JPS63713Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a chain hoist, and more particularly to a chain hoist in which the length of an operating chain wound around a chain sprocket is variable.

As shown in FIGS. 1 and 2, a conventional chain hoist of this kind includes a chain sprocket 42 which is rotatably mounted on a drive shaft 41 within a hoist body 40, and a ring-shaped operating chain 43 of a predetermined length is connected to the chain sprocket 42. It has a configuration in which it is wound around a chain sprocket 42 and suspended at a constant length.

However, in the conventional chain hoist as described above, the length of the operating chain 43 is constant, so if the operating chain 43 is suspended in a place with a step, the operating chain 43 will not touch the floor at a high position. A similar situation may occur due to a design error in the chain hoist itself. in this way,
When the operating chain 43 drags on the floor, this causes dust, sand, soil, etc. on the floor to be kicked up, and the engagement between the operating chain 43 and chain sprocket 42 causes this dust to fall. However, when a chain hoist is used for disassembling or maintaining a machine, there is a drawback that the falling dust has a negative impact on the machine. Furthermore, when a conventional chain hoist is used as an overhead hoist, the length of the operating chain is determined in advance for each specification, making it difficult to standardize. Furthermore, when traveling an overhead hoist as described above, if there is a risk that the hoist operation chain may get caught in an obstacle within the traveling range, there is the trouble of having to traverse the hoist to avoid this. There were major inconveniences in use, such as the need for manipulation.

Therefore, in view of the above-mentioned conventional circumstances, the present invention has two chain sprockets that are connected to a hoist drive shaft and around which a single operating chain is wound, and a system that transfers the rotational power of one chain sprocket to the hoist drive shaft. The structure includes a clutch device for transmitting power to the engine, and a speed governor for each of the two chain sprockets, so that the length of the operating chain can be adjusted as necessary, thereby preventing the operating chain from dragging on the floor, etc. To provide a chain hoist which eliminates all inconveniences in use, such as being able to prevent interference from obstacles.

Hereinafter, one embodiment of the present invention will be described based on FIGS. 3 to 5.

3 and 4, 17 is a hoist main body, 18 is a hoist hanging hook fixedly attached to the upper part of the hoist main body 17, 12 is a hoist drive shaft protruding from the end surface of the hoist main body 17, 1
9 is a lifting hook that moves up and down as the hoist drive shaft 12 rotates.

Reference numeral 1 indicates a first chain sprocket that is pivotally attached to the hoist drive shaft 12, 2 indicates a second chain sprocket that is rotatably supported on the hoist drive shaft 12, and 20 indicates the hoist drive shaft 12 and the A clutch device 21 is provided between the hoist and the second chain sprocket 2 and transmits the rotational power of the second chain sprocket 2 to the hoist drive shaft 12, and selectively connects and disconnects the power transmission. When the power transmission by the clutch device 20 is disconnected, the rotation of one of the first and second chain sprockets 1 and 2 is decelerated and transmitted to the other chain sprocket 2, and the rotation of the other chain sprocket 2 is reduced. a speed governor for increasing the speed of the rotation of the sprocket 2 and transmitting it to the one chain sprocket 1;
3 is the first and second chain sprocket 1, 2
It is a single ring-shaped operating chain that is wrapped in a cross-over manner.

That is, the first chain sprocket 1 is fixedly attached to the outer periphery of the hoist drive shaft 12 near the end wall of the hoist main body 17 with a key 13. Second
The chain sprocket 2 is the hoist drive shaft 12
It is rotatably supported via a ball bearing 14 at a position near the first chain sprocket 1 on the outer periphery. The clutch device 20 includes a clutch body 2 that becomes an idling gear case, which will be described later.
2, and clutches 23 and 24 provided between the clutch body 22 and the second chain sprocket 2 and between the clutch body 22 and the fixed plate 10 side of the hoist body 17, respectively.
The clutch main body 22 has a substantially cylindrical protruding portion 22a at one end, and a substantially cylindrical member 22A having an open end at the other end, and a fixing member 25a such as a bolt on the open end surface of the member 22A. It consists of a fixedly attached ring-shaped plate member 22B and is formed in a hollow shape, and the ring-shaped plate member 22B is located close to the second chain sprocket 2 and its center axis is the center of the hoist drive shaft 12. placed in matching positions. One clutch 23 is provided between a surface of a ring-shaped plate member 26 fixed to the end surface of the second chain sprocket 2 by a fixture 25b and a peripheral surface of the ring-shaped plate member 22B of the clutch body 22. ing. The other clutch 24 has a screw at the end of a fixed shaft 27 which is disposed so as to face the end surface of the protrusion 22a of the clutch body 22 and the end surface of the hoist main body 17 with a predetermined distance therebetween, and which extends horizontally from the end surface of the hoist main body 17. Natsu 2 in part 27a
8 is provided between the center surface of the fastened fixing plate 10. The clutches 23, 24 are selectively engaged and engaged by the sliding action of the clutch ring 7. The clutch ring 7 is fitted into an annular groove 22b formed on the outer periphery of the protrusion 22a of the clutch body 22, and is in contact with the wear ring 11 disposed in the groove 22b and the inner end surface of the groove 22b. The clutch ring 7 is pressed in a direction away from the fixing plate 10 by a compression spring 8 interposed between its outer end surface and the inner end surface of the fixing plate 10, thereby pushing the clutch body 22 in the same direction. By pressing, the clutch 23 is normally kept in the connected state and the clutch 24 is kept in the disconnected state.

The clutch ring 7 is connected to a clutch arm 9 rotatably supported on a fixed plate 10, and is slid by the up and down movement of the clutch arm 9 to connect and disconnect the clutches 23 and 24. It's becoming like that. Note that 29 is a string for operating the clutch arm 9. Next, the speed governor 2
1 is constructed as follows. That is, low speed gear 4
is fixed to the center of the second chain sprocket 2 by a key 15 so as to rotate together with the second chain sprocket 2. This low speed gear 4
is meshed with a small gear 3A serving as an idling gear 3 rotatably supported by the clutch body 22. The high-speed gear 5 is fixed to the outer periphery of the hoist drive shaft 12 by a key 16, and is designed to rotate together with the hoist drive shaft 12. This high-speed gear 5 is meshed with a large gear 3B serving as an idling gear 3. The small gear 3A and the large gear 3B are fixed via keys 31 and 32, respectively, to the outer periphery of a rotating shaft 30 whose both ends are rotatably supported by the clutch body 22. On the other hand, as described above, the operating chain 33 is wound across the two chain sprockets 1 and 2 as shown in FIG. The part that reaches the sprocket 1 extends downward and serves as an operating section.

Next, the operation and usage of the above chain hoist will be explained.

First, when the clutch 23 is in the connected state, the clutch body 22 is connected to the second chain sprocket 2.
Since the gears 3, 4 and 5 do not function as gears, they are connected to the second chain sprocket 2.
is substantially fixed to the hoist drive shaft 12, and the rotation of the sprocket 2 is transmitted to the hoist drive shaft 12. On the other hand, when the clutch 24 is in the connected state, the clutch body 22 is fixed to the fixed plate 10 and does not rotate. In this state,
When the second chain sprocket 2 is rotated, its rotation is accelerated by the idling gear 3 and transmitted to the hoist drive shaft 12, causing the first chain sprocket 1 to rotate. Conversely, when the first chain sprocket 1 is rotated, its rotation is decelerated by the idling gear 3 and transmitted to the second chain sprocket 2, which rotates.

Now, when the operating chain 33 is pulled out with the clutch 23 connected as described above, the intermediate portion 33B of the operating chain 33 and the operating section 3
The position of 3A remains unchanged, the hoist drive shaft 12 can be rotated in either direction, and the hoisting hook 19 can be moved up and down to perform hoisting operations.

Pull the clutch arm operating string 29 downward,
When the clutch ring 7 is moved to the right in Fig. 4,
The clutch body 22 is slid to the right against the spring force of the spring 8, and at the same time the clutch 23 is disconnected, the clutch 24 is now connected. While maintaining this state, operate chain 3.
3 in the lifting direction shown in Figure 5.
When the chain sprocket 1 is rotated in the direction of arrow A in the figure, the second chain sprocket 2 is rotated in the same direction.
The second chain sprocket 2 rotates at a lower speed than the first chain sprocket 1. Therefore, since the length of the operating chain 33 fed out by the second chain sprocket 2 is shorter than the length of the operating chain 33 hoisted up by the first chain sprocket 1, the length of the intermediate portion 33B of the operating chain 33 becomes shorter. The operating section 33A of the operating chain 33 is in an elongated state. Next, when the operating chain 33 is pulled in the hanging direction shown in FIG. 5 and the second chain sprocket 2 is rotated in the direction of arrow B in the figure, the first chain sprocket 1 is rotated.
rotate in the same direction, in which case the first chain sprocket 1 rotates faster than the second chain sprocket 2. Therefore, the middle portion 33B of the operation chain 33 becomes longer, and the operation chain 3 becomes longer.
The operating section 33A of No. 3 is in a shortened state.

Through the above operations, the operation chain 33
After adjusting the length to the desired length, loosen the clutch arm operating string 19, and the spring 8 will push the clutch body 22 to the left in FIG. 4, and the clutch 23 will be in the connected state. , the clutch 24 is in the disengaged state and normal hoisting operations can be performed.

According to the chain hoist with the above configuration, the length of the operation chain 33 can be adjusted arbitrarily,
This prevents the operating chain from sagging and dragging on the floor as in the conventional case, and thereby prevents the inconvenience caused by the operating chain lifting up dust, sand, soil, etc., and causing it to fall. This eliminates the inconvenience of pouring it onto the machine during disassembly and maintenance. Incidentally, in this embodiment, the length of the operation chain can be adjusted so that the shortest and longest lengths are about twice as long. Furthermore, when such a chain hoist is used as an overhead hoist, even if there is an obstacle within the movement range of the operating chain, the obstacle can be avoided by adjusting the length of the operating chain with a simple operation. , there is no need for the troublesome work of traversing the hoist to avoid obstacles as in the past. Furthermore, in the case of conventional overhead hoists, the length of the operation chain was determined for each specification and could not be standardized, but with this chain hoist, there is no need to determine the length of the operation chain for each specification and standardization is possible. can be done easily.

Further, in the chain hoist having the above structure, the normal hoist operation and the operation chain length adjustment operation can be easily switched by selectively intermittent operation of the clutch device 20. This can also be done by a simple operation of pulling the operation chain 33 through the action of the speed governor 21, which provides excellent operability and improves the work efficiency.

In the above configuration, if the chain sprocket 1 that performs the lifting operation and the chain sprocket 2 that performs the suspending operation are reversed, the large gear 3B can be attached when installing the large and small gears 3B and 3A of the idling gear. The configuration may be such that the low speed gear 4 and the small gear 3A are meshed with the high speed gear 5, respectively.

As explained above, according to the present invention, the length of the hoist operation chain can be increased by combining the first and second chain sprockets, the clutch device, the speed governor, and the single operation chain. can be easily adjusted, eliminating all the drawbacks of conventional systems in which the length of the operating chain is constant, and has the practical effect of improving workability when using a hoist. It is a big thing.

[Brief explanation of the drawing]

Fig. 1 is a perspective view showing the schematic structure of a conventional chain hoist, Fig. 2 is a longitudinal sectional view showing the chain sprocket of the same chain hoist, and Fig. 3 is a perspective view showing the external appearance of the chain hoist according to the present invention. 4 is a vertical sectional view showing the internal structure of the above chain hoist, and FIG. 5 is a schematic perspective view showing the relationship between the operating chain and the chain sprocket in the above chain hoist. DESCRIPTION OF SYMBOLS 1...First chain sprocket, 2...Second chain sprocket, 3...Idling gear, 4...Low speed gear, 5...High speed gear, 12...
... Hoist drive shaft, 20 ... Clutch device, 21
... Speed governor, 22 ... Clutch body, 23,2
4...clutch, 33...operation chain.

Claims (1)

[Scope of utility model registration request] a first chain sprocket pivotally attached to a hoist drive shaft; a second chain sprocket rotatably supported on the hoist drive shaft; and a connection between the hoist drive shaft and the second chain sprocket. a clutch device provided between the second chain sprocket and the second chain sprocket for selectively connecting and disconnecting the rotational power of the second chain sprocket to the hoist drive shaft; a speed governor that decelerates the rotation of one sprocket of the second chain sprocket and transmits the same to the other sprocket, and increases the speed of the rotation of the other sprocket and transmits the same to the one sprocket;
A chain hoist comprising: a single ring-shaped operation chain that is wound around the first and second chain sprockets in a cross-over manner.