JPH10157986A - Drive mechanism for chain lever hoist - Google Patents

Abstract

PROBLEM TO BE SOLVED: To attain miniaturization and lightening of weight of a total unit. SOLUTION: An operating lever 13 is mounted in a shaft end of a drive shaft 11, in a drive member 12, a flange part 12d formed with recessed parts 12c, 12c... is protruded between the operating lever 13 and a cover 17d. The operating lever 13 eliminates necessity for penetrating the drive member 12, and front parts of a stopper plate 11d and the drive member 12 as well as a shaft end part of the drive shaft 11 can be covered.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a drive mechanism for a chain lever hoist used for lifting a heavy object or tightening a load during transportation of a load.

[0002]

2. Description of the Related Art A small chain lever hoist having a rated load of about 1 ton or less incorporates a drive mechanism including a drive shaft 1, a drive member 2, an operation lever 3, a disk 4, and a ratchet wheel 5 (FIG. 5). .

[0003] At one end of the drive shaft 1 is formed a chain wheel 6a around which the chain 6 is wound.
Protrudes from the front surface of a frame body 7 that rotatably supports the frame member 7. The drive member 2 is screwed to the drive shaft 1 via a right-hand screw 1a.
, And is rotatably attached to the outer periphery of the driving member 2. However, a switching claw 3c is incorporated into the base of the operation lever 3 via a shaft 3b. It can be switched and engaged. That is, the switching claw 3c can be switched and held between the winding position, the neutral position, and the lowering position via the leaf spring 3d.

[0004] The disk 4 is fitted to the drive shaft 1 via a serration 1b, and the ratchet wheel 5 is
The disk 4 is relatively rotatably fitted to the small diameter portion. The ratchet wheel 5 is sandwiched between the drive member 2 and the disk 4 via brake pads 5a, 5a on both sides. In addition, the ratchet wheel 5 has
The ratchet pawl 5b that prevents rotation in the lowering direction is engaged, and the ratchet pawl 5b is urged to the engaged position via a torsion spring 5c. On the other hand, a compression spring 5d is interposed between the driving member 2 and the disk 4.

[0005] A stopper plate 1d is mounted on the tip of the drive shaft 1 via a serration 1c. The stopper plate 1d is engaged with the protruding portion 2b of the drive member 2 so that the drive member with respect to the drive shaft 1 is driven. The relative rotation of 2 is 1
It can be limited to less than rotation. The operation lever 3
Are formed on the outer periphery of the drive member 2 which protrudes outwardly of the drive member 2.

[0006] A load (not shown) is connected to the tip of the chain 6, and the switching pawl 3c is switched to the winding position to switch the operation lever 3
Is reciprocated around the drive member 2, the operation lever 3 can rotate the drive member 2 in the winding direction with respect to the drive shaft 1 via the switching claws 3c, the claws 2a, 2a,. Then, the driving member 2 at this time moves forward toward the disk 4 along the right-hand screw 1a, and the brake pad 5
a, the ratchet wheel 5 is restrained so as not to rotate through 5a, so that if the operating lever 3 is further reciprocated,
The driving force of the operation lever 3 is transmitted to the chain wheel 6 a via the driving member 2, the ratchet wheel 5, the disk 4 and the driving shaft 1, and the load can be lifted via the chain 6. This is because the ratchet wheel 5 is prevented from rotating in the lowering direction via the ratchet pawl 5b, and can prevent the load from dropping.

When the switching lever 3c is switched to the lowering position and the operation lever 3 is reciprocated right and left, the driving member 2
Recedes away from the disk 4. Then, the brake pads 5a, 5a are loosened, and the disc 4, the drive shaft 1
Becomes rotatable relative to the ratchet wheel 5,
Although the load decreases, the rotation of the drive shaft 1 at this time acts to relatively advance the drive member 2. That is, the driving member 2 re-restrains the ratchet wheel 5 by the load drop, and the disk 4, the brake pad 5
a, 5a, the load can be stopped again via the ratchet wheel 5. Therefore, the load at this time is
The drive member 2 can be safely lowered in accordance with the amount of rotation of the drive member 2 in the lowering direction by the operation lever 3.

