Cable crane, transportation method and construction method

Abstract

To provide a cable crane capable of stopping a hanging tool at a stopping time of a traverse trolley even if a distance from the traverse trolley to the hanging tool changes during the deceleration of the traverse trolley.SOLUTION: A cable crane 20 comprises: a transverse trolley 22 installed on a main rope 21 so as to move along the main rope 21; a winch 23 for driving the transverse trolley 22; a hanging tool 29 suspended from the transverse trolley 22; a first position measuring instrument 31 for measuring a position of the transverse trolley 22; a second position measuring instrument 32 for measuring a position of the hanging tool 29; and a control device 40. The control device 40 maintains the deceleration of the transverse trolley 22 if an oscillation angle of the hanging tool 29 is equal to a target value. The control device 40 decreases the deceleration of the transverse trolley 22 if the oscillation angle of the hanging tool 29 is greater than the target value. The control device 40 increases the deceleration of the transverse trolley 22 if the oscillation angle of the hanging tool 29 is smaller than the target value.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a cable crane, a transportation method, and an installation method. [Background technology]

[0002] Cable cranes that are erected between mountains are used to construct concrete structures such as dam embankments in valleys. A cable crane is equipped with a main rope, a traverse trolley, and a bucket. The main rope is stretched across the mountains, the traverse trolley runs along the main rope, and the bucket is hung from the traverse trolley, into which concrete is loaded.

[0003] When using a cable crane to transport concrete from a mountain to a valley, the traveling trolley slows down and stops above the valley, causing the bucket to swing. After the bucket swing stops, the bucket is lowered from the traveling trolley. The concrete is then dropped from the bucket. This procedure causes the bucket swing to lengthen the concrete pouring cycle, which ultimately lengthens the construction period of concrete structures.

[0004] To solve such problems, the technology described in Patent Document 1 has been proposed. Patent Document 1 discloses a technology in which the bucket sway angle and its sway angular velocity are measured by a measuring device, and the deceleration of the traverse trolley is controlled by a control device based on the sway angle and sway angular velocity so that the bucket sway is offset, taking into account the braking distance of the traverse trolley. According to the technology in Patent Document 1, the bucket sway stops when the traverse trolley stops. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent Publication No. 2022-154200 Summary of the Invention [Problem to be solved by the invention]

[0006] The technology of Patent Document 1 is effective under the condition that the distance from the traverse trolley to the center of gravity of the bucket remains constant while the traverse trolley is decelerating. However, if the distance from the traverse trolley to the center of gravity of the bucket changes while the traverse trolley is decelerating, the technology of Patent Document 1 does not necessarily stop the bucket from swinging when the traverse trolley stops. Therefore, an object of the present invention is to enable the hoisting device, such as a bucket, to be stopped when the traverse trolley stops, even if the distance from the traverse trolley to the hoisting device changes while the traverse trolley is decelerating. [Means for solving the problem]

[0007] According to a first aspect of the present invention for solving the above problems, a cable crane includes a main rope stretched between ridges above a valley between the ridges, a traverse trolley installed on the main rope so as to move along the main rope, a drive device for driving the traverse trolley, a hoisting device suspended from the traverse trolley, a first position measuring device for measuring a position of the traverse trolley, a second position measuring device for measuring a position of the hoisting device, and a control device for controlling the drive device to control the speed of the traverse trolley, and when the control device decelerates the traverse trolley, the control device controls the speed of the traverse trolley measured by the first position measuring device. The control device calculates the sway angle of the hoisting device based on the position measured by the first position measuring device and the position measured by the second position measuring device, and as a result of comparing the calculated sway angle of the hoisting device with a target value, if the sway angle of the hoisting device is equal to the target value, the control device decelerates the traverse trolley to maintain the deceleration of the traverse trolley, if the sway angle of the hoisting device is greater than the target value, the control device decelerates the traverse trolley to reduce the deceleration of the traverse trolley, and if the sway angle of the hoisting device is smaller than the target value, the control device decelerates the traverse trolley to increase the deceleration of the traverse trolley.

[0008] According to a second aspect of the present invention, the control device calculates the target value based on a distance from a position measured by the first position measuring device to a destination.

[0009] According to the third aspect of the present invention, the control device calculates the target value to be smaller as the distance from the position measured by the first position measuring device to the destination becomes smaller.

[0010] According to a fourth aspect of the present invention, the cable crane further includes a lifting winch for raising and lowering the hoisting device, and when the control device decelerates the traverse trolley, the control device operates the lifting winch to lower the hoisting device.

