JPH0316885B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application of the Invention The present invention relates to an inner mold for a formwork for mass producing concrete products such as pipes, boxes, and box culverts.

BACKGROUND TECHNOLOGY In general, formwork for forming concrete products such as pipes, mounds, box culverts, etc. consists of a substantially box-shaped outer mold with an open top and a substantially cylindrical inner mold disposed inside the box-shaped outer mold. Concrete is filled between the outer and inner molds, and after it has solidified, the outer and inner molds are removed to produce concrete products. The inner mold is usually a wedge-shaped plate 40 called "sashi" as shown in FIG.
Several side plates were connected in a cylindrical shape. Since such demolding and assembly of the inner mold is carried out by pulling out or hammering in the insert, the workability is extremely poor and the inner mold quickly becomes damaged. An attempt was made to improve this by Special Publication No. 53-13485.
The inner mold described in Utility Model Publication No. 59-7051,
It consists of a peripheral wall having a vertical opening, a closing wall that closes this opening, and a means for moving these.The removal of this inner mold involves moving the closing wall and part of the peripheral wall inward (usually called ``squeezing''). ), this is done by creating a gap between the inner mold and the concrete product and then removing the inner mold. At this time, screws or diamond-shaped link mechanisms are usually provided at two locations (upper and lower) as means for moving the closing wall due to the need for parallel movement of the closing wall, and separate screws or the like are used as means for moving part of the surrounding wall. This has been done by providing a link mechanism or by using a link mechanism to link the movement of the blocking wall.

Problems to be Solved by the Invention The above-mentioned closing wall of the inner mold is designed to prevent damage to solidified concrete during demolding, and to prevent deformation of the formwork itself and endure repeated use over a long period of time.
Perfect translation is desirable. However, in conventional internal molds, complete translation of the closing wall has been considered difficult. In other words, movement using screws is actually achieved by alternately rotating the upper and lower screws, and a mechanism in which two upper and lower diamond-shaped link mechanisms are linked with a single bolt is complicated and costly. Furthermore, the play in the multiple pivot points and the threaded portions of the screws combined to result in a large amount of wobbling.

The present invention solves the above-mentioned problems of the conventional inner mold, has a relatively simple structure, realizes complete parallel movement of the closing wall when the inner mold is removed, and at the same time allows partial movement of the peripheral wall. The molds are also linked together to provide an extremely high-performance inner mold that is easy to handle.

Means for Solving the Constituent Problems of the Invention In the present invention, the following measures were taken to solve the above problems. That is, the present invention provides a peripheral wall having a vertical opening, with movable parts on both sides and fixed parts at opposing positions, a closing wall that is movable to close or open the vertical opening, and a peripheral wall that is movable so as to close or open the vertical opening, and and an inner mold which is removed from the mold by moving the closing wall and the peripheral wall moving part inward by the moving means to form a gap between them and the solidified concrete product, wherein each of the peripheral wall moving parts A support member is provided to protrude inwardly from at least two locations above and below, and a rotating rod is pivotally attached to the support member, an arm is fixed to the rotating rod at least at two locations above and below, and the tip of this arm is attached to the This is an inner mold for a formwork for forming a concrete product, which is pivotally attached to a projecting piece protruding from the back surface of a closing wall, and interlocks the peripheral wall moving part and the closing wall.

Function: When the inner mold is removed from the inner mold, when the closing wall is moved inward by the moving means, the arms pivotally attached to the projections on the back of the closing wall are drawn inward while rotating. Since one end of the arm is fixed to the rotating rod, the rotating rod also rotates in the same way as the arm and is pulled inward, and the peripheral wall moving part connected to it via the support member also moves inward at the same time. do. At this time, the arms provided at at least the upper and lower positions rotate at an angle equal to the rotation angle of the rotating rod due to the torsional rigidity of the rotating rod, so the moving distance of the closing wall is equal in both the upper and lower positions. Perfect translation is achieved. Similarly, when moving the closing wall outward, it is also completely translated.

First Embodiment FIGS. 1 to 4 show an inner mold 1 according to a first embodiment of the present invention. FIG. 1 is a plan view with the left upper support member removed, and FIG. 2 is a longitudinal sectional view. , Figure 3 is A
-A sectional view and FIG. 4 are plan views showing the squeezed state with the left upper support member removed.

The inner mold 1 is for manufacturing a concrete pit, and is arranged inside the outer mold 2 as shown in FIGS. 1 and 2. As shown in Fig. 4, the peripheral wall 3 has a vertical opening, with a moving part 3a on both sides, a fixed part 3b opposite the fixed part 3b, and a bent part 3c between the moving part and the fixed part. ing. The moving part 3a is reinforced by a support member 5, and the fixed part 3b is reinforced at the top and bottom by reinforcing members 13, and movement of the moving part 3a is performed by bending the unreinforced bending part 3c. It is reasonable for the support member to also serve as a reinforcing material for the peripheral wall moving portion in this way. The closing wall 4 is made by fitting rubber onto the front surface of a metal plate, and is movable to close or open the longitudinal opening of the peripheral wall 3, as shown in FIG. 1 or 4. A protruding piece 8a is fixed to the upper part, a protruding piece 8b is fixed to the lower part, and two vertical plates 10 are fixed between the upper and lower protruding pieces 8a and 8b. The rubber on the front of the closing wall 4 is used to completely prevent concrete leakage, but the configuration of the closing wall is not limited to this.
It may also be made of iron plates only. The rotating rods 6, one each on the left and right, are vertically pivoted to upper and lower support members 5 that protrude inwardly from the peripheral wall moving portion 3a. As shown in FIG. 3, arms 7 are fixed to each rotating rod 6 at two locations, upper and lower, and the tip of each arm 7 is pivotally attached to a protrusion 8a or 8b with a bolt 11. A diamond-shaped jack 9 serving as a moving means connects a vertical plate 10 on the back side of the closing wall 4 and a reaction member 12 supported by a peripheral wall remote from the vertical opening.

To squeeze the inner mold 1, the bolt 9a is rotated in a predetermined direction to operate the jack 9. Then, the closing wall 4 moves inward, and the arm 7 and the rotating rod 6, which are pivotally attached to the projecting pieces 8a and 8b, move inward while rotating. At this time, since one end of each arm 7 is fixed to the rotating rod 6, the rotation angles of the upper and lower arms are always equal due to the torsional rigidity of the rotating rod, and the closing wall moves completely in parallel. When the rotary rod 6 rotates and moves inward, the support member 5 pivoting on it
And the peripheral wall moving part 3a also moves inward at the same time.
When the squeezing is completed, the state shown in FIG. 4 will be achieved. In the figure, the size of the inner mold before squeezing is shown by a dashed line.

When the bolt 9a is rotated in the opposite direction from the state shown in FIG. 4, the closing plate 4 moves outward in parallel, and at the same time, the peripheral wall moving portion 3a also moves outward. When the outer end of the projecting piece 8a comes into contact with the rotating rod 6, this becomes a stopper, and the outward movement of the closing wall and the peripheral wall moving portion is stopped, returning to the state shown in FIG.

Second Embodiment FIGS. 5 to 8 show an inner mold 20 according to a second embodiment of the present invention, FIG. 5 is a plan view with the left upper support member removed, and FIG. 6 is a B-B 7 is a longitudinal sectional view, and FIG. 8 is a longitudinal sectional view showing a squeezed state.

The inner mold 20 is also for manufacturing a concrete pit, and its configuration is the same as the inner mold 1 of the first embodiment.
is almost the same, but the method of pivoting the rotating rod and the means of moving the closing wall are different.

As shown in FIG. 6, the rotating rod 21 has a cylindrical shape, into which a mandrel 22 is inserted, and the top and bottom of the mandrel 22 are fixed to support members.

A clamp 23 is used as a means for moving the closing wall. The clamp 23 has a prismatic front rod 24.
A rear rod 25 having a U-shaped cross section is connected at a fulcrum q, and the front end of the front rod 24 is connected to a vertical plate 30 on the back side of the blocking wall 29.
The rear end of the rear rod 25 is connected to a protrusion 31 at the center of the reaction member 28 at a fulcrum r. In the clamped state, the q fulcrum is at p, as shown in Figure 7.
Since it is adjusted with the adjustment bolt 27 so that it is located slightly below the straight line connecting the fulcrum and the r fulcrum,
No matter how much inward force is applied to the closing wall, the closing wall will never move inward. rear rod 25 q
A lever 26 is fixed to the side near the fulcrum, and when squeezing the inner mold, insert a long pipe into the lever 26 and use the lever to flip it up around the r fulcrum, as shown in Figure 8. In an instant, the closing wall 29 moves inward in parallel, and the peripheral wall moving part also moves inward.
As in the first embodiment, they simultaneously move inward. To return to the state shown in FIG. 7, if the lever 26 is pushed down in the opposite direction, the closing wall 29 will instantly move outward in parallel, and at the same time the peripheral wall moving section will also move outward. The present embodiment is characterized in that the inner mold can be squeezed and returned with one touch in an extremely short time.

Although both the first and second embodiments show circular inner molds, the inner mold of the present invention is not limited to circular shapes, and may have other shapes.
For example, it can also be applied to quadrilateral or oval shapes.

Effects of the invention The inner mold of the present invention has a relatively simple structure, and
Because the closing wall moves parallel to the complete wall during demolding,
This prevents damage to the solidified concrete and the formwork itself, and requires only one moving means, which was previously provided at two locations, upper and lower. Furthermore, since the peripheral wall moving part moves in conjunction with the closing wall, handling is extremely easy, and the time required for demolding and assembly is short.

[Brief explanation of the drawing]

1 to 4 show a first embodiment of the present invention,
Fig. 1 is a plan view with the left upper support member removed, Fig. 2 is a vertical sectional view, Fig. 3 is a sectional view taken along line A-A, and Fig. 4 shows the left upper support member in the squeezed state. FIG. 5 to 8 show a second embodiment of the present invention, FIG. 5 is a plan view with the left upper support member removed, FIG. 6 is a sectional view taken along line B-B, and FIG. Vertical sectional view, FIG. 8 is a vertical sectional view showing a squeezed state. FIG. 9 is a perspective view of a conventional inner mold. 1...Inner mold, 2...Outer mold, 3...Peripheral wall, 3a...
...Moving part, 3b...Fixed part, 3c...Bending part, 4
...Closing wall, 5... Support member, 6... Rotating rod, 7
...Arm, 8a, 8b...protrusion, 9...jacket,
10...Vertical plate, 12...Reaction force material, 20...Inner mold,
21... Rotating rod, 22... Mandrel, 23... Clamp, 24... Front rod, 25... Rear rod, 26... Lever, 27... Adjustment bolt, 28... Reaction material, 29
...Closing wall, 30...Vertical plate, 31...Protrusion, p,
q, r... fulcrum.

Claims (1)

[Claims] 1. A peripheral wall having a vertical opening, with movable parts on both sides and fixed parts at opposing positions, and a closing wall that is movable to close or open the vertical opening;
and a means for moving the closing wall, and the inner mold is demolded by moving the closing wall and the peripheral wall moving part inward to form a gap with the solidified concrete product, Support members are provided to protrude inward from at least two upper and lower locations of each of the peripheral wall moving parts, and a rotating rod is pivotally attached to the support members,
An arm is fixed to the rotating rod at least in two places, upper and lower, and the tip of the arm is pivotally attached to a protrusion protruding from the back surface of the closing wall, so that the peripheral wall moving part and the closing wall are interlocked. An inner mold for a formwork for forming concrete products, which is characterized by: