JPH0442318B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a crane traveling positioning method,
Specifically, the crane is stopped at the target position by detecting the stop command dog, and the running wheels of each track are controlled in relation to other running wheels, and different braking processes are applied as necessary. This relates to a method for stopping the process. This is used in the field of cranes, for example in coil yards, which run along two wide, separated tracks.

[Conventional technology]

When rolled steel strips are coiled at a steel mill and transported to the next process, the coils are first stored in a coil yard. The coil yard has many coil skids arranged in an orderly manner, and coils are brought in from the previous process and taken out to the next process using cranes installed on the yard. The crane is equipped with a girder that runs vertically over the coil skid, and a club that runs horizontally above the girder.Tongs are suspended from the club for gripping the coil, and when the pair of claws are inserted into the coil hole, , the coil can be raised and lowered and transported.

By the way, since the girder is provided so as to straddle the yard, the distance between both tracks is significantly longer than the longitudinal width of the girder. Moreover, because the club moves sideways on the girder and suspends the coil, the center of gravity of the crane itself fluctuates. In addition, a certain amount of clearance is ensured between the collar provided on the running wheel and the track. A combination of these factors often causes the girder to meander along its orbit.

Such changes in posture during movement do not pose a particular problem, but large changes in posture are not allowed in order to grasp the coil or place the coil accurately on the coil skid. In other words, in order to insert the claws of the tongs into the coil holes at the position where the girder is stopped, or to safely support the coil with the inclined support pillows placed opposite to each other, it is necessary to insert the tongs within a predetermined position range. The robot must be stopped at a certain angle, and its posture must also be within a certain tolerance range. Therefore, when operating the girder that influences the attitude of the tongs, it is desirable that the girder not only be able to stop at a predetermined position but also be able to correct the attitude before stopping.

From this point of view, there is a crane in which running wheels that move along two separate tracks are driven by electric motors that are independently provided for each track. Position detectors such as synchro resolvers are installed on both tracks to detect the crane position, and based on the current position detected by the position detectors, the necessary deceleration is required to reach the target stop position. but,
This is now done by electrically braking the motor.

According to such speed control, regardless of whether the girder is meandering or not, when the crane reaches a predetermined position before the target stop position,
From that point on, electrical braking is applied to the motor, such as by plucking, and the wheels are decelerated on each track. When the predetermined electrical braking is completed, the crane should have reached the target stop position, and finally the rotation of the running wheels is completely stopped by mechanical braking such as an electromagnetic brake. As a result, if the crane is meandering, the running wheels along the leading track will be braked at an early point, and the running wheels along the trailing track will start braking at a later point, allowing the lagging side to catch up to the leading side to some extent. become. Therefore, the attitude of the crane is significantly modified in the stopped state.

[Problem to be solved by the invention]

However, each of the decelerations and stops described above is performed by independent braking of both electric motors without any relation to the running wheels on the other track, so when an unpredictable load occurs transiently through the girder, the above-mentioned The disadvantage is that the control becomes unstable. Moreover, the crane is required to behave differently depending on the track, and there is the problem that unreasonable forces may be applied to the crane's mechanical system, including the support structure for the running wheels.

In addition, a position detector is required for each trajectory, and a speed control device that performs arithmetic processing based on the position detector is also essential for each electric motor, resulting in a considerable cost increase. Furthermore, with the position detector, the crane may not be able to be stopped at the desired stop position due to detection errors in the resolver itself or slips in the touch rollers that are in contact with the track.

The present invention has been made to solve the above-mentioned problems, and its purpose is to stop the crane within the target stopping position range and to correct the stopping posture of the crane without applying excessive force to the crane. To provide a crane travel positioning method which can be realized using a simple and inexpensive control device.

[Means to solve the problem]

In the present invention, the running wheels that move along two separate tracks are driven by electric motors provided independently for each track, and a position detector is attached to the crane to detect the position of the crane on one track. Applicable to a crane whose speed is controlled so that the traveling speed when reaching the tip of the target stop range becomes a predetermined decelerated speed value based on the crane's current position detected by the crane. .

