EP3530502B1

EP3530502B1 - Electric heater in air conditioner for vehicle, and method for manufacturing same

Info

Publication number: EP3530502B1
Application number: EP17881949.6A
Authority: EP
Inventors: Takehiro Yamamoto; Naoki Yamamoto
Original assignee: Japan Climate Systems Corp
Current assignee: Japan Climate Systems Corp
Priority date: 2016-12-13
Filing date: 2017-11-15
Publication date: 2020-08-19
Anticipated expiration: 2037-11-15
Also published as: EP3530502A4; EP3530502A1; WO2018110192A1; CN109982880A; JP6936575B2; JP2018095074A

Description

TECHNICAL FIELD

The present invention relates to a structure of an electric heater provided to an air conditioner for a vehicle that is installed in an automobile, for example, and a method for manufacturing the electric heater, and particularly belongs to a technical field for a structure including a fin that transmits heat generated by a heating body supplied with electric power to air to be air-conditioned.

BACKGROUND ART

Conventionally, there have been cases in which an electric heater configured to heat air to be air-conditioned is provided to an air conditioner for a vehicle, for example (see Patent Documents 1 and 2, for example). Such an electric heater includes: PTC elements and fins for dissipating heat that are stacked; and a spring element for compressing the PTC elements and the fins in the stacking direction. The PTC elements, the fins, and the spring element are held by a holding frame in a stacked manner.
In each of Patent Documents 1 and 2, a plurality of struts are provided that extend from an upper-peripheral portion of the holding frame to a lower-peripheral portion thereof to connect between the upper-peripheral portion and the lower-peripheral portion. The struts extend straight in the vertical direction, and are disposed in an evenly spaced manner in the width direction of the holding frame. Air to be air-conditioned passes through inside of the holding frame, and is heated by heat of the PTC elements while passing through the fins.
The holding frame in each of Patent Documents 1 and 2 includes an upper housing and a lower housing that are split into two in the flow direction of outside air. When the electric heater in each of Patent Documents 1 and 2 is manufactured, the PTC elements and the fins are stacked to be assembled in advance to the upper housing first in a stacked manner. In this state, when the lower housing is assembled to the upper housing, the spring element is pushed into the upper housing, whereby compression force is applied to the PTC elements and the fins in the stacking direction. By assembling the lower housing to the upper housing, the PTC elements and the fins are held from both sides in the flow direction of outside air, and are also compressed in the stacking direction.
Patent Document 3 discloses an auxiliary heater for motor vehicles including an open housing accommodating a layered structure which includes at least one radiator element and at least one heat-emitting element with at least one PTC heating element, and further accommodating at least one spring element pretensioning the layered structure, a plurality of contacts being held in said housing in an insulating manner and electrically connected to the at least one PTC heating element.
Patent Document 4 discloses an insertion-coupled type-connecting terminal, an elastic piece part provided at the tip of a slender board part of a male terminal. When the male terminal is inserted into a female terminal, with a structure such that a contacting projection of the elastic piece part of the male terminal is locally contacted for electrical connection with a ceiling surface of a terminal storing part of the female terminal, a tin-plate thickness applied to the female terminal side is made smaller than that applied to the male terminal side after an area of an electrical contacting surface of the female terminal side at the movement of terminal insertion-coupling is made wider than that of an electrical contact surface of the male terminal side.
Patent Document 5 discloses an electric heater, particularly as an auxiliary heating means for automotive vehicles, comprising a housing which is made open on the elongate housing faces, and a layered structure consisting of at least one PTC heating element, a radiator element, contact sheets for power supply and a resilient element, the layered structure being kept clamped in the housing by the resilient element, wherein an opening is provided laterally in the housing for inserting the resilient element.
Patent Document 6 discloses an electric heating device comprising a housing having a housing lower part that forms a retainer for a heating block and a frame surrounding the retainer, and a housing upper part that is attached to the housing lower part for inclusion of the heating block and includes guiding pins.

CITATION LIST

PATENT DOCUMENT

PATENT DOCUMENT 1: Japanese Patent No. 4880648
PATENT DOCUMENT 2: Japanese Patent No. 4939490
PATENT DOCUMENT 3 : European Patent Application No. 1564503
PATENT DOCUMENT 4 : Japanese Patent Application No 2002124332
PATENT DOCUMENT 5 : European Patent Application No. 1432287
PATENT DOCUMENT 6 : European Patent Application No. 2017547

SOLUTION TO THE PROBLEM

To achieve the above-described object, in the present invention, before assembling a first frame-forming member and a second frame-forming member that constitute a holding frame, a spring member is kept from applying force in the stacking direction to a heating body and a fin.
A first aspect of the present invention is directed to an electric heater in an air conditioner for a vehicle. The electric heater includes: a heating body configured to generate heat when being supplied with electric power; a fin arranged in a manner stacked on the heating body; a one-side spring member arranged on one side of the electric heater in a stacking direction of the heating body and the fin, and configured to apply compression force in the stacking direction to the heating body and the fin; and a holding frame configured to accommodate and hold the heating body, the fin, and the one-side spring member in a stacked manner. Air to be air-conditioned blown into the holding frame is heated when passing through the fin. The holding frame includes a first frame-forming member disposed on one side of the holding frame in a flow direction of the air to be air-conditioned and a second frame-forming member disposed on the other side thereof in combination. The first frame-forming member has: first and second holding walls that are disposed on the one side and the other side, respectively, in the stacking direction of the heating body and the fin; and a one-side connecting portion extending from the first holding wall to the second holding wall and configured to hold the one-side spring member, the heating body, and the fin from the one side in the flow direction of the air to be air-conditioned. A distance between the first holding wall and the second holding wall is set equal to or larger than a total dimension, in the stacking direction, of the heating body, the fin, and the one-side spring member that are stacked without external force in the stacking direction being applied thereto. The second frame-forming member has: a first coupling portion to be coupled to the first holding wall; a second coupling portion to be coupled to the second holding wall; an other-side connecting portion extending from the first coupling portion to the second coupling portion and configured to hold the one-side spring member, the heating body, and the fin from the other side in the flow direction of the air to be air-conditioned; and a one-side spring compression portion configured to be inserted between the first holding wall and the one-side spring member to elastically deform the one-side spring member in the stacking direction of the heating body and the fin.
In other words, during manufacturing of the electric heater, between the first holding wall and the second holding wall of the first frame-forming member, the heating body and the fin are stacked and disposed, and on the one side thereof in the stacking direction, the one-side spring member is disposed. At this time, because the distance between the first holding wall and the second holding wall is kept equal to or larger than the total dimension, in the stacking direction, of the heating body, the fin, and the one-side spring member that are stacked without external force in the stacking direction being applied thereto, the compression force of the spring member does not act on the heating body and the fin. Consequently, even before the second frame-forming member is assembled to the first frame-forming member, the heating body and the fin are less likely to be ejected from the first frame-forming member, and thus assembling workability is improved.
Furthermore, during assembly of the second frame-forming member to the first frame-forming member, when the one-side spring compression portion is inserted between the first holding wall and the one-side spring member, the compression force of the one-side spring member does not act. Thus, force required at the start of the assembly does not have to be great, which also improves the assembling workability.
When the second frame-forming member is assembled to the first frame-forming member, the first coupling portion of the second frame-forming member is coupled to the first holding wall of the first frame-forming member, and the second coupling portion of the second frame-forming member is coupled to the second holding wall of the first frame-forming member. Thus, the heating body, the fin, and the one-side spring member are held by the one-side connecting portion and the one-side connecting portion from both sides in the flow direction of the air to be air-conditioned.
A second aspect of the present invention is an embodiment of the first aspect. In the second aspect, the distance between the first holding wall and the second holding wall is set larger than the total dimension, in the stacking direction, of the heating body, the fin, and the one-side spring member that are stacked without external force in the stacking direction being applied thereto.
By this configuration, the total dimension, in the stacking direction, of the heating body, the fin, and the one-side spring member that are stacked without external force in the stacking direction being applied thereto is smaller than the distance between the first holding wall and the second holding wall. Thus, even if a slight dimensional error in the stacking direction has occurred in the heating body, the fin, and the one-side spring member, compression force of the spring member is not applied to the heating body and the fin before the second frame-forming member is assembled to the first frame-forming member. Consequently, the heating body and the fin are less likely to be ejected from the first frame-forming member, and force required at the start of the assembly does not have to be great.
A third aspect of the present invention is an embodiment of the first aspect. In the third aspect, on a surface of the one-side spring compression portion closer to the one-side spring member, a projection extending in an insertion direction is formed.
By this configuration, during assembly of the second frame-forming member to the first frame-forming member, when the one-side spring compression portion is inserted between the first holding wall and the spring member, the projection of the one-side spring compression portion comes into contact with the one-side spring member. This allows the sliding area between the one-side spring compression portion and the one-side spring member to be reduced, whereby sliding resistance therebetween is reduced.
A fourth aspect of the present invention is an embodiment of the first aspect. In the fourth aspect, the electric heater further includes an other-side spring member arranged on the other side of the electric heater in the stacking direction of the heating body and the fin, and configured to apply compression force in the stacking direction to the heating body and the fin. The distance between the first holding wall and the second holding wall is set equal to or larger than a total dimension, in the stacking direction, of the heating body, the fin, the one-side spring member, and the other-side spring member that are stacked without external force in the stacking direction being applied thereto. The second frame-forming member has an other-side spring compression portion configured to be inserted between the second holding wall and the other-side spring member to elastically deform the other-side spring member in the stacking direction of the heating body and the fin.
By this configuration, during assembly of the second frame-forming member to the first frame-forming member, when the other-side spring compression portion is inserted between the first holding wall and the other-side spring member, force required at the start of the assembly does not have to be great, which also improves the assembling workability. When the second frame-forming member is assembled to the first frame-forming member, the heating body and the fin are compressed by the one-side spring member and the other-side spring member from both sides in the stacking direction.
A fifth aspect of the present invention is directed to a method for manufacturing an electric heater in an air conditioner for a vehicle. The electric heater includes: a heating body configured to generate heat when being supplied with electric power; a fin arranged in a manner stacked on the heating body; a one-side spring member arranged on one side of the electric heater in a stacking direction of the heating body and the fin, and configured to apply compression force in the stacking direction to the heating body and the fin; and a holding frame configured to accommodate and hold the heating body, the fin, and the one-side spring member in a stacked manner. Air to be air-conditioned blown into the holding frame is heated when passing through the fin. The method includes: stacking the heating body and the fin between a first holding wall and a second holding wall of a first frame-forming member included in the holding frame, and also disposing the one-side spring member near the first holding wall between the first holding wall and the second holding wall without applying external force thereto in the stacking direction; subsequently coupling a first coupling portion of a second frame-forming member included in the holding frame to the first holding wall, coupling a second coupling portion of the second frame-forming member to the second holding wall, inserting a one-side spring compression portion of the second frame-forming member between the first holding wall and the one-side spring member to elastically deform the one-side spring member in the stacking direction of the heating body and the fin; and holding, by a one-side connecting portion connecting between the first holding wall and the second holding wall of the first frame-forming member and an other-side connecting portion connecting between the first coupling portion and the second coupling portion of the second frame-forming member, the heating body, the fin, and the one-side spring member from both sides in a flow direction of the air to be air-conditioned.
By this configuration, between the first holding wall and the second holding wall of the first frame-forming member, the heating body and the fin are stacked and disposed, and on the one side thereof in the stacking direction, the one-side spring member is disposed, in which compression force of the spring member is not applied to the heating body and the fin. Consequently, even before the second frame-forming member is assembled to the first frame-forming member, the heating body and the fin are less likely to be ejected from the first frame-forming member, and thus assembling workability is improved.
When the one-side spring compression portion is inserted between the first holding wall and the one-side spring member, compression force of the one-side spring member does not act. Thus, force required at the start of assembly does not have to be great, which also improves the assembling workability.

ADVANTAGES OF THE INVENTION

According to the first and fifth aspects, before assembling the first frame-forming member and the second frame-forming member that constitute the holding frame, the one-side spring member assembled to the first frame-forming member is kept from applying force in the stacking direction to the heating body and the fin. Thus, the heating body and the fin are less likely to be ejected from the first frame-forming member, and force required at the start of the assembly does not have to be great. Consequently, assembling workability can be improved.
According to the second aspect, the distance between the first holding wall and the second holding wall is set larger than the total dimension of the heating body, the fin, and the one-side spring member in the stacking direction. Thus, even if a slight dimensional error in the stacking direction has occurred in the heating body or the fin, for example, the assembling workability can be improved.
According to the third aspect, on the surface of the one-side spring compression portion of the second frame-forming member closer to the one-side spring member, the projection extending in the insertion direction is formed. Thus, during assembly of the second frame-forming member to the first frame-forming member, when the one-side spring compression portion is inserted between the first holding wall and the spring member, sliding resistance between the one-side spring compression portion and the one-side spring member can be reduced. Consequently, the assembling workability can be further improved.
According to the fourth aspect, the heating body and the fin can be compressed by the one-side spring member and the other-side spring member from both sides in the stacking direction, and in this case, the assembling workability can be improved.

BRIEF DESCRIPTION OF THE DRAWINGS

[FIG. 1] FIG. 1 is a perspective view of an electric heater in an air conditioner for a vehicle according to a first embodiment when viewed from an upstream side in the flow direction of air to be air-conditioned.
[FIG. 2] FIG. 2 is a perspective view of the electric heater from which an upstream frame-forming member and left and right cap members are removed.
[FIG. 3] FIG. 3 is a perspective view illustrating an upper portion of the electric heater and its vicinity in FIG. 2 in an enlarged manner.
[FIG. 4] FIG. 4 is a sectional view taken along line IV-IV in FIG. 2.
[FIG. 5] FIG. 5 is a sectional view taken along line V-V in FIG. 1.
[FIG. 6] FIG. 6 is a diagram corresponding to FIG. 2 according to a second embodiment.

DESCRIPTION OF EMBODIMENTS

Embodiments of the present invention will now be described in detail with reference to the drawings. It should be noted that the following description of the preferred embodiments is merely illustrative in nature, and is not intended to limit the scope, applications, or use of the present invention.

(First Embodiment)

FIG. 1 is a diagram illustrating an electric heater 1 in an air conditioner for a vehicle according to a first embodiment of the present invention. This electric heater 1 is a heater arranged inside the air conditioner for a vehicle (not depicted) and configured to heat air to be air-conditioned introduced from outside of a vehicle cabin or inside of the vehicle cabin into the air conditioner for a vehicle. Herein, the air conditioner for a vehicle is installed inside an instrument panel (not depicted) in a vehicle cabin of an automobile, for example, so as to be able to adjust the temperature of air to be air-conditioned to supply the air to various areas in the vehicle cabin. Specifically, although not depicted, the air conditioner for a vehicle includes a casing, a blower fan, a cooling heat exchanger, and the electric heater. The blower fan and the cooling heat exchanger are accommodated in the casing. The blower fan is a component configured to send air to be air-conditioned. The cooling heat exchanger is a component configured to cool the air to be air-conditioned. The electric heater 1 is a component disposed in an area in the casing downstream of the cooling heat exchanger in the flow direction of air to be air-conditioned, and configured to heat the air to be air-conditioned. In the casing, an air mix damper is arranged. The air mix damper is a component configured to change the amount of air passing through the electric heater 1 thereby changing the temperature of air-conditioned air. Furthermore, in the casing, airflow mode dampers including a defroster-mode damper, a ventilation-mode damper, and a heat-mode damper are arranged. The defroster damper is a component configured to change the amount of air-conditioned air to be blown toward an inner surface of a windshield (not depicted), the vent damper is a component configured to change the amount of air-conditioned air to be blown toward the upper body of a passenger, and the heat damper is a component configured to change the amount of air-conditioned air to be blown toward the vicinity of feet of the passenger. Herein, the structure of the air conditioner for a vehicle is not limited to the above-described structure.
The electric heater 1 includes an upper heating body 50, a central first heating body 51, a central second heating body 52, a lower heating body 53, a plurality of fins 54, an upper spring member (one-side spring member) 55, and a holding frame 60, and has a rectangular shape that is laterally long as a whole when viewed from the flow direction of air to be air-conditioned. The upper heating body 50, the central first heating body 51, the central second heating body 52, and the lower heating body 53 have the same structure including a plurality of PTC elements (not depicted) configured to generate heat when being supplied with electric power from a battery (not depicted), for example, mounted on the vehicle, and having a plate-like shape that is laterally long. In each of the upper heating body 50, the central first heating body 51, the central second heating body 52, and the lower heating body 53, the PTC elements are disposed so as to be laterally aligned.
In the description of the present embodiment, the upstream side and the downstream side in the flow direction of air to be air-conditioned are defined as depicted in FIG. 4. However, the air to be air-conditioned may be allowed to flow in the direction opposite to that of this definition. The left side and the right side of the electric heater 1 are defined as depicted in the respective drawings, and may correspond to the left side and the right side of the vehicle, but do not have to correspond thereto. The upper side and the lower side of the electric heater 1 are defined as depicted in the respective drawings, and may correspond to the upper side and the lower side of the vehicle, but do not have to correspond thereto.
As depicted also in FIG. 2, the upper heating body 50 is disposed in an upper portion of the electric heater 1. On the right end of the upper heating body 50, electrode plates 50a to be connected to the corresponding PTC elements are provided so as to protrude rightward. The central first heating body 51 is disposed in a vertically central portion of the electric heater 1 closer to the upper side thereof. On the right end of the central first heating body 51, electrode plates 51a to be connected to the corresponding PTC elements are provided so as to protrude rightward. The central second heating body 52 is disposed in a vertically central portion of the electric heater 1 closer to the lower side thereof. On the right end of the central second heating body 52, electrode plates 52a to be connected to the corresponding PTC elements are provided so as to protrude rightward. The lower heating body 53 is disposed in a lower portion of the electric heater 1. On the right end of the lower heating body 53, electrode plates 53a to be connected to the corresponding PTC elements are provided so as to protrude rightward.
The left ends of the upper heating body 50, the central first heating body 51, the central second heating body 52, and the lower heating body 53 protrude more leftward than the left ends of the fins 54. The right ends of the upper heating body 50, the central first heating body 51, the central second heating body 52, and the lower heating body 53 protrude more rightward than the left ends of the fins 54.
Each fin 54 is a corrugated fin that is continuous and long laterally. The member forming the fin 54 is a thin sheet made of aluminium alloy, for example. The fins 54 are each arranged on upper and lower surfaces of the upper heating body 50, upper and lower surfaces of the central first heating body 51, upper and lower surfaces of the central second heating body 52, and upper and lower surfaces of the lower heating body 53. In other words, the fins 54 are stacked with the upper heating body 50, the central first heating body 51, the central second heating body 52, and the lower heating body 53. Because the fins 54 are in contact with the upper heating body 50, the central first heating body 51, the central second heating body 52, and the lower heating body 53, heats of the upper heating body 50, the central first heating body 51, the central second heating body 52, and the lower heating body 53 are efficiently transmitted to the fins 54.
As depicted in FIG. 3, for example, because the fins 54 are corrugated fins, on upper and lower portions of each fin 54, many crests 54a are formed so as to be laterally spaced apart from each other. A portion between each crest 54a of the upper portion of the fin 54 and the corresponding crest 54a of the lower portion thereof has a flat shape extending substantially in the vertical direction.
As depicted in FIG. 2, between two fins 54 and 54 arranged between the upper heating body 50 and the central first heating body 51, an upper insulating plate 56 extending laterally is arranged. These respective fins 54 are in contact with upper and lower surfaces of the upper insulating plate 56. Between two fins 54 and 54 arranged between the central first heating body 51 and the central second heating body 52, an intermediate insulating plate 57 extending laterally is arranged. These respective fins 54 are in contact with upper and lower surfaces of the intermediate insulating plate 57. Between two fins 54 and 54 arranged between the central second heating body 52 and the lower heating body 53, a lower insulating plate 58 extending laterally is arranged. These respective fins 54 are in contact with upper and lower surfaces of the lower insulating plate 58.
The upper insulating plate 56, the intermediate insulating plate 57, and the lower insulating plate 58 are members each formed of resin or other material having electrical insulating properties, for example, and configured to keep the vertically aligned fins 54 and 54 from being electrically connected to each other. The thickness (vertical dimension) of the upper insulating plate 56, the intermediate insulating plate 57, and the lower insulating plate 58 is set smaller than the thickness of the upper heating body 50, the central first heating body 51, the central second heating body 52, and the lower heating body 53. The left ends of the upper insulating plate 56, the intermediate insulating plate 57, and the lower insulating plate 58 protrude more leftward than the left ends of the fins 54. The left ends of the upper insulating plate 56, the intermediate insulating plate 57, and the lower insulating plate 58 protrude more rightward than the left ends of the fins 54.
The upper spring member 55 is arranged so as to be adjacent to the upper portion of the fin 54 positioned at the upper end of the electric heater 1, that is, on one side of the electric heater in the stacking direction of the heating bodies 50 to 53 and the fins 54. The upper spring member 55 is a component configured to apply biasing force so as to compress, in the stacking direction, the heating bodies 50 to 53, the insulating plate 56 to 58, and the fins 54 held by the holding frame 60, and the whole thereof is formed of a metal material the whole of which is elastic. As depicted in FIG. 4, for example, the upper spring member 55 has: a base-plate portion 55a extending laterally along the upper portion of the fin 54; an upstream elastically deformable portion 55b extending from a peripheral portion of the base-plate portion 55a on its upstream side in the flow direction of air to be air-conditioned; and a downstream elastically deformable portion 55c extending from a peripheral portion of the base-plate portion 55a on its downstream side in the flow direction of air to be air-conditioned.
The upstream elastically deformable portion 55b extends upward from the base-plate portion 55a and extends obliquely toward the downstream side in the flow direction of air to be air-conditioned, and then the tip portion thereof is bent to extend downward. The downstream elastically deformable portion 55c extends from the base-plate portion 55a and extends obliquely toward the upstream side in the flow direction of air to be air-conditioned, and then the tip portion thereof is bent to extend downward. The upstream elastically deformable portion 55b and the downstream elastically deformable portion 55c are configured to elastically deform downward.
As depicted in FIG. 5, the holding frame 60 is a component configured to accommodate and hold the upper heating body 50, the central first heating body 51, the central second heating body 52, the lower heating body 53, the fins 54, the upper spring member 55, the upper insulating plate 56, the intermediate insulating plate 57, and the lower insulating plate 58 in a stacked manner. Most part of a vertically intermediate portion of the holding frame 6 is open, and thus air to be air-conditioned blown into the holding frame 6 is heated when passing through the fins 54.
The holding frame 60 has an upstream frame-forming member (second frame-forming member) 70 disposed on the upstream side (one side) of the holding frame in the flow direction of air to be air-conditioned and a downstream frame-forming member (first frame-forming member) 80 disposed on the downstream side (the other side) thereof in the flow direction of air to be air-conditioned, and includes the upstream frame-forming member 70 and the downstream frame-forming member 80 in combination. The upstream frame-forming member 70 and the downstream frame-forming member 80 are each made by injection-molding resin material having electrical insulating properties. Herein, the flow direction of air to be air-conditioned may be a direction opposite to the direction depicted in FIG. 4. In this case, the frame-forming member 70 is disposed on the downstream side in the flow direction of air to be air-conditioned, and the frame-forming member 80 is disposed on the upstream side in the flow direction of air to be air-conditioned.
The downstream frame-forming member 80 has a downstream upper-peripheral portion 81 disposed on one side (upper side) of the downstream frame-forming member in the stacking direction of the heating bodies 50 to 53 and the fins 54, a downstream lower-peripheral portion 82 disposed on the other side (lower side) thereof in the stacking direction of the heating bodies 50 to 53 and the fins 54, and a downstream connecting portion 83. The downstream upper-peripheral portion 81 extends laterally. On a surface of the downstream upper-peripheral portion 81 on its upstream side in the flow direction of air to be air-conditioned, a plurality of upper holding walls (first holding walls) 81a protruding upstream and extending laterally are formed. The upper holding walls 81a are walls disposed in a manner laterally spaced apart from each other but may be a laterally continuous wall.
On the downstream lower-peripheral portion 82, a lower holding wall (second holding wall) 82a protruding upstream in the flow direction of air to be air-conditioned and extending laterally is formed. In the lower holding wall 82a, fitting holes 82b that are open to the upstream side in the flow direction of air to be air-conditioned and are laterally long are formed.
As depicted in FIG. 4, between the upper holding wall 81a and the lower holding wall 82a of the downstream frame-forming member 80, the heating bodies 50 to 53, the fins 54, the upper spring member 55, and the insulating plates 56 to 58 are disposed. The heating bodies 50 to 53, the fins 54, and the insulating plates 56 to 58 are stacked in the order described above. The upper spring member 55 is disposed between the fin 54 positioned uppermost and the downstream upper-peripheral portion 81. The distance between the upper holding wall 81a and the lower holding wall 82a of the downstream frame-forming member 80 is set equal to or larger than the total dimension, in the stacking direction, of the heating bodies 50 to 53, the fins 54, the insulating plates 56 to 58, and the upper spring member 55 that are stacked without external force in the stacking direction being applied thereto. The expression "without external force in the stacking direction being applied thereto" means that the upper spring member 55 is left free and kept from being elastically deformed, and also the heating bodies 50 to 53 and the fins 54 are kept from deforming.
Specifically, the distance between the upper holding wall 81a and the lower holding wall 82a is a distance between the lower surface (inner surface) 81b of the upper holding wall 81a and the upper surface (inner surface) 82c of the lower holding wall 82a. Than the dimension obtained through addition of all the dimensions of the dimension of the heating bodies 50 to 53 in the stacking direction (thickness direction), the dimension of the fins 54 in the stacking direction (height), the dimension of the upper spring member 55 in the stacking direction (thickness direction), and the dimension of the insulating plates 56 to 58 in the stacking direction (thickness direction), the distance between the lower surface 81b of the upper holding wall 81a and the upper surface 82c of the lower holding wall 82a is smaller by a dimension S.
The dimension S may be zero, and only needs to be such a dimension that allows compression force to be kept from acting on the heating bodies 50 to 53, the fins 54, the upper spring member 55, and the insulating plates 56 to 58 in a state in which these members are disposed between the upper holding wall 81a and the lower holding wall 82a. Because manufacturing tolerances are set for the heating bodies 50 to 53, the fins 54, the upper spring member 55, and the insulating plates 56 to 58, the dimension S is preferably set to several millimeters or larger, for example, in consideration of these tolerances. By this setting, even if all of the heating bodies 50 to 53, the fins 54, the upper spring member 55, and the insulating plates 56 to 58 have positive dimensions within the ranges of the respective tolerances, the compression force of the upper spring member 55 can be kept from acting in a state in which these members are disposed between the upper holding wall 81a and the lower holding wall 82a.
The downstream connecting portion 83 is a portion having a rod-like shape extending from the upper holding wall 81a to the lower holding wall 82a and connecting between the upper holding wall 81a and the lower holding wall 82a while the above-described distance is being maintained. The downstream connecting portion 83 is positioned on the downstream side in the flow direction of air to be air-conditioned, and holds the heating bodies 50 to 53, the fins 54, the upper spring member 55, and the insulating plates 56 to 58 from the downstream side in the flow direction of air to be air-conditioned. The downstream connecting portion 83 is provided in plurality in a manner laterally spaced apart from each other so that air to be air-conditioned can flow through between the downstream connecting portions 83. Each downstream connecting portion 83 may be a vertically extending member, or may be an obliquely extending member.
The upstream frame-forming member 70 has an upstream upper-peripheral portion (first coupling portion) 71 disposed on one side (upper side) of the upstream frame-forming member in the stacking direction of the heating bodies 50 to 53 and the fins 54, an upstream lower-peripheral portion (second coupling portion) 72 disposed on the other side (lower side) thereof in the stacking direction of the heating bodies 50 to 53 and the fins 54, a left connecting portion (other-side connecting portion) 73, a right connecting portion (other-side connecting portion) 74, intermediate connecting portions (other-side connecting portions) 75, and a spring compression portion (one-side spring compression portion) 76. The upstream upper-peripheral portion 71 extends laterally. In the upstream upper-peripheral portion 71, fitting holes 71a that are open to the downstream side in the flow direction of air to be air-conditioned and are laterally long are formed so as to correspond to the upper holding walls 81a of the downstream frame-forming member 80. Into the fitting holes 71a, the upper holding walls 81a of the downstream frame-forming member 80 are inserted to be fitted, whereby the upstream upper-peripheral portion 71 is coupled to the upper holding wall 81a.
On a surface of the upstream lower-peripheral portion 72 on its downstream side in the flow direction of air to be air-conditioned, coupling-plate portions 72a protruding downstream and extending laterally are formed so as to correspond to the fitting holes 82b of the downstream frame-forming member 80. The coupling-plate portions 72a are inserted to be fitted into the fitting holes 82b of the downstream frame-forming member 80, whereby the upstream lower-peripheral portion 72 is coupled to the lower holding wall 82a.
The spring compression portion 76 is positioned on the lower side of the upstream upper-peripheral portion 71 and, as a whole, has a plate-like shape extending laterally. The spring compression portion 76 is a component configured to be inserted into a space between the upper holding walls 81a of the downstream frame-forming member 80 and the upper spring member 55 to elastically deform the upper spring member 55 in the stacking direction of the heating bodies 50 to 53 and the fins 54. The vertical dimension that is a thickness dimension of the spring compression portion 76 is set larger than the dimension S, and is a dimension that enables the upper spring member 55 to be elastically deformed as depicted in FIG. 5 by 1 millimeter or more, for example. Herein, the compression force of the upper spring member 55 can be adjusted depending on the thickness dimension of the spring compression portion 76. Specifically, the compression force of the upper spring member 55 is preferably set to the extent that the heating bodies 50 to 53 and the fins 54, for example, are not displaced.
A portion of the spring compression portion 76 on its downstream side in the flow direction of air to be air-conditioned is a tip portion toward the insertion direction into the above-described space, and thus the thickness of this tip portion of the spring compression portion 76 is set to be smaller at a position closer to the tip. By this setting, the tip portion of the spring compression portion 76 can be easily inserted into the space.
As depicted in FIG. 3, a surface of the spring compression portion 76 closer to the upper spring member 55, that is, a lower surface 76a of the spring compression portion 76 extends laterally. On the lower surface 76a of the spring compression portion 76, a plurality of projections 76b extending in the insertion direction into the space are formed so as to be laterally spaced apart from each other. The projections 76b are continuous on the lower surface 76a of the spring compression portion 76 from the upstream end to the downstream end thereof in the flow direction of air to be air-conditioned. The projections 76b are formed so as to be brought into contact with the upstream elastically deformable portion 55b and the downstream elastically deformable portion 55c of the upper spring member 55. By forming these projections, the sliding area between the spring compression portion 76 and the upper spring member 55 when the spring compression portion is inserted into the above-described space can be reduced, whereby the sliding resistance therebetween can be reduced. Herein, the number of the projections 76b is not limited to a particular number.
As depicted in FIG. 1 and FIG. 2, the left connecting portion 73 has a rod-like shape extending from a left portion of the upstream upper-peripheral portion 71 to a left portion of the upstream lower-peripheral portion 72. The right connecting portion 74 has a rod-like shape extending from a right portion of the upstream upper-peripheral portion 71 to a right portion of the upstream lower-peripheral portion 72. Each intermediate connecting portion 75 has a rod-like shape extending from a laterally intermediate portion of the upstream upper-peripheral portion 71 to a laterally intermediate portion of the upstream lower-peripheral portion 72.
The left connecting portion 73, the right connecting portion 74, and the intermediate connecting portions 75 are portions connecting between the upstream upper-peripheral portion 71 and the upstream lower-peripheral portion 72 while keeping a predetermined distance therebetween. Furthermore, the left connecting portion 73, the right connecting portion 74, and the intermediate connecting portions 75 are positioned on the upstream side in the flow direction of air to be air-conditioned, and holds the heating bodies 50 to 53, the fins 54, the upper spring member 55, and the insulating plates 56 to 58 from the upstream side in the flow direction of air to be air-conditioned. Among the left connecting portion 73, the right connecting portion 74, and the intermediate connecting portions 75, air to be air-conditioned flows through. Herein, the left connecting portion 73, the right connecting portion 74, and the intermediate connecting portions 75 may be portions extending vertically, or may be portions extending obliquely.
As depicted in FIG. 1, on the left end and the right end of the electric heater 1, a left cap member 91 and a right cap member 92 are provided, respectively. The left cap member 91 is formed so as to cover the left ends of the upstream frame-forming member 70 and the downstream frame-forming member 80, and is formed to be fitted onto these left ends. The right cap member 92 is formed so as to cover the right ends of the upstream frame-forming member 70 and the downstream frame-forming member 80, and is formed to be fitted onto these right ends.

(Method for Manufacturing Electric Heater)

The following describes a procedure of assembling the electric heater 1 configured as described above. To begin with, as depicted in FIG. 4, the upper heating body 50, the central first heating body 51, the central second heating body 52, the lower heating body 53, fins 54, the upper insulating plate 56, the intermediate insulating plate 57, and the lower insulating plate 58 are stacked, and are accommodated in the downstream frame-forming member 80. Specifically, the heating bodies 50 to 53, the fins 54, and the insulating plates 56 to 58 are stacked in the order described above, and are disposed between the upper holding walls 81a and the lower holding wall 82a of the downstream frame-forming member 80. The upper spring member 55 is then disposed between the fin 54 positioned uppermost and the downstream upper-peripheral portion 81.
At this time, the distance between the upper holding walls 81a and the lower holding wall 82a of the downstream frame-forming member 80 is kept equal to or larger than the total dimension, in the stacking direction, of the heating bodies 50 to 53, the fins 54, the insulating plates 56 to 58, and the upper spring member 55, and thus compression force of the upper spring member 55 does not act on the heating bodies 50 to 53 and the fins 54. Consequently, even before the upstream frame-forming member 70 is assembled to the downstream frame-forming member 80, the heating bodies 50 to 53 and the fins 54 are less likely to be ejected from the downstream frame-forming member 80, and thus assembling workability is improved.
Furthermore, during assembly of the upstream frame-forming member 70 to the downstream frame-forming member 80, when the spring compression portion 76 is inserted between the upper holding walls 81a and the upper spring member 55, the compression force of the upper spring member 55 does not act. Thus, force required at the start of the assembly does not have to be great, which also improves the assembling workability.
When the spring compression portion 76 is inserted between the upper holding walls 81a and the upper spring member 55, the upper spring member 55 is elastically deformed in the stacking direction of the heating bodies 50 to 53 and the fins 54, whereby the heating bodies 50 to 53, the fins 54, and the insulating plates 56 to 58 are compressed in the stacking direction. Thus, backlash between the heating bodies 50 to 53, the fins 54, and the insulating plates 56 to 58 is substantially eliminated.
When the upstream frame-forming member 70 is assembled to the downstream frame-forming member 80, the upper holding walls 81a of the downstream frame-forming member 80 are inserted to be fitted into the fitting holes 71a of the upstream frame-forming member 70, whereby the upstream upper-peripheral portion 71 is coupled to the upper holding wall 81a. The coupling-plate portions 72a of the upstream frame-forming member 70 on its lower side are inserted to be fitted into the fitting holes 82b of the downstream frame-forming member 80, whereby the upstream lower-peripheral portion 72 is coupled to the lower holding wall 82a. By this assembling, the heating bodies 50 to 53, the fins 54, the insulating plates 56 to 58, and the upper spring member 55 are held by the left connecting portion 73, the right connecting portion 74, the intermediate connecting portions 75, and the downstream connecting portions 83 from both sides in the flow direction of air to be air-conditioned. Finally, the left cap member 91 and the right cap member 92 are assembled to the holding frame 60.

(Effects of Embodiment)

As described in the foregoing, according to the present embodiment, before assembling the upstream frame-forming member 70 and the downstream frame-forming member 80 that constitute the holding frame 60, the upper spring member 55 assembled to the downstream frame-forming member 80 can be kept from applying force in the stacking direction to the heating bodies 50 to 53, the fins 54, and the insulating plates 56 to 58. Thus, the heating bodies 50 to 53, the fins 54, and the insulating plates 56 to 58 are less likely to be ejected from the downstream frame-forming member 80, and force required at the start of the assembly does not have to be great. Consequently, assembling workability can be improved.
The distance between the upper holding walls 81a and the lower holding wall 82a of the downstream frame-forming member 80 is set larger than the total dimension, in the stacking direction, of the heating bodies 50 to 53, the fins 54, the insulating plates 56 to 58, and the upper spring member 55. Thus, even if a slight dimensional error in the stacking direction has occurred in the heating bodies 50 to 53 or the fins 54, for example, the assembling workability can be improved.
On the spring compression portion 76 of the upstream frame-forming member 70, the projections 76b extending in the insertion direction are formed. Thus, when the spring compression portion 76 is inserted between the upper holding walls 81a and the upper spring member 55, sliding resistance between the spring compression portion 76 and the upper spring member 55 can be reduced. Consequently, the assembling workability can be further improved.

(Second Embodiment)

FIG. 6 is a diagram illustrating an electric heater 1 according to a second embodiment of the present invention and corresponding to FIG. 2. The second embodiment is different from the first embodiment in number and arrangement of heating bodies, fins, insulating plates, and spring members, and in structure of a holding frame, and is the same as the first embodiment except these. Thus, hereinafter, components that are the same as those in the first embodiment are designated by the same reference characters, description thereof is omitted, and different components will be described in detail.
In the second embodiment, six heating bodies 101 to 106 are provided, and four insulating plates 107 to 110 are provided. In addition to the upper spring member 55, a lower spring member (other-side spring member) 111 is provided. The lower spring member 111 is a component having a structure similar to that of the upper spring member 55 and configured to apply biasing force so as to compress, in the stacking direction, the heating bodies 101 to 106, the insulating plates 107 to 110, and the fins 54 held by the holding frame 60.
On the downstream lower-peripheral portion 82 of the downstream frame-forming member 80, a plurality of lower holding walls (second holding walls) 82d are formed. The lower holding walls 82d are walls disposed in a manner laterally spaced apart from each other, but may be a laterally continuous wall.
In the upstream lower-peripheral portion 72 of the upstream frame-forming member 70, fitting holes (not depicted) that are open to the downstream side in the flow direction of air to be air-conditioned and are laterally long are formed so as to correspond to the lower holding walls 82d of the downstream frame-forming member 80. Into the fitting holes, the lower holding walls 82d of the downstream frame-forming member 80 are inserted to be fitted, whereby the upstream lower-peripheral portion 72 is coupled to the lower holding wall 82d.
In the second embodiment, the distance between each upper holding wall 81a of the downstream frame-forming member 80 and the corresponding lower holding wall 82d of the downstream frame-forming member 80 is kept equal to or larger than the total dimension, in the stacking direction, of the heating bodies 101 to 106, the fins 54, the insulating plates 107 to 110, the upper spring member 55, and the lower spring member 111.
The upstream frame-forming member 70 has a spring compression portion (other-side spring compression portion) 77 that is inserted between the lower holding walls 82d and the lower spring member 111 to elastically deform the lower spring member 111 in the stacking direction of the heating bodies 101 to 106 and the fins 54. The spring compression portion 77 is positioned on the upper side of the upstream lower-peripheral portion 72 and, as a whole, has a plate-like shape extending laterally, and thus is configured similarly to the spring compression portion 76 on the upper side.
According to the second embodiment, the heating bodies 101 to 106, the insulating plates 107 to 110, and the fins 54 can be compressed by the upper spring member 55 and the lower spring member 111.
The above-described embodiments are merely examples in every respect, and the present invention should not be construed as limited to these embodiments. Furthermore, modifications and changes belonging to the scope equivalent to the claims are all within the scope of the present invention.

INDUSTRIAL APPLICABILITY

As described in the foregoing, the present invention can be applied to an air conditioner installed in an automobile, for example.

DESCRIPTION OF REFERENCE CHARACTERS

1: Electric Heater
50 to 53, 101 to 106: Heating Body
54: Fin
55: Upper Spring Member (One-Side Spring Member)
60: Holding Frame
70: Upstream Frame-Forming Member (Second Frame-Forming Member)
71: Upstream Upper-Peripheral Portion (First Coupling Portion)
72: Upstream Lower-Peripheral Portion (Second Coupling Portion)
73: Left Connecting Portion (Other-Side Connecting Portion)
74: Right Connecting Portion (Other-Side Connecting Portion)
75: Intermediate Connecting Portion (Other-Side Connecting Portion)
76: Spring Compression Portion (One-Side Spring Compression Portion)
77: Spring Compression Portion (Other-Side Spring Compression Portion)
80: Downstream Frame-Forming Member (First Frame-Forming Member)
83: Connecting Portion (One-Side Connecting Portion)
81a: Upper Holding Wall (First Holding Wall)
82a: Lower Holding Wall (Second Holding Wall)
111: Lower Spring Member (Other-Side Spring Member)

Claims

An electric heater (1) in an air conditioner for a vehicle, the electric heater (1) comprising:
a heating body (50 to 53, 101 to 106) configured to generate heat when being supplied with electric power;

a fin (54) arranged in a manner stacked on the heating body (50 to 53, 101 to 106);

a one-side spring member (55) arranged on one side of the electric heater (1) in a stacking direction of the heating body (50 to 53, 101 to 106) and the fin (54), and configured to apply compression force in the stacking direction to the heating body (50 to 53, 101 to 106) and the fin (54); and

a holding frame (60) configured to accommodate and hold the heating body (50 to 53, 101 to 106), the fin (54), and the one-side spring member (55) in a stacked manner, wherein

air to be air-conditioned blown into the holding frame (60) is heated when passing through the fin (54),

the holding frame (60) includes a first frame-forming member (80) disposed on one side of the holding frame (60) in a flow direction of the air to be air-conditioned and a second frame-forming member (70) disposed on the other side thereof in combination,

the first frame-forming member (80) has: first (81a) and second holding walls (82a) that are disposed on the one side and the other side, respectively, in the stacking direction of the heating body (50 to 53, 101 to 106) and the fin (54); and a one-side connecting portion (83) extending from the first holding wall (81a) to the second holding wall (82a) and configured to hold the one-side spring member (55), the heating body (50 to 53, 101 to 106), and the fin (54) from the one side in the flow direction of the air to be air-conditioned,

a distance between the first holding wall (81a) and the second holding wall (82a) is set equal to or larger than a total dimension, in the stacking direction, of the heating body (50 to 53, 101 to 106), the fin (54), and the one-side spring member (55) that are stacked without external force in the stacking direction being applied thereto,

the second frame-forming member (70) has: a first coupling portion (71) to be coupled to the first holding wall (81a); a second coupling portion (72) to be coupled to the second holding wall (82a); an other-side connecting portion (73, 74, 75) extending from the first coupling portion (71) to the second coupling portion (72) and configured to hold the one-side spring member (55), the heating body (50 to 53, 101 to 106), and the fin (54) from the other side in the flow direction of the air to be air-conditioned; and a one-side spring compression portion (76) configured to be inserted between the first holding wall (81a) and the one-side spring member (55) to elastically deform the one-side spring member (55) in the stacking direction of the heating body (50 to 53, 101 to 106) and the fin (54),

characterized in that the one-side spring member (55) is adjacent to the upper portion of the fin (54) positioned at the upper end of the electric heater (1), that is, on one side of the electric heater in the stacking direction of the heating body (50 to 53,101 to 106) and the fin (54),

the one-side spring member (55) further has: a flat base-plate portion (55a) extending laterally along the upper portion of

the fin (54); an upstream elastically deformable portion (55b) extending from a peripheral portion of the base-plate portion (55a) on its upstream side in the flow direction of the air to be air-conditioned; and a downstream elastically deformable portion (55c) extending from a peripheral portion of the base-plate portion (55a) on its downstream side in the flow direction of the air to be air-conditioned,

the upstream elastically deformable portion (55b) extends away from the base-plate portion (55a) and extends obliquely toward the downstream side in the flow direction of the air to be air-conditioned, and then a tip portion thereof is bent to extend to come near the base-plate portion,

the downstream elastically deformable portion (55c) extends away from the base-plate portion (55a) and extends obliquely toward the upstream side in the flow direction of the air to be air-conditioned, and then a tip portion thereof is bent to extend to come near the base-plate portion (55a), and

on a surface of the one-side spring compression portion (76) closer to the one-side spring member (55), a projection extending in an insertion direction is formed.
The electric heater (1) of claim 1, wherein
the distance between the first holding wall (81a) and the second holding wall (82a) is set larger than the total dimension, in the stacking direction, of the heating body (50 to 53, 101 to 106), the fin (54), and the one-side spring member (55) that are stacked without external force in the stacking direction being applied thereto.
The electric heater (1) of claim 1, further comprising
an other-side spring member (111) arranged on the other side of the electric heater (1) in the stacking direction of the heating body (50 to 53, 101 to 106) and the fin (54), and configured to apply compression force in the stacking direction to the heating body (50 to 53, 101 to 106) and the fin (54), wherein
the distance between the first holding wall (81a) and the second holding wall (82a) is set equal to or larger than a total dimension, in the stacking direction, of the heating body (50 to 53, 101 to 106), the fin (54), the one-side spring member (55), and the other-side spring member (111) that are stacked without external force in the stacking direction being applied thereto, and
the second frame-forming member (70) has an other-side spring compression portion (77) configured to be inserted between the second holding wall (82a) and the other-side spring member (111) to elastically deform the other-side spring member (111) in the stacking direction of the heating body (50 to 53, 101 to 106) and the fin (54).
A method for manufacturing an electric heater (1) in an air conditioner for a vehicle, the electric heater (1) including:
a heating body (50 to 53, 101 to 106) configured to generate heat when being supplied with electric power;

a fin (54) arranged in a manner stacked on the heating body (50 to 53, 101 to 106);

a one-side spring member (55) arranged on one side of the electric heater (1) in a stacking direction of the heating body (50 to 53, 101 to 106) and the fin (54), and configured to apply compression force in the stacking direction to the heating body (50 to 53, 101 to 106) and the fin (54); and

a holding frame (60) configured to accommodate and hold the heating body (50 to 53, 101 to 106), the fin (54), and the one-side spring member (55) in a stacked manner, air to be air-conditioned blown into the holding frame (60) being heated when passing through the fin (54),

the one-side spring member (55) is adjacent to the upper portion of the fin (54) positioned at the upper end of the electric heater (1), that is, on one side of the electric heater in the stacking direction of the heating body (50 to 53,101 to 106) and the fin (54),

the one-side spring member (55) further has: a flat base-plate portion (55a) extending laterally along the upper portion of the fin (54); an upstream elastically deformable portion (55b) extending from a peripheral portion of the base-plate portion (55a) on its upstream side in the flow direction of the air to be air-conditioned; and a downstream elastically deformable portion (55c) extending from a peripheral portion of the base-plate portion (55a) on its downstream side in the flow direction of the air to be air-conditioned,

the upstream elastically deformable portion (55b) extends away from the base-plate portion (55a) and extends obliquely toward the downstream side in the flow direction of the air to be air-conditioned, and then a tip portion thereof is bent to extend to come near the base-plate portion,

the downstream elastically deformable portion (55c) extends away from the base-plate portion (55a) and extends obliquely toward the upstream side in the flow direction of the air to be air-conditioned, and then a tip portion thereof is bent to extend to come near the base-plate portion (55a), and

on a surface of the one-side spring compression portion (76) closer to the one-side spring member (55), a projection extending in an insertion direction is formed,

the method comprising:
stacking the heating body (50 to 53, 101 to 106) and the fin (54) between a first holding wall (81a) and a second holding wall (82a) of a first frame-forming member (80) included in the holding frame (60), and also disposing the one-side spring member (55) near the first holding wall (81a) between the first holding wall (81a) and the second holding wall (82a) without applying external force thereto in the stacking direction;

subsequently coupling a first coupling portion (71) of a second frame-forming member (70) included in the holding frame (60) to the first holding wall (81a), coupling a second coupling portion (72) of the second frame-forming member (70) to the second holding wall (82a), inserting a one-side spring compression portion (76) of the second frame-forming member (70) between the first holding wall (81a) and the one-side spring member (55) to elastically deform the one-side spring member (55) in the stacking direction of the heating body (50 to 53, 101 to 106) and the fin (54); and

holding, by a one-side connecting portion (83) connecting between the first holding wall (81a) and the second holding wall (82a) of the first frame-forming member (80) and an other-side connecting portion (73, 74, 75) connecting between the first coupling portion (71) and the second coupling portion (72) of the second frame-forming member (70), the heating body (50 to 53, 101 to 106), the fin (54), and the one-side spring member (55) from both sides in a flow direction of the air to be air-conditioned.