JP3393696B2 - Stop positioning 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 stop positioning device, and more particularly, to a contact carriage that moves from the transfer path in a non-contact manner along a transfer path at a predetermined stop position without contact from the transfer path. The present invention relates to a stop positioning device.

[0002]

2. Description of the Related Art In a magnetic levitation transfer device or the like, in which a transfer carriage is floated and held by a magnetic attraction force of an electromagnet, and a transfer carriage is moved by a linear motor in a non-contact manner, in order to unload or load an object The carrier must be accurately positioned and stopped at a station on the road.

FIG. 3 is a sectional view showing an example of such a conventional stop positioning device. In this figure, an iron core 2 which is a secondary magnetic material is fixed to the lower surface of the carrier 1. On the other hand, at the stop position on the transport path 3 side, a primary side electromagnet 4 is arranged with its magnetic pole surface facing the secondary side magnetic material 2. Then, when the carriage 1 reaches the stop position, the coil 5 wound around the primary electromagnet 4 is energized so that the magnetic pole surface 4a of the electromagnet 4 attracts the magnetic pole surface 2a of the secondary iron core 2. The carrier vehicle 1 can be stopped at a predetermined position without contact.

FIG. 4 shows the carrier truck 1 at the time of the stop.
FIG. 6 is an explanatory diagram showing the relationship between the displacement x from the stop position (equilibrium position) and the restoring force f. As can be seen from this figure, when the displacement x is positive, the negative restoring force f acts, and when the displacement x is negative, the positive restoring force f acts. Therefore, the carrier vehicle 1 having inertial force vibrates around the displacement x = 0 (equilibrium point), attenuates while being affected by air resistance, resistance due to eddy current loss, etc., and finally stops at this equilibrium point. Will be done.

A non-contact type stop positioning device of this type is
Since it is a non-contact type that applies a braking force to the transporting vehicle to stop it, it has the advantage of less wear on the contact surface and less risk of dust, and easier maintenance than a system that uses mechanical frictional force. is there. Therefore, if such a stop positioning device can be incorporated into a magnetic levitation transfer device in which the transfer trolley is suspended and driven horizontally by a linear motor, all of the levitation support, drive, and braking of the transfer trolley are non-contact. It is possible to realize a transfer device that can be used in, and it is extremely suitable for use in a clean room where the generation of dust is extremely disliked.

[0006]

However, when the non-contact type stop positioning device described above is incorporated in a magnetic levitation transfer device or the like, the following problems occur. That is, when the carrier carriage that is vertically supported by the magnetic attraction force of the levitation electromagnet and has an inertial force that is driven by the linear motor in the horizontal direction to move is stopped by the stop positioning device shown in FIG. As mentioned above, the carrier truck vibrates around the equilibrium point (x = 0) in the traveling direction, etc., and since it is non-contact, frictional resistance does not occur, and damping force due to air resistance, eddy current loss, etc. acts. Only to do.
For this reason, the vibration is not easily attenuated, and it takes a long time to stop.

The present invention has been made in view of the problems of the prior art, and it is incorporated in a non-contact type transfer device such as a magnetic levitation type, and can be stopped and positioned so that the transfer carriage can be stopped within a short time. The purpose is to provide a device.

[0008]

A stop positioning device of the present invention is a stop positioning device for stopping a transporting carriage traveling along a transport path at a predetermined stop position, one of which is on the stop position side and the other of which is on the stop position side. Two pairs of a pair of members, which are arranged on the side of the carriage and are coupled by a magnetic attraction force,
One of the members, which is coupled by a pair of magnetic attraction forces, is attached to a guide mechanism that restrains the action direction of the magnetic attraction force between the members.

[0009]

With a pair of members, one of which is coupled to the stop position side and the other of which is disposed on the transport vehicle side, coupled by magnetic attraction, vibration of the transport vehicle near the stop position is transmitted to the member on the stop position side. When the member on the stop position side is attached to the guide mechanism, a frictional force acts on the guide mechanism to damp the vibration of the member on the stop position side. When the vibration of the member on the stop position side is damped, the damping force is transmitted to the transport carriage coupled by the magnetic attraction force, and the vibration of the transport carriage is quickly damped. Therefore, since the transport carriage is coupled to the stop position side by the other pair of members coupled by the magnetic attraction force, the transport carriage is stably and promptly positioned at the predetermined stop position.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The first and second embodiments of the present invention will be described below with reference to FIGS.

