Connectors

Abstract

A connector is provided that can stably hold a terminal part in a housing. The connector (10) includes a housing (20) and a terminal part (50) held in the housing (20). The housing (20) includes: holes (30) arranged in a plurality in the left-right direction, with the terminal part (50) arranged inside; an upper wall (28) and a lower wall (29) forming upper and lower areas of the plurality of holes (30) arranged in the left-right direction on the rear surface of the housing (20); and an interpole wall (33) that separates the holes (30) adjacent to each other in the left-right direction. The rear surface (33A) of the interpole wall (33) is located forward of the upper wall (28) and the lower wall (29). The housing (20) has a recess (34) having the rear surface (33A) of the interpole wall (33) as the bottom surface.

Description

Technical Field

[0001] The present disclosure relates to connectors. Background Art

[0002] The substrate connector disclosed in Patent Document 1 includes a housing and a plurality of terminal components mounted on the housing. The housing is formed with a mating recess for mating with a mating housing. The inner wall of the mating recess is provided with a plurality of press-in holes for press-in of the terminal components. The plurality of press-in holes are arranged in two layers, one above the other, along the width. The wall separating adjacent press-in holes (inter-electrode wall) forms part of the rear surface of the housing and is exposed at the rear.

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Laid-Open No. 2006-100231 Summary of the Invention

[0006] Problems to be solved by the invention

[0007] In a substrate connector configuration such as that described in Patent Document 1, where the housing has exposed interpole walls between multiple press-fit holes, foreign matter can sometimes come into contact with the rear surface of the interpole walls. This contact can affect the housing's ability to hold the terminal components. Therefore, a configuration is required that can stably hold the terminal components.

[0008] Therefore, the present invention has been made based on the above circumstances, and an object of the present invention is to provide a connector capable of stably holding terminal parts in a housing.

[0009] Solutions to Problems

[0010] The connector disclosed herein comprises: a shell; and terminal parts, which are held in the shell, and the shell comprises: holes, which are arranged in a plurality in the left-right direction, and the terminal parts are arranged on the inner side; an upper wall and a lower wall, which constitute upper and lower areas of the plurality of holes arranged in the left-right direction on the rear surface of the shell; and an interpole wall, which separates the holes adjacent to each other in the left-right direction, the rear surface of the interpole wall is located in front of the upper wall and the lower wall, and the shell has a recessed portion with the rear surface of the interpole wall as the bottom surface.

[0011] Effects of the Invention

[0012] According to the present disclosure, it is possible to provide a connector capable of stably holding terminal parts in a housing. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 This is a perspective view of the connector of Example 1.

[0014] Figure 2 is the rear view of the connector.

[0015] Figure 3 It is enlarged to show Figure 2 The hole and the enlarged view of its vicinity.

[0016] Figure 4 yes Figure 2 AA cross-sectional view.

[0017] Figure 5 It is enlarged to show Figure 4 The hole and the enlarged view of its vicinity.

[0018] Figure 6 yes Figure 4 BB cross-sectional view.

[0019] Figure 7 yes Figure 2 CC cross-sectional view.

[0020] Figure 8 yes Figure 4 DD cross-sectional view.

[0021] Figure 9 yes Figure 2 EE cross-sectional view.

[0022] Figure 10 This is a three-dimensional view of the terminal parts.

[0023] Figure 11 This is a top view of the terminal parts. DETAILED DESCRIPTION

[0024] [Description of Embodiments of the Present Disclosure]

[0025] First, embodiments of the present disclosure will be described below.

[0026] The connector disclosed in the present invention (1) comprises: a shell; and a terminal part, which is held in the shell, the shell comprising: holes, the holes being arranged in a plurality in the left-right direction, and the terminal part being arranged on the inner side; an upper wall and a lower wall, the upper wall and the lower wall constituting upper and lower areas of the plurality of holes arranged in the left-right direction on the rear surface of the shell; and an interpole wall, which separates the holes adjacent to each other in the left-right direction, the rear surface of the interpole wall being located forward of the upper wall and the lower wall, and the shell having a recess with the rear surface of the interpole wall as the bottom surface.

[0027] In the housing, the rear surface of the interelectrode wall between adjacent holes forms the bottom of the recess and is positioned forward of the upper and lower walls. Therefore, foreign matter is shielded by the upper and lower walls and is unlikely to directly contact the recess. As a result, the housing can stably hold the terminal components.

[0028] (2) Preferably, a rib extending continuously in the left-right direction is protruded from the rear surface of the housing, rear portions of the plurality of holes are provided inside the rib, and the upper wall surface and the lower wall surface are provided on the rear surface of the rib.

[0029] According to this structure, the rigidity of the housing in the left-right direction is increased by the ribs, and the housing is less likely to warp. As a result, the arrangement and shape of the recess, the upper wall surface, and the lower wall surface can be maintained.

[0030] (3) Preferably, the hole has a stepped opening, which expands to the left and right sides from the hole body extending in the front-to-back direction and opens on the rear surface of the inter-electrode wall. The terminal part has a protrusion protruding to the left and right sides in the middle part in the front-to-back direction. The protrusion is arranged in the stepped opening in an engaged state with the stepped opening and has a portion protruding rearward from the stepped opening.

[0031] According to this structure, the jig abuts against the rear surface of the protrusion, and the terminal component can be inserted into the hole of the housing from the rear. At this time, since the rear end of the protrusion protrudes rearward than the stepped opening, contact between the jig and the inter-electrode wall can be avoided.

[0032] (4) Preferably, among the protruding portions protruding to the left and right sides, the left-right dimension of the rear end of one of the protruding portions is larger than the left-right dimension of the rear end of the other protruding portion.

[0033] According to this structure, the jig can be brought into contact with the rear end of one protruding portion over a wider area, and the possibility of the jig falling off the protruding portion can be reduced.

[0034] (5) Preferably, the rear surface of the shell has side wall surfaces at both ends in the left and right directions, and the side wall surfaces constitute the left area of ​​the hole on the left side and the right area of ​​the hole on the right side of the holes arranged at both ends in the left and right directions, and the side wall surfaces are located behind the rear surface of the interpolar wall.

[0035] According to this structure, the holes arranged at both ends in the left and right directions do not have the rear surface of the inter-electrode wall (the bottom surface of the recess) provided on the left and right sides, but are provided with side walls. Therefore, the housing can improve the strength of the holes arranged at both ends in the left and right directions, and can stably hold the terminal parts in the holes.

[0036] [Details of the embodiments of the present disclosure]

[0037] [Example 1]

[0038] Reference Figures 1 to 11 A description will be given of a first embodiment of the connector of the present disclosure. Figure 1 The connector 10 of the present embodiment 1 is a substrate connector. Figure 9 As shown, it is provided on the board surface (surface) of the circuit board 70. The connector 10 comprises: a housing 20; terminal parts 50, 90; and a fixing member 60. Figure 9 As shown, the housing 20 can be engaged with the counterpart housing 80 .

[0039] <Housing>

[0040] Figure 1 、 Figure 2 The shell 20 shown is made of synthetic resin. The shell 20 has a square cylindrical cover portion 21 that is open at the front. The cover portion 21 has a back wall 22 in the up-down direction, and a fitting portion 23 that protrudes forward from the outer edge of the back wall 22. The front-to-back direction is the direction along which the shell 20 is assembled to the other shell 80. In addition, "front" is the direction from the back wall 22 toward the top of the fitting portion 23 in the front-to-back direction. "Rear" is the direction opposite to "front" in the front-to-back direction, and is the direction from the top of the fitting portion 23 toward the back wall 22. In Figure 1 , 2, 4, the front-back direction is shown as the X direction. Figure 1 In , 2, and 7, the "front" is shown as the +X direction and the "rear" is shown as the -X direction.

[0041] like Figure 1 As shown, the back wall 22 is provided with a pair of protective walls 24 protruding rearward at both ends in the left and right directions. The fitting portion 23 has a pair of side walls 23A, which are arranged in a manner of standing upright from the board surface of the circuit board 70. The outer surfaces of the side walls 23A are formed flat (vertically) in the vertical direction. Figure 9 As shown, a locking portion 23B is provided on the inner side of the front end of the fitting portion 23 , and the locking portion 23B is locked with the locking arm 82 of the counterpart housing 80 .

[0042] like Figure 2 As shown, the back wall 22 is provided with upper ribs 25 and lower ribs 26 that protrude rearward in two layers. The upper ribs 25 and lower ribs 26 extend continuously in the left-right direction. The rear portion of the hole 30 described below is provided inside the upper ribs 25 and lower ribs 26.

[0043] The left-right direction is a direction that intersects the front-back direction and is along the width direction of the terminal parts 50, 90. "Left" is one direction in the left-right direction, and is the left direction when the connector 10 is viewed from the front to the back, with the connector 10 set to a posture that is consistent with the gravity direction in a predetermined reference direction (the +Z direction described later). "Right" is the direction opposite to the left direction in the left-right direction. The up-down direction is a direction that intersects the front-back direction and the left-right direction. Figure 1 , 2, 7, the left and right directions are shown as the Y direction. Figure 1 , 2, 7, "left" is shown as the +Y direction, and "right" is shown as the -Y direction. Figure 1 , 2, 7, the up and down direction is shown as the Z direction. Figure 1 , 2, and 7, "up" is shown as the +Z direction and "down" is shown as the -Z direction. In the present embodiment, the left-right direction intersects the front-back direction perpendicularly. In addition, perpendicularly intersecting includes a state of intersecting approximately perpendicularly in addition to a state of strictly intersecting perpendicularly. Approximately perpendicular means that in the present embodiment, the angle formed by one direction and another direction is greater than 80 degrees and less than 90 degrees, preferably greater than 85 degrees and less than 90 degrees, and more preferably greater than 88 degrees and less than 90 degrees. Along the direction means that in the present embodiment, one direction is parallel or approximately parallel to another direction. Approximately parallel means that in the present embodiment, the angle formed by one direction and another direction is greater than 170 degrees and less than 180 degrees, preferably greater than 175 degrees and less than 180 degrees, and more preferably greater than 178 degrees and less than 180 degrees.

[0044] The rear surface of the housing 20 (the rear surface of the upper rib 25) is provided with an upper wall surface 28 and a lower wall surface 29 (see FIG. 2 ) which constitute upper and lower regions of a hole 30 described later. Figure 7 ) In addition, the lower rib 26 is also provided with a wall surface similar to the upper wall surface 28 and the lower wall surface 29 of the upper rib 25 .

[0045] like Figure 4 、 Figure 5 As shown, a plurality of holes 30 are provided in the back wall 22 extending through the front and back, and a terminal part 50 is arranged on the inner side of each hole 30. The terminal part 50 is pressed into each hole 30 of the back wall 22 and retained. A plurality of holes 30 are arranged in the left and right directions in two layers. The following describes the holes 30 in the upper layer, but the holes 30 in the lower layer also have the same structure. Specifically, the structure of the holes 30 in the lower layer is the structure of the holes 30 in the upper layer reversed left and right. As shown Figure 2 、 Figure 7As shown, the rear portion of each hole 30 in the upper layer is arranged on the inner side of the upper rib 25. The hole 30 has a hole body 31 and a stepped opening 32. The hole body 31 is arranged on the front end side of the back wall 22. In the hole body 31, the other connection portion 51 of the terminal part 50 described later is pressed from the rear. The other connection portion 51 is maintained in a non-detachment state in the hole body 31 by the locking action of the locking piece 55. The stepped opening 32 is provided on the rear end side of the back wall 22. The stepped opening 32 expands from the hole body 31 extending in the front-to-back direction to the left and right sides, and opens at the rear surface 33A of the inter-electrode wall 33. In the stepped opening 32, the protrusions 53A and 53B of the terminal part 50 described later are arranged in a fitted state. The stepped opening 32 is connected to the upper wall surface 28 and the lower wall surface 29 in the up-down direction. The length of the stepped opening 32 in the vertical direction is approximately the same as the thickness of the intermediate portion 53 of the terminal part 50 described later in the vertical direction. Figure 6 、 Figure 7 As shown, an introduction portion 32A that expands rearward in a tapered shape is provided at the rear end of the stepped opening 32 .

[0046] like Figure 5 As shown, the housing 20 is provided with an interpole wall 33 that separates adjacent holes 30. A rear surface 33A of the interpole wall 33 is located forward of the upper wall 28 and the lower wall 29. The housing 20 has a recess 34 with the rear surface 33A of the interpole wall 33 as the bottom surface.

[0047] like Figure 2 、 Figure 4 As shown, the rear surface of the housing 20 has sidewall surfaces 22B at both ends in the left-right direction. The sidewall surfaces 22B constitute the left region of the left hole 30 and the right region of the right hole 30 of the holes 30 arranged at both ends in the left-right direction, and are located rearward of the rear surface 33A of the inter-electrode wall 33. The left opening of the hole 30 arranged at the left end refers to the left edge of the rear opening of the hole 30. The right opening of the hole 30 arranged at the right end refers to the right edge of the rear opening of the hole 30. The left and right sidewall surfaces 22B are connected to the upper wall surface 28 and the lower wall surface 29 in the vertical direction.

[0048] like Figure 8As shown, the outer surfaces of the two side walls 23A of the fitting portion 23 are recessed with an assembly surface 40. The assembly surface 40 is arranged in the up-down direction and the left-right direction. The two side walls 23A have front and rear receiving portions 41 on the front and rear sides of the assembly surface 40. The receiving portion 41 receives the locking portion 63 of the fixing member 60 described later. The following description focuses on the front receiving portion 41, but the rear receiving portion 41 also has the same structure. The receiving portion 41 has an upper groove portion 42, a lower groove portion 43, side ribs 44, and an extension portion 45. The upper groove portion 42 constitutes the upper end portion of the receiving portion 41 and is a groove recessed toward the front. The upper groove portion 42 locks the upper protrusion 64 of the fixing member 60 described later. The lower groove portion 43 constitutes the lower end portion of the receiving portion 41 and is a groove recessed toward the front. The lower groove portion 43 locks the lower protrusion 65 of the fixing member 60 described later. The side ribs 44 are provided in the receiving portion 41 between the upper groove 42 and the lower groove 43. The side ribs 44 are vertically elongated protrusions that protrude rearward. The upper ends of the side ribs 44 are inclined downward and rearward. The side ribs 44 contact the bent portion 66 of the fixing member 60, described later. The extension 45 is provided in the receiving portion 41 below the lower groove 43. The extension 45 is a wall that protrudes rearward. The protrusion 67 of the fixing member 60, described later, contacts the extension 45.

[0049] <Terminal parts>

[0050] The following describes the terminal part 50 held in the hole 30 of the upper layer, but the terminal part 90 held in the hole 30 of the lower layer also has the same structure. Specifically, the terminal part 90 is formed to be reversed left and right relative to the terminal part 50. The length dimension of the terminal part 90 is smaller than that of the terminal part 50. Figure 10 、 Figure 11 As shown, the terminal part 50 is formed into a pin shape with a rectangular cross section. The terminal part 50 is formed into a crank shape by bending at right angles at two locations in the middle of the length direction of the terminal base material. Specifically, the terminal part 50 has a counterpart connection portion 51, a substrate connection portion 52, an intermediate portion 53, and a bent portion 54. Figure 9 As shown, when the housing 20 is mated with the mating housing 80, the mating connection portion 51 is electrically connected to the mating terminal fitting 81 held in the mating housing 80. The mating connection portion 51 has claw-shaped locking tabs 55 projecting in both directions at multiple locations near the rear end. The locking tabs 55 bite into the inner surface of the hole body 31 of the housing 20 to lock.

[0051] The substrate connection portion 52 extends downward from the bent portion 54 and is bent rearward. The distal end of the substrate connection portion 52 is arranged along the surface of the circuit board 70 and is electrically connected to a conductive portion (not shown) of the circuit board 70 by soldering.

[0052] The middle portion 53 is located between the other connection portion 51 and the substrate connection portion 52 (more specifically, the bent portion 54). The middle portion 53 has protrusions 53A and 53B that protrude to the left and right sides. Figure 5 As shown, the protrusions 53A and 53B are arranged in the stepped opening 32 in a state of being fitted with the stepped opening 32, and have a portion (rear end) that protrudes rearward from the stepped opening 32. The front-to-back dimensions of the protrusions 53A and 53B are larger than the front-to-back dimensions of the stepped opening 32. The left-to-right dimension of the rear end of the protrusion 53B is larger than the left-to-right dimension of the rear end of the protrusion 53A.

[0053] <Fixed components>

[0054] The fixing member 60 is made of metal and is formed into a flat plate shape as a whole. Figure 1 、 Figure 4 As shown, two fixing members 60 are assembled on the cover portion 21 so as to correspond to each of the two side walls 23A of the housing 20 .

[0055] like Figure 1 As shown, the fixing member 60 has a housing fixing portion 61 fixed to the housing 20 and a substrate fixing portion 62 fixed to the circuit board 70. The housing fixing portion 61 is a flat plate in the up-down direction. A locking portion 63 is provided on both sides of the housing fixing portion 61 in the front-back direction (board width direction). The locking portion 63 enters the corresponding receiving portion 41 in the front and back and is received. Figure 8 ) is described, but the locking portion 63 on the rear side also has the same structure. The locking portion 63 has an upper protruding portion 64, a lower protruding portion 65, a bent portion 66, and a protrusion 67. The upper protruding portion 64 constitutes the upper end of the locking portion 63 and protrudes toward the front. The lower protruding portion 65 constitutes the central part of the locking portion 63 in the up and down directions and protrudes toward the front. The bent portion 66 is provided between the upper protruding portion 64 and the lower protruding portion 65 in the locking portion 63. The bent portion 66 is a plate piece that is bent at a right angle relative to the plate surface of the shell fixing portion 61. The protrusion 67 is provided on the lower side of the lower protruding portion 65 in the locking portion 63. The protrusion 67 protrudes forward along the plate surface of the shell fixing portion 61.

[0056] As described above, in the connector 10 of the present disclosure, in the housing 20, the rear surface 33A of the inter-electrode wall 33 located between adjacent holes 30 serves as the bottom surface of the recess 34 and is located forward of the upper wall 28 and the lower wall 29. Therefore, foreign matter is shielded by the upper wall 28 and the lower wall 29 and is unlikely to directly contact the recess 34. Consequently, the housing 20 can stably hold the terminal fitting 50.

[0057] An upper rib 25 and a lower rib 26 protrude from the rear surface of the housing 20. The upper and lower ribs 25 and 26 extend continuously in the horizontal direction. The rear portions of the plurality of holes 30 are located inside the upper and lower ribs 25 and 26, and the upper and lower wall surfaces 28 and 29 are located on the rear surfaces of the upper and lower ribs 25 and 26. Thus, the upper and lower ribs 25 and 26 enhance the horizontal rigidity of the housing 20, making it less susceptible to warping. As a result, the arrangement and shape of the recessed portion 34, the upper and lower wall surfaces 28, and the lower wall surfaces 29 are maintained.

[0058] The hole 30 has a stepped opening 32 that expands leftward and rightward from a main hole body 31 extending in the front-to-back direction, opening at the rear surface 33A of the inter-electrode wall 33. The terminal fitting 50 has protrusions 53A and 53B protruding leftward and rightward at its intermediate portion 53 in the front-to-back direction. These protrusions 53A and 53B are positioned within the stepped opening 32 to engage with the protrusions 53A and 53B, and have portions that protrude rearward from the stepped opening 32. Thus, the terminal fitting 50 can be inserted from the rear into the hole 30 of the housing 20 by contacting a jig with the rear surfaces of the protrusions 53A and 53B. At this time, since the rear ends of the protrusions 53A and 53B protrude rearward of the stepped opening 32, contact between the jig and the inter-electrode wall 33 is avoided.

[0059] Of the protruding portions 53A and 53B that protrude to the left and right sides, the left-right dimension of the rear end of protruding portion 53B is larger than the left-right dimension of the rear end of protruding portion 53A. This allows the jig to abut against the rear end of protruding portion 53B over a wider area, reducing the risk of the jig falling off protruding portion 53B.

[0060] The rear surface of the housing 20 has sidewall surfaces 22B at both ends in the left-right direction. These sidewall surfaces 22B define the left region of the left hole 30 and the right region of the right hole 30, respectively, and are located rearward of the rear surface 33A of the inter-pole wall 33 (the bottom surface of the recess 34). Consequently, the holes 30 at both ends in the left-right direction are not provided with the rear surface 33A of the inter-pole wall 33, but are provided with sidewall surfaces 22B on their respective left and right sides. This improves the strength of the holes 30 at both ends in the left-right direction, allowing the terminal fitting 50 to be stably retained in the holes 30.

[0061] [Other embodiments of the present disclosure]

[0062] The embodiments disclosed herein are to be considered in all respects as illustrative and non-restrictive. For example, the following embodiments can be employed.

[0063] (1) In the above-mentioned first embodiment, a configuration is exemplified in which the plurality of holes 30 are provided in two layers, upper and lower, of the housing 20. However, the plurality of holes 30 may be provided in one layer or in three or more layers.

[0064] (2) In the first embodiment, the left-right dimension of the rear end of the protrusion 53B is larger than that of the rear end of the protrusion 53A. However, the opposite size relationship may be adopted, or the sizes may be similar.

[0065] (3) In the first embodiment, the terminal fitting 50 is press-fitted into the hole 30 of the housing 20 and retained. However, it may be insert-molded into the housing 20 .

[0066] Description of Reference Numerals

[0067] 10…Connector

[0068] 20…housing

[0069] 21…hood

[0070] 22…Back wall

[0071] 22B…Side wall

[0072] 23…Chimeric part

[0073] 23A…Sidewall

[0074] 23B…locking part

[0075] 24…Protective wall

[0076] 25…upper ribs (ribs)

[0077] 26…lower ribs (ribs)

[0078] 28…Upper wall

[0079] 29…lower wall

[0080] 30…holes

[0081] 31…Hole body

[0082] 32…Stepped opening

[0083] 32A…Introduction

[0084] 33…Interpolar wall

[0085] 33A… rear surface of the interelectrode wall

[0086] 34…concave

[0087] 40…Assembly surface

[0088] 41…Receiving Department

[0089] 42…Upper groove

[0090] 43…lower groove part

[0091] 44…Side ribs

[0092] 45…Extension

[0093] 50…Terminal parts

[0094] 51…Other connection part

[0095] 52…Substrate connection part

[0096] 53…Middle

[0097] 53A, 53B…protrusion

[0098] 54…Bend

[0099] 55…Locking piece

[0100] 60…Fixed components

[0101] 61…Casing fixing portion

[0102] 62...Substrate fixing part

[0103] 63…Locking part

[0104] 64…Upper protrusion

[0105] 65…lower side protrusion

[0106] 66…Bending section

[0107] 67…Protrusion

[0108] 70...circuit board

[0109] 80…Other shell

[0110] 81…Mating terminal parts

[0111] 82…Arm Lock

[0112] 90…Terminal parts

Claims

1. A connector comprising: housing; and a terminal part held in the housing, wherein The housing comprises: a hole, the hole being arranged in a plurality in the left-right direction and having the terminal part arranged inside; an upper wall surface and a lower wall surface, the upper wall surface and the lower wall surface forming upper and lower areas of a plurality of the holes arranged in the left-right direction on the rear surface of the housing; and an interpolar wall that separates the holes adjacent to each other in the left-right direction, wherein The rear surface of the inter-electrode wall is located in front of the upper wall surface and the lower wall surface. The housing has a recessed portion with the rear surface of the inter-electrode wall as a bottom surface. The upper and lower widths of the hole correspond to the thickness of the terminal part in the upper and lower directions, and the upper and lower edges of the hole are connected to the upper and lower edges of the rear surface of the inter-electrode wall without steps in the left-right direction.

2. The connector according to claim 1, wherein A rib extending continuously in the left-right direction is protruded from the rear surface of the housing, rear portions of the plurality of holes are provided inside the rib, and the upper wall surface and the lower wall surface are provided on the rear surface of the rib.

3. The connector according to claim 1 or claim 2, wherein: The hole has a stepped opening that expands toward both left and right sides from a hole main body extending in the front-rear direction and opens at the rear surface of the interpolar wall. The terminal part has a protrusion protruding to the left and right sides in the middle part in the front-back direction. The protrusion is arranged in the stepped opening in a state of being fitted with the stepped opening, and has a portion protruding rearward from the stepped opening.

4. The connector according to claim 3, wherein Of the protruding portions protruding to the left and right sides, the left-right dimension of the rear end of one of the protruding portions is larger than the left-right dimension of the rear end of the other protruding portion.

5. The connector according to claim 1 or claim 2, wherein: The rear surface of the housing has side wall surfaces at both ends in the left and right directions. The side wall surface constitutes a left region of the hole on the left side and a right region of the hole on the right side of the holes arranged at both ends in the left-right direction, and is located rearward of a rear surface of the inter-electrode wall.

Images