JP7445545B2 - Crane and its control method - Google Patents

Description

TECHNICAL FIELD The present invention relates to a crane equipped with a hanging device suspended from a trolley by a wire rope, and a method for controlling the crane, and more particularly to a crane that can accurately position the hanging device and a method for controlling the same.

Various methods have been proposed for aligning containers to be handled using a portal crane (for example, see Patent Document 1). Patent Document 1 discloses a method of performing positioning while suppressing shaking of a container by suppressing the acceleration and maximum speed of a portal crane that is run during positioning.

The gantry crane itself may be tilted due to the inclination of the running surface on which the gantry crane runs, the deviation of the center of gravity of the gantry crane due to the weight of the container, or the drop in air pressure of the gantry crane's tires. there were. If the gantry crane was tilted, there was a problem in which the container would shift horizontally as it descended. It was difficult to align the container accurately.

When moving a gantry crane or trolley to correct the misalignment of a lowered container, there was a problem in which the container would shake. Because containers were placed on the floor after waiting for the shaking to stop, cargo handling efficiency was decreasing.

Japanese Patent Application Publication No. 2002-012389

The present invention has been made in view of the above problems, and an object thereof is to provide a crane and a control method thereof that can accurately align the position of a hanging tool.

The crane to achieve the above purpose is
a leg structure having a girder extending in the transverse direction; a plurality of traveling devices installed at the lower end of the leg structure and configured to be movable along a running direction perpendicular to the transverse direction; The crane includes a trolley configured to be movable in the transverse direction along the girder, and a hanging device suspended from the trolley by a wire rope, wherein the trolley has a central axis in at least one of the transverse direction or the traveling direction. an adjustment mechanism for controlling the inclination of the pneumatic tire, each of the traveling devices having a pneumatic tire, and the adjustment mechanism comprising a gas supply source that supplies gas to the pneumatic tire; It is characterized by comprising a communication port through which gas can enter and exit by communicating the inside and outside of the container .

The crane control method for achieving the above purpose consists of a leg structure having a girder extending in the traverse direction, and a leg structure installed at the lower end of the leg structure that extends in the traveling direction perpendicular to the traverse direction. A method for controlling a crane comprising a plurality of traveling devices configured to be movable along the girder, a trolley configured to be movable in a lateral direction along the girder, and a hanging device suspended from the trolley by a wire rope. The above-mentioned hanging tool is configured to align the hanging tools suspended from the trolley by adjusting the inclination of the trolley with at least one of the transverse direction or the traveling direction as a central axis, and The traveling device has a pneumatic tire, and the pneumatic tire is deformed by adjusting the pressure inside the pneumatic tire, thereby adjusting the inclination of the trolley.

According to the present invention, by adjusting the inclination of the trolley, it is possible to align the hanging tool suspended from the trolley with a wire rope. This is advantageous for positioning the hanging tool with high precision.

It is an explanatory view illustrating a gate type crane in perspective. It is an explanatory view illustrating an adjustment mechanism. FIG. 2 is an explanatory diagram illustrating a state in which a portal crane is tilted due to an inclination of a running surface. It is an explanatory view illustrating a state where a girder is adjusted horizontally by an adjustment mechanism. FIG. 3 is an explanatory diagram illustrating a state in which the position of the hanging tool is shifted in the transverse direction with respect to the target position. FIG. 3 is an explanatory diagram illustrating a state in which the girder is tilted with the traveling direction as the central axis by the adjustment mechanism. FIG. 3 is an explanatory diagram illustrating a state in which the position of the hanging tool is shifted in the traveling direction with respect to the target position. FIG. 3 is an explanatory diagram illustrating a state in which the girder is tilted with the transverse direction as the central axis by the adjustment mechanism. It is an explanatory view illustrating a modification of an adjustment mechanism. It is an explanatory view illustrating a modification of an adjustment mechanism.

DESCRIPTION OF THE PREFERRED EMBODIMENTS A crane and its control method will be described below based on the embodiment shown in the drawings. In the figure, the traveling direction of the crane is indicated by an arrow y, the traverse direction perpendicular to this traveling direction is indicated by an arrow x, and the vertical direction is indicated by an arrow z.

As illustrated in FIG. 1, the crane 1 includes a leg structure 2 and a plurality of traveling devices 3 installed at the lower end of the leg structure 2. The leg structure 2 includes a girder 4 extending in the transverse direction x, and columnar members 5 extending downward from both ends of the girder 4 in the transverse direction x.

