JP4384232B2 - Vacuum heat insulating material and refrigerator using the same - Google Patents

Description

  The present invention relates to a vacuum heat insulating material that can be used as a heat insulating material for a refrigerator that requires heat insulation, and a refrigerator using the same.

  In recent years, energy saving is strongly desired from the viewpoint of preventing global warming, and energy saving is an urgent issue for household appliances. In particular, in a refrigerator and a freezer, a heat insulating material having excellent heat insulating performance is required from the viewpoint of efficiently using heat.

  As general heat insulating materials, fiber materials such as glass wool and foams such as urethane foam are used. However, in order to improve the heat insulation of these heat insulating materials, it is necessary to increase the thickness of the heat insulating material, and there is a limit to the space that can be filled with the heat insulating material, and when space saving and effective use of the space are necessary. Is not applicable.

  Therefore, vacuum heat insulating materials have been proposed as high performance heat insulating materials. This is a heat insulating material in which a core material serving as a spacer is inserted into an outer packaging material having gas barrier properties, and the inside is reduced in pressure and sealed. As the vacuum heat insulating material, for example, as disclosed in JP-A-9-138058, a fiber material such as glass wool, which is solidified using an organic binder, is used as the core material.

  On the other hand, if the core material is a fiber material such as glass wool that is hardened using a binder, the outer packaging material may be damaged by burrs of the core material when the core material is stored in the outer packaging material. In particular, a vacuum heat insulating material that makes a core material without using a binder has also been proposed.

  This is a vacuum heat insulating material made by storing a fibrous material such as glass wool in an inner bag, compressing the inner bag, depressurizing it, and welding and sealing the opening. An example of this is JP-A-4-337195.

  By the way, when applying a vacuum heat insulating material to a heat insulating box such as a refrigerator, the foam heat insulating material formed by the outer box and the inner box is either the outer box side of the space to be filled, the inner box side, or the outer box and the inner box. Although it can arrange | position in either the intermediate | middle position with a box, actually arrange | positions in the outer box side. Specifically, a vacuum heat insulating material is often bonded to the inner surface of the outer box using an adhesive such as double-sided tape or hot melt.

  The reason why the vacuum insulation material is rarely arranged on the inner box side is that if it is arranged on the inner box side, there is a merit that the application area of the vacuum insulation material can be reduced, but the inner box is compared to the outer box. It is easy to deform and the outer surface of the inner box is uneven compared to the inner surface of the outer box, so it is difficult to firmly fix the vacuum heat insulating material to the outer surface of the inner box, and when filling with foam heat insulating material, This is because a cavity is easily formed between the heat insulating material and the inner box, and there is a problem that the inner box is deformed due to the formation of the cavity or the heat insulating performance is lowered.

JP-A-9-138058 JP-A-4-337195

  The core material made using a binder is an organic or inorganic fiber laminate, which is also solidified into a board with an organic or inorganic binder, and then cut into a fixed size by pressing or the like to form a vacuum insulation core material. However, the shape stability and handling after curing are good, but conversely, when the core material is put in the outer packaging material or when the inner packaging material is decompressed, the outer packaging material is made by the burr on the end face that can be formed during the press cutting. In addition to being damaged, the core material itself is made into a board, so there is no deformation on the core material side during decompression in the outer packaging material, and the outer packaging material is damaged due to burrs on the end surface. There was a problem of creating a tented convection space in between. In addition, the vacuum heat insulating material has a problem that it becomes a hindrance when attached to the refrigerator outer box because the vacuum heat insulating material remains warped, for example, warp or the like, which is generated when the core material is manufactured.

  The convection space was made easier as the thickness of the core became thicker and as the outer packaging material became less flexible.

  For example, if the core material is a binder, the vacuum insulation material, especially the core material, is recovered from a refrigerator collected after 10 years, and the fiber laminate used as the core material is impregnated with the binder even if it is going to be recycled. Then, there was a problem that the core material became powdery, and the particles of the powder were not constant and not suitable for reuse. That is, there has been a problem that the fiber laminate and the binder cannot be separated and taken out and it is difficult to form into a new core material.

  On the other hand, what is disclosed in Japanese Patent Application Laid-Open No. 4-337195 is a method of compressing a fibrous laminate using an interior instead of a binder, then reducing the pressure, adjusting the shape, and forming a core material. It is put into a vacuum heat insulating material.

  That is, the vacuum heat insulating material disclosed in the above Japanese Laid-Open Patent Publication No. 4-337195 is an inner member (core) in which an inorganic fiber mat is housed in an inner bag made of a plastic film, and the inner bag is compressed-depressurized-welded sealed. In addition, after the inner member (core material) is housed in the housing member (outer packaging material), the inner bag (sealing material) is hermetically sealed, and the inside of the housing member (outer packaging material) is decompressed to be welded and sealed. It is. Since it is possible to use glass wool mat for the core material for vacuum heat insulating material, it is said that the heat insulating performance can be remarkably improved as compared with the foamed pearlite powder inorganic powder and the like conventionally used as the core material. .

