JP2003012274A - Method of controlling crane for carrying suspended cargo - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of controlling a crane with a secondary resistance controlling drive device for carrying a suspended cargo capable of preventing the swing of the suspended cargo and positioning the crane precisely and securely. SOLUTION: The method of controlling the crane for carrying a suspended cargo is to control the speed by controlling the secondary resistance. The method comprises a running step of running the crane together with the suspended cargo to a position just before a target position, and a positioning step of performing at least one swing preventive inching 10 of the cargo along the running direction of the crane and at least one positioning inching 14 of the crane if necessary.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a crane for transporting various loads while suspending them in a factory or the like. The crane controls speed by secondary resistance control, and steadys the suspended load and controls the positioning of the crane. The present invention relates to a method for controlling a crane for carrying suspended goods.

[0002]

2. Description of the Related Art Recently, it has been required to reduce the labor required for overhead cranes and yard cranes. However, in order to accurately convey the load to the target point, it is necessary to hang it with a wire or rope. It is necessary to accurately perform steadying of the suspended load and positioning control of the crane. Normally, when steady rest control or positioning control is performed, the crane itself has inverter control or 1
This is often done by mounting a drive device for controlling the secondary voltage.
The steady rest and positioning control software are commercially available for use in cranes equipped with either of the above two types of control drive devices. In addition, the relatively small crane can be easily modified by mounting the control drive device, which is inexpensive, and installing the control software.

[0003]

However, in the case of a relatively large-sized crane used in a steelmaking plant or the like, since it is operated by secondary resistance control which is a conventional drive device, the control performance is poor and automatic control is not possible. Not suitable. Moreover, in order to realize automatic control, it was still costly to mount a drive device for inverter control or primary voltage control and install the control software.

Further, the inverter control performs speed control by controlling the rotational speed of the drive motor, and the primary voltage control performs speed control by controlling the primary voltage of the drive motor. However, in the case of secondary resistance control of a large crane, It accelerates by changing the resistance of the drive motor, and decelerates by braking the motor. For this reason, there is a problem that automatic control is difficult because the acceleration characteristics and the deceleration characteristics change depending on the suspended load and the transportation condition at each occasion. The present invention solves the problems in the conventional techniques described above, and provides a crane control method that can accurately and reliably perform steadying and positioning of a suspended load in a crane equipped with a drive device for secondary resistance control. , Is the task.

[0005]

SUMMARY OF THE INVENTION In order to solve the above problems, the present invention performs speed control by secondary resistance control and performs standardized steady rest inching just before a transfer target point for a suspended load. Is based on the idea that positioning inching is also performed. That is, the crane control method (Claim 1) of the present invention is a method for controlling a crane for carrying a suspended load that performs speed control by secondary resistance control. And a positioning process of performing at least one steady rest inching of the suspended load along the traveling direction of the crane at a position immediately before the conveyance target point. .

According to this, when the position immediately before the transfer target point is reached while the speed is controlled by the secondary resistance control, the load hung by a wire or the like swings along the traveling direction of the crane. Stop inching is applied. As a result, the moment of inertia of the suspended load itself can be suppressed or reduced, and the motion of suppressing the shake can be accurately performed. Therefore, the suspended load can be accurately conveyed to the target point or its vicinity by a simple operation. The secondary resistance control refers to a control method in which the resistance or reactance of the motor is changed during acceleration and the brake of the motor is applied during deceleration.
Further, the steady rest inching refers to a continuous driving action in which a manual on / off operation is performed in about 1 second each to stop the swing of a suspended load,
One-time inching means that the on / off operation is performed once.

According to the present invention, the positioning process is
A crane control method (claim 2) is also included, which is performed together with at least one steady rest inching of the suspended load along a direction orthogonal to the traveling direction of the crane. According to this, when the position immediately before the transport target point is reached, with respect to the suspended load suspended by the wire or the like, along both the traveling direction of the crane and the direction orthogonal thereto,
Steady inching is added. As a result, the moment of inertia of the suspended load itself can be suppressed and reduced, and the motion of suppressing the shake can be performed more accurately, so that the suspended load can be accurately and reliably transported to or near the target point by a simple operation.

Further, according to the present invention, the positioning process includes:
A crane control method, further comprising at least one positioning inching of the crane after the steady rest inching of the suspended load along at least one of the traveling direction of the crane and the direction orthogonal thereto. 3) is also included. According to this, when the position immediately before the transport target point is reached while the speed is controlled by the secondary resistance control, the traveling direction of the crane and the direction orthogonal to the traveling direction of the crane are suspended with respect to the suspended load suspended by the wire or the like. After performing steady rest inching of the suspended load along one or both sides,
In addition, positioning inching of the crane is performed when necessary for stopping accuracy. As a result, the moment of inertia of the suspended load itself can be suppressed and further reduced, so that the steady rest control of the suspended load and the positioning control of the crane can be performed more accurately. Therefore, the suspended load can be more accurately and surely transported to the target point and its vicinity by a relatively simple operation.

The above-mentioned positioning inching is an operating action in which a motor for operating the crane is turned on and off once each for about 1 second in order to position the crane. It refers to the operation that is continuously performed until it enters the allowable range of the set stop position. If the vehicle moves too far in the traveling direction, the positioning inching is performed along the direction opposite to the traveling (traveling) direction until the stop position falls within the allowable range. In addition, in the present invention, in the traveling process, the crane (and its motor) is temporarily stopped after traveling the crane together with a suspended load to a position immediately before the transportation target point, or the crane. A method of controlling a crane (claim 4), in which the vehicle is decelerated and then stopped (the motor thereof) is temporarily stopped, is also included. According to this, since the steady rest inching of the suspended load and the positioning inching of the crane can be performed immediately after the crane is significantly decelerated or stopped, it is easy to accurately perform each of the above inching operations. .

In the traveling process, the traveling speed of the crane is alternated between acceleration and deceleration alternately after the traveling speed of the crane is alternately accelerated or decelerated according to the distance for conveying the suspended load or the transportation route of the suspended load, or the crane is initially accelerated. Various driving patterns are selected, such as a constant speed on the way and a temporary stop while decelerating by several steps. In addition, the operator operates in an operation room attached to the crane itself, or operates an operation panel suspended from the crane on the ground. Alternatively, the crane can be operated wirelessly, and an operation command is given and operated from the ground by a wireless operation controller (transmitter) having an operation lever or an operation button. Thereby, one of the control methods described above is executed for the crane. At this time, the operator can perform each of the inchings by performing a quick operation on the lever or continuously pressing the button for a short time.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, preferred embodiments for carrying out the present invention will be described with reference to the drawings. FIG. 1A shows an overhead crane 1 for carrying a suspended load to which the control method of the present invention is applied. This overhead crane 1 is, as shown in FIG.
A deck-shaped and rectangular main body 2 movably supported by a pair of parallel rails R, R laid near the ceiling of a building such as a factory via wheels 4 and 4, and a longitudinal direction of the main body 2. And a suspending portion 5 that can be horizontally moved by a motor (not shown) along. On the hanging part 5 concerned,
Drums 6 and 7 rotated by a dedicated winding motor (not shown) are positioned, and a load 9 is hung from and supported by wires 8 and 8 hung from the drums 6 and 7 so that the load 9 can be moved up and down. That is, the suspension part 5 is capable of moving in the horizontal direction between the rails R and R while supporting the suspended load 9 so as to be able to move up and down.

Incidentally, the operator is in an operation room (not shown) attached to a position on the bottom surface of the main body 2 near any of the rails R, and turns on / off the lever or button of the operation panel. Alternatively, if the crane 1 can be wirelessly operated, the crane 1 and the suspension unit 5 can be operated by giving an operation command from the ground by a wireless operation control (transmitter) having an operation lever or an operation button (not shown). And control. Further, the suspended load 9 in FIG. 1A is, for example, a relatively large ladle into which molten steel is poured.

As shown in FIG. 1 (A), for example, in an overhead crane 1 in which a suspended load 9 is suspended and supported at a position indicated by a broken line on the left side, a suspended portion 5 together with a suspended load 9 under a main body 2 thereof is A driving motor (not shown) of the suspension unit 5 horizontally moves T1 toward the front rail R in FIG. 1A (direction orthogonal to the traveling direction of the crane).
Next, the drive motor (not shown) of the main body 2 travels the main body 2 along the longitudinal direction of the rails R, R (the traveling direction of the crane) for a predetermined distance F. Further, as indicated by the solid line in FIG. 1 (A), the overhead crane 1 traveling to the right F has the hanging portion 5 together with the suspended load 9 under the main body 2 thereof, and its driving motor in FIG. 1 (A). By horizontally moving T2 toward the rail R on the far side (direction orthogonal to the traveling direction of the crane), the suspended load 9 is transported to a target point and lowered to land. The traveling F and the horizontal movements T1 and T
The speed control in 2 is performed by the secondary resistance control.

The traveling F in the traveling direction of the crane 1 and the horizontal movement T1, T in the direction orthogonal to the traveling direction of the crane.
2 is performed simultaneously, as shown in FIG. That is,
The suspended load 9 and the suspended portion 5 are horizontally moved T1 and run F.
By using together with, the vehicle moves along the locus f1 shown by the one-dot chain line in FIG. 1 (B), and by using the traveling F and the horizontal movement T2 in combination, the two-dot chain line in FIG. Locus f
Move along 2.

By the way, the traveling F of the main body 2 of the overhead crane 1, and the hanging portion 5 and the suspended load 9 in the main body 2 are related.
The horizontal movements T1 and T2 are performed by the drive motor on the main body 2 and the drive motor of the suspension unit 5, and speed control of these is performed by secondary resistance control. That is, in the traveling F and the horizontal movements T1 and T2, the speed is adjusted by changing the resistance or reactance of each drive motor during acceleration and controlling the brake of each drive motor during deceleration. In other words, the speed control during the traveling F and the horizontal movements T1 and T2 is performed by open control. Then, at each end point of the traveling F, the horizontal movement T2, and the locus f2, the swing of the suspended load 9 is eliminated or reduced, or at least the horizontal movement T2 or the locus f is generated.
By eliminating or reducing the swing of the suspended load 9 at the end point of 2, the suspended load 9 can be accurately transported to the transport target point.

The control method of the overhead crane 1 whose speed is controlled by the secondary resistance control will be described below. FIG. 2A shows a traveling pattern of the crane 1, that is, a control pattern of the traveling F when the suspended load 9 is conveyed over a short distance. 2D shows a control pattern of the horizontal movement T in a direction orthogonal to the traveling direction of the crane 1 in the same case. In the following, in the traveling direction of the crane 1 and the direction orthogonal thereto, the main body 2
The control operation for each drive motor of the suspension unit 5 will be described, but these will be described as motors in respective directions.

As shown in FIG. 2A, in order to convey the suspended load 9 in a short distance along the traveling direction, first, the crane 1 is moved along the traveling direction at a relatively low speed level. The vehicle accelerates to an upper limit speed v1 in a speed range between a certain upper limit speed v1 and a lower limit speed v2. For this reason, the first speed (notch) of the notch circuit (not shown) is applied at the time of starting to accelerate (start on), but when the upper limit speed v1 is reached, the notch circuit is turned off (d1). At this time, the brake of the motor is not applied, and the crane 1 is allowed to travel freely only by the inertial force until the lower limit speed v2 is reached. The notch circuit is a circuit for gradually reducing the resistance of the motor.

Next, in order to drive the crane 1 in a short distance F, when the vehicle is decelerated to the lower limit speed v2, the first speed of the notch circuit is input again to accelerate (u1), and when the upper limit speed v1 is reached. The notch circuit is turned off (d2) for free running, and the notch circuit is turned on (u2) when the lower limit speed v2 is reached. The on / off operation is repeatedly performed until the remaining distance to the transport target point reaches the brake start distance, and the crane 1 travels F to a position immediately before the transport target point. Next, when the brake start distance is reached, the motor is temporarily stopped (stopped), so the brake (Br)
The traveling speed V is reduced by multiplying by. With the above, the traveling process F of the crane 1 is completed. The above-mentioned braking start distance is conceptually shown in FIG.

Further, as shown in FIG. 2 (A), the crane 1
The steady rest inching (intermittent operation) 10 of the suspended load 9 is performed by turning on 11 and turning off 12 for the motor. When the traveling speed V is, for example, 50 mm / sec or less, the on 11 performs the off 12 in which the first speed of the notch circuit is applied to drive the motor for about 1 second, and then the motor is braked for about 1 second. This eliminates or reduces the shake of the suspended load 9 along the traveling direction. Immediately after the steady rest inching 10, the positioning inching 14 of the crane 1 is subsequently performed if necessary. Also, as shown in FIG. 2 (A), with respect to the motor of the crane 1, the first speed of the notch circuit is turned on to drive the motor for about 1 second and the ON 15 is set to about 1 for the motor.
The off 16 for applying the brake for a second is repeated until the stop position is within the allowable range.

If the crane 1 goes too far, it will travel.
The positioning inching 14 is performed along the direction opposite to the (advancing) direction. A flow chart of the operation of the inching 14 is shown in FIG. 2C, and the subsequent inching operations are also performed by the same flow. As a result, the positioning process is performed, and the suspended load 9 can be accurately transported to the transport target point without any shake. In addition, when the steady rest inching 10 is performed in the positioning process, the suspended load 9 stops at the stop position.
When it is located within the allowable range of (transportation target point), the positioning inching 14 is omitted.

As shown in FIG. 2 (D), the horizontal movement T for conveying the suspended load 9 for a short distance in the direction orthogonal to the traveling direction of the crane 1 is controlled by turning on the first speed of the notch circuit at the time of starting. Then, the notch is not switched until the maximum speed set by the horizontal movement T is reached. Next, as shown in FIG. 2D, after the horizontal movement T is performed until the distance to the transport target point reaches the brake start distance that is a predetermined distance, the motor Br is temporarily stopped (stopped). The traveling speed V is reduced by multiplying by. And FIG.
As shown in (D), steady rest inching 20 and positioning inching 24 are performed on the motor of the suspended load 9 (suspended portion 5). On 21 of steady rest inching 20
Is for turning on the first speed of the notch circuit to drive the motor for about 1 second when the moving speed V is less than or equal to a predetermined value, and subsequently, the brake 22 is applied to the motor for about 1 second to turn off 22. . As a result, the shake along the direction (horizontal movement direction) orthogonal to the traveling direction of the suspended load 9 is eliminated or reduced.

Subsequently, as shown in FIG. 2 (D), the first speed of the notch circuit is applied to the motor of the suspending unit 5 to turn on the motor for about 1 second, and to turn on the motor for about 1 second. The positioning inching 24 for performing the off 26 for applying the brake for 1 second is repeated as in the flow chart of FIG. 2C until the stop position is within the allowable range. As a result, the suspended load 9 can be accurately transported to the transportation target point without any shake. In addition, when it goes too far, the positioning inching 24 is performed along the direction opposite to the moving direction. If the suspended load 9 is located within the permissible range of the conveyance target point when the steady rest inching 20 is performed, the positioning inching 24 is not performed.

FIG. 3A shows a control pattern of the traveling direction of the crane 1, that is, the traveling F when the suspended load 9 is conveyed at a relatively medium distance. Further, FIG. 3C shows a control pattern of the horizontal movement T in a direction orthogonal to the traveling direction of the crane 1 in the case where the crane 1 is also conveyed at an intermediate distance. As shown in FIG. 3 (A), since the suspended load 9 is conveyed at an intermediate distance, the crane 1 is first accelerated along the traveling direction of the crane 1, but the load run-out that occurs at the start is suppressed. Accelerate to level. For this reason, the first speed of the notch circuit is also turned on (start on) to perform the operation of suppressing the shake of the load at the time of start, and after starting the engine, the notch circuit is turned off (start off) and the crane 1 is freed. Let it run.

Next, while suppressing the swing of the suspended load 9 at the time of starting, the load 9 is accelerated to a speed range between the upper limit speed v1 and the lower limit speed v2 at a relatively intermediate speed level. For this reason, the notch circuit is turned on (Non) again at a timing empirically required that is suitable for suppressing the load shake at the start,
For example, the notch is switched from the first speed to the fourth speed at a preset timing. Next, when the upper limit speed v1 is reached, the crane 1 is run until the distance to the target point becomes the deceleration preparation distance. Therefore, the motor d
1, on-u1, off-d2, on-u2 are repeated during the traveling F1. After that, when the distance to the target point reaches the deceleration preparation distance K, the notch circuit is turned off and the crane 1
Free running (vc). Then, when the distance to the target point reaches the first brake start distance, the brake B
Multiply r1. Further, as shown in FIG. 3 (A), in order to prepare for deceleration, deceleration is performed up to the upper limit speed v3 in the speed range between the upper limit speed v3 and the lower limit speed v4, which are relatively low speed levels.
When (d3) is reached, the brake is released, and free running (d4) is again performed only by the inertial force.

