阅读说明：本技术 低插入力触头及其制造方法 (Low insertion force contact and method of making same ) 是由 M.K.迈尔斯 于 2020-08-25 设计创作，主要内容包括：一种低插入力触头包括导电基层,其延伸到配合端,该配合端包括配合接口,该配合接口配置为配合电连接至配合触头。银涂层设置在该导电基层上。该银涂层设置在配合端处。硫化银表面层在该银涂层上直接形成固体润滑剂。该硫化银表面层形成薄膜,在配合接口处限定低插入力触头的具有受控的厚度的表面。(A low insertion force contact includes an electrically conductive base layer extending to a mating end that includes a mating interface configured to mate electrically connected to a mating contact. A silver coating is disposed on the conductive base layer. The silver coating is disposed at the mating end. The silver sulfide surface layer forms a solid lubricant directly on the silver coating. The silver sulfide surface layer forms a thin film defining a surface of the low insertion force contact having a controlled thickness at the mating interface.)

1. A low insertion force contact, comprising:

a conductive base layer extending to a mating end, the mating end including a mating interface configured to be matingly electrically connected to a mating contact;

a silver coating disposed on the conductive base layer, the silver coating disposed at the mating end; and

a silver sulfide surface layer forming a solid lubricant directly on the silver coating, the silver sulfide surface layer forming a thin film defining a surface of the low insertion force contact at the mating interface, the thin film having a controlled thickness.

2. The low insertion force contact of claim 1, wherein the silver sulfide surface layer is actively formed directly on the silver coating.

3. The low insertion force contact of claim 1, wherein the silver sulfide surface layer reduces a coefficient of friction of the low insertion force surface compared to a coefficient of friction of the silver coating.

4. The low insertion force contact of claim 1, wherein the silver sulfide surface layer is an additive film formed directly on the silver coating.

5. The low insertion force contact of claim 1, wherein the silver sulfide surface layer has a controlled coloration at the mating interface.

6. The low insertion force contact of claim 1, wherein the silver sulfide surface layer is formed by a non-hazardous chemical treatment of the silver coating.

7. The low insertion force contact of claim 1, wherein the silver sulfide surface layer is a lubricating film on the silver coating.

8. The low insertion force contact of claim 1, wherein the silver sulfide surface layer has a controlled thickness.

9. The low insertion force contact of claim 1, wherein the silver sulfide surface layer is configured to be mated to the mating contact at the mating interface.

10. The low insertion force contact of claim 1, wherein an entire surface area of the mating end of the conductive base layer is covered by the silver sulfide surface layer.

11. The low insertion force contact of claim 1, further comprising a nickel coating between the conductive base layer and the silver coating.

12. The low insertion force contact of claim 1, wherein the conductive base layer is one of a copper base layer or a copper alloy base layer.

13. A low insertion force contact, comprising:

a conductive base layer extending to a mating end, the mating end including a mating interface configured to mate electrically connected to a mating contact, the conductive base layer being a copper base layer or a copper alloy base layer;

a nickel coating disposed directly on the conductive base layer, the nickel coating disposed at the mating end;

a silver coating disposed directly on the nickel coating, the silver coating disposed at the mating end; and

a silver sulfide surface layer disposed directly on the silver coating, the silver sulfide surface layer forming a solid lubricant film that defines a surface of the low insertion force contact at the mating interface.

14. The low insertion force contact of claim 13, wherein the silver sulfide surface layer reduces a coefficient of friction of the low insertion force surface compared to a coefficient of friction of the silver coating.

15. A method of manufacturing a low insertion force contact, the method comprising:

providing an electrically conductive base layer comprising a mating end comprising a mating interface configured to be matingly electrically connected to a mating contact;

applying a silver coating on the conductive base layer at the mating end; and

forming a surface layer of silver sulfide directly on the silver coating to define a thin film of solid lubricant defining a surface of the low insertion force contact at the mating interface, the thin film of solid lubricant having a controlled thickness of silver sulfide material at the mating interface.

16. The method of claim 15, wherein forming the silver sulfide surface layer comprises chemically treating the silver coating using a non-hazardous chemical treatment to form the silver sulfide surface layer on the silver coating.

