Abstract:
A flashlight particularly useful by safety personnel such as a firefighter and capable of operation with rechargeable battery means or non-rechargeable battery means. The flashlight includes a one-piece plastic casing having a tubular body portion defining a battery compartment and a right angled head portion in which a light bulb is mounted. The battery compartment is closed by an end cap on which electrical conductive means is mounted to form a part of the battery circuit when non-rechargeable batteries are placed in the compartment. A plurality of charging contacts are mounted on the rear wall of the body portion of the flashlight for enabling rechargeable batteries to be recharged while in the compartment. The charging contacts are recessed within the rear wall of the battery compartment so that they can not be engaged by non-rechargeable batteries within the compartment. This prevents the non-rechargeable batteries from being damaged if the flashlight were inadvertently placed into a charging unit with non-rechargeable batteries in the compartment. The circuitry connecting the batteries to the light bulb includes uniquely structured elements which are quickly and easily connected together to facilitate assembly of the flashlight.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    This invention relates generally to flashlights and more particularly to a flashlight of novel construction especially useful by firefighters and other safety personnel working in hazardous environments.  
           [0002]    There are many known flashlights of various designs, sizes, and configurations, but few of those are specially designed for use in hazardous environments. None of those adequately satisfies the requirements for flashlights operating as firefighting equipment. For example, a light used by firefighters must be durable and impact resistant, and must survive drops of up to about thirty feet. It must be temperature resistant and waterproof. It must produce a high intensity light output to cut through smoke, fog, and dust. The light needs to be constructed in a way that it meets UL safety requirement in the United States and Canada and Cenelec requirements in foreign markets. In spite of these severe operating requirements, the light must still be portable and lightweight and easily attachable to the protective clothing or firefighting equipment worn by the firefighter so that the light does not impose any excessive weight on the firefighter and the firefighter has both hands free for other purposes. Because the firefighter often wishes to hold a light in his hand, the light must have a comfortable grip which does not cause the hand or arm of the firefighter to tire.  
           [0003]    The hazardous environment in which a firefighter&#39;s light is to be used demands that the light have an adequate power source for lighting the bulb over an extended period of time so that the firefighter is not deprived of a source of light while in a smoke filled, burning building. To enhance the usefulness of the flashlight, it should be operable with either rechargeable batteries, which can be quickly recharged, or non-rechargeable batteries, both of which should be quickly and easily replaceable within the battery housing. In addition, the non-rechargeable batteries, when in the battery housing, should be completely isolated from the recharging circuit so that the non rechargeable batteries are not destroyed if the flashlight is inadvertently placed onto a charger unit with the non-rechargeable batteries therein. Otherwise, the non-rechargeable batteries may explode, not only causing damage to the flashlight but also possibly injuring the firefighter himself.  
           [0004]    While the specialized flashlight must satisfy all these requirements for operation under very severe and hazardous conditions, to be accepted commercially the light must still be manufactured and assembled in a way which minimizes cost.  
           [0005]    The firefighters flashlight of the invention described hereinbelow was developed with those requirements in mind.  
         SUMMARY OF THE INVENTION  
         [0006]    Accordingly, the primary object of this invention is to provide a novel flashlight particularly adapted for use in severe hazardous conditions, such as use by a firefighter, and capable of satisfying the requirements noted above.  
           [0007]    Still another object of the invention is to provide a novel firefighter&#39;s light which is portable, lightweight, small in size, durable and operable with a rechargeable battery pack or non-rechargeable batteries, both of which are quickly and easily replaced within the battery compartment.  
           [0008]    Still another object of the invention is to provide the above novel flashlight in which the non-rechargeable batteries, when in the battery compartment, are isolated from the recharging circuit and can not be destroyed if the flashlight is inadvertently placed into a charging unit. The rechargeable battery pack and the non-rechargeable batteries fit securely and snuggly in the battery housing, but are quickly and easily replaceable when necessary. The rechargeable battery pack has contacts on one side thereof which engage against the charging contacts extending through a recessed portion of the rear wall of the battery housing for recharging the battery pack when necessary. When non-rechargeable batteries are placed within the battery housing, they do not engage the recharging contacts but rather make electrical connection through a conductive pad mounted on the bottom cap of the battery housing. In this way, the non-rechargeable batteries are isolated from the recharging contacts.  
