JPH0718641B2 - Insulation box manufacturing method - Google Patents

Description

The present invention relates to a method for manufacturing a heat insulating box in which a transparent window is arranged on one side of a wall made of foamed heat insulating material, and more specifically to a transparent window. The present invention relates to a manufacturing method when a multi-layer transparent plate is used.

2. Description of the Related Art Japanese Unexamined Patent Publication (Kokai) No. 60-165487 discloses a method of manufacturing a heat insulating box for a low temperature showcase having an opening and a protruding wall formed on one surface. In this example, the transparent window is fixed after the foamed heat insulating material is filled in the box formed by the inner and outer boxes and the breaker.

On the other hand, there is also a method of filling the foamed heat insulating material into the box body with the multilayer transparent plate fixed, but the conventional one mentioned above is to improve the circulation of the foaming concentrate before filling the foamed heat insulating material. It is generally practiced to put the box in a heating furnace and preheat it, and if it is applied to this method, it is easily expected that the multilayer transparent plate will crack at this preheating stage. It is not generally used, and at the foaming site, since the box body moves upside down and rotates, it is troublesome to handle and the glass is arranged to avoid the risk of glass breakage. The foaming in the state was not performed.

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention In the manufacturing method described in the above publication, the pressure generated by the undiluted solution of the foamed heat insulating material being foamed and solidified causes the groove portion of the breaker for disposing the transparent window, Sometimes the shape changed from its original shape and the entrance side became narrower. In this case, since it is impossible to fix the see-through window to the groove portion as it is, it is necessary to correct the groove portion before fixing, which is very cumbersome and troublesome. .

On the other hand, when filling the foam insulation into the box with the multi-layer transparent plate fixed, at the stage of preheating in the state where the box is put in the heating furnace before filling the foam insulation. There is a danger that the multi-layered transparent plate will crack, and it must be handled with care. That is, the multi-layer transparent plate has a space between each transparent plate set to about 1 mm to 10 mm in order to ensure heat insulation so that air existing in the space is not convected. Each transparent plate is not thermally deformed and cracked due to the temperature rise due to preheating, but the expansion pressure due to the temperature rise of the air sealed in the space is The vertical plate is cracked when it exceeds the allowable stress of the transparent plate determined by the lateral ratio. Therefore, in the case of this method, the temperature at the time of preheating must be suppressed to a temperature that does not exceed the allowable stress of the transparent plate, and the heating temperature is within a limited range and is suppressed. There was a problem that at a high temperature, the surrounding condition of the foaming stock solution to be filled cannot be made good and quick, and the biting on the inner surfaces of both the inner and outer boxes becomes poor and the desired heat insulating effect cannot be expected.

When the temperature was set to about 80 ° C and the foaming work was performed, the thickness of the transparent plate was 3 mm and the air layer was 6 mm, and the vertical and horizontal ratios of the transparent plate were more than 6, and the aspect ratio was 5 or less. However, if the length of the short side is about 17 cm or more, cracking occurred.

Therefore, in the present invention, a method of manufacturing an insulating box body in which cracks do not occur in the multi-layered transparent plate when the box heat-insulating body formed of the multi-layered transparent plate is filled with the foamed heat insulating material The task is to provide.

[Structure of Invention]

Means for Solving the Problems A method for manufacturing a heat insulating box according to the present invention includes a plurality of transparent plates and a heat insulating space between the transparent plates, which forms a pressure regulating path for communicating the heat insulating space with the outside. After the layer transparent plate is placed on one side wall of the box body configured by connecting both the inner and outer boxes, after heating the box body to a predetermined temperature, the box body is fixed with a heated jig. Therefore, a foamed heat insulating material is injected and filled between the two boxes to form a heat insulating box body.

The pressure regulation path formed on the transparent multi-layered plate installed on one side wall of the work box is designed when the air between the transparent plates expands due to the ambient temperature change and the internal air pressure rises. Since it acts as a ventilation path for guiding the internal air to the outside so that the internal air and the external air are in pressure equilibrium, the transparent plate is preheated during the production of the heat insulating box and fixed to the heated jig. Even if the air in the air expands, the air is guided to the outside from this pressure regulation path, and therefore the amount of deflection of each transparent plate toward the outside is suppressed, and the transparent plate is cracked. It is possible to fill the box body with the foamed insulation material without the need for repairing the box body after foaming because the multi-layer transparent plate is attached.

