US1907932A - Process of manufacturing electrical contact members - Google Patents
Process of manufacturing electrical contact members Download PDFInfo
- Publication number
- US1907932A US1907932A US497784A US49778430A US1907932A US 1907932 A US1907932 A US 1907932A US 497784 A US497784 A US 497784A US 49778430 A US49778430 A US 49778430A US 1907932 A US1907932 A US 1907932A
- Authority
- US
- United States
- Prior art keywords
- contact
- metal
- base metal
- welding
- strip
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- 238000000034 method Methods 0.000 title description 11
- 238000004519 manufacturing process Methods 0.000 title description 9
- 239000010953 base metal Substances 0.000 description 54
- 239000002184 metal Substances 0.000 description 49
- 229910052751 metal Inorganic materials 0.000 description 49
- 238000003466 welding Methods 0.000 description 28
- 239000002131 composite material Substances 0.000 description 8
- 238000002844 melting Methods 0.000 description 7
- 230000008018 melting Effects 0.000 description 7
- 150000002739 metals Chemical class 0.000 description 6
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 4
- 239000010970 precious metal Substances 0.000 description 4
- 238000005520 cutting process Methods 0.000 description 3
- KDLHZDBZIXYQEI-UHFFFAOYSA-N Palladium Chemical compound [Pd] KDLHZDBZIXYQEI-UHFFFAOYSA-N 0.000 description 2
- 230000007797 corrosion Effects 0.000 description 2
- 238000005260 corrosion Methods 0.000 description 2
- 230000004927 fusion Effects 0.000 description 2
- 229910052759 nickel Inorganic materials 0.000 description 2
- MOFOBJHOKRNACT-UHFFFAOYSA-N nickel silver Chemical compound [Ni].[Ag] MOFOBJHOKRNACT-UHFFFAOYSA-N 0.000 description 2
- 239000010956 nickel silver Substances 0.000 description 2
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Chemical compound [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 description 2
- 230000006978 adaptation Effects 0.000 description 1
- 239000000956 alloy Substances 0.000 description 1
- 229910045601 alloy Inorganic materials 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- PCHJSUWPFVWCPO-UHFFFAOYSA-N gold Chemical compound [Au] PCHJSUWPFVWCPO-UHFFFAOYSA-N 0.000 description 1
- 229910052737 gold Inorganic materials 0.000 description 1
- 239000010931 gold Substances 0.000 description 1
- 239000011872 intimate mixture Substances 0.000 description 1
- 238000004021 metal welding Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 229910052763 palladium Inorganic materials 0.000 description 1
- 229910052697 platinum Inorganic materials 0.000 description 1
Images
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
- H01H11/00—Apparatus or processes specially adapted for the manufacture of electric switches
- H01H11/04—Apparatus or processes specially adapted for the manufacture of electric switches of switch contacts
- H01H11/041—Apparatus or processes specially adapted for the manufacture of electric switches of switch contacts by bonding of a contact marking face to a contact body portion
- H01H11/043—Apparatus or processes specially adapted for the manufacture of electric switches of switch contacts by bonding of a contact marking face to a contact body portion by resistance welding
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
- H01H1/00—Contacts
- H01H1/12—Contacts characterised by the manner in which co-operating contacts engage
- H01H1/14—Contacts characterised by the manner in which co-operating contacts engage by abutting
- H01H2001/145—Contacts characterised by the manner in which co-operating contacts engage by abutting by crossing each other, the cooperating contacts each having a contact making ridge perpendicular to each other
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T29/00—Metal working
- Y10T29/49—Method of mechanical manufacture
- Y10T29/49002—Electrical device making
- Y10T29/49117—Conductor or circuit manufacturing
- Y10T29/49204—Contact or terminal manufacturing
- Y10T29/49208—Contact or terminal manufacturing by assembling plural parts
- Y10T29/4921—Contact or terminal manufacturing by assembling plural parts with bonding
- Y10T29/49211—Contact or terminal manufacturing by assembling plural parts with bonding of fused material
Definitions
- This invention relates to aprocess of manmetal with the sections of contact metal se ufacturing electrical contact members, and
- the invention contemplates a process of manufacturing bimetallic contact elements wherein contact metal, suchas platinum, palladium or alloys of either of these metals with gold or other of the precious metals particularly adaptable for electrical contact elements is formed into a substantially cylindrical strip or wire having a ridge longitudinally thereof, may be cut to predetermined lengths, and then welded to a base metal such as nickel silver, pure nickel or other metals having a high degree of resistance to corrosion at spaced intervals, which is formed in a strip or ribbon of substantially rectangular cross-section,
- FIG. 2 is a plan view of the ribbon of base tion of the contact elements thereon in their completed form.
