JPS646482B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an automatic fixed position stopping device for a trolley, and in particular, an automatic fixed position stop device for automatically stopping a trolley so that cargo loaded on the trolley (hereinafter referred to as a work) stops at a predetermined position. This relates to a stopping device, and specifically, it is mainly intended for bogies that run on tracks installed in factory premises.

Conventionally, in order to stop the trolley so that the workpiece loaded on the trolley stops at a predetermined position, the first step is to
After the workpieces are correctly positioned and loaded on the platform of the truck and the truck is driven, it is necessary to stop the truck itself at a predetermined position, which requires a lot of work.

The present invention provides an automatic fixed position stop that does not necessarily require correct positioning of the workpiece on the cart, and moreover, makes it possible to automatically stop the cart so that the stop position of the workpiece is within an error tolerance range. The purpose is to provide a device.

Next, an embodiment in which the present invention is applied to automatically stopping a molten steel truck in a steel mill will be explained in detail with reference to the drawings. 3 is a molten steel truck (hereinafter simply referred to as a truck) that travels, and 3 is a molten steel ladle (hereinafter simply referred to as a ladle) loaded on the truck 2.

Now, A and B are laser beam position detectors (hereinafter referred to as the first switch and B as the second switch) installed on the sides of the track 1 at the height of the upper edge of the pot 3, When moving on the orbit 1 in the direction of the arrow Q shown in the figure, the upper edge of the pot 3 blocks those laser beams, detects the position of the pot 3, and automatically issues the commands described below. It is formed.

Hereinafter, for convenience of explanation, the direction in which the trolley 2 moves, that is, the left side as viewed in the figure, will be referred to as the front, and the opposite direction will be referred to as the rear.

In the figure, P is the planned stopping point at the center of pot 3, and C
is a reference point set at a position behind the scheduled stopping point P by a distance equal to the radius R of the outer circumference of the upper edge of the pot 3.

Accordingly, the first switch A and the second switch B are installed at a first limit point and a second limit point, respectively, which are spaced backward and forward by an error tolerance α with respect to the reference point C as the center.

Note that in this embodiment, the above-mentioned error tolerance value α is set to 25 mm.

Now, in FIG. 1, 4 is a junction box attached to the rear end of the running path of the truck 2, 5 is a cable reel mounted on the truck 2, and the rear end of the cable 6 is wound around the reel 5. is connected to the connection box. 7
8 is a brake attached to the motor 7, and 9 is a pulse generator attached to the axle of the truck 2, which is activated by the rotation of the wheels. The pulse is generated every time the trolley 2 moves by a unit distance. 10 is a control panel, 11 is a counter, and the counter 11 includes a distance counter L, an initial count number setting dial L ₁ , a deceleration command count number setting dial L ₂ , and a brake command count number setting dial L ₃ . In each case, the number of pulse counts required to control the trolley is
It is formed so that it can be set in advance according to the scheduled stop position of the truck, running resistance of the truck, brake characteristics, etc. Next, to explain the settings in detail, _L1 contains the pulses that should be counted from the position where the laser beam of the first switch A is blocked by the front end of the pot 3 to the stop position of the cart. Set the number l ₁ , L ₂ set the number of pulses l ₂ that should be counted from the position where the deceleration command is issued to the bogie until the bogie stops, and L ₃ The number of pulses _l3 to be counted from the position where the stop brake command is issued to the stop position of the truck is set.

Next, the automatic stop operation of the truck by the above-mentioned device will be specifically explained in detail with reference to FIGS. Run the pot 3 as shown in Figure 2 B.
When the laser beam of the first switch A is blocked by the front end of the upper edge, the pulses emitted from the pulse generator 9 are integrated by the distance counter L, and when the number of pulses reaches l ₁ - l ₂ , the pulse is applied to the brake 8. A deceleration command is issued, the deceleration brake is applied, and the traveling of the bogie is decelerated. Then, when the number of pulses reaches l ₁ - l ₃ , a stop brake command is issued to the brake 8, and the brake 8 is activated to stop the bogie. let

The above control is based on counting up the pulse signal, but once it is stopped, the control switches to the following control.

That is, when the trolley 2 stops due to the above,
As shown in FIG. 2C, if the laser beam of the second switch B is blocked by the rear end of the pan 3, but the laser beam of the first switch A is not blocked, the trolley 2 will move within the allowable error range. It is confirmed that the trolley is stopped at the position, the automatic stop operation of the trolley is completed, and the next process such as unloading the pot 3 can be performed.