In this embodiment, the leg structure 2 includes a pair of girders 4 and four columnar members 5 that support the girders 4. Four traveling devices 3 are installed at the lower end of the leg structure 2. Each traveling device 3 has two pneumatic tires 6. The traveling device 3 can cause the crane 1 to travel along the traveling direction y.

The crane 1 includes a trolley 7 configured to be movable in the transverse direction x along the girder 4, and a hanging tool 9 suspended from the trolley 7 by a wire rope 8. The hanging tool 9 is composed of, for example, a spreader that grips the container 10.

The crane 1 of the present invention is not limited to the gantry crane illustrated in FIG. The crane 1 only needs to have at least a girder 4 and a trolley 7, and may be configured as a quay crane or an overhead crane, for example.

As illustrated in FIG. 2, the crane 1 includes an adjustment mechanism 11 that controls the inclination of the trolley 7 with at least one of the traverse direction x or the travel direction y as the central axis. In this embodiment, the adjustment mechanism 11 includes a gas supply source 12 installed in the leg structure 2 and a communication port 13 that communicates the inside and outside of the pneumatic tire 6 to allow gas to enter and exit. The gas supply source 12 and the communication port 13 are connected by a pipe 14. In this embodiment, the communication ports 13 of each pneumatic tire 6 are connected to the gas supply source 12 via a pipe 14 in parallel to each other.

The gas supply source 12 includes a tank or a compressor filled with pressurized gas. The gas supply source 12 can be arranged inside the machine room 15 of the crane 1 . In FIG. 2, the gas supply source 12 is shown by a broken line for explanation. The location where the gas supply source 12 is installed is not limited to the above, but can be installed at any location on the crane 1 such as the columnar member 5 or the traveling device 3.

The communication port 13 is configured to communicate with the inside of the pneumatic tire 6 from the side surface of the axle of the pneumatic tire 6. A discharge valve 16 is connected to the communication port 13 via a pipe 14. By opening the discharge valve 16, the gas inside the pneumatic tire 6 is discharged into the atmosphere. By controlling the opening and closing of the discharge valve 16, it is possible to reduce the pressure inside the pneumatic tire 6.

A supply valve 17 is disposed on a pipe 14 that connects the gas supply source 12 and the communication port 13 . By opening the supply valve 17, gas is supplied from the gas supply source 12 to the inside of the pneumatic tire 6. By controlling the opening and closing of the supply valve 17, the pressure inside the pneumatic tire 6 can be increased.

The configuration of the adjustment mechanism 11 is not limited to the above, but may be any configuration that can control the increase/decrease of the pressure inside the pneumatic tire 6. The discharge valve 16 and the supply valve 17 may be configured as one valve. For example, by operating the compressor that constitutes the gas supply source 12 and opening the supply valve 17, the pressure inside the pneumatic tire 6 is increased, and by stopping the compressor and opening the supply valve 17, the air pressure is increased. A configuration may be adopted in which the pressure inside the inner tire 6 is reduced.

It is desirable that the adjustment mechanism 11 has a configuration that can actively control the internal pressure of all the pneumatic tires 6. The adjustment mechanism 11 may have a configuration that can actively control the internal pressure of some of the pneumatic tires 6 among the plurality of pneumatic tires 6.

The gas supplied to the pneumatic tire 6 by the gas supply source 12 may be a gas composed of other components such as nitrogen gas in addition to air. The adjustment mechanism 12 may include a compressor that constitutes the gas supply source 12, and a control section 18 that controls opening and closing of the discharge valve 16 and the supply valve 17. In this case, the control unit 18 is connected to a compressor or the like via a wired or wireless signal line. A control mechanism that controls the traveling of the crane 1 and the like may be configured to be used as the control section 18.

The adjustment mechanism 11 may have the same number of gas supply sources 12 as the pneumatic tires 6, and one gas supply source 12 may be connected to one pneumatic tire 6 through a pipe 14, respectively.

A configuration in which the adjustment mechanism 11 does not include the gas supply source 12 may also be used. A configuration may be adopted in which gas is moved from one pneumatic tire 6 to the other pneumatic tire 6 by controlling the opening and closing of the supply valve 17 and the like installed in the pipe 14. The discharge valve 16 and the supply valve 17 may be configured with a check valve whose opening/closing is controlled, or may be configured with a valve whose opening degree can be controlled.

