JPH0678655U - Rack and pinion meshing mechanism - Google Patents

Abstract

(57) [Summary] [Purpose] To make the initial meshing of the rack and pinion mechanism smooth and normal. [Constitution] In the rack and pinion mechanism, the pinion 1
Alternatively, at least the tooth 5 of the gear that rotates in synchronization is formed of a magnetic material, and the magnet 7 is arranged around the pinion 1. By appropriately adjusting the form, structure and arrangement position of the magnet 7, when the rotation of the pinion 1 stops, when the rack 2 and the pinion 1 next try to mesh with each other, the magnet 7 stops at a position where smooth initial meshing is possible. Achieve what you let. Even if the magnet 7 and the tooth 5 are made of different materials, the same effect is produced.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a rack and pinion meshing mechanism, and more particularly to a rack and pinion meshing mechanism applied to a rack and pinion feed mechanism used in a conveyor.

[0002]

[Prior art]

 For example, in a transfer apparatus that sequentially moves a carrier on which an object to be sputtered is placed in each processing chamber in a vacuum processing apparatus having a plurality of processing chambers, it is generally used as a mechanism for transmitting a driving force for moving the carrier. A feed mechanism that uses a rack and pinion mechanism is used for.

In a conventional rack and pinion mechanism, when a rack in a state separated from a pinion approaches and meshes with a pinion in a rotation stopped state, in order to avoid collision of both tooth tips, Methods such as using a directional clutch and releasing the pinion in a direction perpendicular to its axis are used. There is also a method in which a pin is pressed between the teeth when the rotation of the pinion is stopped by a pneumatic cylinder or an electromagnet so that the teeth of the pinion are always aligned in a certain direction so that the teeth of the pinion surely mesh with the rack.

[0004]

[Problems to be solved by the device]

 In the conventional avoidance means, the method using the one-way clutch has a drawback that the moving direction of the rack is limited to only one direction. In addition, the method of letting the pinion escape in a direction perpendicular to the axis requires a large space because it requires complicated intermediate mechanism and two intermediate gears to be arranged in a reciprocating structure. Further, the method using a pneumatic cylinder or the like has a drawback that it requires a pneumatic or electric power drive source and requires a large space for disposing these mechanisms.

An object of the present invention is to provide a rack and pinion meshing mechanism capable of smoothly meshing a rack and a pinion for the first time with a simple structure.

[0006]

[Means for Solving the Problems]

 A first rack and pinion meshing mechanism according to the present invention forms at least teeth of a pinion with a magnetic material, and when the rotation of the pinion is stopped, the pinion and the rack can be smoothly meshed at an initial position. Place a magnet to stop around the pinion.

In the second rack and pinion mechanism according to the present invention, at least the tooth portion of the gear that rotates in synchronization with the pinion is formed of a magnetic material, and the initial engagement between the pinion and the rack when the rotation of the pinion is stopped. Place a magnet around the gear to stop the pinion in a position that allows smooth movement.

In each of the above configurations, the configuration of the main part may be reversed, and the tooth portion may be formed of a magnetized member, and a magnetic body may be used instead of the magnet.

[0009]

[Action]

 According to the present invention, when there is another gear that rotates around the pinion or in synchronization with the pinion, the magnetic force lines of the magnets arranged at predetermined positions around the gear cause the pinion tooth stop position to move. Limited. The stop position of the pinion teeth, which is limited by the magnet, is the position where the first engagement is smooth or normal when the rack approaches the pinion and the rack engages the pinion. Similar effects can be produced when the configurations are reversed.

[0010]

【Example】

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

FIG. 1 shows the configuration of the main part of the present invention. In FIG. 1, 1 is a pinion rotatably supported around a rotary shaft 1a, and 2 is a rack which moves in the right direction 3, for example. , Its tip is shown. The position of the rotating shaft 1a of the pinion 1 is fixed. The rotation shaft 1a of the pinion 1 is connected to, for example, a rotation drive shaft of a drive device (not shown), and rotates in the counterclockwise direction 4 when rotational power is given from the drive device. When the pinion 1 receives the rotational force and rotates counterclockwise 4 while the rack 2 meshes with the pinion 1, the rack 2 moves rightward 3. The problem is whether the teeth 6 of the rack 2 moving in the right direction 3 and the teeth 5 of the pinion 1 are initially (first) meshed smoothly while avoiding collision between the teeth.

At least a portion of the tooth 5 of the pinion 1 is made of a magnetic material that allows magnetic force lines to pass therethrough. A magnet 7 is arranged at an appropriate position around the pinion 1 so as to be close to the pinion 1. The magnet 7 is preferably a permanent magnet and has two magnetic pole pieces 8a and 8b having a predetermined spacing. The magnetic pole pieces 8a, 8b are plate-shaped, and the distance between the magnetic pole pieces 8a, 8b is substantially equal to the distance between the tips of two adjacent teeth 5 of the pinion 1. The action of the magnet 7 is such that when the rotating pinion 1 is stopped, each of the two adjacent teeth 5 of the pinion 1, for example, is made to use the attraction action of the magnet 7 for the magnetic pole pieces 8a, 8b. It is to stop in the state corresponding to. In FIG. 1, the pinion 1 is stopped with the teeth 5a and 5b corresponding to the magnetic pole pieces 8a and 8b, respectively.

