JP2890800B2 - Magnetic levitation transfer device - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic levitation type transport apparatus that transports an article or the like while a bogie travels while floating along a transport path.

"Conventional technology" In recent years, with the high integration and ultra miniaturization of semiconductor integrated circuits,
High cleanliness is required for the clean room that manufactures it. In such a clean room, a transfer device for transferring silicon wafers and the like needs to minimize the generation of dust, and in a state where the cart floats on the transfer path,
That is, attention is drawn to the fact that a magnetic levitation transfer device that travels without contact is ideal.

3 to 6 are views showing an example of a conventional magnetic levitation type transport device. In these figures, reference numeral 1 denotes a box-shaped frame provided along the transport path,
An opening 1a extending along the transport path is formed. On the ceiling surface of the frame 1, a pair of levitation rails 2L and 2R made of a steel material are respectively erected along the transport path. Similarly, the left and right inner surfaces of the frame 1 are also provided with a steel material. Each of the pair of guide rails 3L, 3R constituted by is constructed. Reference numeral 5 denotes a carriage that travels on the transport path,
The trolley 5 has four levitation / guide electromagnets 7a to 7d facing the lower surfaces of the levitation rails 2L and 2R, respectively, and four guides facing the respective side surfaces of the guide rails 3L and 3R. Electromagnet 8a
To 8d. Further, although not shown, a vertical gap Gv between the rechargeable battery, the floating / guide electromagnets 7a to 7d and the lower surfaces of the floating rails 2L and 2R, and the guide electromagnets 8a to 8d and the guide rail 3L , 3R, the gap sensors for detecting the horizontal gaps Gh between the respective side surfaces, and electromagnets 7a to 7d for floating / guiding from the battery and the electromagnets 8a for guiding based on the detection signals of these gap sensors.
~ 8d to control the excitation current supplied to each
A current control circuit for keeping Gv and the horizontal gap Gh constant at all times is provided.

As shown in FIG. 6, the levitation / guide electromagnet 7a includes a U-shaped primary core 7A and coils 7B and 7C wound around the core 7a. Are arranged in a state where the magnetic poles are aligned in the width direction of the carriage 5.
The other levitation / guide electromagnets 7b to 7d are similarly configured. The trolley 5 floats by the magnetic attraction of the lower surfaces of the levitation rails 2L, 2R by the levitation / guide electromagnets 7a to 7d, and the trolley 5 further falls within the width of the levitation rails 2L, 2R. , The movement in the width direction is restricted. Further, the guide electromagnets 8a to 8d magnetically attract the respective side surfaces of the guide rails 3L and 3R, whereby the movement of the carriage 5 in the width direction is strongly restricted.

Are mounted on the inner bottom surface of the frame 1 at predetermined intervals, and the bogie 5 is vertically opposed to the bogie 5 with a predetermined gap therebetween. The secondary conductor 16 is attached. In this case, the secondary conductor 16 may or may not have an iron core. Further, a carrier 18 is mounted on the upper surface of the carriage 5 via a support 17.
Luggage 19 is loaded on 17.

In such a configuration, the levitation / guide electromagnets 7a to 7d
When the exciting current is supplied to the guiding electromagnets 8a to 8d, the carriage 5 floats. On the other hand, when an alternating current is supplied to the primary coil 15 of the linear induction motor, the bogie 5 is placed on the primary coil 15. A traveling magnetic field in the direction of arrow F shown in the drawing is generated, whereby the truck 5 is accelerated in the direction of arrow F each time it passes above the primary coil 15, and travels by inertia in other sections. As a result, the bogie 5 travels continuously while alternately repeating acceleration and coasting while floating. When the positioning of the carriage 5 is stopped at the station, the primary coil before the station is used.
15 is excited in the opposite phase to generate a traveling magnetic field in the direction opposite to the arrow F, thereby sufficiently decelerating the carriage 5 and then stopping the carriage 5 by a positioning electromagnet or the like. further,
When the power of the battery is consumed and the power sufficient to float the carriage 5 is not generated, the battery is charged by connecting the automatic charging device.