[0011] According to a fifth aspect of the present invention, there is provided a method of transporting a load held by a hoisting device using a cable crane including a main rope stretched between mountains above a valley between the mountains, a traverse trolley installed on the main rope so as to move along the main rope, and a hoisting device suspended from the traverse trolley, the method including measuring positions of the traverse trolley and the hoisting device when decelerating the traverse trolley, and adjusting the speed of the hoisting device based on the measured positions of the traverse trolley and the hoisting device. The sway angle of the hoisting device is calculated, and the calculated sway angle of the hoisting device is compared with a target value. If the sway angle of the hoisting device is equal to the target value, the traverse trolley is decelerated to maintain its deceleration. If the sway angle of the hoisting device is greater than the target value, the traverse trolley is decelerated to reduce its deceleration. If the sway angle of the hoisting device is smaller than the target value, the traverse trolley is decelerated to increase its deceleration. When the traverse trolley is decelerated, the hoisting tool may be lowered by operating a lifting winch.

[0012] According to a sixth aspect of the present invention, there is provided a construction method for constructing a structure in the valley by using the transportation method to transport ready mixed concrete as the suspended load to the valley. Effect of the Invention

[0013] According to the present invention, even if the distance from the traverse trolley to the hoisting device changes while the traverse trolley is decelerating, the hoisting device stops when the traverse trolley stops. [Brief description of the drawings]

[0014] [Figure 1] FIG. 1 is a perspective view of a cable crane at a construction site. [Diagram 2] FIG. 2 is a block diagram of a cable crane. [Diagram 3] FIG. 3 is a side view of the traverse trolley and hoisting equipment of the cable crane. [Figure 4] FIG. 4 is a diagram showing the trajectory of the sling. [Diagram 5] FIG. 5 is a graph showing the change in speed of the traverse trolley. [Figure 6] FIG. 6 is a graph showing the relationship between the distance from the traverse trolley to the destination and the target value, and the relationship between that distance and the swing angle. [Figure 7] FIG. 7 is a graph showing the relationship between the distance from the traverse trolley to the destination and the target value. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] Hereinafter, the embodiments will be described with reference to the drawings. The features and technical effects of the embodiments will be understood from the following detailed description and drawings. However, the scope of the present invention is not limited to the embodiments disclosed below. The drawings are provided for illustrative purposes only, and therefore the scope of the present invention is not limited to the illustrations in the drawings.

[0016] [1. Overview of the construction system] FIG. 1 is a perspective view of the construction system 1. The construction system 1 constructs a structure 99, such as a dam embankment, in a valley 93 between mountains 91 and 92. The construction system 1 transports materials, such as ready mixed concrete, from mountain 91 or mountain 92 to the valley 93 for the construction of the structure 99. The construction system 1 may transport materials that are no longer needed in the valley 93 from the valley 93 to mountain 91 or mountain 92.

[0017] The construction system 1 comprises a concrete supply facility 10 and a cable crane 20.

[0018] The concrete supplying facility 10 is constructed on the hillside of a mountain 92. The concrete supplying facility 10 manufactures ready mixed concrete and supplies the manufactured ready mixed concrete to a cable crane 20. Note that another concrete supplying facility may be constructed on the hillside of the mountain 92 together with the concrete supplying facility 10 or instead of the concrete supplying facility 10.

[0019] Cable crane 20 is erected between peaks 91 and 92. Cable crane 20 receives a supply of ready-mix concrete from concrete supply equipment 10 and transports the ready-mix concrete to valley 93. Cable crane 20 may transport materials other than ready-mix concrete to valley 93. Cable crane 20 may transport materials from peak 92 to valley 93. Cable crane 20 may transport materials that are no longer needed in valley 93 from valley 93 to peak 91 or peak 92. Hereinafter, objects such as ready-mix concrete and materials transported by cable crane 20 are referred to as suspended loads.

[0020] [2. Concrete supply equipment] The concrete supply facility 10 comprises a batcher plant 11, a bunker track 12 and a transport vehicle 13.

[0021] The batcher plant 11 is constructed on the side of a mountain 92. The batcher plant 11 mixes cement, water, and aggregate to produce ready-mix concrete.

[0022] The bunker track 12 is laid along the valley 93 from the batcher plant 11 on the side of the mountain 92.

[0023] . The transport vehicle 13 is, for example, a transfer car or a bucket cart. The transport vehicle 13 can travel on the bunker track 12 along the bunker track 12. The transport vehicle 13 repeatedly performs the following operations. First, the transport vehicle 13 receives a supply of ready-mixed concrete at the batcher plant 11 and loads the ready-mixed concrete. The transport vehicle 13 transports the ready-mixed concrete from the batcher plant 11 along the bunker track 12 to the transfer location P1. Next, the transport vehicle 13 transfers the ready-mixed concrete to a hoisting tool 29 described below at the transfer location P1. Next, the transport vehicle 13 returns to the batcher plant 11 to receive the ready-mixed concrete. The transfer location P1 is located along the bunker track 12 and below the main rope 21 described below. In other words, when looking at the bunker track 12 and the main rope 21 from above, the point where the bunker track 12 and the main rope 21 intersect is the transfer location P1.

[0024] [3. Cable crane] The cable crane 20 will be described in detail with reference to Figures 1 to 3. Figure 2 is a block diagram of a control configuration for the cable crane 20. Figure 3 is a side view of the traverse trolley 22 and the hoisting device 29 of the cable crane 20.

