JPS6374895A - Safety device for traction winding machine - Google Patents

Abstract

(57) [Abstract] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a safety device for a lever set or a hand chain wheel type towing hoist.

[Conventional technology and its problems]

Conventionally, as a safety device for preventing forcible towing or hoisting exceeding a predetermined limit value, for example, the Japanese Utility Model Publication No. 48-4031
No. 6 is known, but when the load exceeds a certain limit, the claw of the switching pawl plate comes off the special tooth shape of the switching wheel, causing the lever to spin idly. Although this seems reasonable at first glance, it is extremely dangerous when working at heights. In other words, if a worker at a high place is pushing down or pulling the lever or hand chain of a towing hoist with all his might, and the lever or hand chain suddenly spins, he may fall unexpectedly and cause personal injury. [Means for solving the problem] The safety device for a towing hoist according to the present invention is equipped with a drive transmission member that transmits the rotation of the tonneau on the side of an operating member such as a lever or a hand mirror. A safety device for a traction hoist, wherein the drive transmission member includes: a main body having an uneven surface formed on the outer circumferential surface and a screw hole in which the shaft center hole is screwed into the screw of the drive shaft; It is made to be able to slide in sliding contact with the uneven surface of the main body and move in the inner and outer radial directions, and if the rotational torque is less than a predetermined limit value, there is a gap between the uneven surface and a fixed part such as the inner circumferential surface of the housing cover. Due to the elastic force of the interposed elastic member, the abutting portion abuts against the recess of the uneven surface to form a predetermined gap with the fixed portion, and the rotational torque is within a predetermined limit value. If this is the case, the corresponding contact portion corresponds to the convex portion of the uneven surface, so that it moves sequentially in the outer radial direction against the elastic force of the elastic member, and comes into pressure contact with the fixed portion. and a movable member that does not move the operating member.

[Effect]

With the above configuration, if the rotational torque is less than the predetermined limit value, the driving force transmission member can rotate because a predetermined gap is formed between the movable member and the fixed portion. Also,
When the rotational torque reaches a predetermined limit or more, the movable member sequentially moves in the outer radial direction and presses against the fixed part and does not move the operating member, so that the operating member will not suddenly idle during operation.

〔Example〕

Hereinafter, the present invention will be explained in detail based on drawings showing examples.

FIG. 1 shows a traction hoisting machine according to the present invention, and this traction hoisting machine is equipped with a drive transmission member 20 for transmitting rotational torque on the side of an operating member I such as a lever or a hand mirror.

In this drive transmission member 20, the shaft center hole is the drive main shaft 8.
It consists of a main body 20a having a screw hole 24 that is screwed into the screw 10, and a movable member 20b that is movable in the inner and outer radial directions, and when the rotational torque reaches a predetermined limit value or more,
The operating member 1 is not moved.

Further, a brake desk hub 11 is screwed onto the screw 10 of the drive main shaft 8. That is, this hub 11 is integrally formed of a small-diameter cylindrical portion 13 and a large-diameter disk portion 14, and two brake disks 15 and 16 are fitted onto the outer peripheral surface of the small-diameter cylindrical portion 13. A ratchet disk 17 is disposed sandwiched between the brake disks 15 and 16. This ratchet desk 17 has many inclined teeth 18 on the outer periphery.
A claw (not shown) is always elastically pressed toward the tooth 18 by a spring, allowing rotation in only one direction. A cover 28 is fixed to the inner peripheral surface of the bolt 29 in the housing 2.

Thus, the main body 20a has an uneven surface 35 formed on its outer peripheral surface, and its inner end surface contacts the brake disk 16.

In addition, the movable member 20b, as shown in FIGS. 2 and 3,
the uneven surface 35 and the fixing portion 30 on the inner circumferential surface of the cover 28;
It consists of a rod-like body that is resiliently biased in the inner radial direction by the resilient force of the resilient member 27 interposed therebetween. Specifically, the movable member 20b is disposed in the radial direction on an outer cylindrical body 20c that is fitted onto the main body 20a, and the abutment portion 38 at the tip of the movable member 20b contacts the resilient member 2.
At 7, it comes into sliding contact with the uneven surface 35.

Further, this elastic member 27 is housed inside a hollow elastic member storage chamber 40 provided in the outer cylinder 20C, and the movable member 2
It is locked to the outer flange 41 of 0b. Reference numeral 31 denotes a concave-convex toothed portion provided on the outer circumferential surface of the outer cylinder body 20C, on which a tip claw portion 33 of a lever bowl 32 attached to the operating member 1 so as to be movable in the axial direction is removably engaged therewith. .

Thus, if the rotational torque m is small and is less than the predetermined limit value, the abutting portion abuts against the recess 37 of the uneven surface 35 to form a predetermined gap A with the fixed portion 36.

