JP7694965B2 - Lifting equipment - Google Patents

Description

The present invention relates to a lifting device used to lift heavy objects.

As an example of such a hoisting device, a hoisting pulley is known, which includes a rope that connects to the object to be hoisted and a main body that suspends the object via the rope, as disclosed in Patent Document 1.

The main body comprises a pair of snatch plates arranged opposite each other, a sling attached between the pair of snatch plates for hanging on a lifting machine, a rope sheave around which the rope is wound, the rope sheave being rotatably attached between the pair of snatch plates, and a stop means for stopping the rotation of the rope sheave.

A sheave shaft is inserted through the rope sheave and the pair of snatch plates. This sheave shaft is configured so that its position can be changed in the vertical direction relative to the snatch plates, and is placed on a spring attached to the snatch plates so that it can expand and contract in the vertical direction.

Therefore, unless a load greater than the spring force is applied to the rope sheave, it is positioned toward the upper side of the snatch plate, and when a load greater than the spring force is applied, its position relative to the snatch plate is changed from the upper side to the lower side.

The stopping means has inner corrugated teeth formed on the inner peripheral surface of the hollow (annular) rope sheave, and a fan-shaped body fixed to the inside of the snatch plate so as to face the inner corrugated teeth from below, and outer corrugated teeth that mesh with the inner corrugated teeth are formed on the upper surface of the fan-shaped body.

When using the above-described hoisting pulley to hoist an object, the rope is wound around the outer periphery of the rope sheave, both ends are connected to the object, and the hoisting hardware is hung on the hoist.

In this state, the lifting pulley is lifted by the lifting machine, but if the center of gravity of the object to be lifted deviates from the lifting center line (an imaginary line that passes through the position where the main body is lifted and extends vertically) when the lifting machine begins to lift the main body, the wheel will rotate and the main body will move toward the center of gravity of the object to be lifted, and the position of the main body will automatically be adjusted so that the center of gravity of the object to be lifted and the lifting center line overlap.

When the load is lifted off the ground, the rope sheave is subjected to a load greater than the spring force, causing the position of the rope sheave relative to the snatch plate to change from the upper side to the lower side. As a result, the internal corrugated teeth and external corrugated teeth mesh and the rope sheave is fixed to the snatch plate so that it does not rotate. This makes it possible to hoist the load without changing the position of the main body relative to the load.

Special Publication No. 49-1823

However, in a hoist pulley with the above configuration, the rope sheave is free to rotate until the internal and external corrugated teeth mesh and the rope sheave is fixed to the snatch plate to prevent it from rotating. This means that the rope sheave can rotate at unintended times, making it difficult to handle.

In light of this situation, the objective of the present invention is to provide a hanging device that is easy to use.

The sling of the present invention comprises:
A long chain that is connected to an object to be lifted;
A hoisting tool main body that suspends an object to be hoisted via the chain,
the hoisting device main body has an exterior part including a hook part to be hung on a hoisting machine, a wheel rotatably attached to the exterior part, the wheel having an engagement part formed on an outer circumferential side surface to engage with the chain, a locking mechanism switchable between a state in which the rotation of the wheel is restricted and a state in which the restriction on the rotation of the wheel is released, and a brake mechanism that brakes the rotation of the wheel;
The wheel is movable up and down relative to the exterior part,
the locking mechanism includes a biasing means for biasing the wheel upward while allowing the wheel to move up and down, and a pair of meshing portions disposed opposite each other in the vertical direction, the pair of meshing portions moving toward and away from each other as the wheel is moved up and down relative to the exterior portion,
One of the pair of meshing portions is fixed to the wheel,
The other of the pair of meshing portions is fixed to the exterior portion,
The brake mechanism includes a brake shoe that presses against the wheel, and an adjustment means that adjusts the pressing force of the brake shoe against the wheel.

To lift an object using the above-mentioned lifting device, a chain with both ends connected to the object is hung on a wheel, and the hanging part of the exterior is hung on a lifting machine.

As long as the wheel is not subjected to a load greater than the biasing force of the biasing means, the wheel can rotate if an external force exceeding the braking force of the brake mechanism is applied, so the position of the sling body can be changed along the chain.

When the exterior is lifted by the hoist and a load greater than the biasing force of the biasing means is applied to the wheel, the wheel tries to remain in place while the exterior continues to be lifted, causing the wheel's position relative to the exterior to change from the upper side to the lower side. As a result, the meshing portion fixed to the wheel and the meshing portion fixed to the exterior mesh with each other, restricting the rotation of the wheel.

Furthermore, with the sling configured as above, the rotation of the wheel can be braked by increasing the pressing force of the brake shoe against the wheel using the adjustment means, which prevents the wheel from rotating at an unintended timing, thereby improving ease of use.

In the sling of the present invention,
The wheel has an outer circumferential side surface formed with a fitting groove into which the chain fits and a brake abutment portion with which the brake shoe abuts,
The brake contact portion may be formed at a bottom portion of the fitting groove.

With the above-mentioned configuration of the sling, the fitting groove into which the chain fits and the brake abutment part against which the brake shoe abuts are formed as one unit, making it possible to perform the function of making it difficult for the wheel to rotate with a simple structure.

In the sling of the present invention,
The adjustment means has a lever exposed to the outside of the exterior body,
The lever may be configured so that its position changes in response to a pressing force of the brake shoe against the wheel.

With a sling device of the above configuration, the strength of the braking force that the brake mechanism is applying to the rotational motion of the wheel can be confirmed by looking at the direction of the lever, which makes it easier to use.

In the sling of the present invention,
The hoist body has a switching restriction means for restricting switching of the locking mechanism to a state in which rotation of the wheel is restricted,
The switching control means may be provided on the exterior portion and configured to directly or indirectly embrace the wheel from below when the exterior portion is tilted toward one end or the other end of the chain.

When the exterior part of the hoisting device configured as described above is pulled diagonally upward by the hoisting machine (when the exterior part is pulled diagonally), the wheel is directly or indirectly held from below by the switching restriction means, and the wheel cannot be repositioned downward relative to the exterior part.

As a result, the locking mechanism cannot be switched to a state that restricts the rotation of the wheels, so by leaving the wheels in a rotatable state, the object to be lifted can be prevented from being lifted while being subjected to a lateral force, making it possible to lift the object safely.

As described above, the sling of the present invention has the excellent effect of being easy to handle.

FIG. 1 is an external view of a sling according to an embodiment of the present invention. FIG. 2 is a front view of a suspender main body of the suspender according to the embodiment. FIG. 3 is a front view of a portion of the sling body of the sling according to the embodiment, excluding an exterior part. FIG. 4 is a partial cross-sectional view of FIG. 5A and 5B are explanatory diagrams of the wheel of the sling according to the embodiment, where FIG. 5A is a view taken along the arrow V in FIG. 4 and is a cross-sectional view taken along the line BB in FIG. Figure 6 is an explanatory diagram of the operation of restricting the rotation of the wheel by the locking mechanism in the hanging device of the same embodiment, where (a) is an explanatory diagram of the state before the rotation of the wheel is restricted by the locking mechanism, and (b) is an explanatory diagram of the state after the rotation of the wheel is restricted by the locking mechanism. Figure 7 is an explanatory diagram of the operation of limiting the operation of the locking mechanism by the switching limiting means of the hanging device in the same embodiment, where (a) is an explanatory diagram of the state before the operation of the locking mechanism is limited by the switching limiting means, and (b) is an explanatory diagram of the state after the operation of the locking mechanism is limited by the switching limiting means. FIG. 8 is a perspective view of a rotation shaft of the suspender according to the embodiment. FIG. 9 is an explanatory diagram of the hanging tool according to the embodiment in use. FIG. 10 is an explanatory diagram of the hanging tool according to the embodiment in use. FIG. 11 is an explanatory diagram of a sling according to another embodiment of the present invention. FIG. 12 is an explanatory diagram of the locking mechanism of the sling according to the embodiment.

The following describes a sling device according to one embodiment of the present invention with reference to the attached drawings. Note that the up-down and left-right directions are based on the state shown in Figures 1 to 4.

As shown in FIG. 1, the hoist 1 according to this embodiment is a long chain 2 that can be connected at both ends to an object to be hoisted (e.g., a heavy object), and includes a hoist body 3 that suspends the object to be hoisted via the chain 2.

At both ends of the chain 2 in the longitudinal direction, a connecting means 20 such as a coupling, hook, or shackle is provided, and this connecting means 20 connects both ends of the chain 2 to the object to be suspended.

The chain 2 of this embodiment is constructed by connecting multiple rings 200. Each ring 200 is elliptical and annular, and has a pair of parallel straight sections 200a and an arc section 200b that connects the end of one adjacent straight section 200a to the end of the other straight section 200a.

As shown in FIG. 2, the hoisting device main body 3 has an exterior part 30 including a hook part 300 to be hung on a hoisting machine (e.g., a crane, etc.), a wheel 31 to which a chain 2 is hung on the outer peripheral side and which is rotatably attached to the exterior part 30, a locking mechanism 32 that can be switched between a state in which the rotation of the wheel 31 is restricted (locked state) and a state in which the restriction on the rotation of the wheel 31 is released (unlocked state), a brake mechanism 33 that brakes the rotation of the wheel 31, and a switching restriction means 34 that prevents the locking mechanism 32 from switching from the locked state to the unlocked state.

In this embodiment, the exterior part 30 has a pair of plates 301 arranged opposite each other with a gap between them, and a roller shaft 302 arranged between the pair of plates 301.

