Current application is related with a road installing manhole, especially related with an easy installation and height adjustable manhole comprised of four parts.
Most of manhole is comprised of one main steel pipe and one cover. Once the manhole is installed on the street over sewage line and many other facilities for city life, the position of the manhole cover from the base of the pavement or from the outer surface of the huge construction of a sewage line is fixed. However, due to the severe weather conditions such as extreme temperature change and rains, there develop creeks between the manholes and the road surface surrounding them. Those creeks are not only very dangerous for cars and pedestrians passing by the area. Most local authorities spend lots of their budget to cover up those creeks. The best way is to pave the whole road of that area and paint the lines. But, as the pavements are repeated, the surface of the road reaches well above the cover of the manhole. To avoid such situation, road workers must dig out the whole manhole structure and re-install it based on the new surface of the road.
Many kinds of height adjustable manholes and manhole covers are introduced. Most of those height adjustable manholes utilize screw type support and/or male screw threads developed on the outer surface of the inner pipe combined with female screw threads developed on the inner surface of the outer pipe or support.
However, due to the environment of the places where the manholes are located, it is not an easy procedure to install and re-adjust the height of those screw shape manholes. First of all, the workers must align both of the male and female threads in correct position, engage them and turn the manhole pipe to the desired position. Contaminants, such as sand and metal can stuck between the screw threads make it hard to turn the manhole pipe. Once a manhole is installed on the road, it usually takes at least from couple of months to many years. The moistures from the under ground water and surface water easily corrodes the screw threads and make them stick together. Then it needs extra effort to eliminate the corrodes from the threads.
It is purpose of the current application to provide a manhole that can adjust a height from the cover to the road surface without not only digging out the whole structure from the place where it was buried, but also without extra effort of turning the inner manhole until the desired position is reached. The structure of the manhole of current application enables an easy installation and easy adjustment of the height of the manhole cover from the basin structure of sewage treatment system buried underground.
U.S. Pat. No. 6,698,973 and 6,179,518 to Suatac illustrates an adjustable manhole cover frame assembly suitable for mounting on a manhole basin upper section has an outer ring, capable of resting on the top surface of the upper section, and an inner ring engaging the outer ring by screw threads and having support for a manhole cover. It is like screw cap.
U.S. Pat. No. 6,311,433 to Zdroik illustrates an adjustable manhole/catch basin structure includes a mounting base, adjustable tube, and protection sleeve. The adjustable manhole (1) is installable only onto a concrete lateral (100) by fixing the position with mortar (102).
U.S. Pat. No. 5,095,667 to Ryan, et al. illustrates a telescopic manhole or storm drain installation includes a riser assembly provided with an upper section and adjacent lower section the former of which comprises a side wall defining an inverted frustoconical configuration while the latter provides a vertically disposed member having external threads cooperating with a stationary threaded collar.
U.S. Pat. No. 4,075,796 to Cuozzo illustrates a manhole consists primarily of a cast and internally threaded main body, which receives a cast and internally threaded sleeve, which may be raised to different pavement levels by means of a removable spanner wrench. It includes a pair of diametrically opposed and slidable locking plates, which have pin means on the underside for being received within openings on the upper interior of the sleeve, and the upper portion of the plates projects outwards of the sleeve, so as to lock the sleeve and cover within the main body, thus preventing rotation thereof, the plates when the sleeve is lowered or elevated, serving as a means of rendering the sleeve and cover stationary at various pavement levels.
U.S. Pat. No. 3,629,981 to Mc Caffery illustrates an adjustable height assembly for supporting a cover over a subterranean access opening wherein a cylindrical frame structure having interior coaxial acme threads is adopted to be permanently located in non-rotatable submerged position.
U.S. Pat. No. 3,533,199 to Pickett illustrates a manhole structure comprising a first substantially cylindrical frame member adapted to be disposed underground structure and a second substantially cylindrical frame member adjustably and telecopy disposed with respect to the first frame member adapted to extend upwardly an adjustable distance to the surface of the ground.
None of the prior art teaches to provide a height adjustable manhole system that enables an easy installation and height adjustment without utilizing screw threads system shown in the present application.
The manhole of current application is comprised of an outer-manhole pipe, an inner-manhole pie, a manhole cover, and a support pipe. Three concave arc band shape blades are horizontally located along the inner surface of the outer-manhole pipe in one layer. Five layers of concave arc shape blades, placed with same distance, are aligned to form three vertical columns of blades. Three convex arc band shape blades are horizontally located along the outer surface of the inner manhole pipe. Five layers of convex arc shape blades, placed with same distance, are aligned to form three vertical columns of blades. Size of all the arc band blades is the same. The size of the space between the two neighboring concave blades is the same as the size of a convex blade. When a space between the two neighboring concave blade is occupied by a convex blade, the inner-manhole pipe can move vertically freely. Once a desired vertical position of the inner-manhole pipe is reached, workers turn the inner-manhole pipe horizontally 60 degrees and put down the pipe. Then the concave and convex arc shape blades overlap each other. To separate the two pipes, lift up the inner-pipe slightly, turn 60 degrees horizontally and pull up the inner-pipe. The support pipe is engaged between the top flange of the inner-manhole pipe and top end of the outer manhole pipe to hold and support the distance between them. The structure of the manhole of current application enables an easy installation and easy adjustment of the height of the manhole cover from the basin structure of sewage treatment system.
To close the manhole cover (4), a worker picks up the handle (10) in up right position to the cover (4) and insert the cam shaft (9) through the opening (8). Turn the cover 90 degrees horizontally to move the cam shaft (9), which is now located under the cover (4), to a position perpendicular to the opening (9). Press down the handle (10) into the cam lock box (13). Then the cam shaft (9) moves up ward in the cam hole (11) and lock the manhole cover (4) by adhering the shaft (9) to the underneath side of the flange (7). Rubber packing may be installed between the manhole cover (4) and the flange (7).
Each blade (18) is located with same space (19) from the neighboring blade. The size and shape of the space (19) between the neighboring concave arc shape blades (18) are same as the blade. Three to five layers of concave arc shape blades (18), placed with same space (19), are aligned to form three vertical columns (20) of concave arc shape blades. The size of the space (19) between the two neighboring concave blades (18) is the same as the size of a convex blade. When a space between the two neighboring concave blade (18) is occupied by a convex blade (14), the inner-manhole pipe can move vertically freely. A flange (21) with pluralities of flange holes (22) is developed at the middle of the outer-manhole pipe (2) along the outer surface thereof to fix the pipe to the ground or to a structure underneath of the manhole (1).
When a worker installs a manhole, he/she aligns the blades of the inner-manhole pipe (3) and outer-manhole pipe (2) to be positioned in sequence on an imaginary circular plane that is parallel to the horizontal surface. Then push down the inner-manhole pipe (3) to the depth of desired and rotate the inner-manhole pipe 60 degrees horizontally. The grooves (18-1) developed on the concave arc band shape blades (18) guide the protrusions (14-1) to rotate steadily in a circular motion. In this position, the concave arc band shape blade (18) and convex arc shape band blades (14) overlap each other. The protrusions (14-1) and the dimples (18-2) meet. Push down the inner-manhole pipe (3) to engage the protrusions (14-1) to the dimples (18-2).
The noble structure of the height adjustable manhole comprised of four major part of the current application an easy installation and height adjustment of a manhole buried on a road surface. Many kind of variation is possible based on this disclosure.