JP2016173889A - Electrical contact pair and terminal pair for connector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrical contact pair and a terminal pair for connector capable of reducing the wear volume in the contact portion at the time of sliding.SOLUTION: An electrical contact pair 1 has a first electrical contact 11, a second electrical contact 12, and a contact portion 13. The first electrical contact 11 includes a first Ag-Sn alloy layer 113 above a first conductive base material 111, and a first Ag layer 114 laminated on the surface of the first Ag-Sn alloy layer 113, and the first Ag layer 114 is exposed to the outermost surface. The second electrical contact 12 includes a second Ag-Sn alloy layer 123 above a second conductive base material 121, and a second Ag layer 124 laminated on the surface of the second Ag-Sn alloy layer 123, and the second Ag layer 124 is exposed to the outermost surface. The contact portion 13 is formed by contact of the surface of the first Ag layer 114 at the first electrical contact 11 and the surface of the second Ag layer 124 at the second electrical contact 12. A contact pressure applied to the contact portion 13 is equal to or less than 630 N/mm.SELECTED DRAWING: Figure 7

Description

  The present invention relates to an electrical contact pair and a connector terminal pair.

  In recent years, with the spread of hybrid vehicles and electric vehicles, high-current connector terminals are used for power supply lines for supplying power to motors and the like. Usually, Ag plating having a low contact resistance is used for electrical contacts in this type of connector terminal. When the connector terminals are fitted together, the Ag layers of the electrical contacts come into contact with each other, and a contact portion in the electrical contact pair is formed.

  As the connector terminal, for example, in Patent Document 1, a base material made of Cu or a Cu alloy, an Ag—Sn alloy layer covering the surface of the base material, and an Ag—Sn alloy layer are coated on the outermost surface. A connector terminal made of a plated member having an exposed Ag layer is disclosed.

JP2013-231228A

  However, the conventional technology has room for improvement in the following points. That is, Ag is a metal that is relatively soft and easy to adhere. Therefore, an electrical contact pair having a contact portion formed by contacting Ag layers is likely to wear due to adhesion of Ag and is inferior in wear resistance. In particular, when friction due to sliding acts on the electrical contact pair, wear due to the adhesion becomes significant. When severe wear occurs, the base material exposed on the surface or the lower layer having a higher contact resistance than the Ag layer constitutes the contact portion, so that the connection reliability of the connector terminal pair decreases.

  In this regard, in Patent Document 1, by providing a relatively hard Ag—Sn alloy layer under the Ag layer, the surface friction coefficient is reduced, and the wear resistance of the electrical contact pair is ensured. However, even when such a configuration is employed, the amount of wear during sliding at the contact portion may not be sufficiently reduced.

  The present invention has been made in view of the above-described background, and an object of the present invention is to provide an electrical contact pair and a connector terminal pair that can reduce the amount of wear at the time of sliding in the contact portion.

One embodiment of the present invention includes a first Ag—Sn alloy layer and a first Ag layer laminated on a surface of the first Ag—Sn alloy layer above the first conductive base material, the first Ag layer being A first electrical contact exposed on the outermost surface;
A second Ag-Sn alloy layer and a second Ag layer laminated on the surface of the second Ag-Sn alloy layer are provided above the second conductive base material, and the second Ag layer is exposed on the outermost surface. A second electrical contact;
A contact portion formed by contacting the surface of the first Ag layer in the first electrical contact with the surface of the second Ag layer in the second electrical contact;
A contact pressure applied to the contact portion is 630 N / mm ² or less.

  Another aspect of the present invention is a connector terminal pair having the electrical contact pair.