The position where the magnet 7 is arranged is determined by the position of the pinion 1 that meshes with the tooth 6a at the tip of the rack 2 when the teeth 5a, 5b of the pinion 1 and the pole pieces 8a, 8b shown in FIG. The teeth 5c and 5d are locations where smooth initial meshing is possible. As a result, the pinion 1 in the rotation stopped state waits at a position where it normally meshes with the teeth 6a at the tip of the rack 2, avoiding collision between the tooth tips and achieving smooth initial meshing.

The above embodiment can be modified as follows. The magnetic pole pieces 8a and 8b may be omitted and only the magnet 7 may be provided. Further, the magnet 7 can be made of an electromagnet instead of a permanent magnet. As a configuration opposite to that of the above-described embodiment, the same effect can be produced by magnetizing the teeth 5 of the pinion 1 and arranging a simple magnetic body having a similar shape instead of the magnet 7.

As another embodiment, when there is another gear that rotates in synchronization with the pinion 1, the above-mentioned embodiment is provided between the tooth portion of this gear and the magnet 7 arranged in the vicinity thereof. By providing a configuration similar to the example, the initial meshing between the pinion 1 and the rack 2 can be performed smoothly. Other gears that rotate in synchronization with the pinion 1 include, for example, a gear that meshes with the pinion 1 to rotate, a gear fixed to the rotating shaft 1a of the pinion 1, and the like.

FIG. 2 shows an example of an apparatus to which the rack and pinion meshing mechanism of each of the above embodiments is applied. This device is a transfer device that is applied to a vacuum processing device in which a plurality of processing vacuum chambers are connected in series and isolated from each other by a gate valve. This transfer device is a carrier on which a wafer to be processed is placed. Are sequentially sent to each vacuum chamber. In each vacuum chamber, necessary processing is performed on the loaded wafer. In FIG. 2, 31 is a vacuum processing apparatus, 11 is a section of the first vacuum chamber, 12 is a section of the second vacuum chamber, and 13 is a section of the third vacuum chamber.

In FIG. 2, 32 is two rails arranged in parallel, and 33 is the carrier having a rectangular planar shape. The wafer 34 is placed on the carrier 33. A guide member 9 is attached to the rail 32 and guides the carrier 33 in the moving direction. The carrier 33 is guided on the rail 32 by the guide member 9 and moves in the direction indicated by 10. The ten directions indicated by the arrows are forward directions.

The rack 2 is formed on the front side of the carrier 33. Further, among the two rails 32, a plurality of pinions 1 are provided at regular intervals along the front rail in FIG. The carrier 33 has its rack 2 sequentially meshed with each pinion 1, and the power is transmitted from each pinion 1 in the meshed state, whereby the carrier 33 moves in the direction of 10. At this time, in order to smoothly perform the initial meshing between the rack 2 and each pinion 1, the meshing mechanism described in FIG. 1 is provided. That is, the magnet 7 (not shown in FIG. 2) provided with, for example, the magnetic pole pieces 8a and 8b shown in FIG. 1 is arranged at an appropriate position on the circumference of the pinion 1.

[0019]

[Effect of device]

 As is clear from the above description, according to the present invention, the engaging position of the rotating pinion is always maintained so that the initial meshing of the rack and the pinion can be made smooth by utilizing the attracting action of the magnetic field of the magnet and the magnetic substance. It can be placed in a normal position, and a simple mechanism with a small number of parts ensures smooth meshing.In addition, reliability in driving force transmission is improved, manufacturing and maintenance are simplified, and driving force is improved. The transmission mechanism can be made compact and cost down can be achieved.

[Brief description of drawings]

FIG. 1 is a view showing a main configuration of a rack and pinion meshing mechanism according to the present invention.

FIG. 2 is a view showing an application example of the rack and pinion meshing mechanism according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 pinion 2 rack 5,5a-5d tooth of pinion 6,6a tooth of rack 7 magnet 8a, 8b pole piece

Claims (4)

[Scope of utility model registration request] 1. A mechanism in which a rack and a pinion mesh with each other, wherein at least a tooth portion of the pinion is made of a magnetic material, and when the rotation of the pinion is stopped, the pinion and the rack can be smoothly meshed at an initial position. A rack and pinion meshing mechanism, wherein a magnet for stopping the pinion is arranged around the pinion. 2. A mechanism in which a rack and a pinion mesh with each other, wherein at least a tooth portion of a gear that rotates in synchronization with the pinion is formed of a magnetic material, and the pinion and the rack are initially meshed with each other when rotation of the pinion is stopped. A rack and pinion meshing mechanism, wherein a magnet for stopping the pinion is arranged around the gear at a position where the gear can be smoothly moved. 3. A mechanism in which a rack and a pinion mesh with each other, in which at least the tooth portion of the pinion is formed of a magnetized member, and when the rotation of the pinion is stopped, the initial meshing between the pinion and the rack can be performed smoothly. A rack-and-pinion meshing mechanism characterized in that a magnetic body for stopping the pinion is arranged around the pinion. 4. A mechanism in which a rack and a pinion mesh with each other, wherein at least a tooth portion of a gear that rotates in synchronization with the pinion is formed of a magnetized member, and the pinion and the rack are initially meshed with each other when rotation of the pinion is stopped. A rack characterized in that a magnetic body for stopping the pinion is arranged around the gear at a position where it can be smoothly operated.
Pinion meshing mechanism.