JPH0547372B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention uses cemented carbide concrete with an extremely low water/cement ratio, which is poured into a formwork and compacted by vibration, and the formwork is moved up and down at the unhardened concrete stage. The present invention relates to a method for molding concrete products that involves inversion and demolding, and a formwork used in the method.

[Conventional technology]

In order to form concrete products using cemented carbide concrete, a formwork is used in which a step is provided inside the frame and a bottom plate is supported on this formwork, and the concrete material placed in the formwork is subjected to vibration compaction. Afterwards, the formwork is moved to a curing area and manually rotated 90 degrees to stand up.One end of the formwork is supported on a flat surface such as a floor or pallet, and the exposed concrete side is placed at the bottom. Either invert the formwork by pushing it down so that the frame body and bottom plate are removed, or use a reversing device such as the one shown in Publication No. 13219/1983, and stack the pallets on the frame body. Invert it, move it to a curing area, and remove it from the mold.
After being reversed by a reversing device, it was removed from the mold on this device and transported to a curing place. Furthermore, as in the formwork device disclosed in Japanese Patent Application Laid-open No. 55-15804, a mold box whose lower end is sealed with a bottom plate is installed in the formwork equipped with a rotating shaft and a vibrator, and inside this mold box,
An elevating plate that is raised and lowered by a cylinder is installed, and hard mixed concrete is put into this form box. After compaction, the formwork with this form box attached is rotated around the rotation axis to lift the formwork. A known method is to use a cylinder to lower the elevating plate after being turned upside down and forcibly extrude the concrete product from the mold box to remove it from the mold.

[Problem to be solved by the invention]

However, when inverting the formwork manually, when one side of the formwork is supported on a flat surface, the concrete that has not yet solidified tends to shift within the formwork, and the impact caused by the inversion occurs. There were cases where the product lost its shape and the flat surface vibrated violently, causing the products already placed on it to collapse. Furthermore, when using the reversing device disclosed in Japanese Utility Model Publication No. 57-13219, a large installation space is required within the factory. In addition, pallets corresponding to the number and size of formwork are required, and the pallets must be placed together with the formwork in an inverting device, and after curing, the pallets from which concrete products have been removed must be transported to the inverting device. It didn't happen. In addition, the reversal demolding device disclosed in Japanese Patent Application Laid-Open No. 55-15804 is
The mold box is installed in a formwork equipped with a rotating shaft and a vibrator,
Concrete material is poured into this mold box and molded, and after the molding is completed, the mold box is turned upside down while still attached to the formwork, and the mold is removed, so the demolded concrete product is moved to a curing area. Until then, the next mold box cannot be set in the formwork. Moreover, since this mold box is sealed by the lower surface (bottom plate) to which the cylinder is fixed, compacted concrete cannot be removed from the mold even if the mold box is turned upside down. Therefore, the elevating plate is lowered using a cylinder to forcibly remove the mold. When the product is extruded from the mold box, if there is nothing to hold the bottom surface of the product, there is a risk that the part that has come out of the mold box will tear off due to its weight and collapse. A support device is required to place the pallet against the open end of the mold box and lower the pallet in accordance with the lowering of the elevating plate by the cylinder. Therefore, the method of the present invention has the disadvantage that the equipment cost increases significantly. Furthermore, even if the concrete product could be demolded onto a pallet without collapsing by providing the above-mentioned support mechanism, since the product is exposed except for the bottom surface, it may deform during transportation to the curing area. Otherwise, cracks may occur.

[Means to solve the problem]

In the molding method according to the present invention, the step formed on the inner periphery of the bottom of the frame body in the formwork and the bottom plate stacked on the top surface thereof are integrally tightened to close the lower opening of the frame body. Concrete material with a water-to-cement ratio of 39% or less is poured into the upper opening of the frame while applying vibrations, and the concrete material is fluidized by the vibration to form the interface with the inner surface of the formwork and the frame. After sealing the gap between the step and the bottom plate airtightly and compacting it until it self-retains the shape according to the formwork, the concrete surface exposed at the top opening of the frame is not covered. The formwork is suspended upside down and lowered onto a flat surface in the appropriate place to release the tension between the bottom plate and the formwork.The frame is then pulled up and separated from the uncured concrete product on the flat surface, and the bottom plate is removed. is characterized by detachment from the upper surface of the uncured concrete product. Further, the formwork according to the present invention has a stepped portion supporting the bottom plate formed on the inner periphery of the bottom of the frame body, and the bottom part of the frame body has a step portion that extends slidably through the side plate of the frame body in the axial direction. It is characterized by being equipped with a tightening device consisting of a horizontal shaft provided with a wedge piece, a spring that biases the horizontal shaft inward, and a catch for the wedge piece provided on the lower surface of the bottom plate.

[Effect]

In the forming method according to the present invention, when cemented carbide concrete is poured into the formwork and hardened by vibration compaction with the frame body and bottom plate integrally connected by a tightening device, the air permeability of the concrete is Furthermore, due to the tightness between the frame body and the bottom plate, the bottom plate adheres to the stepped part, and this contact area is sealed and integrated with the cement paste in the concrete material, so there is no leakage between the formwork and the concrete. Infiltration of outside air is completely prevented. Therefore, even if the formwork is turned over so that the open end faces downward, the compacted concrete material will not fall. To be more specific, when applying vibration to cemented carbide concrete whose water/cement ratio is less than 39% and whose slump value cannot be measured and is placed in a formwork, vibration and gravity must be applied. Compaction progresses due to the synergistic effect. In addition, the vibrations cause the aggregates to approach each other, and the cement paste covering the aggregates becomes fluid, gradually making the entire concrete fluid. In such a state, the concrete constituent materials sink due to gravity, while the air contained in the concrete is forced upwards and fills the gaps that exist in the upper part of the concrete and in the parts that are not yet fluid. and is released to the outside. After the air has been released and the concrete constituent materials have settled down, the fluidized concrete is further compressed using a pressure molding machine, and at the same time the molding finish near the formwork opening (concrete input port) is finished. administered. Compacted concrete becomes able to self-retain in a shape that conforms to the formwork. In other words, sufficiently compacted concrete does not allow any air to pass through, not only within the concrete but also at the interface between the concrete and the formwork.
Even when the formwork is turned upside down, the concrete remains within the formwork and does not partially fall off or become deformed. After compaction is completed in this way, the formwork is transferred to an appropriate flat surface, such as the floor of a curing area or onto a belt conveyor, suspended upside down, and lowered onto the flat surface to be demolded. Lower the formwork onto a flat surface, release the tightening device,
When you try to pull up the frame, outside air suddenly enters between the bottom plate and the stepped part of the frame, and the only force that resists the frame being removed is the frictional force between the concrete sides and the inner surface of the frame. This makes it impossible to counter the weight of the concrete and the bottom plate, so the frame can be easily pulled up and removed. In addition, the stepped part and bottom plate provided on the inner periphery of the bottom of the frame are as follows:
The horizontal shaft is advanced inward by the spring force, and the wedge piece provided at the inner end is press-fitted into the catch on the bottom surface of the bottom plate to tighten the horizontal shaft.The horizontal shaft is retreated outward against the spring force, and the wedge piece is The tension is released by leaving the catch.

【Example】

Next, an embodiment of the present invention will be described based on FIGS. 1 to 4. A is a metal formwork consisting of a frame 1 and a bottom plate 2, and a frame A is provided at the bottom of the frame 1. A bottom plate 2 is supported on a stepped portion 3 and a reinforcing frame 4. B is a tightening device installed at the bottom of formwork A,
A handle 7 is provided at the outer end of a horizontal shaft 6 that passes through a bearing cylinder 5 provided at the bottom of the frame 1 and a reinforcing frame 4,
A wedge piece 8 is provided at the inner end, and the horizontal shaft 6 is equipped with a spring 9 for urging it inwardly into the frame 1. On the other hand, a catch 10 is provided on the lower surface of the bottom plate 2. Groove 11 into which wedge piece 8 fits
is formed. The reference numeral 12 is a pin protruding from the outer end of the horizontal shaft 6, and 13 is a support groove for the pin 12 formed at the outer end of the bearing cylinder 5. 14 is concrete, 1
5 is a reinforcing bar. Reference numeral 16 is a support pin for the reinforcing bar 16, and its tip is connected to the frame body 1 by the advancement of the wedge plate 17.
It protrudes inward and is configured to retreat by spring force or the pressure of the concrete 14 when the wedge piece 17 retreats. Since one embodiment of the present invention has the above-mentioned configuration, the horizontal shaft 6 is advanced inside the frame body 1 by the elasticity of the spring 9, and the tip of the wedge piece 8 is moved as shown in FIGS. 1 to 4. After tightening the step part 3 of the frame body 1 and the bottom plate 2 by fitting it into the groove 11 of the catch 10, place the formwork A on the vibration table of the concrete molding machine with the tightening device B facing downward. Concrete material with a water/cement ratio of 39% or less is poured into the vibrating formwork A and compacted. When the wedge piece 8 receives vibration, its forward force is always promoted by the elasticity of the spring 9, so that the frame body 1 and the bottom plate 2 are tightened more reliably. In addition, in order to securely maintain the tension and facilitate removal without any trouble, it is necessary to use the wedge piece 8 and the catch 1.
It is naturally necessary to maintain the taper angle between the groove 11 and the groove 11 within a required range. Next, move this formwork A manually or by a conveyor to a curing area, turn it upside down while suspended, lower it onto a flat floor, and then use the handle of the horizontal shaft 6 as shown by the chain line in Fig. 4. 7 against the spring 9 to remove the wedge piece 8 from the groove 11 and lock the pin 12 to the outer end of the bearing cylinder 5. Then, the frame 1 is pulled up and the bottom plate 2 is placed in the concrete 14. Once released from the surface, the concrete product can be demolded without damage.

[Example 2] Figures 5 to 7 show the bottom plate 2 in the above example.
and the reinforcing plate 4 by a plurality of flexible connecting members 18.
This is the case when connected by. This connecting member 18 is designed so that when the frame 1 in an inverted state is pulled up as shown in FIG. The bottom plate 2 is formed so as to be easily bent and supported on the stepped portion 3 when the bottom plate 2 is turned over. Therefore, as the frame body 1 is pulled up, the bottom plate 2 is also pulled up. In addition, the bottom plate 2 remains on the product until the frame 1 is completely separated from the concrete product to protect the product, so when the frame 1 is pulled up, the frame 1 hits the top corner of the product and Cannot be damaged. The connecting member 18 is a bendable arm, but a chain, metal wire, string, etc. may be used instead. Reference numeral 19 is a handle for transporting formwork A.
Reference numeral 20 denotes a support shaft when the formwork A is turned upside down. Therefore, after vibration compaction of concrete is completed,
If the formwork A is transferred to a curing place by a conveyance machine using the above-mentioned transport handle 19, and while suspended in the air, the support shaft 20 is held in the bearing and the formwork A is gently rotated 180 degrees, the formwork A is turned upside down. . The other configurations are the same as those in Example 1, so
Explanation of the symbols of each part will be omitted.

[Embodiment 3] The embodiment shown in Figs. 8 to 11 is a formwork for molding two concrete products at the same time. A pair of partition frames 1a and 1b are formed, and a bottom plate 2 is fitted into each partition frame 1a and 1b, and the outer peripheral portion thereof is supported on a step 3 provided around the partition frames 1a and 1b. The reinforcing frame 4 provided in the compartment frames 1a, 1b and each bottom plate 2 are connected by a plurality of flexible connecting members 18, and each compartment frame 1a, 1
b and the two bottom plates are connected by a tightening device B. This tightening device B is provided with wedge pieces 8 at the inner ends of both the left and right horizontal shafts 6 that pass through the partition frames 1a and 1b and the reinforcing frame 4, as in the first and second embodiments. The bottom plate 2 is press-fitted to the step part 3 by being press-fitted with a spring 9 into the groove 11 of the catch 10 provided in the bottom plate 2. The outer ends of both horizontal shafts 6 are connected by a connecting plate 22, Press a wedge or the like into the space S between the frame body 1 and the connecting plate 2.
2 is pulled outward manually or mechanically to retract both horizontal shafts 6, and by maintaining this retracted state, the wedge piece 8 is separated from the groove 11, and the bottom plate 2 and the stepped portion are The structure is such that the crimping with 3 is released. Incidentally, the support pins 16 of the owl for holding the reinforcing bars 15 in the compartment frames 1a and 1b are installed on the outer walls of both the front and rear sides of the frame body 1, as in the first and second embodiments, and their tips are It penetrates the frame 1, protrudes into the partition frames 1a, 1b when moving forward, and its end surface coincides with the inner wall surface within the partition frames 1a, 1b when retreating. Further, each support pin 16 moves forward by the lateral movement of a wedge plate 17 provided on the outside of the frame 1, and retreats by the spring force or the pressure of the concrete 14 as the wedge plate 17 moves backward. In this embodiment, the wedge plates 17 are provided with movable rods 23 on both front and rear outer sides of the frame 1 so as to be movable left and right, and a plurality of wedge plates 17 are formed to move simultaneously by the left and right movement of the movable rods 23. are doing. Further, reference numeral 24 denotes a support stand 2 equipped with a vibrator 25.
These are a pair of left and right hook-shaped connecting parts that are used when fixing the formwork A on the top of the frame A. As shown in FIG. 11, the cylinder rod 27 is placed on a support stand 26, the flanged head 28 of the cylinder rod 27 exposed on the upper surface of the support stand 26 is inserted between the connecting parts 24, and the cylinder rod 27 is lowered to form the formwork A. In other words, the vibrator 25 is attached to the formwork A. Although the pair of left and right connecting portions 24 are fixed to the reinforcing frame 4, they may also be attached to the bottom plate 2. The tightening device B in this embodiment moves the left and right horizontal shafts 6 forward and backward at the same time, but similarly to the first and second embodiments, a method is adopted in which both horizontal shafts 6 are moved forward and backward by special rotation. Sometimes. Further, when the frame body 1 of the first and second embodiments is large, a plurality of tightening devices B may be provided as in the third embodiment. Furthermore, it goes without saying that various locking devices can be used in place of the tightening devices in the first and second embodiments.

【Effect of the invention】

According to the forming method of the present invention, concrete material with a water/cement ratio of 39% or less is poured into a formwork in which the bottom plate is tightened against the frame body, and after compaction is performed by vibration, the formwork is The concrete can be removed from the mold by simply turning it upside down while suspended in the air, lowering it onto a flat surface in the appropriate place, and then releasing the tightening of the bottom plate, making demolding work very easy. In addition, once compacted formwork is completed, it can be moved to an appropriate position and then removed from the mold, so work efficiency can be improved by setting a new formwork in the molding machine during the movement. can. Furthermore, since the concrete product is being moved, its outer periphery is covered with formwork, so there is no risk of deformation or cracking. In addition, even if the formwork is hung upside down without covering the concrete surface exposed at the top opening of the formwork, the concrete will not fall out of the formwork and will not lose its shape. Not only is there no need for holding means or the large-scale reversing device used in the past, but the holding work is also no longer necessary, which reduces equipment costs and production costs, greatly improving work efficiency. can. According to the formwork of the present invention, the wedge piece provided at the inner end of the tightening device is fitted into the catch on the lower surface of the bottom plate by moving the horizontal shaft of the tightening device forward by the spring force or by moving it backward against the spring force. It is extremely easy to operate because it is detached and tightens and releases the step and bottom. Moreover, in the tightened state, since the wedge piece is pressed into the catch by the spring, the movement of the formwork makes the fit between the wedge piece and the catch even more reliable, and there is no possibility that the tightening will loosen. By employing the molding method of the present invention and the formwork used therein, it is possible to automate molding equipment for various concrete products using hard mixed concrete.

[Brief explanation of the drawing]

FIG. 1 is a bottom view showing a first embodiment of the formwork according to the present invention, FIG. 2 is a partially vertical side view of the same embodiment,
FIG. 3 is a bottom view showing the main parts of the same embodiment, FIG. 4 is a vertical sectional view taken along the line X-X shown in FIG. 3, FIG. 5 is a bottom view showing the second embodiment, and FIG. FIG. 7 is a partial vertical sectional view showing the demolding state of the above embodiment, FIG. 8 is a bottom view of the third embodiment, and FIG. 9 is a partial longitudinal sectional view of the above embodiment. Partial longitudinal sectional view, No. 10
FIG. 11 is a perspective view showing the main parts of the embodiment, and FIG. 11 is a partially cutaway side view showing the embodiment installed in a molding machine. A...Formwork, B...Tightening device, 1...Frame body, 2
...Bottom plate, 3...Step part, 4...Reinforcement plate, 5...Bearing cylinder, 6...Horizontal shaft, 7...Handle, 8...
Wedge piece, 9...Spring, 10...Catch, 1
1...Groove, 12...Pin, 13...Support groove, 14
... Concrete, 18 ... Connecting member.

Claims (1)

[Scope of Claims] 1. After closing the lower opening of the frame by integrally tightening the step formed on the inner periphery of the bottom of the frame in the formwork and the bottom plate stacked on the top surface thereof, the formwork Concrete material with a water-to-cement ratio of 39% or less is poured into the upper opening of the frame while applying vibrations, and the concrete material is fluidized by the vibration to form the interface with the inner surface of the formwork and the frame. After the gap between the stepped part and the bottom plate is airtightly sealed and compacted until it self-retains the shape according to the formwork, the concrete surface exposed at the top opening of the frame is not covered. The formwork is suspended upside down and lowered onto a flat surface in the appropriate place to release the tension between the bottom plate and the formwork.The frame is then pulled up and separated from the uncured concrete product on the flat surface, and the bottom plate is removed. A method for forming a concrete product, characterized in that the material is separated from the upper surface of an uncured concrete product. 2. A step part is formed on the inner periphery of the bottom of the frame body to support the bottom plate, and the bottom part of the frame body is provided with a wedge piece at the inner end of the frame body, which passes through the side plate of the frame body so as to be slidable in the axial direction. A formwork used in a method for forming concrete products, characterized in that it is equipped with a tightening device consisting of a horizontal shaft, a spring that biases the horizontal shaft inward, and a wedge catch provided on the lower surface of the bottom plate.