As illustrated in FIG. 3, the running surface 19 of the crane 1 may be inclined. In FIG. 3, the running surface 19 is inclined with the height varying along the transverse direction x. As the traveling surface 19 inclines, the crane 1 also inclines. The girder 4 and trolley 7 of the crane 1 are in a state of inclination with the traveling direction y as the central axis. When the crane 1 tilts, the load generated on the pneumatic tire 6 on the lower side increases, which may cause the pneumatic tire 6 to collapse and the tilt of the crane 1 to increase. In FIG. 3, for the sake of explanation, the transverse direction x in a coordinate system in which the vertical direction z coincides with the vertical direction is shown by a broken line. Further, in a coordinate system centered on the crane 1, a perpendicular line P perpendicular to the girder 4 is shown by a chain line. The perpendicular line P shown passes through the trolley 7.

When positioning the trolley 7 as illustrated in FIG. 3, the trolley 7 is moved to a position directly above the target position where the container 10 is scheduled to be placed in a coordinate system centered on the crane 1. At this time, the perpendicular line P passing through the trolley 7 is in a state where it coincides with the target position. For example, when the crane 1 is remotely operated by an operator, an image from a camera installed on the trolley 7 shows the target position directly below the trolley 7.

When the container 10 is lowered after the positioning of the trolley 7 is completed, the container 10 shifts from the perpendicular P in the transverse direction x. The hanging tool 9 is suspended from the trolley 7 by passing the wire rope 8 around a plurality of sheaves installed on the upper surface of the hanging tool 9. Therefore, the hanging tool 9 that grips the container 10 descends from the trolley 7 along the vertical direction. The container 10 does not descend along the perpendicular line P and deviates from the target position. When the image from the camera installed on the trolley 7 is displayed on the remote monitor, the operator who is operating the crane 1 while checking this monitor can move the container 10 held by the lifting tool 9 directly below. I believe they are working on lowering it. However, as the container 10 descends, it moves in the traverse direction x and is no longer aligned with the target position.

In such a case, gas is supplied by the adjustment mechanism 11 to the pneumatic tire 6 on the lower side of the slope of the running surface 19. Further, the adjustment mechanism 11 discharges gas from the pneumatic tire 6 located above the slope of the running surface 19. By adjusting the pressure inside the pneumatic tire 6 using the adjustment mechanism 11 as illustrated in FIG. 4, the girder 4 is placed in a horizontal state that coincides with the traverse direction x. Accordingly, the moving direction of the trolley 7 also becomes a horizontal state that coincides with the traversing direction x. That is, the adjustment mechanism 11 adjusts the inclination of the girder 4 and the trolley 7 with the traveling direction y as the central axis.

Since the girder 4 and the like are in a horizontal state, the perpendicular line P of the girder 4 is parallel to the vertical direction. When the container 10 is lowered, the container 10 descends along the perpendicular line P without moving in the transverse direction x. When the trolley 7 is moved to a position directly above the target position when the girder 4 and the like are in a horizontal state, the container 10 held by the hanging tool 9 can be accurately caused to reach the target position. This is advantageous for positioning the trolley 7 and the hanging tool 9 with high precision.

The case where only the hanging tool 9 not gripping the container 10 is moved to the target position is similar to the above, and the positioning of the hanging tool 9 can be performed with high precision.

A configuration may be adopted in which an inclinometer is installed on at least one of the girder 4 or the trolley 7. It is advantageous for the adjustment mechanism 11 to accurately bring the trolley 7 and the like into a horizontal state.

When operating the crane 1 remotely, there may be a configuration in which the movement of the crane 1 and the positioning by the traversal movement of the trolley 7 are automatically controlled, and the operator only operates the lifting tool 9 up and down. The pressure inside the pneumatic tire 6 may be adjusted by the adjustment mechanism 11 while the crane 1 is traveling and the trolley 7 is automatically controlled. When the operator lowers the hanging tool 9 by remote control, the girder 4 and the like can be in a horizontal state and the positioning of the trolley 7 has already been completed. In other words, the hanging tool 9 is aligned with high precision. Since no positional shift occurs due to the lowering of the hanging tool 9 and there is no need to correct the position of the hanging tool 9, the operator can complete the cargo handling work by simply raising and lowering the hanging tool 9. This is advantageous for improving the cargo handling efficiency of the crane 1.

