US2968703A - Circuit controller - Google Patents

Description

Jan. 17, 1961 B. F. MEYER EFAL 2,968,703 I CIRCUIT CONTROLLER Original Filed March 13, 1958 2 Sheets-Sheet 1 Jan. 17, 1961 B. F. MEYER EI'AL 2,968,703

cmcuxw CONTROLLER Original Filed March 15, 1958 2 Sheets-Sheet 2 INVENTOR$ Unite tare-s Patent CIRCUIT CONTROLLER Barthold F. Meyer, Tecumseh, Ontario, Canada, and

Nicholas Toruk, Melvindale, Mich, assignors to General Motors Corporation, Detroit, Mich., a corporation of Delaware Original application Mar. 13, 1958, Ser. No. 721,206,

now Patent No. 2,916,566, dated Dec. 8, 1958. Divided and this application Apr. 16, 1959, Ser. No. 806,939

2 Claims. (Cl. 200-6) This invention relates to circuit controllers and more particularly to switch plate assemblies capable of carrying high amperage current without arcing or welding of the switch contacts. This application is a division of our copending application S.N. 721,206, filed March 13, 1958.

In the preferred embodiment of this invention the switch plate assembly generally includes a pair of complementary plate members having complementary pairs of lanced out bent spring arms. The plate members are located in superposed relationship and are intended to be mounted on a switch base of insulating material which also carries the hot lead of the switch and the stationary switch contacts. The lower plate member is made of stainless steel and carries the movable switch contacts on the spring arms thereof, while the upper plate member is made of beryllium copper and has the spring arms thereof in electrical contact with the movable contacts on the spring arms of the lower plate member.

The plate assembly is particularly adapted for use with toggle type switches wherein movement of a switch actuator in one direction closes one of the movable contacts to a complementary stationary contact and movement of the switch actuator in an opposite direction closes the other movable contact to a complementary stationary contact. The spring arms of the plate members act to hold the switch actuator in a neutral position when not operated and to quickly return the actuator to this position after operation thereof.

By making the plate assembly of a lower plate member of stainless steel and an upper plate member of beryllium copper, the plate assembly is capable of carrying high amperage current, in the range of 60 to 75 amperes, without arcing or welding when the switch contacts are opened. The lower plate member of stainless. steel carries the movable contacts and since stainless steel has an extremely high tensile strength, the spring arms thereof provided a very high breaking force and a very quick opening action to the switch so that the movable switch contacts are instantaneously moved out of engagement with the stationary switch contacts when the switch is opened. This quick opening action very effectively prevents any arcing or welding of the movable and stationary switch contacts which often occurs in switch plate assemblies of the spring arm type which do not have the quick opening action provided by the lower plate member of this invention.

Stainless steel will carry electrical current but is a rather poor conductor as compared to most metals commonly used as electrical conductors, such as copper. Beryllium copper is a very good conductor of electrical current and accordingly the use of beryllium copper for the upper plate member provides an excellent current path between the hot lead of the switch and the movable switch contacts which are in electrical contact with the arms of the upper plate member. The lower plate member is also connected to the hot lead so that current can flow from the hot lead to the movable switch contacts through both plate members.

Thus, the switch plate assembly of this invention has several unique and distinct features. The plate assembly can carry high amperage current without arcing or welding of the switch contacts and yet be capable of supplying the necessary current to the electrical device to be controlled by the switch. Additionally, since stainless steel has a very high tensile strength, as also does beryllium copper, the switch arms can operate through an extremely high number of cycles without fatigue failure and without decreasing the quick opening action of the plate assembly. Further, the pairs of spring arms cooperate to hold the switch actuator in a neutral position when not operated and to quickly return the actuator to neutral position after operation thereof.

These and other features of this invention will be readily apparent from the following specification and drawings, wherein:

Figure 1 is a plan view of an electric switch assembly embodying a switch plate assembly according to this invention;

Figure 2 is an enlarged view partially in section taken along the plane indicated by line 2--2 of Figure 1;

Figure 3 is an enlarged sectional view taken along the plane indicated by line 3-3 of Figure 1;

Figure 4 is an enlarged sectional view taken along the plane indicated by line 4-4 of Figure 1;

Figure 5 is a view partially in section taken along the plane indicated by line 55 of Figure 3; and

Figure 6 is a perspective exploded view.

