US2957072A

US2957072A - Illuminated switch

Info

Publication number: US2957072A
Application number: US847503A
Authority: US
Inventors: Lester A Rigel
Original assignee: ELDEMA CORP
Current assignee: ELDEMA Corp
Priority date: 1959-10-20
Filing date: 1959-10-20
Publication date: 1960-10-18
Anticipated expiration: 1977-10-18

Description

Oct. 18, 1960 I. A. RIGEL ILLUMINATED SWITCH Filed Oct. 20. 1959 INVENTOR.

LESTER A" RIGEL www Hl AGENT 2,957,072 Patented Oct. 18, 1960 :ice

ILLUIVIINATED SWITCH Lester A. Rigel, El Monte, Calif., assignor to Eldema gorporation, El Monte, Calif., a corporation of Caliorma Filed Get. 20, 1959, Ser. No. 847,503

3 Claims. (Cl. 240-2) This invention relates to illuminated switches, and more particularly to illuminated switches of the miniature pushbutton type adapted for panel mounting.

In the miniaturization of electronic assemblies, particularly with miniature illuminated switches of the general type concerned, diiculties of various kinds are encountered especially in providing for easy replacement of burned-out units, :for the compact disposition of circuit components, and for reliability of the switching elements.

An object of the present invention is to provide an illuminated push-button type switch in which a positive switching action capable of almost indelinite switching without breakdown is provided, together with a convenient disposition of necessary associated circuit elements, and all in a physical form permitting easy replacement of the working part of the unit within its holder.

Other objects of the invention will appear as the description thereof proceeds.

In the drawings, Figure 1 is a longitudinal sectional view of my improved illuminated switch.

Figure 2 is a transverse cross section taken at the level indicated in Figure l.

Figures 3 and 4 show various methods of connecting circuit elements within Ithe switch.

Turning now to Figure 1, this shows a case which is adapted to be mounted in a panel 11 by two

lock nuts

12 and 13. The case terminates in its lower end in a base 14 which is conveniently made of an insulating material such as melamine plastic. The case 10 is most conveniently made of metal, such as aluminum, although brass may be used. The case 10 is of generally cylindrical construction, and bears a slot or keyway 15 running longitudin-ally in its inner wall.

The case serves to retain a replaceable lamp-switch assembly which is generally contained within a principal housing 16, which is terminated at its lower end by a secondary base 17, likewise made of suitable insulating material such as a plastic. As is evident from the drawing, the principal housing 16 is likewise of generally cylindrical construction, and in turn receives at its upper end a cylindrical lamp housing 18. Lamp housing 18 isterminated at its upper end by a translucent cap 19; it contains a lamp bulb 20 with associated leads 21 and 22; and it is terminated at its lower end by a disc 23 which is forcetted into a suitable recessed portion of the end of the lamp housing. The lamp housing 18 is free to slide longitudinally within the principle housing 16, except that its motion outward is limited by la detent means to be described, and its motion inwards is against a compression spring action and terminated by the closing of a switch device, likewise to be described. The translucent cap 19 serves as a convienient means of applying force to the lamp housing so as to push it longitudinally inwards, and may conveniently be made of a suitable plastic material such as polystyrene.

Approximately in the middle of the principal housing 16 there is secured a septum 24 which again is of insulating material. Mounted in the septum 24 are a pair of

tubulations

25 and 26, into which are slidably tted a pair of

rods

27 and 28, which are mounted in the disc 23. Leads 21 and 22 are electrically connected to

rods

27 and 28 respectively. A pair of

helical compression springs

29 and 30 are carried by

rods

27 and 28 and serve the double purpose of urging .the lamp in its housing outwardly and of augmenting the electrical connection between each rod and its associated tubulation, for example rod 27 and tubulation 25. A common difficulty in push switches of the general type under consideration is the uncertainty of electrical connection between fixed and moving parts, but in my present construction I overcome this by the conjoint use of a sliding contact and a direct contact through the spring, as has just been described.

Septum 2.4 also carries a pair of switch electrodes 3:1 and 32, which are terminated by a hemispherical cap on the side facing the lamp and by a simple rod on the side facing the secondary base 17. The disc 23 carries a metal shorting bar 33 which is normally out of contact with

electrodes

31 and 32 because the disc 23 is kept pushed away by the springs. However, when pressure is applied to the cap 19 and the lamp assembly pushed into the principal housing 16, then the metal shorting bar 33 eventually makes contact with the

switch electrode caps

31 and 32, closing any circuit that may be connected through these electrodes. Passing axially through disc 23, through the center of the shorting bar 33, and through the center of the septum 24 is a detent means in the form of a double capped rod 34, which has merely a sliding t through septum 24. This serves to retain the lamp housing 18 within the principal housing 16, but yet permits motion inthe sense of closing the switch.

Secondary base 17 carries a plurality of prong electrodes 35, which iit in tubular electrodes 36 which are mounted in base 14. Base 14 with its electrodes thus forms a terminal block. In general, I will provide at least ve such electrodes, in order to be able toconnect Iup the various circuit elements contained in housing 16. While secondary base 17 is generally round in shape, it carries a lug 37 which engages the keyway 15 in the case 10. This .y makes it possible to remove the entire assembly inside of case 10 and replace it with a new one. Lug 37 and keyway 15 permit accurate engagement of

electrodes

35 and 36.