After that, at the speeds v3 to v4, the motor of the crane 1 is turned on u3, turned off d5, and turned on u4 in order to drive the crane 1 for a predetermined distance F2. Then, when the distance to the transportation target point (transportation point) of the crane 1 reaches the second brake start distance, the motor Br is temporarily stopped (stopped), and therefore the brake Br2 is applied to reduce the traveling speed V. The traveling processes F1 and F2 are completed. Note that FIG. 3B conceptually shows the deceleration preparation distance and the first and second brake start distances described above. Finally,
As shown in FIG. 3 (A), with respect to the motor of the crane 1,
The steadying inching 10 similar to the above is performed according to the flow chart of FIG. 2 (C), and the positioning inching 14 is performed as necessary to form a positioning process.

The control of the horizontal movement T of the hanging load 9 in the direction orthogonal to the traveling direction of the crane 1 is shown in FIG. 3 (C). When the suspended load 9 is conveyed at an intermediate distance, the load 9 is accelerated to a certain speed level in order to suppress the vibration of the load generated at the time of starting. For this reason, the first speed of the notch circuit is also turned on (start on) to perform the operation of suppressing the shake of the load at the time of start, and after starting the engine, the notch circuit is turned off (start off) and the crane 1 is freed. Let it run. Next, in order to accelerate again so that the moving speed V reaches the speed level between the upper and lower speed limits v1 and v2, the notch circuit is turned on again (Non), and when the upper speed limit v1 is reached, the crane 1 is moved to the target point. The horizontal movement T is performed until the distance to becomes the deceleration preparation distance. Therefore, the motor of the suspension unit 5 is repeatedly turned off d1, on u1, off d2, and on u2 during the movement T. Further, when the crane 1 reaches the position of the brake start distance, the motor Br is temporarily stopped (stopped), so the brake Br is applied to reduce the traveling speed V. Then, as shown in FIG. 3C, the steady rest inching 20 similar to the above is performed on the motor, and the positioning inching 24 is performed as necessary.

FIG. 4A shows a control pattern of the traveling direction of the crane 1, that is, the traveling F when the suspended load 9 is conveyed over a long distance. Further, FIG. 4C shows a control pattern of the horizontal movement T, which is a direction orthogonal to the traveling direction of the crane 1 in the case of similarly carrying a long distance. As shown in FIG. 4 (A), since the crane 1 travels a long distance F, the crane 1 is first accelerated along the traveling direction of the crane 1, but in order to suppress the shake of the load that occurs at the start. Accelerate to speed level. For this reason, the first speed of the notch circuit is also turned on (start on) to perform the operation of suppressing the shake of the load at the time of start, and after starting the engine, the notch circuit is turned off (start off) and the crane 1 is freed. Let it run.

Next, as shown in FIG. 4A, the crane 1 is accelerated until the maximum traveling speed Vmax (about 1167 mm / sec) is reached while suppressing the swinging of the suspended load 9 at the time of starting.
For this reason, the notch circuit is turned on again at the empirically required timing suitable for suppressing the load shake at the start.
Then, the notch is switched from the first speed to the fourth speed at a preset timing. Next, when the maximum traveling speed Vmax is reached, the crane 1 is caused to travel at a constant speed Vc while maintaining the fourth speed notch.

Further, at the time K when the residual distance of the crane 1 reaches the deceleration preparation distance, the notch circuit is turned off to allow free travel Lc, and then the brake Br1 is applied to the motor at the time when the first brake start distance is reached. Then, the vehicle decelerates d1, and when the vehicle decelerates to a predetermined speed v1, the brake is released and the free running L1 is performed. Then, as shown in FIG.
At the time when the brake start distance is reached, the brake Br2 is applied to the motor again to decelerate d2, and when the speed is reduced to a predetermined speed v2, the brake is released and free running L2 is performed.
The deceleration preparation distance, the first and second brake start distances, and the third and fourth brake start distances described below are shown in FIG. 4 (B).
The concept is shown in.