17. The method of claim 15, wherein forming the silver sulfide surface layer comprises treating the silver coating with a chemical treatment to obtain a uniform colored thin film on the silver coating.

18. The method of claim 15, wherein applying a silver coating comprises plating the silver coating on the conductive base layer.

19. The method of claim 15, wherein forming the surface layer of silver sulfide comprises treating the silver coating in a chemical bath.

20. The method of claim 15, wherein forming the silver sulfide surface layer comprises controlled tarnishing of the silver coating to form the silver sulfide surface layer.

Technical Field

The subject matter herein relates generally to low insertion force contacts.

Background

Contacts are used in a variety of applications. The contacts typically mate with a mating component, such as a circuit board or mating electrical connector at a mating interface. During mating, the contacts may wipe the mating components, and friction between the contacts and the mating components at the mating interface may be problematic. For example, when multiple contacts are mated simultaneously, the friction of each contact can result in high mating forces with the mating component. The coefficient of friction of the material of the contact at the mating interface determines the mating force required to mate the contact(s) with the mating component.

To reduce the mating force, some known systems use a lubricant on the contacts. However, lubricants are messy, can be difficult to apply, and can accumulate dust and debris over time, making the use of lubricants less than ideal. The lubricant may affect the electrical conductivity of the contacts and mating components, making the lubricant unusable in certain applications. After mating, the lubricant may be wiped off, making re-mating of the contacts difficult. Lubricants may not be stable at high temperatures and therefore may not be useful in certain applications.

There remains a need for a low insertion force contact.

Disclosure of Invention

In one embodiment, a low insertion force contact is provided. The low insertion force contact includes an electrically conductive base layer extending to a mating end, the mating end including a mating interface configured to matingly electrically connect to the mating contact. The silver coating is disposed on the conductive base layer. A silver coating is disposed at the mating end. The silver sulfide surface layer forms a solid lubricant directly on the silver coating. The silver sulfide surface layer forms a thin film of controlled thickness at the mating interface.

In another embodiment, a low insertion force contact is provided. The low insertion force contact includes an electrically conductive base layer extending to a mating end, the mating end including a mating interface configured to matingly electrically connect to the mating contact. The conductive base layer is a copper base layer or a copper alloy base layer. The nickel coating is disposed directly on the conductive base layer. A nickel coating is disposed at the mating end. The silver coating is disposed directly on the nickel coating. A silver coating is disposed at the mating end. The silver sulfide surface layer is disposed directly on the silver coating. The silver sulfide surface layer forms a solid lubricant film at the mating interface.

In another embodiment, a method of manufacturing a low insertion force contact is provided. The method includes providing an electrically conductive substrate including a mating end including a mating interface configured to be matingly electrically connected to a mating contact. The method includes applying a silver coating on the conductive base layer at the mating end. The method forms a surface layer of silver sulfide directly on the silver coating to define a thin film of solid lubricant at the mating interface. The solid lubricant film has a controlled thickness of silver sulfide material at the mating interface.

Drawings

Fig. 1 is a schematic diagram of an electrical component having a low insertion force contact according to an exemplary embodiment.

Fig. 2 is a cross-sectional view of a low insertion force contact according to an exemplary embodiment.

Fig. 3 is a cross-sectional view of a low insertion force contact according to an exemplary embodiment.

Fig. 4 is a cross-sectional view of a low insertion force contact according to an exemplary embodiment.

Fig. 5 is a flow chart illustrating a method of manufacturing a low insertion force contact according to an exemplary embodiment.

Detailed Description

Fig. 1 is a schematic diagram of an electrical component 100 having low insertion force contacts 102 according to an exemplary embodiment. The electrical component 100 is configured to mate with a mating electrical component 104 having mating contacts 106. Alternatively, the mating contacts 106 may be low insertion force mating contacts.