As described above, in the magnetic levitation type transport apparatus, the carriage 5 floats on the transport path and travels in a non-contact state.
If the current control circuit provided in the battery fails or the battery capacity decreases, the guide levitation control fails.
For example, when the levitation control is not performed normally, the bogie 5 falls from the levitation rails 2L, 2R, or when the guidance control is not performed normally (particularly in a curved section), the guide rails 3L, An accident such as the side of the truck 5 coming into contact with the 3R occurs. Such contact of the carriage 5 not only damages the carriage 5 itself and the guide rails 3L and 3R, but also damages an expensive object to be conveyed such as a silicon wafer and disperses dust generated by friction around. And so on. Therefore, in order to prevent these accidents, a landing roller for preventing falling and a movement of the carriage 5 in the width direction as shown in FIG.
Four guide rollers 22,22, ... that regulate within twice the range of
Is provided. In this case, the guide rollers 22, 22,... Are provided so as to protrude from the side surface of the carriage 5 in the left-right direction. The carriage 5 is arranged at a sufficient distance in the left-right direction from the side surface of the carriage 5 so that the four corners of the carriage 5 do not contact the guide rails 3L, 3R. By providing such guide rollers 22, 22,..., The guide rollers 22, 22,. The carriage 5 is protected by contacting the rails 3L and 3R.

[Problems to be Solved by the Invention] By the way, the guide rollers 22, 22,... Applied to the above-mentioned conventional magnetic levitation type transport device are, as shown in FIG.
In order to prevent the four corners of the carriage 5 from contacting the guide rails 3L and 3R, the carriage 5 must be arranged at a sufficient distance in the left-right direction from the side surface of the carriage 5, whereby, in a curved section having a radius of curvature R, The distance Ac must be secured in view of the left and right gap G between the guide rails 3L and 3R, and the distance As must be secured in a straight section. Therefore, there is a problem that the width of the transport path becomes extremely large as compared with the width of the carriage 5.

The present invention has been made in view of the above-described circumstances, and provides a magnetic levitation type transfer device capable of minimizing the width dimension of a transfer path even when a guide roller for restricting movement of a carriage in the width direction is provided. It is intended to provide.

[Means for Solving the Problems] The present invention is directed to a magnetic levitation type transport device in which a bogie travels along a transport path surrounded by guide rails on the left and right sides with a magnetic levitation force. The carriage is rotatably provided in the vicinity of the front and rear ends of the left and right sides of the bogie, and in a curved section of the transport path, approaches a guide rail on the outer peripheral side to regulate the movement of the bogie in the width direction. An outer peripheral guide roller, and a rotatably provided shaft that is provided at a central portion of the side surface with respect to an imaginary straight line connecting the curved center of the transport path and the outer peripheral roller. In a curved section, an emergency inner peripheral guide roller is provided which approaches a guide rail on the inner peripheral side and restricts movement of the carriage in the width direction.

[Operation] According to the configuration described above, in the curved section of the transport path,
Guide rails on the outer peripheral side, emergency outer peripheral guide rollers provided near the front and rear ends of the left and right sides of the bogie approach to restrict the movement of the bogie in the width direction, and to the inner peripheral side guide rails,
The emergency inner peripheral guide rollers provided on the center side of the bogie side are closer than the virtual straight line connecting the curved center of the transport path and the outer peripheral rollers, so as to regulate the movement of the bogie in the width direction. It is possible to arrange all the guide rollers as close as possible to the side surface of the carriage and to be able to abut both guide rollers even on the curved section with a large curvature, so that the curve of the transport path can be adjusted. The distance between the left and right guide rails in the section can be significantly reduced as compared with the related art, and the distance between the guide rails in the straight section can be made closer to the width of the bogie.

"Example" Hereinafter, an example of the present invention will be described with reference to the drawings.

FIG. 1 is a plan view showing the configuration of one embodiment of the present invention.

As shown in the figure, near the front and rear ends of the left and right sides of the carriage 5, outer periphery guide rollers 24, 24,... ing. Also, in the vicinity of the center of the left and right side surfaces of the bogie 5, in the curved section of the transport path, there are provided inner circumference guide rollers 25 approaching the inner circumference guide rail 3L. These guide rollers 24,24,… and 25,2
Are arranged as close as possible to the side surface of the truck 5 and are rotatably mounted on shafts vertically supported by holding members via bearings. In particular, the inner peripheral guide rollers 25, 25,.
The center side of the above-mentioned side surface with respect to the imaginary straight line K1 connecting the center of the curve of R and the outer peripheral guide rollers 24, 24,... And slightly inside the bogie 5 in the width direction of the outer peripheral guide rollers 24, 24,. It is arranged in.

According to such a configuration, as shown in FIG. 1, in the curved section having the radius of curvature R, the distance Bc may be ensured in view of the left and right gap G between the guide rails 3L and 3R. In the straight section, the distance Bs may be secured.