- the numeral 6 indicates a strip or wire of precious metal of the type commonly used for contact metal in the contacts of electrical apparatus and is formed to a substantially circular cross-section having a rounded ridge 8 extending longitudinally thereof.
- the wire 6 of contact metal After the wire 6 of contact metal has been formed to the above described shape, it is cut into predetermined lengths and combined, as shown in Fig. 2, with a strip 10 of base metal which may be nickel silver, pure nickel or other metals which have a high degree of resistance to corrosion, being positioned upon the base metal at spaced intervals with the ridge 8 of the wire 6 engaging the flat upper surface of the strip 10 which is substantially rectangular in cross-section and which has depending ridges 12 extending longitudinally thereof.
- the wire 6 of contact metal and the strip 10 of base metal are shownin Fig. 1 engaged by electrodes '14 and. 16 electrically connected with a source of current supply 15 so that an electrical welding circuit may be completed through the electrode 14:, the wire 6 of contact metal and the strip 10 of base metal to the electrode 16 to weld the contact metal to the base metal.
- the electrode 14 engages that portion of the wire 6 away from the ridge 8, and the electrode 16 engages the under side of the base metal.
- a welding current passing through the wire of contact metal and the strip of base metal will encounter its greatest resistance at the line of engagement of the ridge 8 with the flat upper surface of the strip 10, and due to the formation of the wire 6 the electrode 14 engages therewith over a comparatively large area, whereas the ridge 8 provides only a small area of contact with the base metal, thereby resulting in a concentration of the welding current along the line of contact.
- This concentration of the welding current will cause fusion of the contact metal and the base metal strip 10 and will prevent the base metal from sticking to the electrode 16 or from burning due to the fact that the relatively large crosssection of the base metal provides a chilling effect at the point of contact with the precious metal and causes the ridge of the contact metal which has a relatively small crosssection to rise to the melting temperature at'approximately the same time that the base metal is raised to its melting temperature, thus permitting an intimate mixture of the molten metals and a strong weld.
- the composite contact elements thus formed may be out along the lines 18, 20, and 22 to provide separate composite contact elements 23 which may be attached to contact springs 24 of electrical apparatus.
- a composite contact element 23 cut from the strip as just described may be positioned at an angle of approximately 45 upon a flat surface of an electrical contact spring 24 with the ridges 12 engaging the upper surface of the spring.
- a welding electrode 26 may be engaged with the flat upper surface of the strip of base metal 10 and a welding electrode 28 having a polarity opposite to that of the welding electrode 26 may be engaged with the underside of the contact spring to complete a weldng circuit which may be the same as shown 1n Fig. 1 through the electrode 28, contact spring 24, base metal strip 10 to the welding electrode 26.
- This welding circuit may be maintained until the downwardly extending ridges 12 of the strip 10 have fused with the upper surface of the contact "spring 24 to secure the composite contact element to the spring 24 as shown in Fig. 4.
- The'provision y of the downwardly extending ridges 12 on the strip 10 of the base metal provides concentration points for the welding current applied to the base metal and the electrical contact spring so that despite the difference in the fusing temperatures of the metal of the strip 12 and of the contact spring, the fusion of these metals upon application of the welding current will occur substantially simultaneously, thereby preventing sticking of the metals to the welding electrodes or burning of the base metal and providing a good welded union between the two parts.
- Fig. 5 wherein a pair of springs are shown having positioned near the ends thereof and upon opposing surfaces thereof, a pair of cooperating contact elements.
- the contact elements are positioned diagonally of the springs and the element carried by one springis angularly disposed with respect to the cooperating contact element carried by the other or companion spring.
- bimetallic contact elements which includes forming a ribbon of base metal to a substantially rectangular shape having depending ridges on one portion thereof, forming a contact ele-' ment of a higher melting point metal with a depending ridge adapted to engage the base metal, combining the base metal and contact metal with the depending ridges of the base metal on the side thereof away from the contact metal, welding the contact metal to the base metal, engaging the depending ridges of the base metal with a contact spring and welding the base metal to the contact spring.
