JP7665376B2 - crane - Google Patents

Description

The present invention relates to a crane.

Conventionally, there is known a crane that includes a suspending part that holds an object by suspending it, a moving part that moves the suspending part horizontally, and a position measuring part that measures the position (see, for example, Patent Document 1). When this crane moves to the target position of the coil to be held, the position measuring part measures the position while the crane is moving. The crane accurately reaches the target position based on the measurement results of the position measuring part.

JP 2019-52019 A

In the above-mentioned crane, the position measurement unit measures the position while the crane is moving, so the measurement accuracy may decrease. As a result, the position accuracy between the object and the hanging part, and the position accuracy between the object's placement position and the hanging part may decrease.

The present invention has been made to solve these problems, and aims to provide a crane that can improve the accuracy of position measurement by the position measurement unit.

The crane according to the present invention comprises a suspending section that holds an object by suspending it, a moving section that moves the suspending section horizontally, and a position measuring section that measures the position. The moving section moves the suspending section to a target position relative to the position where the object to be held is located or the position where the held object is to be lowered, and the position measuring section measures the target position when the suspending section is stopped or when the suspending section is moving at a very slow speed.

According to this crane, the moving unit moves the hanging part to a target position relative to the position where the object to be held is located or the position where the held object is to be lowered. In contrast, the position measurement unit measures the target position when the hanging part is stopped or when the hanging part is moving at a very slow speed. In this way, when the hanging part is stopped or when the hanging part is moving at a very slow speed, the position measurement unit can perform more accurate measurements compared to when the measurement is performed while moving. As a result, the accuracy of position measurement by the position measurement unit can be improved.

The position measurement unit may be provided on a trolley that supports the hanging part. In this case, the position measurement unit can also measure the position of the hanging part. This makes it easier to align the target position with the position of the hanging part.

The position measurement unit may measure the target position and the position of the hanging part simultaneously. In this case, it becomes easier to align the target position and the position of the hanging part.

The position measurement unit may measure the target position when the hanging part is stationary. In this case, the measurement can be performed more accurately than if the position measurement unit were to measure when the hanging part is moving slowly.

When the position measurement unit measures the target position, the moving unit may stop the movement of the hanging unit by setting the speed command to 0, or may reduce the speed command to move at a very slow speed. In this case, the stopped or very slow state can be achieved without using a brake.

When the position measurement unit measures the target position, the movement unit may stop the movement of the hanging part or move it at a very slow speed without using a mechanical brake. In this case, when fine-tuning the position of the hanging part based on the measurement results of the position measurement unit, there is no loss in releasing the brake, so fine adjustments can be made quickly.

The moving unit may move the hanging part to the target position based on a pre-created map of the placement area in which the object is placed. In this case, the moving unit may move the hanging part to an approximate target position before the position measurement unit performs measurement.

The present invention provides a crane that can improve the accuracy of position measurement by the position measurement unit.

FIG. 1 is a schematic front view of a crane according to an embodiment of the present invention. FIG. 1 is a schematic side view of a crane according to an embodiment of the present invention. FIG. 2 is a block diagram showing the configuration of a traveling device. FIG. 2 is a block diagram showing a system configuration of the crane system. FIG. 2 is a conceptual diagram showing the coil yard. 1 is a graph showing a transition of speed. FIG. 4 is a process diagram showing the work process of the crane system. 10 is a flowchart showing a process for creating a 3D map. 11 is a first half of a flowchart showing processing contents in a warehousing operation. 11 is a flowchart showing the second half of the process in a warehousing operation. 11 is a first half of a flowchart showing the processing steps in an operation for rearranging coils in a coil yard.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a schematic front view of a crane 1 according to an embodiment of the present invention. FIG. 2 is a schematic side view of a crane 1 according to an embodiment of the present invention. As shown in FIGS. 1 and 2, the crane 1 is an overhead crane that moves while holding an object, for example, a coil C, which is a steel plate wound into a cylindrical shape. In this embodiment, the crane 1 can store and retrieve the coil C from the coil yard Y, and rearrange the coil C within the coil yard Y (see FIG. 5). Note that the crane 1 is not limited to an overhead crane, and may be a bridge crane, a double-link jib crane, or the like. The object is also not limited to a coil, and may be a slab, a bundled steel bar, or the like.

