JP6568738B2 - Electric heater - Google Patents

Description

  The present invention relates to an electric heater provided with a heating element that generates heat when electric power is supplied.

  For example, an electric heater for heating air for air conditioning may be provided in the vehicle air conditioner. As this type of electric heater, one provided with a heating element composed of a PTC element that generates heat when electric power is supplied is known (for example, see Patent Documents 1 and 2). That is, the electric heaters of Patent Documents 1 and 2 include a plurality of heat generating elements, a heat dissipating element composed of fins arranged between the heat generating elements, and a housing that accommodates the heat generating elements and the heat dissipating elements. After the outside air flows in and is heated from the opening on the upstream side formed in the above, it flows out from the opening on the downstream side.

  Each heating element holds a pair of thin metal strips, a PTC element disposed between the thin metal strips, and a pair of thin metal strips and a PCT element, as described in FIG. 7 of each document. It consists of an arrangement frame. The arrangement frame has a holding projection that engages with one thin metal strip from the outer surface and a holding projection that engages with the other thin metal strip from the outer surface, and the one thin metal strip and the other thin plate. A part of the arrangement frame is interposed between the metal strip.

  Also, a spring element for pressing the heat generating element and the heat radiating element in the stacking direction is disposed inside the housing, and a compressive force acts on the heat generating element and the heat radiating element by the spring element. Yes.

Japanese Patent No. 4880648 Japanese Patent No. 4939490

  By the way, in Patent Documents 1 and 2, one holding projection of the heat generating element arrangement frame is engaged with the outer surface of one thin metal strip, and the other holding projection is engaged with the outer surface of the other thin metal strip. Therefore, both the thin metal strips and the PTC element can be held in a stacked state by the arrangement frame, and there is an advantage that workability when the heat generating element is assembled to the housing can be improved.

  However, since the holding projections are in contact with the thin metal strip in a state where a part of the arrangement frame is interposed between one thin metal strip and the other thin metal strip, one thin metal strip and the other thin metal strip are in contact with each other. The metal band is completely restrained by the arrangement frame, and the distance between the two thin metal bands cannot be changed.

  Here, the compressive force of the spring element acts in the direction of reducing the distance between the two thin metal strips with respect to the outer surface of one thin metal strip and the other thin metal strip. When the sheet metal strip and the other sheet metal strip are completely restrained by the arrangement frame, even if a compression force is applied by the spring element, the distance between the two sheet metal strips hardly changes.

  However, since it is inevitable that variations in thickness and shape occur within the range of manufacturing tolerances for thin metal strips, PTC elements, etc., a patent in which the distance between both thin metal strips cannot be reduced by the compression force of the spring element In Documents 1 and 2, it is considered that the pressure contact between the thin metal strip and the PTC element is insufficient, and as a result, the amount of heat generated by the PTC element may be reduced.

  The present invention has been made in view of such points, and the object of the present invention is to improve the assembly workability by holding the heat generating element and the conductive member in a holder and integrating them. An object of the present invention is to secure a sufficient pressure contact force between the conductive member and the heating element to suppress a decrease in the amount of heat generated by the heating element.

  In order to achieve the above object, in the present invention, the first conductive member and the second conductive member are held in the holder by the engaging portion of the holder, and in this state, the first conductive member is held in the second conductive member. Displaceable in the direction of approaching and leaving.

The first invention is
A heat generating part having a heat generating element that generates heat by supplying power;
Fins for transferring heat of the heat generating part to external air;
A housing for holding the heat generating portion and the fin in a state in which the heat generating portion and the fin are stacked in a direction intersecting with the flow direction of the external air;
An electric heater that is assembled to the housing and includes a spring member for applying a compressive force in the stacking direction to the heat generating portion and the fin.
The heat generating part is arranged so as to sandwich the heat generating element from both sides in the stacking direction and to be in contact with the heat generating element so as to supply electric power to the heat generating element from the outside. A member and a holder for holding the heating element, the first conductive member, and the second conductive member;
The holder includes a first engagement portion that engages with the first conductive member from the side opposite to the heating element side, and a holder that engages with the second conductive member from the side opposite to the heating element side. A second engaging portion to be joined,
The holder is configured to allow displacement of the first conductive member in a direction in which the first conductive member is in contact with or separated from the second conductive member between the first engagement portion and the second engagement portion. It is characterized by.

  According to this configuration, the first conductive member and the second conductive member are held in the holder by the first engaging portion and the second engaging portion of the holder, and in this state, the heating element is connected to the first conductive member and the second conductive member. Since it is disposed between the two conductive members, the heating element is also held by the holder. Therefore, since the heat generating part is integrated, the assembly workability is improved when the heat generating part is assembled to the housing together with the fins.

  After assembly, the compression force by the spring member also acts on the heat generating portion. At this time, since the first conductive member held by the holder can be displaced in the direction of contact with and away from the second conductive member, the first conductive member, the second conductive member, and the heating element Even if the thickness or shape varies, the pressure contact force between the first conductive member and the heating element and the pressure contact force between the second conductive member and the heating element can be sufficiently secured.

According to a second invention, in the first invention,
The holder has a frame shape surrounding the periphery of the first conductive member and the second conductive member,
The first engaging portion and the second engaging portion are formed by protrusions that protrude from the inner surface of the holder toward the inside of the holder.

  According to this configuration, since the first engaging portion and the second engaging portion are protrusions, the first conductive member and the second conductive member are reliably engaged, and the engaged state is maintained. It becomes possible to do.

According to a third invention, in the second invention,
The holder is made of resin material,
When the holder is viewed from the stacking direction, the first engaging portion and the second engaging portion are arranged so as not to overlap each other.

  That is, when the holder is viewed from the stacking direction, the first engagement portion and the second engagement portion are not overlapped with each other, so that when the holder is molded, the first engagement portion and the second engagement portion are undercut. There is no part. Therefore, it is not necessary to provide a slide mold or the like for avoiding the undercut portion in the mold.

According to a fourth invention, in any one of the first to third inventions,
The second conductive member is insert-molded in the holder.

  According to this configuration, the second conductive member and the holder are reliably integrated by insert-molding the second conductive member into the holder. Moreover, the assembly man-hour at the assembly site is reduced.

According to a fifth invention, in any one of the first to third inventions,
The holder is configured to allow displacement of the second conductive member in a direction in which the second conductive member comes into contact with and separates from the first conductive member between the first engagement portion and the second engagement portion. It is characterized by.

  According to this configuration, the second conductive member held by the holder can be displaced in a direction in which the second conductive member is brought into contact with or separated from the first conductive member. Therefore, the pressure contact force between the first conductive member and the heating element. In addition, it is possible to ensure a sufficient pressure contact force between the second conductive member and the heating element.

A sixth invention is the second or third invention, wherein
On the inner surface of the holder, there is provided a protrusion that protrudes inward of the holder from between the first engagement portion and the second engagement portion,
The dimension of the protrusion in the stacking direction is set shorter than the dimension of the heat generating element in the stacking direction.

  According to this configuration, the heating element is positioned by the protruding portion on the inner surface of the holder. And since the dimension of the said lamination direction in this protrusion part is shorter than the dimension of the said lamination direction in a heat generating element, a protrusion part inhibits the displacement to the direction which a 1st conductive member contacts / separates to a 2nd conductive member. Never do.

  According to the first invention, the first conductive member and the second conductive member are held in the holder by the engaging portion of the holder, and in this state, the first conductive member is brought into contact with and separated from the second conductive member. Since the displacement in the direction is made possible, the press working force between the first and second conductive members and the heat generating element is sufficiently secured to suppress the decrease in the heat generation amount of the heat generating element while improving the assembly workability of the heat generating part. be able to.

  According to the second aspect of the invention, since the first engaging portion and the second engaging portion are constituted by the protrusions protruding from the inner surface of the holder, the first conductive member and the second conductive member are prevented from dropping from the holder. It can be prevented in advance.

  According to the third invention, since the first engagement portion and the second engagement portion are arranged so as not to overlap each other when the holder is viewed from the stacking direction, the first engagement portion and the second engagement are arranged. The part does not become an undercut part. Therefore, mold costs can be reduced.

  According to the fourth invention, since the second conductive member is insert-molded in the holder, the second conductive member and the holder can be reliably integrated. Moreover, the assembly man-hour at the assembly site can be reduced.

  According to the fifth aspect, since the second conductive member can be displaced in the direction of contacting and separating from the first conductive member, sufficient pressure contact force between the first and second conductive members and the heating element is ensured. it can.

  According to the sixth aspect, the heating element can be positioned by the protrusion provided on the inner surface of the holder. And since the dimension of the said lamination direction in the protrusion part was set shorter than the dimension of the said lamination direction in a heat generating element, a protrusion part inhibits the displacement to the direction in which a 1st conductive member contacts / separates a 2nd conductive member. The pressure contact force between the first and second conductive members and the heat generating element can be sufficiently secured.

It is the perspective view which looked at the electric heater which concerns on embodiment from the flow direction downstream of external air. FIG. 2 is a view corresponding to FIG. 1 with a left cap and a right cap removed. It is the III-III sectional view taken on the line in FIG. It is a perspective view of the 1st exothermic part. It is a disassembled perspective view of a 1st heat generating part. It is the figure which expanded the part enclosed with the dashed-dotted line in FIG. 4, and was seen from diagonally upward. It is a top view which shows a part of spring member. It is a perspective view which shows the assembly | attachment point of a spring member. It is a perspective view which shows the state in the middle of inserting in the housing of a spring member. FIG. 7 is a sectional view taken along line XX in FIG. 6. FIG. 11 is a diagram corresponding to FIG. 10 according to a modified example.

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

  FIG. 1 is a perspective view of an electric heater 1 according to an embodiment of the present invention. The electric heater 1 is, for example, a so-called PTC heater that is disposed in a vehicle air conditioner (not shown) and is used as an air heater that heats air for air conditioning. The electric heater 1 can be used as an auxiliary air heater, or can be used as a main air heater with a large heating amount. The electric heater 1 is supplied with electric power from a battery (not shown) mounted on the vehicle. In addition, although not shown in figure, the electric heater 1 can be used when heating various air besides the air heater of an air conditioner.

  1 and 2, the case where the electric heater 1 is viewed from the downstream side with reference to the flow direction of the external air is described. However, the electric heater 1 is defined as the downstream side in FIGS. This side may be used as the upstream side. As for the left-right direction of the electric heater 1, the right side when viewed from the downstream side in the flow direction of the external air is referred to as “right”, and the left side is referred to as “left”.

  The electric heater 1 includes first to fourth heat generating portions A1 to A4, fins 2, a housing 3 that holds the first to fourth heat generating portions A1 to A4 and the fins 2, and a spring member 4. The left cap 5 and the right cap 6 have a substantially rectangular shape that is long in the left-right direction as a whole. The first to fourth heat generating portions A1 to A4 are all the same, and have a shape that is long in the left-right direction of the electric heater 1 as shown in FIG. Further, as shown in FIG. 2, the first heat generating part A1 is located at the uppermost position, the fourth heat generating part A4 is located at the lowest position, and the second heat generating part A2 is located below the first heat generating part A1. The third heat generating part A3 is located between the second heat generating part A2 and the fourth heat generating part A4. The fins 2 are disposed on the upper and lower surfaces of the first heat generating part A1, and also on the upper and lower surfaces of the second heat generating part A2, the upper and lower surfaces of the third heat generating part A3, and the upper and lower surfaces of the fourth heat generating part A4. Has been placed. That is, the first to fourth heat generating portions A1 to A4 and the fins 2 are stacked in the vertical direction, which is a direction intersecting the flow direction of the external air.

  The fin 2 is a corrugated fin made of, for example, an aluminum alloy thin plate material, and is a heat transfer member for transmitting the heat of the first to fourth heat generating parts A1 to A4 to the external air. The direction in which the waveform of the fin 2 continues is the left-right direction of the electric heater 1. The fin 2 is continuous from the left end portion to the right end portion of the housing 3 inside the housing 3. External air flows through the fins 2. Moreover, you may make it control to supply electric power separately with respect to 1st-4th heat-generating part A1-A4, and you may make it supply electric power to all.

  As shown in FIG. 5, the first heat generating part A1 includes a plurality of PTC elements 10, 10,..., An upper electrode plate (first conductive member) 12, and a lower electrode plate (second conductive member) 13. And a holder 14. Each PTC element 10 is a heating element that generates heat when power is supplied, and is formed in a plate shape that is long in the left-right direction of the electric heater 1. In this embodiment, the number of PTC elements 10 is four, and the PTC elements 10 are arranged at intervals in the left-right direction. However, the number and arrangement of the PTC elements 10 are not limited to this.

  The upper electrode plate 12 and the lower electrode plate 13 are formed by molding a conductive metal plate, and are electrically connected in contact with each PTC element 10. The upper electrode plate 12 extends in the left-right direction. A through hole 12 a that penetrates in the vertical direction (thickness direction of the upper electrode plate 12) is formed at the right end of the upper electrode plate 12. The left end portion of the upper electrode plate 12 is a connection portion 12b formed so as to extend leftward after being bent upward. A harness (not shown) to which power of a battery mounted on the vehicle is supplied can be connected to the connection portion 12b.

  The lower electrode plate 13 also extends in the left-right direction. A through hole 13 a that penetrates in the vertical direction (thickness direction of the lower electrode plate 13) is formed at the right end of the lower electrode plate 13. The left end portion of the lower electrode plate 13 is a connection portion 13b formed to extend to the left side. As shown in FIG. 4, the connecting portion 13b of the lower electrode plate 13 and the connecting portion 12b of the upper electrode plate 12 are separated from each other in the vertical direction. The connecting portion 13b of the lower electrode plate 13 can also be connected to a harness (not shown).

  As shown in FIGS. 3 and 10, the PTC elements 10, 10,... Are arranged between the upper electrode plate 12 and the lower electrode plate 13. That is, the upper electrode plate 12 and the lower electrode plate 13 sandwich the PTC elements 10, 10,... From both sides in the stacking direction of the first to fourth heating portions A1 to A4 and the fin 2, and the PTC elements 10, Are arranged so as to be in contact with the PTC elements 10, 10... For supplying electric power from the outside.

  The holder 14 is made of a resin material having heat resistance and electrical insulation, and is for holding and integrating the PTC elements 10, 10,..., The upper electrode plate 12 and the lower electrode plate 13. As shown in FIG. 5, the holder 14 has a frame shape surrounding the peripheral portions of the PTC elements 10, 10,..., The upper electrode plate 12 and the lower electrode plate 13. That is, the holder 14 has a downstream side wall portion 20 extending along a downstream edge of the upper electrode plate 12 and the lower electrode plate 13 in the direction of the external air flow, and an external air flow of the upper electrode plate 12 and the lower electrode plate 13. An upstream side wall portion 21 extending along the edge on the upstream side in the direction, a left wall portion 22 extending so as to connect the left end portions of the downstream side wall portion 20 and the upstream side wall portion 21, and the downstream side wall portion 20 and the upstream side wall portion 21. And a right wall portion 23 extending so as to connect the right end portions of each other. The upper part of the left wall part 22 protrudes upward from the upper part of the downstream side wall part 20 and the upstream side wall part 21. The connection portion 12b of the upper electrode plate 12 is fitted to the upper portion of the left wall portion 22 from above. Further, the connecting portion 13b of the lower electrode plate 13 is fitted to the lower portion of the left wall portion 22 from below.

  The upper part of the right wall part 23 of the holder 14 projects upward from the upper parts of the downstream side wall part 20 and the upstream side wall part 21, and the lower part of the right wall part 23 of the holder 14 is the lower part of the downstream side wall part 20 and the upstream side wall part 21. Protrudes downward. Therefore, when the vertical dimension of the downstream side wall part 20, the upstream side wall part 21, the left wall part 22 and the right wall part 23 is compared, the downstream side wall part 20 and the upstream side wall part 21 are the shortest. As shown in FIGS. 3 and 10, the vertical dimension of the downstream side wall part 20 and the upstream side wall part 21 is the vertical dimension of the PTC element 10, the vertical dimension of the upper electrode plate 12, and the lower electrode plate 13. It is set longer than the length including the vertical dimension.

  As shown in FIG. 5, the downstream side wall portion 20 is provided with four flat portions 20a, 20a,. Each flat portion 20a extends in the vertical direction. As shown in FIGS. 3 and 10, the inner surface (the inner surface of the holder 14) of each flat portion 20 a of the downstream side wall portion 20 is engaged with the upper electrode plate 12 from the side opposite to the PTC element 10 side (upper side). Downstream upper engaging portion (first engaging portion) 20b to be joined, and downstream lower engaging portion (first engaging portion) engaged with the lower electrode plate 13 from the opposite side (lower side) to the PTC element 10 side. 2 engaging portion) 20c and a downstream protruding portion 20d protruding inward of the holder 14 from between the downstream upper engaging portion 20b and the downstream lower engaging portion 20c. The downstream upper engagement portion 20b and the downstream lower engagement portion 20c are each formed by a protrusion that protrudes inward of the holder 14.

  The downstream upper engagement portion 20b is formed at a portion on the right side of the flat portion 20a, while the downstream lower engagement portion 20c is formed at a portion on the left side of the flat portion 20a. When the holder 14 is viewed from the stacking direction of the first to fourth heat generating portions A1 to A4 and the fins 2, the downstream upper engaging portion 20b and the downstream lower engaging portion 20c are arranged so as not to overlap each other. ing. Thereby, at the time of shaping | molding of the holder 14, the downstream upper engaging part 20b and the downstream lower engaging part 20c do not become an undercut part. Therefore, it is not necessary to provide the mold with a slide mold or the like for avoiding the undercut portion, so that the mold cost can be reduced.

  The vertical separation between the downstream upper engagement portion 20b and the downstream lower engagement portion 20c is the vertical dimension of the PTC element 10, the vertical dimension of the upper electrode plate 12, and the vertical direction of the lower electrode plate 13. It is set to be longer than the length including the above dimensions. Further, the dimension in the stacking direction (vertical direction) of the downstream protrusion 20 d is set shorter than the dimension in the stacking direction of the PTC element 10.

  Further, as shown in FIG. 5, the upstream side wall portion 21 is also provided with four flat portions 21a, 21a,. Each flat part 21a is arrange | positioned so as to oppose each flat part 20a of the downstream side wall part 20, and is extended in the up-down direction. As shown in FIGS. 3 and 10, the inner surface (the inner surface of the holder 14) of each flat portion 21 a of the upstream side wall portion 21 is engaged with the upper electrode plate 12 from the side opposite to the PTC element 10 side (upper side). An upstream upper engagement portion (first engagement portion) 21b to be joined, and an upstream lower engagement portion (first engagement portion) that engages with the lower electrode plate 13 from the opposite side (lower side) to the PTC element 10 side. (2 engaging portions) 21c and an upstream protruding portion 21d protruding inward of the holder 14 from between the upstream upper engaging portion 21b and the upstream lower engaging portion 21c are provided. The upstream upper engagement portion 21 b and the upstream lower engagement portion 21 c are each configured by a protrusion that protrudes inward of the holder 14.

  The upstream upper engagement portion 21b is formed at the left portion of the flat portion 21a, while the upstream lower engagement portion 21c is formed at the right portion of the flat portion 20a. When the holder 14 is viewed from the stacking direction of the first to fourth heat generating portions A1 to A4 and the fins 2, the upstream upper engaging portion 21b and the upstream lower engaging portion 21c are arranged so as not to overlap each other. ing. Thereby, when the holder 14 is molded, the upstream upper engaging portion 21b and the upstream lower engaging portion 21c do not become undercut portions, so that the mold cost can be reduced.

  The vertical separation between the upstream upper engagement portion 21b and the upstream lower engagement portion 21c is the vertical dimension of the PTC element 10, the vertical dimension of the upper electrode plate 12, and the vertical direction of the lower electrode plate 13. It is set to be longer than the length including the above dimensions. Further, the dimension in the stacking direction (vertical direction) of the upstream protrusion 21d is set to be shorter than the dimension in the stacking direction of the PTC element 10.

  The separation dimension between the downstream upper engagement portion 20b and the downstream lower engagement portion 20c is set as described above, and the separation dimension between the upstream upper engagement portion 21b and the upstream lower engagement portion 21c is as described above. With this setting, the upper electrode plate 12 and the lower electrode plate 13 can be moved in the vertical direction inside the holder 14 together with the PTC element 10. That is, the upper electrode plate 12 is vertically moved between the downstream upper engagement portion 20b and the downstream lower engagement portion 20c and between the upstream upper engagement portion 21b and the upstream lower engagement portion 21c. It can be moved, and this allows the displacement in the direction of contacting and separating from the lower electrode plate 13. Similarly, the lower electrode plate 13 is placed between the downstream upper engagement portion 20b and the downstream lower engagement portion 20c, and between the upstream upper engagement portion 21b and the upstream lower engagement portion 21c. Further, it can be moved in the vertical direction, and this allows the displacement in the direction of contact with and away from the upper electrode plate 12.

  Note that the second to fourth heat generating portions A2 to A4 have the same structure as the first heat generating portion A1, and thus the description thereof is omitted.

  Next, the structure of the housing 3 will be described. As shown in FIGS. 1 to 3, the housing 3 is a combination of an upstream housing component member 30 and a downstream housing component member 31 that are divided in the flow direction of the external air. The upstream housing constituent member 30 and the downstream housing constituent member 31 are made of a resin material having heat resistance and electrical insulation. As shown in FIG. 3, the upstream housing component 30 is formed with an upstream opening 30 a through which external air flows. The downstream housing component 31 also has a downstream opening 31a through which external air flows. The upstream opening 30a and the downstream opening 31a have substantially the same shape and the same size. The downstream opening 31 a of the downstream housing component 31 is an insertion portion for inserting the spring member 4 from the outside to the inside of the housing 3, as will be described in detail later.

  As shown in FIG. 3, the downstream housing component 31 is formed with a fitting convex portion 31b that protrudes toward the upstream side. On the other hand, the upstream housing constituent member 30 is formed with a fitting recess 30b into which the fitting convex portion 31b of the downstream housing constituent member 31 is fitted. In a state where the upstream housing component 30 and the downstream housing component 31 are combined, the fitting convex portion 31b is fitted in a state inserted into the fitting concave portion 30b.

  As shown in FIGS. 1 and 2, the downstream housing component 31 is provided with a plurality of reinforcing portions 31 c extending in the vertical direction so as to cross the downstream opening 31 a in the vertical direction. In this embodiment, the reinforcing portion 31c is formed in a bar shape extending in an inclined manner. However, the present invention is not limited thereto, and for example, it may extend in the vertical direction.

  The upper end portion of the reinforcing portion 31 c is continuous with the lower surface of the upper wall portion of the downstream housing component 31. The lower end portion of the reinforcing portion 31 c is continuous with the upper surface of the lower wall portion of the downstream housing component 31. Further, the upper ends or the lower ends of the two adjacent reinforcing portions 31c are integrated.

  As shown in FIG. 3, the upstream housing component 30 is also provided with a reinforcing portion 30 c similar to the downstream housing component 31.

  As shown in FIG. 3, between the reinforcement part 31c of the downstream housing component 31 and the holder 14 of the first heat generation part A1, and the reinforcement part 30c of the upstream housing component 30 and the first heat generation part A1. A predetermined gap is formed between each of the holders 14. That is, the outer surface of the upstream side wall portion 21 of the holder 14 is separated from the inner surface of the reinforcing portion 30 c of the upstream housing component 30, and the outer surface of the downstream side wall portion 20 of the holder 14 is separated from the downstream housing component 31. It is away from the inner surface of the reinforcing part 31c. Thus, the first to fourth heat generating portions A1 to A4 do not come into strong contact with the reinforcing portions 30c and 31c, and when the compressive force by the spring member 4 is applied inside the housing 3, the first heat generating portion A1 to A4 The first to fourth heat generating portions A1 to A4 can move in the vertical direction.

  Next, the spring member 4 will be described. The spring member 4 is assembled in the housing 3 and applies a compressive force to the first to fourth heat generating portions A1 to A4 and the fins 2 in the stacking direction. The spring member 4 is formed, for example, by molding a metal plate having elasticity, and extends from the left end portion of the housing 3 to the right end portion. As shown in FIGS. 7 to 9, the spring member 4 is bent upward from the plate portion 40 extending in the left-right direction and the upstream edge of the plate portion 40 in the flow direction of the external air, and then extends downstream. A plurality of upstream urging portions 41 and a plurality of downstream urging portions 42 that are bent upward from an edge of the plate portion 40 on the downstream side in the flow direction of the external air and then extend upstream are provided. . The upstream urging portions 41 are provided with a space in the left-right direction, and the downstream urging portions 42 are also provided in the same manner.

  The lower surface of the plate portion 40 of the spring member 4 is in contact with the upper surface of the fin 2 disposed at the upper end portion. The upper end portions of the upstream biasing portion 41 and the downstream biasing portion 42 are in contact with the inner surface of the upper wall portion of the housing 3. Between the fin 2 at the upper end and the inner surface of the upper wall portion of the housing 3, the upstream biasing portion 41 and the downstream biasing portion 42 are mainly elastically deformed, whereby the first to fourth heat generating portions A1 to A1. It is comprised so that a compressive force may be applied with respect to A4 and the fin 2 in the lamination direction.

  As shown in FIG. 7, the plate portion 40 of the spring member 4 has a downstream housing component 31 between the adjacent upstream biasing portions 41 and 41 and between the adjacent downstream biasing portions 42 and 42. A cutout portion 40a into which the reinforcing portion 31c is fitted is formed. The notch 40a is formed so as to extend downstream from the upstream edge of the plate 40, that is, in the insertion direction when the spring member 4 is inserted into the downstream opening 31a. Opened at the upstream edge. An inclined edge portion 40b for guiding the reinforcing portion 31c into the notch portion 40a is provided upstream of the left and right edges of the notch portion 40a.

  The plate portion 40 of the spring member 4 is provided with an abutting portion 43 that abuts from the outside of the housing 3 against the reinforcing portion 31 c of the downstream housing component 31. The contact portion 43 is formed in a plate shape extending upward from the vicinity of the edge portion on the downstream side in the flow direction of the external air in the cutout portion 40a. The reinforcing portion 31c comes into contact with the surface of the contact portion 43 on the downstream side in the flow direction of the external air.

  Next, the structure of the left cap 5 and the right cap 6 will be described. The left cap 5 and the right cap 6 are made of a resin material having heat resistance and electrical insulation. As shown in FIG. 1, the left cap 5 covers the connection portion 12 b and the connection portion 13 b of the first to fourth heat generating portions A1 to A4, and the left end portions of the upstream housing constituent member 30 and the downstream housing constituent member 31. It is formed so as to cover. The right cap 6 is formed so as to cover the right end portions of the upstream housing component 30 and the downstream housing component 31. The left cap 5 and the right cap 6 are attached after the upstream housing component 30 and the downstream housing component 31 are combined.

  Next, an assembling procedure of the electric heater 1 configured as described above will be described. First, the first to fourth heat generating portions A1 to A4 and the fins 2 are stacked and placed on one member of the upstream housing constituent member 30 and the downstream housing constituent member 31. At this time, as shown in FIG. 10, the downstream upper engaging portion 20b and the upstream upper engaging portion 21b of the holder 14 of the first heat generating portion A1 are engaged with the upper electrode plate 12 from the upper side and the downstream side. Since the lower engaging portion 20c and the upstream lower engaging portion 21c are engaged from the lower side of the lower electrode plate 13, the upper electrode plate 12 and the lower electrode plate 13 do not fall off the holder 14. The PTC element 10 and the integrated state can be maintained. Therefore, when the first to fourth heat generating portions A1 to A4 are assembled to the housing 3 together with the fins 2, the assembling workability is improved. At this time, the spring member 4 is removed without being assembled.

  Then, the upstream housing component 30 and the downstream housing component 31 are combined. At this time, the fitting convex part 31b is inserted and fitted into the fitting concave part 30b, and the upstream housing constituent member 30 and the downstream housing constituent member 31 are integrated. Since the spring member 4 is removed when the upstream housing component 30 and the downstream housing component 31 are combined, the reaction force by the spring member 4 acts on the upstream housing component 30 and the downstream housing component 31. As a result, assembly workability is good.

  Thereafter, as shown in FIGS. 8 and 9, the spring member 40 is inserted into the housing 3 through the downstream opening 31 a of the housing 3. When inserting into the housing 3, the reaction force of the spring member 40 acts, but since the first to fourth heat generating parts A1 to A4 and the fins 2 are already held inside the housing 3, the spring member Only 4 should be pressed, and the assembly workability is good.

  After the spring member 4 is assembled, the compression force by the spring member 4 also acts on the first to fourth heat generating portions A1 to A4. At this time, as shown in FIG. 3, the upper electrode plate 12 held by the holder 14 can be displaced in a direction in which the upper electrode plate 12 is in contact with or separated from the lower electrode plate 13. Even if the plate 13 and the PTC element 10 vary in thickness and shape, the pressure contact force between the upper electrode plate 12 and the PTC element 10 and the pressure contact force between the lower electrode plate 13 and the PTC element 10 are sufficiently secured. It becomes possible. Thereby, the fall of the emitted-heat amount of the PTC element 10 can be suppressed.

  Further, when the spring member 4 is inserted into the housing 3, the spring member 4 can be assembled in a state in which the downstream reinforcing portion 31 c of the housing 3 is inserted into the cutout portion 40 a of the spring member 4. As a result, assembly workability is improved.

  Moreover, since the predetermined gap is provided between the reinforcing portions 30c and 31c of the housing 3 and the heat generating portions A1 to A4, it is possible to prevent the reinforcing portions 30c and 31c and the heat generating portions A1 to A4 from coming into strong contact. . Thereby, the compressive force by the spring member 4 can be made to act reliably on heat_generation | fever part A1-A4 and the fin 2. FIG.

  Moreover, since the contact part 43 which contact | abuts to the downstream reinforcement part 31c was provided in the spring member 4, insertion of the said spring member 4 can be stopped in the state which inserted the spring member 4 to the predetermined position.

  Note that the lower electrode plate 13 may be insert-molded into the holder 14 as in a modification of the embodiment shown in FIG. In this case, the lower electrode plate 13 is not displaced with respect to the holder 14, but the upper electrode plate 12 can allow displacement in a direction in which the lower electrode plate 13 is in contact with or separated from the lower electrode plate 13.

  The above-described embodiment is merely an example in all respects and should not be interpreted in a limited manner. Further, all modifications and changes belonging to the equivalent scope of the claims are within the scope of the present invention.

  As described above, the electric heater according to the present invention can be used, for example, as an air heater of a vehicle air conditioner.

DESCRIPTION OF SYMBOLS 1 Electric heater 2 Fin 3 Housing 4 Spring member 12 Upper electrode plate (1st electroconductive member)
13 Lower electrode plate (second conductive member)
14 Holder 20b Downstream-side upper engagement part (first engagement part)
20c Downstream-side lower engaging portion (second engaging portion)
20d downstream protrusion 21b upstream upper engagement part (first engagement part)
21c Upstream lower engagement part (second engagement part)
21d Upstream side protrusion 30 Upstream housing component 31 Downstream housing component A1 to A4 First to fourth heating elements

Claims (6)

A heat generating part having a heat generating element that generates heat by supplying power;
Fins for transferring heat of the heat generating part to external air;
A housing for holding the heat generating portion and the fin in a state in which the heat generating portion and the fin are stacked in a direction intersecting with the flow direction of the external air;
An electric heater that is assembled to the housing and includes a spring member for applying a compressive force in the stacking direction to the heat generating portion and the fin.
The heat generating part is arranged so as to sandwich the heat generating element from both sides in the stacking direction and to be in contact with the heat generating element so as to supply electric power to the heat generating element from the outside. A member and a holder for holding the heating element, the first conductive member, and the second conductive member;
The holder includes a first engagement portion that engages with the first conductive member from the side opposite to the heating element side, and a holder that engages with the second conductive member from the side opposite to the heating element side. A second engaging portion to be joined,
The holder is configured to allow displacement of the first conductive member in a direction in which the first conductive member is in contact with or separated from the second conductive member between the first engagement portion and the second engagement portion. An electric heater characterized by that. The electric heater according to claim 1,
The holder has a frame shape surrounding the periphery of the first conductive member and the second conductive member,
The electric heater according to claim 1, wherein each of the first engaging portion and the second engaging portion includes a protrusion protruding from an inner surface of the holder toward an inner side of the holder. The electric heater according to claim 2,
The holder is made of resin material,
The electric heater, wherein the first engaging portion and the second engaging portion are arranged so as not to overlap each other when the holder is viewed from the stacking direction. The electric heater according to any one of claims 1 to 3,
The electric heater, wherein the second conductive member is insert-molded in the holder. The electric heater according to any one of claims 1 to 3,
The holder is configured to allow displacement of the second conductive member in a direction in which the second conductive member comes into contact with and separates from the first conductive member between the first engagement portion and the second engagement portion. An electric heater characterized by that. The electric heater according to claim 2 or 3,
On the inner surface of the holder, there is provided a protrusion that protrudes inward of the holder from between the first engagement portion and the second engagement portion,
The electric heater according to claim 1, wherein a dimension of the protruding portion in the stacking direction is set to be shorter than a dimension of the heating element in the stacking direction.

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