US3778820A

US3778820A - Indicator assembly with interlocking contact

Info

Publication number: US3778820A
Application number: US00251462A
Authority: US
Inventors: Benschoten P Van; J Kilsdonk
Original assignee: Oak Industries Inc
Current assignee: Oak Industries Inc
Priority date: 1972-05-08
Filing date: 1972-05-08
Publication date: 1973-12-11
Anticipated expiration: 1990-12-11

Abstract

An indicator assembly using a flanged lamp and having a housing which includes a pair of lamp contacts. The lamp is electrically connected to the contacts, with one of the contacts biasing the flange of the lamp into an interlocked position with the housing to thus hold the lamp in position, but yet permit easy removal of the lamp from the front of the indicator assembly.

Description

United States Patent [191 Van Benschoten et al.

[ Dec. 11, 1973 INDICATOR ASSEMBLY WITH INTERLOCKING CONTACT [75] Inventors: Peter J. Van Benschoten, Rancho Santa Fe; Jan Albert Kilsdonk, Corona, both of Calif.

[73] Assignee: Oak Industries Inc., Crystal Lake,

[22] Filed: May 8, 1972 I21| Appl. No: 251,462

[52] US. Cl 340/381 R [51] Int. Cl. G08b 5/00 [58] Field of Search 340/381 R [56] References Cited UNITED STATES PATENTS 2,207,507 7/1940 Douglas 340/381 2,705,318 3/1955 Hallerberg 340/381 3,007,599 11/1961 Greasley 340/381 X 3,115,308 12/1963 Stark 340/381 X 3,489,891 1/1970 Altissimo 340/381 X Primary ExaminerHarold I. Pitts Attorney-H0ward T. Markey et a1.

[ ABSTRACT 14 Claims, 8 Drawing Figures INDICATOR ASSEMBLY WITH INTERLOCKING CONTACT SUMMARY OF THE INVENTION This invention relates to an indicator and specifically to an indicator in which the lamp contacts provide the interlock between the lamp and the housing.

Another purpose is an indicator assembly of the type described utilizing fewer parts tothus provide a more reliable and less expensive indicator.

Another purpose is a combination switch and indicator of the type described.

Another purpose is an indicator of the type described which accepts a common flange base lamp.

Another purpose is an indicator assembly of the type described in which the lamp may be replaced from the front, eliminating the necessity of access to the back side of the panel.

Another purpose is a panel indicator and switch combination in which the switch button functions as the lens and may be removed from the front to provide access to the lamp.

Other purposes will appear in the ensuing specification, drawings and claims.

BRIEF DESCRIPTION OF THE DRAWINGS The invention is illustrated diagrammatically in the following drawings wherein:

FIG. 1 is a diagrammatic illustration of an indicator assembly of the type described positioned for insertion into a panel board,

FIG. 2 is a diagrammatic illustration, similar to FIG. 1, showing the method of removal of the indicator lens,

FIG. 3 is a diagrammatic illustration, similar to FIGS. 1 and 2, illustrating the method of removing the lamp from the indicator assembly,

FIG. 4 is a side view of the indicator assembly,

FIG. 5 is a bottom view of the indicator assembly,

FIG. 6 is a top view of the indicator assembly, with the lamp and lens removed,

FIG. 7 is an enlarged section along plane 7-7 of FIG. 6, and

FIG. 8 is an enlarged section along plane 88 of FIG. 6.

DESCRIPTION OF THE PREFERRED EMBODIMENT The present invention will be described as a combination indicator and pushbutton switch. However, it should be understood that the principles disclosed and claimed are applicable to indicators without a switching apparatus therein.

In FIG. 1 a typical control panel is indicated at 10 and an indicator and switch assembly of the type described herein, indicated at 12, has been inserted into an opening in the panel. A second indicator 14 is positioned for insertion into an opening 16 in the panel.

The indicator assembly includes a housing formed of two halves shown at 18 and 20 in FIG. 5. As can be seen, the housing halves l8 and 20 are symmetrical and identical. They may be formed of plastic or any suitable material. Retaining clips or the like 22 and 24 are attached to the outside of the housing for use in holding the indicator within the panel opening. The

retaining clips

22 and 24 have inwardly-extending

flanges

26 and 28, illustrated in FIG. 7, which fit into mating grooves in the exterior surface of the housing halves l8 and 20 to hold the retaining clips in position on the indicator. The upper inwardly-directed

surfaces

30 and 32 of the retaining clips may be notiched or grooved to provide a surface which resists removal of the indicator from the panel.

Turning particularly to FIG. 7, there are a pair of

lamp contacts

34 and 36. Lamp contact 36 extends through an opening 38 in the bottom of one of the housing halves and has a portion 40 which extends within the housing. A lamp receiving portion 42 of the contact 36 is positioned to be in electrical contact with the bottom or base of a conventional flanged lamp 44. The lamp 44 has a flange 46 and is positioned within a cylindrical portion or a lamp receiving portion 48 of the housing. The portion 48 is defined by inwardlyextending areas of the housing halves l8 and 20, indicated at 50.

Lamp contact 34 has a portion 52 which extends into the housing and has a lamp contacting portion 54 which extends upwardly into the lamp receiving portion 48 and is in electrical contact with a side portion of the lamp 44. The lower end of the lamp receiving portion 48 is defined by a shoulder 56. As indicated in FIG. 7, the flange 46 is positioned under the shoulder 56. In practice, the lamp is inserted into the lamp receiving passage 48 and is pressed downwardly until the bottom of the lamp is in contact with the lamp contact portion 42. Lamp contact portion 54 exerts a lateral force upon the lamp 44, moving the flange 46 under the shoulder 56. Contact portion 42 exerts an upwardlydirected force to hold the flange against the shoulder. Thus, the spring effect of the flexible lamp contacts effectively lock the lamp to the housing.

The indicator assembly includes a lens 60 which is in alignment with the lamp 44 and the lamp receiving portion 48. The lens 60 has a pair of inwardly-directed

projections

62 and 64 which extend within the housing and have outwardly-extending

hooks

66 and 68 which fit beneath and interlock with

shoulders

70 and 72 on the interior surface of the housing. Thus, the lens 60 may be snapped into the housing and is held in place by the described interlock. The lens may be easily removed, by giving it an outward pull, to provide access to the lamp.

A pair of switch terminals are indicated at 74 and 76 and are shown particularly in FIG. 8. Each of the

switch terminals

74 and 76 extend within the housing, and in the normally open position of FIG. 8 are spaced from a wiper blade 78. The wiper blade 78 has terminal contacting

portions

80 and 82 which are positioned to be placed in electrical contact with the

terminals

74 and 76 when the switch is operated. A coil spring 84 is seated on the bottom of the housing and normally biases the wiper blade 78 in an outward direction. Note the interrelationship between the

projections

62 and 64, the wiper blade and the spring shown in FIG. 8. When the lens 60, which functions as the switch operator or button, is depressed, the

projections

62 and 64 move inwardly, pressing the

ends

80 and 82 of the wiper blade into contact with the

terminals

74 and 76 to thus complete the circuit between the two terminals.

The switch terminals are electrically isolated from the lamp contacts by a barrier 86 formed of inwardlyextending projections integral with the housing. The wiper blade 78 is normally biased by the coil spring 84 against the bottom of the barrier 86.

In operation normally the lamp will be lit whenever contacts 34 and 36 are electrically connected to a source of voltage. Movement of the lens 60 in an inward direction will connect

terminals

74 and 76 so that the indicator assembly not only performs an indicating function, but also performs a switching function. In some applications the lamp contacts may be connected with the switch terminals so that the lamp will be lit when the switch is operated.

Of particular importance is the fact that the lens may be removed from the front of the indicator housing merely by pulling it outward. When the lens has been pulled outward, the lamp is accessible, thus avoiding any necessity of access to the back of the panel where high voltage may be present. To remove the lamp, as indicated in FIG. 3, the lamp is pushed sideways against the spring tension of the contacts. As the lamp is pushed sideways, flange 46 moves outwardly from under shoulder 56, thus releasing the lamp for removal from the indicator assembly. When the lamp is inserted, it is merely pushed downwardly until the biasing force of

contact portions

54 and 42 holds flange 46 under shoulder 56.

Of importance is the fact that the lamp contacts provide the interlock between the lamp and the housing, thus eliminating a number of parts used in prior indicators. Since the number of metal parts is reduced, the indicator is less expensive and more reliable. In addition, a conventional flange based lamp, readily available throughout the world, is used as the lamp, thus avoiding any necessity of having specially made lamps.

Whereas the preferred form of the invention has been shown and described herein, it should be realized that there may be many modifications, substitutions and alterations thereto.

We claim:

1. in an indicator assembly, a housing having an open end, a lamp receiving portion of said housing in alignment with said open end, a pair of lamp contacts, one of said lamp contacts being positioned in alignment with said lamp receiving portion and said open end and having a portion arranged to contact an end of the lamp, the other of said contacts having a flexible portion positioned to contact a side portion of the lamp, said other contact biasing the lamp laterally into an interlocked position with the housing.

2. The structure of claim 1 further characterized in that both contacts exert a biasing force on the lamp to interlock it with the housing.

3. The structure of claim 1 further characterized in that said housing includes a shoulder forming a part of the lamp receiving portion, the lamp having an outwardly-extending flange, said other contact biasing the lamp flange into an interlocked position with the housing shoulder.

4. The structure of claim 3 further characterized in that said lamp receiving portion includes a generally cylindrical portion, said shoulder being positioned at one end of said cylindrical portion, said other contact portion extending into the cylindrical portion to contact the side portion of the lamp.

5. The structure of claim 4 further characterized in that said other contact biases said flange beneath said shoulder.

6. The structure of claim 5 further characterized in that said one contact biases the lamp upwardly against the shoulder.

7. The structure of claim 1 further characterized in that said housing includes a pair of symmetrical halves.

8. The structure of claim 1 further characterized by and including a lens connected to said housing and positioned outside of the lamp.

9. The structure of claim 8 further characterized by and including a pair of switch terminals extending into said housing, said lens being movable relative to the housing to effect the opening and closing of said switch terminals.

10. The structure of claim 9 further characterized by and including a spring positioned within said housing and normally biasing said lens in an outward direction.

11. The structure of claim 10 further characterized by and including a wiper blade positioned for contact with said terminals and arranged to be moved into contact with the terminals by said lens.

12. The structure of claim 11 further characterized in that said lens includes inwardly-extending projections positioned for contact with said wiper blade to effect movement of the wiper blade into contact with the switch terminals.

13. The structure of claim 12 further characterized in that said lens is removable, with said projections including means for attaching the lens to the housing.

14. The structure of claim 1 further characterized by and including retaining clips positioned on the outside of said housing for use in attaching the indicator into a panel board or the like.