On the other hand, when the switching claw 3c is switched to the neutral position, the operation lever 3 is free from the drive member 2. Therefore, when no load is connected to the chain 6, the driving member 2
Is rotated by a finger, the extension length of the chain 6 from the chain wheel 6a can be freely adjusted. That is, if the driving member 2 is rotated in the hoisting direction, the chain wheel 6a can be rotated in the hoisting direction via the brake pads 5a, 5a, the ratchet wheel 5, the disk 4, and the drive shaft 1, and the driving member 2 By rotating in the lowering direction, the chain wheel 6a can be rotated in the lowering direction via the drive shaft 1 by engaging the protrusion 2b with the stopper plate 1d. However, when rotating the driving member 2 in the lowering direction, when the ratchet wheel 5 is restrained, the ratchet pawl 5 is opposed to the spring 5c.
The engagement between the b and the ratchet wheel 5 may be temporarily released. The ratchet wheel 5 can also be released by switching the switching claw 3c in the lowering direction to fix the operation lever 3 and pulling the chain 6 lightly and shockfully in the lowering direction.

When adjusting the extension length of the chain 6, the compression spring 5d causes the driving member 12 to rotate with respect to the driving shaft 11 due to vibration or the like, and the ratchet wheel 5 is inadvertently restrained. To prevent

[0010]

According to the prior art, the driving member penetrating the base of the operating lever back and forth needs to apply a necessary and sufficient rotational torque by a finger when adjusting the extension length of the chain. In addition, there is a problem that an outer diameter of several tens of mm or more is required at a minimum, and the base of the operation lever must be larger than that, which limits the reduction in size and weight of the entire system. If the diameter of the driving member penetrating the base of the operating lever is reduced and a ring member for rotating operation is attached to the tip of the driving member protruding outside the operating lever, the driving member becomes a combination of a plurality of parts. Inevitably, the cost increases.

Accordingly, an object of the present invention is to reduce the size and weight easily by projecting the flange portion at the intermediate portion of the drive member inside the operation lever in view of the problems of the prior art. An object of the present invention is to provide a drive mechanism for a chain lever hoist.

[0012]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a drive shaft, a drive member screw-connected to the drive shaft via a right-hand screw, and a disk rotating integrally with the drive shaft. A ratchet wheel sandwiched between the drive member and the disc via brake pads on both sides, and the drive member is wound in the winding direction and winding direction via an operation lever rotatably mounted on the shaft end of the drive shaft. The gist of the present invention is to switch to the lowering direction and drive the rotation, and to project a flange portion between the operation lever and a cover that stores the ratchet wheel.

The driving member can be provided with a non-slip recess in the flange portion.

Further, the drive member limits the relative rotation with respect to the drive shaft via a stopper plate, and the stopper plate can be mounted on the shaft end of the drive shaft and covered by the operation lever.

[0015]

According to the structure of the invention, the operation lever is rotatably mounted on the shaft end of the drive shaft, and the drive member has a flange portion between the operation lever and the cover inside the operation lever. It is protruding. Therefore, the driving member only needs to have a necessary and sufficient diameter for only the flange portion protruding to the outside, and it is not necessary to increase the diameter of the whole, and the base of the operation lever does not need to penetrate the driving member. Since only the shaft end portion of the shaft needs to be penetrated, the shaft can be formed sufficiently small.

If a non-slip concave portion is formed in the flange portion of the driving member, the finger can be hung on the concave portion when the driving member is rotated by the finger, and the operability can be improved.

When the stopper plate is covered by the operation lever, the stopper plate is not exposed to the outside.
The external design can be improved, and the operation lever can more reliably protect the right-hand screw formed on the drive shaft and the serration at the shaft end.

[0018]

Embodiments of the present invention will be described below with reference to the drawings.

The drive mechanism of the chain lever hoist includes a drive shaft 11, a drive member 12, an operation lever 13, and a disk 1.
4. The ratchet wheel 15 is used as a main member (FIG. 1). The drive shaft 11 is integrally formed with a chain wheel 16a around which the chain 16 is wound.
It is rotatably supported by the frame 17.

