JP4346583B2 - Mold for molding concrete products with hollow parts - Google Patents

Description

  The present invention makes it possible to easily separate and exclude (hereinafter referred to as “demolding”) a mold used after completion of a molding process of a concrete product having a hollow portion, particularly an inner mold, and manufacture the next concrete product. And a molding die that can be easily restored to its initial shape and dimensions.

  When trying to demold a finished mold of a concrete product with a hollow part, an outer mold with space for taking out the mold or mold parts can be removed relatively easily, but is there no space to take it out? In the case of an inner mold (also referred to as a core) that has a very limited space, it is very difficult to remove the mold.

  Conventionally, there are a mold, a wooden mold, a plastic mold, an FRP mold and the like as a mold for molding a concrete product having a hollow portion. The main mold is made of steel, but the product hardens and shrinks after completion of molding, making it very difficult to remove the mold. Therefore, for example, a conventional mold is a mold composed of a large number of members called so-called split molds, and has a complicated structure composed of fastening parts such as a cam, a link mechanism and bolts and nuts that connect these numerous members. . In addition, a release agent is applied to make the removal easier.

In addition, as a conventionally known technique, as a mold that can be used to facilitate the process of removing the inner mold (core) from the product after the molding process of a concrete product having a hollow portion has been completed. For example, what was described in patent document 1 is known. That is, the core used in the manufacture of hollow concrete products is formed of an iron-based shape memory alloy whose shape memory is several percent smaller than the product dimensions, and the inside is expanded to the product dimensions by applying a water pressure of ² to 5 kg / mm ^2. The core is casted into concrete, and after solidifying the concrete, it is heated to 100 ° C or higher, preferably 200 ° C or higher, to recover its shape, and a few percent gap is formed between the concrete and the core to remove the mold. It is what you do.
JP-A-9-193127

  The prior art has an extremely complicated structure consisting of a large number of parts and various parts such as bolts, nuts, cams, links and the like for connecting the parts to form a mold, and various separations. Although the use of molds has been attempted, satisfactory results have not been obtained. That is, the difficulty of mold removal causes a reduction in work efficiency and product quality / performance, and a large number of components causes an increase in mold price.

  Moreover, in what was described in patent document 1 as a well-known technique, (1) The said inner frame requires the expansion process which applied the internal pressure before using it as a core, and this process is required every time. . This leads to a significant decrease in work efficiency, which is contrary to the purpose of improving productivity and reducing product cost. (2) It is unclear how much the core will settle when the internal pressure is removed after the core is expanded by applying internal pressure. This leads to a decrease in dimensional accuracy, which improves product quality and improves product quality. Contrary to the purpose of improving performance. (3) Although it is said that the entire core must be formed of an iron-based shape memory alloy, this means that various types of processing that are inappropriate for shape memory alloys such as curved surface processing, deep drawing processing, welding processing, etc. In addition to the necessity, it is difficult to obtain a material having a necessary dimensional specification, or even if it is available as a custom-made product, it becomes extremely expensive. In particular, when the size of the treat product is increased, the entire core must be formed of an iron-based shape memory alloy, which is expensive. (4) A high temperature of 100 ° C. or higher, preferably 200 ° C. or higher is required for the shape recovery of the core. In this case, only the inside of the product concrete is heated, so that the product concrete cracks due to non-uniform heating. Incidentally, paragraph [0003] of Patent Document 1 states that “the concrete and steel have substantially the same linear expansion coefficient ...”, so the thermal expansion coefficient of concrete is not so small that it can be ignored. In addition, the occurrence of cracks due to uneven heating is inevitable. (5) In order to obtain working efficiency at a practical level, high-frequency induction heating is necessary. This leads to an increase in the size of the mold structure, which is contrary to the purpose of reducing and simplifying the mold price.

  In view of the situation as described above, the present invention solves the problems of the prior art, and reduces the mold price by reducing the number of parts constituting the mold, and improves the efficiency of the demolding work. Accordingly, an object of the present invention is to provide a mold for molding a concrete product having a hollow portion that can realize a reduction in the price of the product.

  The present invention provides a very effective method for removing the inner mold even in such a limited space. The principle of the present invention is that the required dimensions for the molding dimensions (product dimensions) and the dimensions at the time of demolding. It is to cause a dimensional difference. That is, in the case of the inner mold, the mold dimension at the time of demolding may be changed so as to be smaller than the mold dimension at the time of molding.

  Such changes in mold dimensions required during demolding are expressed using the shape restoring force of Ti-Ni-based shape memory alloys, and after demolding, the molds are restored to their original shapes and dimensions. To return, the strain energy stored in the mold material itself, or the strain energy stored in the soft elastic body filled in the slit formed in the mold material itself and the mold, and arranged in the joint part of the mold divided into multiple parts A hollow part with a function capable of expressing a reversible shape and dimensional change only by giving a temperature change to a Ti-Ni shape memory alloy by using strain energy stored in a soft elastic body. It is an object and a feature of the present invention to provide a concrete molding die having

  Further, the present invention allows a reversible shape change between the shape at the time of demolding and the initial shape only by giving a temperature change to the Ti-Ni-based shape memory alloy. It is a mold for molding concrete products with extremely high performance and high performance hollow parts that do not require operation. The outline of the means is a configuration in which a slit (slit) is provided in a part of the mold body, and an elastic body much softer than the material of the mold body is loaded into the slit, or when nothing is loaded, the slit is a thin plate sleeve Or it is set as the structure covered with a tape. Alternatively, the mold is divided into a plurality of parts, and a soft elastic body is interposed in the joint part. As a means for reversibly deforming the mold between the shape at the time of demolding and the initial shape, the shape recovery force generated by the elastic modulus change accompanying the phase transformation due to the temperature change of the Ti-Ni type shape memory alloy, and the mold Alternatively, strain energy stored in a soft elastic body as a mold component is used.

  That is, the elastic modulus (Young's modulus or shear coefficient) of the Ti—Ni-based shape memory alloy varies significantly between the austenite state (hereinafter referred to as “high temperature state”) and the martensite state (hereinafter referred to as “low temperature state”). In general, the former is 3 to 10 times the latter, and this difference is focused on.

  For example, in a mold having a Ti—Ni type shape memory alloy member whose elastic modulus in a high temperature state is five times the elastic modulus in a low temperature state, that is, in a mold for molding, the shape memory of the Ti—Ni type is used. When the shape change of the alloy member is linked to the shape change of the molding die, the molding shape is changed to the required shape in the low temperature state, that is, the shape of the fluidized concrete casting state. After the casting of the fluidized concrete to the mold and the hardening process thereof is completed, when the Ti-Ni-based shape memory alloy member undergoes a temperature change to a high temperature state, it tries to recover to a pre-stored shape. Sometimes, the elastic modulus also changes five times as described above, and therefore the shape is restored with a force five times the force that worked at low temperatures, so that the soft elastic body as the inner frame material or mold component is deformed. The inner frame material or the soft quality elastic strain energy is stored in accordance with the deformation amount.

  However, since the allowable deformation amount is within the elastic limit and the inner frame material is usually made of steel, the elastic limit is much smaller than the elastic limit of the soft elastic body. By removing the mold in this state, one molding process is completed.

  Next, when the Ti—Ni-based shape memory alloy member is cooled to a low temperature state, the elastic modulus also decreases to the original value (1/5 times that at a high temperature), so that the mold material or the soft elastic body It is returned to the original shape (shape at low temperature) of the mold material or the soft elastic body by losing the elastic restoring force (force to return to the shape before being deformed). In order to generate the elastic restoring force, strain energy stored in the mold material or the soft elastic body is used.

  The transformation temperature from the martensite phase to the austenite phase is called a reverse transformation temperature, and the reverse transformation temperature can be adjusted by the heat treatment temperature and time.

Therefore, a mold for molding a concrete product having a hollow portion of the present invention is:
For molding concrete products with a hollow part in which fluidized concrete is poured into a mold with an outer frame and an inner frame, and after the fluidized concrete has hardened, the mold is removed to produce a concrete molding. In the mold,
It is provided with a peeling movement means that engages with the inner frame, peels the concrete molding and the inner frame, and moves the inner frame from the molding,
The inner frame can be reversibly switched between the initial shape at the time of fluidized concrete injection and the shape at the time of demolding of the shape change of the inner frame due to temperature application after hardening of the fluidized concrete, from the initial shape to the shape at the time of demolding. When the shape changes, the energy storage structure having a slit for storing strain energy in the inner frame,
And a sleeve member covering at least the slit portion provided in the inner frame,
The peeling movement means is
A Ti-Ni-based shape memory alloy member that changes the inner frame from the initial shape to the shape at the time of demolding by applying temperature from the outside;
A shape memory alloy member is held, and an inner frame fastening tool that engages with an engaging portion formed in a slit forming portion of the inner frame is provided, and the shape change of the shape memory alloy member from the initial shape to the shape at the time of demolding The inner frame is contracted via the inner frame fastener when the shape memory alloy member is restored to the initial shape, and the shape of the inner frame is removed from the initial shape via the inner frame fastener. First holding engagement means for restoring the shape of the shape memory alloy member from the shape at the time of demolding to the initial shape by the strain energy accumulated in the inner frame at the time of the shape change to
It is characterized in that a concrete molding can be manufactured.

The mold for molding a concrete product having a hollow portion of the present invention is
For molding concrete products with a hollow part in which fluidized concrete is poured into a mold with an outer frame and an inner frame, and after the fluidized concrete has hardened, the mold is removed to produce a concrete molding. In the mold,
It is provided with a peeling movement means that engages with the inner frame, peels the concrete molding and the inner frame, and moves the inner frame from the molding,
The inner frame can be reversibly switched between the initial shape at the time of fluidized concrete injection and the shape at the time of demolding of the shape change of the inner frame due to temperature application after hardening of the fluidized concrete. When changing the shape of the energy storage structure having a slit for storing strain energy in the inner frame and a soft elastic body loaded in the slit,
The peeling movement means is
A Ti-Ni-based shape memory alloy member that changes the inner frame from the initial shape to the shape at the time of demolding by applying temperature from the outside;
A shape memory alloy member is held, and an inner frame fastener that engages with an engaging portion formed in a slit forming portion of the inner frame is provided, and the shape change of the shape memory alloy member from the initial shape to the shape at the time of demolding At the time, the inner frame and the soft elastic body are reduced through the inner frame fastener, and when the shape memory alloy member is restored to the initial shape, the initial position of the inner frame is reduced through the inner frame fastener. The shape of the shape memory alloy member is changed from the shape at the time of demolding to the initial shape by the strain energy accumulated in the inner frame at the time of the shape change from the shape to the shape at the time of demolding and the strain energy accumulated in the soft elastic body. First holding engagement means for restoring ,
It is characterized in that a concrete molding can be manufactured.

The mold for molding a concrete product having a hollow portion of the present invention is
For molding concrete products with a hollow part in which fluidized concrete is poured into a mold with an outer frame and an inner frame, and after the fluidized concrete has hardened, the mold is removed to produce a concrete molding. In the mold,
It is provided with a peeling movement means that engages with the inner frame, peels the concrete molding and the inner frame, and moves the inner frame from the molding,
Each of the inner frames is provided with an inner frame facing member, and has two symmetrical inner frame constituent members that should constitute the inner frame. It is possible to reversibly change the shape of the frame from the shape at the time of demolding, and at the time of the shape change from the initial shape to the shape at the time of demolding, it is disposed at the connecting portion of the two inner frame constituent members. An energy storage structure having a soft elastic body for storing strain energy;
And a sleeve member that covers at least a gap generated between the two inner frame facing members facing each other due to the soft elastic body on the outer peripheral surface of the inner frame formed by the two inner frame constituting members,
The peeling movement means is
A Ti-Ni-based shape memory alloy member that changes the inner frame from the initial shape to the shape at the time of demolding by applying temperature from the outside;
An inner frame fastening tool that holds the shape memory alloy member and engages with an engaging portion provided on each of the inner frame facing members that are arranged to face each other, from the initial shape of the shape memory alloy member The shape of the soft elastic body is reduced via the inner frame fastener when the shape is changed to the shape at the time of demolding, and the shape memory alloy member is restored via the inner frame fastener when the shape is restored to the initial shape. The shape of the shape memory alloy member is restored from the shape at the time of demolding to the initial shape by the strain energy accumulated in the soft elastic body at the time of the shape change from the initial shape of the inner frame to the shape at the time of demolding. Two holding engagement means,
It is characterized in that a concrete molding can be manufactured.
The mold for molding a concrete product having a hollow portion of the present invention is
For molding concrete products with a hollow part in which fluidized concrete is poured into a mold with an outer frame and an inner frame, and after the fluidized concrete has hardened, the mold is removed to produce a concrete molding. In the mold,
It is provided with a peeling movement means that engages with the inner frame, peels the concrete molding and the inner frame, and moves the inner frame from the molding,
The inner frame can be reversibly switched between the initial shape at the time of fluidized concrete injection and the shape at the time of demolding of the shape change of the inner frame due to temperature application after hardening of the fluidized concrete, from the initial shape to the shape at the time of demolding. When the shape changes, the energy storage structure having a soft elastic body for storing strain energy, each disposed at each coupling portion of the inner frame of the inner frame constituting member forming the inner frame,
The peeling movement means is
A Ti-Ni-based shape memory alloy member that changes the inner frame from the initial shape to the shape at the time of demolding by applying temperature from the outside;
An inner frame expansion / contraction mechanism that holds the shape memory alloy member and engages with an engagement portion provided on the inner frame and expands / contracts the side surface of each inner frame component member that forms the inner frame in a direction perpendicular to the side surface. When the shape of the shape memory alloy member changes from the initial shape to the shape upon demolding, the soft elastic body is reduced via the inner frame expansion / contraction mechanism, and the shape memory alloy member is restored to the initial shape. The shape of the shape memory alloy member is shaped at the time of demolding by the strain energy accumulated in the soft elastic body during the shape change from the initial shape of the inner frame to the shape at the time of demolding through the inner frame expansion / contraction mechanism. And a third holding engagement means for restoring the initial shape from
It is characterized in that a concrete molding can be manufactured.

  The soft elastic body includes a general-purpose rubber, a homogeneous soft elastic body including silicone rubber, and a thin metal, a net-like metal, a general-purpose plastic, a reinforced plastic, a fiber, and a woven hard elastic body in a layered structure between the homogeneous soft elastic bodies. A layered soft elastic body or a foamed soft elastic body containing sponge rubber is used.

The mold for molding a concrete product having a hollow portion of the present invention is
For molding concrete products with a hollow part in which fluidized concrete is poured into a mold with an outer frame and an inner frame, and after the fluidized concrete has hardened, the mold is removed to produce a concrete molding. In the mold,
A peeling movement means for engaging the inner frame and the outer frame, peeling the concrete molding and each contact surface of the inner frame and the outer frame, and moving the molding from the inner frame and the outer frame;
The peeling movement means is
For driving the pusher that moves the movable ring plate via the pusher to move the movable ring plate that is movably disposed at the bottom of the space formed by the inner frame and the outer frame by applying temperature from the outside. Ti-Ni shape memory alloy that changes the space formed by the inner and outer frames and the movable ring plate from the initial shape to the shape at the time of demolding by inducing strain in the soft elastic body and accumulating strain energy A member,
At least two terminal alloy holders containing the shape memory alloy member in a form in which one of the two ends is in contact with each other;
It is arranged between the two terminal alloy holders and is penetrated in a skewered manner by the shape memory alloy member, and the extension of the shape memory alloy member extends between the two terminal alloy holders. A soft elastic body for compressing and deforming a pusher driving soft elastic body, and storing a strain energy corresponding to the compression deformation in the pusher driving soft elastic body;
The initial shape of the space formed by the inner and outer frames and the movable ring plate when injecting fluidized concrete, and the shape at the time of demolding that has changed shape due to temperature application after fluidized concrete hardening, while engaging with the inner and outer frames 2 is reversibly possible, strain energy is accumulated in the soft elastic body for driving the pusher due to the change in shape of the shape memory alloy member, and the pusher is driven based on the temperature change of the shape memory alloy member. With the energy storage structure that makes it possible to restore the space formed by the inner and outer frames and the movable ring plate to the initial shape of the original shape by the strain energy stored in the soft elastic body,
The initial shape of the space formed by the inner frame, the outer frame, and the movable ring plate before and after the temperature is applied to the shape memory alloy member and by the forced compression of the shape memory alloy member from the outside, and the shape at the time of demolding It is characterized in that the shape of the molding form can be changed by reversible mold deformation to produce a concrete molding.

The mold for molding a concrete product having a hollow portion of the present invention is
For molding concrete products with a hollow part in which fluidized concrete is poured into a mold with an outer frame and an inner frame, and after the fluidized concrete has hardened, the mold is removed to produce a concrete molding. In the mold,
It is provided with a peeling movement means that engages with the inner frame, peels the concrete molding and the inner frame, and moves the inner frame from the molding,
The peeling movement means is
Ti-Ni-based shape memory alloy member that changes the inner frame from the initial shape to the shape at the time of demolding by applying strain to the inner frame and accumulating strain energy by applying temperature from the outside, and one of both ends Are arranged between the at least two shape memory alloy holders and the two shape memory alloy holders, and penetrated in a skewered manner by the shape memory alloy members. A shape memory alloy unit comprising a soft elastic body that is compressed together with a shape memory alloy member and stores compression deformation energy when the space between the two shape memory alloy holders is compressed;
The shape memory alloy unit can be reversibly engaged with the inner frame, and can be reversibly two forms: an initial shape at the time of pouring the fluidized concrete and a shape at the time of demolding by changing the shape of the inner frame by applying temperature after the fluidized concrete is cured. The strain energy is accumulated in the inner frame itself due to the shape change of the inner frame, and the energy that makes it possible to restore the inner frame to the initial shape by the strain energy accumulated in the inner frame itself based on the temperature change of the shape memory alloy member With a storage structure,
The shape of the mold for molding is obtained by reversible mold deformation between the initial shape of the inner frame and the shape at the time of demolding before and after applying temperature to the shape memory alloy member and by forced compression of the shape memory alloy unit from the outside. This is characterized in that it is possible to produce a concrete molding.

  By simply giving a temperature change to the Ti-Ni-based shape memory alloy, a reversible shape change is possible between the shape at the time of demolding and the initial shape, so no human manipulation other than giving a temperature change is required. A mold for molding a concrete product having a very high performance and high performance hollow part is realized, and the manufacturing work of the concrete product becomes easy.

  Since it is not necessary to use an expensive shape memory alloy for the entire mold, and the structure thereof is also simple, it becomes a mold for molding a concrete product having an inexpensive hollow portion.

  It is only necessary to give a temperature change to the shape memory alloy as the mold constituent material, and it is not always necessary to change the temperature of the entire mold including the mold itself. The mold for molding can be easily designed, and the dimensions of the concrete product are highly accurate.

  Since the mold itself is not made of a shape memory alloy, there is an advantage that a large apparatus is not required for applying a temperature change, particularly heating, to the shape memory alloy.

  Hereinafter, embodiments of the present invention will be described with reference to FIGS.

  FIG. 1 is a plan view of a cylindrical mold according to an embodiment of a mold for molding a concrete product having a hollow portion according to the present invention, and FIG. 2 is a cross-sectional view taken along line AA of FIG.

  1 and 2 for producing hollow cylindrical concrete, 1 is an inner frame (core), 2 is an outer frame, 3 is a peeling moving means, 4 is a shape memory alloy spring, and 5 is an inner frame fastener. , 6 is a soft elastic body, 7 is a spring shaft, 8 is an outer frame sealing fitting, 9 is an outer frame sealing bolt, and 10 is a molding.

  In manufacturing the hollow cylindrical concrete molding 10, for example, a steel member is used for the inner frame 1 and the outer frame 2 that determine the outer diameter, the inner diameter, and the length of the cylinder constituting the outer frame 2. An outer frame slit portion 11 is provided in the axial direction.

  As shown in FIG. 1, the outer frame 2 is provided with an outer frame sealing metal fitting 8 in the form of the outer frame slit portion 11 inside, and is used for sealing the outer frame attached to the outer frame sealing metal fitting 8. By screwing the bolt 9, it is possible to open and close the outer frame slit portion 11, in particular, to prevent leakage of the fluidized concrete and to open the hardened article 10 for easy removal. It is configured as follows.

  Two inner frame slit forming portions 13 are formed on the inner diameter surface of the inner frame 1 in the axial direction, and the inner frame 1 in the portion of the two inner frame slit forming portions 13 is shown in FIG. The inner frame slit 12 having the same cross section as the soft elastic body 6 is provided. Inside the inner frame 1, a plurality of peeling movement means 3 are arranged at appropriate positions along the inner frame slit 12 according to the length of the inner frame 1.

  A soft elastic body 6 is fitted into the inner frame slit 12 formed in the inner frame 1 so that the fluidized concrete does not leak into the inner side of the inner frame 1. An arrow shape is used for the cross section of the soft elastic body 6, and this arrow shape is a shape for preventing the soft elastic body 6 from coming off the inner frame slit 12.

  The soft elastic body 6 is made of a general-purpose rubber, foam material (sponge rubber, etc.), a homogeneous soft elastic body such as silicone rubber, and a thin metal sheet, a net-like metal or a general-purpose plastic between the homogeneous soft elastic body, In some cases, a layered soft elastic body in which hard elastic bodies such as reinforced plastics, fibers, and fabrics are combined in layers is used. In either case, the cross section perpendicular to the longitudinal direction is solid or hollow. There may be.

  The soft elastic body 6 used here effectively accumulates the strain energy generated during the deformation of the soft elastic body 6 and prevents the injected concrete from entering the inner frame 1. In addition, when the mold is removed, the pressing action of the concrete occurs due to the strain in the direction perpendicular to the load direction and does not interfere with the demolding, that is, the longitudinal strain in the load direction applied from the inner frame slit forming portion 13. A material having a large so-called Poisson's ratio with a small transverse strain in the vertical direction is selected.

  The peeling moving means 3 acts on the inner frame 1 to peel the inner frame 1 from the contact surface of the hardened concrete molding 10, that is, to separate the inner frame 1 and move it away from the surface of the molding 10. The mold 10 of the molding 10 is easily removed, and the inner frame slit 12 is pressed by engaging with the inner frame slit forming portion 13 provided in the inner frame 1 as its operation. The soft elastic body 6 fitted in is compressed to generate a gap between the inner frame 1 and the molding 10.

  That is, the peeling moving means 3 includes an inner frame fastening tool 5 that engages with the inner frame slit forming part 13 via two tip parts 5b, and a shape of a Ti—Ni-based shape memory alloy used as a torsion coil spring. A memory alloy spring 4 and a spring shaft 7 attached to an inner frame fastener 5 for fixing the shape memory alloy spring 4 are constituted.

  When the contact portion 5a of the inner frame fastener 5 engaged with both arms 4a of the shape memory alloy spring 4 acts in the opening direction due to the operation of the shape memory alloy spring 4, the inner frame fastener The two end portions 5b of 5 compress the soft elastic body 6 through the pressing of the inner frame slit forming portion 13, and the inner frame 1 is peeled off from the contact surface of the concrete molding object 10, that is, the above separation and separation. The movement is caused to act so as to generate a gap between the inner frame 1 and the molding 10.

  Now, the angle formed by the two arms 4a of the shape memory alloy spring 4 is α (see FIG. 1), and the angle formed by the two arms 4a when the shape memory process is performed is β (in FIG. (Not shown), β is always set to be larger than α, and the shape memory alloy spring 4 is within a range in which the shape memory alloy spring 4 can be incorporated into the inner frame fastener 5 and the spring shaft 7 in a low temperature state. Thus, the difference is set as large as possible (β >> α).

  When the shape memory alloy spring 4 whose angle between the two arms 4a is α in the low temperature state is changed to a high temperature state, the elastic modulus of the shape memory alloy spring 4 is remarkably increased and the shape memory alloy spring 4 is shaped. The inner frame fastener engaged with the arm 4a of the shape memory alloy spring 4 because the shape is to be restored to the angle (β) subjected to the memory processing with an increased force equal to the rate of increase of the elastic modulus. 5, the inner frame fastener 5 is moved in the direction of closing the front end portion 5 b, and is engaged with the front end portion 5 b, that is, the two inner frame slit forming portions 13 engaged with each other. Acts in the direction of closing. As a result, the inner elastic slit 12 operates in the closing direction to compress and deform the soft elastic body 6. At this time, the diameter of the inner frame 1 is reduced by 1 / π (≈3.14) of the closing amount of the inner frame slit 12, and this amount becomes a gap generated between the workpiece 10 and the inner frame 1. .

  Due to the shape change of the inner frame 1 and the soft elastic body 6, strain energy is accumulated in the inner frame 1 itself and in the soft elastic body 6. When the Poisson's ratio of the soft elastic body 6 is small, the amount of protrusion (strain) in the pressing direction of the molding 10 compared to the closing amount of the inner frame slit 12, that is, the strain amount of the soft elastic body 6 in the load direction. Since the amount is small, it is possible to prevent an action that hinders demolding. And it contributes greatly to the gap | interval production | generation of the to-be-molded product 10 and the inner frame 1 while accumulating big strain energy in the soft elastic body 6, preventing the leakage of fluid concrete. In this way, demolding is completed with the shape memory alloy spring 4 kept in a high temperature state.

  Next, when the shape memory alloy spring 4 is returned to the low temperature state again, the elastic modulus of the shape memory alloy spring 4 is also reduced to the low temperature state value, so that it has been stored in the inner frame 1 or the soft elastic body 6. Strain energy is used to return the shape of the inner frame 1 or the soft elastic body 6 to the original state, and the angle formed by the two arms 4a of the shape memory alloy spring 4 is also returned to the angle α in the low temperature state. It is. In this way, a part of the inner frame 1, that is, the shape memory alloy spring 4 or all of the inner frame 1, that is, the entire inside of the inner frame 1 to which the shape memory alloy spring 4 is attached is simply subjected to temperature change at the time of demolding. A reversible shape change is possible between the initial shape and the shape, so that it is possible to realize a mold for molding concrete products with a very high performance and high performance hollow part that does not require any human manipulation other than giving a temperature change. .

  Moreover, in the present invention, the entire inner frame 1 does not have to be composed of an expensive shape memory alloy at all, and the shape memory alloy spring 4 is used as a demolding drive source for the inner frame 1, that is, a Ti-Ni type shape. Based on the characteristics of the memory alloy, a configuration is adopted in which the inner frame 1 that can be inexpensively removed is demolded via a boosting mechanism based on the lever principle.

  Incidentally, in the case of the iron-based shape memory alloy described in Patent Document 1 known as the prior art, there is no change in the elastic modulus between the low temperature state and the high temperature state, so there is no external force operation as in the present invention. The present invention greatly differs from the prior art in the technical idea for solving the problem in that the reversible shape change cannot be expressed.

  In this way, the inner frame 1 of the molding die is subjected to a temperature change accompanying the phase transformation of the shape memory alloy used in the shape memory alloy spring 4, whereby the diameter of the inner frame 1 is reversible. The amount of change is 1 / π of the amount of displacement of the tip 5b of the inner frame fastener 5, that is, the amount of displacement of the inner frame slit forming portion 13. For example, when it is desired to change the diameter of the inner frame 1 by 1 mm, the distal end portion 5b of the inner frame fastener 5, that is, the inner frame slit forming portion 13 may be changed by 3.14 mm. For example, in the case of the shape memory alloy spring 4 used in one embodiment of the present invention, the elastic modulus at a high temperature is about 5 times that at a low temperature. The amount is about 5 times that at low temperatures.

  On the other hand, although the gap necessary for demolding depends on the size of the molding 10, it is experientially set to several mm per unit length (1 m). If the displacement amount of the inner frame slit forming portion 13 is (2 to 3 mm) × 3.14≈6 to 9 mm, the core, that is, the inner frame 1 can be easily pulled out.

  As described above, according to the present invention, [1] a large number of bolts, nuts, cams, links and the like are not required, so the structure is simple and advantageous in terms of dimensional accuracy and price. [2] At least the shape memory alloy spring 4 Since it is possible to develop a reversible shape change simply by giving a temperature change to the part of [3], there is no need for mold expansion treatment by applying internal pressure. [3] The mold body, that is, the inner frame 1 and the outer frame 2 are very general purpose. The amount of the shape memory alloy used for the shape memory alloy spring 4 is very small, so it is advantageous in price. [4] The temperature required for demolding is about 80 ° C. [5] As a heat source necessary for demolding, there is no occurrence of cracks due to non-uniform heating, and simple means such as hot water, steam, red heat lamp, energizing heater, etc. are sufficient, and can be found in Patent Document 1 known as the prior art. Like high An expensive device such as frequency induction heating is unnecessary.

  FIG. 3 is a plan view of another embodiment of a cylindrical mold for molding a concrete product having a hollow portion according to the present invention.

  As in the case of FIG. 1, in FIG. 3 for producing hollow cylindrical concrete, the same components as those in FIG.

  3, the inner frame 1, the outer frame 2, the peeling moving means 3, the shape memory alloy spring 4, the arm 4a, the inner frame fastener 5, the contact portion 5a, the tip portion 5b, the spring shaft 7, and the outer frame sealing metal fitting. 8, the outer frame sealing bolt 9, the molded article 10, the outer frame slit portion 11, and the inner frame slit forming portion 13 are the same as those in FIG.

  Reference numeral 14 denotes a sleeve, 15 denotes an inner frame slit, 16 denotes a slit portion, and 17 denotes a sealing material.

  The outer peripheral surface of the inner frame 1 has a structure covered with a sleeve 14, and a so-called core as a general term apparently has a double structure composed of the original inner frame 1 and the sleeve 14. You may think. Unlike the case of FIG. 1, nothing is inserted into the inner frame slit 15 provided in the inner frame 1.

  The sleeve 14 is formed of, for example, a thin steel plate as much as possible as long as it can withstand the hydrostatic pressure of fluidized concrete. The sleeve 14 facilitates demolding. When demolding, the sleeve 14 may be removed separately from the inner frame 1 or may be removed together with the inner frame 1. As shown in FIG. 3, the sleeve 14 is provided with a slit portion 16 in the axial direction of the inner frame 1.

  The gap of the slit portion 16 is filled with a putty or other sealing material 17. By filling the sealing material 17 in the slit portion 16, the fluid concrete enters the slight gap between the inner frame 1 and the sleeve 14 from the slit portion 16 and is hardened, and the inner diameter dimension of the article 10 is further changed. The inner frame slit 15 is prevented from leaking into the inner frame 1 from the inner frame slit 15.

  Instead of the sleeve 14, an adhesive tape such as stainless steel, aluminum or cloth may be used. In this case, these alternative adhesive tapes are directly adhered to the outer peripheral surface of the inner frame 1. In this case, it is not necessary to cover the entire outer surface of the inner frame 1 with these tapes, and it may be a very limited portion covering the inner frame slit 15.

  As in the case of FIG. 1, the angle formed by the two arms 4a of the shape memory alloy spring 4 is now α (see FIG. 3), and the angle formed by the two arms 4a when the shape memory process is performed is β. (Β is not shown in FIG. 3), β is always set to be larger than α, and the shape memory alloy spring 4 is in a low temperature state and the inner frame fastener 5 and the spring shaft 7 are set. The difference is set to be as large as possible (β >> α) within a range that can be incorporated into.

  When the shape memory alloy spring 4 whose angle between the two arms 4a is α in the low temperature state is changed to a high temperature state, the elastic modulus of the shape memory alloy spring 4 is remarkably increased and the shape memory alloy spring 4 is shaped. The inner frame fastener engaged with the arm 4a of the shape memory alloy spring 4 because the shape is to be restored to the angle (β) subjected to the memory processing with an increased force equal to the rate of increase of the elastic modulus. 5, the front end portion 5b of the inner frame fastening tool 5 is closed, and the two inner frame slits 15 engaged with the front end portion 5b, that is, engaged with each other, are closed. At this time, the diameter of the inner frame 1 is reduced by 1 / π (≈3.14) of the closing amount of the inner frame slit 15 as described with reference to FIG. There is a gap between them.

  That is, when the sleeve 14 is deformed integrally with the inner frame 1, all the gaps described above are generated between the molded object 10 and the sleeve 14. When the sleeve 14 is not deformed integrally with the inner frame 1, The sum of the gap formed between the sleeve 10 and the sleeve 14 and the gap formed between the inner frame 1 and the sleeve 14 is equal to the entire gap. Further, in the case where the sleeve 14 is in close contact with the molding 10 even though the inner frame 1 is deformed, all the above-described gaps are generated between the sleeve 14 and the inner frame 1. Then, depending on which of the above three states, the sleeve 14 is determined as being integrated with the inner frame 1 or separately from the inner frame 1. When the above-mentioned adhesive tape is used in place of the sleeve 14, the adhesive tape is removed as an integral part of the inner frame 1.

  As described above, demolding is completed in a state where the shape memory alloy spring 4 is kept at a high temperature. Needless to say, strain energy is accumulated in the inner frame 1 itself due to the shape change of the inner frame 1.

  Next, when the shape memory alloy spring 4 is returned to the low temperature state again, the elastic modulus of the shape memory alloy spring 4 also decreases to the low temperature value, so that the strain energy stored in the inner frame 1 is used. As a result, the shape of the inner frame 1 is returned to the original state, and the angle formed by the two arms 4a of the shape memory alloy spring 4 is also returned to the angle α in the low temperature state. In this way, a part of the inner frame 1, that is, the shape memory alloy spring 4 or all of the inner frame 1, that is, the entire inside of the inner frame 1 to which the shape memory alloy spring 4 is attached is simply subjected to temperature change at the time of demolding. A reversible shape change is possible between the initial shape and the shape, so that it is possible to realize a mold for molding concrete products with a very high performance and high performance hollow part that does not require any human manipulation other than giving a temperature change. .

  FIG. 4 shows a plan view of another embodiment of a cylinder mold for a concrete product having a hollow portion according to the present invention.

  As in the case of FIG. 1, in FIG. 4 for producing hollow cylindrical concrete, the same components as those in FIG.

  In FIG. 4, an inner frame (core) 1, an outer frame 2, a soft elastic body 6, an outer frame sealing metal fitting 8, an outer frame sealing bolt 9, a molding 10, an outer frame slit portion 11, and an inner frame slit 12. The inner frame slit forming portion 13 is the same as that shown in FIG.

  Reference numeral 21 denotes a peeling movement means, 22 denotes a shape memory alloy spring, and 23 denotes an inner frame clamp, corresponding to the peeling movement means 3, the shape memory alloy spring 4 and the inner frame clamp 5 in FIG. It is.

  The peeling moving means 21 acts on the inner frame 1 to peel the inner frame 1 from the contact surface of the hardened concrete molded object 10, that is, to separate the inner frame 1 and to move away from the surface of the molded object 10. The mold 10 can be easily removed from the mold, and as an operation thereof, the inner frame slit 12 is pressed by engaging with the inner frame slit forming portion 13 provided in the inner frame 1. The inserted soft elastic body 6 is compressed to generate a gap between the inner frame 1 and the molding 10.

  That is, the peeling moving means 21 is composed of an inner frame fastening tool 23 that engages with the inner frame slit forming part 13 through two tip parts 23b, and two Ti—Ni-based shape memory alloys used as coil springs. The shape memory alloy spring 22, the two opening / closing members 25 swingably swinging around the shaft 24, and the inner frame fastener 23 are swingably swingable about the inner frame fastener 23. A fastening bolt 26 and a nut fastening member 26 for fixing the memory alloy spring 22 are formed.

