US2958752A

US2958752A - Push button switch

Info

Publication number: US2958752A
Application number: US719365A
Authority: US
Inventors: John H Horman
Original assignee: Allied Control Co Inc
Current assignee: Allied Control Co Inc
Priority date: 1958-03-05
Filing date: 1958-03-05
Publication date: 1960-11-01
Anticipated expiration: 1977-11-01
Also published as: GB829734A

Description

Nov. 1, 1960 J. H. HORMAN PUSH BUTTON swncx-x 2 Sheets-Sheet 1 Filed March 5. 1958 mum .m 0 q m um m r k I/IIIIIIIIIIII/ INVENTOR. JOHN H. HORMAN BY I ATTORNEY FIG il. J

Nov- 1, 196 r J. H. HORMAN 2,958,752

PUSH BUTTON swn'ca Filed March 5. 1958 2 Sheets-Sheet 2 F I G ll 97 95 we 98 INVENTOR. f\ z(\ JOHN H. HORMAN 1 84 A BY -e4a/1/La AT TORNE Y United States Patent 6 PUSH BUTTON SWITCH John H. Horman, Tuckahoe, N.Y., assignor to Allied Control Company, Inc., New York, N.Y., a corporation of New York Filed Mar. 5, 1958, Ser. No. 719,365

3 Claims. (Cl. 200-159) This invention relates to electrical switches. More particularly, it relates to electrical switches of the push button type, that is switches which operate, making or breaking contact, only during the interval of time that a button operatively associated with the switch contacts is depressed.

A primary object of the invention is to provide a basic push button switch construction adapted to convenient modification to meet different service requirements such as normally open or normally closed, single or multiple throw and single or multiple pole.

Additional objects of the invention are to provide an inexpensive yet dependable push button switch and one which can be made small in size.

In the switch of the invention, the push button controls the position of one or more leaf spring contacts which, when moved by the operation of the push -button, either make or break one or more connections between the leaf spring contacts and fixed contacts. The switch construction provided to accomplish this mode of operation and the manner in which the aforementioned objects are attained will be apparent to persons skilled in the art from the accompanying drawings of switches, according to the invention, and the following description of these switches.

iln the drawings, wherein like reference numerals denote corresponding parts throughout the several views:

Fig. 1 is a top view of a single throw, three-pole switch according to the invention;

Fig. 2 is a cross-sectional elevation view of the switch shown in Fig. 1 and taken along line 2-2 of Fig. 1;

Fig. 3 is a cross-sectional elevation view of the switch shown in Fig. 1 and taken along line 3-3 of Fig. 2;

Fig. 4 is a bottom plan view of the switch shown in Figs. 1, 2 and 3;

Fig. 5 is a cross-sectional view taken along line 55 of Fig. 2;

Fig. 6 is a perspective view of the push button employed in the switch of Figs. 1 to 5;

Fig. 7 is a cross-sectional elevation view corresponding to Fig. 2 and illustrates a multi-pole, normally closed switch according to the invention and generally similar to the switch shown in Figs. 1 to 5;

Fig. 8 corresponds to Fig. 7 and is a cross-sectional elevation view of a single-pole, double throw switch according to the invention;

Fig. 9 is a view the same as Fig. 8 but showing the push button depressed;

Fig. 10 is a cross-sectional view taken along line -10-1tt in Fig. 9; and

Fig. 11 is a plan view of a part of a multi-pole double throw switch according to the invention.

Referring to Figures 1-5, there is shown a switch comprising a base member 12, a hollow housing 13 secured to base member 12 by tongues 13 projecting downwardly and inwardly from the lower end of the housing, and a push button 14 slidably mounted in a housing threaded boss 16 which carries a positioning nut 17 and a locking ice nut 18 which are provided to position and secure the switch on, for example, a panel (not shown). The base member 12, which is formed of a suitable insulating material such as, a phenol formaldehyde plastic composition, available under the trademark Bakelite, has a plurality, namely three, fixed electrical contacts 19 fixedly secured thereto by solder slugs 21 deposited in recesses 22 formed in the base member 12. Solder slugs 21 have embedded therein the inwardly disposed ends 23 of headed metal pins 24 which extend through perforations 26 in the base member and secure to the base member electrical terminals 27. Thus the fixed contacts 19 are electrically connected with the terminals 27.