Subsequently, when the third brake start distance is reached, the brake Br3 is applied to the motor to decelerate d3.
Then, when the vehicle decelerates to the predetermined speed v3, the brake is released and the free running L3 is performed. Further, when the crane 1 is decelerated to a predetermined speed v4, a relatively low speed level between the upper limit speed v3 and the lower limit speed v4 is reached until the remaining distance of the crane 1 to the conveyance target point becomes the fourth brake start distance. Run F in the speed range. Therefore, the motor is turned on u1, turned off d5, and turned on u2. And FIG.
As shown in (A), when the fourth brake start distance is reached, the motor is temporarily stopped (stopped).
By reducing the traveling speed V by
To finish. Finally, as shown in FIG. 4 (A), the crane 1
The same steady rest inching 10 for the motor of
After performing the above, a positioning process is performed in which the positioning inching 14 is performed if necessary.

The control of the horizontal movement T of the hanging load 9 in the direction orthogonal to the traveling direction of the crane 1 is shown in FIG. 4 (C).
When the suspended load 9 is conveyed over a long distance, the load is accelerated to a certain speed level in order to suppress the vibration of the load generated at the time of starting. For this reason, the first speed of the notch circuit is also turned on (start on) to perform the operation of suppressing the shake of the load at the time of start, and after starting the engine, the notch circuit is turned off (start off) and the crane 1 is freed. Let it run. Next, since the crane 1 accelerates until it reaches the maximum traveling speed Vmax while suppressing the swing of the suspended load 9 at the time of starting, the above-described timing is empirically required for suppressing the load swing at the time of starting. Turn on the notch circuit again
Then, the notch is switched from the first speed to the fourth speed at a preset timing. Next, at the time when the maximum traveling speed Vmax is reached, the constant speed traveling Vc is performed while maintaining the fourth speed notch.

Further, as shown in FIG. 4 (C), the crane 1
At the time point K when the residual distance reaches the deceleration preparation distance, the notch circuit is turned off and the free running Lc is performed, and then at the time point when the first brake start distance is reached, the brake Br1 is applied to decelerate d1 to a predetermined speed. When the vehicle decelerates to v1, the brake is released and free running L1 is performed. Then, when the second brake start distance is reached, the brake Br2 is applied again to decelerate d2, and when the vehicle decelerates to a predetermined speed v2, the brake is released and free running L2 is performed. After decelerating to the predetermined speed v3, as shown in FIG. 4C, in the speed range of low level speeds v2 to v3 until the remaining distance of the crane 1 reaches the third brake start distance, the suspended load 9 and the crane 1 are Is horizontally moved T by a predetermined distance, the motor of the suspension unit 5 is turned on u1, turned off d3, and turned on u2.

Then, when the third brake start distance is reached, the brake Br is stopped to temporarily stop (stop) the motor.
The traveling speed V is decelerated by taking 3. Finally, as shown in FIG. 4C, after the steady rest inching 20 similar to the above is performed on the motor of the suspension portion 5, the positioning inching 24 is further performed if necessary. In addition, in FIGS. 4A and 4C, when the hanging load 9 is located at the conveyance target point when the steady rest inching 10, 20 of the hanging load 9 is performed,
The positioning inchings 14 and 24 of the crane 1 may be omitted.

Further, the traveling of the crane 1 as described above (F)
FIG. 2A, FIG. 3A, and FIG. 4 showing direction control patterns.
2 (D), FIG. 3 (C), and FIG. 4 (C) showing control patterns of (A) and a movement (T) direction orthogonal to the traveling (F) direction,
Can also be performed in combination. As a result, the suspended load 9 can be efficiently transported to an arbitrary transport target point according to the transport distance. Further, the command of the brake Br in the deceleration process of each control pattern described above applies the brake Br according to the remaining distance to the transportation target point of the suspended load 9 or the crane 1 and decelerates the brake Br to the set speed. I am trying to open it. Therefore, there is also a feature that it is a safe control method for surely decelerating.

The present invention is not limited to each of the forms described above. For example, the crane that is the subject of the present invention includes a mode in which the load is transported only along the traveling direction of the crane, as long as the speed is controlled by the secondary resistance control. Further, for example, a gate-type self-propelled crane that runs on rails laid on the ground in a stockyard or the like is also included. In addition, in the steady rest inchings 10 and 20, one inching (on / off)
However, the inching may be performed twice or more. Further, for example, in FIGS. 4 (A) and 4 (C), the number of brakes applied to the motor (Br1 to Br4, Br1 to Br3) when decelerating to a relatively low speed range is increased or decreased according to the transport target distance. It is also possible to let. The traveling F of the crane 1 and the horizontal movement T of the suspended load 9 in the direction orthogonal to the traveling F may be performed together with the lifting or lowering operation of the suspended load 9 by the suspending unit 5.

