JPS6347210A - Travel control method for introducing and delivering travel crane or the like - Google Patents

Abstract

PURPOSE:To simplify a shift device, by running the shift device at a predetermined high speed to a position having a predetermined distance before a desired stopping position, and thereafter by controlling a running pattern composed of a deceleration by a predetermined decelerating degree and a travel at a predetermined low speed, in dependence upon time. CONSTITUTION:A shift device is made to run at a predetermined high speed on a running path on which stopping positions 1-9 are arranged at predetermined intervals, and is decelerated by a predetermined decelerating degree from a specified position, and the number of the positions Nd until a predetermined low speed is attained, is counted and stored in memory. The shift device running at the predetermined low speed is stopped at a first arriving position to measure and store a required time therefor, and a delayed time for reducing the required time to a necessary minimum predetermined time is computed from the ratio between the predetermined high and low speeds. During actual working, the shift device is made to run at a high speed until the delayed time elapses after it has passed a stopping position just before Nd+1 from a desired stopping position, and after the predetermined delayed time elapses, deceleration and running at low speed are carried out to make the shift device stop at the desired stopping position.

Description

Detailed Description of the Invention (Industrial Field of Application) The present invention is applicable to mobile cranes in which stopping positions are set at fixed intervals during the traveling route, such as traveling cranes for loading and unloading used in automated warehouses. The present invention relates to a traveling control method for stopping a device at a desired stopping position.

(Prior art and its problems) In general, the running pattern of this type of moving device is to run at high speed until a certain distance before the target stopping position, and then decelerate to a certain low speed at a certain deceleration point when it reaches the deceleration point. This is a pattern in which the vehicle travels at a constant low speed to the target stop position and then stops, but the problem in control is how to set the deceleration point.

That is, in the driving pattern, the preset high speed, low speed, and deceleration are determined to be optimal values in consideration of safety and efficiency, so they cannot be changed during actual driving control. Can not. Further, the running time at the constant low speed must be the minimum time necessary to obtain a stable running state so as not to adversely affect subsequent stop control.

Therefore, in the conventional general method of setting a stop position a certain number of points before the target stop position as the deceleration point, the distance traveled at a constant low speed after deceleration is compared with the minimum required distance due to the relationship between the stop position pitches. This may result in a very long process, making it impossible to improve work efficiency. In order to solve these problems, the pulses of the pulse encoder that are linked to the movement of the moving device are counted, the current address of the moving device is determined, and this is compared with the destination address corresponding to the target stop position to determine the difference between the two. One type of pulse encoder, which uses the deceleration point when the deceleration point reaches a certain level, has also been put into practical use, but it has the disadvantage of being expensive because it requires a pulse encoder and associated mechanical and electrical parts. .

(Means for Solving the Problems) The present invention proposes a traveling control method that can solve the conventional problems as described above, and its feature is that the stop positions are set at regular intervals. The moving device is caused to travel at a constant high speed on a specified travel route, decelerated at a constant deceleration from a specific stop position, and counting and storing the number of stop positions Nd that occur in i1m until reaching a constant low speed, The moving device traveling at a constant low speed is controlled to stop at the first stop position it reaches, the time required while traveling at the constant low speed is measured and stored, and the required time is kept to a minimum necessary. Calculating the delay time to shorten the time to a constant time from the speed ratio of the constant high speed and the constant low speed,
During actual operation of the moving device, the N
After passing the stop position d+1 before, the vehicle is run at a constant high speed until the delay time elapses, and after the delay time VA has elapsed, the vehicle is decelerated by a constant deceleration and travels at a constant low speed, and then comes to a desired stop. The point is to stop at a certain position.

(Embodiment) An embodiment of the present invention will be described below based on the attached illustrative drawings. In FIG. The vehicle travels while being guided by upper and lower guide rails 3.4 arranged at the top and bottom. This crane 1 is equipped with an elevating carriage 6 equipped with a load transfer fork 5, and a load handling receiver installed adjacent to the home position at one end of the crane travel path is used to store each load on a platform 7 and a shelf 2. It is possible to carry out loading and unloading work between the compartment 2a and the compartment 2a. Reference numeral 8 denotes a travel drive device for the crane 1, which is composed of a drive wheel 9, a motor 10 for driving the drive wheel, a braking means, and the like. Reference numeral 11 denotes an elevating and lowering drive device for the elevating carriage 6, and 12 represents an egress/retreat drive device for the fork 5.