As shown in FIG. 1, the crane 1 includes a rail 2, a girder 3, a trolley 4, a suspension part 6, a traveling device 7, a traverse device 8, a hoisting device 9, a slewing device 11, an opening and closing device 12, a position measuring unit 13, a monitoring unit 14, and an electrical room 15.

The rail 2 is a member that guides the movement of the hanging part 6 in the running direction D1 via the girder 3 and the trolley 4. The rail 2 is a pair of guide members that are spaced apart from each other in the lateral direction D2 and extend parallel to the running direction D1. The rail 2 is fixed to the ceiling of the building of the coil yard Y. The girder 3 is a member that guides the movement of the hanging part 6 in the lateral direction D2 via the trolley 4. The girder 3 is a pair of guide members that are spaced apart from each other in the running direction D1 (see FIG. 2) and extend parallel to the lateral direction D2 so as to be spanned across the pair of rails 2. The girder 3 can run in the running direction D1 along the rail 2 by the running device 7 described later. The trolley 4 suspends the hanging part 6 while being supported by the girder 3. The trolley 4 can traverse in the lateral direction D2 along the girder 3 by the lateral movement device 8 described later.

The traveling device 7 is a device for traveling the girder 3 along the rail 2. The traveling device 7 has wheels 36 provided on both ends of the girder 3 in the lateral direction D2. As shown in FIG. 3, the wheels 36 are provided with a motor 37 that applies a driving force to the wheels 36 and a brake 38 that applies a braking force. The motor 37 is connected to an inverter 39. The inverter 39 sends a command signal to the motor 37 so that the girder 3 travels at a speed corresponding to the speed command signal. The brake 38 is connected to a brake control unit 40. When the brake control unit 40 sends a signal, the brake 38 is separated from the wheels 36. When the brake control unit 40 stops the signal, the elastic force of the spring provided in the brake 38 presses the brake 38 against the wheels 36.

As shown in FIG. 1, the traverse device 8 is a device for traversing the trolley 4 along the girder 3. The traverse device 8 has wheels 45 attached to the trolley 4. The traverse device 8 also has a motor, brake, inverter, and brake control unit similar to those of the traveling device 7. The traveling device 7 and the traverse device 8 form a moving unit that moves the hanging part 6 in the horizontal direction.

The hanging part 6 holds the coil C, which is the object to be held, by suspending it. In this embodiment, the hanging part 6 has a pair of arms 31 and a claw part 32 provided on each arm part 31 (see FIG. 2). The hanging part 6 is suspended from the trolley 4 by a wire 33. The hanging part 6 is connected to a hoisting device 9 provided on the trolley 4 via the wire 33. Therefore, the hoisting device 9 can raise the hanging part 6 by winding up the wire 33. The arm part 31 is provided so as to sandwich the coil C from both ends. The pair of claw parts 32 are provided at the lower end of each arm part 31, respectively, in a state in which they extend close to each other. When holding the coil C, the claw parts 32 can come out so as to protrude from the arm part 31, and when releasing the holding of the coil C, they can enter so as to be stored in the arm part 31.

The arm portion 31 is provided on both ends of the opening/closing device 12, and is opened and closed by the driving of the opening/closing device 12. The hanging portion 6 is connected to the wire 33 via the swivel device 11. Therefore, the hanging portion 6 can rotate around the wire 33. When the hanging portion 6 holds the coil C, the hoisting device 9 and the swivel device 11 move the hanging portion 6 to lower the claw portion 32 to the position of the through hole of the coil C. In this state, the opening/closing device 12 closes the arm portion 31 to insert the claw portion 32 into the through hole of the coil C. In this state, the hanging portion 6 is wound up by the hoisting device 9 via the wire 33. This allows the hanging portion 6 to suspend and hold the coil C.

The position measurement unit 13 is a device that measures the positions of various objects in the coil yard Y. The position measurement unit 13 is not particularly limited as long as it is a device capable of measurement, and is, for example, composed of a 3D lidar. In addition, the position measurement unit 13 may be composed of an image recognition camera, a 2D lidar, etc. The position measurement unit 13 is provided on the trolley 4 in a state facing downward from the trolley 4. In Figures 1 and 2, the measurement range DE of the position measurement unit 13 is shown by the hatched area range. The measurement range DE of the position measurement unit 13 includes both the coil C and the hanging part 6. Therefore, when the coil C is held by the hanging part 6, the position measurement unit 13 can simultaneously measure the position of the coil C and the position of the hanging part 6. In addition, when the held coil C is lowered, the position measurement unit 13 can simultaneously measure the position at which the coil C is lowered and the position of the hanging part 6. The position measurement unit 13 can also measure the positions of the skids 80 (see Figures 1 and 2) that exist on the coil yard Y and the trailer T. The skids 80 are members that prevent the coils C from rolling when they are placed on the floor surface. This allows the position of the skids 80 to be reflected when creating a 3D map.

When viewed from the running direction D1, the center line CL2 of the position measurement unit 13 is located at a position shifted from the center line CL1 of the hanging part 6 in the lateral direction D2 (see FIG. 1). When viewed from the lateral direction D2, the center line CL2 of the position measurement unit 13 is located at the same position as the center line CL1 of the hanging part 6. As a result, when aligning the coil C and the hanging part 6, only the amount of deviation in the lateral direction D2 needs to be considered.

The monitoring unit 14 is a device for monitoring the situation around the crane 1. The monitoring unit 14 is composed of a remote monitoring camera and the like. The monitoring unit 14 is provided on the trolley 4. The electrical room 15 houses various electrical devices for operating the crane 1. The electrical room 15 houses the inverters for the traveling device 7 and the traverse device 8, the brake control unit, the on-machine control panel 41 described below, the coil position recognition device 42, the wireless communication device 43, and the like.

Next, the system configuration of the entire crane system 100 that controls the crane 1 as described above will be described. FIG. 4 is a block diagram showing the system configuration of the crane system 100. As shown in FIG. 4, the crane system 100 includes a crane 1 and a ground control room 50 that operates the crane 1. The ground control room 50 includes a ground control panel 51, an inventory management computer 52, a higher-level system PC 53, and a remote monitoring monitor 54. The ground control room 50 is provided at a location away from the crane 1, and at a predetermined location in the building of the coil yard Y.

The ground operation panel 51 is a device that transmits various information for operating the crane 1 to the crane 1. The ground operation panel 51 transmits information to the crane 1 via the wireless communication unit 56. The inventory management computer 52 is a device that performs calculations for inventory management of the coils C in the coil yard Y. For example, the inventory management computer 52 calculates the optimal transport route based on coil transport instructions from the upper system PC 53. The upper system PC 53 is a device that issues coil transport instructions such as the supply of coils according to the operating status of the factory. The remote monitoring monitor 54 is a device that monitors the situation around the crane 1 by displaying images captured by the monitoring unit 14.

The crane 1 is equipped with an on-board control panel 41, a coil position recognition device 42, and a wireless communication device 43. The on-board control panel 41 outputs various information necessary for the operation of the crane 1 to each device in the crane 1. The on-board control panel 41 outputs command signals to the traveling device 7, the traverse device 8, the hoisting device 9, the slewing device 11, and the opening and closing device 12 to perform the desired operation. The coil position recognition device 42 is a device for recognizing the position of the coil C based on the measurement results by the position measurement unit 13. The coil position recognition device 42 outputs the recognized position of the coil C to the on-board control panel 41. The wireless communication device 43 is a device for transmitting and receiving information to and from the ground operation room 50 via wireless communication.

Next, the operation of the crane 1 will be described. The traveling device 7 and the traverse device 8 move the hanging part 6 to the target position where the coil C to be held is located or the position where the held coil C is to be lowered based on a command signal from the on-board control panel 41. At this time, the traveling device 7 and the traverse device 8 move the hanging part 6 to the target position based on a 3D map created in advance of the coil yard Y (placement area) where the coil C is located. That is, the on-board control panel 41 refers to the 3D map created in advance and calculates where the coil C to be held is located in the coil yard Y, or where the held coil C is to be placed in the coil yard Y. Then, the on-board control panel 41 outputs a command signal to the traveling device 7 and the traverse device 8 to move to the target position calculated based on the 3D map. The 3D map is created by the crane 1 moving the entire coil yard Y while performing measurements with the position measurement unit 13, thereby grasping the position of each coil C in the coil yard Y (see, for example, FIG. 5). The 3D map is created, for example, before and after the start of a day's work at coil yard Y. This allows the 3D map to be updated periodically.

