CA1293231C

CA1293231C - Flashlight with a backup system

Info

Publication number: CA1293231C
Application number: CA000560310A
Authority: CA
Inventors: David R. Schaller; El-Sayed Megahed; James Neyer; Tor Pettersen
Original assignee: Rayovac Corp
Current assignee: Spectrum Brands Inc
Priority date: 1987-08-04
Filing date: 1988-03-02
Publication date: 1991-12-17
Anticipated expiration: 2008-12-17
Also published as: KR890005130U; KR910007516Y1; GB2207744B; GB2207744A; US4803605A; GB8802337D0; JPS6443901A

Abstract

ABSTRACT OF THE INVENTION

A hand-held flashlight has a housing for two independent electrical systems: a primary system and a backup system. Each of the systems includes a light source, a power source and a switching device for selectively connecting a power source to a corresponding light source. The backup system uses high performance components to insure that the flashlight is operational for long time periods. The backup system is ctivated only after the the primary system has failed. An indicator announces when the backup system is in operation.

Description

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A FLASHLIGHT WITH A BACKUP SYSTEM

~ ACKGROUND OF THE INVENTION

2 ¦ Field of InventiOn 3 l This invention pertains to a flashlight constructed 4 ¦ with several redundant elements for long-term reliability and S ¦I more particularly to a hand-held flashlight with a backup 6 ll system which may be selectively activated when the primary 7 1 electrical system has failed.
8 1 Descriptlon of the Prior Art i 9 Flashlights, and especially hand-held flashli~hts are ll used in many instances as primary sources of light in locations 11 , which are situated too far for the use of light sources 12 ~I connected to an electric power distribution network, or in 13 , which locations the distribution network has failed.
14 IFrequently these flashlights, and especially the flashlights lS desiynated for emergency use only, are store~d away for long 16 time periods between activations. However the flashlights 17 presently available are subject to failure even if they are not 18 1 used frequently. Conventional flashlights usually have a 19 ,llsingle electrical system comprising one or more batteries which ¦provide the power for the flashlight, a light bulb which 21 ll generates the actual light beam, a switch for the selective 22 1 actuation of the bulb, and interconnecting elements which 23 ; provide the electrical pa~h between these elements. All these 24 lelements are disposed in a common housing and the failure of lany one of these elements results in the malfunction of the 26 flashlight. For example, common batteries have a very limitted 27 shelf life. After a relatively short time period has elapsed, 28 these batteries are discharged even if they are not used.
29 ,Furthermore the common batteries can produce various corrosive !I fumes which can desrade and ultimately cause the failure of the ~Z~;~Z3~

l I housing, the switch or the flashlight interconnecting elements.
2 1 The switch is a mechanical device which is also prone to 3 ,1 failure. Frequent activation of the flashlight causes a 4 I premature failure due to abnormal wear and tear of the contacts l¦ as well as metal fatiyue of its components. If the switch is 6 1¦ used infrequently, chemical action (due ~or example to fumes 7 '1 from the batteries as explained above)could cause the formation B 1¦ of non-conductive layers on the switch contacts. The useful 9 ¦¦ life of light bulbs is affected by electrical shock caused an I
I inrush current generated by the activation of the switch. The 11 ;llight bulbs are also affected by various mechanical shocks 12 which are frequent when the flashlight is used in a rough 13 ¦environment. For example a flashlight bulbs frequently damaged 14 when the flashlight is dropped. Finallylthe flashlight linterconnecting elements are susceptible tollong term chemical 16 'degradation as well as mechanical wear and tear.
17 In U~S. Patent No.~,333,129 a hand-held flashlight is 18 ,Idisclosed in which two identical batteries disposed end-to-end l9 I'lare physically and electrically sep~rated by a separator plate.
~Switching meanQ are provided to couple the batteries in a 21 ,common electrical circuit.
22 ` In U.S. Patent No. 1,974,294 a device is disclosed 23 Icomprising two separate flashlights connected by a hinge which 24 , allows the flashlights to be oriented either side-by-side to produce two parallel ligh~ beams or end-to-end to produce two 26 beams directed in opposite directions.
27 In U.S. Patent No. 3,299,262 a flashlight is 28 disclosed which can be coupled to an external battery pack to 29 provide a high intensity light beam if desired.
l None o~ these references disclose a structure with ;31~2~323~

the advantage-: described below.
An rJbjective of the present invention is to provide a flashlight with a backup system provided to insure the operation therecf in emergency conditions.
~nother objective is to provide a flashlight which can be constructed economically, by the use of relatively inexpensive materials, and which in the long run is relatively inaxpensive to operate.
A further objective is to provide a flashlight with a long shelf life to insure that it is operational even if used infrequently. Briefly a flashlight constructed in accordance-with this invention comprises a housing in which two different electrical systems are provided for generating light beams. Both the first and the second system include a power source such as one or more batteries, a light bulb and a switch for selectively activating the respective system.
Preferably, the first or primary system has relatively inexpensive components which are expected to be replaced o~ten, especially if the flashlight is used frequently. The second, or backup system comprises high performance components with relatively long shelf life, in the order of ten years or more. Preferably the two systems are independent and completely separated so that the failure of one system has no effect on the performance of the other system.
Accordingly, one aspect of the invention provides a hand-held flashlight comprising: a flashlight head with a transparent lens and sidewalls defining a first cavity, a flashlight body with at least one longitudinal wall and a second cavity, housing interconnecting means for interconnecting said body and head to form a common enclosure, a primary electrical system disposed in said enclosure for generating a primary beam through said lens, a b a c k u p electrical system disposed in said enclosure and separate from said primary electrical system for generating a backup light beam through said lens, said backup electrical system comprising a backup battery disposed in said first cavity, : L2~3~3~

- 3a -and activation means for selectively activating said primary and backup systemsO
Another aspect of the invention pro~ides a hand-held flashlight comprising: a flashlight head with a transparent lens and sidewalls defining a first cavity, a flashlight body with at least one longitudinal wall and a second cavity, housing interconnecting means for interconnecting said body and head to form a common enclosure, a primary electrical system disposed in said enclosure for generating a primary beam through said lens, a b a c k u p electrical system disposed in said enclosure and separate from said primary electrical system for generatiny a backup liyht beam through said lens; said backup electrical system comprising a power source, a light source and sw.tch means for energizing said backup electrical system, a light bulb assembly for holding said light source and said switch means, and activation means for selectively activating said primary and backup systems.
A further aspect of the invention provides a fla~hlight comprising: a housing consisting of a head, and a body and means for connecting said head and said body in a mating relationship, a first electrical system completely disposed in said head, said first electrical system remaining intact when the body and head are separated for generating a first light beam, and a second electrical system substantially disposed in said body for generating a second light beam emitted through said head.
A still further aspect of the invention provides hand-held flashlight comprising: a flashlight head with a transparent lens and sidewalls defining a first cavity, a flashlight body with at least one longitudinal wall and a second cavity, housîng interconnecting means for interconnecting said body and head to form a common enclosure, a primary electrical system disposed in said enclosure for generating a primary beam through said lens, a backup electrical system disposed in said enclosure and separate from i`, ~IB' ''i ~2~3~3~

- 3b -said primary electrical system for generating a backup light beam; said backup electrical system comprising a lower source, a light source and coupling means for selectively connecting said power source to said light source, an assembly removably disposed in said first cavity, said assembly including said power source and said light source, said coupling means being arranged and constructed to activate said backup system as said assembly is inserted into and removed from said first cavity, and activation means for selectively activating said primary and backup systems.
Embodiments of the invention will now be described, by way of example, with reference to the accompanying drawings, in which:
Figure 1 shows an isometric view of a flashlight constructed in accordance with an embodiment of the invention;

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l l 1 I Figure 2 shows a side view of the flashlight of 2 I Figure l;
3 , Figure 3 shows an exploded view of the flashlight of 4 ~ Figure l;
Figure 4 shows a top view of a light bulb assembly 6 , for the flashlisht of ~igure 1;
7 I Figure 5 shows a side view of the light bulb of 8 IFigure 1;
9 I Figure 6 shows a front view of the light bulb of Figure l; and 11 ~igure 7 is a somewhat schematic view of the two 12 lindependent electrical systems disposed within the flashlight 13 of ~igure 1.
14 DETAILED _ESCRIPTION OF THE INVENTION
A somewhat preferred embodiment sh~11 now be 16 described in conjunction with the drawings. The drawings 17 illustrate a hand-held flashlight 8 with a housing ~ having 18 jtwo mating sections 12 and 14. Section 12 may be termed the 19 ~head of the 1ashlight while the second section 14 may be ~ termed its body. The flashlight body is generally elongated and 21 ~is forme~ of a first longitudinal surface 16 which has an 22 lapproximately semicircular cross-sectlon and a relatively flat 23 longitudioal section 1~. A pushbutton 20 is provided toward a 24 front end of surface 16. As shall be described in more detail ~below, the pushbutton 20 may be used to activate the primary 26 electrical system of the flashlight ~Q. At least a portion of 27 cylindrical surface is serra~.ed as at 22 to provide a non-slip 28 surface. Alternatively a serrated or knurled element made of a 29 different colored material may be imbedded in surface 16. The whole body 12 is ergonomically shaped so that an operator can . .
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lZ93Z31 1 jhold the flashlight comfortably with the thumb resting near 2 ''pushbutton 20 for its activation. The head and body each 3 include a cavity which forms a common enclosure when the two 4 sections are joined.
S i The flashlight head 12 is generally square or ~ ,rectangular and has larger overall cross-sectional dimensions 7 ;than the body 14 for holding the secondary electrical system.
8 IThe head 1~ has a front lens 24 made of a transparent material 9 ,to allow light to pass therethrough. The flashlight head also has a sidewall 26 corresponding to body surface 18, on which 11 sidewall there is provided a slide switch 28. As described in 12 more detail below, the slide switch 28 activates the secondary 13 electrical system of the flashlight 10. Adjacent to the slide 14 switch and slightly forward to it there ijs a relatively small indicating window or other means 30 providedlto show the status 16 of the secondary electrical syster~
17 Flashlight housing 10 is preferably made of a high-18 ,impact plastic material which is relatively immune to normal 19 ,chemical degradation. The body 14 is provided with an enlarged portion 32 which provides a gradual change between head 12 and 21 ,'the remaining portion of body 14. Portion 32 is terminated 22 with a cylindrical neck 34 with a plurality of slanted exterior 23 'grooves 36. The head is similarly provided with lLps 38. The 24 lips 38 are disposed on an inner wall of the head 12 and are arranged for engagement with grooves 36. Thus grooves 36 and 26 lips 38 provide a means of interlocking the head and body 27 sections of the housing 10. For closing the housing the t~o 28 sections are brought into an axial alignment with one lip 38 29 being adjacent to an openning 40 of groove 36. The two sections are then moved toward each other and the head is ~ 1 ~2~23~

1 ,itwisted clockwise until lip 38 comes to rest against wall 42.
2 Neck 34 is provided with a ring shaped gasket 44 which is used 3 ~Ito seal the interior of the flashlight housing. The gasket is 4 lmade of a resilient materi~l such as a synthetic rubber which iurges the two housing sections axially away from each other.
6 '~Thus when the two housing sections are interlocked as described 7 llabove, the housing is sealed in a water- and air-tight manner.
8 I As shown in Figure 2, the body 14 houses two or more 9 jibatteries 46. One of the batteries is in contact with a spring l¦4B secured to a rear wall 50 of the body 14. A conductive strip 11 l52 extends from spring 4~ to a switching mechanism 54 secured 12 bel~ow flat surface 18. The switching mechanism is activated 13 l,by pushbutton 20 as described below.
14 , Refering now to Figures 3-6, w~thin head 12 there is provided a light bulb assembly 56 and a reflector 58. The 16 reflector 58 ls permanently secured to the inner walls of the 17 Ihead 12 and has surface 60 coated with a reflective material.
18 Reflector 58 is also provided with two cylindrical holes 62 and 19 164. 5ur~ace 60 is shaped to capture and direct light from a `light bulb extending from hole 62 in a primary light beam 21 through transparent lens 2~. Lens 24 may be provided with a 22 ,Itransparent cylindrical wall section 66 for concentrating the 23 Iprimary light beam. The inner wall of hole 64 is cylindrical 24 ¦and it terminates in a necked down section 68 for generating a 'backup light beam described below. A projection 70 extends 26 rearwardly toward the housing body 14 and it cooperates with 27 ,the inner walls 72 of the head 12 to engage light bulb assembly 28 56 in a friction fi~. Thus the assembly 56 may be removed from 29 Ithe head if desired.
Assembly is provided with two cylindrical depressions ~ 93~

1 ,j74 and 76 for holding a primary and a backup light bulb 78 and 2 'l80 respectively. As shown in Figure 4, assembly 56 also 3 ~includes an open chamber 82 defined by two upright walls 84, 4 B6, assembly sidewalls 88, 90 and a bottom wall 92. This jchamber 82 is provided for holding a secondary or backup 6 ;battery 94.
7 .¦ Mounted on upright wall 84 there is a conductive 8 .strip 96 with a terminal surface 98. This strip extends along 9 the inner surface of wall 84 along the bottom wall 92 and up on wall 86 until it reaches depression 74 to provide a first 11 central connection for bulb 78. Another strip 99 can be seen 12 partially in Figure 5 and also extends within the assembly to 13 depression 74 to form a second electrical connection for bulb 14 7~. When flashlight is assembled, surfacel98 comes into 'electrical contact with one of the batteries,46 and strip 99 is 16 connected by electrical connection means to switching means 54.
17 I Within chamber 82 there are provided two clips 100, 18 ,102 which hold battery 94 by its terminals. A strip 104 extends 19 Ifrom clip 100 to a position adjacent to the inner end of depression 76, as shown in Figure 5. A small spring 106 is 21 'secured to strip 104 to provide a first or central connection 22 jfor the secondary bulb 80. A second strip lOB extends from clip 23 102 to a first ~erminal of a reed switch 110 mounted on the 24 outside of assembly 56. A secGnd terminal of the reed switch !is connected to a conductive strip 112 which leads ~o and forms 26 a second electrical connection for ~he secondary bulb 80.
27 When assembly 56 is inserted into head 12, bulb 78 is 28 disposed within 62 so that its output is reflected outwardly 29 through lens 24. Similarly bulb 80 extends into hole 64 so that light generated by this bulb is reflected by wall 64. A

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1, 1 light guide 116 in the form of a narrow strip of transluscent 2 Imaterial extends from the necked down portion 68 to the 3 ,Isidewall 28 of head 12. The guide captures a very small 4 'portion of the light generated by bulb 80 and transmits it ,outwardly to provide an indication that the secondary bulb 80 S 'has been activated.
7 'I Switch 28 mounted on head 12 preferably includes a 8 ,'magnet 115 positioned so that as the switch 28 is between a 9 ifirst and a second position, the magnet selectively opens and Icloses the reed switch 110 on assembly 56.
11 , The operation of the flashlight shall now be 12 described in conjunction with Figure 7 which is a somewhat 13 stylized diagram of the various electrical components of the 14 ',invention. As can be seen in Figure 7 t~e flashlight is provided with two completely independent el~ctrical systems.
16 The first or pri.mary system consists of batteries 46, switching 17 means 54, light bulb 78 and interconnection elements including 18 strips 52, 99, and 96, as well as spring 48. The batteries may 19 Ibe relatively inexpensive type C zinc-carbon or alkaline ,batteries.
21 Similarly bulb 78 may be relatively inexpensive bulb 22 Iwith a short useful life~ Switching means 54 may be a 23 mechanical push-on, push-off switch activated by pushbutton 20.
24 This system is the primary system which is normally used to generate a light beam from bulb 78 by the selective activation 26 of pushbutton 20.
27 The secondary or backup system consists of battery 28 94, reed switch 110 activated by magnet 116 operated by slide 29 switch 28, bulb 80 and interconnecting strips 104 and 108.
Battery 94 is preferably a ~attery of the type which has a very ~'~9323~

1 ,long shelf life, such as a lithium battery. The switching 2 'means provided for the system is also a high performance 3 component which is not affected by chemical fume~ or other 4 environmental factors and therefore can be expected to operate Ifor ten years or more even if it is used relatively 6 linfrequently. Finally bulb 80 is also preferably a high 7 performance, long life component with a useful life of 8 thousands of hours. This second system is activated for 9 relatively short time periods, and only when the primary system has failed. Indicator 30 is provided to remind the user that 11 the backup, rather then the primary system, is in operation, 12 and that the primary system needs servicing.
13 Obviously numerous modifications may be made to the 14 invention without departing from its scoqe as defined in the appended claimsO

_g_

Claims

1. A hand-held flashlight comprising:
a flashlight head with a transparent lens and sidewalls defining a first cavity;
a flashlight body with at least one longitudinal wall and a second cavity;
housing interconnecting means for interconnecting said body and head to form a common enclosure;
a primary electrical system disposed in said enclosure for generating a primary beam through said lens;
a backup electrical system disposed in said enclosure and separate from said primary electrical system for generating a backup light beam through said lens, said backup electrical system comprising a backup battery disposed in said first cavity; and activation means for selectively activating said primary and backup systems.

2. A flashlight according to claim 1, further comprising a reflector disposed in said head for reflecting said primary light beam.

3. A flashlight according to claim 1, wherein said primary electric system comprises a primary power source, a light source and coupling means for selectively connecting said power source to said light source.

4. A flashlight according to claim 3, wherein said primary power source comprises a battery disposed in said second cavity.

5. A flashlight according to claim 3, wherein said light source comprises a light bulb disposed in said first cavity.

6. A flashlight according to claim 3, wherein said coupling means comprises a switch disposed in said second cavity and operated by said activation means, and a plurality of conductive strips interconnecting said light source, said primary power source and said switch.

7. A flashlight according to claim 6, wherein said activation means comprises a pushbutton mounted on said longitudinal wall.

8. A flashlight according to claim 1, wherein said backup electric system comprises said backup power source, a light source and coupling means for selectively connecting said power source to said light source.

9. A flashlight according to claim 8, wherein said light source. comprises a light bulb disposed in said first cavity.

10. A flashlight according to claim 8, wherein said coupling means comprises a switch disposed in said first cavity and operated by said activation means, and a plurality of conductive strips interconnecting said light source, said backup power source and said switch.

11. A flashlight of claim 10, wherein said activation means comprises a sliding member mounted on one of said sidewalls.

12. A flashlight of claim 11, wherein said switch is a reed switch and said sliding member includes a magnet for operating said reed switch.

13. A flashlight according to claim 8, further including an indicator for indicating that the backup system has been activated.

14. A flashlight according to claim 13, wherein said indicator comprises a strip of translucent material having one disposed near the backup light and terminating at said sidewall.

15. A flashlight according to claim 1, wherein said primary and backup systems comprise primary and backup batteries respectively, said backup batteries having a shelf life which is substantially longer than the shelf life of said primary batteries.

16. A hand-held flashlight comprising:
a flashlight head with a transparent lens and sidewalls defining a first cavity;
a flashlight body with at least one longitudinal wall and a second cavity;
housing interconnecting means for interconnecting said body and head to form a common enclosure;
a primary electrical system disposed in said enclosure for generating a primary beam through said lens;
a backup electrical system disposed in said enclosure and separate from said primary electrical system for generating a backup light beam through said lens; said backup electrical system comprising a power source, a light source and switch means for energizing said backup electrical system;
a light bulb assembly for holding said light source and said switch means; and activation means for selectively activating said primary and backup systems

17. A flashlight according to claim 16, wherein said assembly includes a chamber for holding said power supply.

18. A flashlight according to claim 17, wherein said power supply is a lithium battery.

19. A flashlight comprising:
a housing consisting of a head, and a body and means for connecting said head and said body in a mating relationship;
a first electrical system completely disposed in said head, said first electrical system remaining intact when the body and head are separated for generating a first light beam; and a second electrical system substantially disposed in said body for generating a second light beam emitted through said head.

20. A hand-held flashlight comprising:
a flashlight head with a transparent lens and sidewalls defining a first cavity;
a flashlight body with at least one longitudinal wall and a second cavity;
housing interconnecting means for interconnecting said body and head to form a common enclosure;
a primary electrical system disposed in said enclosure for generating a primary beam through said lens;
a backup electrical system disposed in said enclosure and separate from said primary electrical system for generating a backup light beam; said backup electrical system comprising a lower source, a light source and coupling means for selectively connecting said power source to said light source;
an assembly removably disposed in said first cavity, said assembly including said power source and said light source, said coupling means being arranged and constructed to activate said backup system as said assembly is inserted into and removed from said first cavity, and activation means for selectively activating said primary and backup systems.