Referring now to the drawings, the electric switch assembly 10 includes an outer escutcheon plate 12 and an inner generally rectangularly shaped depending housing 14. As can be best seen in Figure 1 of the drawings, the escutcheon plate includes a center cruciform shaped aperture 16 and a pair of generally square shaped apertures 18 to either side thereof, with each of the apertures opening to the housing 14. A switch base 20 of insulating material fits within housing 14 and is secured thereto by means of four angular spring clips 22. One leg of each clip fits within a depression 24 in the switch base and the other leg of the clip fits within a groove 26 in a locating lug 28 of the base and is provided with a lanced tab 30 engageable within an opening 32 in the adjacent wall of housing 14. The switch base is further provided with two longitudinally spaced upright ribs 34, each of which engages a pin 36 adjacent one end thereof to hold the pin within a circular shaped groove 38 provided in the end of a depending rib 40 of escutcheon plate 12 to one side of each of the apertures 18 therein. The other end of each of the pins 36 fits within a circular shaped groove 42 provided'in the lower wall of escutcheon plate 12 to the other side of each of the apertures 18 therein and is held within the groove by the locating lugs 28 in the end walls of the switch base 20.

The switch assembly 10 includes three individual switches, two of the switches 44 being the same and being disposed to either side of the center switch 45. Each of the switches 44 includes a switch actuator 46 rotatably mounted on each of the pins 36 and swingable relative thereto within the apertures 18. The switch actuator 50 of switch 45 is of molded nylon and includes a lower ball shaped end 52 of spherical shape which seats within a spherical seat 54 provided on the inner end of the walls defining the aperture 16. The ball end 52 of switch actuator 50 further includes a central rib 56, and the ball end is angularly cut away at each side of the rib to provide pairs of angularly disposed edges 58, each pair providing a junction rib 60 extending laterally from a side of the rib 56.

Rib 56 is received within a slot 62 provided in the center plate portion 63 of a molded nylon switch actuating member 64, with the ribs 60 being located transversely of the slot and engageable with the switch actuating member to either side of the slot. The switch actuating member further includes generally U-shaped integral bar extensions 66, the end bars of which are apertured at 70. In addition, the sides of the center plate portion 63 are provided with bearing grooves 72. As best shown in Figures 2 and 5 of the drawings, the pins 36 extend through the apertures 70 and are received within the bearing grooves 72 in order to rotatably mount the switch actuating member 64 within the switch housing 14 for rotational movement thereof about the same axis as the axis of rotation of the switch actuators 46. The switch actuators 46 are rotatable about the pins 36 independently of any rotational movement of the switch actuating member 64 and are located within the extensions 66.

As best shown in Figures 3 and 6 of the drawings, a pair of stamped metal switch plates 74 and 76 according to this invention fit within the switch base 20 and are riveted thereto by an elongated rivet 78 which also furnishes the hot lead to the switch. The plate 74 is of stainless steel and the plate 7 6 is of beryllium copper. It will be noted from Figure 6 that the plate 74 includes three pairs of lanced out upwardly bent arms 80, 81, and 82 with each arm mounting a contact button 84 normally open to a fixed contact 66 secured to the switch base 20. The plate 76 also includes three pairs of lanced out upwardly bent arms 67, S8, and 39 which are complementary to the arms 86, 8t, and 82, respectively, and normally engage the contact buttons 84. The complementary pairs of arms 80, 87 and 82, 89 are the same and extend generally transversely of plates 74 and 76 and terminate to either side of the center line thereof which is generally coplanar with the aligned axes of pins 36. The complementary pairs of arms 31, 38 extend generally transversely and longitudinally of the plates 74 and 76 and terminate at the center line thereof so that the buttons 84 of arms 81 are located beneath and in alignment with the slot 62 of the switch actuating member 50.

As best shown in Figure 3 of the drawings, each complementary pair of arms til), 87, normally engages a portion 96 of the one actuator 46 to either side of the pivotal axis thereof as defined by the pin 36 to hold the actuator in a neutral position. In addition, it will be noted that each complementary pair of arms 80, 87 also engage a bar 92 of the extension 66 of the switch actuating member to also hold the switch actuating member in a neutral position. Since the complementary pairs of arms 82, 89, are the same as the complementary pairs of arms 80, 87, they will function in the same manner to hold the other actuator 46 in a neutral position and cooperate with arms 80, 87 in holding the switch actuating member 64 in a neutral position. This arrangement of the complementary pairs of arms and switch actuators is disclosed and claimed in Serial No. 665,956, Meyer, filed June 17, 1957, assigned to the assignee of this invention, and reference may be had thereto for a more complete description.

The center pairs of complementary arms 81, 88 terminate below the slot 62 and in alignment therewith, as previously mentioned, and the arms 68 are normally in engagement with the rib 56 of the switch actuator 50 to hold the actuator in a neutral position It is believed obvious that if either of the switch actuators 46 is moved either upwardly or downwardly as viewed in Figures 1 and 3, the switch actuators will close a respective pair of contacts 34 and 86. During this movement it can be seen that the switch actuating member 64 will remain in position without any movement. Likewise it can be seen that if the switch actuator 50 is moved either to the left or to the right as viewed in Figure 2, the actuator will pivot about an axis defined by the line of engagement of the ribs 66 with the switch actuating member 64 to close a respective pair of contacts 84 and 86 without movement of member 64 since rib 56 will move within slot 62 and the ribs 60 of the switch actuator engage the member 64 at each side of the pivotal axis thereof. In order to insure engagement of a contact 84 with a respective contact 86, the actuator 50 includes an integral square shaped lug portion 98 which is received within either of the oppositely disposed legs 10%) of the cruciform shaped aperture 16. Thus it can be seen that each of the switch actuators 46 and the switch actuator 50 can be selectively moved to close the respective switches 44 and 45 without any movement of the switch actuating member 64-.

Assuming now that it is desired to close respective contacts 84 of the switches 45 to their respective contacts 86. Normally this would be done by moving both of the switch actuators 46 in the same direction, either simultaneously upwardly or simultaneously downwardly as viewed in Figures 1 and 3. However, all that the operator need do is move the switch actuator 50 either up- Wardly or downwardly as viewed in Figures 1 and 4 with this movement being guided by the lug 98 fitting within either of the oppositely disposed legs 102 of aperture 16. If the switch actuator 50 is moved upwardly, then it will swing the switch actuating member 64 counterclockwise about the pins 36, as viewed in Figure 3, to simultaneously close the one or upper set of contacts 84 of both switches 45 to their respective contacts 86 due to the engagement of the bars 92 of the switch actuating member with the arms 87 and 89 of the switch plate 76. Likewise, movement of the switch actuator 50 in a downward direction as viewed in Figures 1 and 4 Will swing the switch actuating member 64 in a clockwise direction about the pins 36, as viewed in Figure 3, to simultaneously close the other or lower set of contacts 84 to their respective contacts 86. During this up and down movement of the switch actuating member 50, the center pair of arms 88 of plate 76 are not depressed, since the rib 56 of actuator 50 merely slides relative to the arms. Thus, the switch actuating member 5'9 is adapted to operate the switch 45 when moved in one direction of movement and is also adapted to operate the switches 44 when moved in a direction normal to the one direction of movement without movement of the actuators 46 and without operating the switch 45.

If a switch assembly of this type is used as a seat con trol switch for a power operated vehicle seat which is selectively adjustable in both horizontal and vertical directions, the switches 44 may be adapted to respectively control vertical movement or" the front and rear portions of the seat, and the switch 45 may be adapted to control horizontal movement of the seat when the switch actuator 59 thereof is moved either to the left or to the right as viewed in Figure l and may also be adapted to control simultaneous vertical movement of the front and rear portions of the seat when the switch actuator 50 thereof is moved either upwardly or downwardly as viewed 1n Figure 1 to simultaneously operate the switches 44 as previously described.