In various embodiments, the electrical component 100 is an electrical connector, such as a plug connector, a receptacle connector, a card edge connector, or the like. In other various embodiments, electrical component 100 is a printed circuit board, such as a circuit card. In various embodiments, the mating electrical component 104 is an electrical connector, such as a plug connector, a receptacle connector, a card edge connector, or the like. In other various embodiments, the mating electrical component 104 is a printed circuit board, such as a circuit card.

In various embodiments, the contacts 102 are stamped and formed contacts, such as pins, sockets, guide tabs, spring beams, and the like. In other various embodiments, the contacts 102 are circuit contacts of a printed circuit board, such as circuit pads or circuit traces of a printed circuit board. In various embodiments, the mating contacts 106 are stamped and formed contacts, such as pins, receptacles, guide tabs, spring beams, and the like. In other various embodiments, the contacts 106 are circuit contacts of a circuit board, such as circuit pads or circuit traces of a printed circuit board.

The low insertion force contact 102 has a solid lubricant 110 formed on the surface of the contact 102. For example, the solid lubricant 110 is formed as a thin film at the mating end 112 of the contact 102. In an exemplary embodiment, the solid lubricant 110 is part of the chemical structure of the contact 102. For example, the contact 102 includes a silver layer and the solid lubricant 110 is a silver sulfide surface layer formed as a thin film on the outside of the silver layer. The solid lubricant 110 is an outer layer or surface of the contact 102 and reduces the coefficient of friction of the contact 102 as compared to a contact that does not include the solid lubricant 110 on the surface (e.g., a contact that includes a silver layer on the surface of the contact). The solid lubricant 110 reduces mating friction when mating with the mating contacts 106.

Fig. 2 is a cross-sectional view of a low insertion force contact 102, according to an exemplary embodiment. The contact 102 includes a conductive base layer 120, may include at least one barrier coating 122, 124 disposed on the conductive base layer 120, and includes a silver sulfide surface layer 130 at a surface of the contact 102. In the exemplary embodiment, silver sulfide surface layer 130 is disposed directly on coating 124; however, in other various embodiments, the silver sulfide surface layer 130 may be disposed directly on the conductive base layer 120, such as when the conductive base layer 120 is a silver base layer. The barrier coatings 122, 124 are provided to enhance the performance of the contact 102. For example, the barrier coatings 122, 124 may provide corrosion resistance, improved solderability, improved electrical conductivity, improved thermal performance, such as increasing the operating temperature of the contact 102, and the like. The silver sulfide surface layer 130 forms a solid lubricant 110 for the contact 102, increasing the lubricity of the contact 102. The silver sulfide surface layer 130 reduces the insertion or mating force with the mating contact 106 (shown in fig. 1). The silver sulfide surface layer 130 may enhance the durability of the contact 102.

In an exemplary embodiment, the conductive base layer 120 is a copper base layer or a copper alloy base layer. The conductive base layer 120 may be another metal base layer such as a steel base layer, an aluminum base layer, a silver base layer, etc. The inner coating 122 is a nickel coating. However, in alternative embodiments, the inner coating 122 may be another type of barrier coating other than a nickel coating. The overcoat 124 is a silver coating. The silver sulfide surface layer 130 forms the solid lubricant 110 directly on the silver coating 124. In alternative embodiments, the contacts 102 may include additional layers. In other various embodiments, the contacts 102 may not be provided with a nickel coating 122, but rather have a silver coating 124 provided directly on the conductive base layer 120.

The coatings 122, 124 are disposed at the mating end 112 (shown in figure 1) of the contact 102. Optionally, the contacts 102 may be selectively coated, such as at the mating end 112, with no coating at other portions of the contacts 102. In other various embodiments, other portions than the mating end 112 may be coated. In various embodiments, the entire contact 102 is coated. In various embodiments, the coatings 122, 124 are disposed on the contacts 102 by a coating process or a pre-coating process. In alternative embodiments, the coatings 122, 124 may be provided by other processes.