When the traveling device 7 and the traverse device 8 reach the target position based on the 3D map (when they reach a position just before arriving), they stop the movement of the suspended part 6 or put the suspended part 6 into a slow speed state. Here, "stopped" means that the speed is 0. Also, a slow speed state means that the suspended part 6 moves at a speed between 0% and 10% of the rated speed, which is 100%.

The position measurement unit 13 measures the target position when the hanging part 6 is stopped or when the moving speed of the hanging part 6 is very slow. That is, when the traveling device 7 and the traverse device 8 arrive at the target position based on the 3D map, a horizontal positional deviation may occur between the actual position of the hanging part 6 and the coil presence position where the coil C to be transported actually exists or the landing position where the held coil C is to be landed (the target position for landing of the coil C). Therefore, by measuring the actual hanging part 6 and the target position, the position measurement unit 13 can hold the coil C (landing of the coil C) in a state where the deviation is eliminated. Measuring the target position means that the position measurement unit 13 measures from above the space where the coil C to be transported exists or the coil C to be held is to be landed. When the coil C exists at the target position, the position measurement unit 13 acquires information such as the outer diameter and width of the coil C, and the coil position recognition device 42 calculates the center position of the coil C based on the information. If the coil C is not present at the target position, the position measurement unit 13 acquires the shape of the mounting table on which the coil C is placed, and the coil position recognition device 42 calculates the center position of the mounting table based on the shape. The mounting table is, for example, a skid 80 (see Figures 1 and 2), and is provided at all addresses on the trailer T and in the coil yard Y. Note that the target position is not particularly limited to a specific location as long as the coil presence position where the coil C is present and the landing position where the coil C is to land can be grasped. For example, the coil position recognition device 42 may treat the center position of the coil C and the center position of the mounting table as the target position, but may also treat a point, line, two-dimensional area, three-dimensional area, etc. calculated based on these center positions as the target position.

If there is a deviation between the actual center position of the hanging part 6 in the horizontal direction and the center position of the coil C to be transported, the on-machine control panel 41 controls to fine-adjust the position of the hanging part 6 so as to eliminate the deviation between the center position of the hanging part 6 and the center position of the coil C. If there is a deviation between the actual center position of the hanging part 6 in the horizontal direction and the center position of the mounting table on which the coil C is to be placed, the on-machine control panel 41 controls to fine-adjust the position of the hanging part 6 so as to eliminate the deviation between the center position of the hanging part 6 and the center position of the mounting table. In this way, the on-machine control panel 41 controls the traveling device 7, the traverse device 8, the turning device 11, and the opening and closing device 12 to reach the target position based on the 3D map, and after the hanging part 6 stops or moves at a slow speed, fine-adjusting the hanging part 6 may be referred to as target position complementation. However, the control content for eliminating the deviation between the hanging part 6 and the coil C and the deviation between the hanging part 6 and the mounting table is not particularly limited, and any control method may be appropriately adopted.

When the position measurement unit 13 measures the target position with the hanging part 6 stopped, the traveling device 7 and the traverse device 8 stop the movement of the hanging part 6 by setting the speed command to 0. Also, when the position measurement unit 13 measures the target position with the hanging part 6 moving at a very slow speed, the speed command is reduced to put the hanging part 6 in a very slow state. At this time, the traveling device 7 and the traverse device 8 stop the movement of the hanging part 6 or set the movement speed to a very slow speed without using a mechanical brake (brake 38 in Figure 3).

Specifically, the on-machine control panel 41 sets the target position to which the suspending part 6 is to be moved based on the 3D map, and sets the movement amount and movement speed of the traveling device 7 and the traverse device 8 so that the suspending part 6 can move to the target position. When heading toward the target position, the on-machine control panel 41 issues a speed command to move at a normal speed (for example, see A in FIG. 6). When the suspending part 6 approaches the target position, the on-machine control panel 41 issues a speed command to decelerate (see B in FIG. 6) and issues a speed command to move at a slow speed (see C in FIG. 6). When the target position is reached, the on-machine control panel 41 sets the speed command to 0 (see D in FIG. 6). The position measurement unit 13 detects the position in either state C or D in FIG. 6. Note that when the position measurement unit 13 measures the position in state D, the state may be changed directly from state B to state D without providing the region C. At this time, the on-board control panel 41 controls the traveling device 7 and the traverse device 8 to decelerate only by reducing the speed command, and controls so that the brakes are not applied to both the traveling device 7 and the traverse device 8. As a result, when the hanging part 6 is stopped or moving slowly for measurement by the position measurement unit 13, the brakes are not applied to both the traveling device 7 and the traverse device 8.

Next, the work process of the crane system 100 will be described with reference to FIG. 7. FIG. 7 is a process diagram showing the work process of the crane system 100. First, the crane system 100 creates a 3D map of the coil yard Y (step S10). Next, when the trailer T loaded with the coil C arrives at the trailer parking area TE (see FIG. 5), the crane system performs a storage operation to store the coil C from the trailer T to the coil yard Y (step S20). After storing the coil C, the crane system 100 performs a rearrangement operation of the coil C within the coil yard Y as necessary (step S30). Next, the crane system 100 performs an unloading operation to remove the coil C to be unloaded from the coil yard Y and load it onto the trailer T (step S40).

Next, referring to FIG. 8, the process for creating a 3D map will be described. As shown in FIG. 8, when the flow for creating a 3D map starts, the crane system 100 executes a start process (step S110). In step S110, a push operation to start automatic operation is performed on the ground operation panel 51, and the on-machine control panel 41 determines whether or not a transport command has been received from the ground operation panel 51. When the on-machine control panel 41 receives the transport command, it starts automatic operation. In addition, the on-machine control panel 41 determines whether the height of the hanging part 6 is high enough to create a 3D map, and if it is low, it controls the hoisting device 9 to hoist the hanging part 6.

Next, the crane system 100 moves the suspension unit 6 to an initial position for creating a 3D map (step S120). In step S120, the on-board control panel 41 sets target values for each of the traveling device 7, traverse device 8, slewing device 11, and opening/closing device 12 to values corresponding to the initial positions, and repeats each operation until the target value is reached. When each device reaches its target value, the on-board control panel 41 transmits to the ground operation panel 51 a message indicating that movement to the initial position has been completed.

Next, the crane system 100 starts creating a 3D map by measuring the coil yard Y with the position measurement unit 13, and moves the hanging unit 6 (step S130). In step S130, the on-machine control panel 41 moves the hanging unit 6 along the path required to create the 3D map and reaches the target position. The path is set to pass through all the addresses of the coil yard Y, and the position measurement unit 13 performs measurements at each address similar to the measurement of the target position described above. The coil position recognition device 42 may calculate the center position of the coil C or the center position of the skid 80 at each address. The on-machine control panel 41 repeats the operations of the traveling device 7 and the traverse device 8 until the target position is reached. In this manner, spatial information for each address of the coil yard Y is acquired.

Next, the crane system 100 checks whether the 3D map is complete (step S140). In step S140, the on-board control panel 41 determines whether there is a problem with the 3D map. If the measurement results for all addresses have not been obtained, the process returns to step S120, and the traveling device 7 and the traverse device 8 operate to return to the initial position. If it is determined in step S140 that there is no problem with the 3D data, the crane system 100 transmits a completion message to the ground operation panel 51 and performs the end process of the 3D map creation (step S150). In step S150, the on-board control panel 41 determines whether to end the automatic operation. If the automatic operation stop button is pressed on the on-board control panel 41, the on-board control panel 41 ends the automatic operation. This completes the flow of the 3D map creation shown in FIG. 8.

Next, referring to FIG. 9 and FIG. 10, the process contents of the storage operation when the coil C is stored from the trailer T to the coil yard Y will be described. As shown in FIG. 9, the crane system 100 executes a start process (step S210). In step S210, the same process as in step S110 is performed. Next, the crane system 100 moves the hanging part 6 to the trailer T (step S220). In step S220, the on-machine control panel 41 sets the position of the coil C to be transported placed on the trailer T stopped in a predetermined trailer stopping area TE as the target position. When multiple coils C are loaded on the trailer T, the loading position information of the coil C to be transported on the trailer T may be obtained from the upper system PC53. The on-machine control panel 41 moves the hanging part 6 by repeating the operations of the traveling device 7, the traverse device 8, the turning device 11, and the opening and closing device 12 until the target value corresponding to the target position is reached. When each device reaches its target value, the on-board control panel 41 transmits a message to the ground control panel 51 indicating that movement to the target position has been completed.

Here, when the suspending part 6 reaches the target position of the trailer T (or reaches just before the target position), the crane system 100 performs a process of stopping the suspending part 6 (step S230). In step S230, the on-machine control panel 41 stops the suspending part 6 by sending a signal with a speed command of 0 to the traveling device 7 and the traverse device 8. When the suspending part 6 stops, the position measurement unit 13 measures the position of the coil on the trailer T and obtains the amount of deviation between the center position of the coil C of the actual transport target in the horizontal direction and the position of the suspending part 6 (step S240). The crane system 100 refers to the coil position measurement result and determines whether there is a problem with the position measurement of the coil C (step S250). If it is determined in step S250 that there is a problem with the position measurement of the coil C, the automatic operation is stopped (step S260). On the other hand, if it is determined in step S250 that there is no problem with the position measurement of the coil C, the crane system 100 performs target position complementation (step 270). In step 270, the crane system 100 fine-tunes the position of the suspending part 6 so as to eliminate the misalignment between the suspending part 6 obtained in step 240 and the center position of the coil C to be transported, and determines whether or not the target position complement has been completed. When the target position complement is completed, the center position of the coil C to be transported in the horizontal direction and the suspending part 6 coincide. If it is determined in step S270 that the target position complement has not been completed, the process returns to step S220, and the traveling device 7 and the traverse device 8 operate to slightly move the suspending part 6 so that the center position of the coil C to be transported in the horizontal direction and the position of the suspending part 6 coincide.

When it is determined in step S270 that the target position completion is completed, the crane system 100 executes a process to hold the coil C on the trailer T (step S280). In step S280, the on-machine control panel 41 controls the hoisting device 9 to lower the hanging part 6. The on-machine control panel 41 also determines whether or not the hanging part 6 has been run over. If it is determined that the run over has occurred, the automatic operation is stopped. Next, the on-machine control panel 41 aligns the claw part 32 of the hanging part 6 with the position of the through hole of the coil C to be held. If the center is found, the hanging part 6 extends the claw part 32 to make it possible to insert the hanging part 6 into the through hole of the coil C. Then, the on-machine control panel 41 controls the opening and closing device 12 to close the arm part 31. When the on-machine control panel 41 detects that the hanging part 6 has gripped the coil C, it controls the hoisting device 9 to wind up the hanging part 6 together with the coil C and raise it to the conveying height position.

As shown in FIG. 10, the crane system 100 then receives destination information for the coil C from the host system PC53, determines the destination by setting it as the target position, and compares the target position with the 3D map (step S310). In step S310, if another coil already exists on the 3D map at the target landing position of the held coil C in the coil yard Y, the automatic operation ends.

Next, the crane system 100 moves the suspending part 6 holding the coil C to the target position set in step S310 (step S320). In step S320, the on-machine control panel 41 sets target values corresponding to the target positions for each of the traveling device 7 and the traverse device 8, and repeats each operation until the target values are reached. Next, when the suspending part 6 reaches the target position of the coil yard Y (or when it reaches just before the target position), the crane system 100 performs a process to stop the suspending part 6 (step S330). In step S330, the same process as in step S230 is performed. When the suspending part 6 stops, the position measurement unit 13 measures the landing position where the held coil C will land from above, and the coil position recognition device 42 calculates the center position of the skid 80 from the measurement result (step S340). The crane system 100 determines whether or not the target position complement, which fine-tunes the position of the suspending part 6 to eliminate the misalignment between the suspending part 6 and the center position of the skid 80, has been completed (step S350). If the coil shape is detected by the measurement of the position measurement unit 13 and it is determined that another coil C is stored at the landing position, the automatic operation is stopped.

Next, the crane system 100 lands the coil C on the coil yard Y (step S360). In step S360, the on-machine control panel 41 controls the hoisting device 9 to wind down the suspending part 6. The on-machine control panel 41 also determines whether the suspending part 6 has been run over using a limit switch or load meter provided on the claw part 32. If it is determined that the suspending part 6 has run over, the automatic operation is stopped. The on-machine control panel 41 also determines whether the coil C has been landed on the coil C, and if it is determined that the coil C has not been landed on the coil C, the operation of winding down is repeated. If the coil C has been landed on the coil C, the on-machine control panel 41 controls the opening and closing device 12 to open the arm part 31. The on-machine control panel 41 then performs an operation of storing the claw part 32 of the suspending part 6 in the arm part 31. When the claw portion 32 enters the arm portion 31, the on-machine control panel 41 controls the hoisting device 9 to hoist the hanging portion 6 and raise it to the transport height. Next, the crane system 100 performs the end process of the warehousing operation (step S370). In step S370, the same process as in step S150 is performed. With the above, the warehousing operation flow shown in Figures 9 and 10 is completed.

Next, referring to FIG. 11, the process of rearranging the coil C in the coil yard Y will be described. As shown in FIG. 11, the crane system 100 executes a start process (step S400). In step S400, the same process as in step S110 is performed. The crane system 100 determines the coil C to be rearranged and compares the target position with the 3D map (step S410). Next, the crane system 100 moves the suspending part 6 to the target coil C (step S420). In step S420, the on-board control panel 41 repeats each operation of the traveling device 7, the traverse device 8, the slewing device 11, and the opening and closing device 12 until the target value corresponding to the target position is reached. When each device reaches the target value, the on-board control panel 41 transmits to the ground operation panel 51 that the movement to the target position has been completed.

Here, when the suspending part 6 reaches the target position of the target coil C (or reaches just before the target position), the crane system 100 performs a process of stopping the suspending part 6 (step S430). In step S430, the same process as in step S230 is performed. When the suspending part 6 stops, the position measurement unit 13 performs position measurement of the target coil C and obtains the amount of deviation between the actual center position of the target coil C in the horizontal direction and the position of the suspending part 6 (step S440). The crane system 100 refers to the coil position measurement result and determines whether there is a problem with the position measurement of the coil (step S450). If it is determined in step S450 that there is a problem with the position measurement of the coil C, the automatic operation is stopped (step S460). On the other hand, if it is determined in step S450 that there is no problem with the position measurement of the coil C, the crane system 100 performs target position complementation (step S470). In step S470, the crane system 100 fine-tunes the position of the suspending part 6 so as to eliminate the misalignment between the suspending part 6 acquired in step S440 and the center position of the coil C to be transported, and determines whether or not the target position complement has been completed. When the target position complement is completed, the center position of the coil C to be transported in the horizontal direction and the suspending part 6 coincide. If it is determined in step S470 that the target position complement has not been completed, the process returns to step S420, and the traveling device 7 and the traverse device 8 operate to slightly move the suspending part 6 so that the center position of the coil C to be transported in the horizontal direction and the position of the suspending part 6 coincide.

When it is determined in step S470 that the target position complement is complete, the crane system 100 executes a process to hold the target coil C (step S480). In step S480, the same process as in step S280 is performed. The crane system 100 then transports the held coil C to the destination position in the coil yard Y. Note that the subsequent process is similar to the process shown in FIG. 10.

For the unloading operation of holding the coil C in the coil yard Y and loading it onto the trailer T, when holding the coil C in the coil yard Y, a control process similar to that shown in FIG. 11 is executed. When loading the held coil C onto the trailer T, a control process similar to that shown in FIG. 10 is executed, except that the target position is the position of the trailer T instead of the landing position of the coil yard Y.

Next, we will explain the function and effect of the crane 1 according to this embodiment.

