JP4327168B2 - Thermal insulation lid - Google Patents

Description

  The present invention relates to a heat insulating lid suitable for a heating container such as a cooking container or a melting container or a pan, and relates to a heat insulating lid provided with a vacuum heat insulating layer inside the lid.

  Conventionally, as this type of heat insulating lid, a lid collar portion is formed by joining the outer peripheral edges of an inner lid member and an outer lid member made of stainless steel plate, and a vacuum heat insulating layer is provided between both lid members. There is something.

  For example, a tip tube is provided at a boss portion protruding from the central portion of the outer lid member, and a vacuum heat insulating layer is provided in an internal space formed between the lid members by evacuation from the tip tube. A cap-shaped knob that covers the tip tube is fitted and fixed to the boss (see Patent Document 1).

  Here, both the lid members forming the vacuum heat insulation layer receive a pressure load in a direction of being recessed into the other side due to a pressure difference between the outside of the lid and the vacuum heat insulation layer. For this reason, when the heat insulating performance of the heat insulating lid is taken into consideration, it is necessary to prevent the inner wall surfaces of both the lid members from being in surface contact and to reduce the heat conduction between the inner lid member and the outer lid member as much as possible.

  Therefore, in the above-described heat insulating lid of Patent Document 1, a sleeve-like reinforcing member is fixed so as to be interposed between the outer lid member and the inner lid member inside the boss portion which is the central portion of the lid. The reinforcing member keeps the distance between the lid members at the center of the lid, thereby preventing the surface contact between the inner surfaces of the vacuum heat insulating layer.

JP 2004-248827 A

  However, in the heat insulating lid of the above-mentioned Patent Document 1, the reinforcing member and the outer periphery of the cover are separated as the outer periphery of the heat insulating cover is increased. Therefore, in order to prevent the surface contact, the plate thickness of both the cover members is increased. Therefore, there is a problem that the strength must be ensured and the weight of the heat insulating lid increases.

  In general, as in the above-mentioned Patent Document 1, when the outer lid member and the inner lid member are joined to each other at the outer peripheral portion, and the surface of the outer peripheral portion is a closing surface with the container side, When the flatness of the outer peripheral part of the inner lid member decreases after joining, a minute gap is created between the container side and the heat insulation lid being closed, and the minute gap becomes a heat flow path leading to the outside, and the heat insulation performance is reduced. There's a problem.

  Then, the subject of this invention is preventing the fall of the heat insulation performance, aiming at weight reduction of a heat insulation cover.

  In order to achieve the above object, the present invention provides an internal space formed between the outer lid member and the inner lid member by joining the outer lid member and the inner lid member made of a metal plate at the outer periphery of each other. In the heat insulating lid provided with a vacuum heat insulating layer, a rib portion protruding to the other side is formed on one of the outer lid member and the inner lid member, and a protruding portion that contacts the rib portion is formed on the other side. Providing the contact portion between the rib portion and the protrusion in a distributed arrangement between the lid members to prevent surface contact between the lid members in the internal space, and the plate member on which the protrusion is formed is The structure fixed to the other lid member is adopted.

In the above configuration, the rib portion protruding to the other side is formed on one of the outer lid member and the inner lid member, and the projection portion that contacts the rib portion is provided on the other side. With respect to a pressure load (approximately 98000 [Pa]), the rib portion and the protrusion serve as a support portion that keeps a distance between the outer lid member and the inner lid member. And by providing such a support portion in a distributed arrangement between both lid members, the surface contact of both lid members in the internal space is prevented, so compared with the case where the surface contact is prevented by increasing the plate thickness. The plate | board thickness of both lid members becomes thin and a heat insulation lid becomes lightweight.
In other words, the weight of one lid member does not need to be increased because only the rib portion is formed, and the weight of the other lid member is provided because the contact points between the rib portion and the protrusion are provided in a distributed arrangement. It is not necessary for the plate member to cover the other lid member entirely, and the weight can be reduced as compared with the case where the plate member can withstand the pressure load only by the plate thickness of the other lid member.
The rib portion has a higher strength than the flat plate shape, and the plate member on which the protrusion is formed has a higher strength than the flat plate shape. Therefore, in the above configuration, the rib portions and the protrusions are not easily crushed with respect to the pressure load, and an increase in the contact area between the rib portions and the protrusions is prevented. A state considered as point contact or line contact can be prevented to prevent a decrease in heat insulation performance.
Further, in the above configuration, since the plate member on which the protrusion is formed is fixed to the other lid member, a space is generated between the protrusion and the other lid member, and the other heat insulating action causes the other There is no direct heat conduction between the lid member and the rib portion, and this also prevents a decrease in heat insulation performance.

The dispersion | distribution arrangement | positioning aspect of the said contact location can be determined suitably, as long as it can prevent that the inner wall face of the both cover member which forms the said vacuum heat insulation layer can carry out surface contact.
Here, as an aspect in which the contact portion between the rib part and the protrusion is provided in a distributed arrangement between the lid members, the aspect in which the rib part is formed in series and the protrusion is provided in a distributed arrangement, Conversely, a mode in which the protrusions are provided in series, the ribs are formed in a distributed arrangement, a mode in which the ribs are formed in a distributed arrangement, and the protrusions are also provided in a distributed arrangement, which are appropriately combined. Embodiments are included.

  In addition, as an aspect in which the protrusions are provided, all the protrusions are formed on one plate member, each protrusion is formed on a separate plate member, or a plurality of protrusions are one sheet. The aspect formed in the board member and the aspect which combined these aspects suitably are contained.

  In addition, the “contact” in the above configuration refers to an aspect in which the rib portion and the protrusion are in direct contact, a state in which another member is interposed between the rib portion and the protrusion, It means that the heat conduction path between different members includes an indirect contact mode in which point contact or line contact is considered.

  Examples of the separate member include a foil member and a heat insulating fiber sheet.

Here, it is preferable to employ a configuration in which a foil member facing the other side is attached to the inner wall surface of at least one of the outer lid member and the inner lid member.
According to this configuration, when a foil member is attached to the outer lid member, heat radiation from the inner lid member is reflected to the inner lid member side by the foil member. On the other hand, when a foil member is attached to the inner lid member, heat radiation from the inner lid member is reflected by the foil member toward the inner lid member. Therefore, when the foil member is attached to the inner wall surface of at least one lid member, heat transfer to the outer lid member is reduced, so that the heat insulation performance can be further improved.

Moreover, in the said structure, it is preferable to employ | adopt the structure which used the said one cover member as the said outer cover member.
According to this configuration, the rib portion recessed into the inner lid member side is formed in the outer lid member, and the plate member is fixed to the inner lid member. Therefore, the rib portion is formed on the outer wall surface of the inner lid member. As a result, there is no recessed portion due to the formation, and the cleaning performance is improved as compared with the case where the inner lid member is formed with a rib portion that is recessed toward the outer lid member. Such a heat-insulating lid is particularly suitable for heat-insulating containers and pans such as cooking containers and melting containers that are assumed to splash and evaporate contents.

Moreover, in the said structure, it is preferable to employ | adopt the structure which provided the level | step difference along the said outer peripheral part in the said outer cover member and the said inner cover member.
In this type of heat insulating lid, in order to prevent the gas generated from the metal plate from becoming a heat medium, the outer lid member and the inner lid member made of the metal plate are evacuated while being heated after joining the outer peripheral portions. A process is performed. The outer lid member and the inner lid member are thermally expanded by the heating during the evacuation process, but both the lid members are constrained by the outer circumferential portion, so that the outer circumferential portion is deformed by the thermal expansion stress. Flatness may decrease. Such a tendency becomes more prominent as the outer periphery of the heat insulating lid is enlarged.
In this configuration, even if the thermal expansion occurs, the step wall along the outer peripheral portion falls down and is absorbed, so that the flatness of the outer peripheral portion can be prevented from being lowered. Further, since the step does not directly apply stress to the outer peripheral portion other than absorption of elongation due to thermal expansion, it is possible to prevent cracks in the joint portion.

Moreover, in the said structure, it is preferable to employ | adopt the structure which has arrange | positioned the said rib part radially using the cover center of said one cover member as a radiation center.
According to this configuration, since the rib portion is arranged radially with the center of the lid of the one lid member as a radial center, internal stress accompanying the formation of the rib portion is made uniform in the circumferential direction, and the outer peripheral portion is It becomes difficult for distortion deformation to occur, and as a result, it is possible to stabilize the joining state at the outer peripheral portions of the two lid members.
Further, according to this configuration, since the rib portion has a length in the radial direction, when closing both the lid members at the time of joining, the two portions are compared with the case where the rib portion is a dot shape. It can be easily adjusted to the contact position.

Moreover, in the said structure, it is preferable to employ | adopt the structure which made the direction which the length direction mutually crossed the said rib part and the said protrusion part.
According to this configuration, since the length directions of the two portions intersect, when the contact positions of the two portions are aligned, the misalignment tolerance width is provided in each of the two portions, and the work is facilitated.
Furthermore, according to this structure, although the said rib part and the said protrusion are line-contacted, since the direction where a length direction mutually cross | intersects, it is prevented that the contact length becomes long.
Therefore, in this configuration, it is possible to prevent the heat insulation performance from being lowered while facilitating the alignment of the rib portion and the protrusion.

Moreover, in the said structure, the upward cover can be given to the said outer cover member toward the cover center side from the outer peripheral part, and the structure which provided the upward inclination larger than the said inner cover member is employable.
According to this configuration, since the ascending slope of the outer lid member is larger than that of the inner lid member, the cross-sectional area of the outer lid member is larger than that of the inner lid member and the strength is increased. Is difficult to deform toward the inner lid member side, and the outer lid member and the inner lid member are separated as they approach the center side from the outer peripheral portion. Therefore, the surface contact can be prevented.

  As described above, according to the present invention, the outer lid member and the inner lid member made of a metal plate are joined to each other at the outer peripheral portion, and a vacuum insulation is provided in the internal space formed between the outer lid member and the inner lid member. In the heat insulating lid provided with a layer, a rib portion protruding to the other side is formed on one of the outer lid member and the inner lid member, and a protruding portion that contacts the rib portion is provided on the other side. By providing the contact portions between the ribs and the protrusions in a distributed arrangement between the cover members, the surface contact between both the cover members in the internal space is prevented, and the plate member on which the protrusions are formed is used as the other cover member. By adopting the configuration fixed to the heat insulating lid, it is possible to prevent the heat insulating performance from being lowered while reducing the weight of the heat insulating lid.

Hereinafter, the heat insulation lid concerning a 1st embodiment of this invention is explained based on an accompanying drawing.
As shown in FIG. 1 and FIG. 2, the heat insulating lid according to the first embodiment joins an outer lid member 10 and an inner lid member 20 made of a metal plate at outer peripheral portions 11 and 21, and A vacuum heat insulating layer is provided in the internal space 30 formed between the inner lid member 20 and the inner lid member 20.

  Although the stainless plate is used for the material of the outer lid member 10 and the inner lid member 20, any metal plate having a required performance may be used.

  The outer lid member 10 and the inner lid member 20 have a circular planar shape, and the outer peripheral portions 11 and 21 are joined in a state where the outer peripheral edges overlap each other. For this joining, for example, methods such as vacuum brazing, TIG welding, and seam welding can be employed.

  The outer lid member 10 and the inner lid member 20 as a whole are given an upward gradient from the outer peripheral portions 11 and 21 toward the lid center side, respectively. The ascending slope of the outer lid member 10 is larger than that of the inner lid member 20.

  The outer lid member 10 is provided with a step 12 along the outer peripheral portion 11 thereof. Further, the inner lid member 20 is provided with a step 22 along the outer periphery 21 thereof and along the inner periphery of the step 12 of the outer lid member 10.

  With the above configuration, the internal space 30 formed between the outer lid member 10 and the inner lid member 20 becomes a space in which the inner wall surfaces of the lid members 10 and 20 are separated toward the lid center side in the radial direction. Yes.

  Further, a tip tube 40 communicating with the internal space 30, a tip tube cover 41 covering the tip tube 40, and a plurality of getters 42 are fixed to the outer lid member 10. By evacuation from the tip tube 40, the internal space 30 is made into a vacuum heat insulating layer. Note that the tip tube 40 can be omitted when the outer lid member 10 and the inner lid member 20 are joined to each other at the outer peripheral portions 11 and 21 by vacuum brazing.

  The lid center portion 13 of the outer lid member 10 is formed so as to protrude from other portions, and a knob member or the like can be fitted and mounted on the outer periphery thereof.

  The cross-sectional area of the outer lid member 10 has an upward slope larger than that of the inner lid member 20, and the strength increases accordingly. Therefore, when the inner space 30 is used as a vacuum heat insulating layer, the outer lid member 10 faces the inner lid member 20 side. It is difficult to deform, and the outer lid member 10 and the inner lid member 20 are separated from the outer peripheral portions 11 and 21 as they approach the lid center side. Therefore, it is possible to prevent surface contact between the inner wall surfaces of the outer lid member 10 and the inner lid member 20 at the time of pressure load accompanying the vacuum heat insulating layer.

  Further, when the step of evacuating the outer lid member 10 and the inner lid member 20 while heating the outer lid member 10 and the inner lid member 20 is performed after the joining, the thermal expansion of both the lid members 10 and 20 outward in the radial direction 11 and the step 22 along the outer peripheral portion 21 of the inner lid member 20 are absorbed by falling outward as indicated by a two-dot chain line in FIG. Degradation can be prevented. In addition, the heating temperature at the time of said evacuation process is 300-500 degreeC, and in the case of a stainless steel plate, since the amount of radial expansion is about 2 to 3 [mm], if this amount is absorbed, Good.

  In addition, a plurality of rib portions 14 projecting toward the inner lid member 20 are formed between the lid center portion 13 and the outer peripheral portion 11 of the outer lid member 10.

  More specifically, as shown in FIG. 1, the plurality of rib portions 14 are arranged radially with the center of the lid as a radial center, and are circumferentially equidistant about 45 degrees around the center of the lid. . For this reason, the internal stress in the outer peripheral part 11 of the outer lid member 10 resulting from the formation thereof is made uniform in the circumferential direction, and a distorted minute deformation is generated in the outer peripheral part 11 to prevent its flatness from being lowered. Therefore, the joining state in the outer peripheral parts 11 and 21 of both the lid members 10 and 20 can be stabilized.

  On the other hand, the inner lid member 20 is provided with a plurality of protrusions 23a that come into contact with each other in the middle in the length direction of each rib portion 14. Due to the radial arrangement on the rib part 14 side, the contact points between the rib parts 14 and the protrusions 23a provided corresponding to the rib parts 14 are equally spaced between the center of the lid and the outer peripheral parts 11 and 21. It is distributed. Thereby, the surface contact of both the cover members 10 and 20 in the said internal space 30, ie, a vacuum heat insulation layer, is prevented.

  Here, as shown in FIG. 4, each rib part 14 is formed in the cross-section R shape. On the other hand, each protrusion 23a is formed to be in contact with the vicinity of the R apex of the rib portion 14 on a flat surface. For this reason, the rib part 14 and the protrusion 23a are substantially in a point contact state in a cross-sectional view, and the heat conduction path between the both parts 14 and 23a is minimized.

  As shown in FIGS. 1 and 5, all the protrusions 23 a are composed of rib-shaped portions formed on a circular plate member 23 having the same center as the lid center and with a 45-degree circumferentially equidistant arrangement. The plate member 23 is provided by being fixed to the inner wall surface of the inner lid member 20.

  The plate member 23 is formed with positioning holes 25 to be fitted into the two positioning projections 24 formed on the inner wall surface of the inner lid member 20, and the plate member 23 and the inner lid member in the fitted state. 20 is fixed by spot welding or the like.

  Here, in this 1st Embodiment, since each rib part 14 has length in radial direction with radial arrangement | positioning, when closing both the lid members 10 and 20 at the time of the said joining, when a rib part is dotted | punctate As compared with the above, both portions 14 and 23a can be easily adjusted to the contact position.

  Further, each protrusion 23a has a length in the circumferential direction, and each rib portion 14 has a length in the radial direction, so that the length directions thereof are substantially orthogonal to each other. For this reason, in the first embodiment, when the contact positions of both the parts 14 and 23a are aligned, the positional deviation allowable widths in the radial direction and the circumferential direction are provided for the both parts 14 and 23a, and the work becomes easy.

  Furthermore, although both the parts 14 and 23a are in line contact when considered in a plan view, their lengths are almost orthogonal, so the contact length is minimized. Therefore, in this 1st Embodiment, the fall of heat insulation performance can be prevented, aiming at the easy alignment of each rib part 14 and each protrusion 23a.

  In the first embodiment, the absorption of the radial expansion by the steps 12 and 22 coincides with the radial direction of the rib portion 14, and the protrusion 23 a comes in contact with the intermediate portion of the rib portion 14. During the process, both lid members 10 and 20 are expanded in diameter by thermal expansion, and the contact state is reliably maintained even if the rib portion 14 and the protrusion 23a are displaced.

  Moreover, each rib part 14 has higher strength than a flat plate, and the plate member 23 on which each protrusion 23a is formed has higher strength than a flat plate. Therefore, in the first embodiment, the shape of each rib portion 14 and each projection 23a is not easily crushed against the pressure load, and an increase in the contact area between each rib portion 14 and each projection 23a is prevented. The heat transfer between both the parts 14 and 23a can be maintained in a state considered to be a line contact, thereby preventing a decrease in heat insulation performance.

  Further, since the plate member 23 is an annular shape installed between the lid center and the outer peripheral portion 21, it does not cover the inner lid member 20 entirely. For this reason, in this 1st Embodiment, the inner cover member 20 can be reduced in weight compared with the case where it can endure a pressure load only with the plate | board thickness of an inner cover member. Further, the weight of the outer lid member 10 is not increased because only the rib portion 14 is formed, and the weight can be reduced compared with the case where the outer lid member 10 can withstand the pressure load only by its thickness.

  Therefore, compared with the case where the said surface contact is prevented by the increase in the plate | board thickness of both the lid members 10 and 20, the plate | board thickness of both the lid members 10 and 20 becomes thin, and a heat insulation lid | cover becomes lightweight. For example, when the diameter of the heat insulating lid is about 220 [mm] in the first embodiment, the thickness of both lid members 10 and 20 needs to be set to at least 2 mm or more when only the increase in the plate thickness is used. However, in the case of contact between the rib 14 and the protrusion 23a, the thickness can be about 0.8 to 1 mm.

  Further, each protrusion 23a is formed of a rib-shaped portion formed on the plate member 23 (see FIG. 4), and the plate member 23 is fixed to the inner lid member 20, so that each protrusion 23a and the inner lid member 20 are fixed. (See FIG. 2). Direct heat conduction does not occur between the inner lid member 20 and each rib portion 14 due to the heat insulating action of this space. For this reason, in this 1st Embodiment, the fall of heat insulation performance can be prevented.

  Further, in the first embodiment, as shown in FIGS. 2 to 5, a foil member 43 facing the other side is attached to both inner wall surfaces of the outer lid member 10 and the inner lid member 20. For this attachment, a method such as spot welding can be employed.

  In the first embodiment, a copper foil is used for the foil member 43, and the inner wall surfaces of the lid members 10 and 20 including the rib portions 14 and the protruding portions 23a are covered almost entirely. For this reason, the foil member 43 on the inner lid member 20 side radiates heat transferred from the inner lid member 20 to the outer lid member 10 side, and the foil member 43 on the outer lid member 10 side radiates the radiant heat on the inner lid member 20 side. Reflect on. On the other hand, the foil member 43 on the inner lid member 20 side reflects heat radiation from the inner lid member 20 to the inner lid member 20 side. Therefore, in this 1st Embodiment, since the heat transfer to the outer cover member 10 is reduced by reflection of both the foil members 43, heat insulation performance can be improved more.

  Moreover, in this 1st Embodiment, since the rib part 14 is formed in the outer cover member 10 side, the recessed part accompanying formation of a rib part does not exist in the outer wall surface of the inner cover member 20. As shown in FIG. For this reason, the cleaning property is better than the case where the rib portion 14 is formed on the inner lid member 20. Such a heat-insulating lid is particularly suitable for heat-insulating containers and pans such as cooking containers and melting containers that are assumed to splash and evaporate contents.

  As long as the dispersive arrangement mode of the contact portion between the rib portion 14 and the protrusion 23a can prevent the inner space 30, that is, the inner wall surfaces of the lid members 10 and 20 forming the vacuum heat insulating layer from being in surface contact, It can be determined as appropriate.

  As another example, a heat insulating lid according to a second embodiment of the present invention will be described with reference to FIGS. In the following, the description of the same configuration as in the first embodiment will be omitted and the same reference numerals will be given, and differences will be mainly described.

  As shown in FIGS. 6 and 7, in the second embodiment, the reinforcing sleeve 52 is fixed inside the lid center portion 51 of the outer lid member 50, and the distance from the inner lid member 60 is set at the center of the lid. To keep. Further, a knob portion serving as the tip tube 53 and the tip tube cover 54 is provided in the lid center portion 51. For this reason, in the second embodiment, since the vacuum exhaust is performed from the portion supported by the reinforcing sleeve 52 and the lid center portion 51, it is more reliable that the outer lid member 50 and the inner wall surface of the inner lid member 60 are in contact with each other. Can be prevented.

  Moreover, the rib part 55 of the outer cover member 50 is formed in the annular | circular shape which passes the intermediate part of radial direction. On the other hand, each protrusion 61 of the inner lid member 60 has a length in the radial direction, and is arranged so as to contact the rib portion 55 in the vicinity of the center of the length. Thereby, the contact part of the rib part 55 and the protrusion part 61 is provided by the circumferentially equally distributed arrangement | positioning between both the cover members 50 and 60, and the surface contact of the inner wall surface of both the cover members 50 and 60 is prevented. It is peeling off.

  In addition, in the said 1st Embodiment and the said 2nd Embodiment, although the rib part was formed in the outer cover member side, a rib part can also be formed in the inner cover side.

The top view of the heat insulation lid concerning a 1st embodiment (A) The expanded sectional view of the AA line shown in FIG. 1, (b) The expanded sectional view of the BB line shown in FIG. Enlarged view showing the outer periphery of the lid of FIG. The expanded sectional view of the CC line shown in FIG. The expanded sectional view of the DD line shown in FIG. The top view of the heat insulation lid concerning a 2nd embodiment The expanded sectional view of the EE line shown in FIG.

Explanation of symbols

10, 50 Outer cover member 11, 21 Outer peripheral part 12, 22 Step 13, 51 Lid center part 14, 55 Rib part 20, 60 Inner cover member 23 Plate member 23a, 61 Projection part 24 Positioning projection part 25 Positioning hole 30 Internal space 40, 53 Tip tube 41, 54 Tip tube cover 42 Getter 43 Foil member 52 Reinforcing sleeve

Claims (6)

The outer lid member and the inner lid member made of a metal plate are joined at the outer periphery of each other, and a vacuum heat insulating layer is provided in an internal space formed between the outer lid member and the inner lid member, In the heat insulating lid where the outer wall surface becomes a cleaning location, a rib portion protruding to the other side is formed on one of the outer lid member and the inner lid member, and a protrusion that contacts the rib portion is formed on the other side. And providing the contact portions between the rib portions and the projections in a distributed arrangement between the lid members to prevent surface contact of the lid members in the internal space, and the plate member with the projections formed on the other side A heat insulating lid characterized in that the one lid member is fixed to the lid member as the outer lid member .   The heat insulation lid | cover of Claim 1 which attached the foil member which faces the other side to the inner wall surface of at least one of the said outer cover member and the said inner cover member. The heat insulation lid | cover of Claim 1 or 2 which provided the level | step difference along the said outer peripheral part in the said outer cover member and the said inner cover member. The heat insulation lid | cover in any one of Claim 1 to 3 which has arrange | positioned the said rib part radially using the lid | cover center of said one lid member as a radiation center. The heat insulation lid in any one of Claim 1 to 4 which made the said rib part and the said protrusion the direction which a mutual length direction cross | intersects. The heat insulating lid according to any one of claims 1 to 5 , wherein the outer lid member is provided with an upward gradient from the outer peripheral portion toward the lid center side, and the upward gradient is provided larger than the inner lid member.

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