Here, referring to FIG. 2, as compared with the conventional example shown in FIG. 7, the required width dimension Bc ₁ (the left and right gap G is subtracted from the distance Bc) required for the curved section in this embodiment. Dimension) and the required width dimension Bs ₁ required for the straight section
It can be seen that the required widths Ac ₁ and As _{1 of the} conventional example can be significantly narrower. In particular, in this embodiment, since all the guide rollers 24, 24, ... and 25, 25, ... are arranged as close as possible to the side surface of the truck 5, the required width dimension Bs1 in the straight section is determined by the width of the truck. Since the inner guide rollers 25, 25,... Are arranged on the inner side in the width direction of the bogie 5 than the outer guide rollers 24, 24,. Guide rail 3L
, And 25, 25,... Can be brought closer to the bogie 5 than when the guide rollers 24, 24,. Further, the inner peripheral guide rollers 25, 25,... Are arranged closer to the center of the side surface than the imaginary straight line K1 connecting the curved centers of the guide rails 3L, 3R and the outer peripheral guide rollers 24, 24,. Therefore, the outer peripheral guide rollers 24, 24,... And the inner peripheral guide rollers 25, 25,... Simultaneously contact the guide rail 3R and the guide rail 3L, respectively, so that the carriage 5 can be reliably protected in an emergency. .

In the embodiment described above, the guide rail 3R
Has been described as an example of a curved section on the outer peripheral side and the guide rail 3L on the inner peripheral side, but the same effect can be obtained even if the guide rail 3R is a curved section on the inner peripheral side and the guide rail 3L is an outer peripheral side. can get.

[Effects of the Invention] As described above, according to the present invention, in the curved section of the transport path, the emergency outer peripheral guide provided near the front and rear ends of the left and right side surfaces of the bogie on the outer peripheral guide rail. Rollers approach to restrict the movement of the bogie in the width direction, and an emergency guide rail is provided on the inner circumferential side of the guide rail, closer to the center of the bogie than the imaginary straight line connecting the curved center of the transport path and the outer circumferential roller. The inner peripheral guide rollers approach to restrict the movement of the bogie in the width direction, so that all the guide rollers can be arranged as close as possible to the side of the bogie, whereby The distance between the left and right guide rails in the curved section of the road can be significantly reduced as compared with the related art, and the distance between the guide rails in the straight section can be closer to the width of the bogie. The installation space of the transfer path is small, the weight of the transfer path can be reduced, and the effect of simplifying the installation work and reducing the construction cost can be obtained. Furthermore, the guide roller for the inner circumference and the guide roller for the outer circumference can contact the guide rails at the same time, so that the effect that the cart can be reliably protected in an emergency can be obtained.

[Brief description of the drawings]

FIG. 1 is a plan view showing the structure of one embodiment of the present invention, and FIG.
FIG. 3 is a plan view for comparing the embodiment with the conventional example.
FIG. 1 is a partially cutaway side view showing the external configuration of a conventional magnetic levitation transfer device, FIG. 4 is a plan view showing the external configuration of the magnetic levitation transfer device, and FIG. 5 is an external view of the magnetic levitation transfer device. FIG. 6 is a front sectional view showing the configuration of a levitation / guide electromagnet of the magnetic levitation type transport device. FIG. 7 is a relationship between guide rollers and a transport path of the magnetic levitation type transport device. FIG. 5… trolley, 3L, 3R… guide rail (guide rail), 24… outer guide roller, 25… inner guide roller, K1… virtual straight line.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) B65G 54/02 B61B 13/08

Claims (1)

(57) [Claims] 1. A magnetic levitation type transport apparatus in which a bogie travels along a transport path surrounded by guide rails on the left and right sides in a state of being floated by a magnetic levitation force, wherein the bogie is rotatable on a vertically supported shaft. An emergency outer peripheral guide roller which is provided near the front and rear ends of the left and right side surfaces of the bogie and which approaches a guide rail on the outer peripheral side in a curved section of the transport path and regulates movement of the bogie in the width direction; Is rotatably provided on a shaft supported by the shaft, and is provided at a central portion of the side surface with respect to an imaginary straight line connecting the curved center of the transport path and the outer peripheral roller, and a guide on an inner peripheral side in a curved section of the transport path. A magnetic levitation type transport device, comprising: an emergency inner peripheral guide roller for restricting movement of the carriage in the width direction by approaching a rail.