The adjustment mechanism 11 can also be used when the running surface 19 is horizontal and the position of the hanging tool 9 is deviated from the target position, as illustrated in FIG. Even after completing the alignment of the trolley 7, there may be cases where the position of the container 10 needs to be slightly adjusted. If the trolley 7 is moved again and the positioning is performed, the hanging tool 9 suspended from the trolley 7 may shake, resulting in a decrease in cargo handling efficiency.

As illustrated in FIG. 6, the adjustment mechanism 11 discharges the gas inside the pneumatic tire 6 on one side in the transverse direction x, thereby deforming the pneumatic tire 6 so as to crush it. Due to the deformation of the pneumatic tire 6, the girder 4 tilts with the traveling direction y as the central axis. The hanging tool 9 moves in the direction in which the girder 4, which is tilted in the transverse direction x, is lowered. Shaking occurring in the hanging tool 9 can be suppressed more than when positioning is performed by moving the trolley 7 again. This is advantageous for performing minute alignment.

By actively tilting the trolley 7 using the adjustment mechanism 11, minute positioning of the lowered hanging tool 9 can be performed. Even if the running surface 19 is inclined, the adjustment mechanism 11 can similarly perform minute positioning of the hanging tool 9.

As illustrated in FIG. 7, even if the position of the hanging tool 9 is deviated from the target position in the traveling direction y, the adjustment mechanism 11 can be used in the same manner as described above. As illustrated in FIG. 8, by adjusting the pressure inside the pneumatic tires 6 arranged along the traveling direction y, the inclination of the trolley 7 about the traversing direction x as the central axis can be adjusted. For example, the inclination of the trolley 7 can be adjusted by discharging the gas inside the pneumatic tire 6 on the right side in FIG. 8 and supplying the gas inside the pneumatic tire 6 on the left side in FIG. The inclination of the trolley 7 may be adjusted by controlling only the pressure of one of the pneumatic tires 6 on the right side or the left side in FIG.

When positioning is performed by moving the crane 1 in the traveling direction y, minute adjustments are extremely difficult. For example, when the position of the hanging tool 9 is deviated from the target position by 5 cm in the traveling direction y, it is difficult to align the position by moving the stopped crane 1 5 cm and applying the brake. Further, there was a problem in that the hanging tool 9 swayed along the traveling direction y. For this reason, conventionally, the crane 1 has been moved once by a large distance, such as 5 meters, and then moved toward the target position again to perform positioning by controlling the timing of applying the brakes. In other words, in the past, the positioning of crane 1 had to be redone.

On the other hand, when the adjustment mechanism 11 aligns the position of the hanging tool 9 in the traveling direction y, it is possible to suppress the vibration that occurs in the hanging tool 9, and to make minute adjustments to the position of the hanging tool 9 in a short time. Become.

Since the pressure inside the pneumatic tire 6 can be controlled by the adjustment mechanism 11, it is also possible to avoid a problem in which the pressure in the pneumatic tire 6 decreases due to aging. With the configuration including the adjustment mechanism 11, a state similar to that in which the internal pressure of the pneumatic tire 6 is constantly monitored is achieved. Maintenance work to check the pressure of a plurality of pneumatic tires 6 becomes unnecessary.

The adjustment mechanism 11 is not limited to a configuration that adjusts the internal pressure of the pneumatic tire 6. It is sufficient to have a configuration that can control the inclination of the trolley 7 with at least one of the transverse direction x or the running direction y as the central axis. As illustrated in FIG. 9 , the adjustment mechanism 11 may include a lifting section 20 that moves at least a portion of the trolley 7 in the vertical direction z.

In this embodiment, the elevating parts 20 are installed at the four corners of the trolley 7 when viewed from above. The elevating section 20 is composed of, for example, a hydraulic cylinder, an air cylinder, or an electric actuator. The elevating part 20 is installed on the lower surface of the trolley 7, and has a configuration in which when extended, it comes into contact with the girder 4 and lifts the trolley 7 upward. By independently controlling the expansion and contraction of the four elevating sections 20, the trolley 7 can be tilted in both the transverse direction x and the running direction y.

Since the adjustment mechanism 11 constituted by the lifting section 20 is configured to directly tilt the trolley 7, the tilt of the trolley 7 can be adjusted with a relatively small power. Moreover, since it becomes possible to tilt the trolley 7 in a relatively short time, the response speed of positioning of the hanging tool 9 by the adjustment mechanism 11 can be improved.