- bimetallic contact elements which includes forming a base metal with a depending ridge, forming a contact element of a higher melting, point metal having a substantially cylindrical cross-section with a protuberance on its periphery, contacting the base metal and contact metal with the protuberance of the lic contact elements which includes forming a ribbon of base metal of predetermined dinnensions, forming a contact element of a higher melting point metal and having a substantially cylindrical cross-section with a protuberance on its periphery, contacting the base metal and contact metal with the protuberance of the contact metal engaging the base metal, applying electrodes to the base metal and that portion of the contact metal farthest removed from the protuberance, ap-
- bimetallic contact elements which includes forming a ribbon of base metal to a substantially rectangular cross-sectional shape having ridges on one surface thereof, forming a wire of contact metal of ahigher melting point metal metal with the rounded ridge formed on the contact metal engaging-the surface of the base metal away from the ridges formed thereon, applying welding electrodes to' the v base metal and to the surface of the lengths of contact metal away from the ridge thereon, applying a welding current to the electrodes to weld the contact metal to the base metal, cutting the base metal with the contact metal welded. thereto to predetermined lengths, positioning the length of base metal
Description
FYLJGH May 9 193.30
PROCESS OF MANUFACTURING ELECTRICAL CONTACT MEMBERS Filed Nov. 24, 1930 Patented May 9, v 1933 UNITED STATES Parent EMERSON" PU'GE, 0F DOWNERS GROVE, ILLINQIS, ASSIGNUR T63 WESTERN EEECTRIG COMPANY, INCORPORATED, 015 NEW YORK, N. Y., i-l CGRPORATIQN OF NEW YORK PROCESSOF MANUFACTURING FLJECTRIGAL CONTACT TQEMBERS Application filed November 24, 1930. Serial No. 497,784,
This invention relates to aprocess of manmetal with the sections of contact metal se ufacturing electrical contact members, and
more particularly to a process of manufacturing bimetallic contact elements.
It is an object of the present invention to provide an efficient process of manufacturmg composite bimetallic, electrical contacts, utilizing a minimum amount of contact metal.
In accordance with one embodiment, the invention contemplates a process of manufacturing bimetallic contact elements wherein contact metal, suchas platinum, palladium or alloys of either of these metals with gold or other of the precious metals particularly adaptable for electrical contact elements is formed into a substantially cylindrical strip or wire having a ridge longitudinally thereof, may be cut to predetermined lengths, and then welded to a base metal such as nickel silver, pure nickel or other metals having a high degree of resistance to corrosion at spaced intervals, which is formed in a strip or ribbon of substantially rectangular cross-section,
v and which is provided with two ridges extending longitudinally thereof. By having the longitudinal ridge on the wire of contact -metal, the current applied for welding purposes to the elements making up the composite contact is localized at the point of contact between the contact wire and the ribbon of base metal thereby insuring a strong welded union and avoiding the possibility of damaging the contact wire or base metal by the heat of the current required to form the weld. A
- composite contact element thus formed may then be secured to a contact spring of electrical apparatus by welding the base metal welding operation Fig. 2 is a plan view of the ribbon of base tion of the contact elements thereon in their completed form.
Referring now to the drawing wherein the same reference characters designate like parts throughout the several views, the numeral 6 indicates a strip or wire of precious metal of the type commonly used for contact metal in the contacts of electrical apparatus and is formed to a substantially circular cross-section having a rounded ridge 8 extending longitudinally thereof. After the wire 6 of contact metal has been formed to the above described shape, it is cut into predetermined lengths and combined, as shown in Fig. 2, with a strip 10 of base metal which may be nickel silver, pure nickel or other metals which have a high degree of resistance to corrosion, being positioned upon the base metal at spaced intervals with the ridge 8 of the wire 6 engaging the flat upper surface of the strip 10 which is substantially rectangular in cross-section and which has depending ridges 12 extending longitudinally thereof.
The wire 6 of contact metal and the strip 10 of base metal are shownin Fig. 1 engaged by electrodes '14 and. 16 electrically connected with a source of current supply 15 so that an electrical welding circuit may be completed through the electrode 14:, the wire 6 of contact metal and the strip 10 of base metal to the electrode 16 to weld the contact metal to the base metal. The electrode 14 engages that portion of the wire 6 away from the ridge 8, and the electrode 16 engages the under side of the base metal. Therefore, a welding current passing through the wire of contact metal and the strip of base metal will encounter its greatest resistance at the line of engagement of the ridge 8 with the flat upper surface of the strip 10, and due to the formation of the wire 6 the electrode 14 engages therewith over a comparatively large area, whereas the ridge 8 provides only a small area of contact with the base metal, thereby resulting in a concentration of the welding current along the line of contact. This concentration of the welding current will cause fusion of the contact metal and the base metal strip 10 and will prevent the base metal from sticking to the electrode 16 or from burning due to the fact that the relatively large crosssection of the base metal provides a chilling effect at the point of contact with the precious metal and causes the ridge of the contact metal which has a relatively small crosssection to rise to the melting temperature at'approximately the same time that the base metal is raised to its melting temperature, thus permitting an intimate mixture of the molten metals and a strong weld.
After the wire 6 of contact metal has been formed to the shape .shown in Fig. 1, cut to predetermined lengths and welded to the strip 10 of base metal at intervals along the length thereof, as shown in Fig. 2, in the manner described hereinbefore, the composite contact elements thus formed may be out along the lines 18, 20, and 22 to provide separate composite contact elements 23 which may be attached to contact springs 24 of electrical apparatus.
Referring now to Fig. 3, a composite contact element 23 cut from the strip as just described may be positioned at an angle of approximately 45 upon a flat surface of an electrical contact spring 24 with the ridges 12 engaging the upper surface of the spring. A welding electrode 26 may be engaged with the flat upper surface of the strip of base metal 10 and a welding electrode 28 having a polarity opposite to that of the welding electrode 26 may be engaged with the underside of the contact spring to complete a weldng circuit which may be the same as shown 1n Fig. 1 through the electrode 28, contact spring 24, base metal strip 10 to the welding electrode 26. This welding circuit may be maintained until the downwardly extending ridges 12 of the strip 10 have fused with the upper surface of the contact "spring 24 to secure the composite contact element to the spring 24 as shown in Fig. 4. The'provision y of the downwardly extending ridges 12 on the strip 10 of the base metal provides concentration points for the welding current applied to the base metal and the electrical contact spring so that despite the difference in the fusing temperatures of the metal of the strip 12 and of the contact spring, the fusion of these metals upon application of the welding current will occur substantially simultaneously, thereby preventing sticking of the metals to the welding electrodes or burning of the base metal and providing a good welded union between the two parts.
Contact springs formed in accordance with the above outlined method may be combined as shown in Fig. 5 wherein a pair of springs are shown having positioned near the ends thereof and upon opposing surfaces thereof, a pair of cooperating contact elements. The contact elements are positioned diagonally of the springs and the element carried by one springis angularly disposed with respect to the cooperating contact element carried by the other or companion spring. By having this arrangement a cross contact is effected between the adjacent surfaces of the two contact elements in response to movement of one of the springs, and it will be apparent that less precious metal is necessary than would be required in the ordinary type of contact element since a comparatively large area is provided for use as contacting surface and even if the associated springs 24 are not exactly aligned a contact will be made between the contact elements upon operation of the springs.
Although a specific embodiment of the invention has been described hereinbefore, it will be understood that modifications and adaptations of the method may be made without departing from the scope of the invention which is to be limited only by the appended claims.
What is claimed isi 1. The process of manufacturing bimetallic contact elements which includes forming a base metal to predetermined dimensions, forming a contact element of a higher melting point metal with a depending rounded ridge adapted to engage the base metal, welding the contact metal to the base metal and welding the base metal to a contact spring.
2. The process of manufacturing bimetallic contact elements which includes forming a ribbon of base metal to a substantially rectangular shape having depending ridges on one portion thereof, forming a contact ele-' ment of a higher melting point metal with a depending ridge adapted to engage the base metal, combining the base metal and contact metal with the depending ridges of the base metal on the side thereof away from the contact metal, welding the contact metal to the base metal, engaging the depending ridges of the base metal with a contact spring and welding the base metal to the contact spring.
3. The process of manufacturing bimetallic contact elements which includes forming a base metal with a depending ridge, forming a contact element of a higher melting, point metal having a substantially cylindrical cross-section with a protuberance on its periphery, contacting the base metal and contact metal with the protuberance of the lic contact elements which includes forming a ribbon of base metal of predetermined dinnensions, forming a contact element of a higher melting point metal and having a substantially cylindrical cross-section with a protuberance on its periphery, contacting the base metal and contact metal with the protuberance of the contact metal engaging the base metal, applying electrodes to the base metal and that portion of the contact metal farthest removed from the protuberance, ap-
With a section of contact metal welded thereto in a position with the ridges engaging a contact spring, applying a welding electrode to the upper surface of the composite base and contact metal, applying another welding electrode to the underside of the contact spring, and completing an electrical circuit through the welding electrodes to weld the combined contact and base metal to the contact spring. K
In witness whereof, I hereunto subscribe my name this 15th day of November A. D.,
EMERSON PUGH.
