JPH07309592A - Brake mechanism for hoist, etc., and chain lever hoist using the mechanism - Google Patents

Abstract

PURPOSE:To prevent the excessive increase of the operating force when the load is taken down. CONSTITUTION:A brake mechanism 30 is constituted by combining a disc 32, auxiliary cylinder 33, driving member, brake cylinder 35, brake pads 36a and 36a, and a ratchet wheel 36, for a shaft, and the auxiliary cylinder 33 is screwed on the shaft with a right screw 31b, and the brake cylinder 35 is screwed on the auxiliary cylinder 33. When the driving member is driven in the taken-down direction, the auxiliary cylinder 33 revolves integrally, and the brake cylinder 35 retreats in the axis line direction even if closely attached to the brake pad 36a, and can release the ratchet wheel 36 through the retreat in the axis line direction.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a brake mechanism such as a hoist used for cargo handling work and the like, and a chain lever hoist using the brake mechanism.

[0002]

2. Description of the Related Art A winch or hoist (hereinafter simply referred to as a hoist) is used for towing or lifting a heavy object. In addition to hoisting heavy objects, hoists etc. are not only for hoisting, but also for hoisting down safely at an appropriate speed.
Equipped with a brake mechanism.

As a brake mechanism for a hoist or the like, a shaft A is used.
A disk A1 and a feed screw A2 are formed at the shaft end of the (Fig. 8), the drive member W is screwed to the feed screw A2 consisting of a right-hand thread, and the drive member W is rotatable between the disc A1 and the drive member W. It is known that the ratchet wheel R of FIG. However, the shaft A is connected to a winding mechanism for output such as the drum D via a suitable speed reducing mechanism GB. Moreover, the ratchet wheel R has a lock claw R2.
The rotation in the lowering direction is prevented by the brake pads R1 and R1 on both sides of the ratchet wheel R.

A stopper plate P is fixed to the shaft end of the shaft A via a nut N. Stopper plate P
Is engaged with projections W1 and W1 formed on the inner peripheral surface of the driving member W by the projection P1 provided on the outer periphery of the shaft A.
The relative rotation range of the drive member W with respect to can be limited to about 1/2 rotation.

The shaft A is driven through the driving member W by attaching a suitable lever handle to the driving member W. When the driving member W rotates in the winding direction (referred to as the arrow K1 direction in FIG. 8, the same applies hereinafter) with respect to the shaft A, the driving member W is displaced to the disk A1 side via the feed screw A2, and the shaft A and the drum D are moved. And shall rotate in the same direction via the reduction gear mechanism GB.

Now, when the load L is attached to the drum D through the wire L1 and the drive member W is rotated in the winding direction,
The drive member W advances toward the disc A1 side, and the ratchet wheel R is sandwiched between the disc A1 and the drive member W via the brake pads R1 and R1. Therefore,
The shaft A can rotate integrally via the drive member W, the ratchet wheel R, and the disk A1 and can wind up the load L. At this time, the load L can be stopped at an arbitrary position by the lock claw R2. This is because the rotation direction of the shaft A due to the load L is the direction in which the drive member W is displaced to the disk A1 side by the feed screw A2.

On the other hand, to lower the load L, the drive member W is rotated in the lowering direction (referred to as the arrow K2 direction in the figure, the same applies hereinafter) without releasing the lock claw R2. At this time, the drive member W moves through the feed screw A2 to the disc A
Since the disk A1 and the ratchet wheel R are separated by retreating in the direction away from 1, the shaft A can be rotated despite the ratchet wheel R being stopped,
The load L drops.

When the driving member W is stopped while the load L is being lowered, the shaft A is driven in the lowering direction relative to the driving member W, so that the driving member W advances toward the disk A1 side. Then, the disk A1, the ratchet wheel R, and the driving member W are integrated, and the load L is also stopped. That is, the load L can be safely unwound as the driving member W rotates in the unwinding direction.

[0009]

According to the prior art, when the load is stopped, the drive member strongly clamps the brake pad and the ratchet wheel via the feed screw, so that the drive member is driven by the ratchet wheel. Since the rotation of the shaft is blocked, when lowering the load,
There is a problem that operability is not good because it is necessary to temporarily apply a large operating force in the unwinding direction. This is because the drive member must slide with respect to the brake pad in the first stage of rotation in the lowering direction.