In an exemplary embodiment, the silver sulfide surface layer 130 is disposed at the mating interface 114 of the contact 102 at the mating end 112. A silver sulfide surface layer 130 may be selectively formed at controlled areas of the coatings 122, 124. In other various embodiments, the silver sulfide surface layer 130 may be formed over the entire coating 124. In various embodiments, the silver sulfide surface layer 130 is selectively formed on the mating end 112, e.g., at the mating interface 114, with other areas of the mating end 112 being free of the silver sulfide surface layer 130. In other various embodiments, the mating end 112 is completely covered by the silver sulfide surface layer 130. In other various embodiments, other portions than the mating end 112 may have a silver sulfide surface layer 130 formed thereon. In various embodiments, the silver sulfide surface layer 130 may be formed over the entire contact 102.

In an exemplary embodiment, the silver sulfide surface layer 130 is actively formed directly on the silver coating 124. To form a surface layer 130 of silver sulfide by converting the surface atoms of the silver coating 124 to silver sulfide. The silver sulfide surface layer 130 is formed, for example, by chemical treatment of the silver coating 124 to form silver sulfide on the surface of the contact 102. The silver coating 124 may be tarnished by a controlled tarnishing process to form a silver sulfide surface layer 130 on the silver coating 124. In the exemplary embodiment, silver sulfide surface layer 130 is formed by a non-hazardous chemical treatment process; however, in alternative embodiments, the silver sulfide surface layer 130 may be formed by other chemical treatment processes. Alternatively, the chemical treatment may be a sulfide-free chemical treatment. The silver sulfide surface layer 130 is formed as a thin film of controlled thickness on the surface of the contact 102. For example, a surface layer of silver sulfide is uniformly and consistently deposited on the silver coating 124. Alternatively, the silver sulfide surface layer 130 may have a constant thickness over the silver coating 124. In an exemplary embodiment, the controlled thickness of the silver sulfide surface layer 130 is contact-functional. The contact function is defined as being sufficient for the intended application of the electrical contact to function to define a mating interface for mating with a mating contact. The silver sulfide surface layer 130 is contact-functional when the silver sulfide surface layer 130 does not cause electrical connection problems between the contact 102 and the mating contact. In various embodiments, the formed silver sulfide surface layer 130 is formed to have a uniform coloration (e.g., within a range of colors) for visual perception. Staining may be in a visible chromatogram, for example from red to purple. Alternatively, the coloring may be uniformly colored in the yellow range, uniformly colored in the green range, uniformly colored in the blue range or uniformly colored in another color range. In an exemplary embodiment, the contacts 102 are treated to achieve a uniform coloration, which corresponds to a uniform thickness of silver sulfide formed on the surface of the contacts 102.

The silver sulfide surface layer 130 is formed by chemically reacting the sulfur-based product with the silver coating 124 to chemically form silver sulfide on the surface of the contact 102. The silver sulfide surface layer 130 may be formed by Physical Vapor Deposition (PVD), Chemical Vapor Deposition (CVD), or other processes. The solid lubricant 110 forms a part of the contact 102. In various embodiments, the silver sulfide surface layer 130 may be chemically bonded to the silver coating 124. Thus, the silver sulfide surface layer 130 is less susceptible to wear and removal than other lubricants (e.g., grease or liquid lubricants) applied to the outer surface of the contact 102. Thus, the durability of the silver sulfide surface layer 130 may be used for multiple compounding cycles (e.g., much more compounding cycles than lubricant is applied). In an exemplary embodiment, the silver sulfide surface layer 130 is conductive, providing an efficient mating interface for the contacts 102. In an exemplary embodiment, the silver sulfide surface layer 130 is displaceable, for example, during contact wiping, to allow electrical connection between the contact 102 and a mating contact.

Fig. 3 is a cross-sectional view of a low insertion force contact 302 according to an exemplary embodiment. The low insertion force contact 302 may be used with the electrical component 100 (shown in fig. 1) in place of the contact 102 (shown in fig. 1).

