US1520025A - Switch for portable electric lamps - Google Patents

Description

Dec, 23, 1924.

H. H. HIPWELL swITcH FOR PORTABLE ELECTRIC LAMPS Filed Aug. 13, 1923 Patented Dec. 23, 1924.

UNITED STATES HARRY H. I-IIPWELL, OF PITTSBURGH, PENNSYLVANIA.

SWITCH FOR PORTABLE ELECTRIC LAMPS.

Application filed August 13, 1923.

To all whom t may concern.'

Be it known that I, HARRY H. I-lirwnm., a citizen of the United States, and resident of Pittsburgh, in the county of Allegheny and State of Pennsylvania, have invented a new and useful Improvement in Switches for Portable Electric Lamps; and I do hereby declare the following to be a full, clear, and exact description thereof.

My invention relates to portable electric lamps of the type known as flashlights, and its object is to provide an improved switch for lamps of this character which shall include means for preventing the switch from being accidentally closed.

Ordinary portable flashlights are provided with switches attached to the outside of the casing which encloses the battery, and these switches are usually arranged to close the electric circuit either by depressing the movable contact member when a temporary flash of light is desired, or by sliding the movable member into such position that the circuit is kept closed after the movable contact member is released. l/Vhen a flashlight of this kind is carried in the pocket, in a traveling bag or in an automobile pocket or the like, the movable switch member' is often accidentally slid into the closed position, thereby wasting the energy of the battery.

According to my 1aresent' invention, I provide a switch for :flashlights which, like ordinary switches, may be closed either to produce a temporary flash or a more continuous light, and in which it is impossible to slide the movable contact member into circuit-closing position accidentally. The movable contact member is normally held in such a position that, before closing the electric circuit, it is necessary to draw back the movable contact member and then move the movable contact member toward the fixed contact member. By this means I prevent useless illumination, and the movable switch member may be slid back and forth either intentionally or accidentally without closing the circuit.

In the accompanying drawing, Fig. 1 is a full-sized side elevational view of a cylindrical flashlight provided with a switch constructed in accordance with mv invention; Fig. 2 is an enlarged longitudinal sectional view through the switch and the adjacent portion of the battery casing, the section being taken on the line 2 2, Fig. 1: Figs. 3 and 4L are longitudinal sectional views simi- Serial No. 657,135.

lar to F ig. 2, showing other positions of the movable contact member, and F ig. 5 is an enlarged perspective view of the movable contact member detached from the other parts of the switch.

In the drawing, the numeral 2 indicates the circular casing of a flashlight having an enlarged head 3 which encloses the usual lamp bulb, not shown, and which is provided with a screw cap L1 and with a lens 5. The end of the casing 2 opposite to the head 3 is closed by means of the usual screw cap G.

Secured to the outer surface 0f the casing 2 by means of eyelets 7, is a switch casing 8 having a slot 9 formed lengthwise in its upper surface, through which extends the shank 10 of a switch button 11. The button 11 is secured to a movable contact member 12 which, as best shown in Fig. 5, consists of a bent piece of spring metal having a straight upper portion 13, and a` lower portion la having its forward end bent up slightly as shown at 15. The front end of the upper portion 13 is provided with two slits which form a tongue 16 that is bent down, leaving two forwardly projecting ears 17.

lllithin the switch casing 8 is a fixed contact member 18 consisting of an eyelet which extends through the wall of the casing 2 and secures within this casing the usual conducting strip 19 that leads to one terminal of the lamp bulb. The other conducting strip 2() is connected as usual to the casing 8 by means of one of the eyelets 7.

The switch casing S is provided with a transverse opening 21 which is made by forming a slit in the flat upper surface of the casing 8 and bendingdown the metal adjacent to this slit to form a ledge 22 which, when the movable switch member 12 is slid forward without being first depressed, engages the ears 17 and prevents the movable contact member from coming into contact with the fixed Contact member 18 either by further sliding movement or by depressing movement.

Fig. 2 shows the parts of the switch in their inactive position, with the shank 10 of the button 11 at the rear of the slot 9. The down-turned end portion 16 of the movable contact member 12 is directly above the contact eyelet 1S, and the circuit may be completed through the lamp by depressing the button 11 to the position shown in dotted lines, Fig. 2, where the members 1G and 1S llll are incontact. When the button 11 is released, the movable contact rises away from the fixed contact member 18. This is the normal operation for producing temporary fiashes of light after the movable contact has been released by drawing the button 11 back to the rear of the slot 9.