Provided for cooperation with each of the fixed contacts 19 is a leaf spring contact 28 having a free contact end 29 and an anchored end 31. The contact end 29 of each leaf spring contact is moveable and is disposed in operative alignment with its fixed contact so that upon downward movement it will engage its fixed contact making electrical connection therewith. The anchored ends 31 of the leaf spring contacts are secured to the base member 12 by solder slugs 32 which are deposited in base member recesses 33 and the solder slugs 32 are electrically and mechanically connected with terminals 34 by pins 36 in the same manner as fixed contact terminals 27 are connected with solder slugs 21.

As is indicated in Fig. 2 leaf spring contacts 28 are normally spaced from fixed contacts 19, i.e., the switch is normally open, and upon depression of the push button 14, the leaf spring contacts are moved downwardly so that their contact ends 29 electrically engage the fixed contacts 19.

The push button 14 is advantageously generally T- shaped and is formed of a suitable electrical insulating material, preferably of an appropriate synthetic resin, such as molded nylon. The push button comprises a body portion 41 formed by a cylindrical member 42 and a flattened member 43 extending above the cylindrical member 42. The push button body portion is slidably mounted in vertical passageway 39 of boss 1d, the passageway 39 extending completely through boss 16 and communicating with the inside 41) of housing 13. The passageway 39 conforms to the push button body portion 41, and includes a cylindrical section '44 for receiving in close fitting relationship push button cylindrical member 42, and a slotted section 46 for receiving, also in close fitting relationship, push button body portion flattened member 43. The engagement of the push button flattened member 43 by passageway slotted section 45 renders the push button non-rotatable in the passageway 39 and the close fitting relationship of the push button body portion 41 and the passageway 39 precludes tilting of the push button in the boss 16.

Integral with the button body portion 11 and disposed horizontally within the housing 13 over and transversely of the leaf spring contacts 28 and intermediate the end portions thereof, is an actuating bar 47. Depression of the push button 14 causes the actuating bar 4-7 to lower the the leaf spring contact ends 29 and cause them to engage the fixed contacts 19. During this movement the actuating bar remains in its normal transverse relation to the leaf spring contacts due to the non-rotatable mounting of the push button body portion 41 in the boss passageway 33 and thus movement of the actuating bar relative to the leaf spring contacts in a predetermined manner is assured. Hence, electrical connection of all fixed and corresponding movable contacts is effected simultane ously; and successive contacting which would occur if the push button were permitted to rotate so as to dispose the actuating bar at an angle to the leaf springs, is prevented.

When the push button is in its normal position, i.e. not

depressed, the leaf spring contacts 28 urge the actuating bar 47 upwardly into abutting engagement with the inner surface 48 of the housing top 4-9 and the actuating bar thus limits the upward movement of the leaf spring contacts. The actuating bar 47 is of sufficient height that it maintains the end portions 29 of the leaf spring contacts spaced relationship with the housing inner surface 48. This feature permitsforming the housing of metal, Which is highly desirable, as it prevents shortcircuiting from the leaf spring contacts 128 with the housing 13.

The leaf spring contacts 28 are formed of thin strips of resilient metal and in order to prevent injury thereto, the base member 12 is formed with a rib 50 disposed directly beneath the actuating bar 47 so as to limit the travel of the actuating bar.