As illustrated in FIG. 10, the elevating section 20 may have a configuration in which a motor and a crank 21 rotated by the motor are combined. As the crank 21 rotates, the elevating section 20 expands and contracts in the vertical direction z. When the crank 21 is rotated from the state shown on the left side of FIG. 10, the elevating section 20 extends as shown on the right side of FIG. By rotating the crank 21, a part of the trolley 7 can be moved in the vertical direction z.

When the adjustment mechanism 11 is not configured to adjust the internal pressure of the pneumatic tire 6, such as when it is configured with the elevating section 20, the traveling device 3 may be configured without the pneumatic tire 6. For example, the traveling device 3 can be configured to have wheels made of iron.

The elevating section 20 is not limited to the configuration installed on the trolley 7. The configuration may be such that the elevating section 20 is installed between the traveling device 3 and the columnar member 5 or in the traveling device 3 itself. It is good also as a structure where the elevating part 20 is installed in the middle part of the columnar member 5 which comprises the leg structure 2, or between the columnar member 5 and the girder 4. The trolley 7 can be tilted together with the girder 4 by the lifting section 20. When the girder 4 is configured to tilt, the trolley 7 can be moved in the transverse direction x even after the tilt is adjusted by the adjustment mechanism 11.

1 Crane 2 Leg structure 3 Traveling device 4 Girder 5 Column member 6 Pneumatic tire 7 Trolley 8 Wire rope 9 Hanging tool 10 Container 11 Adjustment mechanism 12 Gas supply source 13 Communication port 14 Pipe 15 Machine room 16 Discharge valve 17 Supply Valve 18 Control part 19 Running surface 20 Lifting part 21 Crank x Traverse direction y Running direction z Vertical direction P Perpendicular line

Claims (4)

a leg structure having a girder extending in the transverse direction; a plurality of traveling devices installed at the lower end of the leg structure and configured to be movable along a running direction perpendicular to the transverse direction; A crane comprising a trolley configured to be movable in a transverse direction along the girder, and a hanging tool suspended from the trolley by a wire rope,
comprising an adjustment mechanism for controlling the inclination of the trolley with at least one of the transverse direction or the running direction as a central axis;
each said traveling device has a pneumatic tire;
A gate-type crane, wherein the adjustment mechanism includes a gas supply source that supplies gas to the pneumatic tire, and a communication port that communicates the inside and outside of the pneumatic tire to allow gas to enter and exit. . a leg structure having a girder extending in the transverse direction; a plurality of traveling devices installed at the lower end of the leg structure and configured to be movable along a running direction perpendicular to the transverse direction; A crane comprising a trolley configured to be movable in a transverse direction along the girder, and a hanging tool suspended from the trolley by a wire rope,
comprising an adjustment mechanism for controlling the inclination of the trolley with at least one of the transverse direction or the running direction as a central axis;
each said traveling device has a pneumatic tire;
A portal crane characterized in that the adjustment mechanism has a pipe that moves gas from one of the pneumatic tires to the other of the pneumatic tires. a leg structure having a girder extending in the transverse direction; a plurality of traveling devices installed at the lower end of the leg structure and configured to be movable along a running direction perpendicular to the transverse direction; A crane comprising a trolley configured to be movable in a transverse direction along the girder, and a hanging tool suspended from the trolley by a wire rope,
comprising an adjustment mechanism for controlling the inclination of the trolley with at least one of the transverse direction or the running direction as a central axis, the adjustment mechanism having a configuration for aligning the lowered hanging tool;
A portal crane , wherein the adjustment mechanism includes an elevating section that is installed on the trolley and moves at least a portion of the trolley in the vertical direction . a leg structure having a girder extending in the transverse direction; a plurality of traveling devices installed at the lower end of the leg structure and configured to be movable along a running direction perpendicular to the transverse direction; A method for controlling a crane comprising a trolley configured to be movable in a transverse direction along the girder, and a hanging device suspended from the trolley by a wire rope,
The trolley is configured to align the hanging tool suspended from the trolley by adjusting the inclination of the trolley with at least one of the transverse direction or the running direction as a central axis,
A crane characterized in that each of the traveling devices has a pneumatic tire, and the inclination of the trolley is adjusted by deforming the pneumatic tire by adjusting the pressure inside the pneumatic tire. control method.

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