JPS638067A - Safety device for trackless trolley car - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Objective of the Invention 1 (Field of Industrial Application) The present invention relates to a safety device for a trackless automatic guided vehicle (hereinafter referred to as a trackless vehicle).

(Prior Art) Trackless vehicles are used in factory automation installations, for example, to transport parts or products from a parts shop to an assembly shop or from an assembly shop to a warehouse. The path for these trackless vehicles is generally used as a road for people to pass, and is narrow, so there is often no space for safety fences to avoid contact with surrounding equipment. For this reason, if a trackless vehicle malfunctions, it may collide with people or tangible objects such as pond equipment, which is dangerous, and it is therefore required to stop the vehicle safely. However, if an abnormality occurs in the control system while the trackless vehicle is traveling at a particularly high speed, the trackless vehicle itself may spin, which is extremely dangerous since it is not traveling on the route.

For example, as shown in FIG. 4, a two-axis running steering control vehicle has independent driving wheels 2a, 2b on the left and right sides of the central part of the trackless vehicle body 1, and casters (driven wheels) 4a, 4b at the front and rear in the direction of movement. In this case, left and right independent geared motors (hereinafter simply referred to as motors) 3a and 3b rotate in a well-balanced manner to move straight, and if motor 3a
When the rotation becomes faster, the vehicle turns to the right in the direction of travel, and in the opposite case, it turns to the left.

(Problems to be Solved by the Invention) As described above, since a differential effect occurs due to the difference in rotation between the motors 3a and 3b, the vehicle may collide with a side tangible object rather than a front tangible object in the traveling direction. This is because, as shown in Fig. 5, the passage width of the trackless vehicle body 1 is generally narrow, and the distance between the side surface of the trackless vehicle body 1 and the tangible object on the ground is 20 mm.
0 to 300 #111 or where the passage width is only wide enough for a person to pass through, the trajectory 21 of the side tip of the trackless vehicle body 1 in this case is smaller than the center trajectory 22 of the trackless vehicle body 1. It collides with the wall 5 of the ground equipment at a flying distance of, for example, about 400 to 500 #1. In the case of an optically guided trackless vehicle, even if the derailment device detects that the trackless vehicle body 1 has come off the reflective tape on the traveling route 6 and applies the brakes to the trackless vehicle body 1 to stop the trackless vehicle, the trackless vehicle When the main body 1 is traveling at a high speed of about 50 TrL/1n, and even if the vehicle is a trackless vehicle with a carrying load of 500 liters or less, the distance required to complete the stop is 1 to 1.
5m is required. Therefore, if an abnormality occurs in the control system, it is necessary to control the two motors 3a and 3b from a separate system so that the differential effect does not occur.

Therefore, the present invention provides a safety device that stops the trackless vehicle to prevent it from colliding with tangible objects such as people or obstacles even if the trackless vehicle derails due to a failure in the control system and causes a spin phenomenon. The purpose is to

[Structure of the Invention] (Means for Solving the Problems) In order to achieve the above object, the present invention is constructed as follows. In other words, in a trackless vehicle that has a plurality of drive wheels and is driven by individual motors, the trackless vehicle travels on a trackless route using optical, electromagnetic, gyro, or other guidance methods. A mechanical brake that stops the trackless vehicle and a tangible object such as a person or an obstacle present on the side of the trackless vehicle body in the running direction are detected, and the distance between this tangible object and the side surface of the trackless vehicle body is less than or equal to the set distance. The device comprises a distance sensor that produces an output when the distance sensor generates an output, and a means for applying a mechanical brake while giving a stop command to a control circuit that controls the speed of the motor when the distance sensor generates an output.

(Function) By configuring as described above, the trackless vehicle main body can be gradually decelerated and stopped without colliding with tangible objects such as people or obstacles.

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings. Figure 1 is a diagram showing the relative distance between the corners of the trackless vehicle body and the side wall of the running road, Figure 2 is a diagram showing the arrangement of the main components of the safety devices installed on the trackless vehicle body, and Figure 3 1 is a block diagram showing an embodiment of a safety device for a trackless vehicle according to the present invention.