According to the crane 1 of this embodiment, the traveling device 7 and the traverse device 8 move the suspending part 6 to a target position where the coil C to be held is located, or where the held coil C is to be lowered. In response to this, the position measurement unit 13 measures the target position when the suspending part 6 is stopped or moving very slowly. In this way, when the suspending part 6 is stopped or moving very slowly, the position measurement unit 13 can perform more accurate measurements than when measuring while moving. As a result, the accuracy of position measurement by the position measurement unit 13 can be improved.

The position measurement unit 13 may be provided on the trolley 4 that supports the hanging part 6. In this case, the position measurement unit 13 can also measure the position of the hanging part 6. In this case, it becomes easier to align the target position with the position of the hanging part 6.

The position measurement unit 13 may simultaneously measure the target position and the position of the hanging part 6. In this case, it becomes easier to align the target position with the position of the hanging part 6.

The position measurement unit 13 may measure the target position when the hanging part 6 is stopped. In this case, the measurement can be performed more accurately than when the position measurement unit 13 measures when the hanging part 6 is moving slowly.

When the position measurement unit 13 measures the target position, the traveling device 7 and the traversing device 8 may stop the movement of the hanging part 6 by setting the speed command to 0, or may reduce the speed command to make the movement speed very slow. In this case, the stopped or very slow state can be achieved without using mechanical brakes.

When the position measurement unit 13 measures the target position, the traveling device 7 and the traverse device 8 may stop the movement of the hanging part 6 or slow down the movement speed without using mechanical brakes. In this case, when fine-tuning the position of the hanging part 6 based on the measurement results of the position measurement unit 13, there is no loss in releasing the brake, so fine adjustments can be made quickly.

The traveling device 7 and the traverse device 8 may move the hanging part 6 to the target position based on a pre-created map of the coil yard Y where the coil C is arranged. In this case, the traveling device 7 and the traverse device 8 can move the hanging part 6 to the approximate target position before the position measurement unit 13 performs measurement.

The present invention is not limited to the above-described embodiments.

For example, the configurations of the crane and crane system described above are merely examples and may be modified as appropriate without departing from the spirit and scope of the present invention.

The position measurement unit was attached to the trolley, but the attachment location is not particularly limited and it may be attached to a location other than the trolley.

1...Crane, 4...Trolley, 6...Suspension part, 7...Travel device (moving part), 8...Traverse device (moving part), 13...Position measurement part.

Claims (8)

A hanging part that holds an object by hanging it;
A moving unit that moves the hanging part in a horizontal direction;
A position measurement unit that measures a position,
The moving unit has a traveling device and a traverse device, and moves the hanging unit to a target position relative to a position where the object to be held is located or a position where the held object is to be lowered,
The position measurement unit measures the target position while the hanging part is stopped,
The traveling device and the traverse device stop the movement of the hanging part without using a mechanical brake,
A crane in which when the suspension part is stopped for measurement by the position measurement part, mechanical brakes are not activated in the traveling device and the traverse device. The crane according to claim 1, wherein the position measurement unit is provided on a trolley that supports the hanging part. The crane according to claim 1 or 2, wherein the position measurement unit simultaneously measures the target position and the position of the hanging part. The crane according to any one of claims 1 to 3 , wherein when the position measurement unit measures the target position, the movement unit stops the movement of the hanging unit by setting a speed command to 0. The crane according to any one of claims 1 to 4 , wherein the moving unit moves the suspending unit to the target position based on a pre-created map of a placement area in which the object is placed. A crane as described in any one of claims 1 to 5, wherein after measurement by the position measurement unit, the position of the hanging part is adjusted so as to eliminate a deviation between the position of the object and the position of the hanging part or a deviation between the target position and the position of the hanging part . the object is a coil,
acquiring a deviation between a center position of the coil and a position of the hanging part based on a measurement result of the position measurement unit;
The crane according to claim 6 , wherein the position of the hanging part is adjusted to eliminate a misalignment between a center position of the coil and a position of the hanging part. calculating a center position of a skid that is a member for preventing the coil from rolling based on a measurement result of the position measurement unit;
The crane of claim 7 , wherein the position of the hanging part is adjusted to eliminate any misalignment between the hanging part and a center position of the skid.

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