It will also be remembered that the switch plate 74 is of stainless steel and the switch plate 76 is of beryllium copper suitable alloys for the switch plate 74 are those containing from 18 to 22% chromium and from 8 to 12% nickel, in addition to small amounts of manganese, the commonly used 18-8 chrome-nickel austenitic stainless steel being a specific example. Suitable alloys for the switch plate 76 are those containing from 1 to 5% beryllium, small amounts of either cobalt or nickel, and the remainder copper, a specific example being an alloy containing 2% beryllium, 25% cobalt or 35% nickel, and the remainder copper.

A switch plate assembly according to this invention provides a greatly improved switch contact arrangement. By mounting the moving contacts 84 of the switches on the upwardly bent arms of the stainless steel switch plate, the life and the current carrying ability of the switch are greatly improved. The arms of the stainless steel switch plate have inherent spring characteristics so that when the switch is opened, the arms instantaneously move the moving contacts 84 out of engagement with the fixed contacts 86 to thereby prevent arcing or welding of the contacts. Additionally, the high tensile strength of stainless steel provides a very high breaking force between the switch contacts so that the arms of the stainless steel switch plate have sufiicient force to overcome any slight welding of the contacts and instantaneously move the contacts apart. Although the stainless steel switch plate 74 is connected to the hot lead 78 of the switch, this plate does not furnish a particularly ellicient current path from the hot lead to the moving contacts. The arms of the beryllium copper switch plate engage the contacts 84 and thereby provide an efficient current path from the hot lead 78 to the moving contacts. A switch embodying a switch plate assembly according to this invention has been built and tested and has successfully operated for 10,000 cycles with 60 ampere, 14 volt D.'C. current.

It will also be understood, of course, that although the switch plates 74 and 76 are shown as being separate from each other, the two plates could very easily be unitary with each other in the form of a laminar plate. In a construction such as this, the contacts 84 would be secured to the spring arms of the laminar plate.

It will also be understood that although the switch plate assembly of this invention has been described in conjunction with a particular type of electric switch, it will have many other and varied uses in other types of electric switches. Additionally, although the plate members have been shown and described as including three pairs of complementary arms, they may also be used with equal success with any number of pairs of complementary arms as well.

Thus this invention provides an improved electric switch plate assembly.

We claim:

1. In a circuit controller, the combination comprising, a switch base, a stationary switch contact secured to said base, a pair of upper and lower switch plate mem bers secured to said base, each member including a complementary integral bent spring arm, the lower of said plate members being of stainless steel, and the upper of said plate members being of beryllium copper, a movable switch contact secured to the arm of said stainless steel plate member and being in Sliding electrical contact with the complementary arm of said beryllium copper plate member, said movable switch contact being normally held in spaced relationship to said fixed contact by said arm of said stainless steel plate member, and a source of electrical energy connected to said stainless steel plate member and to said beryllium copper plate member, the main current path from said source of electrical energy to said movable switch contact being through said beryllium copper plate member and the spring arm thereof in sliding electrical contact with said movable switch contact.

2. A circuit controller comprising, a switch housing, an insulating base secured to said housing, a switch actuator pivotally mounted on said housing, a stationary switch contact secured to said base, a pair of upper and lower switch plate members secured to said base, each member including complementary pairs of integral upwardly bent spring arms extending oppositely to each other across the pivotal axis of said actuator, the lower of said plate members being of stainless steel, and the upper of said plate members being of beryllium copper, a movable switch contact secured to each arm of said stainless steel plate member adjacent the free end thereof and being in sliding electrical contact with the complementary arm of said beryllium copper plate member, said movable switch contacts being normally held in spaced relationship to said fixed contact by said arms of said stainless steel plate member, the free ends of the arms of said beryllium copper plate member being engageable with said switch actuator to either side of the pivotal axis thereof and generally opposite the sliding contact of said arms with said movable switch contacts to maintain said actuator in neutral position, and a source of electrical energy connected to said stainless steel plate member and to said beryllium copper plate member, the main current path from said source of electrical energy to said movable switch contact being through said berylhum copper plate member and the spring arm thereof in sliding electrical contact with said movable switch contact.

References Cited in the file of this patent UNITED STATES PATENTS 2,081,813 Hermann May 25, 1937 2,681,963 Fahnoe June 22, 1954 2,815,501 Benson Dec. 3, 1957 FOREIGN PATENTS 669,969 Great Britain Apr. 9, 1952

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