tip.

[0005]

According to the above-described conventional rack and pinion drive mechanism, the stop position of the pinion can be controlled based on the relationship between the cam and the spherical member supported by the spring. In addition, there is an advantage that a tooth tip collision does not occur between the rack and the pinion. However, when the rotational driving force is transmitted at a high speed with respect to the rotation of the pinion, the rotation stop angle accuracy is restricted by the mechanical structure, and the pinion cannot always be stopped at a fixed position. This causes a problem that the adjustment of the mechanical structure must be constantly repeated.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems. In a rack and pinion drive mechanism used for a substrate tray transfer mechanism, a collision between a rack and a pinion tooth tip can be avoided with a simple configuration. An object of the present invention is to provide a rack and pinion drive mechanism of a vacuum processing apparatus which can realize smooth engagement between a rack and a pinion and is easy to maintain.

[0007]

The rack and pinion drive mechanism of the vacuum processing apparatus according to the present invention is configured as follows to achieve the above object. The first rack and pinion drive mechanism (corresponding to claim 1) includes a rack fixed to a substrate tray, and a pinion connected to a power transmission mechanism and rotatably provided in a vacuum processing chamber. The pinion is engaged so that the substrate tray is conveyed by the rotation of the pinion. The pinion is further provided on a shaft member (pinion shaft) for fixing the pinion, and is made of a disk-shaped magnetic material. A position adjusting plate having a plurality of convex portions having a synchronous relationship with the circumferential portion, and a magnetic pole disposed near the position adjusting plate, opposed to the convex portion formed on the position adjusting plate, and having a position adjusting plate. , A clutch that couples and separates the power transmission mechanism and the shaft member, and a rack detector that sets the clutch to a coupling operation or a separation operation. In the rack and pinion drive mechanism, a position adjustment plate that maintains a synchronous relationship with the pinion attached to the other end of the shaft member of the pinion, and a magnet that determines a stop position of the position adjustment plate are provided. Is set at a position where the engagement of the racks is performed smoothly. The power transmission mechanism that transmits the rotational force to the shaft member of the pinion is set to a connected state or a separated state by a clutch. The operation of the clutch is performed based on the detection signal of the rack detector. It is preferable that the number and positions of the plurality of convex portions formed on the circumferential portion of the position adjusting plate are substantially the same as those of the plurality of teeth of the pinion. In the second rack and pinion drive mechanism (corresponding to claim 2), in the first configuration, a portion of a shaft member passing through a wall of the vacuum processing chamber is supported by a rotation introducing mechanism. Since the pinion is provided in the vacuum processing chamber and the position adjusting plate is provided outside the vacuum processing chamber, the shaft member passes through the wall of the vacuum processing chamber.
Therefore, a rotation introducing mechanism is provided to maintain the airtightness (vacuum state) of the vacuum processing chamber. The third rack and pinion drive mechanism (corresponding to claim 3) is the above-mentioned second configuration, wherein the rotation introducing mechanism is a seal mechanism using a magnetic fluid, and a magnetic shielding plate is provided between the seal mechanism and the magnet. Are arranged. Since the rotation introducing mechanism is constituted by a device using a magnetic fluid, the magnetic force shielding plate is arranged so that the magnetic force lines generated from the magnet do not affect the rotation. A fourth rack and pinion drive mechanism (corresponding to claim 4) is characterized in that, in the first configuration, the pedestal on which the magnet is mounted is provided with a position adjustment mechanism for changing the position of the magnet.
The position of the magnet determines the rotation stop position of the pinion via the position adjustment plate. In order to be able to adjust the rotation stop position, a position adjusting mechanism is provided. A fifth rack and pinion drive mechanism (corresponding to claim 5) is characterized in that, in the first configuration, a projection having a spherical tip portion is provided at the leading position of the tooth row of the rack. When the tip of the rack first engages with the pinion, the spherical projections and the teeth of the pinion are brought into contact with each other to prevent a locked state from occurring and to provide a smooth mesh. Sixth
The pinion drive mechanism (corresponding to claim 6) is provided with an idler gear meshing with the pinion, meshing the idler gear with the rack, and tilting the tip of each tooth of the idler gear in the width direction. It is characterized by having. By making the teeth of the idler gear beveled, smoother meshing is achieved.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings.

