Weights for overwinding detection devices, overwinding detection devices, and construction machinery

Abstract

To provide a weight for an overwinding detection device, an overwinding detection device, and construction machinery that can be easily attached and detached by an operator. [Solution] The weight comprises a weight body having an annular peripheral wall and a biasing unit incorporated into the weight body, wherein the weight body has a first weight piece forming a part of the peripheral wall and a second weight piece forming at least a part of the remainder of the peripheral wall, the first weight piece and the second weight piece have edges that can approach or separate from each other, and when the edges of the first weight piece and the second weight piece are separated from each other in an open state, a gap is formed in the peripheral wall for inserting and removing a wire rope, and the biasing unit is configured to bias the first weight piece and the second weight piece so that the edges of the first weight piece and the second weight piece are in contact with each other in a closed state.

Description

Technical Field

[0001] The present invention relates to a weight for an overwind detection device, an overwind detection device, and a construction machine.

Background Art

[0002] Conventionally, in a crane or the like, an overwind detection device for detecting overwind of a hook due to winding up of a wire rope suspended from a boom is known (for example, Patent Document 1). The overwind detection device described in Patent Document 1 includes an annular weight suspended from a boom by a weight suspension rope and passed through the wire rope.

[0003] The weight described in Patent Document 1 is composed of an assembly of a U-shaped weight body having a side opening and a block member fixedly connected to the weight body by bolts so as to close the side opening of the weight body. Further, the weight described in Patent Document 1 is formed in an annular shape by the weight body and the block member, and has a rope passing hole through which a wire rope passes at the center.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] In the overwind detection device described in Patent Document 1, in order to attach and detach the weight to and from the wire rope in a state where a hook is attached to the wire rope, it is necessary to attach and detach the bolts and the block member each time, and there is a problem that the work is complicated. Further, in the overwind detection device described in Patent Document 1, there is also a problem that there is a risk of losing the bolts and the block member during attachment and detachment or storage of the weight.

[0006] This invention has been made in view of these problems, and aims to provide a weight for an overwinding detection device, an overwinding detection device, and construction machinery that can be easily attached and detached by an operator. [Means for solving the problem]

[0007] The weight for an overwinding detection device according to the present invention comprises a weight body having an annular peripheral wall portion and a biasing portion incorporated into the weight body, wherein the weight body has a first weight piece that forms a part of the peripheral wall portion and a second weight piece that forms at least a part of the remainder of the peripheral wall portion, the first weight piece and the second weight piece have edges that can approach or separate from each other, and when the edges of the first weight piece and the second weight piece are separated from each other in an open state, a gap is formed in the peripheral wall portion for inserting and removing the wire rope, and the biasing portion is configured to bias the first weight piece and the second weight piece so that the edges of the first weight piece and the second weight piece are in contact with each other in a closed state.

[0008] In the weight for an overwinding detection device according to the present invention, the weight body may have an operating section for performing an operation to transition from the closed state to the open state.

[0009] In the weight for an overwinding detection device according to the present invention, the upper end of the edge portion and the lower end of the edge portion may be at different positions in the circumferential direction of the peripheral wall portion.

[0010] In the weight for an overwinding detection device according to the present invention, the first weight piece and the second weight piece may have shapes that are inverted vertically along the axial direction of the peripheral wall portion.

[0011] The overwinding detection device according to the present invention is characterized by comprising the above-described overwinding detection device weight and a detector that outputs a detection signal indicating overwinding of a hook suspended below the overwinding detection device weight via the wire rope when the overwinding detection device weight is lifted against the weight of the overwinding detection device.

[0012] The construction machine according to the present invention is characterized by comprising the above-described overwinding detection device, at least one of a boom and a jib, a construction machine body having a wire rope that is suspended from the tip of the boom or the jib so as to be able to move up and down and is inserted through the annular peripheral wall portion of the weight for the overwinding detection device, and a hook that is suspended below the weight for the overwinding detection device via the wire rope. [Effects of the Invention]

[0013] According to the present invention, it is possible to provide a weight for an overwinding detection device, an overwinding detection device, and construction machinery that can be easily attached and detached by an operator. [Brief explanation of the drawing]

[0014] [Figure 1] Figure 1 is a schematic diagram showing the boom of a crane according to an embodiment of the present invention. [Figure 2] Figure 2 is a schematic diagram showing the closed state of the weight for the overwinding detection device according to this embodiment. [Figure 3] Figure 3 is a schematic diagram showing the open state of the weight for the overwinding detection device according to this embodiment. [Figure 4] Figure 4 is an exploded view showing the weight for the overwinding detection device according to this embodiment. [Modes for carrying out the invention]

[0015] The best embodiment for carrying out the present invention will be described below with reference to the drawings. Note that the following embodiments are not intended to limit the invention as described in each claim, and not all combinations of features described in the embodiments are necessarily essential to the solution of the invention. Furthermore, the drawings are schematic diagrams with appropriate emphasis, omissions, and proportion adjustments to illustrate the present invention, and may differ from the actual shapes, positions, and proportions.

[0016] [Overall configuration of construction machinery and the construction machinery body] First, as an example of a construction machine according to an embodiment of the present invention, a crane according to this embodiment will be outlined. The crane according to this embodiment (not shown) generally comprises a so-called self-propelled crane vehicle having an upper slewing body (not shown) and a lower traveling body (not shown) as the construction machine body. The upper slewing body is connected above the lower traveling body and is configured to be able to slewing horizontally relative to the lower traveling body about a slewing axis aligned with the vertical direction.

[0017] The crane also has a boom 1, the rear end of which is attached to an upper slewing body. In this embodiment, the boom 1 is a multi-stage boom and is configured to extend and retract along its longitudinal direction. The boom 1 is configured to be able to raise and lower relative to the upper slewing body by rotating vertically around the attachment point to the upper slewing body. The boom 1 is also configured to be able to rotate horizontally relative to the lower traveling body together with the upper slewing body.

[0018] Furthermore, the crane has a jib 3, which can be attached to the tip of the boom 1. The jib 3 is configured to rotate vertically around its attachment point to the boom 1. The crane is also configured so that the jib 3 swings forward of the boom 1 by rotating vertically around its attachment point to the boom 1 from a state where it hangs vertically downward from the tip of the boom 1. In other words, the jib 3 is configured to be luffable relative to the boom 1.

[0019] Next, referring to FIG. 1, the boom 1 according to the present embodiment will be described. The boom 1 is provided with a boom head 2 at its tip. The boom head 2 is attached with a top sheave 4 and a guide sheave 5. The top sheave 4 and the guide sheave 5 are rotatable about a rotation axis along the width direction of the boom 1.

[0020] Also, the boom head 2 is attached with a loose tab bracket 8. The loose tab bracket 8 protrudes from the boom head 2 toward the front of the boom 1, and a loose tab sheave 10 is attached thereto. The loose tab sheave 10 is rotatable about a rotation axis along the width direction of the boom 1.

[0021] Further, the crane is provided with a main winch (not shown) and a supplementary winch (not shown) on the upper slewing body. During operations by the crane and the like, the main winch wire rope 12 is paid out from the main winch, and the supplementary winch wire rope 16 is paid out from the supplementary winch. Then, the main winch wire rope 12 and the supplementary winch wire rope 16 each extend along the surface of the boom 1 from the rear side to the front side of the boom 1.

[0022] And, as shown in FIG. 1, the main winch wire rope 12 and the supplementary winch wire rope 16 are suspended from the tip of the boom 1 so as to be able to move up and down. Specifically, the main winch wire rope 12 is hung in the order of the guide sheave 5 and the top sheave 4 during operations using the boom 1, and the main hook 14 is suspended from the top sheave 4 via the main winch wire rope 12. Also, in the present embodiment, the main winch wire rope 12 is inserted through an annular peripheral wall portion 34 of a main winding weight 30A described later. Further, in the present embodiment, the main hook 14 is suspended below (vertically downward in the present embodiment) the main winding weight 30A.

[0023] The auxiliary winding wire rope 16 is hung on the guide sheave 5 and the rooster sheave 10 in that order, and the sub-hook 18 is suspended from the rooster sheave 10 via the auxiliary winding wire rope 16. Therefore, the sub-hook 18 is suspended from the tip of the boom 1 via the auxiliary winding wire rope 16. In this embodiment, the auxiliary winding wire rope 16 is also inserted through the annular peripheral wall portion 34 of the auxiliary winding weight 30B, which will be described later. Furthermore, in this embodiment, the sub-hook 18 is suspended below the auxiliary winding weight 30B (downward in the vertical direction in this embodiment).

[0024] [Overall configuration of the overwinding detection device] The crane also includes an overwinding detection device 20. The overwinding detection device 20 includes a detector 22 and an overwinding detection device weight 30. The overwinding detection device weight 30 is suspended from the detector 22. In this embodiment, the crane includes a main overwinding detection device 20A for detecting overwinding of the main hook 14 and an auxiliary overwinding detection device 20B for detecting overwinding of the sub-hook 18. In this embodiment, the main overwinding detection device 20A and the auxiliary overwinding detection device 20B have similar configurations.

[0025] The main hoisting overwinding detection device 20A detects overwinding of the main hook 14 when the main hook 14 is suspended from the tip of the boom 1 (top sheave 4). The main hoisting weight 30A (overwinding detection device weight 30) of the main hoisting overwinding detection device 20A is suspended from the tip of the boom 1 and is located vertically above the main hook 14.

[0026] In this embodiment, the main hoisting weight 30A is suspended from the boom head 2 via the main hoisting detector 22A (detector 22) and a single suspension cable (sling) 24. With the main hoisting weight 30A suspended from the boom head 2, one end of the suspension cable 24 is connected to the main hoisting weight 30A. The other end of the suspension cable 24 is connected to the main hoisting detector 22A.

[0027] The main winding detector 22A is mounted on the boom head 2. The main winding detector 22A is, for example, a limit switch and outputs a detection signal indicating the detection result of overwinding of the main hook 14. In this embodiment, the main winding detector 22A outputs a detection signal indicating overwinding of the main hook 14 when the main winding weight 30A is lifted against its own weight.

[0028] For example, if the main hook 14 is excessively lifted by winding the main winding wire rope 12, the main hook 14 pushes up the main winding weight 30A from vertically downwards. Consequently, the tension from the suspension rope 24 that suspends the main winding weight 30A no longer acts on the main winding detector 22A, causing a change in the operating state of the main winding detector 22A. As a result, the main winding detector 22A outputs a detection signal indicating that overwinding of the main hook 14 has occurred.

[0029] The auxiliary winding overwinding detection device 20B detects overwinding of the sub-hook 18 when the sub-hook 18 is suspended from the tip of the boom 1 (rooster sheave 10). The auxiliary winding weight 30B (overwinding detection device weight 30) of the auxiliary winding overwinding detection device 20B is suspended from the tip of the boom 1 and is located vertically above the sub-hook 18.

[0030] In this embodiment, the auxiliary winding weight 30B is suspended from the rooster bracket 8 via the auxiliary winding detector 22B (detector 22) and a suspension cable 24. One end of the suspension cable 24 is connected to the auxiliary winding weight 30B, and the other end of the suspension cable 24 is connected to the auxiliary winding detector 22B.

[0031] The auxiliary winding detector 22B is mounted on the rooster bracket 8. Similar to the main winding detector 22A, the auxiliary winding detector 22B is, for example, a limit switch and outputs a detection signal indicating the detection result of overwinding of the sub-hook 18. Since the auxiliary winding detector 22B has the same configuration as the main winding detector 22A, the explanation of its operation when overwinding of the sub-hook 18 is detected is omitted.

[0032] Furthermore, the overwinding detection device 20B for auxiliary winding also detects overwinding of the sub-hook 18 even when the sub-hook 18 is suspended from the tip of the jib 3 (specifically, the sheave). In this case, the auxiliary winding weight 30B is suspended from the tip of the jib 3 and is positioned vertically above the sub-hook 18. Specifically, the auxiliary winding weight 30B is suspended from the tip of the jib 3 via the suspension cable 24. The auxiliary winding wire rope 16 is also inserted through the annular peripheral wall portion 34 of the auxiliary winding weight 30B.

[0033] Even when the auxiliary winding weight 30B is suspended from the tip of the jib 3, one end of the suspension cable 24 is connected to the auxiliary winding weight 30B, and the other end of the suspension cable 24 is connected to the auxiliary winding detector 22B.

[0034] [Overall configuration of the weight for the overwinding detection device] Next, with reference to Figures 2 to 4, the specific configuration of the overwinding detection device weight 30 according to this embodiment will be described. As shown in Figure 2, the overwinding detection device weight 30 comprises a weight body 32 having an annular peripheral wall portion 34, and a support shaft 60 and a biasing portion 36 incorporated into the weight body 32.

[0035] [Composition of the weight itself] The peripheral wall portion 34 of the weight body 32 is formed in a cylindrical shape and has an inner diameter through which a wire rope (for example, a main winding wire rope 12 or an auxiliary winding wire rope 16) can be inserted. The weight body 32 has a first weight piece 40 that forms part of the peripheral wall portion 34 and a second weight piece 50 that forms at least part of the remaining portion of the peripheral wall portion 34.

[0036] In this embodiment, the first weight piece 40 has a first circumferential wall portion 42 that forms a part of the circumferential wall portion 34, and the second weight piece 50 has a second circumferential wall portion 52 that forms the other part of the circumferential wall portion 34. Furthermore, the first circumferential wall portion 42 of the first weight piece 40 and the second circumferential wall portion 52 of the second weight piece 50 each have edge portions 44 and 54 that can approach or separate from each other, as shown in Figures 2 and 3.

[0037] The weight body 32 is configured such that, in a closed state where the edge portion 44 of the first peripheral wall portion 42 and the edge portion 54 of the second peripheral wall portion 52 are in contact with each other, the first weight piece 40 and the second weight piece 50 form an annular peripheral wall portion 34.

[0038] Furthermore, as shown in Figure 3, the weight body 32 is configured such that when the edges 44, 54 of the first and second peripheral wall portions 42 and 52 are spaced apart from each other, a gap g is formed within the peripheral wall portion 34 for inserting and removing a wire rope (main winding wire rope 12 in the main winding weight 30A, and auxiliary winding wire rope 16 in the auxiliary winding weight 30B).

[0039] The upper end 44a and the lower end 44b of the edge portion 44 of the first circumferential wall portion 42 are located at different positions in the circumferential direction of the circumferential wall portion 34. Specifically, the upper end 44a and the lower end 44b of the edge portion 44 are located on the circumference of the circumferential wall portion 34 at positions offset in different directions in the circumferential direction from the position opposite the center of the first shaft hole portion 46, which will be described later. Furthermore, the edge portion 44 of the first circumferential wall portion 42 extends in a straight line from the upper end 44a to the lower end 44b. That is, the edge portion 44 of the first circumferential wall portion 42 is formed in a straight line that extends diagonally with respect to the axial direction of the circumferential wall portion 34.

[0040] Preferably, the upper end 44a and the lower end 44b of the edge portion 44 have equal circumferential displacements from the position opposite the center of the first shaft hole portion 46. Furthermore, it is preferable that the vertical midpoint of the edge portion 44 (the midpoint between the upper end 44a and the lower end 44b) is located opposite the center of the first shaft hole portion 46.

[0041] Furthermore, the upper end 54a and the lower end 54b of the edge 54 of the second circumferential wall portion 52 are located at different positions in the circumferential direction of the circumferential wall portion 34. Specifically, the upper end 54a of the edge 54 of the second circumferential wall portion 52 is positioned to contact the upper end 44a of the edge 44 of the first circumferential wall portion 42 when the edge 44 of the first circumferential wall portion 42 and the edge 54 of the second circumferential wall portion 52 are brought into contact. Similarly, the lower end 54b of the edge 54 of the second circumferential wall portion 52 is positioned to contact the lower end 44b of the edge 44 of the first circumferential wall portion 42 when the edge 44 of the first circumferential wall portion 42 and the edge 54 of the second circumferential wall portion 52 are brought into contact. In other words, the edge 54 of the second circumferential wall portion 52 has a shape that is the inverted version of the edge 44 of the first circumferential wall portion 42.

[0042] Furthermore, as shown in Figure 4, the first weight piece 40 and the second weight piece 50 each have a first shaft hole 46 and a second shaft hole 56 formed in a part of their circumferential direction. The first shaft hole 46 and the second shaft hole 56 each have through holes that penetrate along the axial direction of the cylindrical circumferential wall 34, and the through holes are configured to allow the shaft portion 62 of the support shaft 60, which will be described later, to be inserted.

[0043] Specifically, the first axial hole 46 of the first weight piece 40 is provided between the edge 44 of the first circumferential wall 42 and the edge opposite to it, and the first clamping portion 48, which will be described later. Also, the second axial hole 56 of the second weight piece 50 is provided between the edge 54 of the second circumferential wall 52 and the edge opposite to it, and the second clamping portion 58, which will be described later.

[0044] In this embodiment, multiple first shaft holes 46 are provided at intervals along the axial direction of the peripheral wall 34 (two in the illustrated example). Multiple second shaft holes 56 are also provided at intervals along the axial direction of the peripheral wall 34 (two in the illustrated example). The two second shaft holes 56 are positioned so as not to interfere with the two first shaft holes 46 when the first weight piece 40 and the second weight piece 50 are combined.

[0045] Specifically, the two first shaft holes 46 are such that one first shaft hole 46 is located at the upper end of the first circumferential wall 42, and the other first shaft hole 46 is located in the middle of the first circumferential wall 42, spaced apart from the first first shaft hole 46. The two second shaft holes 56 are such that one second shaft hole 56 is located at the lower end of the second circumferential wall 52, and the other second shaft hole 56 is located in the middle of the second circumferential wall 52, at a height below the other first shaft hole 46 when the first weight piece 40 and the second weight piece 50 are combined.

[0046] Furthermore, the number and arrangement of the first shaft bore 46 and the second shaft bore 56 are not limited to those shown, and various arbitrary numbers and arrangements can be adopted.

[0047] The first weight piece 40 and the second weight piece 50, having the above configuration, have shapes that are inverted vertically along the axial direction of the annular peripheral wall portion 34.

[0048] [Structure of the support axis] Furthermore, the overwinding detection device weight 30 includes a support shaft 60, as shown in Figure 4. The support shaft 60 has a shaft portion 62 extending in the vertical direction, a suspension cable attachment portion 64 provided on the upper part of the shaft portion 62, and a connecting shaft 66 inserted through the suspension cable attachment portion 64. The shaft portion 62 has a diameter that allows it to be inserted into the first shaft hole portion 46 of the first weight piece 40 and the second shaft hole portion 56 of the second weight piece 50, and has a length at least equal to the height of the peripheral wall portion 34 (the axial length of the peripheral wall portion 34).

[0049] The suspension cable attachment section 64 has a pair of opposing wall sections, and a suspension gap is formed between these wall sections into which one end of the suspension cable 24 can be inserted. The pair of wall sections of the suspension cable attachment section 64 have through holes (not shown) formed in a direction intersecting the axial direction of the peripheral wall section 34, and the connecting shaft 66 can be inserted through these through holes.

[0050] The support shaft 60 is configured such that the suspension cable 24 can be connected to the support shaft 60, and by extension to the weight 30 for the overwinding detection device, by inserting one end of the annularly shaped suspension cable 24 into the suspension gap of the suspension cable attachment part 64, and inserting the connecting shaft 66 through the insertion hole of the suspension cable attachment part 64 and the annular end of the suspension cable 24.

[0051] Furthermore, the shaft portion 62 is provided with a through hole (not shown) at the other end for preventing it from coming loose. The support shaft 60 is configured such that the shaft portion 62 is inserted from above into the first shaft hole portion 46 of the first weight piece 40 and the second shaft hole portion 56 of the second weight piece 50, a washer 67 is inserted from the other end of the shaft portion 62, and a retaining member 68 (a cotter pin in this embodiment) can be inserted through the through hole for preventing it from coming loose. With this configuration, it is possible to prevent the support shaft 60 from falling out of the first shaft hole portion 46 of the first weight piece 40 and the second shaft hole portion 56 of the second weight piece 50.

[0052] With the shaft portion 62 of the support shaft 60 inserted through the first shaft hole portion 46 of the first weight piece 40 and the second shaft hole portion 56 of the second weight piece 50, the weight body 32 is rotated around the first shaft hole portion 46 and the second shaft hole portion 56, causing the edges 44, 54 of the first circumferential wall portion 42 and the second circumferential wall portion 52 to be separated from each other, forming a gap g.

[0053] Furthermore, the weight body 32 has an operating section for performing an operation to transition from a closed state to an open state. In this embodiment, the first weight piece 40 and the second weight piece 50 each have an operating section, which is a first clamping section 48 and a second clamping section 58, respectively. The weight body 32 is configured such that when an operator moves the first clamping section 48 and the second clamping section 58 closer together, the edges 44 and 54 of the first weight piece 40 and the second weight piece 50 are separated from each other to form an open state.

[0054] From the viewpoint of enabling easy operation, it is preferable that the first gripping portion 48 and the second gripping portion 58 be configured in a shape that can be grasped by the user with one hand. However, it is not limited to this, and for example, the first gripping portion 48 and the second gripping portion 58 may be configured in a shape that can be operated by the operator with both hands.

[0055] [Configuration of the biasing section] As shown in Figures 3 and 4, the biasing unit 36 ​​is configured to bias the first weight piece 40 and the second weight piece 50 so that their edges 44 and 54 come into contact with each other, creating a closed state.

[0056] In this embodiment, the biasing portion 36 is a torsion coil spring, and the weight 30 for the overwinding detection device is equipped with two biasing portions 36 (torsion coil springs). However, it is not limited to this, and the number of biasing portions 36 may be one or three or more.

[0057] The biasing section 36 is constructed such that the opening of the coil portion 36a of the torsion coil spring faces the first shaft hole 46 of the first weight piece 40 and the second shaft hole 56 of the second weight piece 50, through which the shaft portion 62 of the support shaft 60 is inserted. The biasing section 36 is also constructed such that the arm portion (end portion) 36b of the torsion coil spring faces the extending direction of the first clamping portion 48 of the first weight piece 40 and the second clamping portion 58 of the second weight piece 50. The arm portion 36b is in contact with the first clamping portion 48 and the second clamping portion 58.

[0058] With this configuration, when an operator applies a load and brings the first clamping portion 48 of the first weight piece 40 and the second clamping portion 58 of the second weight piece 50 closer together, the arm portion 36b moves closer, causing torsion in the coil portion 36a and generating stress. Subsequently, when the operator stops applying load to the first clamping portion 48 and the second clamping portion 58, the restoring force of the coil portion 36a causes the arm portion 36b to move apart, biasing the first clamping portion 48 and the second clamping portion 58, which are in contact with the arm portion 36b, to move apart from each other. Then, when the first clamping portion 48 and the second clamping portion 58 move apart, the edges 44 and 54 of the first weight piece 40 and the second weight piece 50 move closer together, and finally the edges 44 and 54 come into contact with each other in a closed state.

[0059] Furthermore, from the viewpoint of enabling easy operation, it is preferable that the biasing portion 36 is configured to exert a biasing force sufficient to allow the operator to easily bring the first gripping portion 48 of the first weight piece 40 and the second gripping portion 58 of the second weight piece 50 closer together with their fingertips.

[0060] However, it is not limited to this. For example, the biasing portion 36 may be configured to exert a biasing force such that the edges 44 and 54 of the first weight piece 40 and the second weight piece 50 do not separate unless the worker brings the first clamping portion 48 and the second clamping portion 58 together with both hands, from the viewpoint of preventing the wire rope from falling off.

[0061] The overwinding detection device weight 30, having the above configuration, has fewer parts and can therefore be lighter than conventional overwinding detection device weights. The overwinding detection device weight 30 according to this embodiment has the advantage of reducing the burden on the operator during attachment and detachment, and making it easier to attach and detach the overwinding detection device weight 30, due to its lighter weight. It is preferable that the weight of the overwinding detection device weight 30 be set considering the prevention of false detection by the overwinding detection device 20 due to disturbances, etc.

[0062] [Advantages of the weight for the overwinding detection device, the overwinding detection device, and the construction machine according to this embodiment] As described above, the weight 30 for the overwinding detection device according to this embodiment comprises a weight body 32 having an annular peripheral wall portion 34 and a biasing portion 36 incorporated into the weight body 32, the weight body 32 having a first weight piece 40 that forms a part of the peripheral wall portion 34 and a second weight piece 50 that forms at least a part of the remainder of the peripheral wall portion 34, the first weight piece 40 and the second weight piece 50 have edge portions 44, 54 that can approach or separate from each other, and the first way In an open state where the edges 44, 54 of the first weight piece 40 and the second weight piece 50 are spaced apart from each other, a gap g is formed in the peripheral wall 34 for inserting and removing a wire rope (in this embodiment, the main winding wire rope 12 or the auxiliary winding wire rope 16). The biasing unit 36 ​​is configured to bias the first weight piece 40 and the second weight piece 50 so that their edges 44, 54 come into contact with each other in a closed state.

[0063] Furthermore, the weight 30 for the overwinding detection device according to this embodiment has the advantage that, by having such a configuration, the wire rope can be inserted into and removed from the inside of the peripheral wall portion 34 through the gap g simply by separating the end portions 44 and 54 of the first weight piece 40 and the second weight piece 50, so that the operator can easily attach and detach the weight 30 for the overwinding detection device to the wire rope without using any tools. In addition, after the wire rope has been inserted or removed, the biasing force of the biasing portion 36 allows it to automatically transition from the open state to the closed state, so the operator only needs to perform the operation to open it, insert or remove the wire rope, and then release their hand, which makes it even easier to attach and detach the weight 30 for the overwinding detection device to the wire rope. Moreover, the weight 30 for the overwinding detection device according to this embodiment has the advantage that, since there is no need to attach or detach any parts when inserting or removing the wire rope, there is no risk of losing any of the parts that make up the weight 30 for the overwinding detection device.

[0064] Furthermore, in the weight 30 for the overwinding detection device according to this embodiment, the weight body 32 has an operating section (a first gripping section 48 and a second gripping section 58 in this embodiment) for performing an operation to transition from a closed state to an open state. With this configuration, the transition operation can be performed more easily compared to the case where the transition operation is performed directly by grasping a part of the peripheral wall portion 34 such as the edge portions 44, 54 of the first weight piece 40 and the second weight piece 50, thus having the advantage of being able to attach and detach the weight 30 for the overwinding detection device more easily to the wire rope. In addition, it has the advantage of preventing injuries that may occur when an operator gets their fingers caught in the gap g between the edge portions 44, 54.

[0065] Furthermore, in the weight 30 for the overwinding detection device according to this embodiment, the upper ends 44a, 54a and lower ends 44b, 54b of the edge portions 44, 54 of the first weight piece 40 and the second weight piece 50 are located at different positions in the circumferential direction of the peripheral wall portion 34. With this configuration, even when the wire rope inserted through the peripheral wall portion 34 moves radially across the peripheral wall portion 34 and a force acting radially outward from the wire rope on the peripheral wall portion 34 of the weight body 32, the wire rope is less likely to get stuck between the contacting edge portions 44, 54, and the edge portions 44, 54 are less likely to separate, which is a further advantage.

[0066] Furthermore, in the overwinding detection device weight 30 according to this embodiment, the first weight piece 40 and the second weight piece 50 have shapes that are inverted vertically along the axial direction of the peripheral wall portion 34. By having such a configuration, for example, when the first weight piece 40 and the second weight piece 50 are manufactured by casting, they can be manufactured using the same mold, which has the further advantage of reducing the manufacturing cost of the overwinding detection device weight 30. In addition, the inventory management costs for the parts of the overwinding detection device weight 30 can also be reduced.

[0067] [Differentiation] Although preferred embodiments of the present invention have been described above, the technical scope of the present invention is not limited to the embodiments described above. Various modifications or improvements can be made to the embodiments described above.

[0068] For example, in the embodiment described above, the weight body 32 was described as having an operating section (a first clamping section 48 and a second clamping section 58 in this embodiment) for performing an operation to transition from a closed state to an open state, but it is not limited to this, and the weight body 32 does not have to have an operating section. Also, in the embodiment described as having operating sections on both the first weight piece 40 and the second weight piece 50, the weight body 32 is not limited to this. For example, only one of the first weight piece 40 and the second weight piece 50 may have an operating section.

[0069] In the embodiments described above, the weight 30 for the overwinding detection device was described as having upper ends 44a, 54a and lower ends 44b, 54b of the edge portions 44, 54 of the first weight piece 40 and the second weight piece 50 being at different positions in the circumferential direction of the peripheral wall portion 34. However, the invention is not limited to this, and various arbitrary configurations can be adopted. For example, in the weight 30 for the overwinding detection device, the upper ends 44a, 54a and lower ends 44b, 54b of the edge portions 44, 54 may be at the same position in the circumferential direction of the peripheral wall portion 34. Also, the boundary between the edge portion 44 of the first weight piece 40 and the edge portion 54 of the second weight piece 50 may be along the axial direction of the peripheral wall portion 34. In other words, the edge portions 44, 54 of the first weight piece 40 and the second weight piece 50 may be in a straight line along the vertical direction. Furthermore, the edges 44 and 54 of the first weight piece 40 and the second weight piece 50 are not limited to being straight, but can be any shape such as wavy, jagged, or gear-shaped.

[0070] In the embodiments described above, the weight 30 for the overwinding detection device was described as having a first weight piece 40 and a second weight piece 50 that are inverted vertically along the axial direction of the annular peripheral wall portion 34, but it is not limited to this. The first weight piece 40 and the second weight piece 50 do not have to have a shape that is inverted vertically along the axial direction of the annular peripheral wall portion 34.

[0071] In the embodiments described above, the weight 30 for the overwinding detection device was described as having a support shaft 60, but it is not limited to this. For example, the weight 30 for the overwinding detection device may be configured such that at least one of the first weight piece 40 and the second weight piece 50 has a shaft portion, and the other has a shaft hole into which the shaft portion is inserted.

[0072] In the embodiments described above, the peripheral wall portion 34 of the overwinding detection device weight 30 was described as being formed by two weight pieces (a first weight piece 40 and a second weight piece 50). However, it is not limited to this, and other weight pieces such as a third weight piece (not shown) may be further included, and the remainder of the peripheral wall portion 34 may be formed by a plurality of weight pieces.

[0073] In the embodiments described above, the crane is equipped with a main hoisting overwind detection device 20A and an auxiliary hoisting overwind detection device 20B, and the main hoisting overwind detection device 20A and the auxiliary hoisting overwind detection device 20B have been described as having similar configurations, but the crane is not limited to this. The crane does not need to be equipped with multiple overwind detection devices 20. Also, the main hoisting overwind detection device 20A and the auxiliary hoisting overwind detection device 20B may have different configurations. For example, the main hoisting overwind detection device 20A may be equipped with an overwind detection device weight 30 according to this embodiment, and the auxiliary hoisting overwind detection device 20B may be equipped with a conventional overwind detection device weight, or vice versa. Furthermore, one overwind detection device weight 30 may be used for both the main hoisting overwind detection device 20A and the auxiliary hoisting overwind detection device 20B.

[0074] In the embodiments described above, the weight 30 for the overwinding detection device was described as being suspended from the boom head 2 via a single suspension cable 24, but it is not limited to this. For example, the weight 30 for the overwinding detection device may be suspended by two or more suspension cables 24.

[0075] In the embodiments described above, the biasing portion 36 was described as a torsion coil spring, but it is not limited to this. The biasing portion 36 can be any configuration as long as it is capable of biasing the first weight piece 40 and the second weight piece 50 so that their edges 44, 54 come into contact with each other in a closed state. For example, the biasing portion 36 may be a compression coil spring or the like.

[0076] In the embodiments described above, the weight body 32 was described as being configured to open when the operator moves the first clamping portion 48 and the second clamping portion 58 closer together, but it is not limited to this. For example, the weight body 32 may be configured to open when the operator moves the first clamping portion 48 and the second clamping portion 58 further apart.

[0077] In the embodiments described above, the crane was described as a so-called self-propelled crane equipped with an upper slewing body and a lower traveling body, but it is not limited to this. The crane may be, for example, an overhead crane, a bridge crane, a jib crane, an unloader, a cable crane, a jib climbing crane, etc.

[0078] In the embodiments described above, the crane was described as having a jib 3, but it is not limited to this, and the crane does not need to have a jib 3.

[0079] In the embodiment described above, the support shaft 60 was described as being configured such that, after inserting the shaft portion 62 through the first shaft hole portion 46 of the first weight piece 40 and the second shaft hole portion 56 of the second weight piece 50 from above, a washer 67 is inserted from the other end of the shaft portion 62, and a retaining member 68 can be inserted through the retaining through hole. However, the invention is not limited to this configuration. The shaft portion 62 may have a retaining through hole at one end (the end on the suspension cable attachment portion 64 side) and a rib portion extending radially from the other end of the shaft portion 62. That is, the support shaft 60 may be configured such that, after inserting the shaft portion 62 and the suspension cable attachment portion 64 through the first shaft hole portion 46 and the second shaft hole portion 56 from below, a washer 67 is inserted from one end of the shaft portion 62, and a retaining member 68 can be inserted through the retaining through hole. [Explanation of Symbols]

[0080] 1. Boom 2 Boom Head 3 Jib 4 Top Seeb 5 Guide Sheaves 8 Rooster Brackets 10 Rooster Sieve 12 Main winding wire rope 14 Main Hooks 16. Supplemental wire rope 18 Sub-hooks 20 Overwinding detection device 20A Overwinding Detection Device for Main Winding 20B Overwinding detection device for auxiliary winding 22 detectors 22A Main winding detector 22B Supplemental winding detector 24 sling 30 Weights for overwinding detection device 30A Main winding weight 30B Replacement weight for winding 32 Weight Body 34 Peripheral wall part 36. Encouraging part 36a Coil section 36b Arm section 40 First weight piece 42 1st peripheral wall part 44 Edge 46 First shaft bore 48 First clamping part 50 Second weight piece 52 Second peripheral wall part 54 Edge 56 Second shaft bore 58 Second clamping part 60 Spindle 62 Shaft section 64 Hanging rope attachment part 66 connecting shafts 67 Washer 68 Retaining member g gap

Claims

1. A weight body having an annular peripheral wall, The biasing part incorporated into the weight body and Equipped with, The weight body comprises a first weight piece that forms a part of the peripheral wall and a second weight piece that forms at least a part of the remaining peripheral wall. The first weight piece and the second weight piece have edges that can move closer to or further apart from each other, and are configured such that when the edges of the first weight piece and the second weight piece are separated from each other, a gap is formed in the peripheral wall that allows a wire rope to be inserted and removed. The biasing unit is configured to bias the first weight piece and the second weight piece such that their edges are in contact with each other in a closed state. A weight for an overwinding detection device characterized by the following features.

2. The weight body has an operating section for performing an operation to transition from the closed state to the open state. The weight for the overwinding detection device according to feature 1.

3. The upper end and the lower end of the aforementioned edge are located at different positions in the circumferential direction of the peripheral wall. A weight for an overwinding detection device according to claim 1 or 2.

4. The first weight piece and the second weight piece have shapes that are inverted vertically along the axial direction of the peripheral wall portion. The weight for the overwinding detection device according to feature 3.

5. A weight for an overwinding detection device according to claim 1 or 2, When the weight for the overwinding detection device is lifted against its own weight, a detector outputs a detection signal indicating overwinding of a hook suspended below the weight via the wire rope. Equipped with An overwinding detection device characterized by the following features.

6. The overwinding detection device according to claim 5, A construction machine body having at least one of a boom and a jib, a wire rope suspended from the tip of the boom or the jib so as to be able to move up and down and inserted through the annular peripheral wall of the overwind detection device weight, and a hook suspended below the overwind detection device weight via the wire rope. Equipped with A construction machine characterized by the following features.

Images