JP2001249718A - Collision preventing device for carrier in rail carrying device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent each carrier from colliding with each other in a rail carrying device in which plural carriers are allowed to continuously travel guided by a rail. SOLUTION: A semi-circular arch-shaped reflector 3 is set along a rail R outside a curved part R1 of the rail R, and a light L projected from a rear carrier V is reflected on the reflector 3 so as to be butted to a preceding carrier V', and a reflected light L' is received so that a distance between the two front and rear carriers V' and V can be detected, and when the distance is made not more than a fixed value, the rear carrier V is decelerated or stopped.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rail transport device in which a plurality of transport vehicles are guided by rails and run in a row at a predetermined interval.

[0002]

2. Description of the Related Art In semiconductor manufacturing factories, hospitals and the like, a rail transport device E is installed for transporting loads. As shown in FIG. 8, the rail transport device E
The vehicle includes a rail R, and a number of transport vehicles V guided by the rail R and running in a direction of an arrow P at predetermined intervals. In the present specification, when two specific vehicles V are shown among a large number of vehicles V, they are described as “rear vehicle V” and “immediately preceding vehicle V ′”. A light L is projected on the front surface of the body of each carrier V to strike the carrier V 'immediately before,
An optical sensor device 1 for receiving the reflected light L ′ and detecting the distance between the two transport vehicles V and V ′ is attached. Each transport vehicle V travels on the rail R while emitting light L from the light emitting unit of the optical sensor device 1. Each transport vehicle V stops at a predetermined station S in order to load and unload the load. Further, as shown in FIG. 9, when the transport vehicle V travels on a curved portion R ₁ of the rail R, their travel speed is reduced. For this reason, two consecutive vehicles V,
There is a case where the distance of V ′ becomes short. However, the two optical vehicles V,
The distance V 'is detected, and when this distance becomes equal to or less than a predetermined value, the rear transport vehicle V is decelerated or stopped. This prevents collision between the two transport vehicles V and V '. This effect is the same when the transport vehicle V approaches not only the immediately preceding transport vehicle V 'but also an obstacle near the rail R.

However, since the light L travels straight, as shown in FIG. 9, the transporting vehicle V traveling on the straight line portion R ₂ of the rail R immediately before traveling on the curved portion R ₁ of the rail R. Is extremely difficult to detect. In such a case, when the rear carrier V approaches very close to the immediately preceding carrier V ′, the immediately preceding carrier V ′ can be detected, so that the two vehicles V and V ′ collide. There is a risk.

[0004] In order to prevent the above-mentioned problems, a collision prevention device A 'shown in FIG. 10 is known. The collision prevention device A 'will be described. The curved portions R ₁ of the rail R, a plurality of pairs (in FIG. 10 three pairs) and projector 51 of the light receiver 5
2 are installed. Light 5 emitted from each projector 51
3, the curved portion R ₁ of the rail R diagonally across, is received corresponding to each light receiver 52. The signal from each light receiver 52 is sent to a logical operation unit 54. Signals from the photodetector 52, the logically calculated by logic unit 54, are sent to the no-entry projector 55 installed in the inlet portion 2 of the curved portions R ₁ of the rail R. That is, at least one light receiver 52
Only when the vehicle does not receive the light 53, the entry prohibiting light 55 is operated, and the entry prohibiting light 55
a is emitted.

[0005] The immediately preceding transport vehicle V 'is located on the curved portion R of the rail R.
₁When traveling, at least one floodlight 51
The light 53 emitted from the light source is blocked. Then, the above-mentioned no entry
The entry prohibition light 55a is emitted from the stop light projector 55. Leh
The straight part R of R_TwoSensor of the transporting vehicle V behind the vehicle
When the device 1 receives the entry prohibition light 55a, the transport
The vehicle V is decelerated or stopped. Then, the immediately preceding transport vehicle V '
Is the curved part R of the rail R ₁All the light coming out of
Entry is prohibited because light 53 of detector 51 is received by light receiver 52
The light 55a is extinguished, and the trailing vehicle V moves to the curved portion R
₁Can be entered. By doing so,
Collision between the two transport vehicles V and V 'is prevented.

However, the above-described collision prevention device A 'is expensive because it uses a plurality of pairs of light emitters 51 and light receivers 52, and requires a large amount of work. Also, rail R
For the transport vehicle V at the inlet portion 2 of the curved portions R ₁ is liable to congestion, poor driving efficiency of the transport vehicle V.

Further, as shown in FIG. 9, the curved portion R ₁ of the rail R is often provided near the wall surface W. In such a case, the light L emitted from the transport vehicle V is
Is detected as an obstacle, the transport vehicle V stops.

[0008]

SUMMARY OF THE INVENTION The present invention has been made in consideration of the above-described problems, and has been developed in consideration of the above-described problem. An object of the present invention is to prevent a collision between two transport vehicles by enabling the distance between two transport vehicles traveling back and forth to be detected.

[0009]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention is directed to a rail transport device in which a number of transport vehicles are guided by rails and run continuously at predetermined intervals. An optical sensor device for detecting the distance between the vehicle and the immediately preceding transport vehicle is attached, and between two successive transport vehicles, the light emitted from the optical sensor device of the rearward transport vehicle is immediately forwarded. A device that detects the distance between the two transport vehicles and detects the distance between the two transport vehicles, and when the distance is equal to or less than a predetermined value, decelerates or stops the rear transport vehicle to prevent collision between the two transport vehicles, Outside the curved portion of the rail, a reflector is provided substantially along the rail, and the light emitted from the optical sensor device of the rear transport vehicle is reflected by the reflector to form a curved portion of the rail. Hit the transport vehicle immediately before traveling to It is characterized in that the detectable distance of the two conveying vehicle traveling behind the other the parts.

A large number of transport vehicles are guided by rails, and run continuously while projecting light forward from an optical sensor device attached to each transport vehicle. This light impinges on the immediately preceding transport vehicle, and the reflected light is received, whereby the distance between itself and the immediately preceding transport vehicle is detected. When this distance becomes equal to or less than a predetermined value, the rear carrier is decelerated or stopped. The reflection plate constituting the collision prevention device according to the present invention is installed outside the curved portion of the rail in plan view and substantially along the rail. The light emitted from the optical sensor device of each carrier is reflected inside by the reflection plate and hits the carrier immediately before traveling on the curved part of the rail. Then, the reflected light is received by the optical sensor device. In this way, the distance between the two consecutive vehicles is detected, and the rear vehicle is decelerated or stopped according to the distance. As described above, the collision prevention device for a transport vehicle according to the present invention can detect the distance between two consecutive transport vehicles only by attaching the reflector to the outside of the rail. In other words, the collision between the transport vehicles is prevented by the inexpensive and simple device. In addition, a plurality of transport vehicles can be run in a line on the curved portion of the rail, and the degree of deceleration or stop of the transport vehicles is reduced, so that the travel efficiency of the transport vehicles is improved. Further, it is also possible to detect an obstacle other than the immediately preceding transport vehicle.

In the case where the reflection plate is continuously mounted, the light emitted from the optical sensor device of the carrier is always reflected inside by the reflection plate. For this reason, even if the curved portion of the rail is provided near the wall surface, the carrier does not detect the wall surface as an obstacle.

When the curved portion of the rail has a semicircular arc shape and the traveling direction of the carrier is changed by 180 ° before and after the curved portion, the light emitted from the carrier is transmitted a plurality of times by the reflector. Is reflected. For this reason, the detection accuracy of the immediately preceding conveyance vehicle in the curved portion of the rail is improved.

[0013] The curved portion of the rail is a quarter-arc shape,
When the traveling direction of the transport vehicle is changed by 90 ° before and after the curved portion, not only the inside of the curved portion of the rail but also the transport vehicle V immediately after exiting from the curved portion can be detected.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in more detail with reference to embodiments. Figure 1 is a plan view of the anti-collision device A ₁ of the first embodiment of the present invention, FIG 2 is also a side sectional view, FIG. 3 is a same perspective view. As shown in FIGS. 1 to 3, in a semiconductor manufacturing plant, a hospital, or the like, a large number of carriers V are guided by rails R at predetermined intervals, and arrows P
The rail conveyance device E which runs in a row in the direction of is installed. The anti-collision device A ₁ of the first embodiment of the present invention is provided in the curved portion R ₁ in the rail transport device E. The curved portions R ₁ is semicircular, the running direction of the transport vehicle V before and after the curve portion R ₁ 180
° Switched. The rail transport device E of the present embodiment has a configuration in which a number of transport vehicles V are self-propelled while straddling a rail R, and luggage (not shown) is provided on the upper surface of each transport vehicle V. Be loaded.

[0015] First, a description will be given anti-collision device A ₁ of the first embodiment. As shown in FIGS. 1 to 3, the rail R is bent in a semicircular shape, and a curved portion R ₁ is formed. Then, on the outer side of the rail R in the curved portion R _1, reflector 3 of a semicircular arc shape along the rail R is attached. The reflecting plate 3 of this embodiment is made of a stainless steel plate, and its inner part (reflecting surface 3a) is a mirror surface. Then, mounted from the inlet portion 2 of the curved portions R ₁ of the rail R toward the exit section 4. Between the curved portion R ₁ of the rail R and the reflection surface 3a of the reflection plate 3, a number of transport vehicle V
Have enough clearance to travel.

An optical sensor device 1 is mounted on the front of each carrier V. Next, a method of measuring the distance between two successive vehicles V and V ′ using light L will be described. The method of measuring the distance between two vehicles in front of and behind,
Generally, there are three things: That is, a method of measuring a distance by the amount of reflected light, a method of measuring a distance by a time difference between light emission and reception,
And a method of measuring a distance at a light receiving (spot) position on a PSD using a PSD (two-dimensional position detecting element) and an LED (light emitting diode) (principle of triangulation). here,
In the reflected light amount detection method, for example, an infrared LED is used as a light source, and light is emitted toward the back of a vehicle ahead. If the amount of return reflected light from the back of the vehicle exceeds a certain value, it is determined that the two vehicles have entered the close range, and the rear vehicle is decelerated and further stopped. The time difference method of light emission / reception involves projecting light with a deviated intensity to a preceding vehicle, receiving reflected light from the preceding vehicle, and measuring the distance based on the time difference between the two.
In the method of using the PSD, the mounting position of the LED and PSD is set to a fixed distance in advance, the LED light is emitted to the vehicle in front, the returning light is received by the PSD, and the light receiving position on the PSD to the vehicle in front at that time. The distance is measured. This method is based on the principle of triangulation.

In the case of this embodiment, the distance is measured based on the amount of reflected light. That is, light is projected from the rear transport vehicle V to the rear surface of each transport vehicle V, and the return light amount at a standard distance is determined. That is, when the regression light amount exceeds the set value, the following transport vehicle V is decelerated and further stopped according to the degree. In the case of the present embodiment, as shown in FIG. 4, when the distance between two successive vehicles V and V ′ exceeds about 3 m, the rear vehicle V runs at a normal speed. . Then, when the immediately preceding transport vehicle V ′ stops at a predetermined station S (see FIG. 8) for loading and unloading the load, the distance to the rear transport vehicle V becomes shorter. When this distance becomes about 3 m or less, the rear carrier V decelerates, and stops when it becomes about 0.5 m or less. When the loading / unloading of the load of the preceding transport vehicle V 'at the station S is completed, the transport vehicle V' travels again, and when the distance between the transport vehicles V and V 'exceeds about 0.5 m, the transport of the rear transport vehicle V' is performed. Car V starts running.