[0025] The cable crane 20 is a one-side movable cable crane among the rail-type. A rail-type cable crane is one in which one or both ends of the main ropes 21 erected between peaks 91 and 92 move along valleys 93. A one-side movable cable crane is one in which one or both ends of the main ropes 21 move along valleys 93. The cable crane 20 may be a two-side movable cable crane among the rail-type, or may be a fixed cable crane instead of a rail-type. A two-side movable cable crane is one in which both ends of the main ropes 21 move along valleys 93. A fixed cable crane is one in which both ends of the main ropes 21 are fixed and do not move.

[0026] The cable crane 20 comprises a main rope 21, a traverse trolley 22, a first winch 23, a first tower 24, a pair of second towers 25, a track rope 26, a running trolley 27, a second winch 28, a hoisting device 29, a lifting winch 30, a first position measuring instrument 31, a second position measuring instrument 32, a control device 40 and a pilot 41.

[0027] The first tower 24 is also called a main rope tower. The first tower 24 is constructed in a standing state on the middle or top of a mountain 91.

[0028] The second tower 25 is also called a cable tower. The second tower 25 is constructed standing on the top or middle of a mountain 92. The installation location of the second tower 25 is higher than the installation locations of the batcher plant 11 and the bunker track 12, and the second tower 25 is installed closer to the top of the mountain 92 than the batcher plant 11 and the bunker track 12. The two second towers 25 are lined up along the valley 93 with a gap between them.

[0029] The rail cable 26 is installed on the peak 92 along the valley 93. More specifically, one end of the rail cable 26 is connected to one of the second towers 25, particularly to the top thereof, and the other end of the rail cable 26 is connected to the other second tower 25, particularly to the top thereof, and the rail cable 26 is suspended between these second towers 25.

[0030] The traveling trolley 27 is supported by the rail 26 and is provided so as to be able to travel on and along the rail 26. The traveling trolley 27 is connected to a traveling traction cable, and the traveling traction cable is wound around a second winch .

[0031] The second winch 28 is installed on the mountain 92. More specifically, the second winch 28 is installed in the machine room 82 on the mountain 92. The second winch 28 pulls the traveling trolley 27 so that the traveling traction cable travels along the rail 26 by applying tension to the traveling traction cable by winding and unwinding the traveling traction cable. The second winch 28 has a drum around which the traveling traction cable is wound, and a motor that drives the drum. Note that the traveling trolley 27 may be a self-propelled type instead of a towing type. The self-propelled type refers to a type in which a motor is provided on the traveling trolley 27 and the traveling trolley 27 travels by the power of the motor.

[0032] The main rope 21 is suspended between the peaks 91 and 92 above the valley 93. More specifically, one end of the main rope 21 is connected to the first tower 24, particularly to its top, at the peak 91, and the other end of the main rope 21 is connected to the traveling trolley 27 at the peak 92, so that the main rope 21 is suspended between the first tower 24 and the traveling trolley 27.

[0033] When the cable crane 20 is of a fixed type, one second tower 25 is constructed standing on the top or middle of the mountain 92, and the main rope 21 is stretched between the first tower 24 and the second tower 25. When the cable crane 20 is of a double-sided movable type, two first towers 24 are constructed standing on the top or middle of the mountain 91, a rail cable is stretched between the two first towers 24, the second traveling trolley runs along the rail cable, and the main rope 21 is stretched between the second traveling trolley and the traveling trolley 27.

[0034] The traverse trolley 22 is supported by the main ropes 21 and is provided so as to be able to run on and along the main ropes 21. The traverse trolley 22 is connected to a traverse traction cable, and the traverse traction cable is wound around a first winch 23.

[0035] The first winch 23 is a driving device installed on the mountain 91. More specifically, the first winch 23 is installed in a machine room 81 on the mountain 91. The first winch 23 pulls the traverse trolley 22 so that the traverse traction cable travels along the main ropes 21 by applying tension to the traverse traction cable by winding and unwinding the traverse traction cable. The first winch 23 has a drum around which the traverse traction cable is wound, and a motor that drives the drum. Note that the traverse trolley 22 may be a self-propelled type instead of a towing type. The self-propelled type refers to a type in which a motor as a driving device is provided on the traverse trolley 22 and the traverse trolley 22 travels by the power of the motor.

[0036] The hoisting tool 29 is suspended from the traverse trolley 22 by a hoisting cable 30a and holds a suspended load. The hoisting tool 29 is connected to a lifting winch 30 via the hoisting cable 30a. The hoisting tool 29 is raised and lowered by the lifting winch 30 winding and unwinding the hoisting cable 30a.