In Fig. 7, there is shown a switch similar to the switch shown in Figs. 1 to except that it is normally closed. Referring to Fig. 7, the switch comprises a base member 51 having fixedly secured thereto, and electrically connected respectively with

terminals

59 and 60, fixed con- .tacts 5S and leaf spring contacts 57. A housing 52 is disposed over the base member 51 and has mounted atop thereof a boss 53 having a vertically extending passageway 56 in which there is slidably mounted a push button 54-. The leaf spring contacts 57 normally urge the contact ends 61 thereof into electrical engagement with fixed contacts 58 and also hold push button 54 in a raised position. Upon depressing the push button 54, the leaf spring contacts are flexed downwardly thus breaking the connection between the contact ends 61 thereof and the fixed contacts 58. V

InFigs. 8, 9 and there is shown a single pole, double throw switch according to the invention. The switch comprises a base member 71 having a normally closed fixed contact 79 secured thereto and electrically connected with a terminal 76 by a solder slug 83, a leaf spring contact 78 secured thereto and electrically connected to a terminal 75 by a solder slug 85, and a normally open fixed contact 81 secured thereto and electrically connected with a terminal 86 by a solder slug 84. Fixed contact 81 is disposed intermediate the normally closed fixed contact 79 and anchored end portion 89 of leaf spring contact 78 and beneath the movable leaf spring contact. Arranged over the base member 71, is a hollow housing 72 having a boss 73 mounted atop thereof. A passageway 88 extends vertically through boss 73 and has slidably mounted therein a push button 74. An actuating bar 82 is fixedly secured to the inwardly disposed end of the push button 74 and rests on movable leaf spring contact '78 so that movement of the push button will actuate the switch. The actuating bar 82 is disposed in alignment with normally open fixed contact 81, and the working end 91 of the actuating bar tapers to a rounded edge 92 so that working pressure is brought to bear on the movable leaf spring contact 78 directly over the normally open contact 81 when the push button is depressed. Thus a good electrical connection between the movable leaf spring contact 78 and the normally open fixed contact 81 is assured.

The normal position of the switch contacts of the single pole, double throw switch of Figs. 8, 9 and 10 are shown in Fig. 8, the leaf spring contact being in electrical engagement with the normally closed fixed contact 79 and the normally open fixed contact 81 being in spaced relation with the leaf spring contact 78. Upon depressing the push button, as is shown in Fig. 9, the normally closed fixed contact 79 becomes disengaged, and the normally open fixed contact 81 is engaged, by the leaf spring contact 78.

Many modifications of the switch constructions shovm in the drawings can be made by adapting my basic construction to particular service requirements. Thus, for example, the multiple pole, single throw switch shown in Fig. 7 may readily be modified to include a set of normally open fixed contacts so that it would be a nulltiple pole, multiple throw switch and similar in respect to throws to the switch of Figs. 8, 9 and 10.

A multiple pole, multiple throw switch is depicted in Fig. 11. The switch of this modification comprises a base member 94 having a plurality of leaf spring contacts 95 secured thereto by solder slugs 96 which engage the fixed ends 97 of the leaf spring contacts. The leaf spring contacts extend over and above the base member 94 in parallel, side by side relation and terminate under a first set 98 of fixed contacts including fixed

contacts

101, 102 and 1% The fixed

contacts

101, 102 and 103 are secured to the base member 94 by

solder slugs

104, 105 and 106, respectively. A second set 108 of fixed contacts, including contacts 1W9, 110 and 111, is'disposed intermediate the ends of and under the leaf spring contacts 95. The first set 98 of fixed contacts is normally closed and the second set 108 is normally open. A push button actuating bar (not shown) controls the position of the leaf spring contacts in a manner similar to that described heretofore with reference to the other switches depicted in the drawings.

From the foregoing, it is believed that the objects, construction, operation, and advantages of my present invention will be readily comprehended by persons skilled in the art, without further description. Although theinvention has been herein shown and described in several simple and practicable forms, it is recognized that certain parts or elements thereof are representative of other parts or elements which may be used in substantially the same manner to accomplish substantially the same results. Therefore, it is to be understood that the invention is not to be limited to the exact details described herein, but is to be accorded the full scope and protection of the following claims.