The electrical contact pair has a contact portion formed by contacting the surface of the first Ag layer in the first electrical contact with the surface of the second Ag layer in the second electrical contact. Here, the 1st electrical contact has the 1st Ag-Sn alloy layer harder than the 1st Ag layer under the 1st Ag layer. For this reason, the first electrical contact has a lower coefficient of friction on the outermost surface, and wear resistance during sliding is improved. Moreover, the 2nd electrical contact has the 2nd Ag-Sn alloy layer harder than the 2nd Ag layer under the 2nd Ag layer. Therefore, the second electrical contact has a smaller coefficient of friction on the outermost surface and improves the wear resistance during sliding. Further, in the electrical contact pair, the contact pressure applied to the contact portion is 630 N / mm ² or less. That is, in the electrical contact pair, the contact pressure applied to the contact portion formed using the first electrical contact and the second electrical contact having the above-described configuration is limited to 630 N / mm ² or less. Therefore, the electrical contact pair can reduce the amount of wear at the time of sliding at the contact portion as compared with the case where the contact pressure applied to the contact portion exceeds 630 N / mm ² .

  The connector terminal pair includes the electrical contact pair. Therefore, the connector terminal pair can reduce the amount of wear during sliding at the contact portion. Therefore, the connector terminal pair can maintain high connection reliability.

FIG. 3 is a cross-sectional view schematically showing an electrical contact pair of Example 1. FIG. 3 is a cross-sectional view schematically illustrating a connector terminal pair according to the first embodiment. 6 is a cross-sectional view schematically showing an electric contact pair of Example 2. FIG. 10 is a cross-sectional view schematically showing an electrical contact pair of Example 3. FIG. 5 is a VV cross-sectional view schematically showing a connector terminal pair of Example 3. FIG. 6 is a VI-VI cross-sectional view schematically showing a connector terminal pair of Example 3. FIG. It is the graph which showed the relationship between the contact pressure (N / mm < ² >) concerning a contact part, and the abrasion volume (micrometer < ³ >) obtained by the experiment example.

In the electric contact pair, the contact pressure applied to the contact portion is 630 N / mm ² or less. The contact pressure applied to the contact portion can be calculated by dividing the load (N) applied to the contact portion by the contact area (mm ² ) between the first Ag layer and the second Ag layer in the contact portion.

Contact pressure applied to the contact portion, the wear amount at the time of sliding from the viewpoint of easily reducing the at contact portions, preferably 628N / mm ² or less, more preferably 625N / mm ² or less, more preferably 623N / mm ² or less Even more preferably, it can be 620 N / mm ² or less, and even more preferably 618 N / mm ² or less. In addition, the minimum of the contact pressure concerning a contact part is not specifically limited from a viewpoint of reducing the abrasion amount at the time of sliding in a contact part. The lower limit of the contact pressure applied to the contact portion can be set so as to ensure electrical contact in consideration of the terminal shape, the size of the terminal, and the like.

  In the electrical contact pair, the first electrical contact includes a first Ag—Sn alloy layer and a first Ag layer laminated on the surface of the first Ag—Sn alloy layer above the first conductive base material. The 1Ag layer is exposed on the outermost surface. The first Ag—Sn alloy layer may not be in contact with the first conductive base material or may be in contact with the first conductive base material as long as it is disposed above the first conductive base material. . In the former case, one or more other metal (including alloy, omitted) layers are interposed between the first conductive base material and the first Ag—Sn alloy layer as necessary. Can do. That is, the first electrical contact includes a first conductive base material, a first Ag—Sn alloy layer laminated on the surface of the first conductive base material directly or via another metal layer, and a first Ag—Sn alloy. A first Ag layer laminated on the surface of the layer, and the first Ag layer may be exposed on the outermost surface.

  In the electrical contact pair, the second electrical contact includes a second Ag-Sn alloy layer and a second Ag layer laminated on the surface of the second Ag-Sn alloy layer above the second conductive base material. The 2Ag layer is exposed on the outermost surface. The second Ag—Sn alloy layer may not be in contact with the second conductive base material or may be in contact with the second conductive base material as long as it is disposed above the second conductive base material. . In the former case, one or more other metal layers can be interposed between the second conductive base material and the second Ag—Sn alloy layer as necessary. That is, the second electrical contact includes a second conductive base material, a second Ag—Sn alloy layer laminated on the surface of the second conductive base material directly or via another metal layer, and a second Ag—Sn alloy. A second Ag layer laminated on the surface of the layer, and the second Ag layer may be exposed on the outermost surface.