[0037] The lifting device 29 has a block 29a and a bucket 29b. The block 29a has a movable pulley around which a hoisting cable 30a is wound. When the lifting winch 30 pays out the hoisting cable 30a, the block 29a rises, and when the lifting winch 30 takes up the hoisting cable 30a, the block 29a descends. The bucket 29b is suspended from the block 29a. The bucket 29b contains and holds a load, particularly concrete. The bucket 29b has a switch 29c at its bottom that is opened and closed by remote control. When the switch 29c is closed, the load is held in the bucket 29b, and when the switch 29c is opened, the load is dropped from the bucket 29b.

[0038] The lifting winch 30 is installed on the mountain 91, more specifically, in the machine room 81. The lifting winch 30 lifts and lowers the hoisting device 29 by applying tension to the hoisting cable 30a by winding and unwinding the hoisting cable 30a. The lifting winch 30 has a drum around which the hoisting cable 30a is wound, and a motor that drives the drum.

[0039] The first position measuring device 31 is attached to the traversing trolley 22. The first position measuring device 31 measures the three-dimensional position of the traversing trolley 22 according to the positioning method of the Global Navigation Satellite System (GNSS) by receiving satellite waves from multiple satellites. The position measured by the first position measuring device 31 is expressed by a three-dimensional Cartesian coordinate system. For example, the X coordinate in the Cartesian coordinate system is either latitude or longitude converted into distance, the Y coordinate is the other converted into distance, and the Z coordinate is altitude (elevation). The first position measuring device 31 periodically measures the position of the traversing trolley 22 at short intervals, and transfers the measured position to the control device 40 wirelessly or by wire each time it measures.

[0040] The second position measuring device 32 is attached to the sling 29, specifically to the block 29a. Like the first position measuring device 31, the second position measuring device 32 measures the position of the sling 29 periodically at short intervals according to the GNSS positioning method, and transfers the measured position to the control device 40 wirelessly or via cable every time a measurement is made. The coordinate system of the position measured by the second position measuring device 32 is common to the coordinate system of the position measured by the first position measuring device 31.

[0041] The position measuring instruments 31 and 32 are not limited to measuring instruments using the GNSS positioning method. For example, the position measuring instruments 31 and 32 may be tracking optical surveying instruments installed on the mountain 91, the mountain 92, or the valley 93. In this case, the first position measuring instrument 31 measures the three-dimensional position of the traverse trolley 22 by optically aiming at the traverse trolley 22 so as to track the traverse trolley 22, and the second position measuring instrument 32 also measures the three-dimensional position of the sling 29 by optical aiming, similar to the first position measuring instrument 31.

[0042] The control device 40 and the operator 41 are installed in a place that overlooks the entire construction site, that is, the entire valley 93, for example, in a control room on the middle or top of the mountains 91, 92. The control device 40 has a computer and various electric circuits. The control device 40 communicates with the position measuring devices 31, 32 by wire or wirelessly, and obtains the positions of the traverse trolley 22 and the hoisting device 29 measured by the position measuring devices 31, 32.

[0043] The control device 40 is connected by wire or wirelessly to the drive circuits of the winches 23, 28, 30 and the switch 29c, and controls the winches 23, 28, 30 and the switch 29c through the drive circuits. The control device 40 controls the first winch 23, whereby the traverse trolley 22 moves along the main ropes 21, and the speed and acceleration of the traverse trolley 22 are controlled. The control device 40 controls the second winch 28, whereby the end of the main ropes 21 and the traveling trolley 27 move along the rail 26. The control device 40 controls the lifting winch 30, whereby the hoisting device 29 is lifted and lowered. The control device 40 controls the switch 29c, whereby the switch 29c is opened and closed.

[0044] The control of the first winch 23 by the control device 40 may be either open-loop control or closed-loop control. Open-loop control means that the control device 40 controls the rotation speed and rotation acceleration of the first winch 23 without monitoring the rotation speed, rotation acceleration, etc. of the first winch 23. Closed-loop control means that the control device 40 controls the rotation speed and rotation acceleration of the first winch 23 while monitoring the rotation speed and rotation acceleration of the first winch 23 and the position of the traverse trolley 22 using a rotary encoder or the like. The control of the winches 28, 30 by the control device 40 may also be either open-loop control or closed-loop control.

[0045] The controller 41 is used to remotely control the winches 23, 28, 30 and the switchgear 29c. The controller 41 has input devices such as an operating lever, a foot pedal, a handle, a push button, a joystick, and a switch. When an operator operates the controller 41, the controller 41 outputs a signal according to the operation to the control device 40, and the control device 40 controls the winches 23, 28, 30 and the switchgear 29c according to the signal. In this way, the winches 23, 28, 30 and the switchgear 29c are remotely controlled. Normally, the cable crane 10 is automatically operated by the control device 40, and an operator manually operates the cable crane 10 as an auxiliary operation using the controller 41.

[0046] [4. Cable crane operation] The operation of the cable crane 10 associated with the control device 40 controlling the winches 23, 28, 30 and the switch 29c will be described. Additionally, a method of transporting ready mixed concrete as a suspended load using the cable crane 10 will be described. Additionally, a method of constructing a structure 99 using the cable crane 10 will be described.