[0018] The description of the operation of the collision preventing device A ₁ of the first embodiment of the present invention. As shown in FIG. 1, the transport vehicle V travels in a direction indicated by an arrow P on a straight portion R ₂ of the rail R. Light L is always projected forward from the optical sensor device 1 of the transport vehicle V. This light L is reflected by the reflecting surface 3a of the reflecting plate 3.
At the first reflection point 5, the light is reflected inside the reflection plate 3. Since the reflecting plate 3 has a semicircular shape, the light L reflected at the first reflecting point 5 is reflected by the reflecting plate 3.
The light travels substantially along the curvature direction, and is similarly reflected at the second reflection point 6. As described above, the light L emitted from the optical sensor device 1 of the transport vehicle V travels substantially along the curved direction of the reflector 3 while being reflected by the reflection surface 3a of the reflector 3 a plurality of times.

[0019] Here, as shown in FIG. 1, it is assumed that immediately preceding guided vehicle V 'is traveling through the curved portions R ₁ of the rail R. When the light L emitted from the optical sensor device 1 of the rear transport vehicle V and reflected by the reflection surface 3a of the reflector 3 hits the immediately preceding transport vehicle V ′, the reflected light L ′ is reflected by the rear transport vehicle V ′. Is received by the optical sensor device 1. In FIG. 1, the trajectory of the light L projected from the rear carrier V is indicated by a dashed-dotted line, and the light trace of the reflected light L ′ is indicated by a dashed-dotted line. In this case, the distance d ₁ from the optical sensor device 1 behind the transport vehicle V to the first reflection point 5, the distance d ₂ from the first reflection point 5 to the second reflection point 6, the second reflection point 6 If the sum (d ₁ + d ₂ + d ₃ ) of the distance d ₃ to the immediately preceding carrier V ′ exceeds a fixed value (about 3 m in the present embodiment), the rear carrier V is
Drive at the same speed. The above sum (d ₁ + d ₂ +
If d ₃ ) is equal to or less than a certain value, the rear carrier V decelerates or stops. The transport vehicle V ′ immediately before travels as it is, and when the distance between two consecutive transport vehicles V and V ′ exceeds a certain value, the rear transport vehicle V starts to travel again.

As described above, the light L projected from the optical sensor device 1 of each transport vehicle V is reflected a plurality of times by the reflecting surface 3a of the reflecting plate 3, and is bent in the bending direction of the reflecting plate 3 (ie, the rail). R
(Curved direction). Thus, each transport vehicle V is just before 'is, even if traveling any position in the curved portion R ₁ in the rails R, itself and just before the transport vehicle V' transport vehicle V of detecting the distance between the it can. Since the traveling speed of the succeeding carrier V is controlled by this distance, collision between the two carriers V and V ′ is prevented. The trajectories of the projected light L and the reflected light L ′ always exist inside the reflection plate 3. Therefore, the curved portion R _{1 of the} rail R
Is present near the wall surface W, the light L does not detect the wall surface W. Furthermore, an obstacle (for example, a worker when a worker enters) inside the reflection plate 3 can be detected.

Next, a collision prevention device A2 according to a _second embodiment will be described. As shown in FIG. 5, the collision prevention device A ₂ in this embodiment, flat plate-shaped pair of each of the reflection plates 7a, 7b
And on the outside of the curved portion R ₁ of the rail R, in which was placed in the normal direction at right angles with the rail R. Rear carrier V
Is reflected by the first reflector 7a at a substantially right angle, travels straight, and is further reflected by the second reflector 7b at a substantially right angle. In the case of this embodiment, it is possible to detect the distance from the transport vehicle V ′ immediately before traveling on a relatively distant portion (the linear portion R _{2 of the} rail R) beyond the curved portion R ₁ of the rail R. Further, there is an advantage that the pair of reflectors 7a and 7b can be easily installed.

