JPH042462B2 - - Google Patents

Description

[Detailed description of the invention] (a) Industrial application field The present invention is applicable to a clean room where a magnetic fluid is interposed between a conveyance path and a plurality of legs of a conveyance table to levitate the conveyance table, and the conveyance table is transported by a linear motor. The present invention relates to a conveying device (hereinafter simply referred to as a conveying device) used for such purposes.

(b) Prior art As a conventional example of this type of conveyance device, for example, a flat movable element of a linear motor provided on a conveyance table has a
A conveyance device is known in which compressed air is injected from below from a number of nozzles provided on a table corresponding to the movable element, and the conveyance table is levitated while being transported by excitation of a stator of a linear motor.

However, the above-mentioned apparatus requires a compressed air source, which increases the equipment cost.
What is even more important is that such conveyance equipment can be used in semiconductor manufacturing factories, precision parts manufacturing factories, etc.
If it is used in a place where the generation of dust is not desired, there is a risk that the flow of the compressed air will actually encourage the generation of dust, making it unsuitable as a conveying device for use in clean rooms and the like.

(c) Purpose The present invention has been made in view of the above circumstances, and provides a conveyance device that does not require compressed air to levitate the conveyance table, has a simple structure, and always transports the conveyance table stably. The purpose is to

(D) Configuration The present invention includes a conveyance path, a conveyance table, and a magnetic fluid, and the conveyance path includes a plurality of stators provided on the upper surface along the conveyance direction, and a plurality of stators provided on the upper surface along the conveyance direction. The carrier has a plurality of dovetail-like grooves with an upper cover to prevent the magnetic fluid from flowing out, and the carrier is made of a non-magnetic conductive material provided on the bottom facing the stator. It has a reaction plate consisting of a reaction plate, a leg part that fits into the groove part, and a permanent magnet provided on the lower end surface of the leg part, and by interposing the magnetic fluid between the groove part and the leg part, the conveyor table can be is characterized in that it is always transported while being levitated from the transport path by magnetic fluid.

(E) Embodiment FIG. 1 is a sectional front view showing an embodiment of the conveying device according to the present invention, FIG. 2 is a sectional view taken along line AA in FIG. 1,
FIG. 3 is a plan view.

In the figure, reference numeral 1 denotes a conveyance path fixed by a frame (not shown). Two substantially dovetail groove portions 13 are formed with the provided cover portion 12.

Reference numeral 2 denotes a stator of a linear motor, which is placed on the upper surface of the conveyance path 1 at predetermined intervals in the longitudinal direction.

Reference numeral 3 denotes a conveyance table, which is composed of a bottom surface 31 on which an object to be conveyed (not shown) is placed, and a pair of legs 32 having an upright T-shaped cross section and each having a permanent magnet 4 on its lower end surface. The leg portions 32 are arranged in the groove portions 13 of the conveyance path 1, respectively, and
is supported in two places.

The bottom surface 31 acts as a reaction plate of the linear motor, and is made of a non-magnetic conductive material such as aluminum or copper plate, and faces the stator 2 with a predetermined gap therebetween to form the linear motor. do.

Reference numeral 5 denotes a magnetic fluid, which is provided between the lower end surface of the leg portion 32 and the bottom surface of the conveyance path 1 (groove portion 13) so that the magnetic field of the permanent magnet 4 acts thereon. The magnetic fluid 5 is a well-known colloidal solution in which the surface of magnetic fine particles such as ferrite is coated with long-chain unsaturated fatty acids and dispersed in a solution using a surfactant.

Therefore, since the magnetic fluid 5 is magnetically an aggregate of molecules having a permanent magnetic moment and has superparamagnetic properties, the legs 32 of the carrier 3
As a result, each magnetic fluid 5 is magnetized by the influence of the magnetic field generated by each permanent magnet 4 provided on the lower end surface of the permanent magnet 4 .
It will be moved together. At this time, since the conveyance table 3 is supported at two places and driven by a linear motor, the conveyance table 3 can always be moved in a stable state. Further, by providing the upper cover portion 12 on the conveyance path 1, it is possible to prevent the magnetic fluid 5 from flowing out from the inside of the conveyance path 1 and further reduce the amount of evaporation of the solvent of the magnetic fluid 5. Note that the control means for controlling the speed, stopping, etc. of the conveyance table 3 are well known, and therefore their explanation will be omitted.

Note that the present invention is not limited to the embodiment shown in the drawings, and the present invention is not limited to the embodiment shown in the drawings. It is also possible to place a plurality of sets of children 2 in parallel on the surface of the conveyance path.

(f) Effects According to the present invention, the following effects are obtained as explained in the above embodiments.

(1) The conveyor table is supported by a plurality of legs, and the conveyor table is supported by the magnetic force of each permanent magnet provided on the lower end surface of the legs and the magnetic fluid placed in multiple places on the bottom of the conveyor path. Even with a simple structure in which the conveyance table is floated and transported by a linear motor, the conveyance table can always be transported stably.

(2) The carrier can be levitated from the carrier simply by putting a predetermined amount of magnetic fluid into the carrier, which is extremely simple compared to conventional compressed air levitation means. A stator is attached to the top of the cover to make effective use of space and create an efficient linear motor.
The size of the conveyance path can be reduced, and the overall size of the conveyance device can be reduced.

(3) By providing a cover section above the conveyance path, it is possible to prevent the magnetic fluid from flowing out from the inside of the conveyance path and further reduce the amount of evaporation of the solvent of the magnetic fluid.

(4) Since the device does not generate dust and is simple, it is excellent in terms of equipment cost and maintenance cost, and is particularly suitable as a conveying device in a clean room.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional front view showing an embodiment of the conveying device according to the present invention, FIG. 2 is a cross-sectional view taken along line A-A in FIG.
FIG. 3 is a plan view. 1... Conveyance path, 2... Stator, 3... Conveyance platform,
31...bottom, 32...leg, 4...permanent magnet,
5...Magnetic fluid.

Claims (1)

[Claims] 1 It is equipped with a conveyance path, a conveyance table, and a magnetic fluid, and the conveyance path includes a plurality of stators provided on the upper surface along the conveyance direction, and a plurality of stators provided on the upper surface along the conveyance direction to the outside of the magnetic fluid. The carrier has a plurality of dovetail-like grooves with an upper cover to prevent the outflow of the liquid. , has legs that fit into the grooves and permanent magnets provided on the lower end surfaces of the legs, and the magnetic fluid is interposed between the grooves and the legs so that the carriage is always transported by the magnetic fluid. A conveyance device used in clean rooms, etc., characterized in that it is transported while being floated off the road.