Therefore, in view of the problems of the prior art, an object of the present invention is to make an excessive operating force when lowering a load by bringing a brake cylinder into contact with a brake pad instead of a drive member. Therefore, it is an object of the present invention to provide a brake mechanism such as a hoist that can easily realize extremely good operability, and a chain lever hoist that uses the brake mechanism.

[0011]

The structure of the first invention according to the present application for achieving the above object is a shaft for driving a winding mechanism for output through a reduction mechanism, and a disk rotating integrally with the shaft. An auxiliary cylinder screwed to the shaft through a right screw, a drive member that rotates integrally with the auxiliary cylinder, a brake cylinder screwed to the auxiliary cylinder and driven in the winding direction by the drive member, and brake pads on both sides. The gist of the present invention is to include a ratchet wheel that is sandwiched between the disc and the brake cylinder via the spring, and a spring that biases the drive member in the winding direction with respect to the brake cylinder.

The screw connecting the auxiliary cylinder and the brake cylinder with a screw can be formed with a lead smaller than the right screw.

According to a second aspect of the invention, the brake mechanism according to the first aspect of the invention, a swing lever that swings back and forth around a shaft to drive the drive member in a predetermined direction via the switching claw, and an output chain. The gist of the present invention is to include a frame for accommodating a vehicle and assembling a speed reduction mechanism, and a chain with a hook that is wound around the chain wheel.

The switching claw may be switched and fixed to a winding position, a neutral position, or a winding position via a leaf spring.

Further, the swing lever has an opening at the base for inserting the brake mechanism in the axial direction, the frame body is provided with a spacer cover for covering the brake mechanism, and the swing lever is
The top of the spacer cover can be relatively rotatably fitted in the opening with respect to the frame, and can be detachably connected via a snap ring.

[0016]

According to the structure of the first invention, the drive member rotates integrally with the auxiliary cylinder, and the auxiliary cylinder is screw-engaged with the shaft through the right-hand screw, while the brake cylinder has the drive member. When the drive member is driven in the winding direction, the brake cylinder moves forward along the axis together with the auxiliary cylinder via the right-hand screw, and the brake pad and ratchet wheel are pressed hard against the disc, and the ratchet wheel. Can be pinched so as not to rotate and restrained.
Therefore, thereafter, if the drive member is further rotated in the winding direction, the output winding mechanism can be driven through the shaft and the reduction mechanism connected to the shaft to wind up the load.

When lowering the load, the driving member is driven in the lowering direction. At this time, since the auxiliary cylinder that rotates integrally with the drive member is screwed to the shaft through the right-hand screw, the auxiliary cylinder retracts in the direction away from the ratchet wheel, and thus the brake cylinder slides on the brake pad. Without reversing, you can release the ratchet wheel. That is, the brake cylinder at this time does not need to slide with respect to the brake pad, but simply retracts, so it is not necessary to apply an excessive operating force to the drive member at the beginning of the lowering operation. Since the spring biases the drive member in the winding direction against the brake cylinder and causes one rotation to follow the other rotation, the entire operation is smooth even if some relative rotation is allowed between the two. Can be

When the screw that connects the auxiliary cylinder and the brake cylinder has a lead smaller than the right screw that connects the shaft and the auxiliary cylinder to each other, the former screw may be either a left screw or a right screw. However, if the former screw is a left-hand thread, the retreat amount of the brake cylinder is determined by the sum of the right-hand thread lead connecting the shaft and the auxiliary cylinder with the left-hand thread lead, and the former screw is the right-hand thread. In the case of 1, the amount of retreat of the brake cylinder is determined by the difference between the leads of both.

According to the structure of the second aspect of the invention, the swing lever is provided with a chain with a hook that is wound around an output chain wheel by driving the drive member of the brake mechanism in a predetermined direction via the switching claw. , Can wind up and down the load. However, at this time, the whole is to be hung at a predetermined position for use, for example, via a hook attached to the frame. In addition, the predetermined direction means one of a winding direction and a winding direction.

When the switching claw is switched and fixed via the plate spring, the number of parts is smaller than that when the switching claw is switched and fixed via a coil spring and a pressing member biased by the coil spring. It is possible to reduce. This is because when the coil spring is used, a guide cylinder for housing it and a bracket for fixing the guide cylinder are required.

