Resistor

Abstract

The invention provides a resistor capable of dispersing stress applied to a housing. This resistor is provided with: a resistor element that has a resistor body having a rectangular columnar main body part on which a pair of side planes facing away from each other are formed, and a pair of mounted parts positioned at both ends of the main body part, a pair of mounting parts mounted to the pair of mounted parts, and a pair of terminal plates; and a housing having a pair of terminal plates provided on the pair of mounting portions, the housing having a pair of side walls, an opening formed at the upper ends of the pair of side walls, a bottom wall provided at the lower ends of the side walls, and an accommodation space surrounded by the pair of side walls and the bottom wall to accommodate the resistor body, the resistor is housed in the housing space such that the pair of side planes face each other in parallel with the inner planes of the pair of side walls.

Description

Technical Field

[0001] The present invention relates to resistors. Background Art

[0002] Patent Document 1 discloses a resistor including a cylindrical insulator, a pair of mounting terminals with terminal plates provided at both ends of the insulator, and a case having an opening on one side and accommodating the insulator with the terminal plates protruding from the opening to the outside.

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Laid-Open No. 11-195503 Summary of the invention

[0006] Technical problem to be solved by the invention

[0007] In the resistor described in Patent Document 1, the housing space of the housing that houses the insulator is roughly rectangular in cross-sectional view, while the insulator is circular, so the shapes of the two are greatly different. In addition, when such a resistor is used for pre-charging of electric vehicles, hybrid vehicles, etc., when the resistor is heated instantly, stress is easily concentrated on the side wall of the housing due to the linear expansion of the resistance wire and the insulator, so there is a risk of cracks in the housing, etc.

[0008] The present invention has been made in view of this problem, and an object of the present invention is to provide a resistor capable of dispersing stress applied to a housing.

[0009] Solutions for solving technical problems

[0010] According to an embodiment of the present invention, a resistor is provided, wherein the resistor comprises a resistor element and a box-shaped shell, wherein the resistor element comprises: a resistor body having a prismatic main body portion having a pair of side surfaces facing each other and a pair of mounted portions located at both ends of the main body portion, a pair of mounting portions respectively mounted on the pair of mounted portions; and a pair of terminal plates respectively arranged on the mounted portions through the pair of mounting portions, wherein the box-shaped shell comprises a pair of side walls extending in a height direction when viewed in a cross-sectional view, an opening formed at one end of the pair of side walls, a bottom wall arranged at the other end of the pair of side walls in a manner extending in a width direction when viewed in a cross-sectional view, and an accommodating space formed by the pair of side walls and the bottom wall to accommodate the resistor body, wherein the resistor body is accommodated in the accommodating space via a sealing material in a manner in which the pair of side surfaces are respectively opposed to the inner side surfaces of the pair of side walls.

[0011] Effects of the Invention

[0012] According to the aspect of the present invention, it is possible to disperse the stress applied to the housing. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is an exploded view of the structure of the resistor involved in this embodiment.

[0014] Figure 2 It is a perspective view of the resistor according to the present embodiment, in which the sealing material is omitted.

[0015] Figure 3 It is along Figure 2 A schematic cross-sectional view of line III-III in FIG. 2 , omitting the terminal portion and the resistor wire.

[0016] Figure 4 It is along Figure 1 Cross-sectional view along line IV-IV in FIG.

[0017] Figure 5 This is a front view of the resistor element with the terminal portion and the resistor wire omitted.

[0018] Figure 6 This is a front view of the resistor element with the resistor wire omitted.

[0019] Figure 7 It is a schematic cross-sectional view of the resistor according to the first modification, in which the terminal portion and the resistor wire are omitted.

[0020] Figure 8 It is a schematic cross-sectional view of a resistor according to a second modification, in which a terminal portion and a resistor wire are omitted.

[0021] Fig. 9 It is a perspective view of a resistor element according to a third modification.

[0022] Fig.10 It is a partial perspective view of a resistor element according to a fourth modification.

[0023] Description of Reference Numerals

[0024] 1: resistor, 2: resistor element, 3: housing, 4: cement material (sealing material), 21: resistor body, 22: mounting portion, 23: terminal board, 31: side wall, 32: opening, 33: bottom wall, 211: main body, 211a: one side plane, 211b: another side plane, 212: mounted portion, 311: inner plane, S: accommodating space. DETAILED DESCRIPTION

[0025] Hereinafter, a method for implementing the present invention (hereinafter, also referred to as an embodiment) will be described with reference to the accompanying drawings. In this specification, the same elements are marked with the same reference numerals as a whole. It should be noted that in the accompanying drawings, the length direction, width direction, and height direction of the resistor 1 (housing 3) are respectively set as the direction along the X-axis, the direction along the Y-axis, and the direction along the Z-axis. Hereinafter, for the convenience of description, the length direction, width direction, and height direction of the resistor 1 are referred to as the length direction, width direction, and height direction.

[0026] First, refer to Figures 1 to 5 The configuration of the resistor 1 according to the present embodiment will be described.

[0027] Figure 1 It is an exploded view showing the structure of the resistor 1 according to the present embodiment. Figure 2 It is a perspective view of the resistor 1 according to the present embodiment, and the cement material 4 is omitted. Figure 3 It is along Figure 2 In the schematic cross-sectional view taken along line III-III in FIG. 1 , the terminal portion and the resistor wire 24 are omitted and only the main portion is shown. Figure 4 It is along Figure 1 Cross-sectional view along line IV-IV in FIG. Figure 5 It is a front view of the resistor element 2 in a state where the terminal portion and the resistor wire 24 are omitted. Figure 6 It is a front view of the resistor element 2 in a state where the resistor wire 24 is omitted.