In other words, the driving force transmission member 20 is rotatable.

Also, if the rotational torque M becomes large, exceeding a predetermined limit value,
As shown in FIG.
7 to correspond to the convex portion 38, the movable member 20b moves in the outer radial direction against the elastic force of the elastic member 27, and the predetermined gap A becomes zero, and the outer end of the movable member 20b is connected to the housing. 2
It comes into pressure contact with the fixed part 30 of and brakes the rotation. In other words, the operating member 1 does not move.

Next, FIGS. 4 to 7 show another embodiment, and this driving force transmission member 20 includes a main body 20a having a wavy uneven surface 35 on a part of the outer circumference, and a recess 37 of the uneven surface 35. It consists of a roller-shaped movable member 20b and an outer cylindrical body 20c that is fitted onto the roller-shaped movable member 20b and holds a large number of roller-shaped movable members 20b through elastic members 27 made of plastic, rubber, etc. A fixed portion 30 is provided with an inwardly extending portion protruding from the inner peripheral surface of the housing 2 corresponding to the exposed portion of the movable member 20b.
When the rotational torque is small, there is a predetermined gap A as shown in FIGS. 4 and 5, but when the rotational torque M exceeds the predetermined limit value, the elastic member 27 is compressed and the movable member 20b moves in the outer radial direction. The rotation of the driving force transmitting member 20 is stopped when the driving force transmitting member 20 is moved to and comes into pressure contact with the fixed part 30.

It should be noted that the present invention is of course not limited to the above-described embodiments, but it is also possible to apply this safety device to a towing hoist for a handcar, for example. Furthermore, the fixed portion to which the movable member 20b is pressed may be any member other than the housing 2 or the cover 28, and a wear-resistant member may be interposed therebetween.

〔Effect of the invention〕

The safety device for a towing hoist according to the present invention has the above-described configuration, so that if the load is below a predetermined limit value, the load is hoisted by operating the operating member 1 such as a lever or a hand mirror. When the load exceeds a predetermined limit value (overload), even if the operating member 1 is not operated, the movable member 2
0b is pressed against the fixed part 30 and is braked, which can prevent damage to the gear mechanism and the like and play a role of security, especially when a worker is pushing and pulling the operating member 1 while climbing to a high place. Since there is no possibility of sudden idling, and the operation member 1 only stops if it is overloaded, it is possible to completely prevent the danger of workers falling from a high place, and to avoid sudden shocks. This has a significant effect in that the operation can be performed smoothly.

[Brief explanation of the drawing]

Fig. 1 is an enlarged sectional view of main parts showing one embodiment of the present invention;
The figure is a sectional view taken along the line DD in Fig. 1 with some parts omitted, Fig. 3 is the same sectional view when overloaded, and Fig. 4 is an enlarged sectional view of main parts of another embodiment. , FIG. 5 is a sectional view taken along line E-E in FIG. 4,
Figure 6 is the same cross-sectional view when overloaded. Figure 7 is H-H in Figure 4.
It is an Ir plane view. DESCRIPTION OF SYMBOLS 1... Operation member, 2... Housing, 8... Drive main shaft, 10... Screw, 20... Drive transmission member, 20
a... Main body, 20b... Movable member, 27... Resilient member, 28... Cover, 30... Fixed part, 35...
- Uneven surface, 37... recessed part, 38... contact part, 39.
・Convex part. Patent applicant Nakamoto Iron Works Co., Ltd. Figure 1 Figure 2 Figure 3

Claims (1)

[Scope of Claims] 1. A safety device for a traction hoist comprising a drive transmission member 20 that transmits rotational torque on the side of an operating member 1 such as a lever or a hand mirror, wherein the drive transmission member 20 has an outer circumferential surface. The main body 20 has an uneven surface 35 formed therein, and a shaft center hole that is a screw hole 24 that is screwed into the screw 10 of the drive shaft 8.
a, and is movable in the inner and outer radial directions by slidingly contacting the uneven surface 35 of the main body 20a, and if the rotational torque is less than a predetermined limit value, the uneven surface 35 and the inner periphery of the housing 2/cover 28 A resilient member 27 interposed between a fixed part 30 such as a surface, etc.
With the elastic force of , the contact part 38 contacts the recess 37 of the uneven surface 35 to form a predetermined gap A between the contact part 38 and the fixed part 30,
Moreover, when the rotational torque exceeds a predetermined limit value, the corresponding contact portion 38 corresponds to the convex portion 39 of the uneven surface 35, thereby resisting the elastic force of the elastic member 27 and moving in the outer radial direction. A safety device for a traction hoist, comprising: a movable member 20b that moves sequentially and comes into pressure contact with the fixed part 30, thereby preventing the operating member 1 from moving.