If the swing lever is detachably connected to the frame body, the both can be separated as required,
It is convenient for maintenance and inspection of the brake mechanism.

[0022]

Embodiments Embodiments will be described below with reference to the drawings.

The chain lever hoist is a swing lever 1
0, the frame 20, and the brake mechanism 30 are the main members (FIGS. 1 and 2). However, the brake mechanism 30
It is assembled to the frame body 20 and is housed in the base portion of the swing lever 10.

The brake mechanism 30 comprises a shaft 31, a disk 32, an auxiliary cylinder 33, a drive member 34, a brake cylinder 35, and a ratchet wheel 36, which are integrally assembled (FIGS. 2 and 3). At one end of the shaft 31, gears 37a, 37b,
A reduction gear mechanism formed by combining 37b and 37c and an output chain wheel 38 are provided.

The shaft 31 has a serration 31a formed in the middle portion (FIGS. 3 and 4) and has a right-hand thread 31b on one side of the serration 31a. However, the right screw 31b is a trapezoidal screw having a lead of about 10 mm.

The disc 32 has serrations 32 on its inner circumference.
A boss portion 32b having a is formed in one direction and is fitted to the serration 31a of the shaft 31 so as not to rotate relative to it. Further, the brake pads 3 on both sides are attached to the boss portion 32b.
A ratchet wheel 36 is mounted together with 6a and 36a so as to be relatively rotatable. The ratchet wheel 36 is provided with a lock claw 36b, and the lock claw 3
6b is swingably attached to the small shaft 36c, and is engaged with the ratchet wheel 36 from one direction by a spring 36b1.

The auxiliary cylinder 33 has a right-hand thread 33a on its inner circumference and is screwed to the right-hand thread 31b of the shaft 31. Also,
On the outer circumference of the auxiliary cylinder 33, there are serrations 33b and a left screw 3
3c is formed, and the left screw 33c is formed on the lead of about 2 to 3 mm.

The brake cylinder 35 has a left screw 35a on the inner circumference and is screwed to the left screw 33c of the auxiliary cylinder 33. One surface of the brake cylinder 35 has a brake pad 36.
A pressing surface 35b for pressing the ratchet wheel 36 against the disk 32 via a and 36a is formed, and engaging projections 35c, 35c ... Are provided on the other surface in the axial direction. The cylindrical portion 35 forming the outer circumference of the left screw 35a
d and the engaging projections 35c, 35c ...
e is attached (FIGS. 4 and 5).

The drive member 34 has serrations 34 on its inner circumference.
While forming a, it has claws 34b, 34b ... on its outer circumference (FIGS. 3 and 4), and is fitted to the serration 33b of the auxiliary cylinder 33 so as not to rotate relative to it. The engagement protrusions 35 c, 35 of the brake cylinder 35 are provided on one surface of the drive member 34.
The engaging projections 34c, 34c, ... Corresponding to c ... are provided to project in the axial direction (FIGS. 4 and 5), and the spring 35e is locked at both ends by the engaging projections 35c, 34c. The driving member 34 is wound around the brake cylinder 35 in the winding direction (see FIGS. 4 and 5).
Direction (arrow K1). Therefore, the driving member 3
No. 4 cannot rotate relative to the brake cylinder 35 in the winding direction, and can slightly rotate in the winding direction (arrow K2 direction in the figure) against the spring 35e.

On the other surface of the drive member 34, a large engagement projection 34d is provided so as to project (FIGS. 3 and 4), and screw holes 34e, 34e are formed at symmetrical positions.

A small-diameter serration 31c is formed on the shaft end of the shaft 31, and a stopper plate 31d is attached to the serration 31c via a snap ring 31e so as not to rotate relatively. Stopper plate 31
d has a protrusion 31d1, and the protrusion 31d1 is the driving member 3
By engaging with the engagement protrusion 34d of No. 4, the relative rotation range of the drive member 34 and the auxiliary cylinder 33 with respect to the shaft 31 is limited to less than one rotation.

The chain wheel 38 is relatively rotatably fitted to the other side of the shaft 31 (FIG. 3). In addition, the chain wheel 38
Is rotatable with respect to the plate members 21 and 21 constituting the frame body 20 via the bushes 38a and 38a on both sides.

The frame body 20 includes bolts 22 and 22 of both screws.
..., nuts 22a, 22a ..., washers 22b, 22b
, A pair of plate members 2 through the spacers 22c, 22c.
1 and 21 are assembled in parallel (FIGS. 1 and 3). In addition, the hook 2 is provided on the upper portion of the frame body 20 through the pin 23a.
3 is attached. However, the hook 23 is the pin 23
It is rotatable around a.

The speed reducing mechanism including gears 37a, 37b, 37b, 37c is housed in a cover 24 attached to the outside of one plate member 21 (FIGS. 2 and 3). That is,
The shaft end of the shaft 31 is rotatably supported by the central portion of the cover 24, and the small-diameter gear 37 a is fixed to the shaft end of the shaft 31. Further, between the plate member 21 and the cover 24,
Auxiliary shafts 37d, 37d are rotatably arranged parallel to the shaft 31, and a small-diameter auxiliary gear 37d1 is fixed to each auxiliary shaft 37d in addition to a large-diameter gear 37b meshing with the gear 37a. There is. However, each auxiliary gear 37d1 is in common mesh with a gear 37c fixed to one end of the chain wheel 38.

Then, when the shaft 31 is rotated, the chain wheel 38
Are gears 37a, 37b, 37b, auxiliary shafts 37d, 37
d, through auxiliary gears 37d1, 37d1, and gear 37c,
The shaft 31 can rotate at a low speed relative to the shaft 31. At this time, the shaft 31 and the chain wheel 38 rotate in the same direction. A chain 25 with a hook 25a is wound around the chain wheel 38 (FIGS. 1 and 2). However, the chain wheel 38 does not move the chain 25 so that the chain 25 does not move relative to each other.
It shall be finished to an outer shape that conforms to the shape and pitch of No. 5.

The rocking lever 10 has a base member 10a whose distal end is formed in a rectangular tube shape and whose base is formed in a groove shape with an open inner surface of a rhombus, and a bracket member 10 accommodated in the base member 10a.
b in combination (FIGS. 1 and 6). The base material 1
A rubber grip 11 is attached to the tip of 0a. Further, the base material 10a and the bracket material 10b are composed of spacers 10c1, 10c1, ...
, 10c2, and bolts 10c3, 10c3, ..., Assembled integrally (FIGS. 3 and 7).

The swing lever 10 as a whole is connected to one side of the frame body 20 via a spacer cover 12,
The brake mechanism 30 assembled to the frame body 20 is housed in the base portion of the swing lever 10 and is covered by the spacer cover 12. A cylindrical opening 13 is formed at the base of the swing lever 10 so as to be common to the base material 10a and the bracket material 10b (FIGS. 3 and 6). 31 and an auxiliary cylinder 3 attached to the shaft 31
3, a part of the brake mechanism 30 including the drive member 34 and the brake cylinder 35 is inserted.

At both ends of the opening 13, a base material 10a, an annular rib 13a facing outward with respect to the bracket material 10b,
13a is formed, and small holes 13a1, 13a1 ... Are formed in the rib 13a on the bracket material 10b side. Further, the spacer cover 12 is formed with a large-diameter opening 12a at the top for inserting the rib 13a. Therefore, the swing lever 10 has the rib 13 with respect to the opening 12a.
By fitting a and fitting a snap ring 13b with claws 13b1, 13b1 ... From the outside of the rib 13a, the spacer cover 12 and the frame body 20 are reciprocally swingably and detachably connected. ing. However,
The claws 13b1 of the snap ring 13b correspond to the small holes 13a1 of the rib 13a, and at this time, the shaft 31 of the brake mechanism 30 is located at the center of the openings 13 and 12a. That is, by swinging the swing lever 10 back and forth with respect to the spacer cover 12,
It can be rocked back and forth around the shaft 31.

At the tip of the brake mechanism 30 penetrating the base of the rocking lever 10, set screws 14a, 14a are provided,
A circular handwheel cover 14 is attached (FIG. 1,
(Figure 3). The set screws 14a and 14a are used for the driving member 3
4 screw holes 34e, 34e. Further, a compression spring 14b is provided on the inner surface of the cover 14 between the cover 14 and the stopper plate 31d.

The swing lever 10 includes a bracket member 10b.
The switching claw 15 is incorporated through the switch (FIGS. 3 and 7). The switching claw 15 has an engaging portion 1 that opens in a V shape on one side.
5a and 15a are formed, and a smooth concave portion 15 is formed on the other side.
b, 15b ... Are formed, and the hexagonal hole 15 is formed in the central portion.
It is a deformed plate material forming c. A switching knob 15d is attached to the switching claw 15, and the switching knob 15d is rotatably attached to the swing lever 10 via bushes 15e on both sides. Also, switch knob 1
The 5d hexagonal shaft 15d1 fits into the hexagonal hole 15c of the switching claw 15 and is inserted into the hexagonal hole 15c. A leaf spring 15f is attached to the rear portion of the switching claw 15 via spacers 10c1 and 10c1. The central portion of the leaf spring 15f is slightly bulged toward the switching claw 15 so that the recess 15
b, 15b ... Further, the engaging portions 15a, 15a of the switching claw 15 are the claws 34b on the outer periphery of the drive member 34,
34b ... (FIG. 2).

Therefore, the switching claw 15 has a switching knob 15d.
, One of the engaging portions 15a, 15a can be switch-engaged with the claws 34b, 34b, ... Of the drive member 34. At this time, the leaf spring 15f directs the switch claw 15 toward the drive member 34. By lightly urging, the switching claw 15 can be elastically fixed at a predetermined position.

That is, the switching claw 15 is switched as shown in FIG. 2 so that one of the engaging portions 15a is claw 34 of the drive member 34.
When the rocking lever 10 is reciprocally rocked up and down by engaging with b, 34b, ..., When the rocking lever 10 moves upward (direction of arrow K3 in FIG. 2), the driving member 34 is driven in the winding direction. However, when the swing lever 10 moves downward (in the direction of arrow K4 in the figure), no force is exerted on the drive member 34. The switching claw 15 switches this in reverse, and the other engaging portion 15a is claws 34b, 34.
When engaged with b ..., the drive member 34 can be driven in the lowering direction only when the swing lever 10 moves downward. Therefore, the switching claw 15 can be switched and fixed to either of them via the leaf spring 15f by defining the former position as the winding position and the latter position as the lowering position. Further, the switching claw 15 can also be switched to a neutral position in which none of the engaging portions 15a, 15a is engaged with the claws 34b, 34b.

On the surface of the oscillating lever 10, a switching name plate is displayed in order to display the winding position, the lowering position, and the neutral position of the switching pawl 15 which is switched and fixed in this way, depending on the switching angle of the switching knob 15d. 15g is screwed (Fig. 3).

The operation of the chain lever hoist is as follows.
It is as follows.

First, the brake cylinder 35 of the brake mechanism 30.
By advancing toward the disc 32, the ratchet wheel 36 can be sandwiched between the ratchet wheel 36 and the disc 32 via the brake pads 36a, 36a, and the ratchet wheel 36 can be non-rotatably restrained. The ratchet wheel 36 is prevented from rotating in the unwinding direction via the lock claw 36b.

On the other hand, when the whole is suspended at an appropriate height position through the hook 23, the chain 25 hangs downward from the chain wheel 38 on both sides. Therefore, when the switching claw 15 is set to the neutral position via the switching knob 15d and the cover 14 is manually rotated to slightly rotate the drive member 34 in the unwinding direction with respect to the shaft 31, the drive member 34 is moved to the auxiliary cylinder. 33, the brake cylinder 35 can be retracted in the direction away from the disc 32, the ratchet wheel 36 can be released, and the shaft 31 can be rotated. The auxiliary cylinder 33 includes serrations 34a,
33b rotates integrally with the driving member 34 via the right screw 3
While moving in the direction away from the disc 32 via the 3a and 31b, the brake cylinder 35 has a left-hand thread 33 even if the pressing surface 35b is in close contact with the brake pad 36a.
With c and 35a, it is possible to retract in the same direction as the auxiliary cylinder 33 without rotating itself, and if the pressing surface 35b is not in close contact with the brake pad 36a,
This is because it is possible to rotate integrally with the drive member 34 and the auxiliary cylinder 33 via the spring 35e and to retract together with the auxiliary cylinder 33.

Then, by pulling down one side of the chain 25, the hook 25a at the tip of the chain 25 is set at an appropriate height position, and the switching claw 15 is switched to the winding position.
At this time, the relative rotational positions of the shaft 31 and the drive member 34 are maintained in the state at the time when the ratchet wheel 36 is released, and even if the chain 25 is moved, the ratchet wheel 36 is inadvertently restrained. The shaft 31 does not become unrotatable. A compression spring 14b is interposed between the cover 14 and the stopper plate 31d, and the compression spring 14b exerts an appropriate frictional force between them,
This is because it acts so as not to change the relative rotational position between the shaft 31 and the drive member 34.

Next, when a load (not shown) is connected to the hook 25a and the swing lever 10 is swung up and down, the swing lever 10 drives the driving member 34 in the winding direction via the switching pawl 15. You can When the drive member 34 rotates in the winding direction, the auxiliary cylinder 33 advances toward the disc 32 by the right screws 33a and 31b, and the brake cylinder 3
5 presses the ratchet wheel 36 against the disc 32 via the brake pads 36a, 36a, and restrains the ratchet wheel 36. Brake cylinder 35 at this time
The engaging protrusions 34c, 34c ..., 35c, 35c ... are engaged in the winding direction, so that the driving member 34 and the auxiliary cylinder 33 rotate integrally with each other, and the auxiliary cylinder 33 can move forward together. Because you can.

Therefore, when the swing lever 10 is further swung back and forth to drive the drive member 34 in the winding direction, the force applied to the swing lever 10 is the drive member 34 and the brake cylinder 3.
5, transmitted to the shaft 31 via the brake pads 36a, 36a, the ratchet wheel 36, and the disc 32,
Gears 37a, 37b, 37b, auxiliary shafts 37d, 37d,
The load is transmitted to the chain wheel 38 through the auxiliary gears 37d1, 37d1 and the gear 37c, and the load can be wound up through the chain 25. Also, at this time, the ratchet wheel 36
Since the rotation in the lowering direction is prevented via the lock claw 36b, the load does not inadvertently descend when the swing lever 10 is swung downward. Further, the force applied to the rocking lever 10 is sufficient with a sufficiently small operating force even if the load is heavy due to the reduction mechanism extending from the gear 37a to the gear 37c.

The load thus wound can be safely and lightly wound by switching the switching claw 15 to the lowering position and reciprocally swinging the swing lever 10 up and down. When the switching claw 15 is switched and fixed to the lowering position, the swing lever 10 can drive the driving member 34 and the auxiliary cylinder 33 in the lowering direction, and at this time, the auxiliary cylinder 33 is rotated by the right-hand screws 33a and 31b. This is because the ratchet wheel 36 can be released by releasing the shaft 31 and the chain wheel 38 via the lever so as to be rotatable. When the ratchet wheel 36 is released and the chain wheel 38 is driven in the lowering direction by the load, the shaft 31 is driven in the lowering direction via the reduction mechanism, and the drive member 34 is relatively moved in the winding direction. Driven to. So ratchet wheel 36
Is immediately reconstrained and the load can be safely unwound as the drive member 34 rotates.

At this time, even if the brake cylinder 35 is in close contact with the brake pad 36a, the driving member 34 is
When the auxiliary cylinder 33 is driven in the lowering direction and is driven in the lowering direction, the auxiliary cylinder 33 retracts along the shaft 31 via the right-hand screws 33a and 31b, and therefore the brake cylinder 3
5 can be retracted in the axial direction without rotating via the left screws 33c and 35a to release the ratchet wheel 36. Therefore, the swing lever 10 does not have an excessive initial required operation force.

In the above description, the brake mechanism 30
Can be widely applied to not only chain lever hoists but also other types of manual or electric hoists. Further, at that time, the output chain wheel 38 can be replaced with an arbitrary winding mechanism such as a drum around which the wire is wound. The driving member 34 may be driven in the forward and reverse directions by an electric motor instead of being driven through the swing lever 10 and the switching claw 15, or may be driven through an appropriate handle or chain. . Further, the disk 32 and the gear 37a may be integrally formed with the shaft 31, respectively, and the gear 37c and the auxiliary gear 37d1 may be integrally formed with the chain wheel 38 and the auxiliary shaft 37d, respectively. Good.

