JPS61150925A - Linear motor conveyor for wafer - Google Patents

Abstract

PURPOSE:To enable to convey a carrier pallet and wafer thereon in the stable condition free from dust, by driving the pallet with a linear motor, and by floating up the load with compressed air. CONSTITUTION:The conveying route 2 is furnished with the primary side of a linear motor 3, and the reaction plate of the bottom of the carrier pallet 6 is used as the secondary side of the linear motor 3. The magnetic flux of the primary side of the linear motor 3 gives a propelling power to the reaction plate to move the pallet 6 with the wafer on it, in the direction of the arrow. In this case, compressed air is injected through nozzles 1C of the carrier table 1 to keep the pallet 6 in a floating position over the table 1, and conveys the pallet 6 and the wafer along the conveying route 2 in the condition free from dust.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a method for electrically transporting wafers through a clean room interior.

Conventional technology Conventional wafer electric transmission special transmission includes a device in which a comb with a wafer placed on it travels directly on a conveyor rail, but this device has a mechanical friction part that generates dust and reduces durability. Point i! There was one question.

Problems to be Solved by the Invention The present invention uses a linear motor to move the *i pallet on which a container for storing wafers is placed and levitate it using compressed air.
To provide an air transport device for wafers capable of stably transporting wafers without generating any dust.

Means for solving the problem: A container for storing wafers, a transfer pallet for placing the container, a transfer path for transferring the transfer pallet, a linear motor provided on the transfer path, and a main body attached to the transfer pallet. The reaction plate of the linear motor is used to inject compressed air from a transfer table provided on the surface of the conveyance path to levitate the conveyance pallet, and the thrust of the linear motor causes the conveyance pallet on which containers containing wafers are placed to be transferred along the conveyance path. It is characterized by

EXAMPLE Hereinafter, an electric transmission device which is an example of the present invention will be explained in detail with reference to FIGS.

In this case, W is the weight of the object to be transported, which is the weight of a large number of silicon wafers stored therein, and the container is conveyed through a valley, which is on the top of the toy +C@
Straight line, bending S designed to be carried to the destination
This conveyance path W consists of a conveyance table / and an electrical transmission duct which is integrally installed under the conveyance table /, and the conveyance table / is centered on the center line of the comb conveyance path. It is made of a base magnetic material such as aluminum, stainless steel, etc., with a symmetrical cross section, and nozzle ICs are perforated in the top/turtle and sides of the top, respectively, to supply high-pressure air into the duct. is ejected from the nozzle to levitate a transport pallet that is transported by a linear motor on a transport path. In addition, in the center of the conveyance table/, linear motors J are electrically detected at appropriate intervals in the conveyance direction at the starting point of the conveyance path 'a, a fixed point, and one other place.

A high-pressure duct (J) that allows high-pressure air (compressed air) to flow along the electrical transmission duct is installed, and a pressure cut-off valve is inserted between the high-pressure duct J and the electrical transmission duct 2 to allow close reading between the two ducts. High pressure duct! A compressor 7 and other pressure sources are connected to. Further, a transport pallet d is mounted on the transport table, and at least the +111 beam of the pallet is made of one plate, a steel plate, an aluminum plate, etc., so that thrust can be obtained by a near motor, and the table is arranged so as to straddle the transport table. At the same time, a support ≦b is placed on the upper part of the conveying pallet beam action plate 11, and the transported object is placed on this support.
The pedestal jC is inclined with respect to the one-row direction. Further, a plurality of propulsion blades 4 are provided at one end of the reactor plate 1, and a plurality of these propulsion blades 4 are provided. In the illustrated embodiment, two propulsion blades Cζ are provided on the upper surface of the reaction plate, and a total of four propulsion blades are provided on each side of the left and right sides, but the number of these propulsion blades can be determined arbitrarily. These propulsion vanes are arranged on side plates 11 facing each other at a required interval.
a, a plurality of small feathers ah, ah... with 4j0 and other arbitrary angular changes are used as a single body, and 1
The propulsion blades are made of plasti-1 or the like in order to reduce the weight of heavy electrical equipment.

Then, with the arm of the dovetail conveying device made as described above, the object to be conveyed is placed on the receiving pallet 7, and the operation 6ζ of transporting it to the destination is carried out.
This will be explained below.

First, the compressed air made by compressor 7 is sent to the high-pressure duct! The liquid is sent into the duct of the conveyance path through the nozzle /c, and is ejected above the conveyance table. Then, this ejected high-pressure air presses the bottom reaction plate ta of the transport pallet≦ upward, so that the transport pallet t floats up. When a current is supplied to drive the motor 3, the bottom reaction plate d of the electric transmission pallet l acts as the secondary side of the linear motor, and obtains a propulsive force by the primary magnetic flux of the linear motor. Therefore, the conveyance pallet d is moved in the direction indicated by the arrow in the third column.

Since the conveying pallet 1 is conveyed while being floated by compressed air while being propelled by a linear motor, it can be conveyed stably without generating any dust. Therefore, the wafers stored in the container placed on the transport pallet tH can be transported stably without being affected by dust. Like, always barking in a certain direction! IIk is missed, the stability in the transport direction is improved, and the vibration of the silicon wafer due to inertial force when the transport pallet is started or stopped is reduced. Therefore, damage to the silicon wafer, generation of foreign matter, and adhesion of foreign matter to the silicon wafer can be reduced, and the silicon wafer in the container, that is, the object to be transported, can be transported stably and reliably. In this way, steady conveyance is performed.

By the way, if the Slet Slet is stopped for some reason (power outage, failure, etc.) at a location where there is no linear motor drive unit, compressed air with a pressure slightly higher than the compressed air during steady state ia delivery will be supplied by the pressure switching valve. By switching and blowing the small propulsion blades 4b, the transport is carried out in the direction shown by the arrow in FIG. In other cases, the compressed air may be ejected from the entire conveyance path, or the entire length of the conveyance path may be divided into several blocks, and multiple pallet position detectors may be assigned as appropriate. It is also possible to eject only the relevant block, and return to the origin while sequentially switching the block based on signals from the potential detection hand as the block is being transported.

Effects of the Invention According to the present invention, since the transport pallet is transported without contacting the transport table, no dust is generated during transport, and there is no dust generated by shaking the conveyed material, so wafers that are sensitive to dust can be used. It is suitable for transporting.

[Brief explanation of the drawing]

FIG. 1 is a direct cut-away view showing one embodiment of the conveying device of the present invention, FIG. 5 is a side view showing the said one embodiment, FIG. FIG. 4 is a sectional view of the same. /66. Transport table co00. Repellent duct J,', linear motor 460. Propulsion vane joo, high pressure duct tlo, feeder pellet 70. , compressor t60. Container D61 containing wafers. pressure switching valve

Claims (1)

[Claims] (1) A container for storing wafers, a transport pallet for placing the container, a transport path for transporting the transport pallet, a primary side of a linear motor provided in the transport path, and a rear axis of the linear motor for connecting the bottom of the transport pallet. As a yon plate,
The wafer is characterized in that compressed air is injected from a transport table provided on the surface of the transport path to levitate the transport pallet, and the transport pallet on which the container containing the wafer is placed is transported along the transport path by the thrust of the linear motor. linear motor conveyance device.