  When the two opening / closing members 25 act in the closing direction (the state shown in FIG. 4) due to the movement of the shape memory alloy spring 22, both end portions 23 b of the inner frame fastener 23 are pressed by the inner frame slit forming portion 13. The soft elastic body 6 is compressed via the inner frame 1, and the inner frame 1 acts to cause the above-described peeling and movement, and to generate a gap between the inner frame 1 and the molding 10.

In other words, the shape memory alloy spring 22 of the coil spring type is formed as a “high temperature elongation type spring”, that is, when the shape memory alloy spring 22 is at a low temperature, the length L of the coil portion is set as a mold component. If the shape memory processing length of the coil portion is set at L ₀ when assembled, it means that the shape memory processing is performed so that the relationship between L ₀ and L always satisfies L ₀ > L. When the shape memory alloy spring 22 is in a high temperature state, the two opening / closing members 25 of the inner frame fastener 23 are moved with the same force as the elastic modulus ratio between the low temperature state and the high temperature state as in the case of FIG. Since the pressing is performed, the peeling moving means 21 is operated in a direction to close the inner frame slit 12 according to the force.

  The separation mechanism of the inner frame 1 from the molding 10 and the mechanism of the reversible shape change of the inner frame 1 are exactly the same as in FIG. Also, the material and characteristics of the soft elastic body 6 are the same as those in FIG.

  4, the structure shown in FIG. 3, that is, the outer peripheral surface of the inner frame 1 may be covered with the sleeve 14 or other above-described material so that the soft elastic body 6 is not used. .

  FIG. 5 shows a partial cross-sectional view of a bottomed cylindrical mold according to another embodiment of a mold for molding a concrete product having a hollow portion according to the present invention.

  Also in FIG. 5 which manufactures hollow cylindrical concrete with a bottom, the same code | symbol is attached | subjected to the same thing as FIG.

  In FIG. 5, an inner frame (core) 1, an outer frame 2, a peeling movement means 3, a shape memory alloy spring 4, an inner frame fastening tool 5, a spring shaft 7, an outer frame sealing fitting 8, and an outer frame sealing bolt 9. The molding object 10 is the same as that shown in FIG.

  5 is formed so that the upper end of the inner frame 1 is shorter than the upper end of the outer frame 2 and a stepped protrusion on the upper end surface of the inner frame 1 in order to form a concrete bottom on the one shown in FIG. 27 is provided, and a disc-shaped bottom plate 28 is placed on the stepped protrusion 27 via a ring-shaped bottom plate elastic seal 29. That is, the bottom plate elastic seal 29 is disposed so as to interpose the stepped protrusion 27 formed on the inner frame 1 and the bottom plate 28, and can sufficiently absorb the dimensional change of the inner frame 1 during molding and demolding. Therefore, it is made of the same material as the soft elastic body 6 described in FIG.

  In the mold for molding a bottomed cylindrical concrete product having a hollow portion according to the present invention, a stepped protrusion 27 is provided on the upper end surface of the inner frame 1 described in FIG. The structure in which the plate-like bottom plate 28 is placed via the bottom plate elastic seal 29 can also be applied to the already described FIGS. 3 and 4.

  And what stores strain energy in the inner frame 1 through the inner frame slits 12 and 15 provided in the inner frame 1 using a shape memory alloy spring is the inner frame tightening shown in FIGS. The mechanism is not limited to the mechanism of the tools 5 and 23, and any other mechanism can be used as long as it has the same function as the inner frame fastening tools 5 and 23.

  FIG. 6 is a plan view of another embodiment of a mold for molding a concrete product having a hollow portion according to the present invention, and FIG. 7 is a sectional view taken along line BB of FIG.

  6 and 7 for producing hollow rectangular concrete, 31 is an inner frame, 32 is an outer frame, 33 is a peeling movement means, 34 is a shape memory alloy spring, 35 is an inner frame fastener, and 36 is soft elastic. , 37 is a spring shaft, 38 is an outer frame sealing metal fitting, 39 is an outer frame sealing bolt, 40 is an object to be molded, and 41 is a sleeve.

  In manufacturing the hollow square cylindrical concrete molding 40, the inner frame 31 and the outer frame 32 that determine the vertical, horizontal, and length are made of, for example, steel members, and a rectangular tube is formed. ing.

  As shown in FIG. 6, the outer frame 32 is provided with two outer frame sealing metal fittings 38, and by screwing an outer frame sealing bolt 39 attached to the outer frame sealing metal fitting 38, The outer frame 32 is opened and closed in a completed shape, and is particularly configured to enable the role of leak-proof sealing of fluid concrete and opening for easy demolding of the cured workpiece 40. Yes.

  More specifically, the outer frame 32 is formed by a combination of two outer frame components, that is, a left outer frame 32a and a right outer frame 32b having the same shape. The inner frame 31 is a left inner frame 31a having two inner frame components, that is, a left inner frame 31a and a right inner frame 31b having the same shape obliquely crossing the inside of the inner frame 31. The structure which forms one type | mold is used with the form which couple | bonded the soft elastic body 36 on both sides of the inner frame opposing member 31c and the right inner frame opposing member 31d which comprises the right inner frame 31b. A gap G (the existence of the gap G is shown in FIG. 6) between one end surface (the inclined surface side in FIG. 6) of the soft elastic body 36 and the inner surface of the sleeve 41 covering the outer peripheral surface of the inner frame 31. Are drawn exaggerated for clarity).

  The sleeve 41 covering the outer peripheral surface of the inner frame 31 has a structure in which cuts 42 are provided in the axial direction of the inner frame 31 at two corners forming the diagonal of the inner frame 31 as shown in FIG. The gap 42 is filled with a putty or other sealing material 43.

  Then, as in the case described in FIG. 3 of the second embodiment, instead of the sleeve 41, for example, an adhesive tape such as stainless steel, aluminum, or cloth may be used. In this case, these adhesive tapes are directly adhered to the inner frame 31. Also in this case, it is sufficient that the injected fluid concrete has a function of preventing the injected fluid concrete from leaking to the inside of the inner frame 31, so it is not necessary to cover the entire outer surface of the inner frame 31 with these tapes. It may be a very limited part of a range covering the soft elastic body 36 disposed between the frame facing member 31c and the right inner frame facing member 31d. Further, when the soft elastic body 36 is partially covered without using the sleeve 41, the soft elastic body 36 is attached to the outer peripheral surface of the inner frame 31 in the same manner as when the outer peripheral surface of the inner frame 31 is covered with the sleeve 41. It is arranged in a state where a slight gap G is maintained between the tape and the tape.

  The reason for securing the gap G is that when the soft elastic body 36 is subjected to compressive deformation at the time of demolding, the soft elastic body 36 swells in the direction of the tape perpendicular to the compressed direction due to the influence of the Poisson's ratio. This is for preventing the molding 40 from being pressed and hindering the demolding. In short, it is only necessary that the gap G be kept at a size that abuts against the tape but is not pressed when the soft elastic body 36 swells and expands and does not hinder demolding. This dimension is determined by calculation or based on experimental results. In the case where the sleeve 41 is used, it goes without saying that the gap G has a size that abuts against the sleeve 41 but is not pressed when the soft elastic body 36 swells and expands.

  The peeling movement means 33 acts on the inner frame 31 to peel the inner frame 31 from the contact surface of the hardened concrete molding 40, that is, to separate the inner frame 31 and move it away from the surface of the molding 40. The mold 40 can be easily removed from the mold, and two tip portions 35b forming a pair of inner frame fasteners 35 as an operation thereof are a left inner frame 31a, a right inner frame 31b, and two soft members. The inner frame 31 formed of the elastic body 36 is provided on the left inner frame facing member 31c and the right inner frame facing member 31d, which are opposed to each other while the left inner frame 31a and the right inner frame 31b are inclined to face each other. By pressing through the engagement with the wedge groove portion 47, the soft elastic bodies 36 are compressed to generate a gap between the inner frame 31 and the molding 40.

  The left inner frame facing member 31c of the left inner frame 31a is provided with a window 44 as shown in FIG. The same applies to the right inner frame facing member 31d of the right inner frame 31b, and a plurality of peeling moving means 33 are provided along the window 44 at appropriate intervals. 45 is a base board, and 46 is a base seal member.

  Further, the peeling moving means 33 basically has the same structure as the peeling moving means 3 described with reference to FIG. 1 and has an inner frame fastening tool 35 that engages with the wedge groove part 47 through two tip parts 35b. , A shape memory alloy spring 34 of a Ti—Ni shape memory alloy used as a torsion coil spring, a spring shaft 37 attached to an inner frame fastener 35 for fixing the shape memory alloy spring 34, and the like. .

  When the contact portion 35a of the inner frame fastening tool 35 engaged with both arms 34a of the shape memory alloy spring 34 acts in the opening direction due to the operation of the shape memory alloy spring 34, the inner frame fastening. Both end portions 35b of the tool 35 compress the soft elastic body 36 by pressing the wedge groove portion 47, and the inner frame 31 peels from the contact surface of the concrete molding 40, that is, the above-described separation and movement. And act to generate a gap between the inner frame 31 and the molding 40.

  When a gap is generated between the inner frame 31 and the molding 40, each of the soft elastic bodies 36, and in this case, the value of the left inner frame 31a and the right is slightly smaller than that of the soft elastic body 36. Needless to say, strain energy is also accumulated in each of the inner frames 31b. However, since the amount is very small, it may be considered that it can be ignored.

  After the fluidized concrete is cast between the inner frame 31 and the outer frame 32 set to the required dimensions in consideration of the finished dimensions of the product at low temperatures, and after completing a predetermined curing process, the shape memory alloy spring When the temperature changes beyond the reverse transformation point temperature, the inner frame fastener 35 is moved by a force having the same magnification as the elastic modulus ratio between the low temperature state and the high temperature state, as in the case of the cylindrical type in FIG. The distal end portion 35b is closed and a force is applied to each wedge groove 47 portion of the left inner frame 31a and the right inner frame 31b to compress the soft elastic body 36 so that the left inner frame 31a and the right inner frame 31b are separated from each other. Shrink.

That is, as shown in FIG. 6, when the left inner frame 31a and the right inner frame 31b of the inner frame 31 are coupled to the horizontal surface of the mold through the soft elastic body 36 at an angle γ, the soft elastic body 36 is used. Causes a displacement of δ, a displacement of δ _x = δ sin γ in the horizontal direction and δ _y = δ cos γ in the vertical direction occurs. For example, in order to generate a displacement of 1 mm in both the horizontal direction and the vertical direction, assuming that γ = 45 °, the displacement δ of the soft elastic body 36 is set to δ = 1 / sin 45 ° = 1 / cos 45 °. = 1.414 mm may be displaced.

  As described above, when the mold is removed in a high temperature state and the shape memory alloy spring 34 is returned to a low temperature state again after the mold release, the elastic modulus of the shape memory alloy spring 34 is also reduced to a low temperature state value. The elastic elastic body 36 cannot withstand the elastic restoring force, and the strain energy stored in the soft elastic body 36 is used to restore the shape of the soft elastic body 36 to the original state. It is returned to the state.

  As described above, the cylindrical mold shown in FIGS. 1 to 5 can reversibly change the mold into a shape at the time of molding and a shape at the time of demolding only by a temperature change without artificial manipulation. Same as the case. Since the same applies to the material of the soft elastic body 36, the description thereof is omitted.

  In the above description, the case of producing the hollow rectangular concrete concrete molding 40 has been described. However, the cross section can be replaced with a circular shape and used as a cylindrical concrete molding die.

  FIG. 8 shows a sectional view of a bottomed square tube mold according to another embodiment of the mold for molding a concrete product having a hollow portion according to the present invention.

  The formwork for producing the bottomed hollow square tubular concrete in FIG. 8 is provided with a formwork for forming the bottom on the formwork for producing the hollow square tubular concrete described in FIGS. 6 and 7. , Inner frame 31, outer frame 32, peeling moving means 33, shape memory alloy spring 34, inner frame fastener 35, spring shaft 37, molding 40, sleeve 41, etc. 8 may be the same as those described in FIG. 6 and FIG.

  8 is formed so that the upper end of the inner frame 31 is shorter than the upper end of the outer frame 32 in order to form the bottom of the concrete shown in FIGS. A projection 48 is provided, and a rectangular bottom plate 49 is placed on the stepped projection 48 via a bottom plate elastic seal 50. That is, the bottom plate elastic seal 50 is disposed so as to interpose the stepped protrusion 48 formed on the inner frame 31 and the bottom plate 49, and the dimensional change of the inner frame 31 during molding and demolding is sufficiently absorbed. Therefore, it is made of the same material as the soft elastic body 6 described in FIG.

  Although the description is omitted in FIG. 7, as in the case of FIG. 7, the base seal material 46 is formed so as to be in close contact with the outer periphery of the four sides of the sleeve 41 and the inner periphery of the four sides of the outer frame 32. Arranged so as not to leak outside when cast. On the base board 45, the inner frame 31 and the outer frame 32 are arranged so that the entire mold is integrated with the base seal material 46 interposed therebetween.

  FIG. 9 is a plan view of another embodiment of a mold for molding a concrete product having a hollow portion according to the present invention, and FIG. 10 is a cross-sectional view taken along the line CC in FIG.

  9 and 10 for producing hollow rectangular concrete, 61 is an inner frame (core), 62 is an outer frame, 63 is a peeling movement means, 64 is a shape memory alloy spring, 65 is a spring holder, 66 is The shape memory alloy spring system, 67 is a spring shaft, 68 is an outer frame sealing metal fitting, 69 is an outer frame sealing bolt, and 70 is an object to be molded.

  In producing the hollow square cylindrical concrete molding 70, the inner frame 61 and the outer frame 62 that determine the vertical, horizontal, and height are made of, for example, steel members, and are configured as two pairs of inner frames. The body 61a, 61b forms a skeleton of the inner frame 61 constituting the square tube, and the two identical outer frame members 62a, 62b are combined to form the square tube outer frame 62.

  As shown in FIG. 9, the outer frame 62 is provided with outer frame sealing fittings 68 at the two corners thereof, and the outer frame sealing bolts 69 attached to the outer frame sealing fittings 68 are screwed around. As a result, the outer frame 62 is formed, and is particularly configured to enable the role of sealing to prevent leakage of fluid concrete and opening for easy removal of the molding 70 of the hardened concrete.

  That is, the inner frame 61 has a soft elastic body 71 interposed at each of four corners, that is, corners, and has a square shape as shown in FIG. 9 by adhesion or external force preload (tensile force of the shape memory alloy spring system 66 in a low temperature state). It is formed in a rectangular tube shape. Further, load transmission screws 72 for transmitting a load from the shape memory alloy spring system 66 are respectively implanted on each of the four sides of the inner frame 61, that is, each of the two inner frame components 61a and 61b. The load transmission screw 72 has a structure in which one end of a load transmission rod 73 is coupled to freely rotate. The other end of the load transmission rod 73 has a structure that is rotatably coupled to the load transmission screw 74 implanted in the spring holder 65 of the shape memory alloy spring system 66.

  A shape memory alloy spring 64 similar to the Ti-Ni type shape memory alloy spring 4 described in FIG. 1 is incorporated in a spring shaft 67 inside the spring holder 65 constituting the shape memory alloy spring system 66. The spring shaft 67 is attached to a spring holder 65.

  In FIG. 9, one peeling moving means 63 is disposed in each inner frame constituting body 61a, 61b corresponding to the inner frame 61. Accordingly, it goes without saying that the peeling moving means 63 are arranged at appropriate intervals according to the size and length of the inner frame 61.

  As the soft elastic body 71 used at the four corners of the inner frame 61, the same material as that of the soft elastic body 6 described in FIG. 1 is used, and the one having a small Poisson's ratio is selected.

  In FIGS. 9 and 10 for manufacturing the hollow rectangular concrete structured as described above, the fluidized concrete is cast between the inner frame 61 and the outer frame 62 in a low temperature state, and the fluidized concrete is completely cured. After that, when the shape memory alloy spring 64 is changed in temperature not lower than its reverse transformation point temperature by means not shown, the shape memory alloy spring 64 is transformed from the martensite phase to the austenite phase and its elastic modulus is also increased. As mentioned above, it becomes about 5 times larger. At this time, since the planting piece 75 (see FIG. 9) of the load transmitting screw 74 planted on the spring holder 65 is configured to close to each other, two pairs of inner frames 61 are formed. Each inner frame component 61a, 61b is peeled off from the contact surface of the hardened concrete molding 70 with a force about five times as large as that at low temperature, that is, separated and pulled in the moving direction away from the concrete surface. To do.

  At this time, the inner frame components 61 a and 61 b of the inner frame 61 are translated toward the center thereof, so that the soft elastic body 71 is compressed and strain energy is accumulated in the soft elastic body 71.

Further, in the enlarged view of the soft elastic body 71 arranged at the four corners of the inner frame 61 in FIG. 11, the inner frame constituting bodies 61a and 61b on the two sides of the inner frame 61 orthogonal to each other are moved away from the hardened concrete ( As a result of being pulled in the x and y directions), the soft elastic body 71 has a rectangular cross section of width b × length h as shown in FIG. When the direction of each side of the body (X, Y direction) forms an angle θ with the x, y direction, the deformation of the soft elastic body 71 in the lateral direction (X direction) is δ _x = 2s · cos θ. Therefore, the strain in the X direction of the soft elastic body 71 is ε _x = δ _x / b = 2 s · cos θ / b. If the Poisson's ratio is ν, the strain in the Y direction is ε _Y = −νε _x = −2 νs · cos θ. / B. At this time, the deformation in the Y direction is δ _Y = hε _Y = −2 hνs · cos θ / b. In this case, since ε _x is a compressive strain and ε _Y has the opposite sign, ε _Y is an elongation strain and δ _Y is an elongation deformation. Therefore, when the inner frame components 61a and 61b on the two sides of the inner frame 61 move by s in the direction away from the hardened concrete, the deformation that the soft elastic body 71 acts to press the hardened concrete is δ _c = δ _Y / 2 = −hνs · cos θ / b.

For example, if θ = 45 ° and h / b = 1 and the Poisson's ratio of the soft elastic body 71 is i = 0.25 to 0.3, then δ _c = −0.18 s to −0.21 s. .

On the other hand, the amount by which the soft elastic body 71 moves away from the hardened concrete is m = s · sin θ = 0.71 s, and the gap generated between the soft elastic body 71 and the hardened concrete is k = When m + δ _c = 0.53 s to 0.5 s and the soft elastic body 71 is subjected to compressive deformation, the soft elastic body 71 and the molding 70 are in spite of swelling in a direction perpendicular to the compressed direction. A gap of 0.53 to 0.5 times the inner frame movement amount s is secured between the gaps, and swelling (elongation deformation) in a direction perpendicular to the gap caused by compression deformation of the soft elastic body 71 is demolded. There will be no hindrance.

  After the mold release is completed in this way, when the shape memory alloy spring 64 is cooled to the original state (low temperature state), the elastic modulus of the shape memory alloy spring 64 also returns to the original value, and the tensile force is also low. Since the tensile force in the state is restored, the mold shape of the inner frame 61 returns to the original state (low temperature state) by being pushed back by the elastic restoring force due to the strain energy stored in the soft elastic body 71.

  In this way, the shape at the time of demolding can be obtained simply by giving a temperature change to a part of the inner frame 61, that is, the shape memory alloy spring 64 or all, that is, the entire inner frame 61 to which the shape memory alloy spring 64 is attached. It is possible to realize a mold for molding a concrete product having an extremely high-performance and high-performance hollow portion that can reversibly change its shape between the initial shape and, therefore, does not require an artificial operation other than giving a temperature change.

  FIG. 12 shows a cross-sectional view of a bottomed square tube mold according to another embodiment of the mold for forming a concrete product having a hollow portion according to the present invention.

  The formwork for producing the bottomed hollow square tubular concrete in FIG. 12 is provided with a formwork for forming the bottom on the formwork for producing the hollow square tubular concrete described in FIGS. 9 and 10. The inner frame (core) 61, the outer frame 62, the peeling and moving means 63, the shape memory alloy spring system 66, the molded object 70, and the like may be considered the same as those described with reference to FIGS.

  12, the upper end of the inner frame 61 is formed to be shorter than the upper end of the outer frame 62 so as to form a concrete bottom as shown in FIGS. 9 and 10, and a step is formed on the upper end surface of the inner frame 61. A projection 78 is provided, and a rectangular bottom plate 79 is placed on the stepped projection 78 via a rectangular frame-shaped bottom plate elastic seal 80. That is, the bottom plate elastic seal 80 is disposed so as to interpose the stepped protrusion 78 formed on the inner frame 61 and the bottom plate 79, and the dimensional change of the inner frame 61 during molding and demolding is sufficiently absorbed. Therefore, it is made of the same material as the soft elastic body 6 described in FIG.

  Further, the base seal material 76 is formed so as to be in close contact with the outer periphery of the four sides of the inner frame 61 and the inner periphery of the four sides of the outer frame 62, and is arranged so as not to leak to the outside when casting the fluidized concrete. An inner frame 61 and an outer frame 62 are arranged on the base board 77 so that the entire mold is integrated with a base seal material 76 interposed therebetween.

  FIG. 13 is a plan view of another embodiment of a mold for forming a concrete product having a hollow portion according to the present invention, and FIG. 14 is a sectional view taken along the line DD of FIG.

  In FIGS. 13 and 14 for producing hollow rectangular concrete, 61 is an inner frame (core), 62 is an outer frame, 64 is a shape memory alloy spring, 65 is a spring holder, 66 is a shape memory alloy spring system, 67 represents a spring shaft, 68 represents an outer frame sealing metal fitting, 69 represents an outer frame sealing bolt, and 70 represents an object to be molded, which are the same as those in FIGS. 9 and 10.

  The separation moving means 83 includes four load support frames 84 provided inside the inner frame 61 and four attached to the load support frame 84 corresponding to the inner frame constituting bodies 61a and 61b constituting the inner frame 61, respectively. The shape memory alloy spring system 66 is composed of four load transmission rods 85, one fixed to the load support frame 84 and the other fixed to the opposing inner frame components 61a and 61b. The load support frame 84 has a hole for each load transmission rod 85 through which the load transmission rod 85 passes loosely.

  The inner frame 61 includes soft elastic bodies 71 at four corners, that is, corners, and has a substantially square cross section as shown in FIG. 13 by adhesion or external force preload (pressing force of the shape memory alloy spring system 66 in a low temperature state). It is formed in a square tube shape.

  A shape memory alloy spring 64 similar to the Ti-Ni type shape memory alloy spring 4 described in FIG. 1 is incorporated in a spring shaft 67 inside the spring holder 65 constituting the shape memory alloy spring system 66. The spring shaft 67 is attached to a spring holder 65.

  As the soft elastic body 71 used at the four corners of the inner frame 61, the same material as that of the soft elastic body 6 described in FIG. 1 is used, and the one having a small Poisson's ratio is selected.

  In a low temperature state, the fluidized concrete is cast between the inner frame 61 and the outer frame 62. After the concrete is hardened, the temperature is applied by means not shown in the figure, and the shape memory alloy spring 64 is heated above its reverse transformation point temperature. Then, the martensite phase is transformed into the austenite phase and the elastic modulus is increased by about 5 times as described above. At this time, since the load transmission rod penetrating side portion 86 (see FIG. 14) forming a pair of the spring holder 65 operates in the opening direction, the inner frame constituting bodies 61a and 61b of the inner frame 61 have a force at a low temperature. It peels, that is, separates from the contact surface of the hardened concrete molding 70 with a large force of about 5 times, and is pulled in the moving direction away from the concrete surface to release the mold.

  At this time, the inner frame components 61 a and 61 b of the inner frame 61 are translated toward the center thereof, so that the soft elastic body 71 is compressed and strain energy is accumulated in the soft elastic body 71.

  After the mold release is completed in this way, when the shape memory alloy spring 64 is cooled to the original state (low temperature state), the elastic modulus of the shape memory alloy spring 64 also returns to the original value, and the tensile force is also low. Since the tensile force in the state is restored, the mold shape of the inner frame 61 returns to the original state (low temperature state) by being pushed back by the elastic restoring force due to the strain energy stored in the soft elastic body 71.

  FIG. 15 shows a sectional view of a bottomed square tube mold according to another embodiment of the mold for molding a concrete product having a hollow portion according to the present invention.

  The formwork for producing the hollow square tubular concrete with a bottom in FIG. 15 is provided with a formwork for forming the bottom on the formwork for producing the hollow square tubular concrete described in FIGS. 13 and 14. The inner frame (core) 61, the outer frame 62, the shape memory alloy spring system 66, the molding 70, the soft elastic body 71, the peeling movement means 83, the load transmission rod 85, etc. are the same as those described with reference to FIGS. You can think of it as the same.

  15, the upper end of the inner frame 61 is formed shorter than the outer frame 62 to form a concrete bottom in the one shown in FIGS. 13 and 14, and a stepped protrusion is formed on the upper end surface of the inner frame 61. 78, and a rectangular bottom plate 79 is placed on the stepped protrusion 78 via a rectangular frame-shaped bottom plate elastic seal 80. That is, the bottom plate elastic seal 80 is disposed so as to interpose the stepped protrusion 78 formed on the inner frame 61 and the bottom plate 79, and the dimensional change of the inner frame 61 during molding and demolding is sufficiently absorbed. Therefore, it is made of the same material as the soft elastic body 6 described in FIG.

  The base seal material 81 is formed so as to be in close contact with the outer periphery of the four sides of the inner frame 61 and the inner periphery of the four sides of the outer frame 62, and is arranged so as not to leak to the outside when casting the fluidized concrete. An inner frame 61 and an outer frame 62 are arranged on the base board 82 so that the entire mold is integrated with the base seal material 81 interposed therebetween.

  FIG. 16 shows a plan view of another embodiment of a mold for forming a concrete product having a hollow portion according to the present invention.

  In the case of FIG. 16 which manufactures a hollow rectangular tubular concrete, the peeling movement means 83 is replaced with the shape memory alloy spring system 66 in FIG. 13 described above, and a Ti—Ni type shape memory alloy spring 87 is used as a coil spring. The shape memory alloy spring 87 is attached to the opposite side of the inner frame 61, that is, the inner frame constituting bodies 61a and 61b, with fixing bolts 88 that loosely penetrate the holes formed in the load supporting frame 84. It is a thing.

  Except that the shape memory alloy coil spring 87 is formed so as to extend at a high temperature, the demolding mechanism is the same as that described with reference to FIG.

  When the bottomed square cylindrical concrete is produced also in the mold for molding the concrete product having the hollow portion, the mold for forming the bottom of the concrete has a mold structure similar to that in the case of FIG. Since the structure is the same as in FIG. 15, the description thereof is omitted.

  And what accumulate | stores strain energy in the soft elastic body which comprises the inner frame 61 using a shape memory alloy spring is not restricted to the thing of the structure illustrated in FIG. 9 thru | or FIG. 16, It has the same function. Any other structure can be used.

  FIG. 17 is a partial cross-sectional view of another embodiment of a mold for molding a concrete product having a hollow portion according to the present invention, and FIG. 18 is a partial cross-sectional view when fluidized concrete is injected in FIG.

  Here, a mold for producing hollow cylindrical concrete will be described.

  17 and 18 for producing hollow cylindrical concrete is provided with a mechanism in which a shearing force is applied between the mold and the hardened concrete and is demolded by the force.

  In FIG. 17, 101 is a cylindrical inner frame (core), 102 is a cylindrical outer frame arranged outside the inner frame 101, and 103 is a peeling movement means arranged inside the cylinder of the inner frame 101. The peeling moving means 103 is configured as follows.

  As shown in FIG. 17, the round bar linear Ti—Ni-based shape memory alloy 111 is arranged concentrically along the outer periphery of the holding bolt 121 in a plurality of layers (three layers in FIG. 17). . The shape memory alloy 111 arranged concentrically in each layer has a ring-shaped intermediate alloy holder 112 around the axis of the holding bolt 121 and a ring-shaped soft elastic body around the axis of the holding bolt 121. A plurality of stages (six stages in FIG. 17) are stacked through 113, and the intermediate alloy holder 112 and the soft elastic bodies 113 in all stages are concentrically arranged. The structure is pierced with the memory alloy 111, that is, penetrated.

  Both ends of the upper end and lower end of the shape memory alloy 111 are held in contact with the upper and lower end alloy holders 114a and 114b, respectively. The uppermost terminal alloy holder 114a is in contact with the presser plate 115, and the lowermost terminal alloy holder 114b is in contact with the upper base plate 117 via the bottom plate portion 101a of the inner frame 101, respectively. All the shape memory alloys 111 arranged in a shape are held in a form sandwiched between the presser plate 115 and the upper base plate 117.

  The presser plate 115 and the bottom plate portion 101a of the inner frame 101 are disposed so as to be sandwiched between the presser nut 116 and the upper base plate 117. Between the upper base plate 117 and the lower base plate 120, a ring shape is provided. The central soft elastic body 118 and the peripheral soft elastic body 119 are provided. The lower base plate 120 is structured to be supported by the bolt head 121 a of the presser bolt 121.

  The peeling moving means 103 further includes an extrusion bolt 125 and a movable ring plate 126 described below.

The length of the shape memory alloy 111 shown in FIG. 17 is a length (L ₀ ) previously stored in the shape memory, and in this state, the shape memory alloy 111 is compressed by turning the presser nut 116. This compression amount δ (see FIG. 18) is maintained by the tensile force acting on the presser bolt 121 after all, but the presser bolt 121 is considerably thick and the elongation due to the tensile force is negligibly small. In consideration of the fact that the uppermost and lowermost alloy holders 114a and 114b and the intermediate alloy holder 112 are made of steel, the amount δ is a compression of a plurality of soft elastic bodies 113 arranged between them. It will be absorbed by deformation. The state at that time is shown in FIG.

  The soft elastic body 113 used here is made of the same material as the soft elastic body 6 shown in FIG. 1, that is, when the soft elastic body 113 returns to its original shape (the deformed shape returns to its original shape). A material that effectively stores the generated strain energy and has a Poisson's ratio as small as possible is selected.

Here, when the shape memory length of the shape memory alloy 111 is L ₀ as described above and the length of the shape memory alloy 111 after compression is L _l , L ₁ = L ₀ −δ.

  More specifically, FIG. 18 is a view showing a state where fluid concrete is poured, that is, an initial state. On the other hand, in the demolding state, the shape memory alloy 111 tries to return to the shape memorized in shape, that is, the length shown in FIG. 118 and the peripheral soft elastic body 119 are compressed, and as a result, the extruded bolt 125 pushes up the object to be molded, that is, the hardened fluidized concrete 105 through the movable ring plate 126. Incidentally, FIG. 17 is only one process that passes when the mold is manufactured and assembled.

  In the initial formwork state shown in FIG. 18, fluid concrete is poured into a space formed by the inner frame 101 and the outer frame 102.

  Referring to FIGS. 17 and 18, after the fluidized concrete is hardened after a predetermined time has elapsed, from the water injection port 122 provided in the presser plate 115, the temperature is equal to or higher than the phase transformation point temperature of the shape memory alloy 111. When a certain high-temperature water (usually 50 to 80 ° C.) is continuously poured by a pump or other device, the shape memory alloy 111 is caused to undergo phase transformation and is formed between adjacent soft elastic bodies 113. It is discharged out of the mold through the water holes 123 and the drain holes 124 provided in the upper base plate 117.

At this time, when the elastic modulus at high temperature of the shape memory alloy 111 is not less than five times that at low temperature as described above, the shape memory alloy 111 is compressed by the compression amount δ at low temperature. The length is extended to return to the original length (length L ₀ stored in shape) with a force of 5 times or more, and the length at that time is defined as L _h . All of the force acts as a pulling force against the presser bolt 121. However, when the presser bolt 121 is considerably thick, its elongation is so small that it can be ignored. Therefore, the elongation of the shape memory alloy 111 is the central soft elastic body. 118 and the peripheral soft elastic body 119 are respectively compressed, and the strain of the shape memory alloy 111 is accumulated in the central soft elastic body 118 and the peripheral soft elastic body 119 according to the amount of compression. At the same time, the extrusion bolt 125 fixed to the lower base plate 120 pushes up the movable ring plate 126 movably disposed at the bottom of the space formed by the inner frame 101 and the outer frame 102. That is, the space formed by the inner frame 101, the outer frame 102, and the movable ring plate 126 is changed by the movement of the movable ring plate 126, and the concrete molding object is moved upward. The central soft elastic body 118 and the peripheral soft elastic body 119 used here are made of the same material as the soft elastic body 6 shown in FIG. 1, that is, the central soft elastic body 118 and the peripheral soft elastic body 119. A material is selected that effectively accumulates strain energy generated during shape recovery (the deformed shape returns to its original shape) and has a Poisson's ratio as low as possible.

  At this time, the movable ring plate 126 is designed so that the pushing-up force can overcome the adhesion force between the molding die constituted by the inner frame 101 and the outer frame 102 and the hardened concrete, that is, the movable ring plate. The hardened fluid concrete 105 is peeled off from each contact surface of the inner frame 101 and the outer frame 102 by the thrust force of 126, that is, separated, and then the mold is turned upside down with the concrete still in place. The concrete is demolded using the means described above.

  When the push-up force of the movable ring plate 126 works, that is, when the shape memory alloy 111 starts to expand, strain energy based on shape deformation is accumulated in the central soft elastic body 118 and the peripheral soft elastic body 119. As described above, at this time, the strain energy accumulated in the soft elastic body 113 constituting the peeling moving means 103 is released.

In order to increase the push-up force of the movable ring plate 126, the initial tightening compression amount δ at the time of mold manufacture may be increased as much as possible. However, if the compression amount δ is too large, the shape memory alloy 111 exceeds the buckling or shape recovery range, and therefore it is usually within 5% of the original length L ₀ .

Thus, after the mold removal is completed, when the shape memory alloy 111 is cooled to a temperature equal to or lower than the phase transformation temperature by flowing cold water from the water inlet 122, the tensile force of the shape memory alloy 111 is 1 / 5 or less, the strain energy accumulated in the central soft elastic body 118 and the peripheral soft elastic body 119 is used, and the shape memory alloy 111 returns to the low temperature length L ₁ (= L ₀ −δ). . The relationship between the initial length L ₀ , the low temperature length L ₁ and the high temperature length L _h of the shape memory alloy 111 is L ₁ <L _h <L ₀ , and the shape memory alloy 111 is accompanied by a phase transformation. By receiving such a temperature change, a reversible shape change is expressed between L _l and L _h, and _demolding and restoration of the mold to the initial shape are performed in each cycle.

  That is, in this embodiment, the soft elastic body 113 is simply used to absorb the compression amount δ of the shape memory alloy 111.

  In the above description, the mold for producing hollow cylindrical concrete has been described. However, the present invention can be similarly applied to a mold for producing hollow rectangular concrete.

  FIG. 19 is a partial cross-sectional view of another embodiment of the mold for molding a concrete product having a hollow portion according to the present invention, and FIG. 20 is a partial cross-sectional view of FIG.

  Here, as in the case of Example 12, a molding die for producing hollow cylindrical concrete will be described.

  19 and 20 for producing hollow cylindrical concrete, utilizing the phenomenon that when the inner frame is extended in the axial direction by applying a tensile load in the axial direction of the inner frame, the inner frame is contracted in the diameter direction. A mechanism for reducing the diameter of the inner frame and removing it is provided.

  In FIG. 19, 201 is a cylindrical inner frame (core), 202 is a cylindrical outer frame arranged outside the inner frame 201, 220 is a peeling moving means arranged inside the cylinder of the inner frame 201, Reference numeral 221 denotes a shape memory alloy unit, and the peeling moving means 220 and the shape memory alloy unit 221 are configured as follows.

  A shape memory alloy unit 221 containing a round bar linear Ti—Ni-based shape memory alloy 203 is constituted by a plurality of stages as shown in FIG. 19, for example, three stages as shown in FIG. A plurality of layers, for example, three layers as shown in FIG. 19 are arranged concentrically in a form in which water passage holes 217 are formed along the outer periphery. Of the plurality of stages of shape memory alloy units 221 arranged concentrically in each layer, the uppermost shape memory alloy unit 221 is connected to the presser plate 206 via the upper water flow plate 207 and the lowermost shape memory alloy. The units 221 are in contact with the base plate 210 via the lower water flow plate 208 and the bottom plate portion 201a of the inner frame 201, respectively, and all the uppermost shape memory alloy units 221 and the uppermost shape memory alloy units 221 arranged concentrically in the respective layers. The lower-stage shape memory alloy unit 221 and the intermediate-stage shape memory alloy unit 221 are held in a form sandwiched between the presser plate 206 and the base plate 210.

  The shape memory alloy units 221 of the layers arranged concentrically along the outer periphery in the axial direction of the presser bolt 209 are concentrically for each step along the outer periphery in the axial direction of the presser bolt 209 as shown in FIG. A shape memory alloy made of steel that holds a plurality of arranged round-bar linear Ti-Ni shape memory alloys 203 and both ends of the shape memory alloys 203 in contact with each other. The tool 205 and the soft elastic body 204 arranged concentrically around the holding bolt 209 and pierced with the inner shape memory alloy 203, that is, penetrated.

  The upper water passage plate 207, the lower water passage plate 208, and the bottom plate portion 201 a of the inner frame 201 are sandwiched between the presser plate 206 and the base plate 210, and the flange portion 201 b provided on the upper end surface portion of the inner frame 201. Is attached with an initial displacement imparting nut 213b that is screwed into an initial displacement imparting bolt 213a that is rotatably provided on the presser plate 206. When the initial displacement imparting bolt 213a is rotated, the soft elastic body 204 included in each shape memory alloy unit 221 is compressed and deformed, and the tightening amount δ shown in FIG. 20 is secured. It has become.

  The mold for molding a concrete product having a hollow portion according to the present invention shown in FIGS. 19 and 20 applies a tensile load in the axial direction of the inner frame 201, that is, in the longitudinal direction (the vertical direction in FIG. 19). When the frame is extended in the longitudinal direction of the inner frame 201, the diameter of the inner frame 201 is reduced in the diameter direction of the inner frame 201 (the left-right direction in FIG. 19). is there.

  That is, in FIG. 19, the outer peripheral surface side of the inner frame 201 is a surface in contact with the concrete, but as already described, the shape memory alloy 203, the shape memory alloy holder 205, the soft elastic body A shape memory alloy unit 221 configured to accommodate 204 is disposed.

  Further, one end surface (the lower mirror portion in FIG. 19) of both end surfaces (so-called mirrors) of the inner frame 201 has a structure that is closed by the bottom plate portion 201a of the inner frame 201, and the other end surface (in FIG. 19). The upper mirror portion is formed in a structure having an open end surface so that the shape memory alloy unit 221 can be taken in and out. However, the lower closed end surface is provided with a hole for allowing the water or hot water discharge hole 211 and the presser bolt 209 to pass therethrough.

  The plurality of shape memory alloys 203 are sandwiched by shape memory alloy holders 205 from above and below with a soft elastic body 204 sandwiched in the center thereof. In this way, a plurality of shape memory alloys 203, two shape memory alloy holders 205 above and below, and one soft elastic body 204 constitute one unit, which is named the shape memory alloy unit 221 as described above. ing. The reason why the shape memory alloy 203 is limited to a predetermined length or less and is made to correspond to the total inner frame length by the plurality of shape memory alloy units 221 is that the shape memory alloy 203 has a shaft. This is because the length does not cause lateral buckling when subjected to a compressive load, that is, the critical length or less.

  As shown in FIG. 19, with the plurality of shape memory alloy units 221, the upper water flow plate 207, and the lower water flow plate 208 loaded in the cylinder of the inner frame 201, It is formed so as to ensure a required amount of gap δ (see FIG. 20) without being in close contact with the provided flange portion 201b.

  As shown in FIG. 19, the initial displacement imparting nut 213b does not rotate the initial displacement imparting bolt 213a that passes through the flange portion 201b of the inner frame 201 and the presser plate 206 provided on the upper water passage plate 207. Tighten in this way. At this time, the inner frame 201 and the initial displacement imparting bolt 213a are stretched to some extent because they are pulled. Further, the soft elastic body 204 is also subjected to compression deformation as much as the tightening amount δ, that is, the compression amount δ. At this time, strain energy corresponding to the compression deformation is accumulated in the soft elastic body 204.

  The tightening amount δ at this time is determined within a range in which the compression strain of the shape memory alloy 203 does not exceed the so-called shape recovery limit strain of the shape memory alloy 203. The flange portion 201b provided on the upper end surface portion of the presser plate 206 and the inner frame 201 under the condition that the strain generated in the shape memory alloy 203 by the tightening amount δ is equal to or less than the shape recovery limit strain of the shape memory alloy 203. FIG. 20 shows a state where the bolts are tightened so as to be in close contact with each other. The shape recovery limit strain is a unique value that varies depending on each shape memory alloy, but is about 5% in the case of a Ti-Ni type shape memory alloy.

  More specifically, FIG. 20 is a diagram showing a state where fluid concrete is poured, that is, an initial state. On the other hand, as shown in FIG. 20, the state at the time of demolding is the initial displacement imparting bolt 213a and the initial displacement imparting nut 213b so that the presser plate 206 and the flange portion 201b provided on the upper end surface portion of the inner frame 201 come into close contact with each other. In this state, the shape memory alloy unit 221 is in a high temperature state. Incidentally, FIG. 19 is only one step that passes when the mold is manufactured and assembled.

  In the initial state of the formwork shown in FIG. 20, that is, the formwork state of the tightening amount δ (the state at this time is the initial shape), fluid concrete is formed by the inner frame 201, the outer frame 202, and the like. Injected into the space.

  Referring to FIGS. 19 and 20, after a predetermined time has passed after injection of fluidized concrete, after the completion of hardening of fluidized concrete 215, the phase transformation point of shape memory alloy 203 is injected from water injection hole 214 provided in presser plate 206. When high-temperature water (usually 50 to 80 ° C.) that is higher than the temperature is continuously poured by a pump or other device, the shape memory alloy 203 is caused to undergo phase transformation and formed by adjacent shape memory alloy units 221 group. The water is discharged out of the mold through the water holes 217 and the drain holes 211 provided in the base plate 210.

  At this time, if the elastic modulus at high temperature of the shape memory alloy 203 is not less than 5 times that at low temperature as described above, the shape memory alloy 203 is compressed by the compression amount δ at low temperature. Since the shape memory alloy 203 tries to expand to return to the original length (predetermined shape memory length shown in FIG. 19) with a force of 5 times or more, as a result, The frame 201 is elongated in the axial direction (longitudinal direction) at least five times the elongation at low temperature. At the same time, strain energy corresponding to the strain is accumulated in the inner frame 201. That is, in the inner frame 201, an elongation strain of 5 times or more of the strain at a low temperature is generated and a strain energy of 5 times or more of the strain energy stored at a low temperature is stored.

  The inner frame 201 is stretched in the axial direction due to the elongation of the shape memory alloy 203, and at the same time, in the radial direction of the inner frame 201, a compressive strain of an amount obtained by multiplying the axial strain by the Poisson's ratio is generated. The Poisson's ratio is a unique value that differs depending on each material. For example, if steel is used as the material of the inner frame 201, the Poisson's ratio is usually 0.3. For example, in the case of a steel inner frame having a length of 1 m and a diameter of 300 mm, the Poisson's ratio is 0.3. Therefore, when the inner frame 201 is extended by 10 mm in the axial direction, the amount of shrinkage Δd of the inner frame 201 in the diameter direction. Δd = 0.3 × 10/1000 × 300 mm = 0.9 mm.

  The number of concentric shape memory alloy units 221 formed along the outer periphery in the axial direction of the presser bolt 209 is designed so that the amount of shrinkage in the diameter direction becomes a value necessary for demolding. Just do it. However, if the axial strain necessary for demolding exceeds the so-called elastic limit strain of the material, select another material that satisfies the conditions, or select the component size of the mold as appropriate within the allowable range. Keep it.

  In this way, after securing a gap that can be removed, a hoist or other hook is hooked on a hook hole provided in the initial displacement imparting bolt 213a and the entire inner frame 201 is pulled out. At this time, the presser bolt 209 screwed and fixed to the base plate 210 also serves as a guide and remains on the base plate 210 as it is.

  Further, the tip of the inner frame 201, that is, the lower part of the inner frame 201 shown in FIGS. 19 and 20 is formed to have a diameter slightly smaller than the upper part of the inner frame 201, that is, a tapered structure. Therefore, even if there is no shrinkage of the diameter, the mold can be removed. A spacer 212 is disposed in that portion to prevent the penetration of concrete into the outside.

  After the demolding is completed, the elastic modulus returns to the original when the temperature of the shape memory alloy 203 falls below the phase transformation point temperature. Therefore, the force for extending the inner frame 201 in the axial direction also becomes 1/5 or less. The strain energy accumulated when the inner frame 201 is subjected to elongation deformation at the time of molding is used, and the amount of elongation of the inner frame 201 also returns to the original state.

  That is, in this embodiment, the energy for returning the mold dimensions to the initial state is only the strain energy stored in the material of the inner frame 201 itself. Incidentally, the soft elastic body 204 is subjected to compressive deformation when the initial displacement δ is applied and stores strain energy. However, this energy is released when the inner frame 201 is stretched during demolding, that is, released at a high temperature. In order to use the inner frame 201 as energy for returning to the original state, the inner frame 201 must be released at a low temperature.

  Thus, a reversible shape change can be realized between the initial shape of the mold formed by the inner frame 201 and the outer frame 202 and the shape at the time of demolding only by giving a temperature change.

  In the above description, the mold for producing hollow cylindrical concrete has been described. However, the present invention can be similarly applied to a mold for producing hollow rectangular concrete.

  The soft elastic body 204 is made of the same material as the soft elastic body 6 described with reference to FIG.

  It is possible to provide a mold for molding a concrete product having a hollow portion, particularly a concrete product that requires accuracy in the hollow portion, at low cost and with high accuracy. And the mold removal operation | work at the time of manufacturing a concrete product using this shaping | molding die becomes easy, and the concrete product itself can be manufactured cheaply.

It is a top view of one Example cylinder type | mold of the shaping | molding die of concrete products which has a hollow part which concerns on this invention. It is AA sectional drawing of FIG. It is a top view of the mold for cylinders of the other Example of the shaping | molding die for concrete products which has a hollow part which concerns on this invention. It is a top view of the mold for cylinders of the other Example of the shaping | molding die for concrete products which has a hollow part which concerns on this invention. It is a fragmentary sectional view of the cylinder mold with a bottom of other examples of a mold for concrete product which has a hollow part concerning the present invention. It is a top view of the other Example square tube type | mold of the shaping | molding die for concrete products which has a hollow part which concerns on this invention. It is BB sectional drawing of FIG. It is sectional drawing of the mold for molds of the bottom of another Example of the shaping | molding die of the concrete product which has a hollow part which concerns on this invention. It is a top view of the other Example square tube type | mold of the shaping | molding die for concrete products which has a hollow part which concerns on this invention. It is CC sectional drawing of FIG. It is a deformation | transformation analysis explanatory drawing in the soft elastic body of an inner frame. It is sectional drawing of the mold for molds of the bottom of another Example of the shaping | molding die of the concrete product which has a hollow part which concerns on this invention. It is a top view of the other Example square tube type | mold of the shaping | molding die for concrete products which has a hollow part which concerns on this invention. It is DD sectional drawing of FIG. It is sectional drawing of the mold for molds of the bottom of another Example of the shaping | molding die of the concrete product which has a hollow part which concerns on this invention. It is a top view of the other Example square tube type | mold of the shaping | molding die for concrete products which has a hollow part which concerns on this invention. It is a fragmentary sectional view at the time of manufacture of another Example of the shaping | molding die for concrete products which has a hollow part which concerns on this invention, and an assembly. It is a fragmentary sectional view at the time of fluid concrete injection in FIG. It is a fragmentary sectional view at the time of manufacture of another Example of the shaping | molding die for concrete products which has a hollow part which concerns on this invention, and an assembly. It is a fragmentary sectional view at the time of fluid concrete injection in FIG.

Explanation of symbols

1, 31, 61, 101, 201 Inner frame 2, 32, 62, 102, 202 Outer frame 3, 21, 33, 63, 83, 103, 220 Peeling movement means 4, 34, 64 Shape memory alloy springs 6, 36 , 71, 113, 204 Soft elastic body 10, 40, 70 Molded object 12, 15 Inner frame slit 14, 41 Sleeve 22, 87 Shape memory alloy spring 29, 50, 80 Elastic seal for bottom plate 66 Shape memory alloy spring system 111 , 203 Shape memory alloy 221 Shape memory alloy unit

Claims (7)

For molding concrete products with a hollow part in which fluidized concrete is poured into a mold with an outer frame and an inner frame, and after the fluidized concrete has hardened, the mold is removed to produce a concrete molding. In the mold,
It is provided with a peeling movement means that engages with the inner frame, peels the concrete molding and the inner frame, and moves the inner frame from the molding,
The inner frame can be reversibly switched between the initial shape at the time of fluidized concrete injection and the shape at the time of demolding of the shape change of the inner frame due to temperature application after hardening of the fluidized concrete, from the initial shape to the shape at the time of demolding. When the shape changes, the energy storage structure having a slit for storing strain energy in the inner frame,
And a sleeve member covering at least the slit portion provided in the inner frame,
The peeling movement means is
A Ti-Ni-based shape memory alloy member that changes the inner frame from the initial shape to the shape at the time of demolding by applying temperature from the outside;
A shape memory alloy member is held, and an inner frame fastener that engages with an engaging portion formed in a slit forming portion of the inner frame is provided, and the shape change of the shape memory alloy member from the initial shape to the shape at the time of demolding The inner frame is contracted via the inner frame fastener when the shape memory alloy member is restored to the initial shape, and the shape of the inner frame is removed from the initial shape via the inner frame fastener. First holding engagement means for restoring the shape of the shape memory alloy member from the shape at the time of demolding to the initial shape by the strain energy accumulated in the inner frame at the time of the shape change to
A mold for molding a concrete product having a hollow part, characterized in that a concrete molding can be produced. For molding concrete products with a hollow part in which fluidized concrete is poured into a mold with an outer frame and an inner frame, and after the fluidized concrete has hardened, the mold is removed to produce a concrete molding. In the mold,
It is provided with a peeling movement means that engages with the inner frame, peels the concrete molding and the inner frame, and moves the inner frame from the molding,
The inner frame can be reversibly switched between the initial shape at the time of fluidized concrete injection and the shape at the time of demolding of the shape change of the inner frame due to temperature application after hardening of the fluidized concrete. When changing the shape of the energy storage structure having a slit for storing strain energy in the inner frame and a soft elastic body loaded in the slit,
The peeling movement means is
A Ti-Ni-based shape memory alloy member that changes the inner frame from the initial shape to the shape at the time of demolding by applying temperature from the outside;
A shape memory alloy member is held, and an inner frame fastening tool that engages with an engaging portion formed in a slit forming portion of the inner frame is provided, and the shape change of the shape memory alloy member from the initial shape to the shape at the time of demolding At the time, the inner frame and the soft elastic body are reduced through the inner frame fastener, and when the shape memory alloy member is restored to the initial shape, the initial position of the inner frame is reduced through the inner frame fastener. The shape of the shape memory alloy member is changed from the shape at the time of demolding to the initial shape by the strain energy accumulated in the inner frame at the time of the shape change from the shape to the shape at the time of demolding and the strain energy accumulated in the soft elastic body. First holding engagement means for restoring ,
A mold for molding a concrete product having a hollow part, characterized in that a concrete molding can be produced. For molding concrete products with a hollow part in which fluidized concrete is poured into a mold with an outer frame and an inner frame, and after the fluidized concrete has hardened, the mold is removed to produce a concrete molding. In the mold,
It is provided with a peeling movement means that engages with the inner frame, peels the concrete molding and the inner frame, and moves the inner frame from the molding,
Each of the inner frames is provided with an inner frame facing member, and has two symmetrical inner frame constituent members that should constitute the inner frame. It is possible to reversibly change the shape of the frame from the shape at the time of demolding, and at the time of the shape change from the initial shape to the shape at the time of demolding, it is disposed at the connecting portion of the two inner frame constituent members. An energy storage structure having a soft elastic body for storing strain energy;
And a sleeve member that covers at least a gap generated between the two inner frame facing members facing each other due to the soft elastic body on the outer peripheral surface of the inner frame formed by the two inner frame constituting members,
The peeling movement means is
A Ti-Ni-based shape memory alloy member that changes the inner frame from the initial shape to the shape at the time of demolding by applying temperature from the outside;
An inner frame fastening tool that holds the shape memory alloy member and engages with an engaging portion provided on each of the inner frame facing members that are arranged to face each other, from the initial shape of the shape memory alloy member The shape of the soft elastic body is reduced via the inner frame fastener when the shape is changed to the shape at the time of demolding, and the shape memory alloy member is restored via the inner frame fastener when the shape is restored to the initial shape. The shape of the shape memory alloy member is restored from the shape at the time of demolding to the initial shape by the strain energy accumulated in the soft elastic body at the time of the shape change from the initial shape of the inner frame to the shape at the time of demolding. Two holding engagement means,
A mold for molding a concrete product having a hollow part, characterized in that a concrete molding can be produced. For molding concrete products with a hollow part in which fluidized concrete is poured into a mold with an outer frame and an inner frame, and after the fluidized concrete has hardened, the mold is removed to produce a concrete molding. In the mold,
It is provided with a peeling movement means that engages with the inner frame, peels the concrete molding and the inner frame, and moves the inner frame from the molding,
The inner frame can be reversibly switched between the initial shape at the time of fluidized concrete injection and the shape at the time of demolding of the shape change of the inner frame due to temperature application after hardening of the fluidized concrete, from the initial shape to the shape at the time of demolding. When the shape changes, the energy storage structure having a soft elastic body for storing strain energy, each disposed at each coupling portion of the inner frame of the inner frame constituting member forming the inner frame,
The peeling movement means is
A Ti-Ni-based shape memory alloy member that changes the inner frame from the initial shape to the shape at the time of demolding by applying temperature from the outside;
An inner frame expansion / contraction mechanism that holds the shape memory alloy member and engages with an engagement portion provided on the inner frame and expands / contracts the side surface of each inner frame component member that forms the inner frame in a direction perpendicular to the side surface. When the shape of the shape memory alloy member changes from the initial shape to the shape upon demolding, the soft elastic body is reduced via the inner frame expansion / contraction mechanism, and the shape memory alloy member is restored to the initial shape. The shape of the shape memory alloy member is shaped at the time of demolding by the strain energy accumulated in the soft elastic body during the shape change from the initial shape of the inner frame to the shape at the time of demolding through the inner frame expansion / contraction mechanism. And a third holding engagement means for restoring the initial shape from
A mold for molding a concrete product having a hollow portion, characterized in that a concrete molding can be produced. The soft elastic body is composed of a general soft rubber, a homogeneous soft elastic body including silicone rubber, and a thin elastic metal, a net-like metal, a general purpose plastic, a reinforced plastic, a fiber, and a woven hard elastic body are combined in layers between the homogeneous soft elastic bodies. The mold for molding a concrete product having a hollow part according to any one of claims 2 to 4, wherein a layered soft elastic body or a foamed soft elastic body containing sponge rubber is used. For molding concrete products with a hollow part in which fluidized concrete is poured into a mold with an outer frame and an inner frame, and after the fluidized concrete has hardened, the mold is removed to produce a concrete molding. In the mold,
A peeling movement means for engaging the inner frame and the outer frame, peeling the concrete molding and each contact surface of the inner frame and the outer frame, and moving the molding from the inner frame and the outer frame;
The peeling movement means is
For driving the pusher that moves the movable ring plate via the pusher to move the movable ring plate that is movably disposed at the bottom of the space formed by the inner frame and the outer frame by applying temperature from the outside. Ti-Ni shape memory alloy that changes the space formed by the inner and outer frames and the movable ring plate from the initial shape to the shape at the time of demolding by inducing strain in the soft elastic body and accumulating strain energy A member,
At least two terminal alloy holders containing the shape memory alloy member in a form in which one of the ends is in contact with each other;
It is arranged between the two terminal alloy holders and penetrated in a skewered manner by the shape memory alloy member, and the two end alloy holders are extended by extension of the shape memory alloy member. A soft elastic body for compressing and deforming a pusher driving soft elastic body, and storing a strain energy corresponding to the compression deformation in the pusher driving soft elastic body;
The initial shape of the space formed by the inner and outer frames and the movable ring plate when injecting fluidized concrete, and the shape at the time of demolding that has changed shape due to temperature application after fluidized concrete hardening, while engaging with the inner and outer frames 2 is reversibly possible, strain energy is accumulated in the soft elastic body for driving the pusher due to the change in shape of the shape memory alloy member, and the pusher is driven based on the temperature change of the shape memory alloy member. With the energy storage structure that makes it possible to restore the space formed by the inner and outer frames and the movable ring plate to the initial shape of the original shape by the strain energy stored in the soft elastic body,
The initial shape of the space formed by the inner frame, the outer frame, and the movable ring plate before and after the temperature is applied to the shape memory alloy member and by the forced compression of the shape memory alloy member from the outside, and the shape at the time of demolding A mold for molding a concrete product having a hollow part, wherein the shape of the mold for molding can be changed by reversible mold deformation to produce a concrete molding. For molding concrete products with a hollow part in which fluidized concrete is poured into a mold with an outer frame and an inner frame, and after the fluidized concrete has hardened, the mold is removed to produce a concrete molding. In the mold,
It is provided with a peeling movement means that engages with the inner frame, peels the concrete molding and the inner frame, and moves the inner frame from the molding,
The peeling movement means is
Ti-Ni-based shape memory alloy member that changes the inner frame from the initial shape to the shape at the time of demolding by applying strain to the inner frame and accumulating strain energy by applying temperature from the outside, and one of both ends Are arranged between the at least two shape memory alloy holders and the two shape memory alloy holders, and penetrated in a skewered manner by the shape memory alloy members. A shape memory alloy unit comprising a soft elastic body that is compressed together with a shape memory alloy member and stores compression deformation energy when the space between the two shape memory alloy holders is compressed;
The shape memory alloy unit can be reversibly engaged with the inner frame, and can be reversibly two forms: an initial shape at the time of fluidized concrete injection and a shape at the time of demolding of the shape change of the inner frame due to temperature application after the fluidized concrete is hardened The strain energy is accumulated in the inner frame itself due to the shape change of the inner frame, and the energy that makes it possible to restore the inner frame to the initial shape by the strain energy accumulated in the inner frame itself based on the temperature change of the shape memory alloy member With a storage structure,
The shape of the mold for molding is obtained by reversible mold deformation between the initial shape of the inner frame and the shape at the time of demolding before and after applying temperature to the shape memory alloy member and by forced compression of the shape memory alloy unit from the outside. A mold for molding a concrete product having a hollow portion, characterized in that it is possible to produce a concrete molding by changing the above.

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