plying a welding current to the electrodes to I fuse thebase metal and. contact metal at the point Where the protuberance of the contact a metal engages .the' base metal and welding \face thereof, cutting the contact met-a1 into predetermined lengths, positioning the contact metal at intervals along the ribbon of base metal with the ridge of the contact metal engaging the surface of the base metal opposite to the surface of the base metal on which the ridges are formed, applying welding electrodes to the base metal and to the surface of contact metal removed from the rounded ridge, applying a welding current to the electrodes to weld the contact metal to the base metal, cutting the/base metal with the contact metal welded thereto to predetermined lengths, and welding the base metal to electrical contact springs.
6. The process of manufacturing bimetallic contact elements which includes forming a ribbon of base metal to a substantially rectangular cross-sectional shape having ridges on one surface thereof, forming a wire of contact metal of ahigher melting point metal metal with the rounded ridge formed on the contact metal engaging-the surface of the base metal away from the ridges formed thereon, applying welding electrodes to' the v base metal and to the surface of the lengths of contact metal away from the ridge thereon, applying a welding current to the electrodes to weld the contact metal to the base metal, cutting the base metal with the contact metal welded. thereto to predetermined lengths, positioning the length of base metal
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US497784A US1907932A (en) | 1930-11-24 | 1930-11-24 | Process of manufacturing electrical contact members |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US497784A US1907932A (en) | 1930-11-24 | 1930-11-24 | Process of manufacturing electrical contact members |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| US1907932A true US1907932A (en) | 1933-05-09 |
Family
ID=23978294
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US497784A Expired - Lifetime US1907932A (en) | 1930-11-24 | 1930-11-24 | Process of manufacturing electrical contact members |
Country Status (1)
| Country | Link |
|---|---|
| US (1) | US1907932A (en) |
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2433687A (en) * | 1943-09-27 | 1947-12-30 | Metals & Controls Corp | Electrical contact |
| US2629791A (en) * | 1951-06-16 | 1953-02-24 | Tourneau Robert G Le | Snap switch |
| US2760017A (en) * | 1954-05-10 | 1956-08-21 | Allis Chalmers Mfg Co | Tap changer having cylinder to cylinder contact |
| US2831913A (en) * | 1951-04-30 | 1958-04-22 | Wagner Electric Corp | Transformer case grounding pad |
| US2833897A (en) * | 1953-10-29 | 1958-05-06 | Fed Electric Prod Co | Means to minimize fusing of circuit breaker contacts |
| US2922855A (en) * | 1955-01-31 | 1960-01-26 | Giannini Controls Corp | Magnetic switch device |
| US3042474A (en) * | 1962-07-03 | Vern m | ||
| US3082309A (en) * | 1959-08-21 | 1963-03-19 | Bryant Electric Co | Wiring device for controlling circuit continuity |
| US3221969A (en) * | 1963-10-16 | 1965-12-07 | Western Electric Co | Apparatus for fabricating a piece part having a metallic bit secured thereto |
-
1930
- 1930-11-24 US US497784A patent/US1907932A/en not_active Expired - Lifetime
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3042474A (en) * | 1962-07-03 | Vern m | ||
| US2433687A (en) * | 1943-09-27 | 1947-12-30 | Metals & Controls Corp | Electrical contact |
| US2831913A (en) * | 1951-04-30 | 1958-04-22 | Wagner Electric Corp | Transformer case grounding pad |
| US2629791A (en) * | 1951-06-16 | 1953-02-24 | Tourneau Robert G Le | Snap switch |
| US2833897A (en) * | 1953-10-29 | 1958-05-06 | Fed Electric Prod Co | Means to minimize fusing of circuit breaker contacts |
| US2760017A (en) * | 1954-05-10 | 1956-08-21 | Allis Chalmers Mfg Co | Tap changer having cylinder to cylinder contact |
| US2922855A (en) * | 1955-01-31 | 1960-01-26 | Giannini Controls Corp | Magnetic switch device |
| US3082309A (en) * | 1959-08-21 | 1963-03-19 | Bryant Electric Co | Wiring device for controlling circuit continuity |
| US3221969A (en) * | 1963-10-16 | 1965-12-07 | Western Electric Co | Apparatus for fabricating a piece part having a metallic bit secured thereto |
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