  The electrical contact pair includes a Ni layer and / or between the first conductive base material and the first Ag—Sn alloy layer and / or between the second conductive base material and the second Ag—Sn alloy layer. It can be set as the structure which has Ni alloy layer.

  The Ni layer and the Ni alloy layer have high heat resistance. Therefore, in this case, even when the electrical contact pair is exposed to a high temperature environment, an oxide-forming element (for example, a conductive layer) that diffuses from the bottom of the Ni layer or Ni alloy layer toward the surface. Cu component, etc. of the conductive base material) can be blocked by the Ni layer or Ni alloy layer. For this reason, it is difficult to form an insulating oxide at the contact portion, and an increase in contact resistance is easily suppressed.

  In the electrical contact pair, the first conductive base material and the second conductive base material can be made of copper or copper alloy, or aluminum or aluminum alloy.

  When the first conductive base material and the second conductive base material are made of copper or a copper alloy, an electrical contact pair suitable for a connector terminal pair using copper or a copper alloy as the conductive base material is obtained. Further, when the first conductive base material and the second conductive base material are made of aluminum or an aluminum alloy, an electrical contact pair suitable for a connector terminal pair using aluminum or an aluminum alloy as the conductive base material is obtained. It is done.

  In the electrical contact pair, the first electrical contact has a protruding shape, and the second electrical contact has a plate shape that is in electrical contact with the top of the protruding first electrical contact. be able to. In addition, the second electrical contact may have a protruding shape, and the first electrical contact may have a plate shape that is in electrical contact with the top of the protruding second electrical contact. In addition, in the electrical contact pair, the first electrical contact has a bent portion, and the second electrical contact has a plate shape that is in electrical contact with the bent portion of the first electrical contact. be able to. The second electrical contact may have a bent portion, and the first electrical contact may have a plate shape that comes into electrical contact with the bent portion of the second electrical contact.

  In the electric contact pair, the thickness of the first Ag layer may be thinner than the thickness of the first Ag—Sn alloy layer. Further, the thickness of the second Ag layer can be made thinner than the thickness of the second Ag—Sn alloy layer. In this case, the effect of reducing the friction coefficient of the outermost surface of the first electrical contact by having the relatively hard first Ag—Sn alloy layer under the first Ag layer, and the relatively hard second Ag under the second Ag layer. Both of the effects of reducing the friction coefficient of the outermost surface of the second electrical contact by having the Sn alloy layer are exhibited. Therefore, in this case, even when the contact load applied to the contact portion is a large load within the range of the specific upper limit value or less, it is easy to reduce the amount of wear during sliding at the contact portion.

  The connector terminal pair has the electrical contact pair. The connector terminal pair may have one electrical contact pair or a plurality of electrical contact pairs. In addition to the electrical contact pair, the connector terminal pair may have an electrical contact pair having a configuration different from that of the electrical contact pair. In the connector terminal pair, preferably, all of the electrical contact pairs included in the connector terminal pair are constituted by the electrical contact pair. In this case, since it becomes possible to reduce the abrasion amount at the time of sliding in all the contact parts, the connector terminal pair which can maintain high connection reliability easily is obtained.

  Specifically, the connector terminal pair has a first terminal having a first electrical contact and a second terminal having a second electrical contact, and the first terminal and the second terminal are fitted to each other. By doing so, the contact portion can be formed. In this case, a connector terminal pair having the electrical contact pair can be obtained with certainty.

  More specifically, for example, the first terminal can have a female terminal shape having a projection as a first electrical contact, and the second terminal can serve as a second electrical contact that contacts the top of the projection. The male terminal shape which has the plate-shaped part of this can be exhibited. In this case, the first terminal can have one or more protrusions, and the second terminal can have one or more plate-like portions. Further, the second terminal can have a female terminal shape having a protrusion as a second electric contact, and the first terminal has a plate-like portion as a first electric contact that contacts the top of the protrusion. A male terminal shape can be exhibited. In this case, the second terminal can have one or more protrusions, and the first terminal can have one or more plate-like portions.