Fig. shows the effect produced when the button 11 is moved forward in the slot 9 without first depressing the button. As shown in this figure, the ears 17 of the movable Contact member are received by the transverse ledge 22 of the casing, and the parts are so proportioned that when this f takes place the lower member 14 of the movable contact member cannot come into engagement with the eyelet 1S. The button 11 can now be neither depressed or moved forward but can only be moved back to the inactive position shown in Fig. 2. The switch is preferably moved to this safety position before the flashlight is placed in a pocket, traveling bag or the like.

lVhen it is desired to bring the lower portion 14 of the movable contact member into engagement with the eyelet 1S to produce a continuous beam of light, the button 11 is first drawn back to release the member 12 from the ledge 22 and is then depressed to bring the ears 17 below the level of the ledge 22. The button 11 may then be slid to the front end of the slot 9, as shown in Fig. 4. This brings the switch members 14 and 18 into engagement and completes the circuit through the lamp. The circuit remains closed until the button 11 is moved back in the slot 9 to separate the contact members. As the button 11 approaches the rear of the slot 9, the ears 17 are released by the ledge 22 and the upper part 13 of the contact member 12 snaps back into the position shown in Fig. 2.

It will be noted that the switch herein shown is provided with the safety feature described above without adding any parts to the switch and by employing only a single fixed' eyelet 18. It will also be seen that the addition of the safety feature does not detract from the convenience of using the switch, and that the engagement of the switch members for producing continuous light is improved by placing the movable Contact member under tension when it is brought to the position shown in Fig. 4.

I have shown and described herein the details of construction which I now prefer to employ, but it will be understood that varions changes may be made without departing from my invention as set forth in the appended claims.

I claim as my invention:

1. A switch for portable electric lamps comprising a casing, a fixed contact member within said casing, a movable contact member having an operating element extending through a slot in said casing, said movable contact member comprising a strip of spring metal having one end portion adapted to slide into engagement with said fixed contact member and having means at its opposite end for engaging said fixed contact member by direct inward movement, and means for engaging said movable contact member when said movable contact member is advanced toward said fixed contact member without preliminary inward movement, and for thereby locking said movable contact member against further advancing or inward movements and preventing engagement between said contact members.

2. A switch for portable electric lamps comprising a casing having a slot formed therein, a movable contact member Within said casing and comprising an operating member extending through said slot and a strip of spring metal bent to form inner and outer arms, a fixed contact member within said casing, the inner arm of said movable contact member being adapted to engage said fixed contactmember by sliding movement, and said outer arm being adapted to engage said fixed contact member by direct inward movement, and an obstruction carried by said casing and adapted to engage the outer arm of said movable Contact member and thereby prevent engagement of either of said arms with said fixed contact member when said movable contact member is slid toward said fixed contact member without first depressing said operating member.

8. A switch for portable electric lamps comprising a casing having an elongated slot and also having a second slot extending transversely to said first-named slot, a ledge or obstruction formed by depressing a portion of the casing adjacent to said secondnamed slot, a movable contact member slidable within said casing and having an operating element extending through said firstnamed slot, and a fixed contact member within said casing, said movable contact member having a portion ada ted to engage said ledge when said movab e contact member is moved toward said fixed contact member without first depressing said operating element.

4. A switch for portable electric lamps comprising a casing having a slot formed lengthwise therein and also having a tra-nsverse slot spaced from one end of said lengthwise slot, the said casing adjacent to said transverse slot being bent down on the side opposite to said lengthwise slot to form an obstruction or ledge, a fixed contact member within said casing, a movable contact member slidable within said casing and having an operating element extending through said lengthwise slot, said movable contact member being composed of a bent strip of spring metal having an inner arm adapted to move slidably into engagement'with said fixed Contact member, and having an outer `arm formed With an nturned end portion for engaging said fixed Contact member by direct inward movement, the outer arm of Said movable Contact member also having forwardly-extending ears adapted to engage said ledge or obstruction when said movable Contact member is moved toward said IiXed Contact member without iirst depressing said l0 operating element to bring the outer arm of Said movable Contact member beneath said ledge or obstruction.

In testimony whereof I, the said HARRY H. HIPWELL, have hereunto set my hand.

HARRY H. HIPWELL.

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