  In other words, the core material disclosed in the above Japanese Patent Laid-Open No. 4-337195 is not made into a board, so that a burr or the like formed on the core material at the time of cutting cannot be formed like a conventional core material. Of course, the convection space in a tent tension state between the end face of the core material and the outer packaging material is also difficult to form without any warp. Of course, there is no attention to the point of reducing the size, and there is no disclosure or suggestion about the convection space that can be produced by the ear processing of the outer packaging material.

  Also, when aluminum foil is used for the outer packaging material, it has excellent gas barrier properties, but due to the high thermal conductivity of aluminum itself, sufficient heat insulation performance cannot be obtained by heat conduction through the outer packaging material (heat bridge). There was a problem.

  This invention provides the vacuum heat insulating material which eliminated the said convection space, was excellent in heat insulation performance, made workability at the time of an earfolding easy, and was excellent in productivity, and a refrigerator using the same.

  In addition, the present invention provides a vacuum heat insulating material refrigerator with good recyclability.

  Furthermore, a binderless vacuum heat insulating material that is advantageous in terms of warping of the vacuum heat insulating material itself produced by using a core material that does not use a binder or ensuring flatness accuracy is obtained.

In order to solve the above-mentioned problems, the present invention provides a board with a binder in which a laminate of flexible inorganic fibers is housed in an inner bag and the inorganic fibers are held in a reduced pressure state with rounded ends. A synthetic resin comprising: a core material that is not hardened ; an adsorbent that is stored in a storage portion provided in the laminate of inorganic fibers; and an outer packaging material that stores the core material; and manufacturing, the outer material is depressurized therein is formed by a layer of heat-weldable synthetic resin material provided on the metal layer and an inner disposed outside the welding sealing, the ear portion of the outer material The quadruple portion where the ear portion of the inner bag is located is bent along the roundness of the end portion of the core material .

  As described above, since the ear portion of the inner bag that encapsulates the inorganic fiber laminate is positioned in the ear portion of the outer packaging material, the bend diameter always increases by the thickness of the inner bag when the ear is folded. Even if there is a foreign substance or the like in the ear, the outer packaging material will not be damaged. In addition, since the heat on the high temperature side that is carried through the heat conduction to the metal layer (for example, aluminum foil or metal vapor deposition layer) at the ear portion of the outer packaging material is partially blocked by the ear portion of the inner bag, the heat conduction amount is reduced. .

  In addition, since the inorganic fiber laminate is made of glass wool, glass fiber, alumina fiber, or silica alumina fiber, the inorganic fiber laminate can be reused and can contribute to environmental conservation. In other words, the reliability of the welding of the ear part is increased, and the airtightness is also maintained by the double bag, so that the inorganic fiber is not deteriorated due to gas intrusion or the like and the reuse is promoted.

  The inner bag is made of a polyethylene film and has a wall thickness of 15 to 50 μm. Since the inner bag needs a predetermined gas barrier property, it needs a certain thickness and is 15 μm or more. On the other hand, when it is in the outer packaging material as a vacuum heat insulating material, the thermal conductivity is higher than that of the core material, so that it can be a heat conductive layer and is 50 μm or less.

  For example, in the case of 20 μm, the overlap size of the inner bag is 40 μm, and it can be allowed up to about 40 μm of the foreign matter mixed in the inorganic fiber laminate together with the thickness of the outer packaging material, and the foreign matter can penetrate the outer packaging material. Productivity can be improved, and the ear part of the outer packaging material is not bent at a right angle by interposing the inner bag so that the inner bag is contained in the ear fold part, and at least the thickness of the inner bag is added. Therefore, the outer packaging material can be prevented from being damaged. Furthermore, a convection space in a tent tension state is not created between the inorganic fiber laminate and the inner bag during decompression.

  The inner bag has an opening for compressing the core material and degassing the inside. Therefore, it is desirable to have a thickness of 20 μm to 30 μm for stable attachment.

  Furthermore, since the above-mentioned vacuum heat insulating material is disposed in the heat insulating space formed by the outer box and the inner box, heat transfer through the conventional convection space can be suppressed, and an efficient vacuum heat insulating material. An attached refrigerator is obtained.

  ADVANTAGE OF THE INVENTION According to this invention, the vacuum heat insulating material which was excellent in heat insulation performance, made the ear folding work easy, and was excellent in productivity and recyclability, and a refrigerator using the same can be provided.

  In addition, a binderless vacuum heat insulating material that is advantageous in terms of warping of the vacuum heat insulating material itself produced by using a core material that does not use a binder or ensuring planar accuracy can be obtained.

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

  FIG. 1 is a longitudinal sectional view of a refrigerator provided with the present invention, FIG. 2 is an enlarged view of a main part of the AA cross section of FIG. 1, and FIG. 3 is for explaining the vacuum heat insulating material provided with the present invention. (A) is a vacuum heat insulating material of this invention, (b) (c) is explanatory drawing of the conventional general vacuum heat insulating material. 4A and 4B are diagrams showing the vacuum heat insulating material manufacturing process of the present invention. FIG. 4A is a diagram illustrating the present invention, FIG. 4B is an explanatory diagram of a general vacuum heat insulating material, and FIG. 5 is a vacuum heat insulating material core provided with the present invention. It is explanatory drawing for demonstrating to the manufacture process of material. FIG. 6 is an explanatory view for explaining a manufacturing process until the vacuum heat insulating material of the present invention is completed using the core material of FIG. 5, and FIG. 7 is for explaining an ear portion of the vacuum heat insulating material provided with the present invention. FIG. 8 is a diagram in which a vacuum heat insulating material is disposed in the inner box, and FIGS. 9 and 10 are diagrams for explaining the relationship between the outer packaging material and the inner bag. 11 is a view showing a state where the ear portion shown in FIG. 7 is bent, (a) is a view showing the present invention, (b) is a view showing a general vacuum heat insulating material, and FIG. 12 is a vacuum heat insulation shown in FIG. It is a figure which shows the state which has arrange | positioned the material in the heat insulation space which outer boxes and inner boxes, such as a refrigerator, form, (a) is this invention, (b) is a figure which shows the arrangement | positioning state of a general vacuum heat insulating material.

  First, in FIG. 1 and FIG. 2, the refrigerator main body 1 has a refrigerator compartment 2, a vegetable compartment 3, a first freezing compartment 4a, and a second freezing compartment 4b from the top, and the front opening of each of the above-mentioned compartments. Doors 5 to 8 are provided to close the section. 5 is a refrigerator compartment door, 6 is a vegetable compartment door, 7 is a 1st freezer compartment door, and 8 is a 2nd freezer compartment door. Thus, the doors 6 to 8 are refrigerators of a system in which the containers constituting each room are drawer-type doors and are pulled out to the near side together with the doors when the doors are pulled out. Moreover, it has a refrigeration cycle and has a compressor 9 and a cooler 10 on the back side of the freezer compartment at the back bottom of the refrigerator body 1. A cool air fan 11 is disposed above the cooler 10 to send cool air to each chamber and cool the interior to a predetermined temperature. Moreover, the compressor 9 and the cooler 10 together with a condenser (not shown) and a capillary tube (not shown) constitute a refrigeration cycle.

  The box 12 forms the outer shell of the refrigerator body 1. The box 12 includes an outer box 13, an inner box 14, a heat insulating wall 15, and the like.

  Thus, the heat insulating wall 15 is composed of the vacuum heat insulating material 16 and the foam heat insulating material 17 provided with the present invention.

  The foam heat insulating material 17 is a foam heat insulating material 17 such as an in-situ foamed urethane foam having an adhesive force. The vacuum heat insulating material 16 is made to have a higher heat insulating performance than the previous foam heat insulating material 17.

  For example, if the thermal conductivity of the foam heat insulating material 17 is about 0.016 W / mK, the thermal conductivity of the vacuum heat insulating material 16 is set to about 0.002 W / mK.

  Accordingly, assuming that the heat leak amount area of the heat insulating wall is constant, the vacuum heat insulating material having a thickness dimension of about 1/5 to 1/9 of the heat insulating wall thickness dimension formed only of the foam heat insulating material such as urethane. The amount of heat leakage from the heat insulation wall can be set at the same time. However, since the outer box 13 and the inner box 14 are not integrated in the box 12 in which the heat insulating wall is constituted only by the vacuum heat insulating material, the box strength does not satisfy the design value. The outer box 13 and the inner box 14 are bonded and integrated using a foam heat insulating material 17 such as urethane having adhesive strength. The wall thickness dimension of the foam insulation material 17 is about 5 mm to 20 mm, that is, the average thickness dimension is about 15 mm, and 5 mm or more that can be filled with the foam insulation material 17 such as urethane even in a locally thin place is secured. The strength of the box 12 is prevented from decreasing.

  Moreover, the installation position of the said vacuum heat insulating material 16 has arrange | positioned in the position which can cover intensively the place where the heat leak amount of a refrigerator is large, and has the effect. And the ratio which this vacuum heat insulating material 16 shows to the heat insulation space of a refrigerator is set to 60% or less. In other words, if the height of the box including the door at the time of installing the refrigerator is larger than its width and depth, the inside of both side walls in the height direction of the refrigerator, the inside of the back wall, and the inside of the door, respectively. Provided. The total volume of the vacuum heat insulating material is set to 60% or less of the heat insulating space volume formed by the outer box 13 and the inner box 14.

  If the total volume of the vacuum heat insulating material 16 is 60% or more of the space volume formed by the outer box 13 and the inner box 14, the foam heat insulating material 17 such as urethane foam cannot be uniformly filled, and the foam heat insulating material. A void is generated in 17 and the strength and heat insulation performance are deteriorated. Further, there is a problem that the piping of the cooler 10 and the wiring (not shown) of the cool air fan 11 may come into contact with the vacuum heat insulating material 16 and damage the vacuum heat insulating material 16.

  Next, the vacuum heat insulating material 16 provided with the present invention will be described with reference to FIG. 3, FIG. 4, FIG. 5, and FIG.

  First, in FIG. 3, the vacuum heat insulating material 16 is composed of a core material 18 and an outer packaging material 19 made of a metal foil laminate film having a plastic layer for heat welding. Thus, the core member 18 is composed of a laminate 20 of inorganic fibers and an inner bag 21. The inner bag 21 is composed of an inner bag 21 made of a polyethylene film having a thickness of 20 μm.

  Generally, natural fibers such as glass wool, glass fiber, alumina fiber, silica-alumina fiber, or cotton are used for the laminate 20 of inorganic fibers. The inner bag 21 is made of a synthetic resin film such as polyethylene having a thickness of 20 μm. The reason why the film having a thickness of 20 μm is selected is that the film has the flexibility to adsorb without forming a convection space between the inorganic fiber laminate and the end of the outer packaging material to be described later when the inner bag is decompressed. This is because the size of the foreign matter mixed in the welded portion is absorbed so that the foreign matter is not exposed from the outer packaging material.

  The core material 18 is a roll-shaped inorganic fiber laminate 20 preliminarily made to a thickness of 100 mm to 150 mm and cut into two, three or three as shown in FIGS. After folding and storing in an inner bag 21 (polyethylene synthetic resin film having a wall thickness of about 20 μm) as shown in FIG. 5B, the inorganic fiber laminate was pressed using a press 22 or the like, The inner bag 21 is compressed and then the inner bag 21 is depressurized, and then the opening of the inner bag 21 is heat-sealed and sealed using a heat welding machine 23.

  The core material thus produced becomes a vacuum heat insulating material 16 core material through a compression-decompression-welding sealing process, although a conventional binder is not used.

  That is, the core material 18 is formed in the thickness shape of the vacuum heat insulating material 16 to be made without using a binder, and can sufficiently fulfill the role of a spacer which is the mission of the core material. In addition, the core material has a certain degree of flexibility and is easy to attach to the attachment portion.

  In more detail, the inorganic fiber laminate 20 is, for example, 200 to 300 mm in the state of raw cotton before the compression step or decompression step, but is 8 to 15 mm and 20 to 25 times the thickness in the compression-decompression step. It will be compressed.

  Accordingly, the raw cotton naturally spreads in the outer circumferential direction so as to fill the gaps in the inner bag 21 during the compression.

  Next, in the decompression step, the inner bag having a thickness of about 20 μm is compressed into the core material from the outer periphery of the inorganic fiber laminate 20. In other words, the inner bag 21 is thin enough to eliminate the formation of a tent-tensioned space, that is, thin enough to be flexible (easily deformed along the shape of the stored item).

  Here, explanation of the vacuum heat insulating material generally used conventionally will be described with reference to FIGS. Reference numeral 24 denotes a vacuum heat insulating material generally used conventionally, and the vacuum heat insulating material 24 includes a core member 25. The core material 25 is formed into a plate shape having a thickness of 8 to 15 mm using a binder, and an end surface thereof is cut using a press or the like.

When the core material 25 is housed in an outer packaging material 26 (metal foil laminate film) and the inside of the outer packaging material 26 is vacuum-welded and sealed, the result is as shown in FIG. 3B or FIG. That is, FIG. 3B shows an example in which the poor flexibility of the outer packaging material 26 is achieved and the convection space 27 is formed on the end face of the core material 26. FIG. It is a figure which shows the state which 26 stuck to the core material end surface. The outer packaging material 26 is made of a plastic-metal foil laminate film. When the opening of the outer packaging material 26 is welded and sealed, the plastic portion is melted and welded.

  Here, when the vacuum heat insulating material 24 shown in FIG. 3B is used as a heat insulating wall of the refrigerator, moisture or gas generated from the fiber material or the like accumulates in the convection space 27 when used for many years and convects in the space 27. The heat is transferred. As a result, the heat insulation performance is significantly reduced.

  On the other hand, in the state shown in FIG. 3C, even if the convection space 27 cannot be formed, there is a possibility that the outer packaging material 26 hits the end face corners A and B of the core material 25 and damages the outer packaging material 26 with burrs.

  In other words, there is a high possibility that the outer packaging material is damaged at the A and B portions due to burrs or the like that are formed when the core material 25 is cut by a press or the like.

  In FIG. 3A, item number 28 indicates an adsorbent. For this adsorbent 28, for example, a molecular sieve 13x which is a synthetic zeolite is used. The adsorbent 28 adsorbs moisture and gas components emitted from the core material. That is, the core material 18 (inorganic fibers 20) is sufficiently dried before being stored in the outer packaging material 19, but it is impossible to completely remove gas and moisture due to problems such as cost. That is, it takes time to perform sufficient drying, which is impossible. For this purpose, the adsorbent 28 is put in, but the capacity of the adsorbent 28 is limited. That is, when it is incorporated in a refrigerator as a vacuum heat insulating material, it cannot be guaranteed with the adsorbent 28 for 10 years, for example. For this reason, the convection space is filled with gas and moisture as described above, and heat transfer is started by convection.

  Thus, the adsorbent 28 is filled in an adsorbent storage 29 provided in the inorganic fiber laminate 20. The inner bag 21 also serves to prevent the adsorbent 28 from jumping out of the adsorbent storage portion 29. Accordingly, the adsorbent 28 is placed in the adsorbent storage 29 before the inner bag is compressed, decompressed and welded.

  On the other hand, the item number 30 in FIGS. 3B and 3C is an adsorbent. The role of this adsorbent is the same as in FIG. However, what is shown in FIGS. 3 (b) and 3 (c) has an adsorbent 30 placed in an adsorbent storage section 31 provided in a core material 25 cured with a binder, and has an inner bag 21 as in the present invention. Since the adsorbent 30 is put in the adsorbent storage portion 31 and the inner bag 21 is not provided as in the present invention, the adsorbent 30 jumps out of the storage portion 31 and the core material 25 and the outer packaging material 26 are separated. There is a possibility of damaging the outer packaging material. For this reason, of course, it is necessary to install a means for covering the storage portion 31, for example, a lid.

  Next, the difference in the manufacturing process between the vacuum heat insulating material 16 and the conventional vacuum heat insulating material 24 will be described with reference to FIG. In the figure, (a) shows the present invention, and (b) shows a conventional example.

  First, referring to FIG. 4 (a), the production process of the vacuum heat insulating material 16 of the present invention will be described. In step 32, the roll raw cotton is cut into a predetermined size. After that, in Step 33, the raw cotton is put in a drying furnace (230 ° C.) and dried. Then, the raw cotton is stored in an inner bag, and in Step 34, temporarily compressed and packed (compression-decompression-welding sealing) is performed. Make a core material. The core material made in this state can be temporarily stored.

  Next, in step 35, the core material is accommodated in the outer packaging material. Thereafter, the inner bag is broken, and then, in step 36, the inside of the outer packaging material is depressurized, and the opening is welded and sealed and vacuum packaged.

  Thereafter, in step 37, an ear portion (described later) formed around the vacuum heat insulating material 16 is bent to one surface (for example, the upper surface) side, and the ear portion is fixed.

  The resulting vacuum heat insulating material 16 is inspected for non-defective products and defective products using a thermal conductivity checker or the like (step 38) to complete the vacuum heat insulating material 16.

  Next, in FIG. 4 (b), the manufacturing process of the conventional vacuum heat insulating material 24 shown in FIG. 4 (b) is different from FIG. 4 (a) in that a binder is used. . That is, it is a process of (binder impregnation, dehydration)-(impregnation core cutting)-(thermoforming)-(core material cutting).

  These steps are all required when a binder is used, but in the present invention, this binder is not used, but an inner bag is used instead.

  Here, the manufacturing process shown in FIG. 4 will be described with reference to FIGS.

  FIG. 5 shows the raw cotton cut from the broken line with a predetermined dimension, put in the inner bag, and the inner bag opening is welded to form the core material. FIG. 6 shows the core material 18 as the outer packaging material 19. It is the figure which showed the process of putting and making the vacuum heat insulating material 16. FIG.

  First, in FIG. 5, (a) shows a place where raw cotton wound in a roll shape is dried and then cut at, for example, a broken line portion to obtain a predetermined size, and (b) in FIG. 5 is cut at (a). It is a figure which shows the state which folded the raw cotton (inorganic fiber laminated body 20) in half, and was accommodated in the inner bag 21 formed in the bag shape by welding 3 sides. At this time, as can be seen from the figure (b), since the raw cotton 20 does not contain a curing agent such as a binder, it is deformed by utilizing its own flexibility along the shape of the inner bag 21 and the corners are rounded ( R shape).

  As shown in FIG. 5 (c), this is compressed with a press machine 22 to about 1 / 25th in the thickness direction to obtain a raw cotton 20 of 8 to 15 mm. Of course, at this time, an adsorbent (not shown) is placed in the inner bag 21.

  Next, the inside of the inner bag 21 is depressurized, and the opening of the inner bag 21 is welded and sealed with a welding machine 23. Even in this process, the raw cotton 20 fills the inner bag 21 and becomes a raw cotton 20 with rounded corners, which forms the core 18 for the vacuum heat insulating material 16 together with the inner bag 21. The core material 18 thus made becomes a very convenient core material 18 for production adjustment and the like because it can be stored in this state even without a continuous process. That is, it is kept under reduced pressure during storage.

  Next, in FIG. 6, first, in FIG. 6A, the inner bag 21 of the core material 18 accommodated in the outer packaging material 19 is prepared for decompression in the next step. ) Is broken. As a result, the pressure in the core member 18 including the inner bag 21 is smoothly reduced in FIG. 6B. At this time, it should be noted that the ear portion 21a (L4 portion) of the inner bag 21 enters the ear portion 19a (L5 portion) of the outer packaging material 19 as shown in the figure, and the ear portion 19a of the outer packaging material 19 becomes quadruple. Is a point. Originally, the inner side of the outer packaging material 19 is a heat-welded layer (plastic layer), and is formed of a synthetic resin material such as a low-density polyethylene film, a chain-like low-density polyethylene film, or a high-density polyethylene film. The compatibility with the polyethylene film of the bag 21 is good, and heat welding of the quadruple portion is possible. And the heat-welded part is integrated. Therefore, even if dust or dust falls in the opening of the outer packaging material when the core material 18 is stored, the opening absorbs dust and dust foreign matter due to the presence of the welding material (inner bag) as described above. Thus, the outer packaging material is securely sealed.

  In the vacuum heat insulating material 16 made in this way, the ear part 19a including the ear part 21a is finally folded on the upper surface side with the base of the ear part as shown in FIG. 6C, for example, with tape or the like (not shown). Fixed.

  At this time, when the ear portions 21a and 19a of the vacuum heat insulating material 16 provided with the present invention are formed, the end portion of the core member 18 is rounded, so that the ear portion 19a and the outer package are folded along the roundness. It can be folded without forming a convection space with the material 19 as in the prior art. In other words, it can be bent without worrying about the breakage of the corner B shown in FIG. This is because the inner bag 21 is prevented from being bent at right angles, which is easily damaged.

  As a result, the formation of a heat convection space, which is conventionally added to heat transfer conducted through the metal part (barrier layer) of the outer packaging material 19 of the vacuum heat insulating material 16, can be suppressed to a minimum.

  That is, since the bending diameter is always increased by the thickness of the inner bag when the ear is folded, the outer packaging material is not damaged even if there is a foreign substance or the like in the ear. In addition, since the heat on the high temperature side carried through the heat conduction of the metal layer at the ear portion of the outer packaging material is partially blocked by the inner bag, the amount of heat conduction is reduced.

  Next, with reference to FIGS. 7 and 8, the mechanism by which the heat on the outer box 13 side is conducted to the inner box 14 side by heat conduction (heat bridge) through the outer packaging material 19 will be described.

  The vacuum heat insulating material 16 itself is said to have a heat insulating performance several times that of the foam heat insulating material 17 as described above, but the outer packaging material 19, particularly the aluminum foil portion, has a small heat insulating effect.

  The heat conduction is usually referred to as heat conduction through the aluminum foil portion.

  That is, the front side aluminum foil of the outer packaging material is disposed in contact with the outer box 13 as shown in FIGS.

  Accordingly, the heat of the outer box 13 is conducted from the surface 19b on the outer box 13 side to the surface 19c on the inner box 14 side via the ear 19a as shown by the arrow in FIG. At this time, in the present invention, as shown in FIG. 7, the L2 portion is separated from the ear portion L1 by the ear portion 21a of the inner bag 21, so that the heat on the side surface 19b of the outer box 13 is heated at the A portion. The structure is not conducted to the side surface 19c.

  In other words, as the length L2 of the ear portion 21a formed by the inner bag 21 is made longer with respect to the ear portion L1 formed by the outer packaging material 19, the inner box 13 of the outer packaging material 19 than the side surface 19b of the outer casing 13 of the outer packaging material. Although the amount of heat conducted to the side surface 19c can be greatly reduced, it is preferable that L2 / L1 = 0.8 or less from the viewpoint of manufacturing.

  The outer packaging material 19 is usually formed into a bag shape by thermally welding two sheets 19b and 19c. The overlapping portion L1 up to the core material 18 including the heat welding portion L3 is referred to as an ear portion of the outer packaging material 19, and similarly, the overlapping portion L2 including the heat welding portion of the inner bag is referred to as an ear portion 21a of the inner bag 21. ing.

  And if the ear | edge part 21a of the said inner bag 21 is extended during the heat welding allowance L3 of the outer packaging materials 19b and 19c, 60 micrometers of thickness of the inner bag 21 will become a welding material, and the welding between outer packaging materials 19b and 19c will be ensured. It can be done.

  FIG. 8 is a view in which the ears 19a and 21a are bent and fixed to the side surface 19c of the inner box 13. As shown in FIG. As can be seen from the figure, the ear 19a is bent including the thickness (60 μm) of the inner bag 21 and is larger than the conventional ear bending radius (R). Can be reduced. As a result, the ear portion 19 a can be easily bent along the core member 18.

  Next, the relationship with the inner bag 21 accommodated in the outer packaging material 19 will be described with reference to FIGS.

  First, in FIG. 9, three sides are preliminarily heat-welded, and after the inner bag 21 is accommodated in the outer packaging material 19, the opening 19 d of the outer packaging material 19 is put together with the ear portion 21 a of the inner bag 21 and the ear portion 19 a of the outer packaging material 19. And heat-welded.

  The heat welded portion width W1 is welded wider than the other three heat welded portion widths W2. In other words, the ear portion 21a of the inner bag 21 is inserted into 60 to 70% of the ear portion 19a of the outer packaging material 19 as W1.

  Thus, the heat conduction through this portion is much smaller than the other three locations (W2 portion).

Next, in FIG. 10, FIG. 10 shows that the heat-welded portion W2 of the outer packaging material 19 of FIG. 9 is W3 wider than W2 after the inner bag 21 is stored.
That is, what is shown in FIG. 10 includes the ear portion 21a of the inner bag 21 and is thermally welded to obtain W3. In this case, when the outer packaging material 19 is once heat welded (W2 part in FIG. 9), the sandwich part W3 of the inner bag 21 is heat welded again. Therefore, the reliability of welding is further improved.

  The heat welding of the opening 19d for accommodating the inner bag 21 of the outer packaging material 19 is the same as that shown in FIG.

  Next, the convection space will be described with reference to FIGS.

  11 and 12 both show a comparison between the vacuum heat insulating material 16 provided with the present invention and the conventional vacuum heat insulating material 24, FIG. 11 shows a comparison of the vacuum heat insulating material 24 alone, and FIG. 12 shows a refrigerator. It shows a comparison when used as a heat insulating material.

First, in FIG. 11, since (a) of FIG. 11 is the vacuum heat insulating material 16 provided with the present invention, a convection space is provided between the inner bag 21 and the inorganic fiber laminate 20 even at the end portion. Has not occurred. Further, even if the ear portion 19a is folded as shown by a broken line, the ear portion 19a is bent along the outer packaging material without a gap so that a convection space is not formed.
If the place is a conventional vacuum heat insulating material 24, the core 25 is hardened with a binder and formed into a board, so that the end surface becomes a cut surface as shown in the figure.

  Therefore, even if the inside of the outer packaging material 26 is depressurized, a convection space 27 a is likely to be generated at the end of the core material 25. The thermal conductivity of the convection space 27 (a) is negligible while the degree of vacuum is high. However, when the space is filled with moisture or a gas coming out of the core after many years of use, the convection space 27 (a) ) The heat transferred through) exceeds the heat insulation tolerance. Further, when the ear portion 40 of the vacuum heat insulating material 24 is folded as shown in the figure, the outer packaging material 26 hits the end B of the core material 25 so as to avoid damaging with a burr formed at the time of cutting or the like. It bends like a broken line without applying. (As shown in FIG. 11A, it is not bent along the core 18) As a result, a convection space 27b is also formed in the ear fold.

  Since the convection space 27b has not been depressurized from the beginning, it naturally becomes a space for transporting heat by convection from the beginning, and cannot be said to be the vacuum heat insulating material 24 having a good heat insulating performance as a whole.

  FIG. 12 is a view showing a state in which the present invention described in FIG. 11 and the conventional vacuum heat insulating material are incorporated in the heat insulating material of the refrigerator.

  In either case, a vacuum heat insulating material is attached to the outer box 13 using hot melt or a double-sided tape 41, and then the foam heat insulating material 17 is filled.

  As for these, the ear | edge parts 19a and 40 are folded toward the inner box 14 side.

  In the vacuum heat insulating material 16 of the present invention, since the convection spaces 27a and 27b are not formed, there is no heat transfer through the convection spaces 27a and 27b, so heat transfer through the metal portion of the outer packaging material is sufficient. In the conventional vacuum heat insulating material 24, in addition to the heat transfer through the metal part of the outer packaging material 26, the convection spaces 27a and 27b must be passed to prevent the heat on the outer box 13 side from entering the inner box 14 side. I had to. Conventionally, measures have been taken by increasing the wall thickness of the foam heat insulating material 17 as a means for this purpose.

  In the present invention, as described above, a laminate of inorganic fibers is placed in a circular bag, and the inner bag is temporarily compressed, decompressed, welded and sealed, and the inner fiber has a laminate of inorganic fibers without gaps. A vacuum insulation material made by placing the core material made by using the inside of the outer packaging material made of metal foil laminate film, etc., breaking the sealing of the inner bag, reducing the pressure inside the outer packaging material, and welding and sealing However, since the ear part of the inner bag encapsulating the inorganic fiber laminate is positioned in the ear part of the outer packaging material, when the ear is folded, the folding diameter is always increased by the thickness of the inner bag. Of course, there is no damage to the outer packaging material even if there is a foreign object, etc., and the heat on the high temperature side that is carried through the heat conduction of the metal foil, such as aluminum foil, is partly by the inner bag at the ear of the outer packaging material. Since it is interrupted, the amount of heat conduction is reduced.

  In addition, the inner bag is welded because the inner bag ears are located at the opening welded part of the outer packaging material, and the thickness after welding is thicker than other welded parts. In addition to facilitating the welding of the outer packaging material, it absorbs foreign matters such as dust and dust as the welding material becomes thicker, so that a reliable welding and sealing can be achieved.

  In addition, since the inorganic fiber laminate is made of glass wool, glass fiber, alumina fiber, silica alumina fiber or the like, the laminate of inorganic fiber can be reused and can contribute to environmental conservation. That is, the reliability of the ear welding is increased, the hermeticity maintenance is further improved, the inorganic fiber is not deteriorated by gas intrusion or the like, and the reuse is promoted.

  The inner bag is made of a heat-sealable synthetic resin and has a thickness of 20 to 50 μm. When the thickness is 20 μm, the size of the foreign matter mixed in the inorganic fiber laminate is up to 40 μm. In the case of a wall thickness of 50 μm, it is acceptable up to 100 μm, and not only can productivity be improved, but also a convection space in a tent tension state is not created between the inorganic fiber laminate and the inner bag at the time of decompression. .

  Furthermore, in the refrigerator which arrange | positions a vacuum heat insulating material in the heat insulation space formed by an outer box and an inner box, The said vacuum heat insulating material is a vacuum heat insulating material in any one of Claims 1-4. Since it is a certain refrigerator, heat transfer through the conventional convection space can be suppressed, and an efficient refrigerator with a vacuum heat insulating material can be obtained.

It is a longitudinal cross-sectional view of the refrigerator of a present Example. It is principal part AA cross-section enlarged view of FIG. It is comparative explanatory drawing of the vacuum heat insulating material of a present Example, and the conventional vacuum heat insulating material. It is explanatory drawing of the manufacturing process of the vacuum heat insulating material of a present Example, and the conventional vacuum heat insulating material. It is manufacturing process explanatory drawing of a core material. It is manufacturing process explanatory drawing of a vacuum heat insulating material. It is explanatory drawing of the ear | edge part of a vacuum heat insulating material. It is the figure which has arrange | positioned the vacuum heat insulating material in the inner box. It is a figure explaining the relationship between an outer packaging material and an inner bag. It is a figure explaining the example different from FIG. It is comparison explanatory drawing of an ear | edge part bending state. It is comparative explanatory drawing which shows the refrigerator arrangement | positioning state of a vacuum heat insulating material.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Refrigerator main body 2 ... Refrigeration room 3 ... Vegetable room 4a ... 1st freezer room 4b ... 2nd freezer room 5 ... Cold room door 6 ... Vegetable room door 7 ... Door of 1st freezer room 8 ... 2nd freezer room 9 ... Compressor 10 ... Cooler 11 ... Cooling fan 12 ... Box 13 ... Outer box 14 ... Inner box 15 ... Insulating wall 16 ... Vacuum insulation 17 ... Foamed insulation 18 ... Core 19 ... Outer packaging 19a ... Ear
DESCRIPTION OF SYMBOLS 20 ... Laminated body of inorganic fiber 21 ... Inner bag 21a ... Ear part 22 ... Press machine 23 ... Thermal welding machine 24 ... Conventional vacuum heat insulating material 25 ... Core material 26 ... Outer packaging material 27 ... Convection space (a) (b)
28 ... Adsorbent 29 ... Adsorbent storage unit 30 ... Adsorbent (FIGS. 3B and 3C) 31 ... Adsorbent storage unit 32 ... Step 32 33 ... Step 33 34 ... Step 34 35 ... Step 35 36 ... Step 36 37 ... Step 37 38 ... Step 38 39 ... Step 39 40 ... Ear part of conventional vacuum heat insulating material 41 ... Hot melt or double-sided tape

Claims (4)

A core material which is not hardened into a board with a binder in which a laminate of flexible inorganic fibers is housed in an inner bag and the inorganic fibers are held under a reduced pressure in a reduced pressure state, and the inorganic fibers An adsorbent housed in a housing portion provided in the laminate and an outer packaging material for housing the core material, the inner bag is made of a heat-sealable synthetic resin, and the outer packaging material is provided outside. A quadruple portion formed of a metal layer and a layer of heat- sealable synthetic resin material provided on the inner side, the inside of which is decompressed and welded and sealed, and the ear portion of the inner bag is positioned in the ear portion of the outer packaging material Is bent along the roundness of the end of the core material. In claim 1,
A vacuum heat insulating material made of glass wool, glass fiber, alumina fiber, or silica-alumina fiber as the laminate of inorganic fibers. In claim 1 or 2,
A vacuum heat insulating material in which the inner bag is made of a heat-weld synthetic resin and has a thickness of 15 to 50 μm. In the refrigerator formed by arranging the vacuum heat insulating material in the insulation space formed by the outer box and the inner box, the vacuum insulation material, laminates of inorganic fibers having a flexibility is housed inside the inner bag inorganic fibers A core material that is not hardened into a board shape with a binder that is held in a rounded state at a reduced pressure, an adsorbent that is stored in a storage part provided in the laminate of inorganic fibers, and the core material The inner bag is made of a heat-sealable synthetic resin, and the outer bag is made of a metal layer provided on the outside and a layer of heat-sealable synthetic resin material provided on the inside. is formed by decompressing the inside are welded sealed, and characterized in that the quadruple of the ear portion was positioned within said bag to the ear portion of the outer material is folded along the rounded end of the core member Refrigerator.

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