  Further, for example, the first terminal can have a female terminal shape having a bent portion as a first electric contact, and the second terminal is a male having a plate-like portion as a second electric contact in contact with the bent portion. A mold terminal shape can be exhibited. In this case, the first terminal can have one or more bent portions, and the second terminal can have one or more plate-like portions. Further, the second terminal can have a female terminal shape having a bent portion as a second electric contact, and the first terminal has a male shape having a plate-like portion as a first electric contact in contact with the bent portion. A terminal shape can be exhibited. In this case, the second terminal can have one or more bent portions, and the first terminal can have one or more bent portions.

  In addition, each structure mentioned above can be arbitrarily combined as needed, in order to acquire each effect etc. which were mentioned above.

  Hereinafter, the electrical contact pair and the connector terminal pair of the embodiment will be described with reference to the drawings.

Example 1
The electrical contact pair and connector terminal pair of Example 1 will be described with reference to FIGS. As shown in FIG. 1, the electrical contact pair 1 of this example includes a first electrical contact 11, a second electrical contact 12, and a contact portion 13. The first electrical contact 11 includes a first Ag—Sn alloy layer 113 and a first Ag layer 114 laminated on the surface of the first Ag—Sn alloy layer 113 above the first conductive base material 111. In the first electrical contact 11, the first Ag layer 114 is exposed on the outermost surface. The second electrical contact 12 includes a second Ag—Sn alloy layer 123 and a second Ag layer 124 laminated on the surface of the second Ag—Sn alloy layer 123 above the second conductive base material 121. In the second electrical contact 12, the second Ag layer 124 is exposed on the outermost surface. In each electrical contact 11, 12, each layer forming side is set on the upper side with respect to each conductive base material 111, 121. The contact portion 13 is formed by contacting the surface of the first Ag layer 114 in the first electrical contact 11 and the surface of the second Ag layer 124 in the second electrical contact 12. The contact pressure applied to the contact portion 13 is 630 N / mm ² or less. This will be described in detail below.

  In this example, the first electrical contact 11 has a protruding shape. Specifically, the first electrical contact 11 includes a first conductive base material 111 formed in a protruding shape, a Ni layer 112 stacked on the surface of the first conductive base material 111, and a surface of the Ni layer 112. The first Ag—Sn alloy layer 113 and the first Ag layer 114 stacked on the surface of the first Ag—Sn alloy layer 113 are provided. The first conductive base material 111 is made of copper or a copper alloy and has a thickness of 250 μm. The thickness of the Ni layer 112 is 1 μm. The thickness of the first Ag—Sn alloy layer 113 is 4 μm. The thickness of the first Ag layer 114 is 1 μm.

  On the other hand, in this example, the second electrical contact 12 has a plate shape that is in electrical contact with the top of the protruding first electrical contact 11. Specifically, the second electrical contact 12 includes a plate-shaped second conductive base material 121, a Ni layer 122 stacked on the surface of the second conductive base material 121, and a surface of the Ni layer 122. And a second Ag-Sn alloy layer 123 laminated on the surface, and a second Ag layer 124 laminated on the surface of the second Ag-Sn alloy layer 123. The second conductive base material 121 is made of copper or a copper alloy and has a thickness of 250 μm. The thickness of the Ni layer 122 is 1 μm. The thickness of the second Ag—Sn alloy layer 123 is 4 μm. The thickness of the second Ag layer 124 is 1 μm. The Ni layer 112 of the first electrical contact 11 and the Ni layer 122 of the second electrical contact 12 can be changed to Ni alloy layers.

  Next, as shown in FIG. 2, the connector terminal pair 2 of this example has an electrical contact pair 1. The details will be described below.

In this example, the connector terminal pair 2 includes a first terminal 21 having the first electrical contact 11 and a second terminal 22 having the second electrical contact 12. In the connector terminal pair 2, the contact portion 13 is formed by fitting the first terminal 21 and the second terminal 22. In this example, the first terminal 21 has one first electrical contact 11, and the second terminal 22 has one second electrical contact 12. Therefore, the connector terminal pair 2 of this example has one electrical contact pair 1 and one contact portion 13 having a contact pressure of 630 N / mm ² or less.

