JP2012220149A - Heat insulation box - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heat insulation box that can easily determine whether a closed space is properly filled with foamed polyurethane resin.SOLUTION: In a closed space formed of an outer box 105 and an inner box 106, a small-space forming component 222 is provided which forms the small space communicating with the space outside the heat insulation box 102 through an air vent. The small-space forming component 222 is configured in such a manner that the foamed polyurethane resin 107 to be filled into the closed space can not enter the small space to reduce the small space with pressure by the foamed polyurethane resin 107 to be filled into the closed space, and a dielectric constant measured from outside the heat insulation box 102 changes in accordance with the size of the small space. When the filling state of the foamed polyurethane resin 107 is excellent, the small space of the small-space forming component 222 is sufficiently reduced and the dielectric constant of the small-space forming component 222 measured from outside the heat insulation box 102 corresponds to the size of the sufficiently reduced small space.

Description

  The present invention relates to a heat insulating box body in which a closed space formed by an outer box and an inner box is filled with foamed polyurethane resin.

  Conventionally, urethane foam is filled in a closed space formed by an outer box and an inner box in order to achieve both improvement in heat insulating characteristics of a heat insulating box used for a refrigerator and the like and securing strength of the box.

  The urethane foam is obtained by foaming, for example, an organic polyisocyanate, a polyol, a catalyst, a foam stabilizer, and a foaming agent (for example, see Patent Document 1).

  FIG. 3 is a schematic cross-sectional view showing the configuration of a conventional urethane foam manufacturing apparatus.

  As shown in FIG. 3, a conventional urethane foam manufacturing apparatus detects the pressure of a jig 12 in which a pressure sensor 11 is arranged and a urethane foam 13 that is injected into the jig 12 in conjunction with the pressure sensor 11. It has the detection apparatus 14, the display part 15 which displays a detected pressure value from the detection apparatus 14, and the quality determination part 16 which performs quality determination of the urethane foam 13 based on the detected pressure value.

  In addition, in the heat insulation box filled with urethane foam in the closed space formed by the outer box and the inner box, after combining the outer box and the inner box, from the inlet provided in the outer box, the organic polyisocyanate, A product in which a polyol, a catalyst, a foam stabilizer, and a foaming agent are mixed is injected into a closed space formed by the outer box and the inner box.

Japanese Patent Laid-Open No. 5-185440

  However, when determining the quality of the filled state of the urethane foam 13 based on the detected pressure value of the urethane foam 13, it is difficult to evaluate the pressure indication value when the mounting position of the pressure sensor 11 is not appropriate. In such a case, the attachment position of the pressure sensor 11 cannot be changed easily.

  Moreover, since the measurement cannot be performed after the urethane foam 13 is cured, there is a problem that it is necessary to check the internal state by destroying the structure.

  SUMMARY OF THE INVENTION The present invention solves the above-described conventional problems, and an object of the present invention is to provide a heat insulating box that can detect an unfilled state and can easily determine whether the foamed polyurethane resin is filled.

In order to solve the above problems, the heat insulating box of the present invention is a heat insulating box filled with a polyurethane foam resin in a closed space formed by an outer box and an inner box, and the inner box and the outer box At least one of them has at least one air discharge hole with a shape and size that allows air and gas generated by foaming of the foamed polyurethane resin to escape, but the foamed polyurethane resin does not leak, and A small space forming component that forms a small space that communicates with a space outside the heat insulating box through a discharge hole, and the small space forming component includes the foamed polyurethane resin filled in the closed space; The small space is reduced by the pressure of the foamed polyurethane resin that cannot enter the closed space, and the dielectric constant measured from the outside of the heat insulating box according to the size of the small space is It's configured to reduction.

  In the above configuration, if the filling state of the polyurethane foam resin is good, the small space of the small space forming component is sufficiently reduced, and the dielectric constant of the small space forming component measured from the outside of the heat insulation box is sufficiently high. The dielectric constant is in accordance with the size of the reduced small space.

  Therefore, by measuring the dielectric constant of the small space forming component from the outside of the heat insulation box filled with the polyurethane foam resin, and comparing the measured dielectric constant with a predetermined value, the unfilled state can be detected, Whether the box is filled with the expanded polyurethane resin can be determined.

  The heat insulation box of the present invention can detect an unfilled state, and can easily determine the quality of the filled state of the polyurethane foam resin.

The longitudinal cross-sectional view at the time of cutting the refrigerator which applied the heat insulation box in Embodiment 1 of this invention into right and left Sectional drawing of the small space formation components used for the heat insulation box of the embodiment Schematic sectional view showing the configuration of a conventional urethane foam manufacturing device

  1st invention is the heat insulation box body which filled the foaming polyurethane resin in the closed space formed with an outer box and an inner box, Comprising: At least any one of the said inner box and the said outer box is air and the said foam The polyurethane resin has at least one air discharge hole having a shape and a size that allows the gas generated by foaming of the polyurethane resin to escape but the foamed polyurethane resin does not leak, and the heat insulation box body is formed in the closed space via the air discharge hole. A small space forming component that forms a small space that communicates with an external space; the small space forming component does not allow the foamed polyurethane resin filled in the closed space to enter the small space; The small space is reduced by the pressure of the filled polyurethane resin to be filled, and the dielectric constant measured from the outside of the heat insulating box is changed according to the size of the small space. And features.

  In the above configuration, if the filled state of the polyurethane foam resin is good, the small space of the small space forming component is sufficiently reduced in the process of filling the polyurethane foam resin in the closed space, and is measured from the outside of the heat insulating box. The dielectric constant of the small space forming component is a dielectric constant corresponding to the size of the sufficiently reduced small space.

  Therefore, it is not necessary to disassemble the heat insulation box to determine the quality of the foamed polyurethane resin filling state of the heat insulation box, and the dielectric constant of the small space forming component is measured from the outside of the heat insulation box filled with the polyurethane foam resin. Then, by comparing the measured dielectric constant with a predetermined value, the unfilled state can be detected, and the quality of the filled state of the foamed polyurethane resin in the heat insulating box can be determined.

  The second invention is characterized in that, in the first invention, in particular, the small space forming component includes a member having a dielectric constant of 2.0 to 4.0 or 6.0 or more.

  Thereby, the precision of the quality determination of the filling state of the polyurethane foam resin of a heat insulation box can be improved.

  The third invention is characterized in that, in particular, in the first or second invention, the small space forming component is disposed in the vicinity of the final filling portion of the polyurethane foam resin.

  As a result, if the measured value indicating that the small space forming component placed near the final filling portion of the polyurethane foam resin is satisfactorily filled is obtained, the other portion is made of polyurethane foam. Since it can be inferred that the resin is satisfactorily filled, the number of small space forming parts provided in the heat insulation box and the number of inspections can be reduced, and the manufacturing cost can be reduced by rationalization.

  A fourth invention is characterized in that, in any one of the first to third inventions, the polyol used for the raw material of the foamed polyurethane resin is highly reactive and has 3 or more functional groups.

  Thereby, conventionally, since the foaming reaction of the foamed polyurethane resin is fast, the polyurethane is cured before the foamed polyurethane resin is filled into the entire heat insulating box from the fact that the viscosity increasing speed is fast, and unfilled occurs. Although there is a high possibility of producing defective products, measure the dielectric constant of small space forming parts to judge whether the foamed polyurethane resin in the heat insulation box is filled or not, and take measures to reduce defective products. Therefore, productivity can be improved using the raw material of a foaming polyurethane resin with high reactivity.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the present embodiment.

(Embodiment 1)
FIG. 1 is a longitudinal sectional view of a refrigerator to which a heat insulating box according to Embodiment 1 of the present invention is applied, cut to the left and right. FIG. 2 is a cross-sectional view of the small space forming component used in the heat insulation box of the same embodiment.

  As shown in FIG. 1, the refrigerator 101 to which the heat insulating box in the first embodiment of the present invention is applied includes a heat insulating box 102, a door 103, and a cooling means 104.

  The heat insulation box 102 includes an outer box 105 made of a steel plate or a stainless steel plate, and an inner box 106 made of a resin such as ABS, polyethylene, or polypropylene, and the closed space formed by the outer box 105 and the inner box 106 is thermally insulated. A foamed polyurethane resin 107 is filled as a material.

  The foamed polyurethane resin 107 is injected from an injection port 110 disposed at the center of the lower surface of the heat insulating box 102. In addition, in this Embodiment, although the injection port 110 was made into one place, it is not this limitation.

  At least one of the inner box 106 and the outer box 105 has an air discharge hole (not shown) with a shape and size that allows gas generated by foaming of the air and the foamed polyurethane resin 107 to escape but the foamed polyurethane resin 107 does not leak. Have.

  Further, a small space forming component 222 that forms a small space communicating with the space outside the heat insulation box 102 through the air discharge hole in the closed space is disposed near the final filling portion of the polyurethane foam resin (the heat insulation on the back surface of the heat insulation box 102). Prepare for the top of the wall.

Here, the small space forming component 222 includes a rear dielectric member 223 made of ABS resin having a dielectric constant of 2.5 and attached to the outer box 105 on the outer box 105 side of the small space, and the outer box 105. An elastic member 224 attached substantially vertically and contracted by a predetermined external force, and a front dielectric member 225 made of ABS resin having a dielectric constant of 2.5 attached to the inner box 106 side of the small space.

  In the small space forming component 222, the foamed polyurethane resin 107 filled in the closed space cannot enter the small space, and the small space is reduced by the pressure of the foamed polyurethane resin 107 filled in the closed space. The dielectric constant measured from the outside of the heat insulation box 102 changes according to the size.

  Due to the pressure when the polyurethane foam resin 107 is foamed, the small space forming component 222 is pushed in the wall thickness direction of the heat insulating wall on the back surface of the heat insulating box 102, and the rear dielectric member 223 and the front dielectric member 225 are in close contact with each other. Approach the degree.

  And the dielectric constant of the part which provided the small space formation component 222 from the back side of the heat insulation box 102 is measured. If the dielectric constant measured at this time is a value between 1.0, which is the dielectric constant of air, and 2.5, which is the dielectric constant of ABS, it can be determined that the polyurethane foam resin 107 is sufficiently filled. .

  By the way, if a highly reactive polyol having 3 functional groups is used as the raw material of the polyurethane foam resin 107, the curing time of the polyurethane foam resin 107 is shortened. However, since the polyurethane polyurethane resin 107 is cured quickly, the polyurethane foam resin 107 is closed. It is hardened before filling the entire space, causing an unfilled state and increasing the possibility of producing defective products.

  However, by measuring the dielectric constant of the small space forming component 222, it is possible to determine whether the foamed polyurethane resin 107 in the heat insulating box 102 is filled with good quality, and to deal with the reduction of defective products. Productivity can be increased by using the raw material of the polyurethane resin 107.

  In the present embodiment, the ABS resin is used, but the present invention is not limited to this.

  In the present embodiment, in order to improve the heat insulating performance of the heat insulating box 102, the vacuum heat insulating material 108 is embedded in the polyurethane foam resin 107 on the heat insulating wall on the back surface of the heat insulating box 102.

  The heat insulating box 102 has two openings at the top and bottom of the front face, and the door 103 that opens and closes the opening constitutes a storage room 109 for the upper refrigerator compartment and the lower freezer compartment.

  The door 103 can be opened and closed by rotational movement and by forward and backward movement. For example, in the case where a shelf is provided on the inner surface side of the door 103 so that the structure can be accommodated, a rotational motion is suitable, and this method is preferable for a refrigerator compartment.