I claim:

1. An electrical switch comprising a base member, a plurality of fixed electrical contacts fixedly mounted on the base member, a plurality of leaf spring contacts extending over the base member in spaced parallel relationship, each leaf spring contact including a stationary end portion anchored to the base member and a free end portion disposed in operative alignment with a corresponding fixed contact, said free end portions being normally spaced from the fixed contacts, a housing disposed over the base member, a boss mounted atop the housing and having a passageway extending therethrough and communicating with the interior of the housing, a one-piece generally T-shaped push button including a body portion having a surface so configured as to form a non-rotatable connection with the passageway for sliding movement therein and an actuating bar at the inner end of the body portion, said actuating bar being disposed within the housing over and transverse of the leaf spring contacts intermediate the end portions thereof whereby simultaneous electrical connection of the leaf spring contacts and fixed contacts can be made by depressing the push button, the non-rotatable connection of the push button body portion with the boss passageway maintaining the actuating bar in transverse relation with the leaf spring contacts and preventing rotation of the actuating bar and consequent successive contacting of the leaf spring contacts by the actuating bar, said leaf spring contacts normally urging the push button actuating bar upwardly into abutting engagement with the housing whereby the actuating bar limits upward movement of the leaf spring contacts, said actuating bar normally maintaining the leaf spring contacts with the free end portions thereof in spaced relationship with the housing. g

2. An electrical switch, comprising a base member, a plurality of fixed electrical contacts fixedly mounted on the base member, a plurality of leaf spring contacts extending over the base member in spaced parallel relationship, each leaf spring contact including a stationary end portion anchored to the base member and a free end portion disposed in operative alignment with a corresponding fixed contact, a housing disposed over the base member, a boss mounted atop the housing and having a passageway extending therethrough and communicating with the interior of the housing, a one-piece generally T- shaped push button including a body portion having a surface so configured as to form a non-rotatable connection With the passageway for sliding movements therein and an actuating bar for moving the leaf spring contacts at the inner end of the body portion, said actuating bar being disposed Within the housing over and transversely of the leaf spring contacts intermediate the end portions thereof whereby the positions of the free end portions of the leaf spring contacts relative to the fixed contacts may be changed simultaneously by depressing the push button, the non-rotatable connection of the push button body portion With the passageway insuring movement of the actuating bar relative to the leaf springs in a predetermined manner.

3. An electrical switch comprising a base member, first and second sets of fixed electrical contacts fixedly mounted on the base member, a plurality of leaf spring contacts extending over the base member in spaced parallel relationship, each leaf spring contact including a stationary end portion anchored to the base member and a free end portion in operative alignment with a corresponding fixed contact of the first set of fixed contacts, each fixed contact of the second set of fixed contacts being positioned beneath a corresponding leaf spring contact intermediate end portions thereof, a housing disposed over the base member, a boss mounted atop the housing and having a passageway therethrough and communicating with the interior of the housing, a one-piece generally T-shaped push button including a body portion having a surface so configured as to form a non-rotatable connection with the passageway for sliding movement therein and an actuating bar at the inner end of the body portion, said actuating bar being normal to the body portion and being disposed within the housing over and transversely of the leaf spring contacts intermediate the end portions thereof whereby the positions of the free end portions of the leaf spring contacts relative to the fixed contacts may be changed simultaneously by depressing the push button, the housing limiting upward sliding movement of the push button, the second set of fixed electrical contacts limiting downward sliding movement of the push button.

References Cited in the file of this patent UNITED STATES PATENTS 664,667 Nathans Dec. 25, 1900 674,398 Bower May 21, 1901 1,696,151 Staedeli Dec. 18, 1928 2,722,574 Simmons Nov. 1, 1955