FIG. 1 shows a first embodiment of a rack and pinion drive mechanism according to the present invention, and FIG. 2 is a longitudinal sectional view of the rack and pinion drive mechanism. In the figure, 11 is a rack and 12 is a pinion. The rack 11 is fixed to the upper part of the substrate tray 13 set in the vertical direction along the upper part. The rack 11 has an elongated shape, and has a plurality of teeth on a side surface. In FIG. 1, both the rack 11 and the substrate tray 13 are partially shown on the front side.
It is assumed that the rack 11 and the substrate tray 13 move in a direction indicated by an arrow 14. Initially, the rack 11 and the pinion 12 are not engaged with each other, and when the rack 11 moves in the direction of the arrow 14, the rack 11 and the pinion 12 are engaged. In the illustrated state, the engagement of the rack 11 and the pinion 12 has been completed, and the two are maintained in an engaged relationship.

A substrate 15 to be processed is attached to one surface of the substrate tray 13. The substrate tray 13 is a member for transferring the substrate 15 to the vacuum processing chamber. Therefore, the illustrated substrate tray 13 exists inside the vacuum processing chamber. In FIG. 2, reference numeral 16 denotes a part of the wall of the vacuum processing chamber. In FIG. 1, the illustration of the wall portion 16 of the vacuum processing chamber is omitted. The lower side of the wall portion 16 is in a vacuum, and the upper side is in an atmospheric state. The pinion 12 is arranged inside the vacuum processing chamber. In practice, the substrate tray 13 is supported by a guide member (not shown), and moves while being guided by the guide member. The pinion 12 transmits power to the rack 11 based on the meshing relationship with the rack 11, thereby moving the substrate tray 13 in the direction of the arrow 14.

The pinion 12 is fixed to a lower end of a pinion shaft 17. As shown in FIG. 2, the pinion shaft 17 is attached to a shaft support member 18 fixed to a wall 16 of the vacuum processing chamber and a rotation introducing mechanism 19. The lower portion of the shaft support member 18 is disposed so as to penetrate through a hole 16a formed in the wall 16 of the vacuum processing chamber. The shaft support member 18 and the rotation introducing mechanism 19 are arranged so that their respective axes coincide with each other, and the rotation introduction mechanism 19 is further mounted on the shaft support member 18 fixed to the wall portion 16 of the vacuum processing chamber with bolts or the like. Etc. are fixed. The pinion shaft 17 includes a cylindrical shaft support member 18 and a rotation introducing mechanism 19 attached as described above.
Inserted into and supported by The rotation introducing mechanism 19 includes a seal portion using a magnetic fluid 20 therein, and maintains the vacuum of the vacuum processing chamber. The configuration of the seal portion of the rotation introducing mechanism 19 is not limited to this. The pinion shaft 17 inserted into the shaft support member 18 and the rotation introducing mechanism 19 has a plurality of ball bearings 2 as a mechanical structure.
1 supported. The upper part of the pinion shaft 17
The position adjusting plate 22 extends further upward from the rotation introducing mechanism 19 and is fixed to an upper end thereof. The position adjusting plate 22 has a plurality of convex portions 22a formed on a circumferential portion thereof. The position adjustment plate 22 is made of a magnetic material and is a disk-shaped member. The number of projections 22a is preferably the same as the number of teeth of pinion 12, and they are arranged so that they have the same phase. The phases of the projections 22a of the position adjusting plate 22 and the teeth of the pinion 12 only need to have a synchronous relationship, and the number of projections 22a is arbitrary.

A magnet (permanent magnet, electromagnet, or the like) 23 having the same height as the position adjusting plate 22 and a size corresponding to the size of the convex portion 22a is arranged. The magnetic pole at one end of the magnet 23 faces the tip of the projection 22 a of the position adjustment plate 22. The magnet 23 is supported by a support 25 erected on a support plate 24 fixed to the rotation introducing mechanism 19.
Is fixed on top. A slit 26 for position adjustment is formed in the support plate 24, and the magnet 2 is
3 can be changed. A magnetic shielding plate 28 is provided between the position adjusting plate 22 and the rotation introducing mechanism 19 so as to reduce the influence of the magnetic field on the magnetic fluid in the rotation introducing mechanism 19 to a level that does not pose a practical problem. This magnetic shielding plate 28 is preferably arranged below the clutch mechanism 31 described below.

The power transmission mechanism for transmitting the rotational driving force to the pinion shaft 17 includes a belt 29, a gear 30, and a clutch mechanism 31. The belt 29 is rotated by a motor (not shown) as indicated by an arrow 32 to rotate the gear 30. The gear 30 is arranged coaxially with the pinion shaft 17. As shown in FIG. 2, the clutch mechanism 31 is fixed to the upper end of the rotation introducing mechanism 19, and is disposed coaxially with the pinion shaft 17. An electromagnet 31a is built in the clutch mechanism 31, and when the electromagnet is excited, the clutch plate 31b is connected to transmit the rotational driving force of the belt 29 to the pinion shaft 17, and when the excitation of the electromagnet is released. , The clutch plate 31b is separated and the pinion shaft 1
The rotation of 7 stops. When the rotation of the pinion shaft 17 stops, the rotation stop position of the pinion shaft 17 is determined by the position adjustment plate 22.
Is determined based on the positional relationship between the and the magnet 23. Excitation operation (coupling operation) of the electromagnet 31a in the clutch mechanism 31
The non-excitation operation (separation operation) is performed based on a detection signal 34 of a rack detector 33 that detects whether the rack 11 has arrived. The rack detector 33 is disposed, for example, inside the vacuum processing chamber, and optically detects the presence of the rack. When the rack detector 33 does not detect the rack 11, the rack 11 and the pinion 12 are not engaged with each other, so that the clutch mechanism 31 is maintained in the separating operation state and the pinion 12 is stopped at a predetermined position. When the rack detector 33 detects the rack 11, the rack 11 and the pinion 12 are in a state where the engagement has been completed as shown in FIG. 1, so that the clutch mechanism 31 is maintained in the coupling operation state,
The rotation of the pinion 12 is started by transmitting the rotation driving force.
When the pinion 12 rotates, the rack 11
That is, the substrate tray 13 is transported in the direction of the arrow 14.

In FIG. 1, reference numeral 11a denotes a tip of the rack 11. A rack guide 35 is provided on the side surface of the distal end portion 11a of the rack 11 at the head of the row of teeth (teeth row). The rack guide 35 has a protruding shape, and its tip has a spherical shape. The distance between the rack teeth of the rack guide 35 is
It is the same as the interval between the rows of teeth in the rack 11. The rack guide 35 is a mechanism for smoothly engaging the rack 11 and the pinion 12 in the initial stage.

Next, the operation of the rack and pinion drive mechanism having the above configuration will be described. When the belt 29 is rotating by the operation of a motor (not shown), the belt 29
Is transmitted to the gear 30. Before the rack 11 meshes with the pinion 12, the clutch mechanism 3
Reference numeral 1 denotes a separating operation state, in which no rotational driving force is transmitted to the pinion shaft 17, and the pinion 12 is in a stopped state. When the clutch mechanism 31 is in the disengagement operation state, the tip of one of the protrusions 22 a provided on the circumferential portion of the position adjusting plate 22 is always shortest to the magnet 23 by the magnetizing force of the magnet 23. The pinion shaft 17 stops rotating and stands still so as to be located at a distance. That is, as long as the position adjusting plate 22 does not receive the rotational driving force from the belt 29, the distance between the tip of the convex portion 22a of the position adjusting plate 22 and the magnet 23 is kept at the shortest distance.

The stop position of the pinion shaft 17 based on the relationship between the position adjusting plate 22 and the magnet 23 is determined in advance according to the synchronous relationship between the phase of the projection 22a of the position adjusting plate 22 and the phase of the teeth of the pinion 12. Is set at a position where the tip of the pinion 12 does not collide with the incoming rack 11. Thus, the position adjustment plate 2
The pinion stop mechanism including the magnet 2 and the magnet 23
Before the pinion 12 engages with the pinion 12,
Is stopped at a predetermined rotation angle position. This rotational angular position is an angular position where the tooth guide collision with the meshing start portion of the pinion 12 does not occur when the rack guide 35 advances toward the pinion 12. In addition, the pinion 12
In order to optimally adjust the above-mentioned predetermined rotational angle position, the arrangement position of the magnet 23 can be changed by the screw type adjuster 27.

When the pinion 12 is stopped at the predetermined rotation angle position, the rack 11 is transported. The stop angle position of the pinion 12 is such that when the board tray 13 and the rack 11 move in the direction of the arrow 14, and as a result, the rack guide 35 advances toward the pinion 12,
Since the rack guide 35 and the pinion 12 are at an angular position that does not cause a tooth tip collision with the meshing start portion, the rack guide 35 and the pinion 12 mesh without causing a tooth tip collision. At this time, the phase of the teeth of the rack 11 and the pinion 1
The phases of the two teeth are synchronized. As the rack guide 35 further advances, the teeth of the rack 11 and the teeth of the pinion 12 in phase synchronization are shifted to a smooth meshing state. Since the tip of the rack guide 35 has a spherical shape, the rack and the pinion mesh smoothly.

