JPH0137245B2 - - Google Patents

Description

Detailed Description of the Invention The present invention relates to an instant demolding method and a molding device for concrete products, and involves compressing concrete in molds with different depths depending on the location using a press plate, thereby achieving uniform compression at all locations. In order to achieve the same ratio and porosity, concrete is first poured into the deep part and compressed to level out the depth, and then the whole is filled and rolled down to finish.

The instant demolding method involves putting hardened concrete into a mold, mechanically hardening it through vibration and compression, and immediately taking it out of the mold and sending it to a curing field.Since one mold is used repeatedly, it is similar to the pour-in method. It does not require a large number of molds and is also advantageous in mechanizing each process. Therefore, high productivity is achieved in concrete blocks for civil engineering, which have a relatively simple shape and do not require reinforcing bars.

However, when considering the quality of products produced by this instant demolding, there are some problems. If the product is a cube, applying uniform vibration to the concrete and compressing the entire top surface in the conventional way (although there are technical problems) theoretically would compress the entire product evenly. However, the product shape is rarely cubic, and in many cases molds with different depths are used depending on the location. If we use the conventional method of filling this formwork with concrete and rolling down the top surface with a single press plate, the compressibility of the concrete will theoretically differ from place to place. If concrete in shallow areas has an appropriate compressibility, concrete in deep areas will have insufficient compressibility.

Even if the compression rate is insufficient, there is no problem with immediate demolding because the skin of the product is hammered into the vibrating formwork. However, insufficient compressibility means high porosity and low strength. Concrete is strong only in shallow areas where it has been effectively compressed by the press plate, but if it is weak in locally deeper areas, it will be unreliable and its uses will be limited.

Based on the discovery of this important problem, the purpose of this invention was to create a method and device that would prevent the porosity of concrete from changing significantly, whether deep or shallow in the formwork, and this was achieved.

To briefly explain this invention, as mentioned above, hardened concrete is first supplied to the deep part of the formwork, which has different depths depending on the place, and the upper surface of the concrete is shaken while the formwork is vibrated. The local press plate is used to press the concrete with a pressure within a range that does not impair concrete fluidity due to vibration, and when the press stops, the local press plate is pulled up once or multiple times to approximately equalize the remaining depth of the formwork. This is an immediate demolding method that is characterized by adding concrete to fill the entire formwork, and finishing by rolling it down with a finishing press plate that covers almost the entire opening of the formwork.

Next, with reference to the drawings, the apparatus of the present invention will be explained first, and then the molding method of the present invention will be explained in more detail.

1 to 4 show an embodiment of the present invention, which is intended for the simplest form of concrete block B (FIG. 5). The main parts are a formwork 1 whose depth varies depending on the location, a vibration device for the formwork 1, in this case an eccentric rotary body 2 attached to the formwork 1, a motor 2a that drives this with a belt, and an instant demolding device. As shown in Fig. 4, there is a lifting frame 4 which lowers the pallet 3 which is the bottom plate of the formwork 1 and transfers it to the unillustrated unloading device, and locally transfers the hardened concrete to the deep part 1a of the formwork 1. There is a concrete supply device that can supply the required amount to the mold and then fill the entire formwork 1. In this case, a conventional fixed concrete hopper 5 and a sliding hopper 6 for transferring the concrete in one batch to the receiving form 1 and dropping it are used. First, in order to locally drop the material into the deep part 1a at the center of the formwork 1, a quantitative hopper with a shutter 6a, which is patented by the present applicant (Japanese Patent Publication No. 53-13450), is used. Pull it backwards. Although not shown, the shutter 6a is pulled out and returned to the rear by a pneumatic cylinder attached to the rear of the sliding hopper 6. An inner frame 20 is fitted into the formwork 1 only at the beginning, and an appropriate amount of concrete is received in the central part.

The compression press device, which is an important feature of the present invention, includes a local press plate 7 that presses only the concrete supplied into the deep part 1a of the form 1, a finishing press plate 8 that covers almost the entire opening of the form 1, Both press plates 7 and 8 have dodging mechanisms that can operate without any trouble. As a dodging mechanism, this embodiment does not replace both press plates, but after the deep press plate 7 has fulfilled its role, it rises to fit into the recess on the lower surface of the finishing press plate 8 and is incorporated as a part thereof. ing. The dodging mechanism in the embodiments described below is
Both press plates 7 and 8 are exchanged along the dovetail groove on the lower surface of the slide of the press.

The formwork (side wall) 1 is a formwork support frame 1 fixed at an appropriate height of the left and right supports and press guides 9 that stand on the floor.
0 via a cushioning material (not shown). Since this embodiment uses the applicant's latest molding machine that can respond to the diversification of products, it has a somewhat special structure, but the press frame 11 that goes up and down along the above-mentioned support 9 is located on the left and right sides of the upper surface of the lifting frame 4 for demolding. is driven by a hydraulic cylinder 12. Cushioning material 1 is placed on the bottom surface of the press frame 11.
3, the upper structure 8a of the finishing press plate 8 is fixed, and a hydraulic cylinder 14 for pressing down the local press plate 7 is also attached. Further, the lower surface of the finishing press plate 8 has a recess for receiving the local press plate 7 and aligning the lower surfaces of the two, and a hole is made in the center of the recess through which the piston rod of the cylinder 14 for the local press plate 7 passes, and a hole is made on the left and right sides of the recess. Holes for left and right guide rods 15 extending upward from the local press plate 7 are also made.
A guide tube 16 is fixed to the upper edge of the hole.

The demolding lifting frame 4 is driven by left and right lifting cylinders 17, and supports the lower surface of the pallet 3, which serves as the bottom plate of the mold 1, via a support material 18 and a cushioning material 13. An eccentric rotating body 19 of a vibrating device is also attached to the lower surface of the receiving member 18, and is driven by a motor (not shown).

In order to carry out the molding method of the present invention using this device, the formwork support frame 10 is fixed in advance to an appropriate height of the support column 9, the side walls of the formwork 1 are attached to this, and the pallet 3 which becomes the bottom plate is received. The pallet 3 is placed on the material 18, and the lifting frame 4 is raised to park the pallet 3 at the bottom plate of the formwork 1 as shown in FIG.

After completing the preparation of the formwork 1 in this way, the sliding hopper 6 below the stationary hopper 5
Move it onto formwork 1. As described above, this sliding hopper 6 is equipped with a shutter 6a, and the inner frame 20 is fitted only when concrete is initially supplied. Therefore,
When the shutter 6a is pulled out, an appropriate amount of concrete C fills the deep part 1a of the formwork 1. The appropriate amount varies depending on the shape of the deep part of the formwork; if the shape is easy to push, the deep part should be filled in one time, and if the shape is difficult to push, the amount should be filled in several times.

As shown in FIG. 1, in the case of a simple formwork 1, it is fed in a slightly heaped form so as to fill the deep part 1a in one go, and as shown in FIG. When it is rolled down with pressure, it should be at the same height as the bottom of the shallow part. If the deep part 1a of the formwork has an additional recess at its bottom,
First, fill the dent with concrete, compress it with a local press board that fits the dent, and then
This will fill in the entire area a.

Now, in the illustrated embodiment, when concrete has been poured into the sliding hopper 6, the shutter 6a is closed again, the inner frame 20 is removed, and the sliding hopper 6 is returned under the stationary hopper 5. Then, as shown in FIG. 2, the fluid pressure cylinder 14 is driven to lower the local press plate 7, and the concrete C in the deep portion 1a is rolled down. The pressing force is set to a level that does not impair the fluidity of the concrete due to vibration, and since the concrete is compressed by the amount that the voids are reduced, the completion of compression can be determined by the stagnation of the local press plate 7 in pushing. Instead of pulling back the local press plate 7 after waiting for it to stagnate, it is also possible to experimentally determine the pushing distance to the point of stagnation and then pull it up when that distance is reached.

In the conventional instant demolding molding apparatus, the flattest surface of the product is placed on the upper surface (open surface) of the mold, and the product is pressed down by a press plate that covers the entire upper surface, similar to the finishing press plate of the present invention. The pressing process is carried out with the idea of compacting hardened concrete with low viscosity so that it can be demolded immediately. Especially in the case of machi blocks, the upper surface becomes the block surface, so it is thought that the higher the pressing pressure, the better. ing.

Unlike the concept of compacting concrete with the strong pressure of a press plate, the local press plate 7 of the present invention sufficiently accelerates the speed at which the hardened concrete, which has increased fluidity through vibration, settles under its own weight and becomes densified. Therefore, it is pushed in with a pressure within a range that does not impair its fluidity. The fluidity (activity) of hard-mixed concrete (aggregate) is caused by vibration, and there is no need for pressure to kill the vibration and break up the aggregate. Compressing hardened concrete means arranging the aggregates well to reduce voids and, as a result, reducing the volume.

In this way, once or multiple steps of filling the deep part 1a of the formwork with compressed concrete have been completed, and when the remaining depth of the formwork 1 is approximately equalized, additional concrete is supplied and the formwork 1 is filled with compressed concrete. satisfy the whole. All that is required is to remove the inner frame 20 and move the sliding hopper 6, which has been waiting under the stationary hopper 5, onto the formwork 1.

The concrete filling the formwork 1 is pressurized by a finishing press plate 8. At this time, the sliding hopper 6 may be returned to the bottom of the stationary hopper 5, but it is recommended to leave it directly above the formwork 1, finish the finishing press, fit the inner frame 20, and return it to the stationary hopper 5. Ru.

The finishing press plate 8 is lowered together with the press plate 11 by the hydraulic cylinder 12, and the entire upper surface of the concrete in the formwork is rolled down. The pressure per concrete unit area may be the same as that for the local press plate 7, but may be increased somewhat if the upper surface is the product surface. In principle, the concrete compressibility and porosity of the deep part 1a of the formwork, which has already been compressed, and the shallow part 1b, which is compressed by the finishing press board 8, are the same. The pressure of the finishing press plate 8 also has the effect of strengthening the concrete joint of both the deep and shallow parts 1a, 1b. Note that the local press plate 7 fits into the lower surface of the finishing press plate 8 and takes part in the finishing press process, but if unevenness on the product surface (open surface of the formwork) is permitted, unevenness may be provided on the lower surface of the local press plate 7. ,
It is also good to make it easier to connect the upper surface of the concrete in the deep portion 1a to the additional concrete.

After finishing the finishing press process in the state shown in Fig. 3, the press plate 11 is raised as shown in Fig. 4, the elevating frame 4 for demolding is lowered, the product B is taken out together with the pallet 3, and transferred to a conveying device (not shown), and a new one is taken out. It receives pallet 3.

Although the embodiments for block B, which belongs to the simplest category, have been explained above, since this invention is intended for formworks having different depths depending on the location,
Its application range is wide. For example, in the case of a formwork 1' for a product that has flanges on both the upper and lower surfaces as shown in Figures 6 and 7,
In the upper half, the depth gradually increases toward the center, and the tapered center widens in the lower half. It is troublesome to locally fill the formwork with concrete so that the depth of the formwork is even, so in this case, consider the upper half of formwork 1' to be the shallow part and the lower half to be the deep part. After compressing the lower half of the concrete as shown in Figure 6, finishing pressing was performed as shown in Figure 7. Although the depth of the upper half is different, there is no sudden step, so there is little impact.

The embodiments shown in FIGS. 8 and 9 are for molding U-shaped members with reinforcing bars, which have not conventionally been subject to the instant demolding method. As shown in the figure, for the inner width of 240 mm or less, there are few vertical bars 21, so the concrete C, which is put into deep parts on both sides by U-shaped local press plates 7' with dodging grooves 25 where they hit the horizontal bars 22, is It can be compressed as shown in the figure.

This groove-shaped local press plate 7' is fitted into the dovetail-shaped sliding part of the slide-side mounting plate 23 of the press machine, and serves as a dodging mechanism to be replaced with the finishing press plate 8' shown in Fig. 9 after the mission is completed. There is.

It should be noted that, not limited to this embodiment, the local press plate that compresses the concrete in the deep part of the formwork does not have to press the entire upper surface of the concrete. In the embodiment shown in FIGS. 8 and 9, the horizontal strip 22
The upper surface of the nearby concrete is not pressurized. However, even if the top surface of the concrete is pressurized intermittently,
Since the pressure spreads out in a conical shape, it is possible to obtain a compression effect close to that of applying pressure to the entire surface. The pressing force of the local press plate 7 shown in FIG. 6 spreads downward, and also in the lateral direction due to the presence of the bottom surface of the mold. Therefore, the narrow press plate 7 can exert a compression effect on a large volume despite the relatively small pushing amount. From this, at the entrance to the deep part of the formwork,
It is not difficult to design a local press plate, which is pressed into the concrete by a few percent of its depth, in a shape and arrangement that avoids the vertical and horizontal lines of various products.

The pressing direction of the local press plate is not limited to downward, but should be an appropriate direction depending on the shape of the product. The embodiment shown in FIG. 10 is an example in which the bottom concrete C, which is difficult to apply pressure from above, is compressed by a second local press plate 7a that fits and slides into a side opening 24 provided in the side wall of the form. This second local press plate 7
When pouring concrete, a is pushed outward by the amount planned to be pushed in, and once the concrete is in, it is pushed through the buffer joint 26 at the same time as the local press plate 7 above.

Above, the indentation amount of the local press plate was written as several percent of the concrete depth, but the indentation amount is due to the volume reduction due to the reduction of voids in hardened concrete. For example, assume that the concrete C filling the deep part 1a of the formwork shown in FIG. 1 is subjected to vibration and has a porosity of 7%, and is pushed by the local press plate 7 to have a porosity of 3%. 3 voids accounted for 7% of the concrete volume
%, so the volume has decreased by 4%. To put it simply, the thickness of concrete decreases by 4%,
The compression rate is 4% and the amount of indentation is 4% of the thickness.

In addition, as a hardened concrete product, the porosity is 3%.
is an ideal value, and according to the present invention, a value close to it can be obtained not only near the top surface of the formwork but also in the deep part.

The concrete pressing force applied by each press plate is determined by placing the actual concrete to be used in a simple mold, applying vibration and pressing down to achieve the above-mentioned porosity of 3.
It is advisable to decide experimentally so as to obtain %. usually,
0.5-1.0Kg/ ^cm2 or less is sufficient.

This invention is an instant demolding method in which concrete is locally supplied to the same formwork, after compaction, the entire concrete is replenished, and the entire surface is compacted. It is natural that various changes and applications will be made depending on the well-known technology of the person. For example, the local press plate that pushes the concrete that has entered the deep part of the formwork is usually different from the finishing press plate that presses the top surface of the formwork.
When the concrete is supplied in a sufficiently high heap to the deep part of the formwork like concrete C in FIG. 1, the finishing press plate 8 can also serve as the local press plate 7, and the local press plate can be omitted.

Further, the concrete supply mechanism is not limited to the sliding hopper type, but a well-known conveyor type can also be used, and in this case, selective supply to deep parts becomes easy.
Of course, a mold removal device such as a well-known mold reversal method or a lateral extrusion method can be used.

This invention takes up as an important problem the fact that when instant demolding is performed in the conventional method using formworks with different depths depending on the location, the compressibility of the concrete product inevitably varies depending on the location. As a solution to this problem, concrete is poured into the deep part of the formwork first and compressed, and when the remaining depth is approximately equalized, the formwork is filled with concrete and the entire surface is pressurized to finish.
provided the equipment. We also presented a press device with a dodging mechanism that allows the use of a local press plate for deep concrete and a finishing press plate for full-surface pressure on the same formwork.

This invention has made it possible for the first time to mass-produce concrete products with uneven surfaces with uniform porosity and strength even by instant demolding. Conventionally, shape,
Concrete products that previously had to rely on pour molding for strength reasons can now be manufactured using a highly efficient instant demolding method, which has great technical and economical effects.

[Brief explanation of drawings]

Figure 1 is an explanatory diagram of one embodiment of this invention, and Figures 2 to 4
5 is a perspective view of the concrete product, 6 and 7 are sectional views of other embodiments, 8 and 9 are sectional views of still further embodiments, and 5 is a perspective view of the concrete product. FIG. 10 is a cross-sectional explanatory diagram of another embodiment. 1... Formwork, 2... Vibration device, 4... Lifting frame for immediate demolding, 5... Fixed concrete hopper, 6...
...Sliding hopper, 7...Local press plate, 8...Finish press plate.

Claims (1)

[Claims] 1. First, hardened concrete is supplied to the deep part of the formwork, and the concrete is applied to the formwork by a local press plate while vibrating the formwork. The remaining depth of the formwork is approximately equalized by pushing the concrete with a pressure within a range that does not impair concrete fluidity due to vibration, and then pulling back the local press plate once or multiple times when the pushing stops. After that, hardened concrete is additionally supplied to fill the entire formwork, and the concrete product is finished by rolling it down with a finishing press plate that covers almost the entire surface of the formwork opening. 2. A formwork with different depths depending on the location, a vibration device for this formwork, an immediate demolding device, and a required amount of hardened concrete locally supplied to the deep part of the formwork, which can then be used to fill the entire formwork. A concrete feeding device that can be used, a local pre-press plate that pushes only the concrete supplied into the deep part, a finishing press plate that covers almost the entire surface of the formwork opening, and a dodging mechanism that allows both press plates to operate without any trouble. An instant demolding and molding device for concrete products, characterized by being equipped with a press device.