JPH0136992Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a device for lifting and opening the cover of a manhole in an underground cable conduit for communications or electric power, a sewage conduit, or the like.

Conventional devices of this type use hydraulic pressure to lift heavy manhole covers that fit tightly into the manhole frame, so they require expensive hydraulic cylinders, hydraulic pumps, etc., making the device large and expensive. . Therefore, it is conceivable to use a reduction hoist with a simple structure and low cost to lift the manhole cover. However, in order to release the connection between the manhole frame and the heavy manhole cover that is tightly fitted into the manhole frame by hoisting the manhole cover with the deceleration hoist, a very large force is required for the hoisting operation of the deceleration hoist. In the end, in conventional equipment,
Manhole covers cannot be opened easily.

An object of the present invention is to provide a manhole cover opening device that can improve the drawbacks of the conventional devices as described above and can easily open a manhole cover.

This invention applies a lifting force to the manhole cover that is tightly fitted into the manhole frame, and when an impact is applied to the manhole cover, the connection between the manhole frame and the manhole cover loosens, and the manhole cover lifts up due to the lifting force applied to it. It was completed by focusing on the ability to jump up and open the door. That is, a locking device that locks to the opening locking part of the manhole cover is attached to the end of the traction strip such as a chain or wire for hoisting of the reduction hoist, and a locking device is installed in the middle of the hoisting traction strip or when the A manhole cover opening device characterized in that a spring is interposed between the traction strip and the locking device, which deforms when the manhole cover is pulled by the hoisting operation of a deceleration hoist and applies a lifting force to the manhole cover. be.

When using the device of the present invention, the locking device attached to the end of the hoisting traction strip of the deceleration hoist is locked to the opening locking portion of the manhole cover that is tightly fitted into the manhole frame buried in the ground. , by the hoisting operation of the deceleration hoisting machine, the hoisting traction strip is tensed to pull the manhole cover, and the hoisting traction strip is interposed in the middle of the hoisting traction strip or between the hoisting traction strip and the locking device. When the spring is deformed and a lifting force is applied to the manhole cover due to the deformation of the spring, the hoisting operation of the deceleration hoisting machine is stopped, and then the lifting force is applied to the manhole cover to which the lifting force has been applied with a hammer. Apply a shock by hitting it. Then, the impact loosens the connection between the manhole frame and the manhole cover, and the manhole cover flies up and opens due to the elastic force of the deformed spring.

Since the device of the present invention uses a reduction hoist, it has a simpler structure and is cheaper than a device that uses hydraulic pressure. In addition, by deforming the spring interposed in the middle of the hoisting traction strip of the deceleration hoist or between the hoisting traction strip and the locking device, and applying an impact to the manhole cover that provides lifting force, the manhole The lid can be opened. Therefore, compared to the case where the manhole cover is opened only by the hoisting operation of the deceleration hoisting machine,
Less force is required for the hoisting operation of the reduction hoist. After all, the manhole cover can be opened easily.

Next, embodiments of the present invention will be described.

As shown in FIGS. 1 and 2, the device of this example has the following features:
A machine frame 1 is constructed by extending a beam 3 between the upper ends of both inverted T-shaped columns 2, 2 arranged on the left and right sides, and two casters 4, 4 are attached to the lower ends of each column 2 of the machine frame. There is. The box-shaped case 6 of the reduction hoist 5 using a planetary gear train is fixed to the center of the lower surface of the beam 3 of the machine frame, and the box-shaped case 6 of the reduction hoist 5, which uses a planetary gear train, is fixed to the center of the lower surface of the beam 3 of the machine frame. A handle insertion hole 17 facing the handle engagement socket 10 protruding from the front of the case 6
A handle guide plate 16 is provided vertically through the handle guide plate 16.
The hoisting chain 12 that hangs down from the lower surface of the case 6 of the reduction hoist is cut in the middle, and a U-shaped pin 18 is bent at the upper cut end of the chain 12, as shown in FIG. At the same time as connecting the ends, connecting the bent end of the U-shaped pin 19 to the lower cut end of the chain 12,
The upper and lower U-shaped pins 18 and 19 are assembled as shown in FIGS. 4 and 5, and the spring receiving piece 20 loosely fitted to the upper U-shaped pin 18 is fixed to the open upper end of the lower U-shaped pin 19. At the same time, the spring receiving piece 21 loosely fitted to the lower U-shaped pin 19 is fixed to the open lower end of the upper U-shaped pin 18, and the screw spring 22 loosely fitted to the outer periphery of both U-shaped pins 18 and 19 is fixed. A threaded spring 22 is inserted between the upper and lower spring receiving pieces 20 and 21 in the middle of the chain 12. A hook-like locking member 23 is connected to each of the two lower ends of the chain 12.

As shown in FIGS. 3 and 4, the reduction hoist 5 has a drive shaft in which a wheel shaft 8, an eccentric cam 9, and the socket 10 are integrally connected to the front and rear surfaces of the case 6. 7 is pivotally supported, and the foil shaft 8 inside the case 6
Chain foil 11 on which the chain 12 is wound around
Loosely fit the rotation regulating plate 1 onto the eccentric cam 9 inside the case.
3 is fixed to the side end surface of the chain wheel 11, and the planetary gear 14 of the external gear meshes with the sun gear 15 of the internal gear formed on the side end surface of the chain wheel 11. The rotation of the planetary gear 14 is regulated by the regulation plate 13 . When the handle 24 is connected to the socket 10 of the drive shaft and rotates in the normal direction, the normal rotation of the drive shaft 7 causes the planetary gear train 1 for deceleration.
4, 15, the chain wheel 11 decelerates and rotates normally, and both locking tools 23, 2 connected to the ends of the chain 12
3 is rolled up. When the handle 24 connected to the socket 10 is reversed, the chain foil 11 is reversed and both locking devices 23 are rewound.

When using the device of this example, as shown in FIG. 1, the machine frame 1 with the reduction hoist 5 is placed in a position that straddles the manhole cover 31 that is tightly fitted into the manhole frame 34 buried in the ground. Both locking tools 23, 23 connected to the lower end of the hanging chain 12 of the reduction hoist 5,
The hook-shaped tip of each is attached to the manhole cover 3.
1, the opening locking parts 32, 33 of the manhole cover 31 are hooked onto the pin 23 suspended in the recess 32 on the top surface of the manhole cover 31.
to be locked. Next, the engagement tip of the handle 24 is passed through the handle insertion hole 17 of the handle guide plate and engaged with the socket 10 of the deceleration hoisting machine, and the handle 24 is rotated in the normal direction to hoist the deceleration hoisting machine 5. As a result of the operation, the chain 12 is hoisted and tensed to be pulled toward the manhole cover 31, and the helical spring 22 is compressed. When the upward force is applied to the manhole cover 31 due to the compression of the helical spring 22, the handle 24 is turned upward. Stop rotation operation. After applying a lifting force to the manhole cover 31, an impact is applied to the manhole cover 31 by hitting it with a mallet or the like. Then, the connection between the manhole cover 31 and the manhole frame 34 is loosened by the impact, and the manhole cover 31 flies up from the manhole frame 34 and opens due to the stretching force of the compressed helical spring 22. After the manhole cover 31 is lifted from the manhole frame 34 on the ground, the manhole cover 31
The manhole cover 31 is carried out from a position above the manhole frame 34 by moving the machine frame 1 with the reduction hoist 5 hanging thereon.

As described above, the device of this example can easily open a manhole cover.

In the embodiment shown above, the locking tool 23 connected to the lower end of the chain 12 of the reduction hoist 5 is such that the opening locking portion of the manhole cover hooks the pin 33 into the recess 32 on the top surface of the manhole cover 31. However, if the opening locking part of the manhole cover has a different structure, use a hook shape that is suitable for that structure. Make it.

Further, in the illustrated embodiment described above, the spring 22
The deceleration hoisting machine 5 equipped with a locking tool 23 is attached to the machine frame 1 which can move on the ground.
The locking device may be attached to the body of an automobile and suspended to the ground.

[Brief explanation of the drawing]

FIG. 1 is a front view of an apparatus according to an embodiment of the present invention, and FIG. 2 is a longitudinal sectional side view of the same apparatus. Fig. 3 is an enlarged longitudinal cross-sectional view of the reduction hoist of the same device, Fig. 4 is a cross-sectional view taken along line A-A in Fig. 3, and Fig. 5 is a cross-sectional view taken along line B-B in Fig. 4. It is. 5... Reduction hoisting machine, 12... Chain, hoisting traction strip, 22... Spiral spring, 23... Locking tool, 31... Manhole cover, 32, 33... Locking part for opening.

Claims (1)

[Scope of utility model registration request] Attach a locking device to the end of the hoisting traction strip of the deceleration hoisting machine to lock it to the opening locking part of the manhole cover, and install it in the middle of the hoisting traction strip or between the hoisting traction strip and the locking device. A manhole cover opening device characterized in that a spring is interposed therebetween, which deforms when the manhole cover is pulled by a hoisting operation of a deceleration hoist and applies a lifting force to the manhole cover.