The rack 11 moves forward and the rack detector 33
Detects the rack 11, the clutch mechanism 31 performs the coupling operation and transmits the rotational driving force to the pinion shaft 17. As a result, a rotational driving force exceeding the magnetic force based on the magnet 23 is applied to the pinion shaft 17 and the position adjusting plate 22, and the pinion 12 starts rotating, and the rack 11 and the substrate tray 13
Is continuously transported in the direction of arrow 14. When the transport of the rack 11 or the like is completed, the clutch mechanism 31 is again brought into the separating operation state, and the pinion 12 is stopped at the predetermined rotation angle position.

Next, a second embodiment of the present invention will be described with reference to FIGS. FIG. 3 is the same as FIG.
FIG. 4 is an enlarged sectional view showing a main part (idler gear) in FIG. 3. The present embodiment is characterized in that the intermediate gear 36 meshes with the pinion 12, the intermediate gear 36 and the idler gear 37 are fixed to the same shaft, and the idler gear 37 is meshed with the rack 11. . Other configurations are substantially the same as those of the above-described first embodiment, and a description thereof will be omitted. In FIG. 3, illustration of a substrate tray, a rack detector, and the like is omitted. As shown in FIG. 4, the idler gear 37 is formed so that at least a part of its tooth tip is inclined in the width direction. Providing the inclination 37a as described above has an advantage that the meshing can be performed more smoothly when the rack guide 11 meshes with the teeth of the idler gear 37.

[0021]

As is apparent from the above description, according to the present invention, in a transfer device of a vacuum processing apparatus using a rack and pinion drive mechanism, a pinion is rotated by a pinion stop mechanism including a position adjusting plate and a magnet by a predetermined rotation. Since the rack and the pinion are stopped at the angular position, a collision between the rack and the pinion tooth tip can be avoided with a simple configuration, a smooth engagement between the rack and the pinion can be realized, and maintenance can be easily performed.

[Brief description of the drawings]

FIG. 1 is a perspective view of a main part showing a first embodiment of the present invention.

FIG. 2 is a longitudinal sectional view of a main part of the first embodiment.

FIG. 3 is a perspective view of a main part showing a second embodiment of the present invention.

FIG. 4 is a sectional view of an idle gear.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Rack 12 Pinion 13 Substrate tray 16 Wall part 17 Pinion shaft 19 Rotation introduction mechanism 22 Position adjustment plate 22a Convex part 23 Magnet 28 Magnetic shielding plate 29 Belt 30 Gear 31 Clutch mechanism 32 Rack detector 35 Rack guide 36 Intermediate gear 37 Idler gear 37a Inclination

Claims (6)

[Claims] 1. A rack fixed to a substrate tray and a pinion connected to a power transmission mechanism and rotatably provided in a vacuum processing chamber, wherein the rack and the pinion are engaged with each other to rotate the substrate by a rotation operation of the pinion. In a rack and pinion drive mechanism of a vacuum processing apparatus that conveys a tray, a plurality of protrusions are provided on a shaft member that fixes the pinion, are made of a disk-shaped magnetic material, and have a synchronous relationship with the phase of the teeth of the pinion. A position adjusting plate provided with a portion on a circumferential portion, a magnetic pole disposed near the position adjusting plate, facing the convex portion formed on the position adjusting plate, and positioning the position adjusting plate at a predetermined position. A magnet for stopping, a clutch for coupling and disconnection between the power transmission mechanism and the shaft member, and a rack detector for setting the clutch to a coupling operation or a separation operation. Rack and pinion drive mechanism of the vacuum processing apparatus characterized by. 2. A rack and pinion drive mechanism for a vacuum processing apparatus according to claim 1, wherein a portion of said shaft member passing through a wall of said vacuum processing chamber is supported by a rotation introducing mechanism. 3. The vacuum processing apparatus according to claim 2, wherein the rotation introducing mechanism is a sealing mechanism using a magnetic fluid, and a magnetic shielding plate is disposed between the sealing mechanism and the magnet. Rack and pinion drive mechanism. 4. The rack and pinion drive mechanism for a vacuum processing apparatus according to claim 1, wherein the pedestal for mounting the magnet includes a position adjusting mechanism for changing a position of the magnet. 5. The rack according to claim 1, wherein a projection having a spherical tip is provided at a leading position of the tooth row of the rack.
A rack and pinion drive mechanism of the vacuum processing apparatus according to the above. 6. An idler gear meshing with the pinion is provided, the idler gear meshes with the rack, and the tip of each tooth of the idler gear is inclined in the width direction. 2. A rack and pinion drive mechanism for a vacuum processing apparatus according to claim 1.