JP3226973B2 - Magnetic levitation transfer device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a non-contact type magnetic levitation transfer in which a carrier is moved by a linear motor or the like along a transport path in a tunnel while the carrier is levitated by the magnetic attraction of an electromagnet. Related to the device.

[0002]

2. Description of the Related Art The above-mentioned magnetic levitation transfer device attracts a transfer table by a magnetic attraction force generated by a magnetic force of an electromagnet to be controlled, and brings the transfer table into a non-contact state above or below an upper surface of a transfer path. The carrier is lifted and held, and the carrier is moved along the carrier path by driving a linear motor or the like. In such a magnetic levitation transfer device, in any case of stopping, holding, and moving the transfer table, the transfer table and the transfer path in the tunnel that is its track maintain a non-contact state. There is no danger of generating dust at the contact portion. Therefore, the magnetic levitation transfer device can be used in a semiconductor manufacturing facility or the like where generation of dust is extremely reduced. By a magnetic levitation transfer device provided in the semiconductor manufacturing facility or the like, a transfer table travels on a transfer path in a tunnel to transfer various components and products.

In such a magnetic levitation transfer device, the transfer table needs to be operated in a high cleanness atmospheric pressure or a high vacuum, and the levitation electromagnet emits a strong leakage magnetic field. The periphery of the carrier is covered with a magnetic shield tunnel for shutting off magnetism and a vacuum shield tunnel for maintaining high cleanliness, for example, high vacuum.

[0004]

In such a tunnel, there are places without windows and places with blind spots. In such places, the position of the carriage that travels in the tunnel cannot be known from outside. The present invention has been made in order to solve such a problem, and an object of the present invention is to provide a magnetic levitation transfer device that allows the position of a transfer table traveling in a tunnel to be easily known from outside the tunnel.

[0005]

According to the present invention, there is provided a magnetic levitation transfer device which lifts a transfer table by an attractive force generated by magnetic force of electromagnets arranged in a transfer path, and switches the transfer table while switching the electromagnets. In a magnetic levitation transport device that travels along the transport path in a tunnel, a detection unit that is disposed near each of the electromagnets and detects the presence or absence of a magnetic force of each electromagnet, and the electromagnet based on the operation of the detection unit A display means for displaying the presence or absence of the magnetic force is provided outside the tunnel.

[0006]

In the present invention, the electromagnets arranged in the transport path are sequentially switched in operation state as the transport table moves to become the magnetic poles to be levitated in order to lift the transport table. The presence or absence of a magnetic force generated by the excitation of the electromagnet is detected by magnetic detection means. The operation of the detection means is transmitted to the display means, and for example, an LED lamp of the display part of the display means outside the tunnel is turned on. Thus, it can be understood that the lit position of the display unit outside the tunnel is the position where the transport table is traveling.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIGS. As shown in FIG. 1, the magnetic levitation transport device according to the present embodiment has a large number of electromagnets 2 arranged in a row on a transport path 1, and the transport table 3 is levitated by magnetic attraction generated by the magnetic force of the electromagnets 2. While traveling in the transport direction B according to the transport path 1. The magnetic levitation transfer device is provided near the electromagnets 2 and detects detection means 4 for detecting the presence or absence of a magnetic force of each electromagnet 2. Based on the operation of the detection means 4, the presence or absence of the magnetic force of the electromagnet 2, A display means 5 for displaying whether the electromagnet is in the operating state or not, for example, disposed outside the tunnel 8 composed of an LED lamp.

A lower portion of an upper cover member 7 forming a magnetic shield tunnel 6 for shielding a magnetic field from the outside is used to maintain a vacuum (or a high cleanness environment such as atmospheric pressure) around the carrier 3. U-shaped lower cover member 9 forming the vacuum shield tunnel 8 of FIG. A linear motor 10 is provided at the center of the bottom plate of the lower cover member 9 so that the transport table 3 housed inside the vacuum shield tunnel 8 and floated travels in the transport direction B.

By exciting the linear motor 10,
An eddy current is generated in the good conductor 15a on the lower surface of the carrier 3 and receives a propulsive force by a spatial moving magnetic field formed by the linear motor 10 so that the carrier 3 moves in the vacuum shield tunnel 8 in the transport direction B.
To travel. The electromagnets are sequentially operated according to the moving direction of the carrier 3, and the magnetic poles to be levitated are switched to sequentially generate an attractive force due to the magnetic force applied to the magnetic target 15 of the carrier 3, so that the carrier 3 is driven by the electromagnet 2. The vehicle travels in the vacuum shield tunnel 8 in a non-contact state while maintaining a predetermined gap with a partition 16 which is located at a lower portion of the lower surface and partitions a space.