[0028] like Figures 1 to 6 As shown, the resistor 1 includes a resistor element 2, a box-shaped housing 3 that accommodates a portion of the resistor element 2 (i.e., a resistor body 21 described later), and a cement material 4 as a sealing material that seals the housing 3 in a state where a portion of the resistor element 2 is accommodated in the housing 3 (see Figure 3 ). In addition, in this embodiment, the resistor 1 is used for pre-charging of electric vehicles, hybrid vehicles, etc.

[0029] like Figure 1 As shown, the resistor element 2 includes a resistor body 21, a pair of mounting portions 22, a pair of terminal plates 23, and a resistor wire 24. It should be noted that the pair of terminal portions are respectively constituted by a pair of mounting portions 22 and a pair of terminal plates 23.

[0030] In the present embodiment, the resistor element 2 includes a resistor body 21, a pair of mounting portions 22, a pair of terminal plates 23, and a resistor wire 24, but the present invention is not limited thereto, and for example, a resistor coating formed on the outer peripheral surface of the resistor body 21 may be used instead of the resistor wire 24. In this case, the resistor coating is composed of a metal coating, a carbon coating, a metal glaze coating, an oxidized metal coating, or the like.

[0031] The resistor 21 is an insulator, which is made of an insulator such as ceramic or a glass fiber bundle. Figure 4 As shown, the resistor 21 has a main body 211 in a prismatic shape (specifically, a rectangular column shape, more specifically, a square column shape) and a pair of mounted portions 212 in which a pair of mounting portions 22 of a pair of terminal portions are respectively fitted.

[0032] like Figure 3 As shown, the main body 211 has a pair of side planes 211a and 211b as side surfaces facing each other, and a top plane 211c as a top surface and a bottom plane 211d as a bottom surface facing each other in a manner orthogonal to the pair of side planes 211a and 211b. In addition, from the perspective of easily winding the resistance wire 24 around the outer periphery of the main body 211, it is preferred to form R surfaces at the four corners of the main body 211.

[0033] like Figure 1 and Figure 4 As shown, a pair of mounted portions 212 are formed integrally with the main body 211 in a manner of being located at both ends of the main body 211. In this embodiment, the pair of mounted portions 212 are configured as a cylindrical shape. In contrast, in the case where the pair of mounted portions are configured as a rectangular column, when the pair of mounted portions are slightly twisted, the pair of terminal portions are bent corresponding to the twisting of the pair of mounted portions to be inserted. Therefore, according to the mounted portion 212 involved in this embodiment, it is easy to improve the position accuracy of the terminal portion compared to the mounted portion configured as a rectangular column.

[0034] like Figure 4 and Figure 5 As shown in FIG. 2 , a step is formed between the main body 211 and the mounted portion 212, which is formed by the end surface 211e of the main body 211 exposed from the mounted portion 212. Figure 5 As shown, when viewed from the front, the mounted portion 212 is arranged such that the axis of the mounted portion 212 coincides with the axis of the main body 211 and the mounted portion 212 is located inside the main body 211 .

[0035] In addition, from the perspective of minimizing the stress difference on the housing 3 caused by the different shapes of the main body 211 and the mounted portion 212, the ratio of the cross-sectional area of ​​the mounted portion 212 to the cross-sectional area of ​​the main body 211 is preferably greater than 0.8.

[0036] like Figure 1 , Figure 4 as well as Figure 6 As shown, the pair of mounting parts 22 of the pair of terminal parts are respectively mounted on the pair of mounted parts 212. In this embodiment, the pair of mounting parts 22 are a pair of metal cap terminals configured as bottomed cylindrical shapes. It should be noted that the pair of mounting parts 22 are configured of, for example, iron or copper.

[0037] Each mounting portion 22 has a peripheral wall 221 formed to have a uniform thickness d. In addition, the thickness d of the peripheral wall 221 is formed to be greater than the minimum height h of the step (i.e., the minimum distance between the outer peripheral surface of the mounted portion 212 and the outer peripheral surface of the main body portion 211, see Figure 4 Specifically, the minimum height h of the step is greater than 1 / 3 of the thickness d of the peripheral wall 221 and is smaller than the thickness d of the peripheral wall 221. Figure 6 As shown, when each mounting portion 22 is mounted on each mounted portion 212, each mounting portion 22 has a weldable region 222 that protrudes outwardly from a side plane 211a on one side of the main body 211. It should be noted that, in the present embodiment, the weldable region 222 protrudes outwardly from a side plane 211a on one side of the main body 211, but is not limited thereto, and for example, may protrude outwardly from a side plane 211b, a top plane 211c, or a bottom plane 211d on the other side of the main body 211.

[0038] like Figure 1 and Figure 4 As shown, a pair of terminal plates 23 are respectively arranged on the mounted portion 212 through a pair of mounting portions 22. The pair of terminal plates 23 are composed of a conductive metal plate. Specifically, the pair of terminal plates 23 are composed of, for example, iron or copper. In addition, in the present embodiment, the pair of terminal plates 23 are respectively formed integrally with the pair of mounting portions 22, but are not limited thereto. For example, they may be respectively joined to the pair of mounting portions 22 by welding or the like. In addition, a protrusion for positioning a portion of the pair of terminal plates 23 in the accommodating space S of the housing 3 may also be provided on the pair of terminal plates 23.

[0039] The resistance wire 24 is made of a conductive metal wire material, such as nickel-iron alloy (Ni-Fe), copper-nickel alloy (Cu-Ni), nickel (Ni), chromium (Cr), or nickel-chromium alloy (Ni-Cr).

[0040] like Figure 1 and Figure 4 As shown, the resistance wire 24 is wound around the outer peripheral surface of the main body 211 in such a manner that the end 241 is fixed to the weldable region 222 by welding. In addition, as described above, since the weldable region 222 protrudes further outward than the side plane 211a of one side of the main body 211, when the resistance wire 24 is wound around the outer peripheral surface of the main body 211 (i.e., the low position / inner position) from the weldable region 222 (i.e., the high position / outer position), the load in the peeling direction at the welded point formed by welding the end 241 and the weldable region 222 can be reduced (see Figure 1 The arrow R, specifically, the radial direction orthogonal to the weldable area 222).

[0041] As described above, since the thickness d of the peripheral wall 221 is formed to be larger than the minimum height h of the step, the dimensions of the resistor body 21 in the width direction and the height direction after winding are less likely to be affected by the diameter of the resistor wire 24, compared with the case where the thickness d of the peripheral wall 221 is less than the minimum height h of the step. The reason is that when the minimum height h of the step becomes larger relative to the thickness d of the peripheral wall 221, when the resistance value is changed without changing the size of the main body 211, only the diameter of the resistor wire 24 is changed, and the outermost diameter of the resistor body 21 is affected by the difference in the diameter of the resistor wire 24, and the dimensions of the resistor body 21 in the width direction and the height direction change, so that it may contact with the housing 3 or cause a design defect.

[0042] Then, if Figure 1 and Figure 3 As shown, the housing 3 is a top-open box-type housing made of ceramics, etc. It should be noted that in this embodiment, the housing 3 is made of ceramics, etc., but is not limited thereto, and may be made of, for example, resin material, alumina or metal material.

[0043] The shell 3 has: a pair of side walls 31, which extend along the height direction when viewed in cross section and are opposite to the two side surfaces of the terminal plate 23; an opening 32, formed at the upper end of one end of the pair of side walls 31; a bottom wall 33, which is formed at the lower end of the other end of the pair of side walls 31 in a manner extending along the width direction when viewed in cross section; a pair of end walls 34, which connect the pair of side walls 31; and a storage space S, which is surrounded by a pair of side walls 31, a bottom wall 33 and a pair of end walls 34, and the storage space S accommodates the resistor 21.

[0044] The pair of side walls 31 has inner planes 311a and 311b as a pair of inner side surfaces parallel to each other. In addition, when the resistor 21 is accommodated in the accommodation space S of the housing 3 via the cement material 4, the pair of side planes 211a and 211b of the main body 211 are respectively arranged parallel to the pair of inner planes 311a and 311b. As a result, since the distance between the side plane 211a on one side and the inner plane 311a on one side (or the distance between the side plane 211b on the other side and the inner plane 311b on the other side) can be made uniform, the stress applied from the main body 211 to each side wall 31 of the housing 3 can be dispersed compared to the case where the cylindrical main body is accommodated in the housing 3. In addition, the left-right and front-back twisting of the terminal portion can be suppressed.

[0045] In this embodiment, a pair of inner side surfaces are composed of inner planes 311a and 311b that are parallel to each other, but are not limited to this. For example, they can also be composed of a pair of inclined surfaces or a pair of curved surfaces that are formed in a manner such that the distance between the two decreases as the distance between them moves from the upper end side of the side wall 31 toward the lower end side of the side wall 31.

[0046] In addition, from the viewpoint of evenly dispersing the stress applied from the main body 211 to each side wall 31 of the housing 3, the ratio of the first distance p1 to the second distance p2, i.e., the first ratio, is preferably between 0.8 and 1.2, and more preferably between 0.9 and 1.1. The first distance p is the distance between the side plane 211a on one side and the inner plane 311a of the side wall 31a on one side (see Figure 3 , hereinafter also referred to as the first distance p1), the second distance p2 is the distance between the other side plane 211b and the inner side plane 311b of the other side wall 31b (refer to Figure 3 , hereinafter, also referred to as the second distance p2). Further, the first ratio is most preferably 1.0, that is, the first distance p1 is consistent with the second distance p2.

[0047] Furthermore, when the first ratio is less than 0.8, the side plane 211a on one side is too close to the inner plane 311a on one side, resulting in that the stress applied from the main body 211 to the side wall 31a on one side is more concentrated than the stress applied to the side wall 31b on the other side, thereby increasing the risk of cracks occurring in the side wall 31a on one side. On the other hand, when the first ratio is greater than 1.2, the side plane 211b on the other side is too close to the inner plane 311b on the other side, resulting in that the stress applied from the main body 211 to the side wall 31b on the other side is more concentrated than the stress applied to the side wall 31a on one side, thereby increasing the risk of cracks occurring in the side wall 31b on the other side.

[0048] In addition, the pair of side walls 31 is configured to have a substantially uniform thickness. Thus, since the distance from one side plane 211a to the outer plane 312a of one side wall 31a (or the distance from the other side plane 211b to the outer plane 312b of the other side wall 31b) can be made uniform, when the resistor 1 is instantaneously heated, the heat dissipation (heat escape, heat dispersion) from the main body 211 of the resistor 21 to the outside of the side wall 31 of the housing 3 can be stabilized.

[0049] The opening 32 is a portion of the housing 3 that is opened, and corresponds to a boundary between the outside and the storage space S of the housing 3 . The lower ends of the pair of terminal plates 23 , which are base ends, are stored in the storage space S via the opening 32 .

[0050] The bottom wall 33 has an inner plane 331 that is orthogonal to the inner planes 311a and 311b of the pair of side walls 31. In addition, when the resistor 21 is accommodated in the accommodation space S of the housing 3 via the cement material 4, the bottom plane 211d of the main body 211 and the inner plane 331 of the bottom wall 33 are parallel and opposite to each other. As a result, since the distance between the bottom plane 211d of the main body 211 and the inner plane 331 of the bottom wall 33 can be made uniform (described later), the stress applied from the main body 211 to the bottom wall 33 of the housing 3 can be dispersed compared to the case where the cylindrical main body is accommodated in the housing 3.

[0051] In addition, from the viewpoint of evenly dispersing the stress applied from the main body 211 to the walls 31 and 33 of the housing 3, the ratio of the first distance p1 to the third distance p3, i.e., the second ratio, is preferably between 0.8 and 1.2, and more preferably between 0.9 and 1.1. The first distance p1 is the distance between the side plane 211a on one side and the inner plane 311a of the side wall 31a on one side (see Figure 3 ), the third distance p3 is the distance between the bottom plane 211d of the main body 211 and the inner plane 331 of the bottom wall 33 (refer to Figure 3 , hereinafter, also referred to as the third distance p3). Further, the second ratio is most preferably 1.0, that is, the first distance p1 is consistent with the third distance p3.

[0052] In addition, when the second ratio is less than 0.8, the side plane 211a on one side is too close to the inner plane 311a on one side, resulting in that the stress applied from the main body 211 to the side wall 31a on one side is more concentrated than the stress applied to the bottom wall 33, thereby increasing the risk of cracks in the side wall 31a on one side. On the other hand, when the second ratio is greater than 1.2, the bottom plane 211d of the main body 211 and the inner plane 331 of the bottom wall 33 are too close, resulting in that the stress applied from the main body 211 to the bottom wall 33 is more concentrated than the stress applied to the side wall 31a on one side, thereby increasing the risk of cracks in the bottom wall 33.

[0053] In addition, from the viewpoint of evenly dispersing the stress applied from the main body 211 to the walls 31 and 33 of the housing 3, the ratio of the second distance p2 to the third distance p3, i.e., the third ratio, is preferably between 0.9 and 1.1, and more preferably between 0.95 and 1.05. The second distance p2 is the distance between the other side plane 211b and the inner side plane 311b of the other side wall 31b (see Figure 3 ), the third distance p3 is the distance between the bottom plane 211d of the main body 211 and the inner plane 331 of the bottom wall 33 (refer to Figure 3 ). Further, the third ratio is most preferably 1.0, that is, the second distance p2 is consistent with the third distance p3.

[0054] In addition, when the third ratio is less than 0.9, the other side plane 211b and the other inner plane 311b are too close to each other, resulting in that the stress applied from the main body 211 to the other side wall 31b is more concentrated than the stress applied to the bottom wall 33, and the risk of cracks in the other side wall 31b becomes higher. On the other hand, when the third ratio is higher than 1.1, the bottom plane 211d of the main body 211 and the inner plane 331 of the bottom wall 33 are too close to each other, resulting in that the stress applied from the main body 211 to the bottom wall 33 is more concentrated than the stress applied to the other side wall 31b, and the risk of cracks in the bottom wall 33 becomes higher.

[0055] In addition, the bottom wall 33 is configured to have a uniform thickness. Thus, since the distance from the bottom plane 211d of the main body 211 to the outer plane 332 of the bottom wall 33 can be made uniform, when the resistor 1 is heated instantaneously, the heat dissipation from the main body 211 of the resistor 21 to the outside of the bottom wall 33 of the housing 3 can be stabilized. It should be noted that the thickness of the bottom wall 33 is preferably consistent with the thickness of the side wall 31. Thus, when the resistor 1 is heated instantaneously, the heat dissipation from the main body 211 of the resistor 21 to the outside of the housing 3 can be stabilized.

[0056] As described above, the resistor 21 is housed in the housing space S of the housing 3 via the cement material 4 in such a manner that the pair of side planes 211a, 211b and the bottom plane 211d of the main body 211 are parallel to and opposed to the pair of inner planes 311a, 311b and the inner plane 331 of the bottom wall 33, respectively. Thus, compared with the case where the cylindrical main body is housed in the housing 3, the housing space S of the housing 3 can be effectively utilized, so that the capacity (volume) of the resistor wire 24 can be sufficiently ensured. As a result, the pulse resistance characteristics of electric vehicles, hybrid vehicles, etc. are improved.

[0057] In addition, compared with the case where the cylindrical main body is accommodated in the shell 3, the amount of cement material 4 filled between the outer side of the main body 211 and the inner side of the shell 3 can be reduced, thereby suppressing the generation of cracks in the shell 3 due to thermal expansion of the cement material 4.

[0058] The pair of end walls 34 are respectively opposed to the pair of mounting portions 22. In addition, a gap is formed between each end wall 34 and each mounting portion 22. Thus, damage to each mounting portion 22 caused by the abutment between each end wall 34 and each mounting portion 22 can be prevented.

[0059] In addition, in order to maintain the strength of the housing 3 while not making the outer shape of the housing 3 too large and to maximize the accommodation space S, as shown in FIG. Figure 3As shown, each corner of the storage space S is formed into a rounded shape. As a result, since the strength of the housing 3 can be maintained, the influence of thermal expansion can be alleviated and cracks are less likely to occur at each corner of the storage space S.

[0060] (Variation)

[0061] Next, refer to Figures 7 to 10 A resistor 1 according to a modification example will be described. Note that, in the modification example, points identical to the above-described embodiment are omitted, and points different from the above-described embodiment will be mainly described.

[0062] Figure 7 It is a schematic cross-sectional view of the resistor 1 according to the first modified example, in which the terminal portion and the resistor wire 24 are omitted and only the main portion is shown. Figure 8 It is a schematic cross-sectional view of the resistor 1 according to the second modification, in which the terminal portion and the resistor wire 24 are omitted and only the main portion is shown. Fig. 9 It is a perspective view of a resistor element 2 according to a third modification. Fig.10 It is a partial perspective view of the resistor element 2 according to the fourth modification.

[0063] In the above-mentioned embodiment, a pair of side surfaces are respectively constituted by a pair of side planes 211a and 211b, but it is not limited thereto. Figure 7 As shown, it may be composed of a first curved surface 211A and a second curved surface 211B as a pair of curved surfaces that protrude toward the inner side surfaces of the pair of side walls 31 in a cross-sectional view. It should be noted that the first curved surface 211A and the second curved surface 211B have the same curvature.

[0064] In this case, if Figure 7 As shown, R surfaces C are formed at the four corners of the square columnar main body 211. Specifically, a first R surface C1, a second R surface C2, a third R surface C3, and a fourth R surface C4 are formed at the upper right corner of the main body 211, the lower right corner of the main body 211, the upper left corner of the main body 211, and the lower left corner of the main body 211. It should be noted that the first R surface C1, the second R surface C2, the third R surface C3, and the fourth R surface C4 have the same curvature.

[0065] The first curved surface 211A as one curved surface is formed to be located between the first R surface C1 and the second R surface C2. Specifically, the first curved surface 211A is formed so that, when viewed in a cross-sectional view, the upper end as one end is connected to the lower end of the first R surface C1, and the lower end as the other end is connected to the upper end of the second R surface C2. In addition, when viewed in a cross-sectional view, the first curved surface 211A is formed so that the curvature is different from the curvatures of the first R surface C1 and the second R surface C2.

[0066] The upper end of the first curved surface 211A is located closer to the opening 32 side than the bottom wall 33 side, that is, separated from the bottom wall 33 side. In addition, the lower end of the first curved surface 211A is located closer to the bottom wall 33 side than the opening 32 side, that is, separated from the opening 32 side. In addition, a virtual straight line L1 connecting the upper end and the lower end (that is, both ends) of the first curved surface 211A is formed to extend in the height direction.

[0067] Similarly, the second curved surface 211B as the other curved surface is formed to be located between the third R surface C3 and the fourth R surface C4. Specifically, the second curved surface 211B is formed so that, when viewed in a cross-sectional view, the upper end is connected to the lower end of the third R surface C3, and the lower end is connected to the upper end of the fourth R surface C4. In addition, when viewed in a cross-sectional view, the second curved surface 211B is formed so that the curvature is different from the curvatures of the third R surface C3 and the fourth R surface C4.

[0068] The upper end of the second curved surface 211B is located closer to the opening 32 side than the bottom wall 33 side, that is, separated from the bottom wall 33 side. In addition, the lower end of the second curved surface 211B is located closer to the bottom wall 33 side than the opening 32 side, that is, separated from the opening 32 side. Another imaginary straight line L2 connecting the upper end and the lower end (that is, both ends) of the second curved surface 211B is formed to extend in the height direction.

[0069] In addition, from the viewpoint of evenly dispersing the heat and stress applied from the main body 211 to the side wall 31a of the housing 3 and making it easy to wind the resistance wire 24 in a state of being closely attached to the outer peripheral surface of the main body 211, the ratio of the maximum first distance p1max to the minimum first distance p1min is preferably greater than 1.0 and less than 2.5, and more preferably between 1.3 and 2.0. The maximum first distance p1max is the distance between the upper end of the first curved surface 211A and the inner plane 311a of the side wall 31a (see Figure 7 , hereinafter also referred to as the maximum first distance p1max), the minimum first distance p1min is the distance between the vertex of the first curved surface 211A and the inner plane 311a of one side wall 31a (refer to Figure 7 , hereinafter also referred to as the minimum first distance p1min).

[0070] Furthermore, when the ratio of the maximum first distance p1max to the minimum first distance p1min is 1.0, since the side surface becomes a side plane instead of the first curved surface 211A, it is difficult to make the resistance wire 24 close to the outer peripheral surface of the main body 211. On the other hand, when the ratio of the maximum first distance p1max to the minimum first distance p1min is higher than 2.5, it is difficult to evenly disperse the heat and stress applied from the main body 211 to the side wall 31a on one side.

[0071] Similarly, from the viewpoint of evenly dispersing the heat and stress applied from the main body 211 to the other side wall 31b of the housing 3 and making it easy to wind the resistance wire 24 in a state of being closely attached to the outer peripheral surface of the main body 211, the ratio of the maximum second distance p2max to the minimum second distance p2min is preferably greater than 1.0 and less than 2.5, and more preferably between 1.3 and 2.0. The maximum second distance p2max is the distance between the upper end of the second curved surface 211B and the inner plane 311b of the other side wall 31b (see Figure 7 , hereinafter also referred to as the maximum second distance p2max), the minimum second distance p2min is the distance between the vertex of the second curved surface 211B and the inner plane 311b of the other side wall 31b (refer to Figure 7 , hereinafter also referred to as the minimum second distance p2min).

[0072] Furthermore, when the ratio of the maximum second distance p2max to the minimum second distance p2min is 1.0, since the side surface becomes a side plane instead of the second curved surface 211B, it is difficult to make the resistance wire 24 close to the outer peripheral surface of the main body 211. On the other hand, when the ratio of the maximum second distance p2max to the minimum second distance p2min is higher than 2.5, it is difficult to evenly disperse the heat and stress applied from the main body 211 to the other side wall 31b.

[0073] In addition, from the viewpoint of evenly dispersing the heat and stress applied from the main body 211 to each side wall 31 of the housing 3, the ratio of the maximum first distance p1max to the maximum second distance p2max, i.e., the maximum first ratio, is preferably between 0.8 and 1.2, and more preferably between 0.9 and 1.1. Furthermore, the maximum first ratio is most preferably 1.0, i.e., the maximum first distance p1max is consistent with the maximum second distance p2max.

[0074] Furthermore, from the viewpoint of evenly dispersing the heat and stress applied from the main body 211 to each side wall 31 of the housing 3, the ratio of the minimum first distance p1min to the minimum second distance p2min, i.e., the minimum first ratio, is preferably between 0.8 and 1.2, and more preferably between 0.9 and 1.1. Furthermore, the minimum first ratio is most preferably 1.0, i.e., the minimum first distance p1min is consistent with the minimum second distance p2min.

[0075] In the first modified example, the top surface and the bottom surface are respectively formed by a third curved surface 211C protruding toward the opening 32 and a fourth curved surface 211D protruding toward the bottom wall 33. Thus, it is easy to wind the resistance wire 24 around the outer peripheral surface of the main body 211. It should be noted that the first curved surface 211A, the second curved surface 211B, the third curved surface 211C, and the fourth curved surface 211D have the same curvature.

[0076] The third curved surface 211C is formed to be located between the first R-surface C1 and the third R-surface C3. Specifically, the third curved surface 211C is formed such that, when viewed in a cross-sectional view, the right end is connected to the left end of the first R-surface C1, and the left end is connected to the right end of the third R-surface C3. In addition, when viewed in a cross-sectional view, the third curved surface 211C is formed to have a curvature different from that of the first R-surface C1 and the third R-surface C3.

[0077] The fourth curved surface 211D is formed to be located between the second R-surface C2 and the fourth R-surface C4. Specifically, the fourth curved surface 211D is formed such that, when viewed in a cross-sectional view, the right end is connected to the left end of the second R-surface C2, and the left end is connected to the right end of the fourth R-surface C4. In addition, when viewed in a cross-sectional view, the fourth curved surface 211D is formed to have a curvature different from that of the second R-surface C2 and the fourth R-surface C4.

[0078] Similarly, from the viewpoint of evenly dispersing the heat and stress applied from the main body 211 to the bottom wall 33 of the housing 3 and making it easy to wind the resistance wire 24 in a state of being closely attached to the outer peripheral surface of the main body 211, the ratio of the maximum third distance p3max to the minimum third distance p3min is preferably greater than 1.0 and less than 2.5, and more preferably between 1.3 and 2.0. The maximum third distance p3max is the distance between the end of the fourth curved surface 211D and the inner plane 331 of the bottom wall 33 (see Figure 7 , hereinafter also referred to as the maximum third distance p3max), the minimum third distance p3min is the distance between the vertex of the fourth curved surface 211D and the inner plane 331 of the bottom wall 33 (refer to Figure 7 , hereinafter also referred to as the minimum third distance p3min).

[0079] Furthermore, when the ratio of the maximum third distance p3max to the minimum third distance p3min is 1.0, since the side surface becomes a side plane instead of the fourth curved surface 211D, it is difficult to wind the resistance wire 24 in a state of being closely attached to the outer peripheral surface of the main body 211. On the other hand, when the ratio of the maximum third distance p3max to the minimum third distance p3min is higher than 2.5, it is difficult to evenly disperse the heat and stress applied from the main body 211 to the bottom wall 33.

[0080] In addition, in the above-mentioned embodiment, the main body 211 is configured as a rectangular column when viewed in cross section, but is not limited thereto. Figure 8 As shown in FIG. 1 , the main body 211 may be formed in an octagonal column shape when viewed in cross section. In this case, it is easier to wind the resistor wire 24 around the main body 211 than when the main body 211 is formed in a rectangular column shape.

[0081] In addition, in the above-mentioned embodiment, the mounted portion 212 and the mounting portion 22 are respectively configured as a columnar shape and a bottomed cylindrical shape, but are not limited thereto. Fig. 9 As shown, they may be respectively configured in a prism shape (specifically, a rectangular column shape) and a square tube shape with a bottom (specifically, a rectangular tube shape with a bottom).

[0082] In this case, since the main body 211 and the mounted portion 212 constituting the resistor 21 are both configured in a prismatic shape, the main body 211 and the mounted portion 212 have almost no difference in shape, and the stress difference caused thereby can be suppressed. In addition, the outer peripheral surfaces of the mounted portion 212 are arranged in a manner parallel to and opposite to the inner peripheral surfaces of the housing 3, similarly to the outer peripheral surfaces of the main body 211. Thus, compared with the case where a cylindrical mounted portion is accommodated in the housing 3, the stress applied to the housing 3 from the mounted portion 212 can be dispersed.

[0083] In the third modification example, the mounting portion 22 is formed of a cap terminal having a bottomed square tube shape, but the present invention is not limited thereto. Fig.10 As shown, it can also be composed of clip terminals.

[0084] In this case, if Fig.10 As shown, the upper and lower surfaces of the mounted portion 212 are clamped by the clamping portion 223 of the mounting portion 22. Also, the mounting portion 22 has a weldable region 222 protruding outward from one side plane 211a of the main body 211, similarly to the above-described embodiment.

[0085] Furthermore, in the above-described embodiment, the two mounting portions 22 are formed of two cap terminals, but the present invention is not limited thereto, and for example, the mounting portions 22 may be formed of a combination of one cap terminal and one clip terminal.

[0086] (Effect)

[0087] Next, the effects of the embodiment and the modified examples will be described.

[0088] The resistor 1 according to the above-mentioned embodiment includes a resistor element 2 and a box-shaped housing 3. The resistor element 2 includes a resistor body 21, a pair of mounting portions 22, and a pair of terminal plates 23. The resistor body 21 includes a rectangular columnar main body 211 having a pair of side planes 211a and 211b facing each other, and a pair of mounted portions 212 located at both ends of the main body 211. The pair of mounting portions 22 are respectively mounted on the pair of mounted portions 212. The pair of terminal plates 23 are respectively connected to the resistor body 211 by a pair of mounting portions 22. The box-shaped shell 3 is arranged on the mounted portion 212 relative to the mounting portion 22, and has a pair of side walls 31, an opening 32 formed at the upper ends of the pair of side walls 31, a bottom wall 33 arranged at the lower ends of the side walls 31, and an accommodating space S surrounded by the pair of side walls 31 and the bottom wall 33 to accommodate the resistor 21. The resistor 21 is accommodated in the accommodating space S via the cement material 4 in a manner that a pair of side planes 211a and 211b are respectively opposed to the inner planes 311a and 311b of the pair of side walls 31.

[0089] According to this configuration, since the distance between the side plane 211a on one side and the inner plane 311a on one side (or the distance between the side plane 211b on the other side and the inner plane 311b on the other side) can be made uniform, the stress applied from the main body 211 to the side walls 31 of the housing 3 can be dispersed compared to the case where the cylindrical main body is accommodated in the housing 3. In addition, the torsion of the terminal portion can be suppressed. In addition, since the distance from the heat-generating resistor element 2 to the side walls 31 of the housing 3 can be made shorter overall compared to the case where the cylindrical main body is accommodated in the housing 3, the generated heat can be dispersed, and heat concentration can be suppressed.

[0090] In the first modified example described above, the pair of side surfaces are respectively composed of a pair of first curved surfaces 211A and a second curved surface 211B protruding toward the inner side surfaces of the pair of side walls 31. When viewed in cross section, a pair of imaginary straight lines L1 and L2 respectively connecting the two ends of the pair of first curved surfaces 211A and the second curved surface 211B extend in the height direction, and the distance between the upper end of the first curved surface 211A and the inner plane 311a of one side wall 31a, that is, the maximum first distance p1max and the first curved surface 211A is equal to the maximum first distance p1max. The ratio of the distance between the vertex of surface 211A and the inner plane 311a of the side wall 31a on one side, i.e., the minimum first distance p1min, is greater than 1.0 and is less than 2.5, and the ratio of the distance between the upper end of the second curved surface 211B and the inner plane 311b of the other side wall 31b, i.e., the maximum second distance p2max, and the distance between the vertex of the second curved surface 211B and the inner plane 311b of the other side wall 31b, i.e., the minimum second distance p2min, is greater than 1.0 and is less than 2.5.

[0091] According to this configuration, the heat and stress applied from the main body 211 to the side walls 31 of the case 3 are evenly dispersed, and the resistance wire 24 can be easily wound in a state of being in close contact with the outer peripheral surface of the main body 211 .

[0092] In addition, in the first variation, the maximum first ratio, i.e., the ratio of the maximum first distance p1max to the maximum second distance p2max, is between 0.8 and 1.2, and the minimum first ratio, i.e., the ratio of the minimum first distance p1min to the minimum second distance p2min, is between 0.8 and 1.2.

[0093] According to these structures, the heat and stress applied from the main body 211 to the side walls 31 of the housing 3 can be dispersed more evenly.

[0094] In addition, in the above-described embodiment and the above-described first modification, the R surfaces are formed at the four corners of the main body portion 211 .

[0095] According to this configuration, it is easy to wind the resistance wire 24 around the outer peripheral surface of the main body 211 .

[0096] In addition, in the above-mentioned embodiment, a pair of side planes 211a, 211b are respectively arranged parallel to a pair of inner planes 311a, 311b, and the ratio of the first distance p1 to the second distance p2, that is, the first ratio, is between 0.8 and 1.2. The first distance p1 is the distance between the side plane 211a on one side and the inner plane 311a of the side wall 31a on one side, and the second distance p2 is the distance between the side plane 211b on the other side and the inner plane 311b of the side wall 31b on the other side.

[0097] According to this configuration, the stress applied from the main body 211 to the side walls 31 of the housing 3 can be evenly dispersed.

[0098] In addition, in the above-mentioned embodiment, the resistor 21 is accommodated in the accommodating space S in such a manner that the bottom plane 211d of the main body 211 and the inner plane 331 of the bottom wall 33 are parallel to each other, and the ratio of the first distance p1 to the third distance p3, that is, the second ratio, is between 0.8 and 1.2, and the ratio of the second distance p2 to the third distance p3, that is, the third ratio, is between 0.8 and 1.2, and the third distance p3 is the distance between the bottom plane 211d and the inner plane 331 of the bottom wall 33.

[0099] According to this configuration, since the distance between the bottom plane 211d of the main body 211 and the inner plane 331 of the bottom wall 33 can be made uniform, the stress applied from the main body 211 to the bottom wall 33 of the housing 3 can be dispersed compared to the case where the cylindrical main body is accommodated in the housing 3. In addition, the stress applied from the main body 211 to the walls 31 and 33 of the housing 3 can be evenly dispersed.

[0100] In addition, in the above-mentioned embodiment, the mounting portion 22 has a welding area 222 that protrudes outward further than the side plane 211a on one side of the main body 211 when mounted on the mounted portion 212, and the resistor element 2 also has a resistor wire 24 wound around the outer peripheral surface of the main body 211 in a manner such that the end 241 is fixed to the welding area 222 by welding.

[0101] According to this configuration, when the resistance wire 24 is wound from the weldable area 222 (i.e., a high position / outer position) to the outer peripheral surface of the main body 211 (i.e., a low position / inner position), the load in the peeling direction at the welding point formed by welding the end 241 and the weldable area 222 can be reduced.

[0102] In the modified example, the mounted portion 212 is configured in a rectangular column shape similar to the main body portion 211 .

[0103] According to this configuration, compared with a case where a cylindrical mounted portion is accommodated in the case 3 , it is possible to disperse stress applied from the mounted portion 212 to the case 3 .

[0104] In the above embodiment, the mounted portion 212 is located inside the main body 211 in cross-sectional view, and the ratio of the cross-sectional area of ​​the mounted portion 212 to the cross-sectional area of ​​the main body 211 is 0.8 or more.

[0105] According to this configuration, the difference in stress on the housing 3 caused by the difference in shape between the main body portion 211 and the attached portion 212 can be suppressed to be small.

[0106] As mentioned above, although this embodiment was described, the said embodiment only shows a part of application examples of this invention, and it is not intended that the technical scope of this invention is limited to the specific structure of the said embodiment.

Claims

1. A resistor comprising a resistor element and a box-shaped housing, The resistance element has: The resistor has a prism-shaped main body having a pair of side surfaces facing each other and a pair of mounted portions located at both ends of the main body. a pair of mounting parts, respectively mounted on the pair of mounted parts; and A pair of terminal plates are respectively arranged on the mounted portion through a pair of the mounting portions, The box-shaped housing comprises a pair of side walls extending in the height direction when viewed in cross section, an opening formed at one end of the pair of side walls, a bottom wall extending in the width direction when viewed in cross section at the other end of the pair of side walls, and a storage space surrounded by the pair of side walls and the bottom wall to store the resistor. The resistor is accommodated in the accommodation space via a sealing material so that the pair of side surfaces are opposed to the inner side surfaces of the pair of side walls, respectively.

2. The resistor according to claim 1, wherein The prism shape is composed of square columns, The pair of side surfaces are respectively constituted by a pair of curved surfaces protruding toward the inner side surfaces of the pair of side walls. When viewed in cross section, a pair of imaginary straight lines connecting the two ends of the pair of curved surfaces extend in the height direction. The ratio of the maximum first distance to the minimum first distance is greater than 1.0 and less than 2.5, the maximum first distance being the distance between one end of the curved surface located closer to the opening side than the bottom wall and one of the inner side surfaces, and the minimum first distance being the distance between the vertex of the curved surface and one of the inner side surfaces, The ratio of the maximum second distance to the minimum second distance is greater than 1.0 and less than 2.5, the maximum second distance being the distance between an end of the other curved surface located closer to the opening side than the bottom wall side and the other inner side surface, and the minimum second distance being the distance between the vertex of the other curved surface and the other inner side surface.

3. The resistor according to claim 2, wherein The ratio of the maximum first distance to the maximum second distance, i.e., the maximum first ratio, is between 0.8 and 1.

2. A ratio of the minimum first distance to the minimum second distance, ie, a minimum first ratio, is between 0.8 and 1.

2.

4. The resistor according to claim 2, wherein Rounded surfaces are formed at four corners of the main body.

5. The resistor according to claim 1, wherein The pair of side surfaces are respectively opposed to the pair of inner side surfaces in parallel, A first ratio, i.e., a ratio of a first distance between one of the side surfaces and an inner side surface of one of the side walls, and a first ratio between a second distance between another of the side surfaces and an inner side surface of another of the side walls, is between 0.8 and 1.

2.

6. The resistor according to claim 5, wherein The resistor is accommodated in the accommodation space in such a manner that the bottom plane of the main body and the inner plane of the bottom wall are parallel and opposite to each other. The ratio of the first distance to the third distance, i.e., the second ratio, is between 0.8 and 1.2, and the third distance is the distance between the bottom plane and the inner side plane of the bottom wall. A third ratio, that is, a ratio of the second distance to the third distance, is between 0.8 and 1.

2.

7. The resistor according to claim 5, wherein The prism shape is composed of square columns, Rounded surfaces are formed at four corners of the main body.

8. The resistor according to claim 1, wherein The mounting portion has a weldable region protruding outwardly from the side surface of the main body portion when the mounting portion is mounted on the mounted portion. The resistance element further includes a resistance wire wound around the outer peripheral surface of the main body portion so that an end portion thereof is fixed to the weldable region by welding.

9. The resistor according to claim 8, wherein A step is formed between the main body and the mounted portion, which is formed by an end surface of the main body exposed from the mounted portion. The minimum height of the step is greater than 1 / 3 of the thickness of the peripheral wall of the mounting portion and is smaller than the thickness of the peripheral wall.

10. The resistor according to claim 1, wherein The mounted portion is configured in a prismatic shape similar to the main body portion.

11. The resistor according to claim 1, wherein The mounted portion is located inside the main body when viewed in cross section. A ratio of an area of ​​a cross section of the mounted portion to an area of ​​a cross section of the main body portion is greater than or equal to 0.8.

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