The contact 302 includes a conductive base layer 320, a silver coating 324 disposed directly on the conductive base layer 320, and a silver sulfide surface layer 330 disposed directly on the silver coating 324. In an exemplary embodiment, the conductive base layer 320 is a copper base layer or a copper alloy base layer. The conductive base layer 320 may be another metal base layer, such as a steel base layer, an aluminum base layer, a silver base layer, and the like. Coating 324 is a silver coating. The silver sulfide surface layer 330 forms a solid lubricant 310 at the surface of the contact 302, increasing the lubricity of the contact 302. The silver sulfide surface layer 330 reduces the insertion or mating force with the mating contact 106 (shown in fig. 1). The coating 324 and the silver sulfide surface layer 330 are disposed at the mating end 312 of the contact 302. In other various embodiments, portions other than the mating end 312 may be coated. In various embodiments, the entire contact 302 is coated.

In an exemplary embodiment, a silver sulfide surface layer 330 is disposed at the mating interface 314 of the contact 302 at the mating end 312. A silver sulfide surface layer 330 may be selectively formed at controlled areas of the coating 324. In other various embodiments, the silver sulfide surface layer 330 may be formed over the entire coating 324 and cover the entire coating 324. In various embodiments, the silver sulfide surface layer 330 is selectively formed on the mating end 312, e.g., at the mating interface 314, with other areas of the mating end 312 being free of the silver sulfide surface layer 330. In other various embodiments, the mating end 312 is completely covered by the silver sulfide surface layer 330. In other various embodiments, portions other than the mating end 312 may have a silver sulfide surface layer 330 formed thereon. In various embodiments, the silver sulfide surface layer 330 may be formed over the entire contact 302.

In the exemplary embodiment, silver sulfide surface layer 330 is actively formed directly on silver coating 324. For example, the silver sulfide surface layer 330 is formed by chemical treatment of the silver coating 324 to form silver sulfide on the surface of the contact 302. The silver coating 324 can be tarnished by a controlled tarnishing process to form a silver sulfide surface layer 330 on the silver coating 324. In the exemplary embodiment, silver sulfide surface layer 330 is formed by a non-hazardous chemical treatment process; however, in alternative embodiments, the silver sulfide surface layer 330 may be formed by other chemical treatment processes. The silver sulfide surface layer 330 is formed as a thin film of controlled thickness on the surface of the contact 302. For example, a surface layer of silver sulfide is uniformly and consistently deposited on the silver coating 324. Optionally, the silver sulfide surface layer 330 has a constant thickness over the silver coating 324. In an exemplary embodiment, the controlled thickness of the silver sulfide surface layer 330 is contact functional. In various embodiments, the formed silver sulfide surface layer 330 is formed to have a uniform coloration (e.g., within a range of colors) for visual perception. In an exemplary embodiment, the contacts 302 are treated to achieve a uniform coloration, which corresponds to a uniform thickness of silver sulfide formed on the surface of the contacts 302.

The silver sulfide surface layer 330 is formed by chemically reacting the sulfur-based product with the silver coating 324 to chemically form silver sulfide on the surface of the contact 302. Thus, the solid lubricant 310 forms a portion of the contact 302. In various embodiments, the silver sulfide surface layer 330 may be chemically bonded to the silver coating 324. Thus, the silver sulfide surface layer 330 is less susceptible to wear and removal than a lubricant (e.g., grease or liquid lubricant) applied to the outer surface of the contact 302. Thus, the durability of the silver sulfide surface layer 330 may be used for multiple mating cycles (e.g., much more mating cycles than lubricant is applied). In an exemplary embodiment, the silver sulfide surface layer 330 is conductive, providing an efficient mating interface for the contacts 302. In an exemplary embodiment, the silver sulfide surface layer 330 is displaceable, for example, during contact wiping, to allow electrical connection between the contact 302 and a mating contact.

Fig. 4 is a cross-sectional view of a low insertion force contact 402 according to an exemplary embodiment. The low insertion force contacts 402 may be used with the electrical component 100 (shown in fig. 1) in place of the contacts 102 (shown in fig. 1).

The contact 402 includes a silver base layer 420 and a silver sulfide surface layer 430 disposed directly on the silver base layer 420. In an exemplary embodiment, the base layer 420 is a silver or silver alloy base layer. The silver sulfide surface layer 430 forms a solid lubricant 410 at the surface of the contact 402, increasing the lubricity of the contact 402. The silver sulfide surface layer 430 reduces the insertion or mating force with the mating contact 106 (shown in fig. 1). In an exemplary embodiment, a silver sulfide surface layer 430 is disposed at the mating interface 414 of the contact 402 at the mating end 412. The silver sulfide surface layer 430 may be selectively formed on the base layer 420 or may be formed on the entire base layer 420 and cover the entire base layer 420.