  The connector terminal pair 2 is used for an automobile wire harness (not shown). More specifically, the connector terminal pair 2 is applied to a power supply line through which a large current flows in an automobile. Specifically, the first terminal 21 is a female terminal. Specifically, the second terminal 22 is a male terminal.

  More specifically, the 1st terminal 21 has the cylindrical part 212 which the insertion port 211 opened to the front end. On the other hand, the second terminal 22 has a plate-like portion 221 for insertion into the insertion port 211 of the first terminal 21. Inside the tubular portion 212 of the first terminal 21, there is provided an elastic contact piece 214 formed by folding the bottom plate 213 inward and rearward. The elastic contact piece 214 is for applying an upward force to the plate-like portion 221 of the inserted second terminal 22. The plate-like portion 221 of the second terminal 22 is pressed against the inner surface of the ceiling plate 215 of the tubular portion 212 by the elastic contact piece 214. As a result, the plate-like portion 221 of the second terminal 22 is held between the elastic contact piece 214 and the inner surface of the ceiling plate 215 in a compressed state.

  A protrusion 216 is formed on the elastic contact piece 214. The protrusion 216 is formed by causing the elastic contact piece 214 to swell in a hemispherical shape from the back side to the surface. In this example, the protrusion 216 of the elastic contact piece 214 is the first electrical contact 11. Further, in the plate-like portion 221 of the second terminal 22, a portion that contacts the top portion of the protruding portion 216 and its peripheral portion serve as the second electrical contact 12.

  In this example, the portion of the first terminal 21 other than the elastic contact piece 214 including the first electrical contact 11 has a Ni layer laminated on the surface of a conductive base material made of copper or a copper alloy, and the surface of the Ni layer. An Sn layer or an Sn alloy layer is laminated on the substrate. The conductive base material constituting the first terminal 21 is continuous with the first conductive base material 111 of the first electrical contact 11. Further, a portion (not shown) other than the plate-like portion 221 including the second electrical contact 12 in the second terminal 22 has a Ni layer laminated on the surface of a conductive base material made of copper or a copper alloy, and the surface of the Ni layer. An Sn layer or an Sn alloy layer is laminated on the substrate. The conductive base material constituting the second terminal 22 is continuous with the second conductive base material 121 of the second electrical contact 12.

  Next, the effect of the electrical contact pair and connector terminal pair of this example will be described.

The electrical contact pair 1 of this example has a contact portion 13 formed by contacting the surface of the first Ag layer 114 in the first electrical contact 11 and the surface of the second Ag layer 124 in the second electrical contact 12. Here, the first electrical contact 11 has a first Ag—Sn alloy layer 113 harder than the first Ag layer 114 under the first Ag layer 114. Therefore, the first electrical contact 11 has a smaller coefficient of friction on the outermost surface and improves wear resistance during sliding. The second electrical contact 12 has a second Ag—Sn alloy layer 123 harder than the second Ag layer 124 under the second Ag layer 124. Therefore, the second electrical contact 12 has a smaller coefficient of friction on the outermost surface, and wear resistance when sliding is improved. Further, in the electrical contact pair 1 of this example, the contact pressure applied to the contact portion 13 is 630 N / mm ² or less. That is, in the electrical contact pair 1 of this example, the contact pressure applied to the contact portion 13 configured using the first electrical contact 11 and the second electrical contact 12 having the above configuration is limited to 630 N / mm ² or less. . Therefore, the electrical contact pair 1 of this example can reduce the amount of wear at the time of sliding in the contact portion 13 as compared with the case where the contact pressure applied to the contact portion 13 exceeds 630 N / mm ² .

  The connector terminal pair 2 of this example has the electrical contact pair 1 of this example. Therefore, the connector terminal pair 2 of the present example can reduce the amount of wear when the contact portion 13 slides. Therefore, the connector terminal pair 2 of this example can maintain high connection reliability.