As shown in FIGS. 2 and 3, a home position 11.0 is installed at each crane stop position, that is, a cargo receiving platform 7 is installed beside the travel path of the crane 1. A detection plate 13 having an appropriate length in the crane traveling direction is provided corresponding to each pay position (from the first pay to the fifth pay in FIG. 2) of the crane 1 and the shelf 2. The front detector 14 and the rear detector 1 are arranged at intervals that allow simultaneous detection of both the front and rear ends of the detected object vi 13 at the stop position when it stops at the stop position.
5 is attached.

The arithmetic/storage/control means 16 shown in FIG. 2 is composed of a microcomputer and necessary accessory equipment, and includes detection signals 14a, 15a of the detectors +4.15, and both detectors 14.15. ? 5 are both turned ON, a device detection signal 17a constituted by an AND gate 17, a clock pulse 18 supplied from a clock pulse generating means, a destination command 19, and a current speed value supplied from the crane traveling drive device 8. 20 etc. as inputs, and a control signal 21 that controls the crane traveling drive device 8 based on these inputs.
This outputs the following.

Next, a learning method will be explained.Here, as the traveling speed of the crane 1, each speed of high speed, medium high speed, medium low speed, and low speed is set and stored in advance in the calculation/memory/control means 16. The clock pulse 18 is emitted at a rate of, for example, one pulse every 20 seconds, and is counted as a time count value, and the output time of the fixed position detection signal 17a is set to the time of arrival at each stop position or the time of arrival at each stop position. The current address of the crane 1 is determined by the stop position address unique to each stop position by counting the fixed position detection signal +7a as the time when the crane passes the stop position and adding it when the crane is moving forward and subtracting it when it is moving backward.

[Learning 1] First, move crane 1 to a preset medium to low speed (e.g. 10i
10+in), advance from home position H, P to home position 0
．． P (5th pay in Figure 3), and during this time the 3rd
As shown in the figure, the front detection signal 14a (or the rear detection signal 1
The time count values at the rise and fall of 5a) are stored, and the distances between each stop position, Lf, L3, . The travel time required between each stop position T, , T, , T3, ...... is proportional to...
Calculate and store. Crane 1 is at forward origin o, p
When reaching <the fifth pay in FIG. 3), the crane 1 is returned to the home positions H and P [Learning 2] (1) The crane 1 is driven to the home position of the first pay and stopped. Then, as shown in FIG. 4, the crane 1 is accelerated forward at a constant acceleration (e.g., 0.03 g), and the current crane speed value 20 is set at a preset high speed (e.g., 6 g).
The number of pays (number of stopped positions) Nu passed until reaching 3m/lll1n) is determined by counting the fixed position detection signal 17a and stored (Nu=2 in FIG. 4).

(2) When the crane 1 reaches a certain high speed, the speed is controlled to maintain the high speed and continues forward travel, but after the crane 1 reaches the certain high speed, for a certain period of time,
For example, it is assumed that the traveling speed of the crane 1 becomes stable at the constant high speed after 0.43 elapses, and after this 0.43 elapses, the crane moves from the stop position (the 4th hey in FIG. 4) to which the crane first passes. The time Th required at a constant high speed to reach the stop position of the pay destination (the 6th pay in FIG. 4) is measured and stored. This required time Th can be determined by starting the counting of the clock pulses 18 from the time when the fourth pay passes.
This is the time count value when the 6th pay, which is 2 bays ahead, is reached. Of course, when counting the clock pulses 18 all the time, the required time Th is calculated by calculating the difference between the time count value when the fourth pay passes and the time count value when the sixth pay is reached. You can also do that.

(3) From the stop position (6th pay in Fig. 4) where the travel for measuring the required time Th has ended, the crane 1 is moved at a preset medium to low speed (for example, 10 m/s) at a constant deceleration.
11 inch), and the number of pays (number of stopped positions) Nd passed during this time is determined by counting the fixed position detection signal 17a and stored (Nd-2 in FIG. 4).

(4) The time required to run at the medium-low speed, that is, the minimum time necessary to obtain a stable medium-low speed driving condition so as not to adversely affect subsequent stop control, is set to, for example, 2S. Then, from the time when the crane 1 travels at a medium to low speed and after 2S jβ, the crane 1 reaches the first stop position (the 9th hey in Fig. 4) until the point where the stop control is executed to stop the crane 1. In other words, the time required while traveling at the medium-low speed is calculated as follows:
1! Slurp.

The stop control in this embodiment is such that when the front detector 14 detects the detection target plate 13 at the stop position and the front detection signal 14a rises, the speed is decelerated from medium to low speed to a preset low speed, and then the plate is at the fixed position. Detection signal? This is done by releasing the drive and braking at the time when the signal 7a is output, and this stop control causes the crane 1 to stop within the area where the home position detection signal +7a is output.

Therefore, the required time The is the time required from the time when the speed becomes medium-low to the time when the pre-detection signal 14a rises after 25 elapses, and counting of clock pulses 18 is started from the time when the speed becomes medium-low. In this case, the time count value is the time count value at the rise of the previous detection signal 14a. Of course, as explained above, when counting the clock pulses 18 all the time, the difference between the time count value at the time when the speed becomes medium to low and the time count value at the rise of the pre-detection signal 14a is calculated. The required time The may be determined by calculation.

Learning 2 is completed above, and the following data is obtained by this learning.

■On the route along shelf 2, it passes through two bays from a stopped state until it reaches a certain high speed.

- The time required for traveling two bays at a constant high speed is Th.

- The number of payouts (Nd+1) required until the constant high speed stops is 3 bays.

■Time required from starting to drive at medium to low speed until stop control (
creep time) is longer than the minimum necessary time of 2 seconds.

■It is not possible to run at high speed unless there is a travel distance of 6 bays or more.

[Learning 3] Although the details are omitted, instead of the high speed driving in Learning 2, as shown in Fig.
), the following data can be obtained by performing learning based on driving in the same manner as learning 2 above.

■On the route along shelf 2, the vehicle passes through one bay from a stopped state to a constant medium-high speed.

■-The time required for running two bays at a constant medium to high speed is Tm.

■-The number of payouts required to stop at a constant medium-high speed is 2 bays.

■Time required from starting to drive at medium to low speed until stop control (
creep time) is Tsc longer than the minimum necessary time of 2 seconds.

■It is not possible to run at medium and high speeds unless there is a travel distance of 4 bays or more.

Next, the control method during actual operation will be explained. The crane traveling drive device 8 is controlled based on a command, a deceleration and stop command, a deceleration command from a medium-low speed to a low speed, and a braking command, so that the crane travels and stops in a predetermined pattern. Further, the acceleration stop command and deceleration stop command are output based on a comparison calculation between the current speed value 20 supplied from the crane travel drive device 8 and a preset speed value.

(5) The calculation/storage/control means 16 sends a destination command 19
When received, the current address of the crane 1 given by the addition/subtraction count of the fixed position detection signal 17a is compared with the set destination stop position address, and the traveling direction of the crane 1 is determined by determining the size of both addresses. At the same time, the moving distance of the crane 1 is calculated based on the difference between the two addresses, and depending on this moving distance (number of pays), it is selected whether to run at high speed, medium-high speed, or medium-low speed.

For example, if the current address of crane 1 is the 1st pay and the destination stop position address specified by the destination command 19 is the 8th pay, high-speed travel is selected from learning 2-■ because the crane movement distance is 7 pays. be done.

tb+ The crane traveling drive device 8 is activated by the start command and traveling direction command supplied to the crane travel drive device 8, and the crane 1 that has started from the first pay toward the eighth pay is accelerated and reaches the set high speed. When this is reached, an acceleration stop command is output and the vehicle switches to running at a constant high speed. During this time, it is confirmed that two bays have been passed before reaching a constant high speed according to learning 2-■. If the number of passing pays is not 2 pays, it is treated as a failure due to an abnormal running speed.

(Cl learning 2-■ to destination stop position address (8th pay)
The vehicle is run at the set high speed until it reaches a stop position (fifth pay) three bays before.

Since the creep time The of +dl learning 2-■ is longer than the minimum necessary time 2S, this creep time The
is 2s (converted to time count value: 2÷0.02
= 100), so as shown in Figure 6, if the creep time obtained when the 5th pay is detected and the speed is decelerated immediately is Tx, then the time count value of Tx is 100. After detecting the fifth pay, it is sufficient to delay the speed by the delay time Ty and decelerate the speed.

Here, if the creep time The is proportional to the travel distance from the start of deceleration to the stop, that is, the travel time at medium and low speeds (Tq + Te + Tw = Tvq) obtained by learning 1, then The = k X T, q. A constant k is obtained. If this constant is constant in the system, then TxxkxT6s also holds true. Here, T is the travel time from the 5th pay to the 8th pay at medium to low speed (T h + T y +
T m =Tit), and k = T he + T
? q, so Tx=Thc+Tqq×The.In order to set the time count value of this Tx to 100, it is sufficient to delay and decelerate by 100 (Tx 100=The+TywXT6a). However, since this time count value is data when traveling at medium and low speeds, the speed ratio between high speed and medium and low speed must be taken into account. Using the time Th and the travel time T,+”r, required for traveling at medium and low speeds in the same section obtained in learning 1, the delay time TV is calculated.
When calculating, Ty = (The+Tt*XT, -100) x
(T5+74)+Th.

Therefore, after the crane 1 reaches the fifth pay, the high-speed traveling is continued until the delay time (time count value) Ty determined by the above calculation has elapsed, and when the delay time Ty has elapsed, a deceleration start command is issued. Crane traveling drive device 8
to reduce speed. Crane 1 as shown in Figure 6
When the traveling speed of the crane reaches the set medium-low speed, a deceleration and stop command is supplied to the crane traveling drive device 8, and the crane 1 travels at the set medium-low speed, but the medium-low speed is maintained for the minimum necessary 2S. The front detection signal 14a is output when the crane 1 travels at the desired destination stop position, and the 1tilf 473 signal 21 for predetermined stop control is supplied to the crane traveling drive device 8. It will stop at that point.

The delay control starts counting the clock pulses 18 from the time when the fixed position detection signal 17a of the fifth pay is output,
When the time count value reaches a value corresponding to the delay time Ty, a deceleration start command is output, or the time count value at the time when the fixed position detection signal 17a of the fifth pay is output is set to the delay time Ty. The deceleration control time count value may be obtained by adding the corresponding time count values, and control may be performed so that the deceleration start command is output when the actual time count value becomes equal to the deceleration control time count value.

If the tel or destination stop position address is the 6th pay, the crane moving distance is 5 pays, so medium-high speed travel is selected from learning 3-■. In this case as well, based on the data from Learning 3-■ to After a predetermined delay time, the vehicle is decelerated to a medium-low speed, and after running at a medium-low speed for about 2 seconds, stop control is performed and the vehicle reaches the destination stop position, which is the sixth stop.
Stop at pay.

If the destination stop position address is the third pay, the crane moving distance is 2 pays, so neither learning 2-■ nor learning 3-■ applies, so medium-low speed travel is selected. In this case, there is no need to perform deceleration control as described above.

In addition, in a system where the distance between each stop position is constant, the calculation of the creep time Tx using the constant k is omitted, and the time count value 100 equivalent to 2S is directly subtracted from the creep time Thc, and this is multiplied by the speed ratio. delay time Ty
can be found.

In this case, it is desirable to calculate and store the delay time Ty in advance.

(Operations and Effects of the Invention) As described above, according to the travel control method of the present invention, the moving device is moved at a constant high speed (high speed or medium-high speed in the embodiment) until it reaches a position a predetermined distance from the target stop position. It can be controlled using a running pattern in which the vehicle is run, then decelerated by a constant deceleration, and then driven at a constant low speed (medium-low speed in the example) and then stopped at the target stop position. Because it is a method, it can be implemented using only the microcomputer and its attached equipment, which are necessary for various conventional control methods, and the cost is reduced because a pulse encoder and various accompanying parts are not required. It is possible to aim for

Moreover, as with the one-way pulse encoder type, even if the stop position pinch is large, the deceleration start timing is controlled so that the low-speed running time immediately before stop control is always the minimum necessary.
Work efficiency can be increased.

[Brief explanation of the drawing]

Figure 1 is an elevation view of the automated warehouse, Figure 2 is a block diagram explaining the configuration of the control means, Figures 3 to 5 are illustrations of the learning method, and Figure 6 is the control method during actual operation. FIG. 1... Traveling crane for loading and unloading, 2... Shelf, 8...
Crane travel drive device, 13...detected plate, 14.1
5... Pair of front and rear detectors, 16... Arithmetic/memory/control means, 18... Clock pulse. Figure 1 Figure 2 Figure 5 / Miya 4 Figure / σ Figure

Claims (1)

[Claims] A moving device that travels at a constant high speed along a travel route with stopping positions set at regular intervals, and is decelerated at a constant deceleration from a specific stopping position until reaching a constant low speed. counting and storing a number Nd, controlling the moving device traveling at the constant low speed to stop at the first stop position it reaches, and measuring and storing the time required while traveling at the constant low speed; A delay time for shortening this required time to the minimum necessary constant time is calculated from the speed ratio of the constant high speed and the constant low speed, and when the moving device is in actual operation, from the target stop position to the Nd+1
After passing the stop position in front of the vehicle, the vehicle is caused to travel at a constant high speed until the delay time elapses, and after the delay time has elapsed, the vehicle is decelerated by a constant deceleration and travels at a constant low speed until the target stop position is reached. A traveling control method for a traveling crane for loading and unloading a warehouse, etc., characterized by stopping the crane.