FIG. 2 shows the transport table during traveling. In this way, a part (2a) of the electromagnets 2 arranged in the transfer path and accommodated in the magnetic shield tunnel 6 is set in the operating state, and the transfer table 3 is set.
And the electromagnets 2 for floatingly supporting the carrier are sequentially switched as the carrier 1 travels. Therefore, in the state shown in the figure, the electromagnet 2a is in the operating state, and the detecting means 4
“a” detects the magnetic force of the electromagnet 2 a in the operating state, and turns on the LED lamp 26 a as the display means 5 outside the tunnel 8. Therefore, when the carriage 3 travels in the movement direction B,
Since the electromagnet 2 to be supported by the levitating operation is switched as the carrier 3 travels, the lighting state of the LED lamp 26 as the display means 5 outside the tunnel is also sequentially switched as the carrier 3 travels.

Next, the detection means 4 for detecting the presence or absence of a magnetic force of each of the electromagnets 2 arranged in a line and the display means 5 for displaying the detection result will be described. As shown in FIG. 1, in the present embodiment, the detection means 4 is disposed near one electromagnet 2 of a pair of electromagnets 2 arranged side by side. That is, as an example of the sensing position of the detecting means 4, FIG.
As shown in FIG. 3, which is an enlarged view of the portion IV in FIG. 3, each end portion 12a of the yoke 12 facing one electromagnet 2
Is preferably an intermediate position. The detecting means 4 is a magnetic reed switch 21 (FIG. 4) in which the tongue pieces sealed in the glass are attracted to each other by magnetism to be in a closed state.
Magnetic sensors such as a magnetoresistive element 22 (see FIG. 5), which is a circuit element whose electric resistance changes when a magnetic field is applied, are used.

When the reed switch 21 is used,
As shown in FIG. 3, each reed switch 21 arranged at each intermediate position of the one electromagnet 2 is connected in parallel to a circuit to which a power supply is connected. Each reed switch 21 has
Light emitting diode (LED) 26 as resistance and display means
Are connected in series, and when the electromagnet 2 operates and the reed switch 21 is closed by the magnetic force, a predetermined light emitting diode 26a connected to the reed switch 21 is turned on, and the corresponding electromagnet 2 The operating status is displayed.

FIG. 6 shows a case where a magnetoresistive element 22 is provided instead of the reed switch 21 as a detecting means. Each magnetoresistive element 22 is connected in series to the light emitting diode 26 corresponding to each light emitting diode 26 connected in parallel to a circuit to which a power supply is connected.
Therefore, when the electromagnet 2 operates to generate a magnetic field, the electric resistance of the magnetoresistive element 22 corresponding thereto also changes, thereby turning on (or extinguishing) the corresponding specific light emitting diode 26. The traveling place of the carrier 3 at the position of the electromagnet 2 can be easily known from outside the tunnel.

[0014]

Since the present invention is constructed as described above, the display means displays the presence or absence of the magnetic force of each electromagnet in the transport path in the tunnel, that is, the operating state of the electromagnet holding and floating the transport table. From the above display, the position of the carriage that rises and travels in the tunnel can be easily known from outside the tunnel.

[0015] Further, the display means is provided in the transport path in the tunnel.
The presence or absence of magnetic force of each electromagnet, that is, the carrier is held floating
Since the operating status of the electromagnets is displayed, the
wiring Mistakes and disconnections can be checked. Therefore, transport
Each electromagnet in the path generates magnetic force that actually lifts the carriage
It is also possible to check at the final stage whether or not
Become.

[Brief description of the drawings]

FIG. 1 is a cross-sectional structural view of a magnetic levitation transfer device according to an embodiment.

FIG. 2 is a longitudinal sectional structural view of the magnetic levitation transfer device shown in FIG.

FIG. 3 is an enlarged sectional view showing an IV section in FIG. 1;

FIG. 4 is a circuit diagram in the case where a reed switch is used as a detection unit.

FIG. 5 is a circuit diagram in the case where a magnetoresistive element is used as a detecting means.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Conveying path 2 Electromagnet 3 Carriage 21 Reed switch (detection means) 22 Magnetic resistance element (detection means) 26, 26a Light emitting diode (display means)

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Takashi Tanno 11-1 Haneda Asahimachi, Ota-ku, Tokyo Ebara Corporation (56) References JP-A-3-192013 (JP, A) JP-A Sho 50-507 (JP, A) Fully open 1987-188903 (JP, U) (58) Field surveyed (Int. Cl. ⁷ , DB name) B65G 54/00-54/02 B60L 13/02-13 / Ten

Claims (1)

(57) [Claims] 1. A magnetic levitation transfer device in which a carrier is levitated by an attraction force generated by magnetic force of electromagnets arranged in a carrier path, and the carrier is moved along the carrier path in a tunnel while switching the electromagnets. Detecting means for detecting presence / absence of magnetic force of each of the electromagnets disposed near the electromagnet, and display means for displaying the presence / absence of magnetic force of the electromagnet based on the operation of the detecting means, outside the tunnel. A magnetic levitation transfer device, comprising: