JP2008082612A - Heat insulating structure for wall material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a heat insulating structure for preventing the formation of a clearance and dew condensation while utilizing high heat insulating property of urethane foam materials. <P>SOLUTION: The urethane foam materials 25, 28 are held between each of inner plates 23, 26 and each of outer plates 24, 27, polystyrene foam materials 35, 36 are joined to the ends of the urethane foam materials 25, 28, respectively, and the polystyrene foam materials 35, 36 are joined to each other to join wall materials 21, 22 to each other. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a heat insulating structure of a wall material suitable for a cargo box of a freight vehicle such as a cold car.

High thermal insulation is required for the wall material constituting the cargo box (cold storage) of the cold car. Usually, this type of heat insulation wall secures its heat insulation by sandwiching a foamed urethane material made by injecting and foaming urethane resin (polyurethane resin) between an inner plate and an outer plate with a certain distance between them. .
For example, as shown in FIGS. 3 and 4, the foamed urethane material 4 on the top plate 2 side is the end portion (joint portion) of the heat insulating wall. A recess 4a is provided at the end of the side, and the end (corner) of the foamed urethane material 5 on the side wall 3 side is fitted into the recess 4a to ensure the heat insulation of the joint between the foamed urethane materials 4 and 5. ing. Therefore, as shown in FIG. 6, the inner plate 6 and the outer plate 7 are positioned at a certain distance from each other between the upper platen 41 and the lower platen 42 in the manufacturing stage of the top plate 2. A method is adopted in which the foaming mold 8 is set therebetween, and then urethane resin J is injected into a space formed between the inner plate 6, the outer plate 7 and the foaming mold 8 and foamed. The foaming mold 8 is provided with a convex portion 8a for forming the concave portion 4a. In addition, the molding surface (draft gradient 8b, 8c) of the foaming die 8 is covered with an adhesion preventing film (polypropylene film) 8d for facilitating the removal of the foaming die 8.
Thus, the heat insulation of the junction part of the said top plate 2 and the side wall 3 comes to be ensured by engaging the mutual edge part of the top plate 2 and the side wall 3 of the cold storage 1 by uneven | corrugated engagement. ing.

Japanese Utility Model Publication No. 6-20716

However, the conventional heat insulating wall made of urethane foam has the following problems. That is, as described above, for example, the foaming mold 8 is used in the manufacturing stage in order to provide the bonding recess 4a at the end of the foamed urethane material 4 on the top plate 2 side. For this reason, in consideration of mold release of the foaming mold 8, so-called drafts 8b and 8c are set in the convex portion 8a. For this reason, the end surface of the foamed urethane material 4 of the top plate 2 is formed into a slightly inclined surface rather than a right angle with respect to the inner plate 6 and the outer plate 7. Further, the upper end surface 3a of the side wall 3 is also a surface slightly inclined rather than perpendicular to the inner plate and the outer plate due to the draft angle of the foaming mold. As a result, in the state where the upper end of the foamed urethane material 5 on the side wall 3 side is joined to the end of the foamed urethane material 4 on the top plate 2 side, the draft angle of the foamed mold (mainly the foamed mold 8 is between the both 4 and 5). A slight gap 9 was generated due to draft angle 8b).
This gap 9 not only causes a decrease in the heat insulating property of the joint, but also causes condensation, which is absorbed by the foamed urethane materials 4 and 5 to reduce the heat insulating property. It becomes a cause that heat insulation falls further by 9 being expanded.
As described above, in the structure in which the urethane foam materials 4 and 5 formed by injecting and foaming the urethane resin J between the inner plate 6 and the outer plate 7 are joined to each other, the gap 9 is generated in the joint portion. Decrease in heat insulation may be a problem. This is due to the use of the foaming mold 8 in which the drafts 8b and 8c are set for the molding of the end. If the end can be formed by post-processing without using the foaming mold 8, for example, This kind of gap can be eliminated.
In this respect, as shown in FIG. 5, although it is slightly inferior in heat insulation as compared with the urethane foam materials 4 and 5, it is a polystyrene foam material (foamed polystyrene) provided as a mold material (flat plate) by ordinary extrusion molding in the market. If the resin (resin) 10, 11 is used, the joint recess 10a can be formed at right angles without providing the draft angle or the like at the end by machining, so that the inner plate 12, 13 and the outer plate can be formed. The problem of the gap 9 such as the foamed urethane material 4 can be solved by sandwiching them. Further, since the polystyrene foam material has low water absorption, even if dew condensation occurs due to the presence of a gap, the heat insulating property does not deteriorate due to this. However, when the expanded polystyrene materials 10 and 11 are used as described above, there is a problem that the heat insulating property is lower than that of the expanded urethane materials 4 and 5.
The present invention has been made in view of the above-mentioned conventional problems, and as a main heat insulating material, a foamed urethane material is used as usual, and the heat insulating property is not lowered, and a gap is generated at the joint portion. It aims at providing the heat insulation structure of a wall material which does not have.

For this reason, this invention was set as the heat insulation structure of the structure described in the claim of a claim.
According to the heat insulating structure of claim 1, as the heat insulating material sandwiched between the inner plate and the outer plate, a foamed urethane material in which a foamed polystyrene material is joined to the end portion is used, so that it is conventional. High thermal insulation can be secured. On the other hand, a polystyrene foam material is joined to the end of the urethane foam material. The expanded polystyrene material can be obtained at a low cost as a normal mold material in the market, and can be easily machined. By machining this expanded polystyrene material, it can be joined to the expanded polystyrene material of other wall materials without any gap.
From this, according to the heat insulation structure of Claim 1, it has the heat insulation of a urethane foam material, and the moldability of a polystyrene foam material, and has ensured the heat insulation of a wall material conventionally, and its junction part It is possible to maintain a high heat insulating property over a longer period of time than before.
In addition, even if a gap occurs between the expanded polystyrene materials, and condensation occurs in the gap, the expanded polystyrene material itself has a low water absorption, so that its heat insulating property does not deteriorate, and the expanded urethane material In this respect, it is possible to maintain a high heat insulating property over a long period of time.
Further, since the expanded polystyrene material can be used as a foaming mold, it is not necessary to remove the foaming mold 8 as in the prior art, and therefore the molding surface needs to be covered with an adhesion preventing film 8d in order to facilitate the demolding. Also disappear.
According to the heat insulation structure of Claim 2, it is possible to ensure a higher heat insulation property for the joint portion by fitting the expanded polystyrene materials to each other without a gap at the joint portion of both wall materials.
According to the method for producing a wall material according to claim 3, at the stage of injecting urethane resin between the inner plate and the outer plate and foaming, the polystyrene foam material is positioned and fixed between the end portions of the inner plate and the outer plate. By doing so, the polystyrene foam material can function as a mold. By using the expanded polystyrene material as it is without removing it after foaming the urethane resin, the expanded polystyrene material can be used as a joint to other wall materials. The expanded polystyrene material can be bonded to the expanded polystyrene material of other wall materials in a state without a gap by machining or the like in a state where no clearance is generated in advance. Can be joined without gaps, and thereby high heat insulation can be maintained over a long period of time.

Next, an embodiment of the present invention will be described with reference to FIGS. In this embodiment, the wall material of the cargo box (cold storage 20) of a cold storage vehicle is illustrated as a wall material which has heat insulation. FIG. 1 shows a joint between the top plate 21 and the left side wall 22 of the cool box 20. The top plate 21 is obtained by injecting a urethane resin J between an aluminum inner plate 23 and an outer plate 24 and sandwiching a foamed urethane material 25 without any gap. This is the same as in the prior art. Further, the side wall 22 is obtained by sandwiching a urethane foam material 28 formed by injecting and foaming a urethane resin J between an aluminum inner plate 26 and an outer plate 27 without any gap.
The top plate 21 and the side wall 22 are joined to each other through the retainers 30 and 31 so as to be orthogonal to each other. The retainer 30 joins the inner plate 23 of the top plate 21 and the inner plate 26 of the side wall 22 so as to be orthogonal to each other. Further, the retainer 31 joins the outer plate 24 of the top plate 21 and the outer plate 27 of the side wall 22 so as to be orthogonal to each other.
A foamed polystyrene material 35 is joined to the left end portion of the foamed urethane material 25 of the top plate 21. The expanded polystyrene material 35 is joined along the left end portion of the expanded urethane material 25. A foamed polystyrene material 36 is joined to the upper end portion of the urethane foam material 28 on the side wall 22. The expanded polystyrene material 36 is joined along the upper end portion of the expanded urethane material 28. The both foamed polystyrene materials 35 and 36 are joined to each other so that the both foamed urethane materials 25 and 28 are joined to each other at right angles.