           [0009]    Another object of the invention resides in the provision of the above novel flashlight in which the bulb containing head compartment is at right angles to the battery compartment and in which the electrical components connecting the batteries to the bulb are all quickly and easily assembled through push fits without requiring any separate wires and soldering connections. This greatly reduces the assembly time and therefor reduces cost.  
           [0010]    A further object of the invention resides in the provision of the above flashlight in which all the various components of the flashlight are secured snugly in place to ensure proper and continued operation of the flashlight under the, abusive handling in severe and dangerous conditions experienced by a firefighter.  
           [0011]    Other objects and advantages of the invention will become apparent from reading the detailed description of the invention which follows, wherein reference is made to the accompanying drawings. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0012]    [0012]FIG. 1 is a front elevation view of the novel firefighter&#39;s flashlight of the invention shown at about three-quarters its actual size;  
         [0013]    [0013]FIG. 2 is a side view of the flashlight of FIG. 1 taken along line  2 - 2  of FIG. 1;  
         [0014]    [0014]FIG. 3 is a fragmentary sectional view of the flashlight taken along line  3 - 3  of FIG. 1;  
         [0015]    [0015]FIG. 4 is a fragmentary sectional view of the flashlight taken along line  4 - 4  of FIG. 3;  
         [0016]    [0016]FIG. 5 is a fragmentary sectional view taken along line  5 - 5  of FIG. 4;  
         [0017]    [0017]FIG. 6 is an enlarged front perspective view from the open of the head portion of the flashlight;  
         [0018]    [0018]FIG. 7 is a fragmentary sectional view taken along line  7 - 7  of FIG. 1;  
         [0019]    [0019]FIG. 8 is a bottom view of the flashlight taken along line  8 - 8  of FIG. 1;  
         [0020]    [0020]FIG. 9 is an exploded front perspective view of the flashlight illustrating the various components thereof;  
         [0021]    [0021]FIG. 10 illustrates a right battery spring at about twice its actual size;  
         [0022]    [0022]FIG. 11 is an upper end view of the right batter spring taken along line  11 - 11  of FIG. 10;  
         [0023]    [0023]FIG. 12 illustrates the left battery spring at about twice its actual size;  
         [0024]    [0024]FIG. 13 is an upper end view of the left battery spring taken along line  13 - 13  of FIG. 12;  
         [0025]    [0025]FIG. 14 illustrates the positive contact coil spring at about four times its actual size;  
         [0026]    [0026]FIG. 15 is a view of the positive contact spring taken along line  14 - 14  of FIG. 12;  
         [0027]    [0027]FIG. 16 is a negative contact coil spring illustrated at about twice its actual size;  
         [0028]    [0028]FIG. 17 is a perspective view of the rechargeable battery pack illustrating the charging contacts on the rear wall of the battery pack;  
         [0029]    [0029]FIG. 18 is a top perspective view of the charger assembly used with the flashlight of FIG. 1 for charging the rechargeable battery pack contained therein;  
         [0030]    [0030]FIG. 19 is a top plan view of the charger assembly taken along line  19 - 19  of FIG. 18; 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0031]    Referring now to the drawings the novel flashlight  20  of the invention includes a one-piece, rigid, plastic casing  22  having an elongated generally rectangular lower tubular body portion  24 , with an enlarged base  25 , defining an internal battery receiving compartment  26 , the bottom open end of which is normally dosed by a bottom cap assembly  28  which fits within base  25 . Casing  22  also includes an upper head portion  30  connected at a right angle to the body portion  24  having an outer generally cylindrical wall  31  defining an open ended bulb mounting compartment  32 , which is normally closed by a head cap assembly  34 . Battery compartment  26  is separated from bulb compartment  32  by a transverse wall or platform  36  integrally molded to the walls forming body portion  24 .  
         [0032]    A bulb  40  is mounted within compartment  32 , a power source in the form of rechargeable NiCad battery pack  42  or four non-rechargeable C cell alkaline batteries  44   a ,  44   b ,  44   c , and  44   d  mounted within battery compartment  46 , provide power to bulb  40  through circuitry including left positive battery spring  46 , right negative battery spring  48 , and a push button operating switch assembly  50  mounted on the side of wall  31 . The way in which bulb  40  is mounted within compartment  32  and the circuitry by which it receives power from battery terminals  46  and  48  will be described later.  
