Female terminal with resilient piece having a contact surface that gradually narrows to a contact point
09705222 ยท 2017-07-11
Assignee
- AUTONETWORKS TECHNOLOGIES, LTD. (JP)
- Sumitomo Wiring Systems, Ltd. (JP)
- Sumitomo Electric Industries, Ltd. (N/A)
Inventors
Cpc classification
International classification
H01R11/20
ELECTRICITY
Abstract
A female terminal (10) includes a tubular portion (14) configured to receive a male terminal (11) therein. Resilient pieces (23, 26) extend in from a bottom wall (15) and a ceiling wall (17) of the tubular portion (14) and contact the male terminal (11). Each resilient piece (23, 26) includes a line-contact portion (29, 31) that slides in line or surface contact with the male terminal (11), a contact portion (25, 28) to contact the male terminal (11), and a gradually changing portion (30, 32) formed from an end (29B, 31B) of the line-contact portion (29, 31) to a top (25A, 28A) of the contact portion (25, 28) and not protruding from a plane flush with a contact surface (29A, 31A) of the line-contact portion (29, 31). Thus, a contact area with the male terminal (11) is reduced gradually toward the contact portion (25, 28).
Claims
1. A female terminal, comprising: a tubular portion formed into a tubular shape by a plurality of peripheral walls and configured such that a male terminal is to be inserted; and a resilient piece formed to extend inwardly of the tubular portion from the peripheral wall and configured to resiliently come into contact with the male terminal, resilient piece including: a slide-contact portion capable of sliding in line or surface contact with the male terminal; a contact portion configured to come into point contact with the male terminal; and a gradually changing portion formed in an area from an end of the slide-contact portion to a top of the contact portion and not protruding from a plane flush with a contact surface of the slide-contact portion with the male terminal and configured such that a contact area with the male terminal is gradually reduced toward the contact portion.
2. The female terminal of claim 1, wherein a cutting line cutting the contact surface of the resilient piece with the male terminal in a longitudinal direction at a position passing through the top of the contact portion along an inserting direction of the male terminal is a straight line.
3. The female terminal of claim 2, wherein the gradually changing portion comes into line contact with the male terminal and a length of a contact edge of the gradually changing portion with the male terminal becomes gradually shorter toward the contact portion.
4. The female terminal of claim 3, wherein a contact surface of the male terminal with the gradually changing portion and a contact surface of the gradually changing portion with the male terminal are both flat surfaces.
5. The female terminal of claim 4, wherein a contact edge of the contact portion with the male terminal is arcuate.
6. The female terminal of claim 5, wherein: the peripheral wall includes a base end portion shaped to be folded inwardly of the tubular portion from a front end edge of the peripheral wall; and the resilient piece extends backward from the base end portion.
7. The female terminal of claim 6, wherein the plurality of peripheral walls include a bottom wall and a ceiling wall arranged to face the bottom wall, and wherein the resilient piece is formed on the bottom wall and the female terminal further comprising a second resilient piece formed on the ceiling wall.
8. The female terminal of claim 7, wherein a plurality of the resilient pieces are arranged over an entire area of the tubular portion in a direction intersecting with an inserting direction of the male terminal.
9. The female terminal of claim 1, wherein the gradually changing portion comes into line contact with the male terminal and a length of a contact edge of the gradually changing portion with the male terminal becomes gradually shorter toward the contact portion.
10. The female terminal of claim 1, wherein a contact surface of the male terminal with the gradually changing portion and a contact surface of the gradually changing portion with the male terminal are both flat surfaces.
11. The female terminal of claim 1, wherein a contact edge of the contact portion with the male terminal is arcuate.
12. The female terminal of claim 1, wherein: the peripheral wall includes a base end portion shaped to be folded inwardly of the tubular portion from a front end edge of the peripheral wall; and the resilient piece extends backward from the base end portion.
13. The female terminal of claim 1, wherein the plurality of peripheral walls include a bottom wall and a ceiling wall arranged to face the bottom wall, and wherein the resilient piece is formed on the bottom wall and the female terminal further comprising a second resilient piece formed on the ceiling wall.
14. The female terminal of claim 1, wherein the resilient piece comprises plural resilient pieces arranged over an entire area of the tubular portion in a direction intersecting with an inserting direction of the male terminal.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
(1)
(2)
(3)
(4)
(5)
(6)
(7)
(8)
(9)
(10)
(11)
(12)
(13)
(14)
DETAILED DESCRIPTION
(15) An embodiment of the present invention is described with reference to
(16) (Male Terminal 11)
(17) The male terminal 11 is formed by press-working a metal plate material into a predetermined shape. The male terminal 11 includes a male tab 12 in the form of a long and narrow plate and a contact surface of the male tab 12 with the female terminal 10 is a flat surface. Although the male terminal 11 is connected to an end of a wire 13 in this embodiment, it may be connected to an unillustrated device.
(18) (Female Terminal 10)
(19) The female terminal 10 is formed by press-working a metal plate material into a predetermined shape. The female terminal 10 includes a tubular portion 14 into which the male tab 12 of the male terminal 11 is to be inserted. As shown in
(20) The ceiling wall 17 is bent substantially at a right angle at the upper end edge of one of the pair of side walls 16 and extends toward the other side wall 16. A locking portion 18 is formed to project on a side end edge of the ceiling wall 17 and inserted into a locking hole 19 formed on the other side wall 16. A side end edge of the other side wall 16 is folded onto the upper surface of the ceiling wall 17. In this way, the tubular portion 14 is held in the rectangular tube shape.
(21) A wire barrel 20 extends behind the bottom wall 15. As shown in
(22) (First Resilient Piece 23)
(23) A first base end portion 24 is formed to project on the front end edge of the bottom wall 15. The first base end portion 24 is folded inwardly of the tubular portion 14 (backwardly) from the front end edge of the bottom wall 15. As shown in
(24) As shown in
(25) The respective first resilient pieces 23 are formed to have a substantially equal length in the front-back direction. Further, the respective first resilient pieces 23 are formed to have a substantially equal width in a direction perpendicular to the inserting direction of the male terminal 11 (hereinafter, referred to as a width direction). Further, intervals between adjacent resilient pieces 23 are both substantially equal. Thus, the plurality of first resilient pieces 23 are arranged substantially over the entire area of the tubular portion 14 in the width direction while being equally spaced apart.
(26) As shown in
(27) (Second Resilient Piece 26)
(28) A second base end portion 27 is formed to project on the front end edge of the ceiling wall 17. The second base end portion 27 is folded inwardly (backwardly) of the tubular portion 14 from the front end edge of the ceiling wall 17. As shown in
(29) As shown in
(30) The respective second resilient pieces 26 are formed to have a substantially equal length in the front-back direction. Further, the respective second resilient pieces 26 are formed to have a substantially equal width in a direction perpendicular to the inserting direction of the male terminal 11 (hereinafter, referred to as a width direction). Further, intervals between adjacent resilient pieces 26 are both substantially equal. Thus, the plurality of second resilient pieces 26 are arranged substantially over the entire area of the tubular portion 14 in the width direction while being equally spaced apart.
(31) As shown in
(32) As shown in
(33) (First Line Contact Portions and First Gradually Changing Portions)
(34) As shown in
(35) Both the contact surface 29A of the first line-contact portion 29 and the contact surface 30A of the first gradually changing portion 30 are flat surfaces and configured to come into line contact with the male terminal 11. A length of a contact edge with the male terminal 11 on the contact surface 29A of the first line-contact portion 29 is constant in the inserting direction of the male terminal 11, whereas a length of a contact edge with the male terminal 11 on the contact surface 30A of the first gradually changing portion 30 is longest at the end 29B of the first line-contact portion 29, becomes gradually shorter toward the first contact portion 25 and is shortest at the first contact portion 25. As shown in
(36) (Second Line Contact Portions and Second Gradually Changing Portions)
(37) As shown in
(38) Both the contact surface 31 A of the second line-contact portion 31 and the contact surface 32A of the second gradually changing portion 32 are flat surfaces and configured to come into line contact with the male terminal 11. A length of a contact edge with the male terminal 11 on the contact surface 31A of the second line-contact portion 31 is constant in the inserting direction of the male terminal 11, whereas a length of a contact edge with the male terminal 11 on the contact surface 32A of the second gradually changing portion 32 is longest at the end 31 B of the second line-contact portion 31, becomes gradually shorter toward the second contact portion 28 and is shortest at the second contact portion 28. As shown in
(39) (Functions and Effects of Embodiment)
(40) Next, functions and effects of this embodiment are described. When the male terminal 11 shown by solid line of
(41) When advancing further backward in the tubular portion 14, the male terminal 11 is inserted between the tops 25A of the first contact portions 25 and the tops 28A of the second contact portions 28 as shown in
(42) In the process of inserting the male terminal 11 into the tubular portion 14, a slant portion 12A at the tip of the male terminal 11 or an intersection 12C of the slant portion 12A and a horizontal portion 12B does not collide with each contact portion 25, 28 of each resilient piece 23, 26 from front as shown in
(43)
(44) Further, since the male terminal 11 is held in a similar point contact state with each contact portion 25, 28 before and after the twisting movement, a contact state of the male terminal 11 and each contact portion 25, 28 does not suddenly change and a sufficient contact pressure is ensued at any of the contact positions.
(45) As described above, in this embodiment, the male terminal 11 inserted into the tubular portion 14 advances while sliding in contact with each resilient piece 23, 26 and comes into point contact at each contact portion 25, 28. Here, in the process of the male terminal 11 reaching each contact portion 25, 28, the male terminal 11 is in line contact or surface contact with each gradually changing portion 30, 32. However, since the contact area of each gradually changing portion 30, 32 with the male terminal 11 is gradually reduced toward each contact portion 25, 28, a contact state of each resilient piece 23, 26 and the male terminal 11 smoothly transitions from line or surface contact to point contact in the process of inserting the male terminal 11 into the tubular portion 14. Note that the male terminal 11 inserted into the tubular portion 14 may move onto each gradually changing portion 30, 32 after contacting each line-contact portion 29, 31 or may directly contact each gradually changing portion 30, 32 without contacting each line-contact portion 29, 31.
(46) Since each gradually changing portion 30, 32 is formed in the area not protruding from the plane flush with the contact surface 29A, 31A of each line-contact portion 29, 31 with the male terminal 11, the slant portion 12A at the tip of the male terminal 11 or the intersection 12C of the slant portion 12A and the horizontal portion 12B does not move onto each gradually changing portion 30, 32 to increase the contact pressure when the tip of the male terminal 11 moves onto each gradually changing portion 30, 32 from the end 29B, 31B of each line-contact portion 29, 31. Further, since each gradually changing portion 30, 32 is formed to reach the top 25A, 28A of each contact portion 25, 28, the slant portion 12A at the tip of the male terminal 11 or the intersection 12C of the slant portion 12A and the horizontal portion 12B does not move onto each contact portion 25, 28 to increase the contact pressure when the tip of the male terminal 11 moves onto each contact portion 25, 28 from each gradually changing portion 30, 32. Accordingly, the peak value of the contact pressure becomes smaller, whereby the insertion force can be reduced. Further, in the female terminal 10 having the silver plating formed on the surface of each contact portion 25, 28 as in this embodiment, an effect that the silver plating is difficult to abrade even if the male terminal 11 is repeatedly inserted into and withdrawn from the female terminal 10 such as for maintenance is also obtained if the contact pressure is reduced.
(47) The cutting line cutting the contact surfaces 29A, 30A, 31A and 32A of the respective resilient pieces 23, 26 with the male terminal 11 in the longitudinal direction at the position passing through the tops 25A, 28A of the respective contact portions 25, 28 along the inserting direction of the male terminal 11 may be a straight line.
(48) According to this configuration, a ratio of a deflection amount of each resilient piece 23, 26 to an insertion distance of the male terminal 11 can be kept constant. Thus, a sudden change of the contact pressure can be avoided.
(49) Each gradually changing portions 30, 32 may come into line contact with the male terminal 11 and the length of the contact edge of each gradually changing portion 30, 32 with the male terminal 11 may become gradually shorter toward each contact portion 25, 28.
(50) According to this configuration, in the process of inserting the male terminal 11 into the tubular portion 14, the state of each resilient piece 23, 26 and the male terminal 11 changes from line contact to point contact. Thus, it can be avoided that the contact area with the male terminal 11 suddenly decreases to suddenly increase the contact pressure.
(51) A contact surface (male tab 12) of the male terminal 11 with each gradually changing portion 30, 32 and the contact surface 30A, 32A of each gradually changing portion 30, 32 with the male terminal 11 may be both flat surfaces.
(52) According to this configuration, the contact surface 30A, 32A of each gradually changing portion 30, 32 and the contact surface (male tab 12) of the male terminal 11 contact each other, wherefore the male terminal 11 can be inserted in a stable posture.
(53) The contact edge 25B, 28B of each contact portion 25, 28 with the male terminal 11 may be arcuate.
(54) According to this configuration, if either one of the male terminal 11 and the female terminal 10 is twisted about the axis extending in the inserting direction of the male terminal 11 into the tubular portion 14, the male terminal 11 can be held in point contact before, during and after a twisting movement. Note that the point contact of each contact portion 25, 28 with the male terminal 11 means that the position of each contact portion 25, 28 is clarified. Associated with this, a gap control between each contact portion 25, 28 and a part facing this (between the respective contact portions 25 and 28 in this embodiment), which is one of control items in manufacturing the female terminal 10, becomes easier.
(55) The peripheral walls (bottom wall 15, ceiling wall 17) may include each base end portion 24, 27 folded inwardly of the tubular portion 14 from the front end edge of the peripheral wall and each resilient piece 23, 26 may extend backward from each base end portion 24, 27.
(56) According to this configuration, the collision of external matters with each resilient piece 23, 26 is easily avoided. Further, since each base end portion 24, 27 has a higher rigidity than each resilient piece 23, 26, each base end portion 24, 27 is hard to deform even if an external matter collides with each base end portion 24, 27. Since this suppresses a displacement of each resilient piece 23, 26 in the tubular portion 14 due to the collision of the external matter, a stable contact pressure can be applied to the male terminal 11.
(57) The plurality of peripheral walls may include the bottom wall 15 and the ceiling wall 17 arranged to face this bottom wall 15, and the resilient piece may be composed of the first resilient piece 23 formed on the bottom wall 15 and the second resilient piece 26 formed on the ceiling wall 17.
(58) According to this configuration, the male terminal 11 is sandwiched between the first and second resilient pieces 23, 26, wherefore an increase of the contact pressure can be avoided by both the first and second resilient pieces 23, 26.
(59) A plurality of resilient pieces 23 and a plurality of resilient pieces 26 may be arranged over the entire area of the tubular portion 14 in the direction intersecting with the inserting direction of the male terminal 11.
(60) According to this configuration, the number of contacts with the male terminal 11 increases, wherefore contact resistance with the male terminal 11 can be reduced, which is preferable for a terminal for large current application.
(61) The present invention is not limited to the above described and illustrated embodiment. For example, the following embodiments are also included in the technical scope of the present invention.
(62) Although the core 22 of the wire 13 is crimped and connected to the wire barrel 20 in the above embodiment, resistance welding, ultrasonic welding, soldering or the like may be used as a connection method of the core 22 and the female terminal 10 according to the present invention.
(63) Although the male terminal 11 is sandwiched between the resilient pieces 23, 26 arranged to vertically face each other in the above embodiment, a resilient piece may be provided on either one side and the male terminal 11 may be sandwiched between this resilient piece and the peripheral wall facing this according to the present invention. Further, although the plurality of resilient pieces are arranged side by side in the direction intersecting with the inserting direction of the male terminal 11 in the above embodiment, only one resilient piece may be provided in the direction intersecting with the inserting direction of the male terminal 11 according to the present invention.
(64) Although each resilient piece 23, 26 is formed to extend backward from each base end portion 24, 27 in the above embodiment, each resilient piece may be formed to extend forward from a rear end part of the tubular portion 14 according to the present invention.
(65) Although each gradually changing portion 30, 32 is formed to be flush with the plane flush with the contact surface 29A, 31A of each line-contact portion 29, 31 with the male terminal 11 in the above embodiment, the first gradually changing portion may be formed below the plane flush with the contact surface 29A of the first line-contact portion 29 and the second gradually changing portion may be formed above the plane flush with the contact surface 31A of the second line-contact portion 31 according to the present invention.
(66) Although the male terminal 11 in the form of a flat plate is illustrated in the above embodiment, a male terminal in the form of a round bar may be adopted according to the present invention. In this case, a resilient piece of a female terminal may be formed into a cylindrical shape.
(67) Although the length of the contact edge of each gradually changing portion 30, 32 with the male terminal 11 becomes gradually shorter toward each contact portion 25, 28 in the above embodiment, a section extending toward each contact portion 25, 28 while having the constant length of the contact edge with the male terminal 11 may be provided in a part of each gradually changing portion according to the present invention.
(68) Although the contact edge 25B, 28B of each contact portion 25, 28 is arc-like in the above embodiment, the contact edge of each contact portion has only to be arcuate and may have a shape other than an arc-like shape according to the present invention.
(69) Although the respective resilient pieces 23, 26 are formed on the bottom wall 15 and the ceiling wall 17 of the tubular portion 14 in the above embodiment, resilient pieces may be formed on the side walls 16 according to the present invention.
(70) Although each resilient piece 23, 26 is formed on each base end portion 24, 27 after the base end portions 24, 27 are formed on the bottom wall 15 and the ceiling wall 17 in the above embodiment, each resilient piece may be directly formed on the bottom wall 15 and the ceiling wall 17 without providing any base end portion according to the present invention.
(71) Although the first and second line-contact portions 29, 31 are illustrated as slide-contact portions in the above embodiment, surface-contact portions configured to come into surface contact with the male terminal 11 may be adopted as the slide-contact portions according to the present invention.
LIST OF REFERENCE SIGNS
(72) 10 . . . female terminal 11 . . . male terminal 12 . . . male tab (contact surface) 14 . . . tubular portion 15 . . . bottom wall (peripheral wall) 17 . . . ceiling wall (peripheral wall) 23 . . . first resilient piece 24 . . . first base end portion 25 . . . first contact portion 25A . . . top 25B . . . contact edge 26 . . . second resilient piece 27 . . . second base end portion 28 . . . second contact portion 28A . . . top 28B . . . contact edge 29 . . . first line-contact portion (slide-contact portion) 29A . . . contact surface 29B . . . end 30 . . . first gradually changing portion 30A . . . contact surface 30B . . . non-contact surface 31 . . . second line-contact portion (slide-contact portion) 31A . . . contact surface 31B . . . end 32 . . . second gradually changing portion 32A . . . contact surface 32B . . . non-contact surface