The characteristics of the first invention are mainly shown in FIG. A dog detector 17 provided on the first side of the crane 2 indicates that the dog 15 on the first side track 6A is
Accordingly, the dog 16 on the second side track 6B where the position detector 9 is not provided is detected earlier than the dog detector 18 provided on the second side on the crane 2. Then, the running wheels 7 on the first side track 6A are caused to coast from a predetermined speed value, and at the same time, the running wheels 8 on the second side track 6B are maintained at a predetermined speed value and run at a constant speed.
When the stop command dog 16 on the track 6B running at a constant speed is detected by the dog detector 18 provided on the second side, the drive of the electric motor 11 running at a constant speed is released and , both running wheels 7 and 8 are simultaneously stopped by mechanical braking such as electromagnetic brakes 19 and 20.

In the second invention, with reference to FIG. 5, the second side track 6B where the position detector 9 is not provided
The dog 16 is detected by the position detector 9 by the dog detector 18 provided on the second side on the crane 2.
If the dog 15 on the first side track 6A is detected before it is detected by the dog detector 17 installed on the first side on the crane 2, then The speed control on the track 6B is maintained to further decelerate the running wheels 8, and at the same time, the electric motor 10 is reduced on the first track 6A.
The drive of the wheel 7 is released and the running wheels 7 are allowed to coast from the speed at that time. And that coasting trajectory 6A
When the stop command dog 15 is detected by the dog detector 17 provided on the first side, both running wheels 7 and 8 are simultaneously stopped by mechanical braking such as electromagnetic brakes 19 and 20. It is.

In the third invention, with reference to FIG. 17, the dog 16 on the second side track 6B where the position detector 9 is not provided is detected by the dog detector 18 provided on the second side on the crane 2. When detected, the running wheels 7 on the first side track 6A are decelerated by mechanical braking such as the electromagnetic brake 19, and at the same time, the running wheels 8 on the second side track 6B are maintained at a predetermined speed value. and drive at a constant speed.
When the stop command dog 16 on the track 6B running at a constant speed is detected by the dog detector 18 provided on the second side, the drive of the electric motor 11 running at a constant speed is released, The running wheel 8 is also brought to a stop by decelerating it by mechanical braking such as the electromagnetic brake 20.

In the fourth invention, with reference to FIG. 7, the second side track 6B is provided with no position detector 9.
The dog 16 is detected by the position detector 9 by the dog detector 18 provided on the second side on the crane 2.
If the dog 15 on the first side track 6A is detected before it is detected by the dog detector 17 installed on the first side on the crane 2, then The drive of the electric motor 11 on the track 6B is released and the running wheels 8 are decelerated by mechanical braking such as the electromagnetic brake 20, and at the same time, the speed control on the first side track 6A is maintained to keep the running wheels 7 at a predetermined level. Decelerate to the speed value. When the stop command dog 15 on the decelerating track 6A is detected by the dog detector 17 provided on the first side, the running wheel 7 is also moved to the electromagnetic brake 1.
It is to stop the vehicle by decelerating it by mechanical braking such as 9.

〔Example〕

The method of the present invention will be explained in detail below using a crane to which it is applied.

Figure 1 is an overall view of a coil yard 1 and an overhead crane 2 moving above it. During this time, the coils are stored on a large number of coil skids 3 arranged in an orderly manner.

The overhead crane 2 transports the coil as needed, and the girder 2 that runs vertically above the skid 3
A and a club 2b running horizontally above the club 2b, and the club is equipped with a coil tong 5 which holds a coil 4 so as to be movable up and down.

In order to allow such a crane 2 to move vertically, two separated tracks 6A and 6B are laid on the upper side wall of the coil yard 1. Running wheels 7 and 8 that move along these tracks are provided independently for each track and are driven by an electric motor (not shown).

As shown in FIG. 2, a position detector 9 such as a synchro resolver is provided on the crane 2 corresponding to one of the tracks, for example 6A, for detecting the longitudinal position of the crane. This is a well-known device consisting of a touch roller that rolls in contact with the track 6A, a resolver that detects its rotation speed, etc., and constantly detects the position of one side of the girder via the track 6A. . In addition, if errors due to slips in the rotation of the rollers cannot be avoided, the detected values can be made even more accurate by making it possible to correct fixed points using phototubes every 10 m along the trajectory. It can be done.

In response to the current position signal of the crane 2 detected by the position detector 9, the electric motors on both of the above-mentioned tracks set the traveling speed when reaching the tip of the target stop range to a reduced predetermined speed value. For example, braking is applied using predetermined electrical speed control such as plucking until the speed reaches 5% of the normal running speed.

What percentage of the crane's normal running speed V is set as the predetermined speed value in braking by this speed control varies depending on the inertia of the crane and the coil and the magnitude of the frictional force between the track and the running wheels. However, a value that allows the crane to fall within a predetermined target stop position range is determined in advance and selected as 0.05V mentioned above.

Note that the crane is separately instructed as to which of the many coil skids 3 to stop at, so it is calculated from the crane's current position detected by the position detector 9, and the crane moves from the target stop position. When the vehicle reaches a predetermined position, the motor is controlled to decelerate using a route curve.

In that case, the distance between the current position detected by the position detector 9 and its target stop position is sequentially detected, and the speed to be taken at that time is calculated.
The above speed control is continued for that distance until the stop target position.

Next, the configuration of the device for realizing the present invention is as follows.
This will be explained with reference to FIG. 3, although it partially overlaps with the above description.

The crane 2 includes a position detector 9 that detects the crane position on the track 6A side, and receives the detection signal to calculate the rotational speed of the electric motors 10 and 11.
A speed control unit 14 that commands a controlled speed while monitoring the speed from the generators 12 and 13 that detects the current rotational speed of the electric motor, and each track 6A,
Dog detectors 17 and 18, such as phototubes, are installed in parallel to the stop command dogs 15 and 16 as shown in FIG. Electromagnetic brakes 19 and 20 are installed to stop the motor.

Note that since the present invention relates to stop control of the crane 2 in the longitudinal direction, descriptions regarding the structure and function of the club 2b that moves laterally, and the stop control thereof will be omitted.

According to such a device, as follows,
While correcting the meandering posture of crane 2,
The crane 2 can be stopped within the range where the stop command dogs 15 and 16 are located, which is the target stop position.

In the following explanation, in any case, based on the position detected by the position detector 9, the electric motor is 10,1
1, the vehicle is in a running state in which braking is applied by electrical speed control in response to a command from the speed control unit 14.

First, at the [] target stop position, each trajectory 6A,
Of the stop command dogs 15 and 16 provided for each 6B, the dog 15 on the first side track 6A where the position detector 9 is provided is the dog 15 on the second side track 6B where the position detector 9 is not provided. The case where the phototube 17 detects the signal before the dog 16 is detected will be described.

In this case, as shown in FIG. 4, the speed of the running wheels 7 on the first side track 6A is controlled to a predetermined speed value of 0.05V by the above-mentioned speed control using electrical braking.
It's getting old. Therefore, the running wheel 7 is caused to coast from a speed of 0.05V, and the running speed is slightly reduced.

On the other hand, since the running wheels 8 on the second side track 6B are delayed, the phototube 18 is still in the stop command dog 1.
6 is not detected. However, the speed of the running wheels 8 is kept at a predetermined speed value of 0.05V by the speed control described above.

Therefore, at the same time as the above-mentioned coasting starts, the speed of the running wheels 8 on the second side track 6B is set to a predetermined speed value.
Maintain the voltage at 0.05V and start constant speed driving. In other words, since the running wheels 8 run at a faster speed than the running wheels 7 from that point on, the track 6B side of the crane 2 approaches the track 6A side, and the crane that was in state M changes to a position similar to state N. Fixed.

Next, when the stop command dog 16 on the track 6B running at a constant speed is detected by the phototube 18, the drive of the electric motor 11 that is running at a constant speed is released, and at the same time, both running wheels 7 and 8 are stopped. At the same time, it is mechanically braked by electromagnetic brakes 19 and 20,
The running wheels stop together.

At that time, since the speed of the running wheels 7 was low, the distance required for stopping the vehicle was also shorter than that for the running wheels 8. Therefore, the posture is further corrected as in state P. In addition, there are cranes 2 above and below in Figure 4.
The speed at that time is shown corresponding to the position on each orbit, making it easier to understand.

In this way, even if the crane 2 is in a meandering state during normal travel, its posture is corrected when it stops, so that the coil tongs 5 can clamp the coil and the coil can be placed on the coil skid 3 smoothly. It will be done.

Next, [] the stop command dog 16 on the second side track 6B where the position detector 9 is not provided,
First side track 6A where position detector 9 is provided
The case where the phototube 18 detects the signal before the dog 15 will be described.

In this case, as shown in FIG. 5, since the running wheel 7 on the track 6A has not reached the stop command dog 15, its speed has not been reduced to the predetermined speed value of 0.05V. Therefore, the speed of the running wheels 8 on the track 6B is also higher than 0.05V, e.g.
It is 0.10V. Therefore, the electrical braking of the motor on the second track 6B is maintained to further decelerate the running wheels 8 to a predetermined speed value of 0.05V.

On the other hand, since the running wheels 7 on the first side track 6A are delayed, the phototube 17 is still at the stop command dog 1.
5 is not detected. Therefore, the speed of the running wheels 7 is kept at 0.10V by the above-mentioned control. Therefore, at the same time as the stop command dog 16 is detected, the driving of the electric motor is canceled on the first side track 6A, and the running wheel 7 is caused to coast from the current speed of 0.10V. That is, since the running wheel 7 travels at a faster speed than the running wheel 8 from that point on, the crane 2
The side of the track 6A approaches the side of the track 6B, and the crane, which was in state Q, is slightly corrected to a posture similar to state R.

Next, when the stop command dog 15 on the coasting track 6A is detected by the phototube 17,
The drive of the electric motor 11 that maintains electric braking and makes the running wheels 8 decelerate is released, and at the same time, both running wheels 7 and 8 simultaneously apply the electromagnetic brakes 19 and 20.
mechanically braked. At this time, since the speed of the running wheels 8 is low, the distance required for stopping is also shorter than that for the running wheels 7. Therefore, the posture is further corrected as in state S.

By the way, by adopting the combination of the above-mentioned items [ ] and [ ], it is possible to create one system in which the predetermined control can be achieved regardless of which side of the crane is leading.

Next, [] the stop command dog 15 on the first side track 6A where the position detector 9 is provided is transferred to the second side track 6B where the position sensor 9 is not provided.
A case will be described in which the detection occurs earlier than the dog 16 in .

This is the same situation as in item [ ].
In FIG. 6, the running wheel 7 on the first side track 6A has reached a predetermined speed value of 0.05V, and at the same time as the above-mentioned dog 15 is detected, the electromagnetic brake 1
9 is mechanically braked. At that time, the running wheels 8 on the second side track 6B also have a predetermined speed value of 0.05V.
is reached, but maintain that speed and drive at a constant speed.

Thereafter, when the stop command dog 16 on the track 6B running at a constant speed is detected, the drive of the electric motor 11 that is running at a constant speed is released, and the running wheels 8
is mechanically braked. As a result, the attitude of the crane is corrected, and its stop position falls within the range of the stop target position where the stop command dog is installed.

Finally, [] the stop command dog 16 on the second side track 6B where the position detector 9 is not provided.
, is detected before the dog 15 on the first side track 6A where the position detector 9 is provided will be described.

This is the same situation as in item [ ].
In FIG. 7, although the running wheel 8 on the second side track 6B has not reached the predetermined speed value of 0.05V, the drive of the electric motor 11 is released and the running wheel 8 is mechanically braked. At the same time, the electrical braking of the electric motor 10 on the first side track 6A is maintained, and the running wheels 7 are decelerated to a predetermined speed value of 0.05V. after that,
When the stop command dog 15 on the decelerating track 6A is detected, the running wheels are mechanically braked.

By the way, by adopting the combination of the above-mentioned items [ ] and [ ], it is possible to create one system in which the predetermined control can be achieved regardless of which side of the crane is leading. Although this example uses a crane that uses electric braking to control the speed until it reaches the tip of the target stop range, it uses a well-known electro-hydraulic braking device called a thruster. The present invention can also be applied to such cases.

〔Effect of the invention〕

As described in detail above, the present invention provides for the detection of a dog on a first side track where a position detector is provided and a dog on a second side track where a position sensor is not provided before and after detection. Since the mode of deceleration of the running wheels on each track is different, and both running wheels are mechanically braked upon detection of a stop command dog, the crane can be stopped within the range of a predetermined target stop position.

Furthermore, even if the crane is meandering during normal travel, it can be corrected without applying excessive force to the crane when it stops, and the coil tongs can be used to clamp the coil and the coil can be mounted on the coil skid. done smoothly. Furthermore, it can be realized with a simple and inexpensive device that is controlled by receiving a signal from a single position detector.

