JPH069252Y2 - Tubular formwork for box removal - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to a tubular formwork for removing a box which is applied to a joint between a manhole body and a pipe, a duct penetrating portion in construction work, and the like.

(Conventional technology) Manhole in sewage works is crushed by foundation stone (a)
After the foundation concrete (b) is placed on the top, the formwork of the required dimensions is assembled, and the frame concrete (c) is placed and constructed.

The manhole skeletons are installed at the meeting point of the sewer pipe and at a ratio of 1 to 30 to 40m, but there is an inflow pipe (d) and an outflow pipe (d). At that time, it is necessary to open the box in a circular shape.

In order to remove this box, the following methods have been conventionally used.

i) A method in which styrofoam is packed, concrete is poured, and the concrete is cured and then removed.

) A method in which hard corrugated cardboard or sandbags are filled with sand, concrete is poured, and the concrete is cured and then removed.

) A method of placing concrete with a veneer board to secure a gap.

(Problems to be solved by the invention) However, the first method has a problem in fixing the Styrofoam, and when concrete is poured, it floats or easily moves. In addition, it is easily damaged and does not have the desired shape.

Further, in the second method, it is difficult to fix the corrugated board, and there is the same problem as in the first method. Also, sandbags filled with sand do not become round, and concrete scrubbing work is required later.

Furthermore, in the third method, it takes time to process and fix the veneer plate.

A method of constructing a manhole frame after first constructing a pipe is also conceivable, but this method is not a good idea because it causes a problem in assembling the outer mold.

The present invention has been proposed in view of the above problems of the prior art, and the purpose thereof is to make it possible to easily and accurately form a perfect circular void at a predetermined position of a concrete structure. The point is to provide a tubular formwork for unboxing that does not require extra concrete scrubbing work.

(Means for Solving the Problems) In order to achieve the above-mentioned object, the tubular formwork for box extraction according to the present invention is directed in the diametrical direction on the facing surfaces of a pair of semicircular formwork that face each other in the diametrical direction. A turnbuckle is screwed over the threaded rod, and between the two ends of the semicircular form frames adjacent to each other in the circumferential direction, a pair of convex molds connected via a turnbuckle. The outer peripheral projections of the metal fitting are fitted together, and a locking metal fitting that engages and disengages with the convex metal fitting is mounted on the inner peripheral surface of each of the semicircular molds.

(Operation) Since the present invention is configured as described above, it is screwed over the diametrically oriented threaded rods that are respectively diametrically oriented on the facing surfaces of the pair of semicircular molds facing each other in the diametrical direction. By screwing the turnbuckle, the two semicircular molds are separated from each other in the diametrical direction and brought close to each other, thereby assembling a circular mold having a required diameter by the both semicircular molds, while, A semi-circular mold which operates a turnbuckle interposed between a pair of convex metal parts to adjust the diametrical position of the both convex metal parts, and which adjoins the respective outer peripheral protrusions of the convex metal parts. By fitting the locking metal fittings fitted in the gaps between the both end portions of the same and mounted on the inner peripheral surface of the respective semicircular molds to the convex metal fittings, the convex metal fittings are adjacent to each other. It is fixed between two semicircular molds and a perfect circular mold having a required diameter is assembled.

Concrete is cast on the outer periphery of the formwork constructed in this way, and after the cast concrete is hardened, the locking by the locking hardware of the pair of convex hardware is released, and the turnbuckle is operated. Move the convex metal parts close to each other, remove them from the gap between adjacent semi-circular molds, and screw the turnbuckles screwed on the rods of both semi-circular molds to bring both molds close to each other. Both molds are demolded to form a perfect circular void in the cast concrete.

(Embodiment) The present invention will be described below with reference to the illustrated embodiment.

(1) is a pair of semicircular formwork facing each other in the diametrical direction.Screw rods (2) extending in the diametrical direction are planted on the opposing surfaces, respectively, and screw rods (2) of one semicircular formwork (1) are ) Is screwed with a turnbuckle (3).

(4) is a convex metal piece having a protruding portion (4a) arranged on the outer side surface, and a screw rod (5) is planted on the inner surface of the opposite convex metal piece (4), and is attached to the opposite screw rod (5). A turnbuckle (6) is screwed across.

Further, in the vicinity of both ends of each of the semi-circular molds (1), there are L-shaped locking metal fittings (7) for engaging and disengaging with the convex metal fitting (4) as described later.
It is rotatably mounted via (8).

Thus, the two semicircular molds (1) are diametrically opposed to each other, the turnbuckle (3) is screwed onto the threaded rod (2) of the same mold (1), and the turnbuckle (3) is attached. Adjusting by screwing the pair of semi-circular formwork (1)
By assembling a circular formwork having a required diameter to the pipe connection between the manhole inner formwork (A) and the outer formwork (B), the outer projections of the opposing pair of convex metal fittings (4) (4a) is fitted into the gap between the adjacent semicircular molds (1), and the turnbuckle (6) is operated to move the convex metal parts (4) to adjacent semicircular molds. Tightly fit it in the gap of the frame (1), rotate the locking metal fitting (7) around the pin (8) to lock the convex metal piece (4), and thus the inner and outer molds (A ) Assemble a perfect circular formwork with the required diameter between (B).

Thus, the manhole skeleton concrete is cast between the inner and outer molds (A) and (B), and after the cast concrete is hardened, the locking metal fitting (7) is rotated to form a convex metal object (4). , The turnbuckle (6) is screwed to draw the biconvex metal fittings (4) toward each other, and disengage from the gap between the adjacent semicircular molds (1),
The turnbuckle (3) is screwed to draw both of the semicircular molds (1) and the mold is removed to form a circular pipe connection space in the manhole body.

(Effects of the Invention) As described above, in the tubular formwork for removing a box according to the present invention, screw rods are planted in diametrical directions on opposite surfaces of a pair of semicircular formwork that face each other in the diametrical direction. While screwing a turnbuckle on each screw rod, the turnbuckle is interposed on a pair of convex metal fittings having an outer protruding portion fitted between the respective end portions of the semicircular molds adjacent to each other in the circumferential direction, By constructing the convex metal fitting to engage and disengage the locking metal fitting mounted on the inner peripheral surface of each of the semicircular molds, a perfect circular box removing mold having a required diameter can be obtained. It can be assembled, there is no fear of moving during concrete pouring, and it can be easily fixed by making it according to the thickness of the pouring concrete.

Further, according to the present invention, a perfect circle is removed from the box, so that it is not necessary to scrub concrete or the like afterwards.

Furthermore, the formwork of the present invention is easy to disassemble and can be reused again.

[Brief description of drawings]

FIG. 1 is a perspective view showing an assembled state of the tubular formwork for removing a box according to the present invention, FIG. 2 is an exploded perspective view thereof, FIG. 3 is a front view showing its used state, FIGS. 4 and 5 Are the arrows in Fig. 3, respectively
IV-IV view as well as arrow V-V view, FIG. 6 is a plan view showing the joint portion of the semi-circular form, and FIGS. 7 and 8 are plan views and front views, respectively, of the locking hardware. FIG. 9 and FIG. 10 are plan views as well as a longitudinal sectional view of the manhole. (1) …… Semi-circular form, (2) …… Screw rod (3) …… Turnbuckle, (4) …… Convex metal object (4a) …… Outside protrusion, (6) …… Turnbuckle

Claims (1)

[Scope of utility model registration request] 1. A turnbuckle is screwed over screw rods which are diametrically oriented and erected on the facing surfaces of a pair of semicircular molds facing each other in the diametrical direction, and are adjacent to each other in the circumferential direction. Between each end of each of the semi-circular molds, the outer peripheral protrusions of the one pair of convex metal fittings connected via a turnbuckle are fitted, and a locking metal fitting that engages and disengages the convex metal fittings is provided. A tubular formwork for removing a box, which is mounted on the inner peripheral surface of each of the semicircular formwork.