         [0033]    As mentioned already, the flashlight  20  may be advantageously powered by the rechargeable battery pack  42  (FIGS. 9 and 17) or by the non-rechargeable alkaline cells  44   a, b, c,  and  d  (FIG. 9). The way in which those powered sources are selectively mounted within the battery compartment  26  will now be described.  
         [0034]    As shown in FIGS. 3, 4, and  9 , the bottom cap assembly  28  includes a bottom cap  52  having a bottom wall  54  formed as part of a lower, generally rectangular flange  56  and a smaller generally rectangular upper flange  58  having a recess therearound which receives an O-ring  60 . A hard resilient foam-insulating pad  62  is secured on top of wall  54  and an electrically conductive metal fabric material  64  is secured on top of pad  62 . As shown in FIGS. 3 and 4 flanges  46  and  58  fit into correspondingly shaped bores at the open end of base  25  and the cap is held in place by a pair of shoulder screws  66  which pass through openings in side lugs  68  on the cap and thread into threaded openings provided in side lugs  70  in body portion  24 .  
         [0035]    As shown in FIGS. 9 and 17, the battery pack  42  is of generally rectangular configuration, and includes four NiCad batteries wrapped within an insulating sleeve and mounted within an insulating spacer  43  at its lower end. Pack  42  has positive and negative output terminals  72  and  74 , respectively, at its upper end  76  for engaging positive and negative spring terminals  46  and  48 , respectively, when the pack is mounted within compartment  26 . The length of the pack from its upper end  76  to the bottom end  78  of spacer  43  which engages against the conductive surface  64  of resilient pad  62  is approximately equal to the length of compartment  26  from surface  64  to the bottom face  37  of platform  36  so that the pack is retained within compartment  26  so as to ensure continued operation and minimize any damage thereto during use. A plurality of recharging spring contacts  80 ,  82 , and  84  are fixed at the bottom of the rear wall  85  of pack  42 , the spring contacts engaging against the recharging spring contact buttons  86 ,  88 , and  90 , respectively, mounted within recesses  92 ,  94 , and  96 , respectively, provided at the rear wall  91  of the body portion  24  and base  25 . The recesses extend outwardly from the inside face  98  of wall  91  and are separated by small vertical ribs  100  and  102 , the inside faces of which are in line with face  98  of wall  91 . As shown in FIGS. 3, 4, and  5  the inside contact surfaces of buttons  86 ,  88 ,  90  are located within recesses  92 ,  94 , and  96  below the plane of face  98  and the inside surfaces of ribs  100  and  102 . Similarly, the outer contact faces of buttons  86 ,  88 , and  90  are positioned within recesses  104 ,  106 , and  108  defined by the aligned external faces of rear wall  91  and external ribs  110  and  112 .  
         [0036]    Battery spacer  43  includes a flange  117  which has a predetermined tapered configuration on one side  118  which conforms to the same configuration on the inside face  119  of left side wall  120  of body portion  24 . This ensures that the pack can be inserted into the compartment  26  in only one way and in proper orientation so that the spring contact fingers  80 ,  82 , and  84  properly engage against buttons  92 ,  94 , and  96 . Flange  117  also is sized so that it engages snugly against the walls of compartment  26  to hold the pack in place against lateral movement within the compartment. Thus, not only is the pack  42  retained in place against any significant longitudinal movement between the top of pad  32  and the bottom face  37  of wall  36 , it is also restrained against lateral movement by the snug fit between flange  117  and the inside faces compartment  26 .  
         [0037]    The NiCad battery pi  42  is designed to supply two hours of burn time. It can be recharged in about one hour by placement in a charging unit  121  illustrated in FIGS. 18 and 19.  
         [0038]    When desired, instead of using battery pack  42  in the flashlight, four non-rechargeable C-cell alkaline batteries  44   a ,  44   b ,  44   c , and  44   d  may be used. The calls are placed into the compartment  26  in two rows as shown in FIG. 9 with the positive and negative electrodes of batteries  44   a  and  44   c  engaging against battery spring contacts  46  and  48 , respectively, and the cap assembly  28  is again tightened in place. The negative electrode of cell  44   b  and the positive electrode of cell  44   d  engage tightly against the conductive metal fabric  64  to complete the electrical circuit from one row of batteries to the other. The batteries fit within the walls of body portion  24  defining compartment  26  so that the inside face  98  of rear wall  91  and the inside faces of ribs  100  and  102  prevent the cells  44  from engaging against the recessed contacts  86 ,  88 , and  90  which are part of the recharging circuit. This construction and arrangement provides a very simple way of preventing damage to the cells  44  if the flashlight were inadvertently placed into the charging unit  121  with those cells in compartment  26 . The cells  44  are thus totally isolated from charging contacts  86 ,  88 , and  90  and can not be damaged by any recharging current. The simplicity of this construction and the significant benefit which it provides is a major feature of this invention.  
         [0039]    When the flashlight  20  is powered by the four-C call alkaline batteries  44 , it provides up to five hours of burn time.  
         [0040]    The manner in which bulb  40  is mounted within compartment  32  and the circuitry by which power id delivered from battery springs  46  and  48  to bulb  40  will now be described. A tubular socket  120  extends forwardly from the rear wall  122  of head portion  30  and has a bore  126 . A smaller diameter socket  128  and ribs  130  extend forwardly a short distance from rear wall  122  centered within bore  126 . A small positive contact coil spring  132  (FIGS. 14 and 15) fits within bore  128  and includes an elongated bent end  134  which extends through a slot  136  and then laterally into engagement with an output terminal  138  of on/off switch  140  which is operated by a push button  142  and are part of the switch assembly  50 . The left battery coil spring  46  (FIGS. 12 and 13) has its large coil end mounted within a compartment  150  formed by ribs  152  and shelf  154  on top of platform  36 . The smaller coils extend downwardly through opening  156  in platform  36  into battery compartment  26 . Extending from the large coil end of spring  46  is a terminal wire end  47  of multi-bend configuration which nests within an insulating channel  160  defined by ribs projecting from the wall  122 . Wire end  47  extends through a slot  161  in socket  120  so that its terminal end engages input terminal  139  of switch  140 .  
         [0041]    A negative contact spring  162  (FIG. 16) fits within bore  126  and has its inner end  164  extending laterally from the coils and bent inwardly toward wall  122 . The bent end  164  extends outwardly through a slot  166  in socket  120  so that the inner end of spring  162  can rest against ribs  130  axially spaced from rear wall  122 . The bent end  164  fits into a contact black  168  mounted within an electrically insulating channel  170  extending down to spring housing  172  identical to housing  150 . The negative right battery spring  48  (FIGS. 10 and 11) is mounted within housing  172  and its tapered coiled end extends through opening  174  in platform  36  and down into battery compartment  26 . As shown in FIGS. 10 and 11, the inner terminal wire end  49  of the spring  48  is of a multi-bend configuration and, when in place as shown in FIGS. 3, 4, and  7 , end  49  nests within channel  170  and makes contact with the end  164  of spring  162  within contact block  168 .  
         [0042]    Halogen bulb  40  includes a rear contact  180 , a plug having an outer metal wall  182  formed with a metal flange  184 , and a filament connected at one end to contact  180  and at its other and to a soldered contact on the outer wall  182 . Wall  182  fits within the outer end of spring  162  which engages against flange  184  and the bulb is retained in place within bore  126  by the head assembly  34 . Assembly  34  includes a reflector  190  having a central hub  192  which fits over bulb  40  and engages against flange  184 , a lens ring  194  which fits snug within an escutcheon  196 , lens ring  194  being threaded at  198  to thread on to the threaded open end  200  of head portion  30 . When cap assembly  34  is threaded onto head portion  30 , hub  192  forces flange  184  and plug  182  inwardly, compressing spring  162  and engaging contact  180  with spring  132  thus completing the electrical circuit between the bulb, switch  140 , and battery terminals  46  and  48 . An O-ring  197  seals between lens ring  194  and dreaded head portion  200 .  