The frame 17 is a double screw type bolt 17a, 1
A pair of front and rear frame plates 17c, 17c is assembled in parallel via 7a, 17b (FIGS. 1, 2). However, the upper and lower bolts 17a, 17a are stepped bolts which also serve as spacers, and each of them has a spring washer 17a.
a2, 17a2, nuts 17a1, 17a1, front and rear frame plates 17c, 17c, front and rear covers 17d, 17d
Together.

The bolt 17b is a multi-stepped bolt that penetrates the frame plates 17c, 17c.
The spacer collar 17b3 is mounted between the positions c. The nut 17b1 and the spring washer 17b2 on the back side of the bolt 17b fasten the cover 17d on the back side together. doing. At the upper part of the frame 17, a top hook 17e with a stopper 17e1 is attached. At the lower part of the frame 17, a chain guide 17f for guiding the chain 16 is provided.
Is attached.

The chain 16 wound around the chain wheel 16a is
A hook 16b with a stopper 16b1 is attached to one end of the lower bolt 17a for connection of a load (not shown).

The drive shaft 11 is connected to the frame 1 via a chain wheel 16a.
7 protrudes from the front. The drive shaft 11 is provided with a serration 11b at the base and a serration 11c at the tip in addition to the right-hand thread 11a at the middle. Also, drive shaft 1
A stopper plate 11d is attached to the distal end portion 1 via a serration 11c (FIGS. 1 and 3).

The drive member 12 is screwed to the drive shaft 11 via a right-hand screw 11a. The drive member 12 has claws 12a, 12a,... Formed on the outer periphery of a small diameter portion in front, and a short arc-shaped protrusion 12b that is engaged with the stopper plate 11d protrudes from the front end face. The rear large-diameter portion is formed in a cylindrical shape, and a flange portion 12d is formed on the outer periphery of the intermediate portion. Non-slip concave portions 12c are formed on the peripheral surface of the flange portion 12d. (FIGS. 1 and 2). The concave portions 12c may be formed in a knurled shape.

The operating lever 13 is rotatably mounted on the shaft end of the drive shaft 11 via a washer 11e1, a spring washer 11e2, and a nut 11e3. The operation lever 13 covers the stopper plate 11d and the front part of the drive member 12, and the flange 12d of the drive member 12 projects between the operation lever 13 and the front cover 17d. A grip 13e is formed at the tip of the operation lever 13, and a switching claw 13c is attached to the base via a shaft 13b (FIGS. 1 and 3).

The switching claw 13c is formed with projections 13c1, 13c1 which are engaged with the claws 12a, 12a... Of the small diameter portion of the driving member 12 from the left and right directions.
An angled projection 13c2 is formed. Switching claw 1
Behind 3c, a leaf spring 13d is disposed via fixing pins 13d1 and 13d1, and the leaf spring 13d engages the projection 13c2 to raise the switching claw 13c to the winding position (two points in FIG. 3). (A chain line), a neutral position (solid line in the figure), and a lowering position (not shown). The left and right ends of the switching claw 13c are provided with openings 13f.
And protrudes to both sides of the operation lever 13 (FIG. 2,
A name plate 13g indicating the switching position of the switching claw 13c is screwed to the outer surface of the operation lever 13 (FIG. 1, FIG. 3).
(Fig. 2).

When the operating lever 13 is reciprocated right and left around the drive shaft 11 and the drive member 12 (in the direction of arrow K1 in FIG. 2), the switching claw 13c is switched to the winding position, whereby the drive member 12 is moved. It can be driven to rotate in the hoisting direction (direction of arrow K2 in FIG. 3), and can be driven to rotate in the lowering direction (direction of arrow K3 in FIG. 3) by switching the switching claw 13c to the lowering position. Also,
By switching the switching claw 13c to the neutral position, the operation lever 13 can be separated from the drive member 12.

The disk 14 is mounted on the base of the drive shaft 11 via a serration 11b (FIG. 1). The disk 14 has a flange-shaped large-diameter portion formed at the rear portion, and a small-diameter portion formed at the front portion that can enter the rear large-diameter portion of the drive member 12. The disk 14 can rotate integrally with the drive shaft 11 via the serrations 11b.

The ratchet wheel 15, together with the brake pads 15a on both sides, is fitted to the small diameter portion of the disk 14 so as to be relatively rotatable (FIGS. 1 and 4). When the driving member 12 advances toward the disk 14 along the right-hand screw 11a, the ratchet wheel 15
The disc 14, via the brake pads 15a, 15a,
The driving member 12 is held between the driving members 12.
Can be integrally restrained together with the brake pads 15a, 15a, the ratchet wheel 15, and the disk 14.

The ratchet wheel 15 is prevented from rotating in the lowering direction via a ratchet claw 15b. That is, the ratchet claw 15b is
1 and is swingably attached to the tip end of the bolt 17b via a torsion spring 15c, and is urged to a meshing position with the ratchet wheel 15 via a torsion spring 15c. One end of the torsion spring 15c is engaged with the ratchet pawl 15b, and the other end is engaged with the hole 17c1 of the frame plate 17c. Further, the ratchet pawl 15b protrudes outside through the opening 17d1 of the cover 17d (FIGS. 1 and 2). (The two-dot chain line in FIG. 4).

A compression spring 15d is interposed between the drive member 12 and the disk 14 (FIG. 1).

The drive mechanism of the chain lever hoist can operate in exactly the same manner as the drive mechanism shown in FIG. The symbols 11, 12,... In FIGS. 1 to 4 correspond to the symbols 1, 2,.

The distal end of the drive shaft 11 including the stopper plate 11d is almost completely covered by the operation lever 13, and the ratchet wheel 15 includes the brake pads 15a, 15a, the ratchet pawl 15b, the disk 14
At the same time, it is stored in the front cover 17d. When adjusting the extension length of the chain 16 from the chain wheel 16a, the operation lever 13 and the front cover 17d are adjusted.
The flange 12d of the driving member 12 protruding between them may be grasped by fingers and the driving member 12 may be rotated.

In the above description, the chain wheel 16a may be connected to the drive shaft 11 via a speed reduction mechanism (not shown) incorporated in the frame 17 instead of being formed integrally with the drive shaft 11. However, at this time, the drive shaft 11 is rotatably supported by the frame 17 separately from the chain wheel 16a.

[0035]

As described above, according to the present invention, the operation lever does not have to penetrate the drive member back and forth by projecting the flange portion of the drive member to the outside inside the operation lever. Because the shaft end of the drive shaft can be covered, the size of the base of the operation lever can be minimized to minimize the overall size and weight, and the overall design can be neatly organized. effective.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of the entire configuration.

FIG. 2 is an overall perspective explanatory view.

FIG. 3 is a sectional view taken along line XX of FIG. 1;

FIG. 4 is a sectional view taken along the line YY of FIG. 1;

FIG. 5 is a diagram corresponding to FIG. 1 showing a conventional example.

[Explanation of symbols]

 1, 11: drive shaft 1a, 11a: right-hand screw 1d, 11d: stopper plate 2, 12 ... drive member 2c, 12c ... concave portion 12d: flange portion 3, 13 ... operating lever 4, 14 ... disk 5, 15 ... ratchet wheel 5a, 15a ... brake pad

Claims (3)

[Claims] 1. A drive shaft, a drive member screwed to the drive shaft via a right-hand screw, a disk rotating integrally with the drive shaft, and a drive member and the disk connected via brake pads on both sides. And a ratchet wheel interposed therebetween. The driving member is rotatably driven by switching between a hoisting direction and a lowering direction via an operating lever rotatably mounted on the shaft end of the drive shaft. A drive mechanism for a chain lever hoist, characterized in that a flange portion is projected between a lever and a cover that stores the ratchet wheel. 2. The drive mechanism for a chain lever hoist according to claim 1, wherein the drive member has a non-slip recess formed in the flange portion. 3. The driving member restricts relative rotation with respect to the driving shaft via a stopper plate, and the stopper plate is mounted on a shaft end of the driving shaft and is covered by the operation lever. A drive mechanism for a chain lever hoist according to claim 1 or 2.