Unloading method and crane hook

Abstract

To provide an unloading method capable of opening an opening of a hook body by rotating a stopper by crane operation.SOLUTION: An unloading method for removing a suspended load from a crane hook including a hook main body having a hook portion, and a stopper rotatably provided on the hook main body and configured to switch between a closed state in which an opening of the hook portion is closed by rotation and an open state in which the opening is opened, the method including connecting a structure different from the crane hook and the stopper by a connection member, and rotating the stopper by lowering the crane hook to switch from the closed state to the open state.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a crane hook and a method for lowering a load, in which a stopper is rotated by lowering the crane hook to remove a suspended load. [Background technology]

[0002] When transporting a heavy load using an overhead crane, a sling fixed to the heavy load is hooked onto the crane hook and lifted for transport. For safety reasons, this crane hook is provided with a stopper that prevents the sling hook from escaping from the hook portion of the hook body. The stopper is usually rotatably mounted on the top of the hook body, and by rotating the stopper, it switches between a closed state in which the hook portion opening is closed and an open state in which the hook portion opening is open. In other words, when the hook portion opening is closed by the stopper, the heavy load is lifted by the hook body and transported to a predetermined location by the overhead crane. After transporting the load to the predetermined location, the stopper is rotated to open the hook portion opening and remove the load from the hook body.

[0003] With such a crane hook, when removing a suspended load, as described above, an operator rotates the stopper to the open state, and then, while maintaining the open state, another operator operates the overhead crane to remove the suspended load from the hook body. As such, the work of removing a suspended load from a crane hook requires two operators, which poses problems in terms of work efficiency and safety.

[0004] To address this problem, Patent Document 1 discloses a hook for lifting workpieces, in which a rope connected to a stopper and a rope connected to the hook body are passed through an upper ring, and an operator can pull the other ends of the ropes. According to Patent Document 1, the stopper is opened by pulling the other end of the rope connected to the stopper, and the hook body is rotated half a turn by further pulling the other end of the rope connected to the hook body. This allows a single operator to remove a load from the hook body. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Utility Model Registration No. 3115571 Summary of the Invention [Problem to be solved by the invention]

[0006] In the workpiece lifting hook disclosed in Patent Document 1, an operator must pull the other end of the rope connected to the stopper to rotate the stopper. Since the stopper is generally biased so that it cannot be easily released, the operating force required to rotate the stopper can be large. In such cases, the operator must pull the rope with a large force, which increases the burden on the operator.

[0007] The present invention was made in consideration of the problems of the prior art, and its object is to provide a method for unloading cargo that allows a stopper to be rotated by crane operation to open the opening of the hook body. Another object of the present invention is to provide a crane hook that allows a stopper to be rotated by crane operation to open the opening of the hook body. [Means for solving the problem]

[0008] The means for solving the above problems are as follows. [1] A method for removing a suspended load from a crane hook having a hook body with a hook portion and a stopper that is rotatably mounted on the hook body and that rotates to switch between a closed state that closes the opening of the hook portion and an open state that opens the opening, wherein the method connects a structure other than the crane hook to the stopper with a connecting member, and rotates the stopper by lowering the crane hook to switch from the closed state to the open state. [2] A method of unloading described in [1], in which the crane hook is moved while remaining in the open state, and the load is removed from the crane hook. [3] A method of unloading described in [1] or [2], in which when the crane hook is lowered, a structure other than the crane hook is connected to the stopper with a connecting member. [4] A crane hook to be attached to a crane, comprising: a hook body having a support portion provided at an upper portion and a hook portion; a stopper rotatably provided on the support portion and closing the opening of the hook portion; and a connecting member that pulls the stopper to rotate the stopper, wherein the stopper has a bearing portion that fits into the support portion, a stopper portion that rotates to switch between a closed state that closes the opening of the hook portion and an open state that opens the opening, and a fixing portion provided at a position spaced from the bearing portion, and the connecting member connects the fixing portion to a structure different from the crane hook. [Effects of the Invention]

[0009] In the unloading method of the present invention, the crane hook is lowered by operating the crane to rotate the stopper, thereby opening the opening of the hook body. Therefore, there is no need to pull the rope connected to the stopper to rotate it in order to open the hook body, which reduces the burden on the worker compared to conventional unloading methods. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 1 is a schematic diagram of a crane hook. [Figure 2] FIG. 2 is a schematic diagram showing a state in which a workpiece as a load is being lifted by a crane hook in a closed state. [Figure 3] FIG. 3 is a schematic diagram showing the crane hook when it is lowered and the opening is in an open state. [Figure 4] FIG. 4 is a schematic diagram showing a state in which the crane hook has been moved to the left and the workpiece has been removed from the crane hook. DETAILED DESCRIPTION OF THE INVENTION

[0011] The present invention will be described in detail below through embodiments of the present invention. The following embodiments are preferred examples of the present invention, and the present invention is not limited to these embodiments. FIG. 1 is a schematic diagram of a crane hook 10 to which the unloading method according to this embodiment can be applied. FIG. 1(a) is a schematic diagram of the crane hook 10 in a closed state in which the opening 26 is closed, and FIG. 1(b) is a schematic diagram of the crane hook 10 in an open state in which the opening 26 is open.

[0012] The crane hook 10 is attached to a connecting portion 60 that is connected to a crane wire 62 of a crane (not shown) and is used to lift a load. The crane hook 10 has a hook body 20, a stopper 30, and a connecting member 40.

[0013] The hook body 20 is a J-shaped iron member having a pivot support portion 22 provided at the top and a hook portion 24. The pivot support portion 22 is a cylindrical protrusion that protrudes from the front and back surfaces of the hook body 20. A load can be attached to and removed from the hook body 20 through an opening 26 formed by the hook portion 24.

[0014] The stopper 30 is rotatably attached to the pivot support portion 22 of the hook body 20. The stopper 30 is made of iron and may be configured, for example, by two L-shaped members joined together by a joining member. The distance between the two L-shaped members is slightly wider than the thickness of the hook body 20, and the stopper 30 is attached so that the hook body 20 is sandwiched between the two L-shaped members.

[0015] The stopper 30 has a bearing portion 32, a removal prevention portion 34, and a fixing portion 36. The bearing portion 32 is provided on two L-shaped members and is a hole that fits onto the pivot portion 22 of the hook body 20. The removal prevention portion 34 is provided in a position that closes the opening 26 formed by the hook portion 24. When the stopper 30 rotates around the bearing portion 32, the removal prevention portion 34 also rotates. When the stopper 30 rotates, it switches between a closed state ( FIG. 1( a) ) in which the opening 26 is closed by the removal prevention portion 34, and an open state ( FIG. 1( b) ) in which the opening 26 is opened by the removal prevention portion 34.

[0016] The fixed portion 36 is provided at a position spaced apart from the bearing portion 32. A connecting member 40 is connected to the fixed portion 36. The connecting member 40 connects the fixed portion 36 to a structure 50 that is different from the crane hook 10. The structure 50 is an accessory facility of the crane and moves together with the crane.

[0017] The connecting member 40 is, for example, a torque reel. A torque reel 42 that generates a tractive force greater than the rotational force of the stopper 30 is fixed to the structure 50, and a torque reel wire 44 is connected to the fixing portion 36. As a result, when the crane hook 10 descends, the torque reel wire 44 pulls the stopper 30, allowing the stopper 30 to rotate. Furthermore, after the stopper 30 reaches its rotation limit, the torque reel wire 44 is pulled out from the torque reel 42, so the connecting member 40 does not hinder the descent of the crane hook 10.

[0018] In this way, in the crane hook 10 according to this embodiment, the fixing portion 36 of the stopper 30 and the structure 50 are connected by the connecting member 40. Therefore, when the crane hook 10 is lowered, the stopper 30 is pulled by the connecting member 40, causing the stopper 30 to rotate. This switches the state of FIG. 1(a) in which the opening 26 is closed by the anti-detachment portion 34 (closed state) to the state of FIG. 1(b) in which the opening 26 is open (open state).

[0019] The position of the fixing portion 36 to which the connecting member 40 is fixed is important in order to rotate the stopper 30 by the lowering of the crane hook 10. To rotate the stopper 30 by the lowering of the crane hook 10, it is preferable to provide the fixing portion 36 at a position separated from the bearing portion 32.

[0020] By providing the fixing part 36 in this position, the lowering of the crane hook 10 causes the connecting member to pull the stopper 30, thereby rotating the stopper 30. As a result, by lowering the crane hook 10 through crane operation, the stopper 30 can be rotated, and the opening 26 can be switched from a closed state in which the opening 26 is closed by the anti-detachment part 34 to an open state in which the opening 26 is open. As a result, the crane hook 10 can be switched to an open state in which the opening 26 of the hook body 20 is open, without pulling the rope to rotate the stopper 30, and this provides a crane hook that can reduce the burden on the worker compared to conventional crane hooks.

[0021] Next, we will explain how to transport, lower, and remove a suspended load using the crane hook 10. Figure 2 is a schematic diagram showing a state in which the crane hook 10 in a closed state is lifting a workpiece 70 as a suspended load.

[0022] As shown in Figure 2, when workpiece 70 is being lifted, crane hook 10 is maintained in a closed state with opening 26 closed. In this state, workpiece 70 is transported to the target position by the crane. Note that since structure 50 moves together with the crane, the distance between fixing portion 36 and structure 50 does not change, and stopper 30 does not rotate.

[0023] 3 is a schematic diagram showing the crane hook 10 after it has been lowered and the opening 26 is in an open state. Once the workpiece 70 has been transported to the target position, it is removed from the crane hook 10. In this case, the crane hook 10 is first lowered by operating the crane. As a result, the workpiece 70 is suspended and lands at the target position. Furthermore, as the crane hook 10 is lowered, the stopper 30 is pulled by the connecting member 40 and rotates, and the crane hook 10 is switched to an open state in which the opening 26 is open.

[0024] 4 is a schematic diagram showing the state in which the crane hook 10 has been moved to the left and the workpiece 70 has been removed from the crane hook 10. Because the workpiece 70 has landed due to the descent of the crane hook 10, the engaging portion 72 of the workpiece 70 is separated from the hook body 20. Furthermore, since the crane hook 10 is in an open state with the opening 26 open, the workpiece 70 can be easily removed from the crane hook 10 by operating the crane to move the crane hook 10 to the left while it remains in this open state. In this way, with the unloading method according to this embodiment, the workpiece 70 that has been engaged and lifted by the crane hook 10 can be removed from the crane hook 10 at a predetermined position and unloaded.

[0025] Furthermore, when the crane hook 10 is moved to the left, the pulling of the stopper 30 by the connecting member 40 is released. Therefore, after the crane hook 10 is moved to the left and the workpiece 70 is removed from the crane hook 10, the opening 26 of the hook body 20 is switched back to the closed state.

[0026] Note that the crane hook 10 may have a biasing member that biases the stopper 30 in the rotation direction to close the opening 26, so that the opening 26 is maintained in a closed state in which it is closed by the anti-detachment portion 34 when the pulling by the connecting member 40 is released. This prevents the stopper 30 from rotating while the workpiece 70 is being lifted, and prevents the opening 26 from accidentally switching to an open state.

[0027] As described above, the crane hook 10 according to this embodiment can be switched to an open state in which the opening 26 of the hook body 20 is opened by lowering the crane hook 10 through crane operation, thereby rotating the stopper 30. This allows the operator to switch to the open state without pulling the rope to rotate the stopper 30, resulting in a crane hook that can reduce the burden on the operator compared to conventional crane hooks.

[0028] In this embodiment, the torque reel 42 and the torque reel wire 44 are respectively connected to the structure 50 and the fixed part 36, which are ancillary equipment of the crane, but this is not limited to this. The torque reel 42 may be fixed at the fixed part 36, and when the crane hook 10 is lowered, the torque reel wire 44 may be pulled out from the torque reel 42 and connected to a structure near the target position. This makes it possible to apply the unloading method and crane hook 10 according to this embodiment to structures that are not ancillary equipment of the crane and do not move with the crane.

[0029] Alternatively, the torque reel 42 may be fixed to a structure near the target position, and when the crane hook 10 is lowered, the torque reel wire 44 may be pulled out from the torque reel 42 and connected to the fixed part 36. When connecting the torque reel wire 44 to the fixed part 36, the worker may use a hand hook to pull out the torque reel wire 44 and connect the torque reel wire 44 to the fixed part 36. This makes it possible to apply the unloading method and crane hook 10 according to this embodiment to structures that are not ancillary equipment of a crane and do not move with the crane. [Explanation of symbols]

[0030] 10 Crane Hook 20 Hook body 22 axis branches 24 Hook part 26 Aperture 30 Stopper 32 Bearing section 34 Stopper 36 Fixed part 40 Connecting member 42 Torque reel 44 Torque reel wire 50 Structures 60 Connection part 62 Crane Wire 70 Work 72 Locking part

Claims

1. a hook body having a hook portion; a stopper that is rotatably provided on the hook body and that rotates to switch between a closed state in which the opening of the hook portion is closed and an open state in which the opening is opened; A method for removing a suspended load from a crane hook, comprising: A method of unloading a cargo, comprising connecting a structure different from the crane hook to the stopper with a connecting member, and lowering the crane hook to rotate the stopper and switch it from the closed state to the open state.

2. The unloading method according to claim 1 , further comprising the steps of: moving the crane hook while keeping the crane hook in the open state; and removing the suspended load from the crane hook.

3. 3. The unloading method according to claim 1, wherein when the crane hook is lowered, a structure different from the crane hook is connected to the stopper by a connecting member.

4. A crane hook attached to a crane, a hook body having a pivot support portion provided at an upper portion and a hook portion; a stopper rotatably provided on the pivot support portion and configured to close the opening of the hook portion; a connecting member that pulls the stopper to rotate the stopper; and the stopper has a bearing portion that fits into the pivot support portion, a stopper portion that rotates to switch between a closed state that closes the opening of the hook portion and an open state that opens the opening, and a fixing portion that is provided at a position separated from the bearing portion, The connecting member connects the fixed portion to a structure different from the crane hook.

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