[0047] (1) Coordination of transshipment locations The control device 40 operates the second winch 28, whereby the traveling trolley 27 moves along the rail 26. As a result, the end of the main rope 21 is displaced along the rail 26, and the position of the transfer site P1 is adjusted along the bunker track 12. The length and tension of the main rope 21 may be appropriately adjusted according to the distance from the traveling trolley 27 to the first tower 24 by winding and unwinding the main rope 21 by the winch during the movement of the traveling trolley 27.

[0048] (2) Moving the sling to the transfer area The control device 40 operates the first winch 23, which causes the traverse trolley 22 to move along the main rope 21 toward the mountain 91 and the traveling trolley 27. At the same time, the control device 40 operates the lifting winch 30, which causes the hoisting gear 29 to descend. Then, when the traverse trolley 22 has moved to above the transfer location P1, the control device 40 stops the first winch 23. Furthermore, when the hoisting gear 29 has descended to the transfer location P1, the control device 40 stops the lifting winch 30. The timing at which the control device 40 stops the lifting winch 30 may be the same as the timing at which the control device 40 stops the first winch 23.

[0049] At this time, the transport vehicle 13 transports the ready-mixed concrete from the batcher plant 11 to the transfer location P1.

[0050] (3) Transshipment The control device 40 controls the switch 29c, whereby the switch 29c is closed. Then, the transport vehicle 13 performs a transfer operation, whereby the ready-mixed concrete is transferred from the transport vehicle 13 to the bucket 29b of the hoisting tool 29.

[0051] (4) Transportation of ready-mix concrete to the destination 4 is a diagram showing the trajectory of the hoisting tool 29 when the hoisting tool 29 moves from the transfer location P1 to the destination P2. In FIG. 4, the trajectory of the hoisting tool 29 is indicated by a circle.

[0052] The destination P2 refers to the destination to which the ready-mix concrete is transported. The point P3 where the main rope 21 intersects with the transfer location P1 in a vertically upward direction is called the departure point P3. The point P4 where the main rope 21 intersects with the transfer location P2 in a vertically upward direction is called the destination P4. The positions of the transfer location P1, the destination P2, the departure point P3, and the destination P4 in the three-dimensional orthogonal coordinate system are known data determined from the design data of the structure 99, etc. In other words, the control device 40 stores in advance the XYZ coordinates of the transfer location P1, the destination P2, the departure point P3, and the destination P4.

[0053] After the ready-mixed concrete is transferred, the control device 40 accelerates the first winch 23 so as to gradually increase the rotation speed of the first winch 23, and the traverse trolley 22 moves from the departure point P3 toward the destination P4 while accelerating. The acceleration of the traverse trolley 22 during the acceleration of the traverse trolley 22 may be constant or may gradually increase over time. The control device 40 may also calculate the swing angle θ [rad] and its angular velocity ω [rad / s] of the hoisting tool 29 based on the measured position of the traverse trolley 22 and the measured position of the hoisting tool 29 measured by the position measuring devices 31 and 32, and adjust the speed and acceleration of the first winch 23 based on the swing angle θ and the angular velocity ω. The adjusted speed and acceleration of the first winch 23 contribute to offsetting the swing of the hoisting tool 29. 3, the shake angle θ is an angle formed by a vertical line passing through the position detection unit 31 and a line passing through the position detection unit 31 and the position detection unit 32. The angular velocity ω is calculated by differentiating the shake angle θ with respect to time. At the same time that the traverse trolley 22 starts to move, the control device 40 operates the lifting winch 30, thereby lifting the hoisting tool 29.

[0054] When the hoisting tool 29 rises close to the traverse trolley 22, the control device 40 stops the lifting winch 30. Also, when the speed of the first winch 23 rises to a first predetermined value, the control device 40 controls the first winch 23 at a constant speed so as to maintain the rotation speed of the first winch 23 at the first predetermined value. Therefore, the traverse trolley 22 moves at a constant speed V1 [m / s]. During the constant speed movement of the traverse trolley 22, the hoisting tool 29 is suspended almost vertically from the traverse trolley 22. Note that, since the acceleration of the first winch 23 and the traverse trolley 22 was controlled by the control device 40 based on the swing angle θ and the angular velocity ω during the acceleration before the constant speed movement of the traverse trolley 22, the swing of the hoisting tool 29 stops when the movement of the traverse trolley 22 switches from the accelerating movement to the constant speed movement.

[0055] While the traverse trolley 22 is moving at a constant speed, the control device 40 operates the lifting winch 30, thereby lowering the hoisting device 29.