In Figures 1 and 2, 2a is a right drive wheel, 2b is a right drive wheel, 3a is a geared motor for the left drive wheel (hereinafter simply referred to as the motor), and 3b is a geared motor for the right drive wheel (hereinafter simply referred to as the motor). 4a is a front caster, 4b is a rear caster, 5a is an obstacle such as the left side wall, 5b is an obstacle such as the right side wall, 6 is a running route consisting of reflective tape or electromagnetic line, etc., 7a is the motor 3a. 7b is an encoder that detects the rotational speed of the motor 3b, 8a is a clutch brake of the motor 3a, 8b is a clutch brake of the motor 3b, and Sl is on the left rear side of the trackless vehicle body 1. The light-reflecting photoelectric sensor provided is S2, the light-reflecting photoelectric sensor provided on the left front side of the trackless vehicle body 1, S3 is the light-reflecting photoelectric sensor provided on the right rear side of the trackless vehicle body 1, and S4 is the light-reflecting photoelectric sensor provided on the right rear side of the trackless vehicle body 1. 1, and the set distance of each photoelectric sensor S1 to S4 is Lm.

This set distance is, for example, a value shorter than the minimum approach distance when a person passes by.

In FIG. 3, reference numeral 10 denotes a travel route calculation unit, which is equipped with a transportation route map and knows where the trackless vehicle itself is currently traveling, issues a speed command 10a to a speed command generation unit 11, and sends a speed command 10a to a speed command generation unit 11, Reverse command 10b,
10C are given to chopper control units 12 and 13, which will be described later, and when the trackless vehicle main body 1 is running, a forward command 10
d. Outputs a backward movement command 10e to a logic processing circuit LGC, which will be described later, and further issues a clutch brake command 10 to the clutch brakes 8a and 8b when stopping the trackless vehicle body 1.
It gives f. 14 is a route deviation amount detector;
Trackless vehicle body 1 from the center line of ground traveling route 6
This is to detect how much the difference is.

Reference numeral 15 denotes a summing point provided on the input side of the chopper control section 12, where the speed command VO from the speed command generation section 11 is
I, the amount of deviation from the route deviation amount detection section 14, and the feedback signal fl obtained by the waveform shaping of the actual speed of the driving and driving wheels 2a from the speed detection section 16 in the V/F conversion section 17 to obtain the above result. This is input to the chopper control section 12, and thereby the speed of the motor 3a can be controlled at the conduction rate determined by the chopper control section 12.

Further, numeral 19 is a summing point provided on the input side of the chopper control section 13, and the speed command (■) from the speed command generation section 11 is received. 1, the amount of deviation from the route deviation amount detection section 14, and the actual speed of the driving wheel 2b from the speed detection section 20, which are waveform-shaped by the V/F conversion section 21, resulting in a feedback signal Vt.
2 are added together and input to the chopper control section 13, so that the speed of the motor 3b can be controlled at the conduction rate determined by the chopper control section 13.

22 is an OR circuit that ORs the outputs of the photoelectric sensors 81 and 84, 23 is an OR circuit that ORs the outputs of the photoelectric sensors 82°S3, and 24 is an OR circuit that ORs the outputs of the photoelectric sensors 81 and 84; An AND circuit 25 logically ANDs the backward command 10e, an AND circuit 25 logically ANDs the reverse command 10e from the traveling route calculating section 10 and the output of the OR circuit 22, and 26 an AND circuit logically multiplying the backward command 10e from the traveling route calculating section 10. 27 is an AND circuit that ANDs the forward command 10d and the output of the OR circuit 22; 27 is an AND circuit that ANDs the forward command 10d from the traveling route calculating section 10 and the output of the OR circuit 23; 28 is the OR circuit The outputs of the circuits 22 and 23 are ORed, and this output is sent to the chopper control section 12 and 13.
29 is an OR circuit that ORs the outputs of the AND circuits 26 and 24 and outputs this output to the clutch brake 8a, and 30 is the AND circuit 27.25°. This is an OR circuit that logically sums the outputs of and outputs this output to the clutch brake 8b, and these OR circuits 22, 23, 28, 2
9.30 and AND circuits 24, 25, 26.27 constitute a logic processing circuit LGC8.

Hereinafter, the operation of the safety device for the trackless vehicle configured as described above will be explained. When the trackless vehicle main body 1 is traveling in a straight line, a speed command 10a is given from the travel route calculation unit 10 to the speed command generation unit 11, and the speed command generation unit 11 outputs the speed command ``02'' to the addition point 15i9, respectively. is input.

Further, at this addition point 15.19, the outputs ±ΔVl, ±Δ■2 from the route deviation amount detection unit 14, and the feedback signal Vrt of the actual speed from the V/F conversion unit 17.21.
, V12 are respectively input. Then, the output of the above addition point 15.19 is output to the chopper control section 12.13.
is input to the motor 3a.