As will be apparent from Figure 1, I provide a suitable space within principal housing 16 between septum 24 and the secondary base 17. In this space I may put circuit elements as desired. In Figure l there are shown two

resistors

38 and 39. One possible way of wiring up the switch-lamp assembly using the two resistors as shown in Figure 1 is depicted in Figure 3, where the switchV 40 is independent of the lamp 20 and

resistors

38 and 39, although contained within 'the same encasement. In certain applications of my illuminated switch, it is desirable to make use of a transistor 41, wired so as to cooperate With Vthe switch and @the lamp all as shown in Figure 4.

The Vparticular circuits usable with my device are known:

to those skilled in the art, and need not be described in greater detail herein.

It will be seen that the invention accomplishes its objects, and the superiority of the inventive construction has been -amply demonstrated by severe testing programs, which have shown that the combination of elements not only coact in the manner shown but are capable of doing so over extended periods of use. I attribute these results in part to lthe positive switching action as provided by the shorting bar and the switch electrodes, the positive electrical connection through the moving portion of the switch, the placement of the circuit elements in a relatively cool part of the case instead of near the lamp bulb as commonly done, and to like factors.

It will be apparent that while my invention has been described in terms of a particular embodiment, numerous variations of detail are permissible within `the broad scope of lthe invention as defined by the appended claims.

Having described my invention l claim:

l. In an illuminated switch, in combination, a principal housing of generally tubular form; a lamp housing of tubular form and telescopically tted into one end of said principal housing; a lamp having a pair of electrode leads and contained within said lamp housing; hase means secured by said lamp housing -at the end thereof within said principal housing; a septum mounted in said principal housing and spaced from said base means; a pair of tubulations mounted within said septum and parallel to the axis of said principal housing and said lamp housing; a pair of rod means secured to said base means electrically connected to said lamp electrode leads and slidably fitted within said tubulations; a pair of helical springs carried by said rod means intermediate of said base and of said tubulations and physically contacting both said rod means and said tubulations and es-tablishing elec-trical contact between each rod and its corresponding tubulation; detent means restraining said lamp housing from being pushed out of said principal housing by said springs; a metal bar attached to the bottom of said base means and facing said septum; a pair of switch electrodes mounted in said septum out of contact of said tubulations and adapted to be contacted by said metal bar; =a principal housing base carrying a multiplicity of electrodes communicating from the interior of said principal housing to the exterior of said principal housing base; and electrical conduction means establishing electrical connection between said principal housing base electrodes and said tubulations and said switch electrodes.

2. In an illuminated switch, in combination, a principal housing of Vgenerally tubular form; a lamp housing of tubular form and telescopically tted into one end of said principal housing; a lamp having a pair of electrode leads and contained within said lamp housing; an at least -translucent cap means on the end of said lamp housing without said principal housing; base means having electrodes thereon and secured by said lamp housing at the end thereof within said principal housing; a septum mounted in said principal housing and spaced from said base means; a pair of tubulations mounted within said septum and parallel to the aXis of said principal housing and said lamp housing; a pair of rod means secured to said base means and slidably iitted Within said tubulations, said lamp electrode means being electrically connected to said pair of rod means; a pair of helical springs carried by said rod means intermediate of said base and of said tubulations and physically contacting both said rod means and said tubulations and establishing electrical contact between each rod and its corresponding tubulation; a detent means comprising a double capped rod passing through said base means and through said septum; a metal bar attached to the bottom of said base means and facing said septum; a pair of switch electrodes mounted in said septum out of contact of said tubulations and adapted to be contacted by said metal bar; a principal housing base carrying a multiplicity of electrodes communicating from the interior of said principal housing to the exterior of said principal housing base, said principal housing electrodes being electrically connected lto said pair of tubulations and said pair of switch electrodes; and circuit element means connected by means of wire leads in the lamp circuit disposed within the space deiined by said septum and Said principal housing base.

3. in an illuminated switch, in combination, a casing of generally tubular form open at one end and closed at the other by a terminal block having electrodes thereon; a principal housing of generally ytubular `form -telescopic-ally fitted into said casing; a lam-p housing of tubular form and telescopically fitted into one end of said principal housing; a lamp having a pair of electrode leads and contained within said lamp housing; an at least translucent cap means on the end of said lamp housing without said principal housing; base means secured by said lamp housing at the end thereof within said principal housing; a septum mounted in said principal housing and spaced from said base means; ya pair of tubulations mounted within said septum and parallel to the axis of said principal housing and said lamp housing; `a pair or rod means secured to said base means and sl-idably tit-ted Within said tubulations, said lamp electrode leads being electrically connected to said pair of rod means; a pair of helical springs carried by said rod means intermediate of said base and of said tubulations and physically contacting both said rod means and said tubulations and establishing electrical contact between each rod and its corresponding tubulation; a detent means comprising a double capped rod passing through said base means and through said septum; a metal bar attached to the bottom of said base means and facing said septum; a pair of switch electrodes mounted in said septum out of contact of said tubulations and adapted to be contacted by said metal bar; a principal housing base carrying a multiplicity of electrodes communicating from the interior of said principal housing to the eX- terior of said principal housing base, said principal housing electrodes being electrically connected to said pair of tubulations and said pair of switch electrodes, and said principal housing base electrodes being electrically connected to said terminal block electrodes when said principal housing is in place in said casing; and circuit element means comprising resistors and transistors connected by means of wire leads in `the lamp ycircuit disposed within the space delined by said septum and said principal housing base.

References Cited in the lile of this patent UNITED STATES PATENTS 2,430,189 Schellman Nov. 4, 1947 2,710,955 Hallerberg e-t al. June 14, 1955 2,730,705 Hallerberg et al. Jan. l0, 1956 2,847,559 Harrington et al Aug. 12, 1958