  In addition, the inside of the storage chamber 109 is cooled by being supplied with cold air generated by the cooling means 104 constituting the refrigeration cycle. On the back side of the storage chamber 109, a cold air outlet and a cold air inlet are provided.

  As described above, the heat insulating box 102 according to the present embodiment is a heat insulating box 102 in which the closed space formed by the outer box 105 and the inner box 106 is filled with the polyurethane foam resin 107, At least one of the boxes 105 has at least one air discharge hole with a shape and size that allows the gas generated by foaming of the air and the foamed polyurethane resin 107 to escape but the foamed polyurethane resin 107 does not leak.

The closed space further includes a small space forming component 222 that forms a small space communicating with the space outside the heat insulating box 102 through the air discharge hole, and the small space forming component 222 is a foam filled in the closed space. The polyurethane resin 107 cannot enter the small space, and the small space is reduced by the pressure of the polyurethane foam resin 107 filled in the closed space, and the dielectric measured from the outside of the heat insulating box 102 according to the size of the small space. The rate is configured to change.

  In the above configuration, if the filled state of the foamed polyurethane resin 107 is good, the small space of the small space forming component 222 is sufficiently reduced in the process of filling the closed space with the foamed polyurethane resin 107, and the heat insulating box 102 The dielectric constant of the small space forming component 222 measured from the outside is a dielectric constant according to the size of the sufficiently reduced small space.

  Therefore, it is not necessary to disassemble the heat insulation box 102 to determine whether or not the foamed polyurethane resin 107 in the heat insulation box 102 is filled, and a small space forming component is formed from the outside of the heat insulation box 102 filled with the foam polyurethane resin 107. By measuring the dielectric constant of 222 and comparing the measured dielectric constant with a predetermined value, it is possible to detect the unfilled state, and to determine whether the filled state of the foamed polyurethane resin 107 in the heat insulating box 102 is good or bad. it can.

  In addition, if the measurement value indicating that the small space forming component 222 disposed in the vicinity of the final filling portion of the polyurethane foam resin 107 is well filled is obtained, the other portions are foamed. Since it can be estimated that the polyurethane resin 107 is satisfactorily filled, the number of small space forming parts 222 provided in the heat insulation box 102 and the number of inspections can be reduced, and the manufacturing cost can be reduced by rationalization.

  Since the heat insulation box of the present invention can detect the unfilled state and can easily determine the quality of the filled state with the foamed polyurethane resin, heat insulation in which the closed space formed by the outer box and the inner box is filled with the foamed polyurethane resin. If it uses a box, it can be applied to products other than the refrigerator.

102 Heat insulation box 105 Outer box 106 Inner box 107 Polyurethane foam resin 222 Small space forming parts

Claims (4)

A heat-insulating box body in which a closed space formed by an outer box and an inner box is filled with a polyurethane foam resin, and at least one of the inner box and the outer box is generated by foaming of air and the polyurethane foam resin. The foamed polyurethane resin has at least one air discharge hole having a shape and size that allows gas to escape but does not leak, and communicates with the space outside the heat insulating box through the air discharge hole. The small space forming component includes a small space forming component, and the small space forming component does not allow the foamed polyurethane resin filled in the closed space to enter the small space and fills the closed space. The small space is reduced by the pressure of the resin, and the dielectric constant measured from the outside of the heat insulation box changes according to the size of the small space. The box. 2. The heat insulating box according to claim 1, wherein the small space forming component has a member having a dielectric constant of 2.0 to 4.0 or 6.0 or more. The heat insulation box according to claim 1, wherein the small space forming component is disposed in the vicinity of a final filling portion of the polyurethane foam resin. The heat insulation box according to any one of claims 1 to 3, wherein a polyol used as a raw material for the foamed polyurethane resin is highly reactive and has 3 or more functional groups.