FIG. 1 is a sectional view taken along the carrying direction showing a stop positioning device according to a first embodiment of the present invention. The carrier 1 carries a carrier 7 such as a wafer in a canned tunnel partition wall 6, is suspended by a levitation electromagnet 8 and is propelled by a linear motor (not shown) to travel in the carrier direction. A vacuum atmosphere is formed inside the canned tunnel partition wall 6, and the details of such a magnetic levitation transport device are disclosed in, for example, International Patent Application PCT / JP93 / 009930 of the present applicant. Two magnetic materials 11 and 12 that are secondary magnetic poles are provided on the lower surface of the carrier 1. The lower surface of the carrier 1 does not have a positioning sensor target used in a normal stop positioning device.

On the other hand, on the stop position side, two electromagnets 13 and 14 as primary side magnetic poles are arranged at positions facing the secondary side magnetic poles 11 and 12 at a predetermined stop position of the carriage 1. . One of the electromagnets 13 forms a holding magnetic pole and is directly fixed to the conveying device fixing surface 15. The other electromagnet 14
Is a guide mechanism 1 for restraining the action direction of the magnetic attraction force acting between the magnetic poles of the electromagnet 14 and the magnetic material 12 on the side of the carriage 1.
6 and its guide mechanism 16 is fixed to the conveyance device fixing surface 15. The sensor 17 is for detecting the carrier vehicle 1 moving near the stop position. The signal of the sensor 17 is transmitted to a control circuit (not shown), and when performing the stop positioning operation of the carriage, the electromagnet 1
By exciting 3 and 14, the electromagnet 13 and the magnetic material 1
1 and a magnetic attraction force is applied between the electromagnet 14 and the magnetic material 12 to couple these members by the magnetic attraction force to stop and position the carriage 1.

Next, the operation of this stop positioning device will be described. First, when the carriage 1 travels inside the canned tunnel partition wall 6 and approaches a predetermined stop position, the sensor 17 detects the entrance of the carriage. Then, the coils of the electromagnet 13 serving as the holding magnetic pole and the electromagnet 14 serving as the damping magnetic pole are energized to excite the respective magnetic poles. When the carrier truck is suspended by the levitation electromagnet and reaches the vicinity of the stop position, a magnetic circuit is formed between the magnetic members 11 and 12 provided on the carrier truck and the magnetic poles of the electromagnets 13 and 14 forming a pair. Magnetic flux flows through each of the two electromagnets 13,
14 and the pair of magnetic materials 11 and 12 are coupled by a magnetic attraction force. Since the carrier vehicle 1 is suspended vertically by the levitation electromagnet 8 and its movement in the vertical direction is restrained, the magnetic attraction force acting between the two sets of electromagnets 13 and 14 and the magnetic materials 11 and 12 is generated by the carrier vehicle. Vibration occurs in the horizontal plane centered on the stop position (equilibrium point) as described in the related art.

However, the electromagnet 14 serving as a damping magnetic pole
Is attached to the fixed surface 15 via the guide mechanism 16, its movement is restricted in the acting direction (vertical direction) of the magnetic attraction force between the magnetic material 12 and the electromagnet 14, and is free in the direction in the horizontal plane. It has a structure that can vibrate. Then, the guide mechanism 16 allows the electromagnet 14 to vibrate in a direction in the horizontal plane, but the friction force is generated due to the mechanical mechanism accompanying the vibration.

On the other hand, in the pair in which the electromagnet 13 serving as the holding magnetic pole and the magnetic material 11 are coupled by the magnetic attraction force, the carriage 1 vibrates near the stop position. The vibration is transmitted to the electromagnet 14 by the pair of the electromagnet 14 serving as a damping magnetic pole and the magnetic attraction force of the magnetic material 12 which are coupled to each other. The electromagnet 14 serving as a damping magnetic pole vibrates along the guide mechanism in a direction in the horizontal plane, and this vibration is rapidly damped by the frictional force. When the vibration of the electromagnet 14 is attenuated, the vibration of the carrier vehicle 1 to which the pair of magnetic materials 12 coupled by the magnetic attraction force is fixed is also rapidly attenuated. Therefore, the carriage 1 is stopped and positioned at the equilibrium position where the magnetic pole faces of the electromagnet 13 and the magnetic material 11 fixed to the fixed face serving as the holding magnetic pole face each other.

When the carrier vehicle 1 is started from the stop position, the control circuit (not shown) stops the energization of the coils to the electromagnets 13 and 14 to release the coupling with the magnetic materials 11 and 12 by the magnetic attraction force. As a result, it is possible to start the vehicle from the stop position by applying a propulsive force in the horizontal direction by a linear motor not shown.

FIG. 2 shows a stop positioning device according to a second embodiment of the present invention. In this embodiment, the guide mechanism 16 is further provided with a damper 18. Other configurations are the same as those in the first embodiment described above, the same elements are designated by the same reference numerals, and the duplicated description thereof will be omitted. The operation of the stop positioning device of this embodiment is similar to the operation of the stop positioning device of the first embodiment described above, but in this embodiment, in addition to the frictional force of the guide mechanism 16, the damping force of the damper 18 acts. Therefore, the vibration of the electromagnet 14 serving as the damping magnetic pole can be reduced more quickly, and as a result, the vibration of the carrier vehicle 1 can be damped more quickly.

In the embodiment described above, the pair of members coupled by the magnetic attraction force is composed of the electromagnet and the magnetic material, but a permanent magnet may be used. Further, the magnetic material fixed to the lower surface of the carrier may be a permanent magnet or an electromagnet as long as it is coupled with a member on the stop position side by a magnetic circuit to form a magnetic attraction force.

Further, in the above-mentioned embodiment, the case where the carrier truck travels in the partition wall of the canned vacuum tunnel by the magnetic levitation carrier device is applied. However, the contact type carrier device having ordinary wheels is applied. Needless to say, the present stop positioning device can also be applied. As described above, various modified embodiments are possible without departing from the gist of the present invention.

[0020]

As described above, according to the present invention,
By attenuating the vibration of the member arranged on the outside of the partition, the transport carriage in the partition can be quickly stopped and positioned without contact. Therefore, it is not necessary to control the stop positioning operation of the carrier by detecting the displacement amount of the carrier. Therefore, a sensor target for stopping and positioning the carriage is not required on the side of the carriage, so that the structure of the carriage is simplified. Since the stop positioning of the transport carriage is performed by coupling the magnetic attraction forces between the members disposed on the transport carriage side and the stop position side, the tunnel partition may be made of a non-magnetic conductor. The transport carriage can be stably stopped and positioned from the atmosphere side through the tunnel partition in a short time. Therefore, it becomes easy to manufacture the partition wall that forms a high cleanliness space such as a vacuum.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of a stop positioning device according to a first embodiment of the present invention.

FIG. 2 is an explanatory diagram of a stop positioning device according to a second embodiment of the present invention.

FIG. 3 is an explanatory view showing a conventional stop positioning device.

FIG. 4 is an explanatory diagram showing a relationship between a displacement X and a restoring force f in a conventional stop positioning device.

[Explanation of symbols]

1 carrier 8 Levitation electromagnet 11,12 Secondary magnetic pole 13,14 Primary magnetic pole 15 Transport device fixed surface 16 Guide mechanism 17 sensors 18 damper

─────────────────────────────────────────────────── ─── Continuation of front page (72) Masao Matsumura 4-2-1, Motofujisawa, Fujisawa-shi, Kanagawa Inside EBARA Research Institute, Inc. (72) Inventor Takeshi Yoshioka 4-2-1, Fujisawa, Kanagawa (56) References JP-A-5-292609 (JP, A) JP-A-5-77126 (JP, A) JP-A-56-136383 (JP, A) (58) Field (Int.Cl. ⁷ , DB name) H02P 7/00 B60L 13/03 B60L 13/04 B65G 54/02

Claims (5)

(57) [Claims] 1. In a stop positioning device for stopping a transport carriage traveling along a transport path at a predetermined stop position, one magnetic attraction force is arranged on one side of the stop position and the other is arranged on the transport carriage side. A pair of members connected by
A stop positioning device, comprising a pair, and one of the members to be coupled by a pair of magnetic attraction forces is attached to a guide mechanism for restraining the action direction of the magnetic attraction force between the members. 2. The stop positioning device according to claim 1, wherein the guide mechanism includes a damper. 3. A sensor is further provided for detecting that the carrier vehicle has entered near a predetermined stop position,
The stop positioning device according to claim 1, wherein a magnetic attraction force is applied between the pair of members based on an approach detection signal of the sensor. 4. The stop positioning device according to claim 1, wherein the action of the magnetic attraction force is canceled based on a start command signal when the transport carriage stopped at the stop position is started. 5. The pair of members coupled by the magnetic attraction force, one of which is an electromagnet, and the other of which is a magnetic material or a permanent magnet. Stop positioning device.