[0056] During the constant speed movement of the traverse trolley 22, the control device 40 monitors the distance from the traverse trolley 22 to the destination P4. Specifically, every time the control device 40 obtains the measured position of the traverse trolley 22 measured by the first position measuring device 31 from the first position measuring device 31, it calculates the distance from the traverse trolley 22 to the destination P4 based on the measured position of the traverse trolley 22 and the position of the destination P4, and compares the distance with a threshold. Here, the threshold is not a fixed value but a positive value determined from the rotation speed of the first winch 23, i.e., the speed of the traverse trolley 22, and the control device 40 calculates the threshold from the speed of the traverse trolley 22. In other words, the equation for calculating the threshold is a function of the speed of the traverse trolley 22, and for example, the higher the speed of the traverse trolley 22, the higher the threshold calculated by the control device 40. Th [m] shown in FIG. 4 is the value of the threshold.

[0057] If the comparison result shows that the distance from the traverse trolley 22 to the destination P4 does not reach the threshold value Th, the control device 40 continues the constant speed control of the first winch 23. If the distance from the traverse trolley 22 to the destination P4 reaches the threshold value Th as a result of the comparison, the control device 40 starts deceleration control of the first winch 23. The deceleration control will be described in detail below with reference to Figs. 5 to 7. Fig. 5 is a graph showing the change in the speed V [m / s] of the traverse trolley 22. In Fig. 5, the horizontal axis represents the distance L [m] from the traverse trolley 22 to the destination P4, and the vertical axis represents the speed V of the traverse trolley 22. Fig. 6 is a graph showing the relationship between the distance L from the traverse trolley 22 to the destination P4 and the target value C [rad], and the relationship between the distance L and the swing angle θ [rad]. Fig. 7 is a graph showing the relationship between the distance L from the traverse trolley 22 to the destination P4 and the target value C [rad]. In Figs. 6 and 7, the horizontal axis represents the distance L [m] from the traverse trolley 22 to the destination P4, and the vertical axis represents the target value C and the swing angle θ.

[0058] When the distance from the traverse trolley 22 to the destination P4 reaches the threshold value Th, the control device 40 reduces the rotation speed of the first winch 23 from a first predetermined value to a second predetermined value. As a result, the speed V of the traverse trolley 22 suddenly drops from speed V1 [m / s] to speed V2 [m / s], and the hoisting tool 29 and ready-mixed concrete perform a pendulum motion with the traverse trolley 22 as the fulcrum. Here, if the hoisting tool 29 suspended from the traverse trolley 22 moving in translation and the ready-mixed concrete are considered as a rigid pendulum, the equation of motion of the system consisting of the traverse trolley 22 and the rigid pendulum is expressed as follows:

[0059]

number

[0060] Since this equation of motion describes the relationship between the acceleration of the traverse trolley 22 and the swing angle of the rigid pendulum, it can be seen that the swing angle of the rigid pendulum can be controlled by controlling the speed and acceleration of the traverse trolley 22. In order to control the swing angle of the rigid pendulum, i.e., the suspending device 29, the control device 40 performs the following processing.

[0061] After the distance from the traverse trolley 22 to the destination P4 reaches the threshold value, the control device 40 performs the following sway angle calculation process, target value calculation process, comparison process, and deceleration adjustment process each time it obtains the measured position of the traverse trolley 22 and the measured position of the hoisting device 29 from the position measuring devices 31, 32.

[0062] In the sway angle calculation process, the control device 40 calculates the sway angle θ [rad] of the suspending device 29 based on the measured positions of the traverse trolley 22 and the suspending device 29 measured by the position measuring devices 31, 32. Furthermore, the control device 40 calculates the angular velocity ω by differentiating the sway angle θ of the suspending device 29 with respect to time.

[0063] In the target value calculation process, the control device 40 calculates the target value C [rad] based on the measured position of the traverse trolley 22. More specifically, the control device 40 calculates the distance from the traverse trolley 22 to the destination P4 based on the measured position of the traverse trolley 22 and the position of the destination P4, and then calculates the target value C from the distance. As shown in FIG. 6 or FIG. 7, the target value C is a positive value determined from the distance from the traverse trolley 22 to the destination P4. In other words, the equation for calculating the target value C is a function of the distance from the traverse trolley 22 to the destination P4, and the shorter the distance, the lower the target value C calculated by the control device 40 becomes. In the example shown in FIG. 6, the control device 40 calculates the target value C corresponding to the distance from the traverse trolley 22 to the destination P4 from the equation of a linear function determined by a positive proportionality constant. In the example shown in Figure 7, the control device 40 calculates a target value C corresponding to the distance from the traversing trolley 22 to the destination P4 from the equation of a function that draws a downward convex curve passing through the origin on a graph defined by the vertical and horizontal axes.

[0064] In the comparison process, the control device 40 compares the swing angle θ calculated in the swing angle calculation process with the target value C calculated in the target value calculation process.

[0065] In the deceleration adjustment process, the control device 40 adjusts the deceleration of the first winch 23 according to the comparison result of the comparison process. The deceleration refers to the absolute value of the negative acceleration. Therefore, the greater the deceleration, the greater the amount of speed reduction per unit time.

[0066] The deceleration adjustment process will now be described in detail. If the sway angle θ is equal to the target value C, the control device 40 reduces the rotational speed of the first winch 23 so as to maintain the deceleration of the first winch 23, so that the traverse trolley 22 translates with a uniform deceleration.

[0067] If the sway angle θ is larger than the target value C, the control device 40 reduces the rotation speed of the first winch 23 so as to reduce the deceleration of the first winch 23, thereby reducing the deceleration of the traverse trolley 22. As a result, the hoisting device 29 swings so that its sway angle approaches the target value C. Note that the greater the absolute value of the difference between the sway angle θ and the target value C, the greater the amount of reduction in the deceleration of the first winch 23 that the control device 40 reduces may be.

[0068] If the sway angle θ is smaller than the target value C, the control device 40 reduces the rotation speed of the first winch 23 so as to increase the deceleration of the first winch 23, and therefore the deceleration of the traverse trolley 22 increases. Therefore, the hoisting device 29 swings so that its sway angle approaches the target value C. Note that the greater the absolute value of the difference between the sway angle θ and the target value C, the greater the increase in the deceleration of the first winch 23 that the control device 40 increases may be.

[0069] Thereafter, until the traverse trolley 22 reaches the destination P4, the control device 40 performs the swing angle calculation process, the target value calculation process, the comparison process, and the deceleration adjustment process every time it acquires a measured position from the position measuring devices 31, 32.

[0070] In addition, from the time when the distance from the traverse trolley 22 to the destination P4 reaches the threshold value Th until the swing angle θ reaches the target value C as shown at the intersection point P in Fig. 6, the control device 40 may simply gradually decrease the speed of the traverse trolley 22 without performing the deceleration adjustment process, or may maintain the speed of the traverse trolley 22 at the speed V2 [m / s]. Also, from the time when the distance from the traverse trolley 22 to the destination P4 reaches the threshold value Th until the angular velocity ω becomes zero, the control device 40 may simply gradually decrease the speed of the traverse trolley 22 without performing the deceleration adjustment process, or may maintain the speed of the traverse trolley 22 at the speed V2 [m / s].

[0071] When the traverse trolley 22 reaches the destination P4, the rotation speed of the first winch 23 becomes zero by the control device 40 as described above. Therefore, the traverse trolley 22 stops at the destination P4. In addition, since the control device 40 adjusts the deceleration of the first winch 23 and therefore the deceleration of the traverse trolley 22 by the deceleration adjustment process, the swing of the hoisting gear 29 also stops when the traverse trolley 22 reaches the destination P4. In particular, if the equation for determining the target value C is a curved function as shown in FIG. 7, the time when the swing of the hoisting gear 29 stops easily coincides with the time when the traverse trolley 22 reaches the destination P4.

[0072] As described above, even when the control device 40 is performing deceleration control, the hoisting tool 29 continues to descend. When the traverse trolley 22 reaches the destination P4 or shortly before that, the hoisting tool 29 reaches the height of the transport destination P2, so the control device 40 stops the lifting winch 30. Therefore, when the traverse trolley 22 reaches the destination P4, the hoisting tool 29 also reaches the destination P2.

[0073] (5) Drop Thereafter, the control device 40 controls the switch 29c to open the switch 29c. Therefore, the ready-mix concrete in the bucket 29b is dropped from the bucket 29b to the area below. The switch 29c may be opened by an operator operating the control device 41.

[0074] (6) Return of the sling to the transfer area After the ready-mix concrete has been dropped, the control device 40 accelerates the first winch 23 by controlling the first winch 23 so as to gradually increase its rotation speed, whereby the traverse trolley 22 moves from the destination P4 towards the starting point P3 while accelerating. The acceleration of the traverse trolley 22 during the acceleration of the traverse trolley 22 may be constant or may gradually increase over time.

[0075] At the same time that the traverse trolley 22 starts to move, the control device 40 operates the lifting winch 30, thereby lifting the hoisting tool 29.

[0076] When the hoisting device 29 rises close to the traverse trolley 22, the control device 40 stops the lifting winch 30. Furthermore, when the speed of the first winch 23 rises to a first predetermined value, the control device 40 controls the first winch 23 at a constant speed so as to maintain the rotational speed of the first winch 23 at the first predetermined value.

[0077] When the traverse trolley 22 approaches the starting point P3, the control device 40 controls the first winch 23 to decelerate so that the rotation speed of the first winch 23 gradually decreases. Therefore, the traverse trolley 22 moves toward the starting point P3 while decelerating. In addition, the control device 40 operates the lifting winch 30, so that the hoisting tool 29 descends.

[0078] When the traverse trolley 22 reaches the departure point P3, the control device 40 stops the first winch 23. When the traverse trolley 22 reaches the departure point P3 or shortly before, the hoisting tool 29 reaches the height of the transfer location P1, so the control device 40 stops the lifting winch 30. Therefore, when the traverse trolley 22 reaches the departure point P3, the hoisting tool 29 also reaches the transfer location P1.

[0079] Thereafter, the above-mentioned processes of “(3) transfer,” “(4) transportation of the ready-mixed concrete to the destination,” “(5) dropping,” and “(6) returning the hoisting equipment to the transfer location” are repeated, so that the ready-mixed concrete is successively transported to valley 93 and dropped.

[0080] 5. Beneficial Effects When the traverse trolley 22 moves to the destination P4, if the distance from the traverse trolley 22 to the destination P4 becomes equal to or less than the threshold value Th, the traverse trolley 22 is decelerated and the deceleration of the traverse trolley 22 is adjusted. Specifically, if the measured swing angle θ of the hoisting tool 29 is equal to the target value C, the deceleration of the traverse trolley 22 is maintained, if the swing angle θ is greater than the target value C, the deceleration of the traverse trolley 22 is decreased, and if the swing angle θ is smaller than the target value C, the deceleration of the traverse trolley 22 is increased. Therefore, even if the hoisting tool 29 descends during the deceleration of the traverse trolley 22 and the distance from the center of gravity of the hoisting tool 29 and the load to the traverse trolley 22 changes, the swing angle θ of the hoisting tool 29 converges to the target value C. Therefore, when the traverse trolley 22 reaches the destination P4, the swing of the hoisting tool 29 also stops.

[0081] 6 and 7, the formula for calculating the target value C is a function of the distance from the traverse trolley 22 to the destination P4, and the closer the traverse trolley 22 is to the destination P4, the lower the calculated target value C. The deceleration of the traverse trolley 22 is adjusted according to the comparison result between the target value C and the swing angle θ, so that when the traverse trolley 22 reaches the destination P4, the swing of the hoisting device 29 also stops.

[0082] When the traverse trolley 22 moves to the destination P4, the hoisting tool 29 descends, and when the traverse trolley 22 reaches the destination P4, the swinging of the hoisting tool 29 stops. Therefore, immediately after the traverse trolley 22 reaches the destination P4, ready-mix concrete can be dropped from the bucket 29b below it. The concrete pouring cycle per one time is short, and the construction period of the structure 99 can be shortened. [Explanation of symbols]

[0083] 20 Cable Crane 21 Main rope 22 Traverse trolley 23 No. 1 winch (drive unit) 29 Lifting equipment 31 First Position Measuring Instrument 32 Second position measuring instrument 40 Control device

Claims

1. A main rope is stretched between the peaks above a valley between the peaks; A traverse trolley mounted on the main rope so as to move along the main rope; A drive device that drives the traverse trolley; A hanging tool suspended from the traverse trolley; a first position measuring device for measuring a position of the traverse trolley; a second position measuring device that measures the position of the hanging device; a control device for controlling the drive device to thereby control the speed of the traverse trolley; A lifting winch that lifts and lowers the hoisting tool, When the control device decelerates the traverse trolley, The control device operates the lifting winch to lower the hoisting tool, the control device calculates a swing angle of the suspending device based on the position measured by the first position measuring device and the position measured by the second position measuring device; The control device compares the calculated swing angle of the sling tool with a target value, and if the swing angle of the sling tool is equal to the target value, the control device decelerates the traverse trolley so as to maintain the deceleration of the traverse trolley; If the swing angle of the hoist is greater than the target value, the control device decelerates the traverse trolley so as to reduce the deceleration of the traverse trolley; If the swing angle of the hoist is smaller than the target value, the control device decelerates the traverse trolley so as to increase the deceleration of the traverse trolley. Cable crane.

2. The control device calculates the target value based on a distance from the position measured by the first position measuring device to a destination. The cable crane according to claim 1.

3. The control device calculates the target value to be smaller as the distance from the position measured by the first position measuring device to the destination becomes smaller. A cable crane as claimed in claim 2.

4. A main rope is stretched between the peaks above a valley between the peaks; A traverse trolley mounted on the main rope so as to move along the main rope; A hanging tool suspended from the traverse trolley; a lifting winch that lifts and lowers the hoisting tool, and a transport method for transporting a load held by the hoisting tool using a cable crane including the lifting winch, When the traverse trolley is decelerated, The lifting winch is operated to lower the lifting tool, Measure the positions of the traverse trolley and the hoisting tool; Calculating a swing angle of the hoisting tool based on the measured positions of the traverse trolley and the hoisting tool; As a result of comparing the calculated swing angle of the hoisting tool with a target value, if the swing angle of the hoisting tool is equal to the target value, the traverse trolley is decelerated to maintain the deceleration of the traverse trolley, if the swing angle of the hoisting tool is greater than the target value, the traverse trolley is decelerated to reduce the deceleration of the traverse trolley, and if the swing angle of the hoisting tool is smaller than the target value, the traverse trolley is decelerated to increase the deceleration of the traverse trolley. Transportation method.

5. A construction method for constructing a structure in the valley by transporting ready mixed concrete as the suspended load to the valley using the transportation method according to claim 4.

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