One axial end of the roller shaft 302 is attached to one plate 301, and the other axial end is attached to the other plate 301. In the sling 1 of this embodiment, the roller shaft 302 constitutes the hanging part 300.

The wheel 31 is disposed between a pair of plates 301. A rotation axis P1 is inserted through a through hole in the center of the wheel 31 and through each of the pair of plates 301 (specifically, through-holes 320 (described later) formed on each of the pair of plates 301), so that the wheel 31 is rotatably attached to the exterior 30.

As shown in FIG. 4, the outer peripheral side of the wheel 31 in this embodiment is formed with a fitting groove 310 into which the chain 2 fits, and a brake abutment portion 311 against which the brake shoe 35 (described later) abuts.

As shown in FIG. 5(a), the fitting groove 310 is formed so as to open on the outer peripheral side surface of the wheel 31, and is also formed so as to be continuous around the entire outer peripheral side surface of the wheel 31.

The fitting groove 310 in this embodiment has a deep groove portion 310a formed on the outer peripheral side surface of the wheel 31, the deep groove portion 310a being formed so as to be continuous around the entire circumference of the outer peripheral side surface of the wheel 31, and a plurality of shallow groove portions 310b formed on the outer peripheral side surface of the wheel 31, the plurality of shallow groove portions 310b being formed so as to be aligned along the circumferential direction of the wheel 31.

The depth of each of the shallow grooves 310b is shallower than the deep grooves 310a (see FIG. 5(b)).

In addition, each of the shallow groove sections 310b has a pair of shallow groove forming sections 310c that are formed side by side via the deep groove section 310a in the thickness direction of the wheel 31.

One of the pair of shallow groove forming portions 310c is continuous with the deep groove portion 310a on one side in the thickness direction of the wheel 31 (one side in the groove width direction of the deep groove portion 310a), and the other of the pair of shallow groove forming portions 310c is continuous with the deep groove portion 310a on the other side in the thickness direction of the wheel 31 (the other side in the groove width direction of the deep groove portion 310a).

Each of the shallow grooves 310b is formed so that they are spaced apart in the circumferential direction of the wheel 31.

As shown in FIG. 5(b), the ring 200 is configured to enter the shallow groove portion 310b in a horizontal orientation (horizontal to the outer peripheral side surface of the wheel 31), and the ring 200 is configured to enter the deep groove portion 310a in a vertical orientation (vertical to the outer peripheral side surface of the wheel 31). Therefore, when the chain 2 is hung on the wheel 31, the shallow groove portion 310b and the horizontally oriented ring 200 engage with each other in the circumferential direction of the wheel 31.

The brake contact portion 311 is formed by the deep groove portion 310a. In other words, the deep groove portion 310a serves as both a portion for receiving the vertically oriented ring 200 and a portion for receiving the brake mechanism 33 (the brake shoe 330 described later).

The bottom surface of the brake abutment portion 311 is formed so that its radial cross section is linear, and the brake shoe 330 (described later) abuts against this bottom surface. The chain 2 is hung on the upper side of the wheel 31, but the lower side of the wheel 31 is left open, so that the brake shoe 330 can abut against the bottom surface of the brake abutment portion 311 from the lower side of the wheel 31.

As shown in FIG. 3, the locking mechanism 32 includes an axis insertion portion 320 formed in the exterior portion 30, through which the rotation axis P1 inserted in the wheel 31 is inserted while allowing it to move up and down, a biasing means 321 that biases the wheel 31 upward while allowing the wheel 31 to move up and down, and a pair of meshing portions 322, 323 that are arranged opposite each other in the vertical direction and that come into contact with and separate from each other as the position of the wheel 31 relative to the exterior portion 30 is changed in the vertical direction.

The shaft insertion portion 320 is configured as a long hole (long hole extending in the vertical direction) formed in the exterior portion 30. Therefore, when the rotation shaft P1 is inserted into the shaft insertion portion 320, the rotation shaft P1 is allowed to move in the vertical direction, while the movement of the rotation shaft P1 in the left-right direction is restricted. And, when the rotation shaft P1 is inserted into the shaft insertion portion 320, the wheel 31 through which the rotation shaft P1 is inserted is also allowed to move in the vertical direction, while the movement of the wheel 31 in the left-right direction is restricted.

The biasing means 321 receives the rotating shaft P1 from below while it is inserted into the shaft insertion portion 320. In addition, the biasing means 321 biases the rotating shaft P1 upward while allowing the rotating shaft P1 to move up and down in the shaft insertion portion 320, so the wheel 31 through which the rotating shaft P1 is inserted is also receiving an upward biasing force while allowing the wheel 31 to move up and down.

Therefore, when a load greater than the biasing force of the biasing means 321 is applied when the exterior part 30 is lifted by the hoisting machine, the wheel 31 changes its position relative to the exterior part 30 downward, and when the load goes from being greater than the biasing force of the biasing means 321 to being less than the biasing force, the wheel 31 changes its position relative to the exterior part 30 upward (returns).

The biasing force of the biasing means 321 is set to a level that keeps the pair of interlocking portions 322, 323 from interlocking with each other until the suspended object is lifted away from the ground surface as the sling body 3 is lifted.

The biasing means 321 may be formed using an elastic body that can be elastically deformed, such as a torsion spring. In this case, the biasing means 321 includes a spiral mounting portion 321a through which a fixing shaft is inserted, and a pair of extension portions 321b extending from the mounting portion 321a, with one of the extension portions 321b pushing up the rotation axis P1.

Of the pair of meshing portions 322, 323, one meshing portion 322 is a wheel side meshing portion 322 that is attached to the wheel 31 by bolting, and the other meshing portion 323 is an exterior side meshing portion 323 that is attached to the exterior portion 30 and is immovable up and down relative to the exterior portion 30.

The wheel side meshing portion 322 and the exterior side meshing portion 323 are formed with teeth 3220, 3230 that mesh with each other.

The wheel-side meshing portion 322 is formed in a disk shape, and the teeth 3220 are formed on the entire outer circumference of the wheel-side meshing portion 322. The wheel-side meshing portion 322 may be fixed to the front or back surface of the wheel 31.

Furthermore, since the wheel side meshing portion 322 is concentric with the wheel 31, when the position of the wheel 31 relative to the exterior part 30 has not been changed downward by the biasing force of the biasing means 321, the distance between the teeth 3220 of the wheel side meshing portion 322 and the teeth 3230 of the exterior side teeth 323 remains constant even when the wheel 31 rotates.

The exterior side meshing portion 323 is arranged in a position aligned below the wheel side meshing portion 322 and is fixed to the exterior portion 30 (the inner surface of the plate 301 in this embodiment) with the teeth portion 3230 facing the teeth portion 3220 of the wheel side meshing portion 322.

Here, the positional relationship between the wheel side meshing portion 322 and the exterior side meshing portion 323 will be described. As shown in FIG. 6(a), the exterior side meshing portion 323 is disposed inside the wheel side meshing portion 322. Furthermore, when the wheel 31 is not subjected to a load greater than the biasing force of the biasing means 321, the wheel 31 is disposed on the upper side relative to the exterior portion 30, so that the exterior side meshing portion 323 faces the wheel side meshing portion 322 and is disposed at a position away from the wheel side meshing portion 322 downward.

When a load greater than the biasing force of the biasing means 321 is applied to the wheel 31 during lifting of the sling body 3, the wheel side meshing portion 322 remains in place together with the wheel 31, while the exterior side meshing portion 323 is lifted upward together with the exterior part 30. As a result, as shown in FIG. 6(b), the position of the wheel 31 relative to the exterior part 30 changes from the upper side to the lower side, the exterior side meshing portion 323 approaches the wheel side meshing portion 322, and the teeth 3230 of the exterior side meshing portion 323 mesh with the teeth 3220 of the wheel side meshing portion 322.

The toothed portion 3220 and the toothed portion 3230 can be configured with rounded wavy teeth or triangular teeth, but if the toothed portion 3220 and the toothed portion 3230 are formed with triangular teeth as in this embodiment, it is easier to ensure the contact area between the toothed portion 3220 and the toothed portion 3230 in the circumferential direction of the wheel 31, and the effect of restricting the rotation of the wheel 31 by the meshing of the toothed portion 3230 and the toothed portion 3230 can be enhanced, and the rotation of the wheel 31 can be minimized. As a result, the position of the hoisting tool main body 3 relative to the suspended object during lifting (for example, the position of the lifting center line of the hoisting tool main body 3 relative to the center of gravity of the suspended object) is less likely to shift.

In this way, the sling body 3 of this embodiment is configured to switch between a state in which the rotation of the wheel 31 is restricted and a state in which the restriction on the rotation of the wheel 31 is released, depending on the position of the wheel 31 relative to the exterior part 30.

As shown in FIG. 4, the brake mechanism 33 has a brake shoe 330 that slides against the wheel 31, and an adjustment means 331 that adjusts the pressing force of the brake shoe 330 against the wheel 31.

The brake shoe 330 is constantly in contact with the bottom surface of the brake contact portion 311, and is configured to generate a braking force against the rotation of the wheel 31 when the wheel 31 is about to rotate or when the wheel 31 has rotated. The brake shoe 330 is made of a material that can generate a frictional force between itself and the bottom surface of the brake contact portion 311, and for example, steel, resin material, sintered material, etc. can be used.

The adjustment means 331 has a push operation part 3310 that pushes the brake shoe 330 inward in the radial direction of the wheel 31, and an adjustment operation part 3311 that adjusts the pressing force of the push operation part 3310 against the brake shoe 330.

The pushing operation part 3310 is configured to move in a direction toward and away from the brake shoe 330 in the radial direction of the wheel 31, and the adjustment operation part 3311 is the part that is operated when moving the pushing operation part 3310 in a direction toward or away from the wheel 31.

The push operation unit 3310 has a push operation shaft 3310a, one end of which abuts against the brake shoe 330, a shaft holding unit 3310b that holds the operation shaft 3310a in a state in which it can slide toward and away from the wheel 31, and a shaft biasing unit 3310c that biases the operation shaft 3310a in a direction away from the wheel 31.

The adjustment operation unit 3311 is configured as a long and thin lever. The adjustment operation unit 3311 is attached such that the intermediate portion between one end and the other end in the longitudinal direction is rotatable relative to the exterior unit 30.

One end of the adjustment operation unit 3311 in the longitudinal direction is configured as an operation unit 3311a that is pulled by the user, and the other end of the adjustment operation unit 3311 in the longitudinal direction is configured as an axis pressing unit 3311b that presses the pushing axis 3310a toward the wheel 31.

In the adjustment means 331 of this embodiment, when the operation part 3311a is pulled downward, the entire adjustment operation part 3311 rotates and the shaft pressing part 3311b moves upward. When the shaft pressing part 3311b moves upward, it presses the pushing operation shaft 3310a toward the wheel 31 side (brake shoe 330 side), so that the pushing operation shaft 3310a presses the brake shoe 330, thereby suppressing the rotation of the wheel 31.

When the operating state of the operating part 3311a is released, the pushing shaft 3310a is pushed by the shaft biasing part 3310c and moves in a direction away from the wheel 31, and when the shaft pushing part 3311b is pushed back (pushed down) by this pushing shaft 3310a, the adjustment means 331 rotates and returns to its original state.

In addition, since the adjustment operation part 3311 in this embodiment is configured as a lever as described above, the position of the pushing operation part 3310 (i.e., the pressing force against the brake shoe 330) can be adjusted according to the degree to which the adjustment operation part 3311 is turned (pulled).

The shaft pressing portion 3311b may be operated by the user by holding it directly in his/her hand, or by pulling it using a stick or string attached to it.

As shown in FIG. 7(a), the switching restriction means 34 has a movement restriction part 340 that restricts the downward movement of the wheel 31 relative to the exterior part 30, and a connecting shaft 341 that rotatably connects the movement restriction part 340 to the exterior part 30.

The movement restriction section 340 is configured to allow the position of the wheel 31 relative to the exterior section 30 to be changed downward in an upright state in which the upper and lower ends of the exterior section 30 are aligned vertically, and to prevent the position of the wheel 31 relative to the exterior section 30 from being changed downward in an inclined state in which the positions of the upper and lower ends of the exterior section 30 are misaligned in the direction in which one end and the other end of the chain 2 are aligned.

The movement restriction unit 340 in this embodiment is configured to engage (embrace) the rotation axis P1 from below when the exterior unit 30 switches from the upright state to the inclined state, as shown in FIG. 7(b), and to move away from the rotation axis P1 when the exterior unit 30 switches from the inclined state to the upright state, as shown in FIG. 7(a).

The movement restriction part 340 in this embodiment has a rotation connection part 3400 that is rotatably connected to the exterior part 30 at a position spaced upward from the rotation axis P1, and a pair of engagement claw parts 3401 that extend from the rotation connection part 3400 and are arranged side-by-side with a gap between them.

A connecting shaft 341 is inserted through the rotating connecting part 3400 and the plate 301, so that the rotating connecting part 3400 is configured to be rotatable around the connecting shaft 341. Therefore, the rotating connecting part 3400 swings like a pendulum relative to the exterior part 30.

The rotary coupling part 3400 is disposed at a location where the rotary axis P1 is interposed between a pair of engaging claw parts 3401. In this embodiment, the rotary coupling part 3400 is disposed overlapping the outer surface of the plate 301. In addition, a coupling shaft 341 is inserted between the rotary coupling part 3400 and the plate 301, so that the rotary coupling part 3400 is configured to be freely rotatable with respect to the plate 301 (exterior part 30).

A return portion 3401a is formed at the tip of the engaging claw portion 3401, protruding toward the adjacent engaging claw portion 3401.

As shown in FIG. 8, the rotating shaft P1 of this embodiment includes an axle body P10 that is inserted into the center of the wheel 31, a guided axle portion P11 that extends outward from the axle body P10 along the axial direction of the axle body P10 and is inserted into the axle insertion portion 320 of the plate 301, and an engaged portion P12 that extends outward from the tip of the guided axle portion P11 along the axial direction and engages with the movement restricting portion 340 from below.

The shaft body P10 is cylindrical, but both end faces of the guided shaft P11 (both end faces in the horizontal direction perpendicular to the vertical direction and the axial direction) are flat to match the shape of the shaft insertion portion 320, and the bottom surface of the engaged portion P12 is a flat surface with which the return portion 3401a can engage from below. When the rotating shaft P1 is viewed from the axial direction, the engaged portion P12 is formed in a semicircular shape, but it may have a shape other than a semicircular shape as long as the return portion 3401a of the engaging claw portion 3401 can engage with it.

The guided shaft portion P11 and the engaged portion P12 may be formed only at one end or the other end of the shaft body portion P10, or may be formed at both one end and the other end of the shaft body portion P10.

When the exterior part 30 is in an upright position, the rotational connection part 3400 is disposed above the rotational axis P1, and the pair of engagement claw parts 3401 are disposed on both sides of the rotational axis P1 (at positions spaced apart on the left and right sides). The return parts 3401a of each engagement claw part 3401 are also disposed on both sides of the rotational axis P1. In this case, even when the position of the wheel 31 relative to the exterior part 30 changes from the upper side to the lower side, it remains out of contact with the rotational axis P1, so the wheel 31 is in a state in which its position can be changed. In other words, the rotation of the wheel 31 can be restricted by the locking mechanism 32.

When the exterior part 30 changes from an upright state to an inclined state, the rotation axis P1 moves laterally together with the exterior part 30. At this time, the connecting shaft 341 and the movement restricting part 340 also move laterally, but because the pair of engaging claw parts 3401 maintain a hanging position, the movement restricting part 340 becomes rotated relative to the rotation axis P1, and the engaging claw part 3401 wraps around to the underside of the engaged part P12.

In this case, even if the position of the wheel 31 relative to the exterior part 30 is to be changed from the upper side to the lower side, the wheel 31 is held to the exterior part 30 by the switching restriction means 34, so that the position of the wheel 31 relative to the exterior part 30 cannot be changed from the upper side to the lower side. This makes it impossible for the locking mechanism 32 to restrict the rotation of the wheel 31.

The configuration of the sling 1 according to this embodiment is as described above. Next, we will explain how to use the sling 1.

When lifting an object O using the lifting device 1, the chain 2 is hung on the outer circumferential side of the wheel 31, and both ends are connected to the object O.

Because the wheel 31 receives a braking force from the brake mechanism 33, even if the length from the position where the chain 2 is hooked on the wheel 31 to one end (hereinafter referred to as the length of one end) and the length from the position where the chain 2 is hooked on the wheel 31 to the other end (hereinafter referred to as the length of the other end) are unequal as shown in FIG. 1, the wheel 31 does not rotate and this state can be maintained. Therefore, the length of one end of the chain 2 and the length of the other end can be roughly adjusted according to the position of the center of gravity of the suspended object O.

Then, hang the hanging part 300 on the hoisting machine and adjust the position of the hoisting device main body part 3.

Before the sling body 3 is lifted, the wheel 31 is not subjected to a load greater than the biasing force of the biasing means 321. Therefore, the wheel 31 is in a state in which it is pulled upward relative to the exterior part 30 by the biasing force of the biasing means 321 (see FIG. 6(a)). At this time, the teeth 3230 of the exterior side meshing part 323 and the teeth 3220 of the wheel side meshing part 322 are separated from each other, so the wheel 31 is subjected to a braking force from the brake mechanism 33 but is still able to rotate.

When adjusting the position of the hoisting device main body 3, the wheel 31 is rotated while the hoisting device main body 3 is moved to one end or the other end of the chain 2. For example, the position of the hoisting device main body 3 may be set to match the center of gravity G of the object to be lifted O as shown in Figures 8 and 9, but it may also be set to a position offset from the center of gravity G of the object to be lifted. In this case, the adjustment operation unit 3311 is operated as a lever to weaken the braking force applied to the wheel 31 by the brake mechanism 33, allowing the hoisting device main body 3 to be moved easily.

In addition, the brake mechanism 33 of this embodiment can adjust the pressing force of the brake shoe 330 against the wheel 31 by the adjustment means 331, so as long as a braking force against the rotation of the wheel 31 is generated within the range in which the wheel 31 can rotate, the wheel 31 can be prevented from rotating too much. In this way, by preventing unnecessary rotation of the wheel 31, it is possible to easily adjust the position of the sling main body 3.

Then, the lifting device main body 3 is lifted by the lifting machine. If the position of the center of gravity G of the object to be lifted O deviates from the lifting center line CL (a virtual line that passes through the position where the lifting device main body 3 is lifted) when the lifting device starts to lift the lifting device main body 3, the position of the lifting device main body 3 can be moved to one end or the other end of the chain 2 by pulling the lifting device main body 3 toward one end or the other end of the chain 2 with a force greater than the braking force of the brake mechanism 33, as the wheel 31 rotates. Therefore, the position of the lifting device main body 3 is automatically adjusted so that the position of the center of gravity G of the object to be lifted O overlaps with the lifting center line CL when the lifting device main body 3 is lifted.

Furthermore, when the position of the wheel 31 relative to the exterior part 30 is changed from the upper side to the lower side, and the teeth 3220 of the wheel side meshing part 322 mesh with the teeth 3230 of the exterior side meshing part 323, the rotation of the wheel 31 is completely restricted.

As described above, with the sling 1 according to this embodiment, the rotation of the wheel 31 can be braked by increasing the pressing force of the brake shoe 330 against the wheel 31 using the adjustment means 331, so that the wheel 31 can be prevented from rotating at an unintended timing, thereby improving ease of use.

Furthermore, in the sling 1 of this embodiment, the tooth portion 3220 of the wheel side meshing portion 322 is formed on the outer periphery of the wheel side meshing portion 322, which is formed with an outer diameter larger than that of the wheel 31, so that the load on the tooth portion 3220 is reduced. Also, since the load on the tooth portion 3220 is reduced, it is possible to reduce the size of the tooth portion 3220 and increase the number of tooth portions 3220.

In addition, in the sling 1 of this embodiment, the fitting groove 310 into which the chain 2 fits and the brake abutment portion 311 against which the brake shoe 330 abuts are formed integrally, so that the simple structure can perform the function of making the wheel 31 less likely to rotate.

In addition, the brake mechanism 33 has an adjustment means 331 that adjusts the braking force applied to the rotation of the wheel 31, which is configured as a lever. This allows the operator to check the strength of the braking force that the brake mechanism 33 is applying to the rotation of the wheel 31 by looking at the direction of the lever, thereby improving ease of use.

In the lifting device 1 of this embodiment, when the exterior part 30 is pulled diagonally upward by the lifting machine (when the exterior part 30 is in a so-called diagonal pulled state), the switch restriction means 34 is unable to restrict the rotation of the wheel 31 with the locking mechanism 32. Therefore, by leaving the wheel 31 in a rotatable state, it is possible to prevent the object to be lifted O from being lifted while being subjected to a lateral force, and this also makes it possible to lift the object to be lifted O safely.

The sling device according to the present invention is not limited to the above embodiment, and various modifications can be made without departing from the spirit of the present invention.

Although not specifically mentioned in the above embodiment, the wheel side meshing portion 322 and the exterior side meshing portion 323 may be disposed only on the front side or the rear side of the wheel 31, or may be disposed on both the front side and the rear side of the wheel 31.

In the above embodiment, the biasing means 321 is configured to push up the rotation axis P1 from below, but is not limited to this configuration. For example, the biasing means 321 may be configured to pull up the rotation axis P1 from above.

Although not specifically mentioned in the above embodiment, the strength can be increased by increasing the tooth width of both the tooth portion 3220 of the wheel side meshing portion 322 and the tooth portion 3230 of the exterior side meshing portion 323. It is also possible to install the wheel side meshing portion 322 and the exterior side meshing portion 323 on one side and the other side of the wheel 31, respectively, so that the wheel 31 is supported on both sides.

In the above embodiment, the biasing means 321 is configured as a torsion spring, but is not limited to this configuration. For example, the biasing means 321 may be configured as a leaf spring, a spring spring, or a tension coil spring.

Also, the biasing means 321 may be configured with a compression coil spring as shown in FIG. 11. In this case, the locking mechanism 32 may be configured to have a push-up portion 324 that receives the biasing force of the biasing means 321 and pushes up the rotation shaft P1 (specifically, the engaged portion P12 of the rotation shaft P1), and an adjustment mechanism 325 that adjusts the compression force of the biasing means 321.

As shown in FIG. 12, the push-up portion 324 has an abutment head 3240 that abuts against the underside of the engaged portion P12 of the rotation shaft P1, a first extension shaft 3241 that extends downward from the abutment head, and a second extension shaft 3241 that extends downward from the tip of the first extension shaft 3241.

The upper surface of the abutting head 3240 abuts against the lower surface of the engaged portion P12 of the rotation shaft P1 as described above, and the lower surface of the abutting head 3240 abuts against the biasing means 321.

The first extension shaft 3241 has a smaller diameter than the abutment head 3240, and the second extension shaft 3242 has a smaller diameter than the first extension shaft 3241. In addition, the first extension shaft 3241 and the second extension shaft 3242 are inserted into the inside of the biasing means 321.

The adjustment mechanism 325 has a base part 3250 fixed to the exterior part, a movable part 3251 attached to the base part 3250 so as to be movable up and down, and a lower support part 3252 that receives the lower end of the biasing means 321 and is configured to move up and down together with the movable part 3251.

The movable part 3251 shown in FIG. 12 is formed in a bolt shape and is screwed into the base part 3250. More specifically, the movable part 3251 has a screw thread formed on its outer circumferential surface and has a movable shaft part 3251a that can be screwed into a screw hole formed in the base part 3250, and a movable head part 3251b that is connected to one end (lower end) in the axial direction of the movable shaft part 3251a.

The movable part 3251 shown in FIG. 12 is formed in a bolt shape and is screwed into the base part 3250. More specifically, the movable part 3251 has a screw thread formed on its outer circumferential surface and has a movable shaft part 3251a that can be screwed into a screw hole formed in the base part 3250, and a movable head part 3251b that is connected to one end (lower end) in the axial direction of the movable shaft part 3251a.

The movable shaft portion 3251a has an insertion recess 3251c that opens at the other end (upper end) in the axial direction, and the insertion recess 3251c is formed so that the second extension shaft 2342 can slide in the up and down direction.

The lower support 3252 is annular and is placed on the tip of the movable shaft 3251a, with the second extension shaft 3242 inserted through its center.

The locking mechanism 32 configured in this way can change the amount of compression of the biasing means 321 by adjusting the vertical position of the movable shaft portion 3251a, thereby making it possible to adjust the force pushing up the rotation axis P1.

In the above embodiment, the wheel-side meshing portion 322 has a spur gear shape, but it may have a shape other than a spur gear shape.

In the above embodiment, the wheel side meshing portion 322 is formed in a disk shape, and the teeth 3220 are formed around the entire outer periphery, but this configuration is not limited to this. For example, the wheel side meshing portion 322 may be formed in a ring shape, and the teeth 3220 may be formed around the entire inner periphery. However, when the wheel side meshing portion 322 is formed in a disk shape and the teeth 3220 are formed on the outer periphery, it is easier to increase the outer diameter of the wheel side meshing portion 322, making it easier to reduce the size of the teeth 3220, and it is also easier to increase the number of teeth 3220, so the load (burden) on the teeth 3220 of the wheel side meshing portion 322 can be reduced.

1... hoist, 2... chain, 3... hoist main body, 20... connecting means, 30... exterior, 31... wheel, 32... locking mechanism, 33... brake mechanism, 34... switching restriction means, 300... hooked portion, 301... plate, 302... roller shaft, 310... engagement groove, 311... brake contact portion, 320... shaft insertion portion, 321... biasing means, 322... meshing portion, 322... wheel Side meshing part, 323... exterior side meshing part, 330... brake shoe, 331... adjustment means, 340... movement restriction part, 341... connecting shaft, 3220... teeth part, 3230... teeth part, 3310... push operation part, 3311... adjustment operation part, 3400... rotation connection part, 3401... engagement claw part, 3401a... return part, P1... rotation shaft, P10... shaft main body part, P11... guided shaft part, P12... engaged part

Claims (3)

A long chain that is connected to an object to be lifted;
A hoisting tool main body that suspends an object to be hoisted via the chain,
the hoisting device main body has an exterior part including a hook part to be hung on a hoisting machine, a wheel rotatably attached to the exterior part, the wheel having an engagement part formed on an outer circumferential side surface to engage with the chain, a locking mechanism switchable between a state in which the rotation of the wheel is restricted and a state in which the restriction on the rotation of the wheel is released, and a brake mechanism that brakes the rotation of the wheel;
The wheel is movable up and down relative to the exterior part,
the locking mechanism includes a biasing means for biasing the wheel upward while allowing the wheel to move up and down, and a pair of meshing portions disposed opposite each other in the vertical direction, the pair of meshing portions moving toward and away from each other as the wheel is moved up and down relative to the exterior portion,
One of the pair of meshing portions is fixed to the wheel,
The other of the pair of meshing portions is fixed to the exterior portion,
The brake mechanism includes a brake shoe that presses against the wheel, and an adjustment means that adjusts the pressing force of the brake shoe against the wheel,
The wheel has an outer circumferential side surface formed with a fitting groove into which the chain fits and a brake abutment portion with which the brake shoe abuts ,
The brake abutment portion is formed at the bottom of the fitting groove.
Hanging device. The adjustment means has a lever exposed to the outside of the exterior part ,
The lever is configured to change its position in response to a pressing force of the brake shoe against the wheel.
The sling of claim 1 . The hoist body has a switching restriction means for restricting switching of the locking mechanism to a state in which rotation of the wheel is restricted,
The switching restriction means is provided on the exterior portion and is configured to directly or indirectly hold the wheel from below when the exterior portion is inclined toward one end side or the other end side of the chain.
The sling of claim 1 .