JP2000226190A - Lever hoist - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance safety by preventing a shaft for a claw from inclination even under a heavy load and to reduce costs by eliminating necessity for thickening the shaft diameter of the shaft for the claw. SOLUTION: This lever hoist 1 turns and moves a pressing driving member 13 by reciprocation exerted by an operating handle 14 and presses and rotates a pressure member 12 fixed to a driving shaft 9 through a ratchet gear 16 and a pair of friction members 15, 15. Where a ratchet claw 17 for rotating the ratchet gear 16 only in the hoisting direction is provided by holding the ratchet gear 16 on the shaft 18 for a claw of a side plate 3. Each member located from the pressing driving member to the pressure member is covered brake covers 31 (31a-31d) fixed to the side plate, and the handle covers 14a, 14b of the operating handle. The extreme head part 18a of the shaft for the claw is held on a recessed part 31e formed in the brake covers.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lever hoist for lifting, lowering or towing a load by reciprocating a lever.

[0002]

2. Description of the Related Art FIG. 4 is a longitudinal sectional view showing a main part of a lever hoist of a conventional structure, which is connected to a drive shaft c via a ratchet gear a and a pair of friction members b, b arranged on both surfaces thereof. A hoist having a configuration in which a fixed pressure receiving member d is pressed and rotated by a pressing drive member e is shown. As shown in this figure, the ratchet pawl f engaged with the ratchet gear a
Is held by a claw shaft i of a side plate h that holds a drive shaft c and a load sheave g, and is engaged with locking teeth of a ratchet gear a so as to rotate the ratchet gear a only in the winding direction. I have. The brake units such as the pressure receiving member d and the pressing drive member e are provided to prevent ingress of rainwater and the like.
It is covered with a brake cover j fixed to the side plate h and a handle cover k of an operation handle.

[0003]

However, in the lever hoist having the above-mentioned structure, the claw shaft for holding the ratchet claw has a heavy load since the base end is merely held by the side plate. In this case, excessive force is applied to each ratchet claw, and the claw shaft and side plate supporting the ratchet claw are deformed, and the engagement of the claw is reduced, and the engagement with the ratchet gear may be released (see FIG. 4 two-dot chain line). Therefore, in the conventional lever hoist, the diameter of the claw shaft is increased to avoid the above-mentioned inconvenience.

The present invention has been made in view of these circumstances, and a main object of the invention is to prevent the nail shaft from being bent outward even under a heavy load, to further improve safety and Another object of the present invention is to provide a lever hoist which can reduce the cost by eliminating the need to increase the diameter of the claw shaft.

[0005]

SUMMARY OF THE INVENTION According to the present invention, a pressing drive member screwed on a drive shaft so as to be able to advance and retreat is rotated by reciprocating an operation handle, and a ratchet gear and a pair of gears disposed on both surfaces thereof are provided. The present invention is applied to a lever hoist which presses and rotates a pressure receiving member fixed to a drive shaft via the friction member.

In order to achieve the above object, a lever hoist according to the present invention has a ratchet pawl for rotating a ratchet gear only in a hoisting direction on a side plate for holding a drive shaft and a load sheave. Each member from the pressing drive member to the pressure receiving member is covered by a brake cover fixed to the side plate or a handle cover of an operation handle, and a tip end head of the claw shaft is attached to the brake cover. It is characterized by being held in the formed recess.

Preferably, in addition to the above configuration, the brake cover is fixed by stay bolts for fixing two side plates holding a drive shaft and a load sheave, and the ratchet pawl is provided with a ratchet gear. A lever hoist, which is provided diametrically opposed to each other, and wherein the tip heads of the pawl shafts for holding the ratchet pawls are respectively held in recesses formed in the brake cover. is there.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the lever hoist 1 of the present invention will be described in more detail. FIG. 1 is a side view showing one embodiment of the lever hoist 1 of the present invention, and FIG. 2 is a longitudinal sectional view showing the internal structure of the lever hoist 1. FIG. 3 is a front view showing only the lower half of the lever hoist 1. The lever hoist 1 includes a load sheave 4 between a pair of side plates 2 and 3 held in parallel. The load sheave 4 is rotatably held between the side plates 2 and 3 by bearings 5 and 5. . An upper hook 6 is provided at an upper portion between the two side plates 2 and 3, while a load chain 7 wound around the load sheave 4 is provided.
A lower hook 8 for hanging a luggage is connected to a lower end of the vehicle.

A drive shaft 9 is rotatably inserted into the center of the load sheave 4, and both ends of the drive shaft 9 are connected to the load sheave 4.
Protruding from both the left and right ends. In FIG. 2, a pinion gear G ₁ is fixed to a left protrusion of the drive shaft 9, and a first screw portion 9 a, a spline portion 9 b, and a Two screw portions 9c are formed in order. The pinion gear G ₁ of the drive shaft 9 is connected to the load sheave 4 via a reduction gear transmission system G ₂ , G ₃ , G ₄ , whereby the rotation of the drive shaft 9 is transmitted to the load sheave 4. You.

The gears G _{1 to} G ₄ are covered by a gear cover 10 attached to the left side plate 2. The gear cover 10 includes a box-shaped recess 10a opened to the right, and a flange 10b extending radially outward is continuously provided at the right end of the box-shaped recess 10a. Are superimposed on the side plate 2 and attached.
The left end wall 10 of the box-shaped recess 10a of the gear cover 10
c and the left side plate 2 hold both ends of the gears G ₂ , G ₃ via bearings 11, 11.

A pressure receiving member 12 and a pressing drive member 13 are screwed into the first screw portion 9a of the drive shaft 9 from the side closer to the side plate 3. The pressure receiving member 12 is fixed to the drive shaft 9 by being screwed to the innermost part of the first screw portion 9a. On the other hand, the pressing drive member 13 is provided so as to be screwed forward and backward on the drive shaft 9, and is configured to be rotated by the operation handle 14 as necessary. The pressure receiving member 12 has a disk portion 12a and a boss portion 12b. A ratchet gear 16 is externally fitted to the boss portion 12b disposed on the right side by being sandwiched between a pair of friction members 15, 15. I have.

The ratchet gear 16 is provided at its outer periphery with locking teeth 16a which are inclined to one side in the circumferential direction (FIG. 1). The ratchet gear 16 and the friction members 15 disposed on both sides thereof can be pressed by the pressing drive member 13 against the disk portion 12a of the pressure receiving member 12. The right side plate 3 is provided with a ratchet pawl 17 which is engaged with the locking teeth 16a so as to rotate the ratchet gear 16 only in the winding direction. In this embodiment, two ratchet pawls 17 are provided at positions diametrically opposed to the ratchet gear 16. Each ratchet pawl 17, 17
Are respectively pivotally supported and held by claw shafts 18, 18 protruding rightward from the right side plate 3 and provided in parallel.

Each ratchet pawl 1 held on the pawl shaft 17
The lower end of the ratchet gear 16 is engaged with a locking tooth 16 a on the outer peripheral portion of the ratchet gear 16, and is driven downward by the urging force of a coil spring 19 which is disposed so as to be fitted on the claw shaft 18. While the ratchet gear 16 rotates in the hoisting direction, the ratchet gear 16 can rotate while bouncing off the ratchet pawl 17. Thus, the ratchet pawl 17 is connected to the load sheave 4
Ratchet gear 1 so that it can rotate only in the hoisting direction of
6 is locked.

In the example shown in the figure, the pressing drive member 13 screwed to the first screw portion 9a so as to be able to advance and retreat is formed separately into a main body 13-1 and a pressing plate 13-2. -1 and the pressing plate 13-2 are engaged with each other, so that both members 1
3-1 and 13-2 are configured to rotate integrally.
The main body 13-1 and the pressing plate 13-2 may be formed integrally.

Between the pressure receiving member 12 and the pressing drive member 13, a left-handed coil spring 20 whose both ends are engaged with the two members 12, 13 is loosely fitted to the drive shaft 9 and arranged. The pressing drive member 13 is urged to rotate in the lowering direction. The coil spring 13 is used for the load sheave 4
When the pressing drive member 13 is to be hoisted in a state where a load is applied, a spring having a spring force that can be sufficiently lightly used is used. The coil spring 20 has a left end inserted into a boss hole 12 c formed in the boss 12 b of the pressure receiving member 12, and a right end inserted into the pressing plate 1 of the pressing drive member 13.
3-2, it is inserted and arranged in a spring arrangement hole 13a formed in the center.

A rotation restricting member 21 is provided on the spline portion 9b of the drive shaft 9 adjacent to the pressing drive member 13 by spline coupling. The rotation restricting member 21 has a rotation restricting protrusion 21 a formed on an end face facing the pressing drive member 13. The rotation restricting protrusion 21 a contacts the pressing drive member 13, so that the pressing drive member 13 is attached to the drive shaft 9. On the other hand, the rotation of the pressing drive member 13 to the right is prevented more than necessary by preventing it from rotating more than necessary.

An operation wheel 22 is provided on the outer periphery of the rotation restricting member 21.
Are rotatably fitted to the rotation restricting member 21, and a pressing release protrusion (not shown) formed to project leftward from the left end surface of the operating wheel 22 abuts a part of the pressing driving member 13. It is possible. The operation wheel 22 is provided on the drive shaft 9.
Is attached to the second threaded portion 9c via a washer 23 via a washer 23.

An outer peripheral portion of the pressing drive member 13 is housed in an upper portion of the operation handle 14. The operation handle 14 is
It has two handle covers, an inner cover 14a and an outer cover 14b. The inner cover 14a has a tubular opening 14c surrounding the pressing plate 13-2 side of the pressing drive member 13 projecting to the left. Is formed. The outer cover 14b also has a cylindrical opening 14 inserted into an annular groove 22a formed in the left end surface of the operation wheel 22.
d is formed to protrude to the right. The inner cover 14a and the outer cover 14b are integrally connected by a plurality of bolts and nuts 25.

The operation handle 14 extends below the pressing drive member 13 and has a rotation direction switching claw 26 provided inside thereof. Rotation direction switching claw 26
Is rotatably held by the shaft 27 with respect to both handle covers 14a and 14b. The shaft 27 protrudes outside the operation handle 14, and a switching lever 28 is attached to this protruding portion. By operating the switching lever 28, the rotation direction switching claw 26 is engaged so that the pressing drive member 13 is rotated in the hoisting direction or the unwinding direction, and is also rotated in either direction. It is held in the neutral position to prevent it from occurring. A pressing member 30 urged upward by a spring 29 is in contact with the lower end of the rotation direction switching claw 26, whereby the rotation direction switching claw 26 is elastically held at a predetermined switching position. You.

The right side plate 3 has a handle cover 14
a, 14b, the ratchet pawl 26 and the pressure receiving member 12
A brake cover 31 is provided to cover the brake unit made up of each member from to the pressing drive member 13 and to prevent the brake unit from entering by rain and the like. The brake cover 31 is provided with a box-shaped recess 31a opened to the left to cover and close the brake portion from the right, and a flange 31b extending radially outward is continuously provided at the left end of the box-shaped recess 31a. The flange 31b is attached to the side plate 3 in an overlapping manner.

The gear cover 10 and the brake cover 31 are attached to the side plates 2 and 3 by stay bolts 32 for positioning and fixing the two side plates 2 and 3 at an interval.
Is preferably used (FIG. 3). That is, a flange 10b of the gear cover 10 superimposed on the left side plate 2,
The nut is passed through the stay bolt 32 between the left and right side plates 2 and 3 through the flange portion 31b of the brake cover 31 overlapped with the right side plate 3 and fastened with a nut. In this embodiment, the gear cover 10 and the brake cover 31 are fixed to each of the side plates 2 and 3 by four stay bolts 32.

At the center of the right end wall 31c of the box-shaped recess 31a of the brake cover 31, a cylindrical opening 31d is formed to protrude rightward. And the operation handle 1
Reference numeral 4 denotes a fitting in which the cylindrical opening 14c of the inner cover 14a is fitted to the cylindrical opening 31d of the brake cover 31. The positioning of the two members 31, 14 is performed by a stopper tubular member 33 fitted to the inner surface of the tubular opening 14c of the inner cover 14a. In other words, the stopper tubular member 33 is made of a tubular material having a substantially U-shaped cross section in which the right and left ends are slightly bent outward in the radial direction, and is fitted to the inner surface of the tubular opening 14c of the inner cover 14a. This restricts the movement of the operation handle 14 to the outside in the axial direction. Thereby, the operation handle 14 is reciprocally rotatable around the cylindrical opening 31 d of the brake cover 31.

On the right end wall 31c of the box-shaped concave portion 31a of the brake cover 31, a circular concave portion 31e is formed on the right side at a position diametrically opposed to the cylindrical opening 31d. The concave portion 31e is formed at a position corresponding to the two claw shafts 18 provided on the right side plate 3, and the front end portions 18a of the claw shafts 18 are fitted and held. Become. Therefore, while each claw shaft 18 has its base end held by the side plate 3, its distal head 18 a is held by the concave portion 31 e of the brake cover 31, and even when heavy load is applied, the claw shaft 18 is caught by the claw shaft 18. The shaft 18 does not tilt,
It can always be kept horizontal. As a result, the engagement between the ratchet pawl 17 and the ratchet gear 16 is always ensured, and the safety can be further improved. Further, since it is not necessary to make the pawl shaft 18 thick, the cost can be reduced. .

[0024]

As described above in detail, according to the lever hoist of the present invention, the claw shaft whose base end is held on the side plate is held with its head end in the recess of the brake cover. Therefore, even under a heavy load, the nail shaft is prevented from being bent outward to further improve safety,
It is also possible to eliminate the necessity of increasing the diameter of the claw shaft or the like, thereby reducing costs.

[Brief description of the drawings]

FIG. 1 is a side view showing an embodiment of a lever hoist according to the present invention.

FIG. 2 is a longitudinal sectional view of the lever hoist of FIG.

FIG. 3 is a front view showing only a lower half of the lever hoist of FIG. 1;

FIG. 4 is a longitudinal sectional view showing a main part of a conventional lever hoist.

[Explanation of symbols]

 Reference Signs List 1 lever hoist 2 (left) side plate 3 (right) side plate 4 load sheave 9 drive shaft 12 pressure receiving member 13 pressing drive member 14 operating handle 14a inner cover (handle cover) 14b outer cover (handle cover) 15 friction member 16 Chet gear 17 Ratchet claw 18 Claw shaft 18a Tip head 31 Brake cover 31e Recess 32 Stay bolt

Claims (2)

[Claims] A push drive member screwed on a drive shaft so as to be able to advance and retreat is rotated by reciprocation of an operation handle, and is driven via a ratchet gear and a pair of friction members arranged on both surfaces thereof. In a lever hoist that presses and rotates a pressure receiving member fixed to a shaft, a ratchet pawl that rotates a ratchet gear only in a hoisting direction is provided on a side plate that holds a drive shaft and a load sheave while being held by a pawl shaft. Each member from the pressing drive member to the pressure receiving member is covered by a brake cover fixed to a side plate or a handle cover of an operation handle, and a tip end head of the claw shaft is formed on the brake cover. A lever hoist characterized by being held in a concave portion. 2. The brake cover is fixed by stay bolts for fixing two side plates holding a drive shaft and a load sheave, and the two ratchet claws are opposed to each other in a diametrical direction of a ratchet gear. The lever hoist according to claim 1, wherein each of the ratchet pawls is provided, and a tip end head of each pawl shaft that holds each ratchet pawl is held by a recess formed in the brake cover.