JP2006298567A - Overhead traveling vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an overhead traveling vehicle for performing delivery/receipt of an article by lifting of a lifting base between a load port 8 at a ground side and it and comprising a traveling rail 4 provided in a ceiling space; a traveling truck 12 traveling along the traveling rail; a drive lifting part 20 supported on the traveling truck; and the lifting base 22 lifting by operation of a hanging material 24 at the drive lifting part, in which obstacle sensors 28a, b for monitoring an obstacle at a lower side are provided on the lifting base. <P>SOLUTION: Since the obstacle sensors are arranged not on a body frame of the overhead traveling vehicle but on the lifting base, when the lifting base is descended, the obstacle is monitored at a position near the load port and can be certainly detected. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an overhead traveling vehicle, and more particularly to monitoring an obstacle near a load port.

  The overhead traveling vehicle moves up and down the elevator platform to deliver goods to and from the load port on the ground side, and travels along the traveling rail. When raising and lowering the platform, it is dangerous if there are people or items that are accidentally left behind in the vicinity of the load port, so it is necessary to detect obstacles near the load port. In a conventional overhead traveling vehicle (not shown), an obstacle sensor is provided on the fall prevention cover of the overhead traveling vehicle to monitor the load port. However, the distance from the fall prevention cover to the load port is large, and the monitoring distance A long obstacle sensor was needed.

An object of the present invention is to make it possible to reliably detect an obstacle even with an obstacle sensor having a short monitoring distance when raising and lowering a lifting platform.
An additional problem in the inventions of claims 2 and 3 is to more reliably detect an obstacle.

  According to the present invention, a cart that travels along a traveling rail provided in a ceiling space, an elevating drive unit that is directly or indirectly supported by the cart, and lifted / retracted by a lifting / unwinding material in the elevating drive unit An overhead traveling vehicle including an elevator platform is provided with an obstacle sensor for detecting an obstacle below the elevator platform.

  Preferably, the overhead traveling vehicle delivers articles to and from the load port on the ground side by the lifting platform, wherein the load port has a passage space on one side and a processing device space on the other side. The obstacle sensor is arranged on the passage space side of the lifting platform.

  Particularly preferably, the article is placed on the load port in a posture in which a cut corner is positioned on the side of the passage space, and the obstacle sensor is disposed on the upper portion of the corner.

  In the present invention, since the obstacle sensor is arranged on the lifting platform instead of the fall prevention cover or the main body frame of the overhead traveling vehicle, the obstacle can be detected at a short distance when the lifting platform is lowered. This increases the reliability of obstacle detection.

  Here, if the obstacle sensor is arranged on the passage space side of the elevator platform, it is possible to reliably detect a human body trying to access the load port from the passage and an article that is inadvertently placed near the load port.

  If the obstacle sensor is arranged at the upper part of the corner of the article, the obstacle can be detected more reliably through the corner where the article is cut.

  In the following, an optimum embodiment for carrying out the present invention will be shown.

  1-4 and an Example and its modification are shown in FIGS. In these drawings, 2 is an overhead traveling vehicle, which travels along a traveling rail 4 provided in a ceiling space such as a clean room, 6 is a processing device provided in the ground space of the clean room, and the overhead traveling vehicle 2 is a processing device 6. The article 10 is delivered via the load port 8. The load port refers to a facility on the ground side where the overhead traveling vehicle 2 delivers the article, and may be provided at a place other than the processing device.

  The overhead traveling vehicle 2 includes a traveling carriage 12 and travels in the traveling rail 4, and supports the lateral feed unit 16 by the frame 14. The lateral feed unit 16 laterally feeds the θ drive 18, and the θ drive 18 rotates the elevating drive unit 20 in a horizontal plane so that the article 10 is oriented to be transferred to the load port 8. The elevating drive unit 20 elevates and lowers the elevating platform 22 with a suspension material 24 such as a wire, rope, or belt, and grips and conveys the article 10 with a chuck 26. The lateral feed unit 16 and the θ drive 18 need not be provided. In that case, the elevating drive unit 20 can be directly supported by the traveling carriage 12.

  There is a load port 8 directly below the traveling rail 4, and there is a processing device 6 on one of the left and right sides when viewed from the traveling direction of the overhead traveling vehicle 2, that is, the longitudinal direction of the traveling rail 4. There is a passage 29 on the opposite side. An operator or the like may access the load port 8 in addition to the overhead traveling vehicle 2, and articles may be inadvertently placed near the load port 8. Therefore, a pair of front and rear obstacle sensors 28a and 28b are provided on the lifting platform 22 in order to detect a human body and articles near the load port 8.

  A pair of protrusions 40 and 40 are provided on the side of the passage 29 before and after the elevator platform 22 so that the tips protrude from the R portion 32 of the article 10 toward the passage 29, and obstacle sensors 28 a and 28 b are provided at these portions. The obstacle sensors 28a and 28b are, for example, laser distance meters, and monitor the monitoring range 38 within a predetermined angle and within a predetermined distance from the obstacle sensors 28a and 28b by changing the direction of the laser beam in a fan shape. Reference numeral 39 denotes a lower end of the monitoring range, and the monitoring range 38 is arranged obliquely so as to avoid the load port 8, and the lower end 39 is arranged at a position lower than the load port 8. Alternatively, the monitoring range 38 may be substantially vertical, and the lower end thereof may be positioned higher than the load port 8.

  The article 10 is a semiconductor transport cassette or the like, and the load port 8 has a front surface of the article 10 on the processing apparatus 6 side, and a lid 34 is attached to this portion. There is a flange 36 at the upper center of the article 10, and the flange 36 is gripped by the chuck 26 of the overhead traveling vehicle 2. When the article 10 is viewed from the upper surface side, the two corner portions on the rear surface side are cut to become the R portion 32, and the cut surface is vertical. The protrusion 40 protrudes beyond the R portion 32 toward the passage 29, and obstacle sensors 28a and 28b are provided in this portion.

  FIG. 3 shows the control system of the obstacle sensors 28a, 28b. The carriage side control unit 42 provided in the elevation drive unit 20 or the like transfers the height of the elevation table to the elevator table side control unit 44 provided in the elevator table 22. Send a signal. The monitoring range of the obstacle sensors 28a and 28b is changed by raising and lowering the lifting platform 22, and for example, the lower end 39 thereof is constantly at a constant height. Then, detection signals from the obstacle sensors 28a and 28b are sent to the control unit 42 via the control unit 44, and the obstacles are detected.

In the embodiment, the following effects can be obtained.
(1) Since the obstacle sensors 28a and 28b are attached to the lifting platform 22, the obstacle near the load port can be detected at a closer distance as the lifting platform is lowered. This makes it possible to use an obstacle sensor with a short monitoring distance.
(2) A pair of obstacle sensors 28a and 28b are provided at the front and rear, and detected at a position beyond the R portion 32 of the article 10. For this reason, the position in the immediate vicinity of the load port 8 can be monitored, and the reliability of detection increases.
(3) Since the monitoring range is changed as the elevator is raised and lowered, accurate detection is possible.

FIG. 4 shows a modification. In this modification, a protrusion 46 is provided at the center in the front-rear direction near the passage 29 of the lifting platform 22 so as to exceed the center of the back surface of the article 10, and the obstacle sensor 28 is provided at this portion. Similarly, the monitoring range 48 is monitored, and the lower end 49 may be located above the load port 8 or outside the load port 8 and below the load port 8. Comparing the modification of FIG. 4 with the embodiment of FIG. 2, the embodiment of FIG. 2 can also detect an obstacle on the side of the load port 8, but is difficult in the modification of FIG. Further, in the embodiment of FIG. 2, since the protrusion 40 is provided on the R portion 32, it is possible to monitor while avoiding the back surface of the article 10 with a shorter protrusion. For this reason, it is possible to monitor at a position closer to the article 10. In other respects, the modified example of FIG. 4 is the same as the example of FIG. 2, and in particular, the structure of the overhead traveling vehicle and the monitoring range of the obstacle sensor are changed according to the height of the lifting platform. is there.

Side view showing the overhead traveling vehicle of the embodiment monitoring an obstacle near the load port The main part top view with the partial notch part of an Example which shows the monitoring range from the sensor provided in the lifting platform The block diagram which shows the control system of the sensor in the execution example The main part top view with the partial notch part of a modification which shows the monitoring range from the sensor provided in the platform

Explanation of symbols

2 Overhead traveling vehicle 4 Traveling rail 6 Processing device 8 Load port 10 Article 12 Traveling carriage 14 Frame 16 Cross feed unit 18 θ drive 20 Lifting drive unit 22 Lifting platform 24 Suspension material 26 Chuck 28 Obstacle sensor 29 Passage 30 Fall prevention cover 32 R section 34 Lid 36 Flange 38, 48 Monitoring range 39, 49 Lower end 40, 46 of monitoring range Projection 42 Carriage side control unit 44 Lifting platform side control unit

Claims (3)

A carriage that travels along a traveling rail provided in a ceiling space, an elevating drive unit that is directly or indirectly supported by the carriage, and an elevating platform that moves up and down by feeding / winding the suspension material at the elevating drive part In the overhead traveling vehicle provided,
An overhead traveling vehicle comprising an obstacle sensor for detecting an obstacle below the elevator platform. The overhead traveling vehicle delivers articles by raising and lowering the lifting platform with the load port on the ground side, where the load port has a passage space on one side and a processing device space on the other side, The overhead traveling vehicle according to claim 1, wherein the obstacle sensor is disposed on a passage space side of the elevator platform. 3. The overhead traveling vehicle according to claim 2, wherein the article is placed on a load port in a posture in which a cut corner is positioned on the side of the passage space, and the obstacle sensor is disposed on an upper portion of the corner. .

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