In an exemplary embodiment, the silver sulfide surface layer 430 is actively formed directly on the silver based layer 420. The silver sulfide surface layer 430 is formed, for example, by chemical treatment of the silver base layer 420 to form silver sulfide on the surface of the contact 402. The silver based layer 420 may be tarnished by a controlled tarnishing process to form a silver sulfide surface layer 430 on the surface. In the exemplary embodiment, silver sulfide surface layer 430 is formed by a non-hazardous chemical treatment process; however, in alternative embodiments, the silver sulfide surface layer 430 may be formed by other chemical treatment processes. The silver sulfide surface layer 430 is formed as a thin film of controlled thickness on the surface of the contact 402. For example, a surface layer of silver sulfide is uniformly and consistently deposited on the silver base layer 420. The silver sulfide surface layer 430 is formed by chemically reacting the sulfur-based product with the silver-based layer 420 to chemically form silver sulfide on the surface of the contact 402.

Fig. 5 is a flow chart illustrating a method 500 of manufacturing a low insertion force contact according to an exemplary embodiment. The method includes the step of providing 500 a conductive base layer. The conductive base layer includes a mating end including a mating interface configured to be matingly electrically connected to the mating contact. The conductive substrate may be a copper substrate or a copper alloy substrate.

The method includes the step of applying 504 a nickel coating on the conductive base layer. The nickel coating may be applied directly on the conductive base layer by plating the nickel coating. However, in alternative embodiments, the nickel coating may be applied by other coating processes other than plating. The nickel coating may be selectively applied to the conductive base layer, for example at the mating end, leaving other portions of the conductive base layer uncoated.

The method 500 includes the step of applying 506 a silver coating over the nickel coating and the conductive base layer. The silver coating may be applied directly on the nickel coating by plating the silver coating. However, in alternative embodiments, the silver coating may be applied by other coating processes besides plating. The silver coating may be selectively applied to the nickel coating and the conductive base layer, for example at the mating end, leaving the other portions uncoated.

The method 500 includes the step of forming 508 a surface layer of silver sulfide directly on the silver coating to define a thin film of solid lubricant at the mating interface. In various embodiments, the silver sulfide surface layer is formed such that the solid lubricant film has a controlled thickness at the mating interface. The solid lubricant thin film may be formed to have a constant thickness. In various embodiments, the silver sulfide surface layer is formed by chemically treating the silver coating with a non-hazardous chemical treatment. The silver sulfide surface layer may be formed by treating the silver coating with a chemical treatment to obtain a uniform colored thin film on the silver coating. The silver sulfide surface layer may be formed by treating the silver coating in a chemical bath. In various embodiments, the silver sulfide surface layer may be formed by controlling tarnishing of the silver coating.

It is to be understood that the above description is intended to be illustrative, and not restrictive. For example, the above-described embodiments (and/or aspects thereof) may be used in combination with each other. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from its scope. The dimensions, material types, orientations of the various parts, and numbers and positions of the various parts described herein are intended to define the parameters of certain embodiments, and are by no means limiting and are merely exemplary embodiments. Many other embodiments and modifications within the spirit and scope of the claims will be apparent to those of ordinary skill in the art upon reading the foregoing description. The scope of the invention should, therefore, be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled. In the appended claims, the terms "including" and "in which" are used as the plain-english equivalents of the respective terms "comprising" and "wherein". Furthermore, in the following claims, the terms "first," "second," and "third," etc. are used merely as labels, and are not intended to impose numerical requirements on their objects. Furthermore, the limitations of the appended claims are not written in a means-plus-function format, and are not intended to be based on 35u.s.c. § 112, sixth paragraph, unless and until such claim limitations explicitly use the phrase "means for … …", then a functional statement, without further structure.