Embodiments Embodiments of the present invention will be described below with reference to FIGS. 1 to 7.

Reference numeral 1 is a heat-insulating box body used for displaying and selling ice cream, sorbet, etc., represented by a low-temperature showcase, and a transparent window 2 having a heater 2B for preventing dew condensation on the periphery of the upper front surface, Two front and rear sliding transparent doors 3,3 that open and close the opening in the front half are freely provided, and a door storage 4 for storing the door 3 when the transparent door 3 is opened is provided in the upper half of the upper surface. The heat insulating box body 5 is provided, and a machine room 6 is provided below the heat insulating box body 5 for arranging inevitable machine parts for cooling.

The heat-insulating box main body 5 stores the inner box with an appropriate space between the inner box 11 made of metal, for example, a hot-dip galvanized steel plate having an upper surface opened to define a storage chamber, and the upper box is opened. The outer box 12 is made of metal, for example, a hot-dip galvanized steel sheet, and the resin frame 13 is arranged across the upper ends of both boxes 11 and 12 and covers the upper opening of the space surrounded by both boxes. It is configured by foaming and filling a foam heat insulating material 14 such as rigid foamed polyurethane in the space of the box 1B. And that one wall surface (top surface in this example)
An opening 15 for putting in and taking out a product and a projecting wall 16 extending in the direction of the opening 15 are formed in.

The transparent window 2 is formed of a multi-layer transparent plate having a heat insulating space K, and in this example, two transparent glasses 2A are held by a spacer 2B at an appropriate interval, and the two glasses 2A, 2B and the spacer 2B are closely attached to each other. In order to improve the performance, both are fixed with a sealing material 2C that has adhesive properties such as thiocol, and a heater 2D for preventing condensation on the outer periphery of the sealing material 2C.
Are installed. And even if the air existing in the interval expands due to the change in ambient temperature and its pressure rises, the internal air and the external air are slightly different so that each transparent glass 2A is not cracked by the expansion pressure of the air without escape. A pressure adjusting path 2E as an air passage is formed so as to pass back and forth and to balance the pressure and to penetrate the seal material 2C from the gap portion.

The inner box 11 consists of front, back, left, right, bottom walls 11A to 11D, and a meandering low-temperature refrigerant pipe provided on the outer peripheral surface thereof, and a pipe-on-sheet type main cooler 17, A plate-shaped auxiliary cooler that is placed in the rear half of the upper surface and is formed by the so-called roll bond method and has rising pieces on the front, back, left, and right edges.
The inside 19 is cooled by 18 and. Further, the outer box 12 has a front wall 12A having an inner surface attached with a heat exchanger 20 serving as a heating element formed of a meandering refrigerant tube through which a high-temperature gas-liquid mixed refrigerant or a liquid refrigerant flows in the refrigeration cycle on an inner surface of the outer box 12, This front wall 12A
A back wall 12B having a bent side and a forward groove defined by the bent side at the upper end extending upward, and both left and right walls 12C.
And a bottom wall 12D that gently inclines rearwardly and has an injection hole for foamed heat insulating material 14 at the rear edge and an appropriate number of exhaust holes at the front edge, and front, back, left, and right rising pieces at the periphery. And an upper wall 12E located directly above the auxiliary cooler 18 and gently sloping rearward and downward, and the heat exchanger 20 prevents condensation on the front wall 12A. Even if an electric heater is arranged as the heating element instead of the heat exchanger 20, the same dew condensation preventing effect can be obtained.

The machine room 6 includes a lower part of the front wall 12A of the outer box 12, a lower part of the left and right side walls 12C, a bottom wall 12D, a first exhaust passage 21 which is vertically opened at an upper edge, and a portion lower than the first exhaust passage 21. And a removable cover 23 that forms a second exhaust passage 22 that is located in the front-rear direction and covers the opening for removing mechanical parts provided on the back surface of the heat-insulating box body 5, and the front of the outer box 12 that is located at the rear of the lower surface. Defined by a base 25 forming an intake passage 24 between the lower end of the wall 12A,
The refrigerant compressor 26, which constitutes the refrigeration cycle together with the main / auxiliary coolers 17 and 18, is fixed on the base 25, and the wire fin tube type condenser 27 is fixed to a pair of supporting members provided at both front and rear edges of the intake passage 24. is doing.

Further, the door storage portion 4 is defined by a resin shade plate 30 located on the front surface, a metal ceiling wall 31 located on the upper surface, and an upper wall 12E of the outer box 12 located on the lower surface. A lighting device (32) such as a straight tube fluorescent lamp for illuminating the inside and outside is provided, and the transparent doors (3, 3) are stored when the doors are opened.

In the frame body 13 arranged over the upper ends of both the inner and outer boxes,
Some transparent windows 2 are held and fixed in the recesses 8 formed on the front walls of both the inner and outer boxes, but in order to make the left and right parts of the square-shaped multilayer transparent plate 2 look like an arc, in this example. The first structure in which the frame body is divided into three sections and each is combined
It is composed of a frame body 13A and a second frame body 13B arranged at the front end of the protruding wall 16. Further, the first frame body 13A is divided into a left frame portion 40A and a right frame portion 40B corresponding to the left and right walls of the box body, and a front frame portion 41 corresponding to the front wall of the box body. , 40B are symmetrically configured such that they face each other.

The recess 8 is formed by surrounding the end portion by the front frame portion 41 and the connecting portion 47, and the front frame portion 41 inserts and holds the lower end of the transparent window as shown in the cross section of FIG. Forming a concave groove 42 as a groove portion for inserting and inserting the upper end of the front wall of the inner box and inserting the upper end of the front wall of the outer box into the insertion piece 43 for inserting the upper end of the front wall of the inner box. And a fixing piece 44 having a function as.

Each of the left and right frame portions 40A, 40B has an inclined portion 45 that is formed with an upward inclination toward the rear, and a dew that is formed in the front part of this inclined portion 45 and collects the dew transmitted through the inclined portion and has an opening on the lower surface. The dew receiving portion 46 formed is provided with a connecting portion 47 which is partitioned from the dew receiving portion 46 so as to project from the inclined portion so as to connect with the front frame portion 41. In this connecting portion 47,
A fixing groove 48 which communicates with the concave groove 42 and which inserts and holds the left end of the transparent window 2 and a connecting piece which digs under the fixing piece 44 of the front frame portion 41 are provided at the tip thereof and are flush with the fixing piece 44. And a decorative piece 50 acting as a window frame. The fixed groove 48
A plurality of ribs 51 are formed on the front surface of the back wall to prevent rattling before and after the transparent window. Further, the inclined portion 45 has a rail receiver 52 for holding the left and right rails 60 formed on the inner side of the upper surface, and a wiring for processing wiring for energizing electric parts such as a transparent window heater and a fluorescent lamp on the outer side of the upper surface. The processing portion 53 is formed, and the insertion piece 54 into which the upper end of the inner box is inserted is formed inside the lower surface.

Reference numeral 70 denotes a resin-made window fixing frame which inserts and holds the upper end of the transparent window 2 to fix the transparent window 2 and is covered with a hand rail 80 described later, which is arranged corresponding to the front wall of the box body. It
This window fixing frame 70 includes a receiving portion 71 that receives the lower surface of the R portion 83 of the handrail 80, a locking groove 72 that is formed at one end of the receiving portion 71 and that engages with a locking claw 86 of the handrail, and the lower surface of the receiving portion 71. The hanging piece 73 which is provided upright and has flexibility, and the opening which is formed narrower than the inside so that the upper end of the hanging window 73 can be firmly fitted and the restoring property can be provided. The window fixing groove 74 as a fixed portion and a supporting piece 75 for supporting the lower surface of the dew receiving portion 85 of the handrail 80.

80 is a front decorative frame 81 that covers the window fixing frame 70, and left and right frame parts 40
Is a metal handrail made of stainless steel or the like having excellent corrosion resistance, which is composed of left and right decorative frames 82, 82 for covering and fixing the left and right rails 60, and the front decorative frame 81 has an R portion 83 having a slant toward the front. And, per door that hangs from the rear end of R part 84
And a catch 85 and a locking claw 86 formed at the front end of the R portion,
The left and right decorative frames 82, 82 are composed of a pressing piece 87 that presses the left and right rails 60 at their inner ends, and a covering portion that covers the wiring portions of the left and right frame portions.

Next, the fixing of the transparent window 2 (multi-layer transparent plate) will be described. The inner and outer boxes 11, 12 arranged at appropriate intervals are connected to the inner and outer boxes 13 by the frame 13 formed by connection. The frame body (13) is arranged and fixed to the upper ends of both the inner and outer boxes so as to be held across. The transparent window is inserted from above so that the lower end of the transparent window 2 is retained in the concave groove 42 of the front frame portion 41 of the frame body and the left and right ends of the transparent window 2 are retained in the fixing grooves 48 of the left and right frame portions 40, respectively. To do. Thereafter, the lower end opening of the window fixing groove 74 of the window fixing frame 70 is widened against the restoring force, and the upper end of the transparent window 2 is fitted and held. then,
Suspend the left and right rails 60 on the rail receivers 52 of the left and right frame parts 40,
The left and right rails 60 of the left and right decorative frames 82, 82 of the handrail 80 are pressed and fixed respectively on the left and right rails 60, and the locking claws 86 of the front decorative frame 81 are fitted into the locking grooves 72 of the window fixing frame 70, The handrail 80 is fixed so as to cover the window fixing frame 70 and the left and right frame portions 60. With respect to both the inner and outer boxes assembled in this state, the space formed by both boxes is filled with the foamed heat insulating material to form the heat insulating box 1.

Next, filling the heat insulating box, that is, the box 1A with the foamed heat insulating material will be described with reference to FIGS. 6 and 7.

First, the inner box 11 in which the heat insulating block 90 is attached to the outer surface of the bottom wall 11D with an adhesive and the outer box 12 are connected by the frame body 13 to interpose the heat insulating block 90 and the partitioning member 91 in the space, A box body 1B is assembled in which a gap is formed between the heat insulating block and the bottom wall 12D of the outer box, and an opening 15 and a projecting wall 16 are formed on one side surface.

Then, after arranging the frame body (front frame portion) 41 having the concave groove 42 corresponding to the recess formed in the upper part of the front wall of the box body 1B so as to straddle both the inner and outer boxes 11 and 12, before this The transparent plate 2 is fitted into the concave groove 42 of the frame portion 41 to arrange the transparent plate in the recess. After this, the box
1B is transferred to the heating furnace 92 and preheated to a predetermined temperature. Next, after the box 1B is installed with the opening 15 and the protruding wall 16 as the upper surface, the nest 93 heated to a substantially constant temperature is inserted into the inner box 11 from the opening 15 and placed on the front half of the bottom wall 11D. After this, the nest 93 is slid rearward and placed right below the projecting wall 16 as shown in FIG. With the arrangement of the nests, the bottom wall 11D of the inner box inflates and bends toward the space P side due to the weight of the nest 93, while this bending causes the heat insulating block 90 to hit the bottom wall 12D of the outer box.
The gap is eliminated.

After placing the nest, keep the nest inside the inner box 11
1B is turned upside down so that the opening 15 and the protruding wall 16 are on the lower surface, and the inner and outer fixtures 95 and 96 heated to a constant temperature are used to form the box 1B.
Is stopped as shown in FIG. Nesting 93, both internal and external fixtures 95,9
The six together are called a jig. With the reversal, nesting 93
Will be added to the auxiliary cooler 18 which is the inner wall of the projecting wall 16, whereby the deflection of the bottom wall 11D of the inner box is eliminated and the heat insulating block 90 causes the bottom wall 12 of the outer box 12 to move.
A gap 94 is formed again apart from D. By injecting the undiluted foam solution Q into the space P from the injection hole 97 in this state, the undiluted solution Q grows and foams as shown by the arrow in FIG. 7, and the air in the space P is pushed out from the exhaust hole 98 and enters the space. The foamed heat insulating material layer is formed on the above to obtain the heat insulating box 1 described above.

As the resin forming the frame body 13 and the like, a material that does not melt or deform even when subjected to a predetermined temperature state during preheating is used. Also, the higher the temperature of the undiluted solution of the foam insulation material, the better and more quickly the surrounding condition becomes, and the better the biting on the inner surface of both the inner and outer boxes, the better the heating temperature at the time of preheating is as much as possible. Also, it is desirable to set the heating temperature of the jig high.

As described above, prior to the foaming work of the box body 1B, the multilayer transparent plate 2 is fixed in the groove 42 of the frame body 13A, and then the box body 1B is preheated in the heating furnace 92, and then the foam insulation material is formed. Since the stock solution Q is filled, even if the frame body 13 is pressed to the outside by the foaming pressure generated by the foaming and solidification of the stock solution Q,
The deformation is suppressed by the multilayer transparent plate 2,
The force allows the multilayer transparent plate 2 to be firmly fixed.
Also, during preheating or heating by heat transfer from the jig, the air in the heat insulating space of the multilayer transparent plate 2 expands, but this expanded air has a higher pressure than the outside air, so the pressure It is led to the outside from the pressure regulation path 2E to be balanced,
The force that pushes the transparent plate outward due to the expansion pressure of the internal air is weakened, and the amount of deflection from the inside surface of the transparent plate to the outside that accompanies this air expansion can be suppressed. The plate will not crack when heated,
At the same time when the filling and solidification of the foamed heat insulating material in the box 1B is completed, the heat insulating box with the transparent plate can be completed, and the production efficiency of the heat insulating box can be improved. The pressure regulating passage 2E may be closed after the foaming is completed.

〔The invention's effect〕

As described in detail above, according to the present invention, since the foaming work is performed in the state where the multilayer transparent plate is arranged, it is possible to manufacture the heat insulating box body with the transparent plate after the foaming is completed, Due to the presence of the transparent plate, the expansion of the box body due to the foaming and solidification can be suppressed at the transparent plate disposition site. In addition, foaming with a multi-layer transparent plate placed
Although it has been a matter of concern from the past, by forming a pressure regulating path in the transparent plate, it is possible to suppress the amount of deflection of the transparent plate due to the expansion pressure of the air in the adiabatic space of the transparent plate due to heating. Therefore, it is possible to prevent the transparent plate from cracking due to preheating.

[Brief description of drawings]

Each drawing shows an embodiment of the present invention, FIG. 1 is an enlarged sectional view of a B portion of FIG. 3, FIG. 2 is an external perspective view of a heat insulation box, and FIG. 3 is an AA sectional view of FIG. Fig. 4, Fig. 4 is an enlarged sectional view of a portion C in Fig. 1, Fig. 5 is a schematic perspective view of a frame, Fig. 6 is a sectional view of a state in which a box is transferred to a heating furnace, and Fig. 7 is a jig. It is a box cross-sectional view in the state fixed to FIG. 1 ... Insulation box, 1B ... Box, 2 ... Multi-layer transparent plate, 2E ...
… Pressure regulation path, 11 …… Inner box, 12 …… Outer box, Q …… Foam insulation, 92 …… Heating furnace, 95,96 …… Foaming jig.

Claims (1)

[Claims] 1. A multi-layered transparent plate having a plurality of transparent plates and a heat insulating space between the transparent plates and having a pressure regulating path for communicating the heat insulating space with the outside is formed by connecting both inner and outer boxes. After being placed on one side wall of the box body, the box body is heated to a predetermined temperature, then the box body is fixed by a jig heated to a predetermined temperature, and a foam insulating material is injected between the two boxes. A method for manufacturing an insulating box body, which is filled to form an insulating box body.