(Example 2)
The electrical contact pair and connector terminal of Example 2 will be described with reference to FIG. As shown in FIG. 3, in the electrical contact pair 1 of this example, the second electrical contact 12 has a protruding shape. Specifically, the second electrical contact 12 includes a second conductive base material 121 formed in a protruding shape, a Ni alloy layer 122 laminated on the surface of the second conductive base material 121, and a Ni alloy layer 122. The 2nd Ag-Sn alloy layer 123 laminated | stacked on the surface of this, and the 2nd Ag layer 124 laminated | stacked on the surface of the 2nd Ag-Sn alloy layer 123 are provided. The second conductive base material 121 is made of copper or a copper alloy and has a thickness of 250 μm. The thickness of the Ni alloy layer 122 is 1 μm. The thickness of the second Ag—Sn alloy layer 123 is 4 μm. The thickness of the second Ag layer 124 is 1 μm.

  On the other hand, in this example, the first electrical contact 11 has a plate shape that is in electrical contact with the top of the protruding second electrical contact 12. Specifically, the first electrical contact 11 includes a first conductive base material 111 formed in a plate shape, a Ni alloy layer 112 stacked on the surface of the first conductive base material 111, and a Ni alloy layer 112. A first Ag—Sn alloy layer 113 laminated on the surface of the first Ag layer, and a first Ag layer 114 laminated on the surface of the first Ag—Sn alloy layer 113. The first conductive base material 111 is made of copper or a copper alloy and has a thickness of 250 μm. The thickness of the Ni alloy layer 112 is 1 μm. The thickness of the first Ag—Sn alloy layer 113 is 4 μm. The thickness of the first Ag layer 114 is 1 μm. About another structure, it has the structure similar to the electrical contact pair 1 of Example 1. FIG.

  In the connector terminal pair (not shown) of this example, the first terminal is a male terminal, and the second terminal is a female terminal. That is, the connector terminal pair of this example has the male and female configurations opposite to those of the connector terminal pair of the first embodiment. Therefore, in this example, the protrusion of the elastic contact piece is the second electrical contact. Moreover, the part which contacts the top part of a projection part among the plate-shaped parts of a 1st terminal, and its peripheral part are made into a 1st electrical contact. About another structure, it has the structure similar to the terminal pair for connectors of Example 1. FIG.

  The electrical contact pair and connector terminal pair of this example can achieve the same effects as the electrical contact pair and connector terminal pair of Example 1.

(Example 3)
The electrical contact pair and connector terminal of Example 3 will be described with reference to FIGS. As shown in FIG. 4, the first electrical contact 11 of this example has a bent portion 218. Specifically, the first electrical contact 11 includes a first conductive base material 111 that is bent so as to have a bent portion 218, and a first Ag—Sn alloy laminated on the surface of the first conductive base material 111. The layer 113 and the 1st Ag layer 114 laminated | stacked on the surface of the 1st Ag-Sn alloy layer 113 are provided. The first conductive base material 111 is made of aluminum or an aluminum alloy and has a thickness of 250 μm. The thickness of the first Ag—Sn alloy layer 113 is 4 μm. The thickness of the first Ag layer 114 is 1 μm.

  On the other hand, in this example, the second electrical contact 12 has a plate shape that is in electrical contact with the bent portion 218 of the first electrical contact 11. Specifically, the second electrical contact 12 includes a second conductive base material 121 formed in a plate shape, a second Ag—Sn alloy layer 123 stacked on the surface of the second conductive base material 121, The second Ag layer 124 is laminated on the surface of the 2Ag—Sn alloy layer 123. The second conductive base material 121 is made of aluminum or an aluminum alloy and has a thickness of 250 μm. The thickness of the second Ag—Sn alloy layer 123 is 4 μm. The thickness of the second Ag layer 124 is 1 μm. About another structure, it has the structure similar to the electrical contact pair 1 of Example 1. FIG.