The left screws 33c and 35a for screwing the auxiliary cylinder 33 and the brake cylinder 35 may be replaced with right screws. However, the lead of the right-hand screw at this time must be smaller than the leads of the right-hand screws 31b and 33a that screw-connect the shaft 31 and the auxiliary cylinder 33. Drive member 3
4 is driven in the lowering direction to lower the load, the amount of retreat of the brake cylinder 35 depends on the right screw and the right screw 31b, 3b.
This is because it is determined by the lead difference of 3a.

The speed reducing mechanism from the gear 37a to the gear 37c can be replaced by any type other than the one shown.
The winding mechanism such as the chain wheel 38 or a drum replacing the chain wheel 38 is arranged on an extension line of the shaft 31, or is arranged independently of the shaft 31, and is connected to the shaft 31 via a reduction mechanism. You may

[0055]

As described above, according to the first aspect of the present application, the drive member, the auxiliary cylinder screwed to the shaft through the right screw, and the brake cylinder screwed to the auxiliary cylinder are provided. By providing the brake cylinder, when the drive member is driven in the lowering direction, even if the brake cylinder is in close contact with the brake pad, the brake cylinder retracts in the axial direction without rotating to release the ratchet wheel, and the shaft is rotated. Since it can be freely rotated, there is no fear that the operating force becomes excessive when winding down the load, and there is an excellent effect that extremely excellent operability can be easily realized.

According to the second invention, there is an effect that the same effect can be achieved by incorporating the brake mechanism according to the first invention.

[Brief description of drawings]

1 is a perspective view of the overall configuration

FIG. 2 is a perspective view of a main part.

FIG. 3 is a cross-sectional view of the main configuration

FIG. 4 is an exploded perspective view of essential parts (1)

5 is a cross-sectional view taken along line XX of FIG.

FIG. 6 is an exploded perspective view of essential parts (2)

FIG. 7 is an exploded perspective view of essential parts (3)

FIG. 8 is an explanatory perspective view showing a conventional technique.

[Explanation of symbols]

 10 ... Swing lever 12 ... Spacer cover 13 ... Opening 13b ... Snap ring 15 ... Switching claw 15f ... Leaf spring 20 ... Frame 25 ... Chain 25a ... Hook 30 ... Brake mechanism 31 ... Shaft 32 ... Disc 33 ... Auxiliary cylinder 31b , 33a ... right-hand screw 34 ... driving member 35 ... brake cylinder 35e ... spring 36 ... ratchet wheel 36a ... brake pad

Claims (5)

[Claims] 1. A shaft for driving a winding mechanism for output through a reduction mechanism, a disk rotating integrally with the shaft, an auxiliary cylinder screwed to the shaft through a right-hand screw, and the auxiliary cylinder. A drive member that rotates integrally, and a screw connection to the auxiliary cylinder,
A brake cylinder that is driven by the drive member in the winding direction, a ratchet wheel that is sandwiched between the disc and the brake cylinder via brake pads on both sides, and the drive member is biased in the winding direction with respect to the brake cylinder. A braking mechanism such as a hoist that includes a spring. 2. A brake mechanism for a hoist or the like according to claim 1, wherein the screw for screw-connecting the auxiliary cylinder and the brake cylinder is formed in a lead smaller than the right-hand thread. 3. The brake mechanism according to claim 1, a swing lever that swings back and forth around the shaft, and drives the drive member in a predetermined direction via a switching claw, and an output lever. A frame for housing the chain wheel and assembling the speed reduction mechanism,
A chain lever hoist comprising a chain with a hook that is wound around the chain wheel. 4. The chain lever hoist according to claim 3, wherein the switching claw is switchably fixed to a winding position, a neutral position, and a winding position via a leaf spring. 5. The swing lever has an opening at the base for inserting the brake mechanism in the axial direction, the frame body has a spacer cover for covering the brake mechanism, and the swing lever comprises: The chain lever according to claim 3 or 4, wherein the top of the spacer cover is relatively rotatably fitted in the opening with respect to the frame, and is detachably connected via a snap ring. Hoist.