The speed of 3b is increased by 1dllIl. In this state, nothing? ￥
ll When the road vehicle main body 1 deviates to the right side with respect to the traveling route 6, the speed of the left motor 3a is increased, and the speed of the right motor 3 is increased.
b is decelerated. Conversely, when the trackless vehicle main body 1 deviates to the left with respect to the traveling route 6, the left motor 3a is decelerated, and the right motor 3b is accelerated. For this reason, the trackless vehicle body 1 travels on the ground travel route 6 at the average speed of VOI and v02.

Also, when braking the trackless vehicle main body 1, the chopper control unit 12.1
3 is in braking mode, and motor 3a.

A braking current is applied to each of the terminals 3b, whereby the trackless vehicle main body 1 decelerates, and immediately before stopping, the running route calculation unit 10
A clutch brake command 10f is given to the clutch brakes 8a, 8b, and the clutch brakes 8a, 8b operate thereby to stop the trackless vehicle body 1. In this way, the trackless vehicle main body 1 is controlled to travel on the traveling route 6 both when traveling or when braking.

In such a configuration, if the speed detection section 20
For example, if the encoder 7b breaks down due to a disconnection, there will be a signal from the V/F converter 21 to the motor 3b at the summing point 19.
Since the feedback signal V(2) of the actual speed of It spins to the left by the difference in rotation speed of 3b. This situation is as shown in Figure 1,
In this case, the second
The side wall surface 5a is detected by the photoelectric sensor S2 in the figure. Since this photoelectric sensor S2 is set to a set distance Law, when the trackless vehicle main body 1 approaches closer than Lm, the photoelectric sensor S2 operates and produces an output. For this reason, the OR circuit 23
An output is generated in the AND circuit 27, and the AND condition is satisfied.
An output is generated from the OR circuit 30, the clutch brake 8b is operated, a brake is applied to the motor 3b, and the trackless vehicle main body 1 starts turning to spin to the right and away from the left side wall 5a.

As mentioned above, any one of the photoelectric sensors S1 to S4 (
In the above case, the fact that S2> is activated means that the control system has already become unstable, and the trackless vehicle main body 1 cannot run normally. Therefore, since an output is generated in either the OR circuit 23 or 22, an output is generated from the OR circuit 28, thereby stopping the operation of the chopper control section 12. is given, and it is communicated that the speed detection section 20 is out of order. As a result, the traveling route calculation section 1
0, the brake command 10f is sent to the clutch brakes 8a and 8b only when the output of the OR circuit 28 occurs.
is applied, and the motors 3a and 3b enter the braking state. As a result, the trackless vehicle main body 1 starts turning so as to spin to the right, and the photoelectric sensor S2 becomes inactive.

Then, the output from the OR circuit 23 disappears, the output from the OR circuit 28 also disappears, and the clutch brake 8a is activated by the output from the travel route calculating section 10.

8b operates, and the trackless vehicle main body 1 tries to stop suddenly. Meanwhile, since the trackless vehicle main body 1 is facing in either direction, the photoelectric sensor S2 or S4 is activated. If the photoelectric sensor S4 operates, it is because the trackless vehicle main body 1 approaches the side wall surface 5b, and at this time, the clutch brake 8a is activated by a command from the traveling route calculation unit 10.
, 8b is released, an output is generated from the OR circuit 22, 29 and the clutch brake 8b is released.
a! The trackless vehicle main body 1 operates to spin to the right. While repeating this operation sequentially, the trackless vehicle body 1 is gradually decelerated, and finally the trackless vehicle body 1 comes to a stop.

The operation described above is when the trackless vehicle main body 1 is moving forward and the charging sensor S2 operates to generate an output, but when the trackless vehicle main body 1 is moving forward and the photoelectric sensor S1 or S4 is activated, the clutch brake 8a operates, and the photoelectric sensor S
2 and S3 operate, the clutch brake 8b operates. Similarly, when the trackless vehicle main body 1 is moving backward and the photoelectric sensor S1 or S3 operates, the clutch brake 8b
operates, and when the photoelectric sensor S2 or S3 operates, the clutch brake 8a comes to operate.

By operating in this way, the trackless vehicle main body 1 does not collide with the side walls 5a, 5b or tangible objects such as people on the side. This effect is particularly effective in the case of the gyro guidance method. That is, in this case, when an abnormality occurs in the gyro system, the location of the trackless vehicle itself may become completely unknown.