  As shown in FIGS. 5 and 6, the connector terminal pair 2 of the present example is similar to the connector terminal pair 1 of the first embodiment, the first terminal 21 having the first electrical contact 11, And a second terminal 22 having the second electrical contact 12. In the connector terminal pair 2, the contact portion 13 is formed by fitting the first terminal 21 and the second terminal 22.

However, in this example, the first terminal 21 has six first electric contacts 11, and the second terminal 22 has six second electric contacts 12 in one plate-like portion 212. . Therefore, the connector terminal pair 2 of this example has six electrical contact pairs 1 and six contact portions 13 having a contact pressure of 630 N / mm ² or less. That is, the connector terminal pair 2 has a plurality of electrical contact pairs, and all the electrical contact pairs are constituted by the electrical contact pair 1.

  More specifically, inside the cylindrical portion 212 of the first terminal 21, there are provided three pairs of elastic contact pieces 214 formed by folding the top plate 217 and the bottom plate 213 inward and rearward. Yes. Each of the three elastic contact pieces 214 arranged on the top plate 217 side is for applying a downward force to the plate-like portion 221 of the inserted second terminal 22. Further, the three elastic contact pieces 214 arranged on the bottom plate 213 side so as to face the three elastic contact pieces 214 arranged on the top surface plate 217 side are plate-like of the inserted second terminal 22. This is for applying an upward force to the portion 221. Accordingly, the plate-like portion 221 of the second terminal 22 is held in a sandwiched state by the three pairs of elastic contact pieces 214.

  Each elastic contact piece 214 is formed with a bent portion 218. The bent portion 218 is formed by bending and bending the distal end portion of the elastic contact piece 214 to the side opposite to the second terminal 22 side. In this example, the bent portion 218 of the elastic contact piece 214 is the first electrical contact 11. Further, in the plate-like portion 221 of the second terminal 22, a portion that contacts the top of the bent portion 218 and its peripheral portion serve as the second electrical contact 12. About another structure, it has the structure similar to the terminal pair 1 for connectors of Example 1. FIG.

  The electrical contact pair and connector terminal pair of this example can achieve the same effects as the electrical contact pair and connector terminal pair of Example 1.

<Experimental example>
Hereinafter, it demonstrates more concretely using an experiment example.

-Preparation of test piece-
An Ni plating film having a thickness of 1 μm was formed on the surface of a clean copper alloy plate having a thickness of 250 μm by electrolytic plating. Next, an Ag plating film having a thickness of 1.3 μm, an Sn plating film having a thickness of 1.4 μm, and an Ag plating film having a thickness of 2.3 μm are sequentially formed on the surface of the Ni plating film by electrolytic plating at 290 ° C. Reflowed. Thereby, a Ni layer (thickness 1 μm), an Ag—Sn alloy layer (thickness 4 μm), and an Ag layer (thickness 1 μm) were formed in this order on the surface of the copper alloy plate. Next, a substantially hemispherical protrusion was formed by bulging a part of this copper alloy plate from the back side to the front side so as to have a curvature radius of 3 mm. Thereby, a test piece 1A was obtained. In addition, 1 A of test pieces simulate the 1st electrical contact which comprises an electrical contact pair.

  Further, in the production of the test piece 1A, a test piece 1B was obtained in the same manner except that a substantially hemispherical projection having a curvature radius of 1 mm was formed. In addition, the test piece 1B simulates the 1st electrical contact which comprises an electrical contact pair.

  Further, a 1 μm thick Ni plating film was formed on the surface of a clean copper alloy plate having a thickness of 250 μm by electrolytic plating. Next, an Ag plating film having a thickness of 1.3 μm, an Sn plating film having a thickness of 1.4 μm, and an Ag plating film having a thickness of 2.3 μm are sequentially formed on the surface of the Ni plating film by electrolytic plating at 290 ° C. Reflowed. Thereby, the test piece 2 which has a Ni layer (thickness 1 micrometer), an Ag-Sn alloy layer (thickness 4 micrometers), and an Ag layer (thickness 1 micrometer) in this order on the surface of the copper alloy board was obtained. In addition, the test piece 2 simulates the 2nd electrical contact which comprises an electrical contact pair.

-Friction and wear test-
The top of the protrusion of the test piece 1A or the test piece 1B is held in a state of being in contact with the Ag layer of the test piece 2 in the vertical direction, and a predetermined load (N) shown in Table 1 in the vertical direction using a piezo actuator. Was applied. This simulates an electrical contact pair having a contact portion formed by bringing the test piece 1A or the test piece 1B and the test piece 2 into contact with each other. Next, while applying the predetermined load, 10 mm / min. The test piece 1A or the test piece 1B was pulled 25 mm in the horizontal direction at a speed of 2 mm, and both test pieces were slid. Then, the protrusion part was observed and the area of the sliding trace was calculated | required. The area of the sliding trace is simply regarded as the contact area (mm ² ) at the contact portion between the test piece 1A or the test piece 1B and the test piece 2, and the applied load is divided by the contact area. Thus, the contact pressure (N / mm ² ) was obtained. In addition, using a confocal microscope (“OPTELICS H1200” manufactured by Lasertec Corporation), the distance between the tip of the protrusion before the test and the surface of the sliding mark formed on the protrusion after the test was measured, and sliding A value obtained by multiplying the area of the mark by the above distance was simply obtained as a wear volume (μm ³ ). The results are summarized in Table 1. FIG. 7 shows the relationship between the contact pressure (N / mm ² ) applied to the contact portion and the wear volume (μm ³ ).

According to Table 1 and FIG. 7, it can be seen that when the contact pressure applied to the contact portion exceeds 630 N / mm ² , the wear volume rapidly increases. In this example, the contact pressure applied to the contact portion is 100 N / mm ² or more, more specifically 200 N / mm ² or more, but the contact pressure applied to the contact portion is 630 N / mm ² or less. It can be seen that a sharp increase in the wear volume is suppressed. From this result, by limiting the contact pressure applied to the contact portion to 630 N / mm ² or less, the amount of wear at the time of sliding at the contact portion compared to the case where the contact pressure applied to the contact portion exceeds 630 N / mm ^2. It can be said that this can be reduced.

  As mentioned above, although the Example of this invention was described in detail, this invention is not limited to the said Example, A various change is possible within the range which does not impair the meaning of this invention.

DESCRIPTION OF SYMBOLS 1 Electrical contact pair 11 1st electrical contact 111 1st electroconductive base material 113 1st Ag-Sn alloy layer 114 1st Ag layer 12 2nd electrical contact 121 2nd electroconductive base material 123 2nd Ag-Sn alloy layer 124 2nd Ag layer 13 Contact 2 Connector terminal pair

Claims (5)

A first Ag-Sn alloy layer and a first Ag layer laminated on the surface of the first Ag-Sn alloy layer are provided above the first conductive base material, and the first Ag layer is exposed on the outermost surface. A first electrical contact;
A second Ag-Sn alloy layer and a second Ag layer laminated on the surface of the second Ag-Sn alloy layer are provided above the second conductive base material, and the second Ag layer is exposed on the outermost surface. A second electrical contact;
A contact portion formed by contacting the surface of the first Ag layer in the first electrical contact with the surface of the second Ag layer in the second electrical contact;
A contact pressure applied to the contact portion is 630 N / mm ² or less.   Between the first conductive base material and the first Ag-Sn alloy layer and / or between the second conductive base material and the second Ag-Sn alloy layer, a Ni layer and / or a Ni alloy The electrical contact pair according to claim 1, further comprising a layer.   The electrical contact pair according to claim 1 or 2, wherein the first conductive base material and the second conductive base material are made of copper or a copper alloy, or aluminum or an aluminum alloy.   A connector terminal pair comprising the electrical contact pair according to claim 1.   The first terminal having the first electrical contact and the second terminal having the second electrical contact are included, and the contact portion is formed by fitting the first terminal and the second terminal. The connector terminal pair according to claim 4, wherein the connector terminal pair is formed.

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