JPS5924715Y2 - Locking device for manhole covers in septic tanks, etc. - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a locking device for a manhole cover that covers a manhole in a septic tank for treating sewage.

The septic tank has a manhole on its top side that serves as a cleaning opening, and a manhole cover that can be removed by holding the handle and pulling it up is usually inserted into the manhole.

The manhole cover of this septic tank is laid so that it is exposed on the ground surface when the septic tank is buried underground.
Particularly in domestic septic tanks, children may be bothered to open them, and there is a risk of the child falling into the septic tank through the manhole being opened. It is desirable to keep it locked to prevent it from happening.

Some common manhole covers are equipped with locking devices, but they are troublesome to assemble to the manhole cover, and furthermore, there is a problem that they rust due to moisture and become immovable.

An object of the present invention is to provide a locking device that can be easily assembled to a manhole cover provided in a manhole of a septic tank and that will not rust and become immovable.

Next, a locking device for a manhole cover in a septic tank according to the present invention for achieving this purpose will be described in detail with reference to an illustrative embodiment.

In Fig. 1, 1 is a septic tank main body, only a part of which is shown in the drawing, and is a conventionally known type of septic tank that treats wastewater using a separation chamber and an aeration chamber (none of which are shown) provided inside. , a manhole 1 is provided on the upper surface of the frame for cleaning and inspecting the separation chamber and aeration chamber installed inside.
A cylindrical manhole frame 10 having a shape 0a (FIG. 2) formed inside the body is shaped so as to rise short upwards.
A ring-shaped entrance frame 2, which is made in combination with a manhole cover 3, is attached to the opening at the upper end of the manhole frame 10.

The ring-shaped entrance frame 2 is made of a material different from the septic tank main body 1 and the manhole frame 10 that is integrally continuous therewith, and the outer periphery of the bottom side of the septic tank main body 1 is formed into When burying, as shown in Figure 2, it is fixed integrally to the upper surface of the opening at the upper end of the manhole frame 10 with set bolts 20, or a mounting flange 21 is provided for fixing it together with cement. .

Further, on the inner circumferential side of the ring-shaped entrance frame 2, the inner circumferential surface 2a thereof is formed into a tapered surface whose diameter decreases downward, and a manhole cover that is dropped into the ring-shaped entrance frame 2 is formed. An annular support shelf 22 that extends inward to support 3.
At the projecting end of the support shelf section 22, there is further a retaining stage projecting in a ring shape toward the center of the entrance frame 2 at a position elevated from the bottom surface of the entrance frame 2. Part 22
A is the shape.

The manhole cover 3 is made of the same material as the ring-shaped entrance frame 2 described above, and is provided with a tongue-shaped peripheral wall that protrudes downward on the bottom side so that the side cross section has a downward U-shape. It is formed into a shape.

The diameter of the manhole cover 3 is slightly smaller than the inner diameter of the tapered inner peripheral surface 2a of the ring-shaped entrance frame 2.

Further, the outer circumferential surface 3a of the manhole cover 3 is formed into a tapered surface corresponding to the inner circumferential surface 2a of the manhole frame 2.

Furthermore, a grip portion 33.33 is provided on the top surface.

Furthermore, on the peripheral edge of the manhole cover 3, a locking body 4, which will be described later, is attached at a portion that overlaps vertically with the retaining step 22a provided on the artificial frame 2, as shown in FIG. The hole 34.34 is formed as a through hole whose diameter gradually decreases downward as shown in FIG.

Reference numeral 4 denotes a locking body for locking the manhole cover 3 which has fallen into the ring-shaped entrance frame 2 so that it does not open easily.

The lock body 4 is made of a synthetic resin material and includes a cone-shaped head 40 whose diameter decreases downward so as to fit into the mounting hole 34, and a cylindrical shape with a hollow lower half, and a lower peripheral edge of the head 40. An engaging flange 44 protruding from the center in the circumferential direction, an axial rod portion 43 hanging from the center of the bottom surface of the head 40, and an engaging arm 42 extending laterally from the lower end of the axial rod portion 43. A notch groove 45 is provided on the outer peripheral surface of the hollow lower half of the head 40 to facilitate expansion and contraction of the lower half. Further, the upper surface of the head 40 is provided with an engagement groove 41 for engaging a tool for rotational operation.

Therefore, the lock body 4 made of this molded piece of synthetic resin material
The assembly into the mounting hole 34 provided in the manhole cover 3 described above is carried out by press-fitting into the mounting hole 34 from above.

By press-fitting into the mounting hole 34, the lower half of the hollow cylindrical head 40 of the lock body 4 is bent and reduced in diameter, and the engagement collar 44 at the lower end of the head 40 is inserted into the mounting hole 34. When the manhole cover 3 is pulled out downward, the diameter expands and returns to its original state, and the engaging collar 44 engages with the lower surface of the manhole cover 3 to prevent the manhole cover 3 from coming out, completing the assembly.

The lock body 4 assembled to the manhole cover 3 in this way is in a state where the cone-shaped head 40 is only fitted into the cone-shaped attachment hole 34, so the attachment hole 34, and by rotating the head 40, the engagement arm 42 provided at the lower end of the shaft portion 43 hanging from the center of the bottom surface of the head 40 engages the manhole entrance frame 2. The upper surface 42 of the engaging arm 42 enters the lower surface side of the engaging step 22a provided on the inner circumferential surface, and when the manhole cover 3 is opened due to a child's mischief, the upper surface 42 of the engaging arm 42
a butts against the lower surface of the engagement step 22a, preventing the manhole cover 3 from opening and locking it in the closed state.

Next, to explain the function and effect, the locking device for a manhole cover in a septic tank according to the present invention, which is configured as described above, has an attachment hole 3 of a lock body 4 provided in a manhole cover 3.
4 has a cone shape whose diameter decreases downward, and the lock body 4 attached to this is made of a synthetic resin material and has a cone-shaped head 40 whose lower half is hollow and cylindrical, and the head. An engaging flange 44 provided at the lower end of the head 40, an axial rod portion 43 hanging down from the center of the bottom surface of the head 40, and an engaging arm 42 provided at the lower end of the axial rod portion 43 are integrally continuous. Since it is a molded piece and can be assembled by press-fitting it into the mounting hole 34 from above, the manhole cover 3
In addition, in the assembled state, the engaging arm 42 for locking the manhole cover 3 to the manhole entrance frame 2 and the head for rotating it to the locking position are provided. Since all the parts such as the part 40 are continuous as one body and are made of resin material, even if rainwater and dirt in the septic tank body 1 are washed away, it will not function properly due to rust or corrosion. Furthermore, the engagement step 22a provided at the projecting end of the support shelf 22 serves as an engagement surface for the engagement arm 42, as shown in FIG. Since a margin can be formed between the upper surface 42a of the upper surface 42a and the lower surface of the engagement step part 22a which is the engagement surface on the entrance frame 2 side, mud, dirt, etc. can be prevented from adhering to the inner peripheral surface of the entrance frame 2. Locking and unlocking can always be performed reliably and easily.

[Brief explanation of the drawing]

Fig. 1 is a perspective view of the manhole cover dropped into the manhole entrance frame of the septic tank and covered, Fig. 2 is a cross-sectional view showing the manhole cover in a locked state, and Fig. 3 is a bottom view of the same as above.
FIG. 4 is a cutaway side view of the manhole cover in an unlocked state, and FIG. 5 is a perspective view of the lock body. Explanation of drawing symbols, 1... Septic tank body, 2...
... Entrance frame, 3... Manhole cover, 4...
... Lock body, 10 ... Manhole frame, 20
...Set bolt, 21...Mounting flange, 22...Support shelf, 22 a...
・Engagement step part, 33... Handle part of manhole cover,
34...Mounting hole, 40...Head of lock body, 41...Engagement groove, 42...Engagement arm, 42 a... ...Top surface of engagement arm, 43
...Shaft rod portion, 44...Engagement flange, 45.
...Notch groove, 10a...Manhole.

Claims (1)

[Scope of utility model registration request] The manhole inlet frame 2 installed at the upper end of the manhole frame 10 erected on the top side of the septic tank body 1 is connected to the septic tank body 1.
Separately, it is shaped like a ring, and on the inner circumference of population frame 2,
A support shelf 22 is formed in an annular shape and projects inward to support the outer peripheral edge of the manhole cover 3 that is inserted into the entrance frame 2. An engaging stepped portion 22a is provided that extends inward in a jing-like shape,
At the peripheral edge of the manhole cover 3, a mounting hole 3 whose diameter decreases downward is provided at a portion that overlaps the above-mentioned retaining step portion 22a above and below.
4, and the mounting hole 34 has a cone-shaped head 40 made of a synthetic resin material and a cylindrical shape with a hollow lower half that fits into the mounting hole 34, and an outer circumference from the lower end periphery of the head 40. An engagement collar 44 that projects in the direction, a shaft portion 43 that hangs down from the center of the bottom surface of the head portion 40, and a retaining arm 42 that projects laterally from the shaft portion 43 are integrally continuous. A molded plug-shaped lock body 4 is press-fitted and rotatably locked by the engagement flange 44 of the lock body 4, and as the lock body 4 rotates, the upper surface 42a of the engagement arm 42 A locking device for a manhole cover in a septic tank, characterized in that the locking device for a manhole cover in a septic tank is configured such that the lower surface of the engaging stepped portion 22a of the inlet frame 2 is engaged with the lower surface of the engaging step portion 22a of the inlet frame 2 in a freely engaging and detachable manner.