Further, according to the above embodiment, a relatively simple safety device is provided separately from the drive control system of the trackless vehicle body 1, so
Increased reliability in terms of safety.

The trackless vehicle main body 1 of the embodiment described above is equipped with an ultrasonic sensor or a reflective sensor for relatively long distances in the direction of travel, and has a function of decelerating when a tangible object is detected in the direction of travel. Needless to say, the trackless vehicle main body 1 is provided with bumpers and the like on the front and rear surfaces of the trackless vehicle main body 1 so that the trackless vehicle main body 1 can safely stop while decelerating on the traveling route.

The present invention is not limited to the embodiments described above, but may be configured as follows. That is, although the photoelectric sensor provided on the side surface of the trackless vehicle body 1 in the above embodiment is capable of detecting the presence of a tangible object within a certain distance, instead of this, a photoelectric sensor provided on the side surface of the trackless vehicle body 1 is installed at the center of the trackless vehicle body 1. By providing a distance meter, which allows the distance from the side wall of the running route to be changed using the position of the trackless vehicle body 1 as a parameter, it is possible to reduce the amount of vibration of the trackless vehicle body 1 more quickly and safely than in the above embodiment. You can stop by reducing the amount. In addition, although the above embodiment is based on a two-axis travel steering system, it can be implemented in the same way even with an omnidirectional trackless vehicle. In this case, if the steering gauge is active, not only the brakes but also the By performing steering control using photoelectric sensors S1 to S4, the vehicle can be stopped safely.

[Effects of the Invention] The present invention described above has a plurality of drive wheels, and these are driven by individual motors. In a trackless vehicle, a mechanical brake is provided to stop the running of the trackless vehicle body, and a tangible object such as a person or an obstacle present on the side of the trackless vehicle body in the running direction is detected, and a mechanical brake is installed to stop the running of the trackless vehicle body. A distance sensor that generates an output when the distance to the side surface becomes less than the set distance, and when an output is generated from this distance sensor, a stop command is given to the control circuit that controls the speed of the motor, and the mechanical brake is applied. The trackless vehicle is constructed with a hand R that allows the trackless vehicle to stop, so that even if the trackless vehicle derails due to a failure in the control system and spins, the trackless vehicle will not collide with tangible objects such as people or obstacles. Safety equipment can be provided.

[Brief explanation of the drawing]

Figure 1 is a diagram showing the relative distance between the corners of the trackless vehicle body and the side wall of the running road, Figure 2 is a diagram showing the arrangement of the main components of the safety devices installed on the trackless vehicle body, and Figure 3 The figure is a block diagram showing an embodiment of the safety device for a trackless vehicle according to the present invention, and FIGS. 4 and 5 are both for explaining the configuration of a conventional trackless vehicle. It is a wheel arrangement diagram of the main body, and the fifth factor is a diagram showing the relationship between the trackless vehicle main body and tangible objects such as side walls on the sides of the traveling route. 1... Trackless vehicle body, 2a, 2b... Drive wheel, 3
a. 3b... Geared motor, 4a, 4b... Caster, 5a, 5b... Side wall, 6... Traveling route, 7a,
7b... Encoder, 8a, 8b... Clutch brake, S1-S4... Photoelectric sensor, 9... Control II device, 10... Driving route calculation unit, 11... Speed command generation unit, 12゜13 Chopper control section・, 14・・
・Root deviation detection section, 15.19...Addition point, 16.20...Speed detection section, 17.21...V/
F conversion section, 22.23°28.29.30...OR circuit, 24,25.26°27...AND circuit. Applicant's agent Patent attorney Takehiko Suzue @Figure 1 Figure 4

Claims (2)

[Claims] (1) In a trackless vehicle that has a plurality of drive wheels, each of which is driven by an individual motor, the trackless vehicle travels on a trackless route using optical, electromagnetic, gyro, or other guidance methods. A mechanical brake that stops running and a tangible object such as a person or an obstacle present on the side of the trackless vehicle body in the running direction are detected, and the distance between this tangible object and the side surface of the trackless vehicle body is less than or equal to the set distance. A safety device for a trackless vehicle comprising a distance sensor that generates an output when the distance sensor generates an output, and means that applies a stop command to a control circuit that controls the speed of the motor and applies the mechanical brake when the distance sensor generates an output. . (2) The safety device for a trackless vehicle according to claim 1, wherein the set distance is a changeable value.