Background of the Invention
1. Field of the Invention
The present invention relates generally to portable lighting devices, and more specifically to a portable lighting device which may be attached to a key having a head of any width.
2. Description of the Prior Art
Lighting devices which attach to keys are well known in the art. For example, U.S. Pat. No. 4,085,315, issued Apr. 18, 1978, and U.S. Pat. No. 4,303,966, issued Dec. 1, 1981, both to Wolter, show such devices. Both of the patents to Wolter show a housing receiving an incandescent bulb, battery, battery cover and spring. The lamp operates when the battery, by way of the battery cover, is depressed against the urging of the spring so as to engage a contact, thus completing the circuit between the battery and the bulb.
Both of the above-mentioned patents to Wolter also disclose a light attachable to a key in a manner, by design, which limits the width of the key head to which the light may be attached.
An additionally significant limitation of the above-mentioned two lights is that the body of the key light extends wider than the width of the key head.
There is a need for a light attachable to a key which accepts a wide variety of key widths, is of a narrow construction for allowing use with most automobile ignition locks, which is sufficiently strong to resist twisting forces which would tend to separate the light and the key, and which provides means to maintain the focus of light para11el with the axis of the key. It is an object of the present invention to provide each of these features in a light attachable to a key, as well any and all other objects enumerated in the present application.
Summary of the Invention
The present invention provides a light attachable to a key having virtually any width head. The key head is clamped between a housing a back plate which are held together by a screw or similar securing device. Supplementing the clamping force between the housing and backplate to hold the key in place is a section of self-adhesive material located between the back plate and key. The housing surface and back plate which engage the key are planar and open on all but one side, thus allowing the key head to overhang three edges of the light. The back plate has a raised shoulder at one end for engaging the top- most portion of a key head. Extending out from the shoulder on the back plate is a notch which fits into a complementary shaped groove in the housing when the light is assembled. This notch and groove combination assists in preventing unwanted rotation of the key out of alignment with the beam of the light.
The internal workings of the light comprise an internal frame which is fitted into a recess in the housing. The frame has recesses for receiving a battery, bulb, switch and internal connections. The switch is of the push button temporary contact type and in one embodiment extends through the upper surface of the housing. A continuous contact is established between one terminal of the battery and one terminal of the bulb. A second terminal of the battery is connected to a contact secured to the frame and held proximate to, but not in touching contact with, the second terminal of the bulb. That portion of the contact proximate to the second terminal of the light bulb is biased against the actuator of the push button switch. When the actuator is depressed the contact is brought into touching engagement with the second terminal of the light bulb, which completes the circuit, and illuminates the light.
In one embodiment of the present invention, a screw driver is provided for operating the screw securing device. The screwdriver is carried in a recess provided in the housing such that when installed in the recess the head of the screwdriver is flush with one side of the housing. A biased retaining tab is provided in the internal frame which engages a portion of the screwdriver when the screwdriver is disposed in the recess for holding the screwdriver in place. Provision of such a screwdriver allows convenient and quick installation of the light onto the key head, removal of the light from the key head, and tightening of the screw securing means.
In a preferred embodiment of the present invention an eyelet of large diameter is provided to allow installation of the light into a wide variety of key carrying chains and rings. Further, the housing back plate and switch actuator are fabricated of a metal. such as aluminum, for greater durability.
These and other features of the present invention will become readily apparent from the following detailed description, taken with reference to the figures of the accompanying drawings.
Brief Description of the Drawings
FIG. 1 is a perspective view of an assembled light according to the present invention attached to a key;
FIG. 2 is a perspective exploded view of a light attachable to a key according to the present invention showing internal detail and assembly of the light; and
FIG. 3 is a side cut-away view of the housing, showing the frame, battery, contact and switch of the present invention.
Detailed Description of the Preferred Embodiment
Referring to FIG. 1, a perspective view of an assembled light 20 attached to a key 22 according to the invention of the present application is shown. The light 20 comprises a housing 24 a frame 26 and a back plate 28.
Housing 24 is preferably rectangular in shape. It has a front surface 30 on which a switch 32 for operating the light is positioned. Housing 24 has a back surface 34 which abuts the head 36 of a key 22 when the light is installed on the key 22. The housing 24 has a bottom edge 38 having a bore 40 therethrough from which a light bulb 42 protrudes. Bore 40 in bottom edge 38 is sized to allow the tip of a light bulb 42 to protrude therethrough. Bore 40 in a preferred embodiment is U-shaped, positioned so that the bottom edge 38 is open at the point where the bore 40 on bottom edge 38 meets the back surface 34. Housing 24 further has a top edge 44 from which a key chain eyelet 46 extends, and two side edges 48 and 50 one of which has a bore 52, in a preferred embodiment, for receiving a screwdriver. The key chain eyelet 46 is preferably an arch-shaped member extending from one side edge 48 to the other side edge 50, with a hollow passage 60 for accepting a key chain therethrough. Front surface 30 is provided with a bore 56 for receiving an actuator 58 of switch 32. In a preferred embodiment the bore 56 and actuator 58 are square- shaped and sized so as to allow depressing of the actuator 58 by a user's thumb or fingertip.