Furthermore, as shown in Fig. 2D, when the laser beams from the first switch A and the second switch B are not both blocked by the rear end of the pan 3, the cart goes too far forward beyond the allowable error range. When this is detected, the control panel 10 instructs the motor 7 to move backward, and the laser beam from the second switch B is cut off, thereby stopping the motor 7. However, if the laser beam of the first switch A is also blocked by the rear end of the pot 3 at this stop position, the trolley 2
It is detected that the motor has gone too far backwards beyond the allowable error range, and a forward rotation command is given to the motor 7, and the motor 7 is stopped when the laser beam of the first switch B is no longer blocked. That is,
The trolley moves back and forth in small increments in the manner described above and stops at a point within the allowable error range.

Next _, a specific example of setting the number of pulses to the counter ₁₁ described above is as follows. Match with point P. At this time, the displayed value L of the counter is 0.
If not, correct the value of l ₁ above by that displayed value. However, when L is positive, correction is made so that the absolute value of l ₁ becomes larger.

(2) Set the deceleration command count number _l2 to _L2 .

(3) Brake command count number l ₃ for stopping at L ₃
Set.

(4) Perform automatic operation and check whether it stops within an error range of ±25 mm. When stopped within the error range, the laser beam of the first switch A is passed, and the laser beam of the second switch B is blocked. When the stop position is outside the range of ±25 mm, the displayed value of distance counter L at the time of stop is l.
Just correct the _l3 dial value. However, when l is positive, the absolute value of l ₃ is increased.

Now, the correction due to changes in wheel diameter is based on the above (1) and
(4), and in normal correction dial L ₂
Do not change the setting value.

In addition, in this embodiment, when changing the scheduled stopping position of the vehicle or changing the target vehicle, simply A, B2
All you have to do is change the setting position of each switch and correct the setting of the distance counter.

In the above-described embodiments, a laser beam position detector is used as an example of the optical position detector, but a photoelectric position detector may also be used.

The device of the present invention moves the truck toward a scheduled stop position, causes the pulse generator to emit a pulse, and detects that the front end of the cargo blocks the detection beam of the first optical position detector. When the preset number of pulses has been counted up, the deceleration brake is applied to decelerate the trolley to make it crawl, and then the preset number of pulses is counted again. When the truck is lifted up, the stop brake is applied to position the rear end of the cargo between the first optical position detector and the second optical position detector to stop the truck, and when the truck has stopped, When both the detection beams of the first optical position detector and the second optical position detector are blocked by the rear end of the cargo, the truck is moved forward;
Further, when both of the light beams are not blocked, the bogie is moved backward to stop the bogie at a fixed position.In the present invention, the bogie is used for detecting the position of the bogie moving on the track. The structure is extremely simple as it uses only two detectors: a first optical position detector and a second optical position detector installed in front of it with a tolerance interval for the stop position. It's easy. In addition, these two detectors can issue a deceleration start command to the running trolley and an inching forward/backward command to correct the stop position. Furthermore, it is extremely convenient because it is sufficient to simply change the set positions of the two detectors and change the set values of the counters in response to a change in the scheduled stopping position or a change in the target vehicle. Furthermore, in the present invention, since the front and rear ends of the cargo itself loaded on the trolley are used to detect the position of the trolley, accurate movement relative to the trolley is possible when loading the cargo onto the trolley. No directional positioning is required. Therefore, the loading and unloading work of the cargo can be significantly streamlined, and the cargo can always be automatically stopped within the error tolerance range, so the effects of the present invention are extremely large.

[Brief explanation of drawings]

The figures show an embodiment in which the present invention is applied to a molten steel cart. Fig. 1 is a front view schematically showing the state in which the molten steel cart has stopped at a predetermined position without error, and Fig. 2 A to D show automatic stopping of the molten steel cart. These are plan views illustrating each stage from the start of operation to the stop, in which (a) shows the state in which the trolley is traveling toward the scheduled stop position, (b) shows the state when the count start command is issued for automatic stop operation, and (c) shows the state in which the trolley D indicates a state in which the cart has stopped at a point within the allowable error range, and D indicates a state in which the cart has stopped at a point exceeding the allowable error limit. FIG. 3 is a curve explaining the operating state of the molten steel truck, and FIG. 4 is a block diagram showing an example of truck control. 2... Molten steel truck, 3... Molten steel pot, A... First laser beam position detector, B... Second laser beam position detector, 9... Pulse generator, 10... Control panel, 1
1...Counter.

Claims (1)

[Claims] 1. A first optical position detector placed on the bogie travel track and blocked by the bogie, and a second optical position detector placed in front of it at a tolerance interval and blocked by the bogie. a pulse generator that emits a pulse every time the truck moves by a unit distance; and a distance counter that starts counting the pulses when the first optical position detector is interrupted by the truck. a control section that issues a signal to the brake when a preset number of pulses matches the number of pulses of the distance counter; and the second optical position detector, and when the first optical position detector is cut off, send a forward inching command until the first optical position detector is no longer cut off.
An automatic fixed position stopping device for a bogie, comprising a control section that issues a backward inching command until the second optical position detector is shut off when the second optical position detector is not shut off.