A joint convex portion 35a is provided at the right end portion of the foamed polystyrene material 35 of the top plate 21, and the foamed urethane material 25 is placed at the right end portion of the foamed polystyrene material 35 in a state in which the foamed urethane material is filled in the joint convex portion 35a without a gap. Are firmly joined.
Further, a joint convex portion 36a is provided at the lower end portion of the foamed polystyrene material 36 on the side wall 22, and the foamed urethane material is provided at the lower end portion of the foamed polystyrene material 36 in a state where the joint convex portion 36a is filled with the foamed urethane material without a gap. 28 is firmly joined.
The expanded polystyrene material 35 on the top plate 21 side is bonded to the inner plate 23 and the outer plate 24. The expanded polystyrene material 36 on the side wall 22 side is bonded to the inner plate 26 and the outer plate 27.
A bonding recess 35b is provided on the lower surface side of the expanded polystyrene material 36 on the top plate 21 side. The joint recess 35 b is formed by machining in advance before the foamed polystyrene material 36 is bonded between the inner plate 23 and the outer plate 24. The contact surfaces 35c and 35d of the joint recess 35b are formed so as to be accurately orthogonal to each other. Further, the contact surface 35d is formed in parallel to the joint surfaces 35e and 35f for the inner plate 23 and the outer plate 24, respectively.
The corners of the expanded polystyrene material 36 on the side wall 22 side are fitted into the joint recess 35b without any gap. This corner corresponds to the joint protrusion described in the claims. Hereinafter, this corner is referred to as a joint protrusion 36b.

According to the heat insulating structure of the top plate 21 and the side wall 22 configured as described above, the foamed urethane materials 25 and 28 having high heat insulating properties for the top plate 21 and the side wall 22 are the inner plates 23 and 26 and the outer plates 24 and 27. Therefore, high heat insulation of the cool box 20 can be obtained.
In addition, a foamed polystyrene material 35 with low water absorption is joined to the left end of the foamed urethane material 25 of the top plate 21 along the left end. For this reason, it is possible to reliably prevent the urethane foam material 25 from being flooded, and in this respect, the high heat insulating property of the urethane foam material 25 can be maintained over a long period of time.
In addition, a foamed polystyrene material 36 having low water absorption is joined to the upper end portion of the foamed urethane material 28 on the side wall 22 along the upper end portion. For this reason, it is possible to reliably prevent the urethane foam material 28 from being immersed in water, and in this respect, the high heat insulating property of the urethane foam material 28 can be maintained over a long period of time.
Further, the expanded polystyrene materials 35 and 36 are usually supplied by melting and mixing a foaming agent and an additive with polystyrene, continuously extruding and foaming, etc., and supplied as a mold material at low cost, and are easily machined thereafter. be able to. Therefore, the joint recess 35b can be formed in advance on the polystyrene foam material 35 on the top plate 21 side by machining, and the contact surfaces 35c and 35d can be formed exactly at right angles to each other. In this way, a right-angled bonding recess 35b is provided in advance by machining, and thereafter it can be attached by bonding between the inner plate 23 and the outer plate 24. Therefore, the expanded polystyrene material 35 on the top plate 21 side is bonded. The joint convex part 36b of the expanded polystyrene material 36 on the side wall 22 side can be joined to the concave part 35b without any gap. According to this, since the conventional gap 9 is not generated, it is possible to prevent the occurrence of condensation, and in this respect as well, high heat insulation can be provided for a long period of time for the top plate 21 and the side wall 22 and thus the cool box 20. Can be secured.

Next, a method for manufacturing the top plate 21 will be described. As described above, the polystyrene foam material 35 is supplied in advance as a long square material. About this expanded polystyrene material 35, both the joint convex part 35a and the joint recessed part 35b are formed in advance by machining. As shown in FIG. 2, the expanded polystyrene material 35 in which the joint convex portions 35 a and the joint concave portions 35 b are formed in advance by machining is attached between the end portions of the inner plate 23 and the outer plate 24. In the case of this example, the expanded polystyrene material 35 is attached to the inner plate 23 and the outer plate 24 by adhesion.
As shown in FIG. 2, a joining edge portion 24a bent in an L shape is provided at the left end portion of the outer plate 24. In the case of this example, the expanded polystyrene material 35 is fixed at a position where a gap is provided between the joint edge 24a. As will be described later, the mold 40 is set between the expanded polystyrene material 35 and the joint edge 24a so that the expanded polystyrene material 35 is not displaced due to the foaming pressure of the urethane resin J. The mold 40 is fixed to the lower mold surface plate 42 with fixing bolts 43. The mold 40 can be detached from the lower mold surface plate 42 by loosening the fixing bolt 43.
Next, the upper platen 41 and the lower platen 42 are used to hold the inner plate 23 and the outer plate 24 at a predetermined interval, and between the inner plate 23 and the outer plate 24 and on the right side of the expanded polystyrene material 35. Urethane resin J is injected into the space and foamed. At this stage, the inner plate 23 and the outer plate 24 are fixed to each other at a constant interval. Further, as described above, by setting the mold frame 40 at the left end portion of the expanded polystyrene material 35, the expanded polystyrene material 35 can be accommodated with respect to the expansion pressure of the urethane resin J (the pressure toward the left in FIG. 1). The plate 23 and the outer plate 24 are firmly fixed so as not to be misaligned. In this way, the urethane resin J is injected between the inner plate 23 and the outer plate 24, foamed, and the foamed urethane material 25 is foam-molded. If the foamed polystyrene material 35 is pressed against the mold 40 by the foaming pressure, and as a result the mold 40 cannot be removed from between the foamed urethane material 35 and the joint edge 24a, the fixing bolt 43 is loosened. By making it possible to remove the mold 40 from the lower mold surface plate 42, the foam-molded top plate 21 can be easily taken out between the upper and lower surface plates 41, 42.
From the above, the polystyrene foam material 35 attached in advance between the inner plate 23 and the outer plate 24 functions as a foaming mold when the urethane resin J is injected and foamed. However, unlike the conventional foaming mold 8, the expanded polystyrene material 35 functioning as the foaming mold does not need to be released, and is left in an attached state. For this reason, it is not necessary to set the draft angles 8b and 8c as in the prior art on the molding surface of the expanded polystyrene material 35 (the right end surface in FIG. 2), and needless to say, the expanded urethane material 25 is replaced with the expanded polystyrene material 35. On the other hand, it is injected and foamed without gaps.

Next, the side wall 22 is also manufactured in the same procedure as the top plate 21. That is, the expanded polystyrene material 36 provided with the joint projections 36 a by machining is attached between the end portions of the inner plate 26 and the outer plate 27 by adhesion. Thereafter, the inner plate 26 and the outer plate 27 are held at a predetermined interval between the upper mold platen and the lower mold platen, and formed between the inner plate 26, the outer plate 27 and the expanded polystyrene material 36. Urethane resin J is injected into the space to be foamed. Also at this time, the polystyrene foam material 36 functions as a foaming mold. As a result, the urethane foam material 28 is filled without gaps in the joint convex portions 36a of the polystyrene foam material 36 and the recesses on both sides thereof, and the polyurethane foam material 28 is mainly disposed in the thickness direction of the polystyrene foam material 36. It will be in the state joined firmly without rattling. For this reason, as with the top plate 21, the expanded polystyrene material 36 does not need to be released and remains attached between the inner plate 26 and the outer plate 27 as it is. , 8c need not be provided.
Thus, the upper end of the side wall 22 manufactured in a separate process is joined along the left end of the top plate 21. The joint is fixed by retainers 30 and 31. That is, the retainer 30 connects the upper end portion of the inner plate 26 of the side wall 22 and the left end portion of the inner plate 23 of the top plate 21, and the upper end portion of the outer plate 27 of the side wall 22 and the left end portion of the outer plate 24 of the top plate 21. The gap is connected by a retainer 31.
At this stage, the joint convex portion 36b of the expanded polystyrene material 36 on the side wall 22 is fitted into the joint concave portion 35b of the expanded polystyrene material 35 on the top plate 21 side without any gap. As described above, the contact surface 35c and the contact surface 35d forming the joint recess 35b of the expanded polystyrene material 35 on the top plate 21 side are formed in a positional relationship that is accurately orthogonal by machining. Further, the joint convex portion 36b of the expanded polystyrene material 36 on the side wall 22 side is also accurately formed at right angles by machining in advance. For this reason, the joint convex part 36b of the expanded polystyrene material 36 on the side wall 22 side is fitted into the joint concave part 35b of the foamed polystyrene material 35 on the top plate 21 side without any gap, and accordingly, the contact surface 35c of the joint concave part 35b, The expanded polystyrene 36 on the side wall 22 side is in full contact with each of the surfaces 35d so that there is no gap.

According to the heat insulation structure of the present embodiment configured as described above, the urethane foam materials 25 and 28 are provided between the inner plates 23 and 26 and the outer plates 24 and 27 on the top plate 21 and the side wall 22 of the cold box 20. Since it is inserted, high heat insulation can be secured.
Further, since the polystyrene foam materials 35 and 36 are joined to the end portions of the urethane foam materials 25 and 28, they can be accurately joined to each other without any gaps. As a result, even if condensation occurs, the foamed polystyrene 35, 36 itself has a low water absorption, so that it is possible to prevent water from entering into the urethane foam materials 25, 28 side. The high heat insulation of 21 and the side wall 22 can be maintained over a long period of time.
In addition to the top plate 21 and the side wall 22, the right side wall and the front wall, etc. are also used for the cold insulation by the foamed urethane material sandwiched between the inner plate and the outer plate by using a wall material to which the same heat insulation structure is applied. High heat insulation can be ensured as a whole, and this high heat insulation can be maintained for a long time.
Further, since the polystyrene foam materials 35 and 36 can be used as the foaming mold for injecting and foaming the urethane foam materials 25 and 28, it is not necessary to remove the foaming mold 8 as in the prior art. The anti-adhesion film 8d for covering 8b, 8c) becomes unnecessary.

The embodiment described above can be implemented with various modifications. For example, the shape of the joint projections 35a and 36a provided on the expanded polystyrene materials 35 and 36 is not limited to the illustrated rectangle, and may be omitted depending on circumstances.
Moreover, although the joint recessed part 35b was provided in the polystyrene foam material 35 by the side of the top plate 21, and the structure which fits the joint convex part 36b of the polystyrene foam material 36 by the side wall 22 in this joint recessed part 35b was illustrated, the uneven | corrugated relationship was reversed. May be. In short, along the edge of the highly heat-insulating urethane foam material, the insulation is inferior to this, but by joining the polystyrene foam material that has low water absorption and is easy to machine, The high heat insulation property of the foamed urethane material sandwiched between the plate and the outer plate can be maintained over a long period of time, and as a result, the high heat insulation property of the cold storage or the heat storage can be maintained.
Moreover, although the wall material of the refrigerator compartment 20 of a freight vehicle was illustrated, the heat insulation which uses foaming urethane materials, such as a wall material of a stationary-type refrigerator compartment, the wall material of a fuselage used as a base station of a mobile phone, as a main heat insulating material, for example Can be widely applied to the wall. Furthermore, it can be applied not only to the cold storage but also to the wall material of the thermal storage.

It is a figure which shows embodiment of this invention, and is a longitudinal cross-sectional view of the junction part vicinity of the top plate of a cool box and a left side wall. It is a figure which shows the manufacturing method of the heat insulation wall which concerns on this invention. This figure has shown the longitudinal cross-sectional view of the left side edge part vicinity of the top plate of a cool box. It is a whole perspective view of a cool box. FIG. 4 is a sectional view taken along line (4)-(4) in FIG. 3. This figure is a structure of a conventional cool box, and shows a longitudinal sectional view of the vicinity of the joint between the top plate and the left side wall. It is a longitudinal cross-sectional view of the joint part vicinity of a top plate and a left side wall at the time of using a polystyrene foam material as a heat insulating material. It is a structure of the conventional cold storage, and is a figure which shows the manufacturing method of a top plate.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Cold storage 2 ... Top plate 3 ... Side wall (left side) 3a ... Upper end surface 4 ... Foam urethane material, 4a ... Concave part 5 ... Foam urethane material 6 ... Inner plate 7 ... Outer plate 8 ... Foam type, 8a ... Convex part 8b, 8c ... draft angle, 8d ... adhesion preventing film 9 ... gap J ... urethane resin 10, 11 ... expanded polystyrene material 20 ... cool box 21 ... top plate 22 ... side wall (left side)
23 ... Inner plate (top plate)
24 ... Outer plate (top plate), 24a ... Joining edge 25 ... Urethane foam material (top plate), 25a ... Joining recess 26 ... Inner plate (side wall)
27 ... Outer plate (side wall)
28 ... Urethane foam material (side wall), 28a ... Joint recess 30, 31 ... Retainer 35 ... Expanded polystyrene material (top plate)
35a ... Joint convex part, 35b ... Joint concave part, 35c, 35d ... Contact surface 35e, 35f ... Joint surface 36 ... Expanded polystyrene material (side wall)
36a ... Joint convex part 40 ... Form 41 ... Upper mold surface plate 42 ... Lower mold surface plate 43 ... Fixing bolt

Claims (3)

A heat insulating structure of a wall material in which a heat insulating material is sandwiched between an inner plate and an outer plate,
A wall material configured to use a foamed urethane material as the heat insulating material, and a foamed polystyrene material is joined to an end of the foamed urethane material, and the foamed polystyrene materials are joined together to join a plurality of wall materials to each other. Insulation structure. The heat insulating structure according to claim 1, wherein the two expanded polystyrene materials are bonded to one expanded polystyrene material of the two wall materials bonded to each other, and the both wall materials are bonded to each other. . A method of manufacturing a wall material in which a heat insulating material is sandwiched between an inner plate and an outer plate, wherein a polystyrene foam material is fixed between the inner plate and the outer plate, and the foamed polystyrene material and the inner plate A method of filling a foamed urethane material between the inner plate and the outer plate by injecting a urethane resin between the outer plate and foaming.

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