US2852634A - Flashlight construction - Google Patents

Description

Sept. 16, 1958 E. J. GARLAND 2,852,634

FLASHLIGHT CONSTRUCTION Filed July 5, 1955 2 INVENTOR l dwardcffiarlamd States FLASHLKGHT CGNSTRUQTION Application July 5, 1955,.Serial No. l9,8$5

3 Claims. (Cl. 200-60) This invention relates to a novel electrical switching mechanism and particularly to a novel electrical switching mechanism adapted for use with a tubular flashlight casing.

Flashlights now commonly in use are .customarily provided with a push-button type of switch. In the most common type of switch, it is usually necessary to depress a small button in order to complete the electrical circuit. A slide may then be advanced toward the front and of the flashlight to lock the button in a depressedcondition and keep the circuit of the flashlight in a closed position, for the provision of a beam of light continuously; A major disadvantage of switches of this type resides in the difficulty of locating and maneuvering the switch in darkness and in emergency situations.

A principal object of the present invention is to provide a novel type of flashlightswitch mechanism which will be very easy to locate and operate in the darkness and under'other disadvantageous conditions.

Another object of the invention is to provide a switch for a flashlight which is a major feature inthe silhouette or contour of the flashlight, readily discernible to the! Vision as well as to the touch.

A further object of the invention is to provide a ring switch for a tubular flashlight casing which is operated by longitudinal sliding motion of the ring, and which is so constructed as to lock in either the on? or the normally disposed out of electrical contact with an electrical connector member which is permanently electrically connected with the reflector bowl and hence with the flashlight lamp filament. The inner surface of the ring is desirably a simple cam, with the upper surface of the metal contact spring mounted therein functioning as a cam follower. Forward longitudinal sliding movement of the ring depresses the metal contact spring into electrical connection with the electrical connector member, completing the flashlight circuit and energizing the lamp filament. Rearward sliding movement of the ring will allow the metal contact spring to assume its normal outwardly biased disposition, out of contact with the electrical connecting member, thus breaking the circuit and tie-energizing the lamp filament. The rearward movement of the ring is desirably restricted by a stop which is an integral part of the contact spring and which moves simultaneously therewith.

These and other details of the construction and operation of the ring switch of this invention may be best understood by referring to the accompanying drawings, in which:

Fig. 1 is a side elevational view in partial section of sulating fiber strip thereto.

- 52,634 Patented Sept. 16, 1958 a flashlight casing including a ring switch according to the present invention;

Fig. 2 is a greatly enlarged partial sectional view of the switch mechanism illustrated in Fig. 1, showing the switch with the flashlight in the on position; and

Fig. 3 is a fragmentary top plan view of the switch mechanism, cut away to illustrate the outwardly biased contact spring.

Referring now in detail to the drawings, a flashlight casing l is provided, as is conventional, with a bottom contact spring 2, a pair of dry cells 3, a contact'base 4, and a reflector bowl assembly 5. Positioned within the reflector bowl assembly 5 is a flashlight bulb having one filament in electrical contact with the top terminal of the front dry cell in the flashlight casing, and having the other filament in electrical connection with a metallic conductive surface such as a coating for example on the undersurface of the reflector bowl 5. Electrical connection between the copper coating on the undersurface of the reflector bowl 5 and the switching mechanism of the invention is provided by an electrical contact member 6, which is permanently positioned in electrical contact with the reflector bowl undersurface, and which extends back into the casing and is secured to the casing by a pair of rivets 7A'and 7B. The connector member 6 is insulated from the flashlight casing by an interposed fiber strip 8 which is secured to the electrical connector member 6 by a pair of rivets 9'. The same fiber strip is desirably of sufficient length to be interposed between the connector member 6 and the flashlight casing 1 adjacent the rivet 7A disposed nearest the front end of the flashlight. The presence of the fiber strip, together with a small aperture or slot in the connector member 6, electrically insulates the rivet 7A and the electrical connector member 6. Electrical contact between the connector member 6 and the dry cells in the flashlight is prevented by the provision of a second fiber strip 10 on the undersurface of the connector member 6. The second fiber strip 10 may be secured to the connector member 6 by the same rivets 9 securing the upper in- The lower or second insulating strip 10 desirably extends well into thecasing beyond the connector member 6, and is secured at an end thereof to the flashlight casing by the rear rivet 7B.

In order to complete the flashlight circuitand energize the filament of the lamp bulb, with. the circuit just described, it is merely necessary to provide an electrical connection between the flashlight casing and the electrical connector member 6. This is accomplished by a cam and follower device, in which a metal contact spring 16 functions as the follower, and is urged into contact with the exposed end 17 of the electrical connector member 6, hereinafter referred to as the contact strip 17, by the forward sliding movement of a cam ring 18.

Referring temporarily to the enlarged section shown in Fig. 2, it can readily be seen that the lowermost insulating strip it) extends into the casing beyond the switch elements, and is secured to the casing by the rear rivet 7B. The upper insulating fiber strip 8 extends into the casing past the front rivet 7A and terminates immediately beyond the rivet, leaving exposed the contact strip 17. A metallic contact spring 16 is secured to the flashlight casing by the rear rivet 7B, with a free end of the contact spring being disposed adjacent the contact strip 17 so that, with the flashlight in the on position illustrated in Fig. 2, the free end of the contact spring is in physical and electrical contact with the contact strip 17 Control over the movement of the metal contact spring 16 is obtained through reciprocal sliding movement of the cam ring 18 which is mounted around the casing over the metal contact spring 16. A pair of lateral flanges 19 and 2t engage the underlyin surface of the flashlight casing in a moderately loose, sliding engagement. The

cam action of the ring is provided by the contour of the inner surface of the central portion of the ring 28. As is clearly illustrated in Fig. 2, when the cam ring is in its extreme forward position, the rear lateral flange 2G is in positive engagement with the contact spring 16 and retains the free end of the contact spring in close engagement with the contact strip 17, thereby locking the circuit in a closed position. When it is desired to turn off the flashlight, it is merely necessary to slide the cam ring 18 rearwardly. As the cam ring moves toward the back end of the flashlight, the cammed inner surface 28 of the cam ring 18 allows the metal contact spring 16 to rise out of engagement with the metal contact strip 17, thus breaking the circuit and de-energizing the lamp filament.

Rearward movement of the cam ring is restricted by the abutting engagement of a stop member 29 with the opposed inwardly directed wall 31 of the cam ring 13. The stop member 29 may be constructed very simply as a struck-up portion of the metal contact spring 16. Forward movement of the cam ring is restricted by abutment of the forward lateral flange 19 of the cam ring against a shoulder 22 encircling the tubular body of the flashlight casing adjacent its front end. It may be noted that the cam ring 18 is free to rotate about the tubular casing ll of the flashlight, but this does not interfere in any way with the operation of the switch. If desired, rotary movement may be prevented by the provision of a simple stop mechanism.

In the preferred embodiment of the invention described above, there have been mentioned many conventional structural components of the flashlight as distinguished from the novel switch combination. It should be understood that certain modifications in this preferred embodiment of the invention may be made by the substitution of equivalent components for those which have been described. For example, while it is preferred that the flashlight casing and the cam ring be fabricated of metal, the flashlight casing may be manufactured from a synthetic plastic material, as may the cam ring also. In the case where the flashlight casing is made from a non-conductive synthetic plastic material it would be necessary to provide supplemental electrical connection between the metallic contact spring 16 and the container electrode of the rear dry cell in the flashlight. Similarly, the switching elements, such as the electrical connector member 6 and its associated insulating fiber strips, and the metal contact spring 16, may be duplicated at one or more points within the flashlight casing in circumferentially spaced relation. This would assure a more positive contact and would avoid the danger of exceptionally hard usage on a single switch element. In addition, this type light circuit.

I claim:

1. In an electrical flashlight having a tubular casing adapted to house at least one energizing battery and pro vided with a flared head, a reflector bowl and lamp within said head, the improvement which comprises a circumferentially mounted ring switch on said tubular casing, at least one port in said casing, said ring switch being moveable toward and away from said head by limited reciprocation along the outer surface of said tubular casing and over said port, a conductive strip, insulated from said casing, one end of said strip being in conductive contact with said reflector bowl the other end of said strip being disposed beneath said port, a spring contact member one end of which is affixed to said casing in conductive contact therewith and the other end of which is disposed opposite said port and normally sprung upwardly and away from said strip, said ring switch having a lateral flange on each side of a raised, annular, groove a portion of the interior of which is so shaped and proportioned as to house the upwardly sprung end of said spring contact member without biasing it downwardly when opposite said port, and the rear flange of said ring switch biasing said spring contact member into conductive contact with said contact strip when opposite said port, said ring switch being freely rotatable around the entire circumference of said casing.

2. The improvement of claim 1 in which the upwardly sprung end portion of said spring contact member is bent to provide a cam-following surface and the interior of said raised groove in said ring switch is shaped to provide a coacting cam surface.

3. The improvement of claim 2 in which the upwardly sprung end portion of said spring contact member has a tongue struck upwardly from the remaining portion of said end to provide a stop preventing excessive downward movement of said ring switch.

References Cited in the file of this patent UNITED STATES PATENTS 1,874,788 Moran Aug. 30, 1932 2,174,877 Graubner et a1. Oct. 3, 1939 2,226,353 7 Wood Dec. 24, 1940 2,339,356 Sachs Jan. 18, 1944 2,464,184 Pearce Mar. 8, 1949 2,769,896 Lambert Nov. 6, 1956 FOREIGN PATENTS 375,274 Great Britain of 1932

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