JP6222039B2 - Female terminal - Google Patents

Description

  The technique disclosed by this specification is related with the female terminal connected to a male terminal.

  2. Description of the Related Art Conventionally, as female terminal fittings connected to a counterpart terminal, for example, those described in Japanese Utility Model Publication No. 6-9069 (Patent Document 1 below) are known. The female terminal fitting is configured to include a box-shaped electrical contact portion including a substrate, a side wall, and an upper plate, and an elastic contact piece disposed inside the electrical contact portion. The elastic contact piece is formed in a cantilever shape by folding back from the front edge of the substrate. Further, the elastic contact piece has a mountain shape when viewed from the side, and is in line contact with the counterpart terminal at the apex portion of the mountain shape.

  However, in the female terminal fitting described above, when at least one of the counterpart terminal and the female terminal fixture is relatively twisted around the insertion direction of the counterpart terminal into the electrical contact portion, the contact between the elastic contact piece and the counterpart terminal The state changes from line contact to point contact, and the contact area changes rapidly. Then, like the female terminal metal fitting described in Japanese Patent Laid-Open No. 8-250174 (Patent Document 2 below), the contact portion of the elastic contact piece with the mating terminal is embossed so that the contact area at the time of twisting can be reduced. A method of eliminating sudden changes is also conceivable.

Japanese Utility Model Publication No. 6-9069 JP-A-8-250174

  However, according to this method, the tip of the counterpart terminal hits the contact part from the front, and excessive stress is applied to the plating applied to the surface of the contact part. May occur.

  The female terminal disclosed in the present specification is formed in a cylindrical shape by a plurality of peripheral walls, and a male terminal is fitted from the front, and the male terminal is elastically brought into contact with the male terminal. An elastic piece that extends rearward from the peripheral wall, the cross-sectional shape in the insertion direction of the male terminal is linear, and the cross-sectional shape in the direction orthogonal to the insertion direction is From a flat part that forms a straight line, a gradual change part that extends rearward from the rear end of the flat part, and the contact area with the male terminal gradually decreases toward the rear, and from the rear end of the gradual change part A cylindrical portion that extends rearward and has a linear cross-sectional shape in the insertion direction of the male terminal, and an arc-shaped cross-sectional shape in a direction orthogonal to the insertion direction, and rearward from the rear end of the cylindrical portion Extended in the insertion direction of the male terminal A contact portion whose surface shape is arcuate and whose cross-sectional shape in the direction orthogonal to the insertion direction is arcuate, and the flat portion, the gradually changing portion, and the male terminal in the cylindrical portion The contact surface is formed in a linearly continuous form when viewed from a direction orthogonal to the insertion direction, and the contact portion is arranged in a region not exceeding a surface that is flush with the contact surface with the male terminal in the cylindrical portion. It was set as the structure.

  According to such a configuration, the male terminal inserted into the fitting portion enters while sliding on the elastic piece and makes point contact at the apex of the contact portion. Here, since the contact area with the male terminal gradually decreases in the process in which the male terminal passes through the gradual change portion, the contact state between the elastic piece and the male terminal gradually changes from line contact or surface contact to point contact. During this time, in addition to the decrease in the contact area with the male terminal, the contact pressure increases as the amount of displacement of the elastic piece increases, so that the connection state is stabilized.

  In addition, since the contact surface with the male terminal in the flat portion, the gradual change portion, and the cylindrical portion is formed in a straight line when viewed from the direction orthogonal to the insertion direction, the tip of the male terminal hits the contact portion from the front. Thus, the stress applied to the contact portion does not increase. That is, when the male terminal moves from the gradually changing portion to the contact portion, the stress does not increase by climbing on the contact portion. Therefore, when plating is formed on the surface of the contact portion, even if repeated insertion / extraction is performed, plating wear can be suppressed and contact failure can be prevented.

The female terminal disclosed in this specification may have the following configuration.
The gradual change portion has a straight cross-sectional shape in the insertion direction of the male terminal, and a cross-section in a direction orthogonal to the insertion direction of the male terminal has an arc shape, and the male terminal in the gradual change portion and The contact surface may be configured to have a radius of curvature that increases toward the front and a length in the circumferential direction that increases toward the rear.
According to such a structure, a gradually changing part can be made by shape | molding the planar board | plate material connected back from a flat part in circular arc shape by press work. An example of this press working method will be specifically described. First, a plate material having an equal width is bent into a circular arc shape before being pressed. Then, the width dimension of the arc-shaped molded part increases as the curvature radius increases, and the width dimension decreases as the curvature radius decreases. Next, the outer peripheral punching process is performed to finish the arc-shaped formed portion to have the same width, and the gradually changing portion is formed. Then, the gradually changing portion has a shorter length in the circumferential direction as the radius of curvature is larger (as it goes forward), and a length in the circumferential direction is longer as the radius of curvature is smaller (as it goes backward).

The contact portion may have a spherical shape, and the radius of curvature in the insertion direction of the male terminal may be the same as the radius of curvature in the direction orthogonal to the insertion direction.
According to such a configuration, in forming the contact portion into a spherical shape, it is better to provide the contact portion immediately after the cylindrical portion having a simple shape than to provide the contact portion immediately after the gradually changing portion having a complicated shape. It is easy to mold, and it becomes easy to manage the dimensions near the contact point quantitatively. As an example of such dimensional management, for example, the clearance between the apex of the contact portion that makes point contact with the male terminal and the opposing portion that faces this can be managed. Further, the merit of making the contact portion spherical is that the position in contact with the male terminal is fixed at one point, and the clearance can be inspected by image inspection, and the inspection becomes easy.

  According to the technology disclosed in this specification, it is possible to prevent the stress from increasing due to the male terminal riding on the contact portion.

The perspective view which shows the female terminal in embodiment Top view of female terminal It is AA sectional view taken on the line in FIG. 2, Comprising: Sectional drawing which showed the state which the male terminal contacted the gradual change part Sectional drawing which showed the state which the male terminal further approached from the state of FIG. 3, and contacted the contact part Side view of female terminal BB sectional view in FIG. Sectional drawing which cut | disconnected the position which crosses the front-back direction center part of a flat part in the width direction Sectional drawing which cut | disconnected the position which crosses the front-back direction center part of a gradually changing part in the width direction Sectional view cut at a position crossing the central part in the front-rear direction of the cylindrical part in the width direction Sectional view cut at a position crossing the apex of the contact portion in the width direction Perspective view showing elastic piece

<Embodiment>
The embodiment will be described with reference to the drawings of FIGS. The female terminal 10 in this embodiment is electrically connected to the male terminal 1 as shown in FIGS. In the following description, the left side in FIG. 2 is the front side, and the right side in FIG. 2 is the back side. Further, the vertical direction is based on FIG.

  The male terminal 1 is obtained by pressing a metal plate material into a predetermined shape. As shown in FIG. 4, the male terminal 1 has a male tab 2 having an elongated plate shape, and the contact surface 3 of the male tab 2 with the female terminal 10 is a flat surface. Further, the tip portion of the contact surface 3 of the male tab 2 is configured as a tapered surface 4.

  As shown in FIG. 1, the female terminal 10 includes a fitting portion 20 into which the male terminal 1 is fitted from the front, and an elastic piece 30 that is arranged in the fitting portion 20 and elastically contacts the male terminal 1. The electric wire connecting portion 50 is disposed behind the fitting portion 20 and is electrically connected to the electric wire. The elastic piece 30 includes a plurality of first elastic pieces 31 and a plurality of second elastic pieces 32. Moreover, the electric wire connection part 50 comprises flat form, and the core wire of an electric wire is fixed by resistance welding.

  The fitting portion 20 has a substantially rectangular tube shape that opens in the front-rear direction. The male tab 2 of the male terminal 1 is inserted into the fitting portion 20 from the front. The fitting portion 20 has a plurality of peripheral walls configured in a rectangular tube shape. These peripheral walls include a bottom wall 21, a pair of side walls 22 rising upward from both side edges of the bottom wall 21, and the bottom wall 21. And a ceiling wall 23 opposed to each other.

  The ceiling wall 23 is formed by being bent at a substantially right angle from the upper end edge of the pair of side walls 22 toward the other side wall 22. A locking portion 24 protrudes from the edge of the ceiling wall 23, and this locking portion 24 is inserted into a locking hole 25 formed in the other side wall 22. The other side wall 22 is bent at a right angle at the height of the locking hole 25 and overlapped with the upper surface of the ceiling wall 23. Thereby, the fitting part 20 is hold | maintained at the rectangular tube shape.

  A first base end portion 26 protrudes from the front end edge of the bottom wall 21. The first base end portion 26 has a shape that is folded back (backward) from the front end edge of the bottom wall 21 to the inside of the fitting portion 20. As shown in FIG. 5, the first base end portion 26 slightly protrudes forward from the front end edge of the fitting portion 20.

  As shown in FIG. 6, the three first elastic pieces 31 shown in the figure lined up at intervals in the direction intersecting the insertion direction of the male terminal 1 at the end edge of the folded first base end portion 26. 20 extends inward (rearward). As shown in FIG. 5, the first elastic piece 31 extends from the first base end portion 26 in a cantilever shape in a straight line when viewed from the side. A first contact portion 33 is formed at the extended end portion of the first elastic piece 31, and the first contact portion 33 is in elastic contact with the male terminal 1. For example, silver plating is applied to the first contact portion 33. As shown in FIG. 15, the bottom wall 21 is provided with a first excessive deflection preventing portion 28 that prevents the first elastic piece 31 from being excessively bent and plastically deformed.

  As shown in FIG. 6, the length dimension of the front-back direction of each 1st elastic piece 31 is made the same. Moreover, the dimension of the width direction (direction orthogonal to the insertion direction of the male terminal 1) of each 1st elastic piece 31 is made the same. Further, the interval between the pair of adjacent first elastic pieces 31 is the same. Accordingly, the plurality of first elastic pieces 31 are arranged at equal intervals over substantially the entire width direction of the fitting portion 20.

  A second base end portion 27 protrudes from the front end edge of the ceiling wall 23. The second base end portion 27 has a shape that is folded back (backward) from the front end edge of the ceiling wall 23 to the inside of the fitting portion 20. As shown in FIG. 5, the second base end portion 27 slightly protrudes forward from the front end edge of the fitting portion 20. Since the second base end portion 27 has the same shape and size as the first base end portion 26, there are cases in which only the text is described without being shown.

  On the end edge of the folded second base end portion 27, three illustrated second elastic pieces 32 arranged at intervals in the direction intersecting the insertion direction of the male terminal 1 are located inwardly of the fitting portion 20 (rearward). To). As shown in FIG. 5, the second elastic piece 32 extends in a cantilevered manner from the second base end portion 27 when viewed from the side. A second contact portion 34 is formed at the extended end portion of the second elastic piece 32, and the second contact portion 34 elastically contacts the male terminal 1. For example, silver plating is applied to the second contact portion 34. As illustrated in FIG. 5, the ceiling wall 23 is provided with a second excessive deflection preventing portion 29 that prevents the second elastic piece 32 from being excessively bent and plastically deformed.

  Since the second elastic piece 32 has the same shape and size as the first elastic piece 31, there are cases where only the text will be described below without illustration. The length dimension in the front-rear direction of each second elastic piece 32 is the same. Moreover, the dimension of the width direction (direction orthogonal to the insertion direction of the male terminal 1) of each 2nd elastic piece 32 is made the same. Further, the interval between the pair of adjacent second elastic pieces 32 is the same. Accordingly, the plurality of second elastic pieces 32 are arranged at equal intervals over substantially the entire width direction of the fitting portion 20.

  The 1st base end part 26 and the 1st elastic piece 31, and the 2nd base end part 27 and the 2nd elastic piece 32 are formed vertically symmetrically. Thereby, the 1st contact part 33 of the 1st elastic piece 31 and the 2nd contact part 34 of the 2nd elastic piece 32 are each arranged facing the up-and-down direction.

  As shown in FIG. 11, the first elastic piece 31 includes a first flat portion 35 that extends rearward from the end edge of the first base end portion 26, and a rear portion of the first flat portion 35. A first gradually changing portion 37 extending rearward from the end 35R, a first cylindrical portion 39 extending rearward from a rear end 37R of the first gradually changing portion 37, and a rear of the first cylindrical portion 39 The first contact portion 33 extends rearward from the end 39R.

  Similarly, the second elastic piece 32 includes a second flat portion 36 that extends rearward from the end edge of the second base end portion 27 and a rear end 36R of the second flat portion 36. The second gradually changing portion 38 extended to the rear, the second cylindrical portion 40 extending rearward from the rear end 38R of the second gradually changing portion 38, and the rearward end 40R of the second cylindrical portion 40. And a second contact portion 34 extending in the direction.

  As shown in FIG. 7, the flat portions 35 and 36 have contact surfaces 35 </ b> A and 36 </ b> A with the male terminal 1 both in a flat shape (planar shape). The flat portions 35 and 36 have a straight cross-sectional shape in the insertion direction of the male terminal 1 and a cross-sectional shape in a direction orthogonal to the insertion direction. Accordingly, when the male terminal 1 is brought into contact with the flat portions 35 and 36 when fitted into the fitting portion 20, the male terminal 1 is brought into contact with the contact surfaces 35A and 36A of the flat portions 35 and 36 in a line contact or surface contact state. It will be in sliding contact.

  As shown in FIG. 8, the gradually changing portions 37 and 38 have a straight cross-sectional shape in the insertion direction of the male terminal 1, and a cross-section in a direction orthogonal to the insertion direction of the male terminal 1 has an arc shape. Yes. Further, the contact surfaces 37A, 38A of the gradually changing portions 37, 38 with the male terminal 1 have a radius of curvature that increases toward the front and a length in the circumferential direction that increases toward the rear. . That is, when the curvature radius on the front end side of the gradually changing portions 37 and 38 is R and the curvature radius on the rear end side is r, R> r. Similarly, C> c, where C is the circumferential length on the rear end side of the gradually changing portions 37 and 38 and c is the circumferential length on the front end side. According to the gradual change portions 37 and 38, the contact area with the male terminal 1 gradually decreases toward the rear, and the contact state with the male terminal 1 shifts from a line contact or surface contact state to a point contact state.

  Here, a method for forming the gradually changing portions 37 and 38 by press working will be briefly described. First, a planar plate material connected to the rear from the flat portions 35 and 36 is prepared so as to be wider than the flat portions 35 and 36. Next, the wide portion is bent and shaped so that the radius of curvature increases toward the front side of the wide portion. Then, the width dimension increases as the curvature radius increases, and the width dimension decreases as the curvature radius decreases. Next, an outer peripheral punching process is performed on the bent portion so as to finish the same width to obtain gradually changing portions 37 and 38. In this way, the greater the radius of curvature (the more forward it is), the shorter the length in the circumferential direction, and the smaller the radius of curvature (the more it goes back), the longer the length in the circumferential direction.

  As shown in FIG. 9, the cylindrical portions 39 and 40 have a straight cross-sectional shape in the insertion direction of the male terminal 1 and a circular cross-sectional shape in a direction orthogonal to the insertion direction. For this reason, the male terminal 1 is in sliding contact with the contact surfaces 39A, 40A of the cylindrical portions 39, 40 in a point contact state. Moreover, the contact surfaces 35A-40A with the male terminal 1 in the flat parts 35 and 36, the gradual change parts 37 and 38, and the cylindrical parts 39 and 40 are orthogonal to the insertion direction of the male terminal 1, as shown in FIG. When viewed from the direction, it is configured to be linear.

  The contact portions 33 and 34 have a spherical shape, and the curvature radius in the insertion direction of the male terminal 1 is the same as the curvature radius in the direction orthogonal to the insertion direction. Further, as shown in FIG. 5, the contact portions 33 and 34 are arranged in regions that do not exceed the surfaces 39B and 40B that are flush with the contact surfaces 39A and 40A of the cylindrical portions 39 and 40 with the male terminal 1. . Therefore, when the male terminal 1 is fitted to the fitting portion 20, the contact surface 3 of the male terminal 1 comes into contact with the contact surfaces 37 A and 38 A of the gradually changing portions 37 and 38 and starts sliding contact, and the cylindrical portion 39. , 40 slidably contact the contact surfaces 39A, 40A, then move to the contact portions 33, 34 without any step, and reach the vertices 33T, 34T while slidably contacting the contact surfaces 33A, 34A of the contact portions 33, 34. Therefore, it can suppress that the stress concerning each contact part 33 and 34 increases, and silver plating formed in the surface of each contact part 33 and 34 wears.

  When the male terminal 1 is twisted with the insertion direction of the male terminal 1 into the fitting portion 20 as an axis, the contact positions of the male terminal 1 and the contact portions 33 and 34 are determined from the vertices 33T and 34T. The contact state remains point contact, although it may be shifted clockwise or counterclockwise. That is, since the male terminal 1 maintains the point contact state with respect to the contact portions 33 and 34 before and after the twisting operation, the contact state between the male terminal 1 and the contact portions 33 and 34 is abrupt. The contact pressure is ensured at any contact location.

  As described above, in the present embodiment, the male terminal 1 inserted into the fitting portion 20 enters the elastic pieces 31 and 32 while being in sliding contact, and when the insertion is completed, at the vertices 33T and 34T of the contact portions 33 and 34. Point contact. Here, in the process in which the male terminal 1 passes through the gradual change portions 37 and 38, the contact area with the male terminal 1 gradually decreases, so that the contact state between the elastic pieces 31 and 32 and the male terminal 1 is line contact or surface contact. From point to point. During this time, in addition to the decrease in the contact area with the male terminal 1, the contact pressure increases as the amount of displacement of the elastic pieces 31, 32 increases, so the connection state is stabilized.

  Further, the contact surfaces 35A to 40A of the flat portions 35 and 36, the gradually changing portions 37 and 38, and the cylindrical portions 39 and 40 with the male terminal 1 are linearly connected when viewed from the direction orthogonal to the insertion direction. Thus, the stress applied to the contact portions 33 and 34 does not increase when the tip of the male terminal 1 hits the contact portions 33 and 34 from the front. That is, when the male terminal 1 moves from the gradual change portions 37 and 38 to the contact portions 33 and 34, the stress does not increase by riding on the contact portions 33 and 34. Therefore, when plating is formed on the surfaces of the contact portions 33 and 34, plating wear can be suppressed even if repeated insertion and removal is performed, and contact failure can be prevented.

The gradually changing portions 37 and 38 have a straight cross-sectional shape in the insertion direction of the male terminal 1 and a cross-section in a direction orthogonal to the insertion direction of the male terminal 1 in an arc shape. The contact surfaces 37A and 38A with the male terminal 1 may have a configuration in which the radius of curvature increases toward the front and the length in the circumferential direction increases toward the rear.
According to such a structure, the gradually changing parts 37 and 38 can be made by shape | molding the planar board | plate material connected back from the flat parts 35 and 36 in circular arc shape by press work. An example of this press working method will be specifically described. First, a plate material having an equal width is bent into a circular arc shape before being pressed. Then, the width dimension of the arc-shaped molded part increases as the curvature radius increases, and the width dimension decreases as the curvature radius decreases. Next, the arc-shaped formed portion is finished to have an equal width by performing outer peripheral punching, and the gradually changing portions 37 and 38 are formed. Then, the gradually changing portions 37 and 38 have a shorter length in the circumferential direction as the radius of curvature is larger (going forward) and longer in the circumferential direction as the radius of curvature is smaller (going backward).

The contact portions 33 and 34 may have a spherical shape, and the curvature radius in the insertion direction of the male terminal 1 may be the same as the curvature radius in the direction orthogonal to the insertion direction.
According to such a configuration, when the contact portions 33 and 34 are formed into a spherical shape, a cylinder having a simple shape is provided rather than providing the contact portions 33 and 34 immediately after the gradually changing portions 37 and 38 having complicated shapes. It is easier to form the contact portions 33 and 34 immediately after the portions 39 and 40, and the dimensions near the contact portions 33 and 34 can be easily managed quantitatively. As an example of such dimensional management, for example, the clearance between the apex 33T of the first contact portion 33 that makes point contact with the male terminal 1 and the opposing portion (vertex 34T of the second contact portion 34) facing this can be managed. Can be mentioned. Further, the merit of making the contact portions 33 and 34 spherical is that the position in contact with the male terminal 1 is fixed at one point, and the clearance can be inspected by image inspection, and the inspection becomes easy. Can be mentioned.

<Other embodiments>
The technology disclosed in the present specification is not limited to the embodiments described with reference to the above description and drawings, and includes, for example, the following various aspects.
(1) Although the shape of the gradually changing portions 37 and 38 is specified by the radius of curvature and the length in the circumferential direction in the above embodiment, the contact area with the male terminal 1 gradually decreases toward the rear. For example, the gradual change portion may have another form.

  (2) Although the male terminal 1 is initially in contact with the gradually changing portions 37 and 38 in the above embodiment, the male terminal 1 may be in contact with the flat portions 35 and 36 first.

  (3) In the above embodiment, the contact portions 33 and 34 are spherical, that is, the contact edge with the male terminal 1 is arcuate, but the contact edge with the male terminal 1 may be arcuate, Other than an arc shape may be used.

DESCRIPTION OF SYMBOLS 1 ... Male terminal 10 ... Female terminal 20 ... Fitting part 21 ... Bottom wall (peripheral wall)
23 ... Ceiling wall (surrounding wall)
DESCRIPTION OF SYMBOLS 30 ... Elastic piece 31 ... 1st elastic piece 32 ... 2nd elastic piece 33 ... 1st contact part 33A ... Contact surface 34 ... 2nd contact part 34A ... Contact surface 35 ... 1st flat part 35A ... Contact surface 35R ... Rear end 36 ... 2nd flat part 36A ... Contact surface 36R ... Rear end 37 ... 1st gradual change part 37A ... Contact surface 37R ... Rear end 38 ... 2nd gradual change part 38A ... Contact surface 38R ... Rear end 39 ... Cylindrical part 39A ... Contact surface 39B ... Same surface 39R ... Rear end 40 ... Second cylindrical portion 40A ... Contact surface 40B ... Same surface 40R ... Rear end

Claims (3)

A cylindrical portion formed by a plurality of peripheral walls, and a fitting portion into which a male terminal is fitted from the front,
An elastic piece arranged in the fitting portion and elastically contacting the male terminal;
This elastic piece
A flat portion extending rearward from the peripheral wall, the cross-sectional shape in the insertion direction of the male terminal is linear, and the cross-sectional shape in the direction orthogonal to the insertion direction is linear;
A gradual change portion extending rearward from the rear end of the flat portion, and the contact area with the male terminal gradually decreases toward the rear,
A cylindrical portion extending rearward from the rear end of the gradually changing portion, wherein the cross-sectional shape in the insertion direction of the male terminal is linear, and the cross-sectional shape in a direction orthogonal to the insertion direction is arcuate,
A contact portion extending rearward from the rear end of the cylindrical portion, the cross-sectional shape in the insertion direction of the male terminal is an arc shape, and the cross-sectional shape in a direction orthogonal to the insertion direction is an arc shape. ,
The contact surface with the male terminal in the flat part, the gradual change part, and the cylindrical part is a form that continues linearly when viewed from a direction orthogonal to the insertion direction,
The contact portion is a female terminal arranged in a region not exceeding a surface that is flush with a contact surface with the male terminal in the cylindrical portion.   The gradual change portion has a straight cross-sectional shape in the insertion direction of the male terminal, and a cross-section in a direction orthogonal to the insertion direction of the male terminal has an arc shape, and the male terminal in the gradual change portion and The female terminal according to claim 1, wherein the contact surface has a radius of curvature that increases toward the front and a length in a circumferential direction that increases toward the rear.   3. The female terminal according to claim 1, wherein the contact portion has a spherical shape, and a curvature radius in an insertion direction of the male terminal is the same as a curvature radius in a direction orthogonal to the insertion direction.

Images