The collision preventing device A of the first embodiment described above.
_1, curved portions R ₁ of the rail R is semicircular, reflector 3 and correspondingly also the case for semi-circular. However, like the collision prevention device A ₃ of the third embodiment shown in FIG.
Rail curved portions R ₁ of R is quarter circle arc, curve section R
_{Even if} the traveling direction of the transport vehicle V is changed by 90 degrees before and after ₁ , the reflector 8 can be attached.
The shape of the reflecting plate 8 in this case is a quarter circle arc corresponding to the curved portion R ₁ of the rail R, mounted on the outside of the curved portion R ₁ of the rail R. Further, a fourth way of anti-collision device A ₄ embodiment, forms a right angle to install a flat plate-shaped reflection plate 9 in the normal direction of the curved portion R ₁ of the rail R shown in Figure 7 No problem.

In this specification, the case where the reflection plate 3 is a stainless plate has been described. However, as long as the reflecting surface 3a is a mirror surface capable of reflecting the light L, any material may be used.

In this specification, a case has been described in which each transport vehicle V runs over a rail R. However, a configuration in which each transport vehicle V travels while suspended on the rail R or a configuration in which the transport vehicles V travel on the floor surface may be used.

[0025]

According to the present invention, there is provided a carrier collision preventing apparatus,
In a rail transport device in which a number of transport vehicles are guided by rails and run in a row at predetermined intervals, the distance between two transport vehicles that travel on a curved portion of a rail before and after can be detected. By reducing or stopping the traveling speed of the rear carrier in accordance with the distance, the carrier can be prevented from colliding with the immediately preceding carrier at the curved portion of the rail.

[Brief description of the drawings]

FIG. 1 is a plan view of a collision prevention device A1 according to a _first embodiment of the present invention.

FIG. 2 is a side sectional view of the same.

FIG. 3 is a perspective view of the same.

FIG. 4 is a graph showing the control of the traveling speed of the rear carrier V according to the distance from the immediately preceding carrier V ′.

FIG. 5 is a plan view of a collision prevention device A2 according to a _second embodiment of the present invention.

FIG. 6 is a plan view of a collision prevention device A3 according to a _third embodiment of the present invention.

7 is a plan view of the anti-collision device A ₄ of the fourth embodiment of the present invention.

FIG. 8 is a schematic plan view of the rail transport device E.

9 transport vehicle V is, the curve portion R ₁ of the rail R,
FIG. 4 is a plan view illustrating a state where a wall surface W is detected.

FIG. 10 is a plan view of a conventional collision prevention device A '.

[Explanation of symbols]

A _{1 to} A ₄ : collision prevention device d _{1 to} d ₃ : distance E: rail transport device L, L ′: light V, V ′: transport vehicle R: rail R ₁ : curved portion 1: optical sensor device 3, 7a , 7b, 8,9 ： Reflector

Claims (4)

[Claims] 1. A rail transport device in which a number of transport vehicles are guided along a rail and run continuously at a predetermined interval. Each of the transport vehicles has an optical sensor for detecting a distance between itself and the immediately preceding transport vehicle. The device is installed, and between two successive vehicles, the light emitted from the optical sensor device of the rear vehicle is applied to the immediately preceding vehicle to detect the distance between the two vehicles. When the distance becomes equal to or less than a predetermined value, a device for decelerating or stopping the rear carrier to prevent collision between the two carriers, outside the curved portion of the rail, substantially along the rail. By installing a reflector, by reflecting the light emitted from the optical sensor device of the rear carrier by the reflector, hitting the curved portion of the rail to the carrier immediately before traveling,
An apparatus for preventing collision of a transport vehicle in a rail transport device, wherein a distance between two transport vehicles traveling on a curved portion of a rail before and after a curved line is detectable. 2. The apparatus according to claim 1, wherein the reflectors are continuously mounted. 3. The curved part of the rail has a semicircular shape,
Before and after the curved portion, the traveling direction of the carrier is 180 °
The collision prevention device for a transport vehicle in the rail transport device according to claim 1, wherein the device is switched. 4. A curved portion of the rail is formed in a quarter arc shape, and before and after the curved portion, the traveling direction of the carrier is 90 °.
3. The collision preventing device for a carrier in a rail carrier according to claim 1, wherein the carrier is turned.