[Brief explanation of drawings]

Figure 1 is an overall diagram of the arrangement of overhead cranes in the coil yard, Figure 2 is a schematic diagram of the configuration of the crane that moves above the coil skid, Figure 3 is a schematic system diagram of each component used to control the crane, and Figure 4 7 to 7 are explanatory diagrams of the stopping operation of the crane according to the present invention. 2... Crane, 6A, 6B... Orbit, 7, 8
...Running wheel, 9...Position detector (synchronized resolver), 10,11...Electric motor, 15,16...
Stop command dog, 17, 18... dog detector (phototube), 19, 20... electromagnetic brake.

Claims (1)

[Claims] 1. A position detector that detects the position of a crane on one of the tracks, in which running wheels that move along two separate tracks are driven by electric motors provided independently for each track. is provided in the crane, and the speed is controlled based on the current position of the crane detected by the crane so that the traveling speed when reaching the tip of the target stop range becomes a predetermined speed value that is decelerated. , Among the stop command dogs provided for each trajectory in the stop target range, the dog on the first side trajectory where the position detector is provided is detected by the dog provided on the first side on the crane. If the dog on the track on the second side, which is not equipped with a position detector, is detected by the device earlier than the dog on the second side of the track on the crane is detected. , the running wheels on the first side track are allowed to coast from the predetermined speed value, and at the same time, the running wheels on the second side track are maintained at the predetermined speed value and run at a constant speed; When a stop command dog on the track is detected by the dog detector installed on the second side, the drive of the electric motor that is running at a constant speed is released, and both running wheels are simultaneously activated by an electromagnetic brake, etc. A crane traveling positioning method characterized by stopping the crane by mechanical braking. 2. The running wheels that move along two separate tracks are driven by electric motors provided independently for each track, and the crane is provided with a position detector that detects the position of the crane on one track, In a crane whose speed is controlled so that the traveling speed upon reaching the tip of the target stop range becomes a decelerated predetermined speed value based on the current position of the crane detected thereby, in the target stop range. Among the stop command dogs provided for each track, the position of the dog on the second track where the position detector is not provided is determined by the dog detector provided on the second side on the crane. If a dog in the track on the first side on which the detector is installed is detected before it is detected by the dog detector on the first side on the crane, then the dog on the second side The speed control on the track is maintained to further decelerate the running wheels, and at the same time, on the first track, the drive of the electric motor is released and the running wheels coast from the current speed. When a stop command dog on a track is detected by the dog detector provided on the first side, both running wheels are simultaneously stopped by mechanical braking such as an electromagnetic brake. travel positioning method. 3. Running wheels that move along two separated tracks are driven by electric motors provided independently for each track, and the crane is provided with a position detector that detects the position of the crane on one of the tracks, In a crane whose speed is controlled so that the traveling speed upon reaching the tip of the target stop range becomes a decelerated predetermined speed value based on the current position of the crane detected thereby, in the target stop range. Of the stop command dogs provided for each track, the position of the dog on the first track where the position detector is provided is determined by the dog detector provided on the first side on the crane. If a dog on the track on the second side where no detector is installed is detected before it is detected by the dog detector on the second side on the crane, the dog on the first side The running wheels on the track are decelerated by mechanical braking such as electromagnetic brakes,
At the same time, the running wheels on the second side track are maintained at the predetermined speed value and run at a constant speed, and the stop command dog on the track running at a constant speed is transmitted to the dog detector provided on the second side. When this is detected, the driving of the electric motor that is driving the crane at a constant speed is deactivated, and the running wheels of the crane are also decelerated by mechanical braking such as an electromagnetic brake, thereby stopping the crane. Positioning method. 4. Running wheels that move along two separate tracks are driven by electric motors provided independently for each track, and the crane is provided with a position detector that detects the position of the crane on one of the tracks, In a crane whose speed is controlled so that the traveling speed upon reaching the tip of the target stop range becomes a decelerated predetermined speed value based on the current position of the crane detected thereby, in the target stop range. Among the stop command dogs provided for each track, the position of the dog on the second track where the position detector is not provided is determined by the dog detector provided on the second side on the crane. If a dog in the track on the first side where the detector is installed is detected before it is detected by the dog detector on the first side on the crane, then the dog on the second side The drive of the electric motor on the track is released and the running wheels are decelerated by mechanical braking such as an electromagnetic brake, and at the same time, speed control on the first track is maintained and the running wheels are decelerated to the predetermined speed value. , When the stop command dog on the decelerating track is detected by the dog detector provided on the first side, the running wheel is also decelerated by mechanical braking such as an electromagnetic brake. A crane traveling positioning method characterized by stopping the crane.