Housing 24 is provided with a means 66 for receiving securing means 68 to secure key 22 between housing 24 and back plate 28. In a preferred embodiment securing means 68 comprises a screw, and means 66 comprises a recessed bore for receiving the head of the screw such that the head lies flush with front surface 30 of housing 24.
The back surface 34 of housing 24 is opened to present the cavity 54 for receiving a frame 26. In a preferred embodiment, cavity 54 has a plurality of ribs 62 running between the front surface 30 and the back surface 34 of housing 24. These ribs 62 engage corresponding channels 64 in frame 26 so as to more effectively secure the frame 26 in the cavity 54.
Frame 26, disposed in cavity 54, defines recesses for receiving a battery 72 a bulb 42 and a plurality of bulb-to-battery contacts 74. The recess in frame 26 for receiving the battery will generally be circular to accept a circular battery, the axis of the recess being perpendicular to the plane of front surface 30. The recess for the bulb 42 preferably has ribbed sides that engage threads on the bulb to better secure the bulb in place. The recesses for the contacts 74 may comprise either channel-like recesses into which the entire contact is fit, or in a preferred embodiment, the recesses comprise one or more rectangular notches into which are fit correspondingly shaped holes 76 located on the contacts 74.
As discussed above, side edge 48 of housing 24 is provided with a bore 52 for receiving a screwdriver. Frame 26, in this embodiment, will have a correspondingly shaped and positioned channel 94 for receiving the screwdriver. Additionally, frame 26 is provided with a biased retaining tab 96 which engages a complementary portion of the screwdriver, when the screwdriver is disposed in the recess, for holding the screwdriver in place.
Back plate 28 is a flat rectangular plate of a size corresponding to that of the housing 24. The back plate is provided with means 80 for receiving securing means 68 to secure the key 22 between housing 24 and back plate 28. In a preferred embodiment, means 80 comprise a circular bore with a helically threaded interior designed to receive the helically threaded end of a screw. Back plate 28 is provided with a raised shoulder 82 at one edge which extends from and perpendicular to the plane of back plate 28. Extending parallel to raised shoulder 82 is tab 84 of a size and shape designed to correspond to the size and shape of channel 70 in housing 24. Back plate 28 is further provided with adhesive material 86 to provide added strength to the clamping force between the housing 24 and back plate 28 exerted on key 22.
Referring in particular to FIG. 3, details of switch 32 are shown. Switch 32 comprises a button-like actuator 58 disposed in corresponding bore 56 in housing 24. Actuator 58 is held in place in bore 56 by a biased contact 72 which biases a flanged collar 88 of the switch actuator 58 against a corresponding shoulder 90 on housing 24. Contact 72 which biases switch actuator 58 is proximate to, but not in touching engagement with, battery 72. Means 92 are provided in the frame 26 to allow touching engagement between the contacts 73 and battery 72 when switch actuator 58 is depressed against the biasing force of the contact 72. When such contact is made a circuit between the battery 72 and light bulb 42 is complete, thus light bulb 42 is illuminated.
The material from which housing 24, frame 26 and backplate 28 are made may vary. In a preferred embodiment of the present invention housing 24 and back plate 28 are fabricated of metallic material such as aluminum or alloy. Also, frame 26 in a preferred embodiment is fabricated of plastic. In other embodiments, the housing 24 and back plate 28 may be of plastic material or frame 26 may be of a metallic material. Likewise, the material from which switch actuator 58 may be fabricated may vary, wherein in a preferred embodiment switch actuator 58 is of a metallic material such as aluminum or alloy other embodiments have switch actuator 58 fabricated of plastic.
To provide improved gripping of the light a plurality of parallel notches or similar contours 98 are provided on front surface 30 of housing 24 and back surface 100 of back plate 28. Generally, notches or contours 98 will extend the width of housing 24 and back plate 28 respectively and in a direction perpendicular to the axis of key 22.
To those skilled in the art to which this invention relates, many changes in construction and widely differing embodiments and applications of the present invention will suggest themselves without departing from its spirit and scope. The disclosure and description herein are purely illustrative and are not intended to be in any sense limiting.