         [0043]    The manner in which the electrical circuit is formed is unique and enables the components of the flashlight to be quickly and easily assembled without the need of any separate wiring or soldering connections. The terminal contact ends of battery spring  46  and positive marina  132  are push fits into the contact fingers  138  and  139  of switch  140 . Similarly, the terminal contact ends of battery spring  48  and negative spring  162  are push fits into contact block  168 . Also, the multi-bend configurations of the ends  47  and  49  of springs  46  and  48 , respectively, are nested within electrically insulating channels  160  and  170  to avoid any shorts within the circuit.  
         [0044]    It should be noted that the switch assembly  50  is mounted on the side of the outer wall  31  of head portion  30  and is readily accessible for operation when the flashlight is being held in the right hand of a firefighter. Assembly  50  includes push button  152  and O-ring  202  mounted on the outer end of button  142 , with the push button being slidably retained within the opening  204  on the side of wall  31  by bent over tabs  206  on the inside edge of button  142 . Button  142  operates against the force of spring  208  to actuate switch  140  which is held in place in compartment  32  by switch lock  210  and lock ring  212 .  
         [0045]    Attached to head portion  30  are a belt clip  214  and a slip key ring  216  so that the flashlight may be readily connected to a fireman&#39;s belt or strap or other protective gear, so as to free both hands of the fireman for other uses.  
         [0046]    A pressure relief check valve  220  is mounted in the rear wall of head portion  30  to relieve any buildup of pressure in compartment  32 .  
         [0047]    A locking assembly  224  including a locking strip  226 , lock screw  228 , gasket  230 , and retaining ring  232  may be provided on the top of head portion  30  to lock escutcheon  196  against rotation on head portion  30 .  
         [0048]    Also fixed to rear wall  122  are sockets  234  and  236  for holding spare bulbs for the flashlight.  
         [0049]    A label  238  may be fixed to the inside face of the front wall of the flashlight to indicate the proper orientation of the four C-cell batteries within compartment  26 . A label  240  may be provided on the front wall of the flashlight and a label  242  may be provided on the bottom cap  52  to indicate appropriate information to the firefighter.  
         [0050]    As mentioned previously, when the flashlight  20  containing a battery pack  42  is to be recharged, the flashlight is conveniently placed in the charger  121  illustrated in FIGS. 18 and 19. The charger is usually bolted in place on a flat surface such as a table or a wall and includes circuitry suitable for charging the flashlight. The charger includes a plurality of spring loaded finger contacts  250 ,  252 , and  254  for engagement by contacts  86 ,  88 , and  90 , respectively, when the base portion  25  of flashlight  20  is pushed down into the well  260  of charger unit  121 . As shown in FIG. 8, the rear wall  262  of base  25  is straight while the front wall  264  is slightly curved, thus conforming to the same configuration of the rear wall  256  and front wall  257  defining well  260  of charger unit  121  (FIG. 1) This ensures that the flashlight to be recharged can go into the well  260  only in proper orientation so that contacts  86 ,  88 , and  90  properly engage contact fingers  250 ,  252 , and  254 . A push button switch  268  is mounted on the bottom wall of well  260  and is actuated to a closed position by bottom cap  52  as the flashlight is inserted into well  260 , thus automatically turning the charging unit  121  on to start the recharging cycle. Mounted on each side of well  260  is a spring loaded retaining member  270  including two spaced apart, double tapered retaining clips  272  which release outwardly from well  260  and permit the base  25  of the flashlight to be pushed down into the well when the flashlight is to be recharged. When base  25  is fully seated in well  260 , clips  270  spring back inwardly and lock against tapered surfaces  278  on base  25  on both sides of lugs  70 . In this way during the recharging process the flashlight is locked in place within the charging unit. When the charging cycle is completed, flashlight may be removed from well  260  with one hand merely by pulling the light out of the well, forcing the tapered clips  272  to spring outwardly and thus release the flashlight. This is a very useful convenience, since the firefighter need only use one hand to remove the flashlight while his other hand is available for other uses.  
         [0051]    The foregoing relates to preferred exemplary embodiments of the invention, it being understood that other variants and embodiments thereof are possible within the spirit and scope of the invention, the latter being defined by the appended claims.