[0036]

According to the crane control method (Claim 1) of the present invention described above, the speed of the crane is controlled by the secondary resistance control, and the crane is operated against the suspended load at the position immediately before the target point of conveyance. Since steady rest inching is performed along the traveling direction, the moment of inertia of the suspended load itself can be suppressed or reduced, and steady rest control can be performed accurately. Therefore, the suspended load can be accurately transported to the target point by a simple operation. Further, according to the crane control method of claim 2, at the position immediately before the target point of conveyance, steady rest inching is performed with respect to the suspended load along both the traveling direction of the crane and the direction orthogonal thereto. . For this reason, the moment of inertia of the suspended load itself can be suppressed and reduced, and steady rest control can be performed with higher accuracy, so that the suspended load can be accurately and reliably transported to the target point by a simple operation.

Further, according to the crane control method of the third aspect, one or both of the traveling direction of the crane and the direction orthogonal to the traveling direction of the crane are provided at the position immediately before the conveyance target point while the speed is controlled by the secondary resistance control. Along with, steady rest inching of the suspended load and positioning inching of the crane are performed. Therefore, the moment of inertia of the suspended load itself can be suppressed and reduced, and the steady rest control and the positioning control can be performed with higher accuracy, so that the suspended load can be more accurately and reliably conveyed to the target point by a relatively simple operation. In addition, according to the crane control method of claim 4, since the steadying inching of the suspended load and the positioning inching of the crane are performed immediately after the crane is significantly decelerated or stopped,
It becomes easy to perform each of the above-mentioned inching operations accurately.

[Brief description of drawings]

1A and 1B are schematic views showing an overhead crane to which the present invention is applied.

FIG. 2A is a schematic diagram showing a relationship between speed and time showing a traveling pattern including a control method of the present invention when a crane travels a short distance, and FIG. 2B is a conceptual diagram showing a brake start distance. , (C) is a flow chart showing the operation of steady rest inching, and (D) shows the relationship between speed and time, which shows the movement pattern when moving the load in the direction orthogonal to the traveling direction of the crane in (A). Pattern diagram.

FIG. 3A is a schematic diagram showing a relationship between speed and time showing a traveling pattern including a control method of the present invention when the crane travels a medium distance, and FIG. 3B is a conceptual diagram showing a deceleration preparation distance and the like. , (C) is a schematic diagram showing a relationship between speed and time showing a movement pattern when a suspended load is moved in a direction orthogonal to the traveling direction of the crane in (A).

4A is a schematic diagram showing a relationship between speed and time showing a traveling pattern including a control method of the present invention when the crane travels a long distance, and FIG. 4B is a conceptual diagram showing a deceleration preparation distance and the like. , (C) is a schematic diagram showing a relationship between speed and time showing a movement pattern when a suspended load is moved in a direction orthogonal to the traveling direction of the crane in (A).

[Explanation of symbols]

1 ……………… Overhead crane (crane) 9 …………… Suspended load 10, 20… steady rest inching 14, 24… Positioning inching F …………… Travel T …………… Horizontal movement (travel direction) Movement of suspended load along the direction orthogonal to the direction) Br ………… Brake (stop)

Claims (4)

[Claims] 1. A method for controlling a crane for carrying a suspended load, which performs speed control by secondary resistance control, comprising: a traveling process in which the crane travels in an arbitrary pattern along with a suspended load up to immediately before a target transport point; And a positioning step of performing at least one steady rest inching of the suspended load along the traveling direction of the crane at a position immediately before the point. 2. The positioning process is performed by using at least one steady rest inching of a suspended load along a direction orthogonal to a traveling direction of the crane. A method for controlling a crane for carrying a suspended load as described. 3. The positioning step further comprises at least one positioning inching of the crane after steadying inching of the suspended load along at least one of a traveling direction of the crane and a direction orthogonal to the traveling direction. The method for controlling a crane for carrying a suspended load according to claim 1 or 2, wherein: 4. In the traveling process, after traveling the crane together with a suspended load to a position immediately in front of a transportation target point in an arbitrary pattern, the crane is temporarily stopped, or the crane is decelerated and then temporarily stopped. The method for controlling a crane for carrying a suspended load according to any one of claims 1 to 3, wherein: