Flashlight With Battery Separator

This invention relates to flashlights. More specifically, this invention relates to flashlights with apparatus for the prevention of direct physical and electrical contact between the batteries.

Handheld flashlights with a housing, a plurality of batteries, a lightbulb, and a switch are well known in the art. One problem associated with such flashlights is that there may be a reaction between terminals of batteries in electrical contact, even when there is not a complete circuit, causing corrosion, deterioration of the batteries and possible harm to the flashlight as the batteries age. Certain flashlights, such as that described in U.S. Pat. No. 2,449,568, disclose batteries physically separated and having no direct terminal to terminal contact. However, the batteries are not electrically separated but are only physically separated for other reasons and, therefore, do not solve the problems associated with electrical contact. Other patents such as U.S. Pat. No. 4,151,583 disclose a switch which physically and electrically separates the battery terminals at their normal interface but leave a continuous electrical contact along an outer electrical circuit giving rise to the same problem. U.S. Pat. No. 2,816,215 discloses a folding flashlight which also physically prevents electronic contact along the normal connecting path but does allow continuous electrical connection along an exterior path. Therefore, the inventor knows of no patents which provide a complete physical and electronical separation of the batteries.

A physical and electronical separation of flashlight batteries is created by the installation of a separator plate between the normally connecting terminals of the batteries. The separator plate has conductive material on each side which contacts a terminal of a battery but the conductive materials do not make electrical connection with each other until a switch is placed in its "on" position completing the normal circuit and connecting the conducting surfaces of the separator plate. Means are provided for loading the batteries.

FIG. 1 is a view of the flashlight in cross-section.

FIG. 2 is a view of the flashlight in partial cross-section in position for loading the batteries.

FIG. 3 is a view of one side of the separator plate.

FIG. 4 is a view of the opposite side of the separator plate.

FIG. 5 is a view of the switch in the off position.

FIG. 6 is a view of the switch in the on position.

FIG. 7 is a cross-sectional view of the flashlight along line 7--7 of FIG. 5.

Referring to FIG. 1, the preferred embodiment F of the present invention includes the conventional flashlight structure of a flashlight housing 10, a first battery 12 with a first terminal 12a and a second terminal 12b, a second battery 14 also with a first terminal 14a and a second terminal 14b, a first switch means 16 mounted with the housing 10, a bulb 18 mounted within the housing 10 and circuit means 20 for making an electrical circuit including the second battery 14, the first battery 12, the bulb 18 and the switch 16. The first terminals 12a and 14a have an opposite charge from second terminals 12b and 14b. The first switch means 16 has a first or "on" position, as shown in detail in FIG. 6, which allows electrical communication between the first terminal 12a of the first battery 12 and the second terminal 14b of the second battery 14. When the first switch means 16 is in its second or "off" position, as seen in FIG. 5, electrical communication between the first battery first terminal 12a and a second battery second terminal 14b is prevented. The improvement of the present invention includes a second switch means 22 mounted with the flashlight housing 10 which allows electrical communication between the second terminal 12b of the first battery 12 and the first terminal 14a of the second battery 14 when in a first or "on" position physically and electrically separates the first battery second terminal 12b and the second battery first terminal 14a when in a second or "off" position. Thereby, when the first switch means 16 and the second switch means 22 are in their off positions, the first 12a and second 12b terminals of first battery 12 and the first 14a and second 14b terminals of the second battery 14 are physically and electrically separated and there is no contact between the terminals.

In greater detail, the flashlight F of the preferred embodiment includes the generally cylindrical housing 10 with an exterior wall 10a, an interior wall 10b, a front end 10c and a back end 10d. Mounted with the back end 10d is flashlight cap 24 which is threadedly connected to the housing cylinder 10. A conical spring 26 of a conductive material is placed within the housing 10 so as to rest against the interior base 24a of cap 24. The wide end 26a of the spring makes electrical contact with the cap 24. The narrow end 26b of spring 26 makes electrical contact with the second terminal 14b of second battery 14. A reflector housing 28 is threadedly engaged with front end 10c. Reflector 30 is mounted in reflector housing 28 and is formed with a bulb mount 30a in which bulb 18 is mounted. Bulb 18 has a first contact 18a and a second contact 18b. Contact 18a is in physical and electrical contact with the first battery first terminal 12a. Second contact 18b is in electrical contact with the reflector bulb mount 30a.

Circuit means 20 includes forward strip 32 which is mounted along the housing interior wall 10b and, at its front end 32a, electrically connects to reflector 30 and, at its back end 32b, is adjacent to first switch means 16. Circuit means 20 also includes rearward strip 33 which is mounted along housing interior wall 10b and at its front end 33a is adjacent to first switch means 16 and, at its back end 33b, electrically connects to cap 24.

The first switch means 16 is mounted on and through housing 10. Seen in more detail in FIGS. 5, 6 and 7, the first switch 16 includes a slide plate 35 which is mounted for slideable movement along housing 10 on the exterior wall 10a. The first switch connecting strip 16a is mounted for slideable movement along the housing interior wall 10b. Slide plate 35 and connecting strip 16a are held together and upon the housing by brad 16b which causes them to move simultaneously. Brad 16b is mounted through hole 17 formed in housing 10 which limits the movement of slide plate 35. The connecting strip 16a is of a conductive material and, when the first switch means 16 is in the first or "on" position, as shown in FIG. 6, connects forward strip back end 32b and rearward strip front end 33a of circuit means 20 to form an electrical circuit. When the first switch means 16 is in its second position, as seen in FIG. 5, forward strip back end 32b and rearward strip front end 33a of circuit means 20 are not electrically connected and the circuit is broken. First switch means connecting strip 16a is preferably formed with bend 16c to ensure good electrical contact.

The second switch means 22 includes a separator means 34, mounted within housing 10, physically and electrically separating the first battery second terminal 12b from the second battery first terminal 14a. The separator means 34 includes a separator plate 36 which is made of a non-conductive material, such as a plastic, and has a first side 36a and a second side 36b, as seen in FIGS. 3 and 4 respectively. The first and second sides 36a and 36b of separator plate 36 are substantially covered with a conductive substance by any of the many means well known in the art but, preferably, by gluing of metallic linings 38 and 40 respectively. Although covering substantial portions of the separator plate 36, the metallic linings 38 and 40 do not electrically communicate, as shown in FIGS. 3 and 4. The separator plate 36 may be variously shaped but is preferably of a generally L-shaped form having a leg 36c and a base 36d. At the top of the leg 36c is a cylindrical portion 36e through which runs axle 36f used to mount the separator plate 36 in the housing 10. The metallic linings 38 and 40 each have a portion running along the separator plate leg 36c which is wrapped substantially around the separator plate cylinder 36e. Thereby, a portion, 38a and 40a respectively, of the metallic strips 38 and 40 are in relatively close proximity along the cylinder 36e without touching. Those portions 38a and 40a in proximity are used to make electrical contact between the two metallic linings 38 and 40.

The second switch means 22 in the preferred embodiment is mounted on housing 10 with the first switch means 16 and uses slide plate 35 for moving from a first or "on" position to a second or "off" position. As seen in greater details in FIGS. 5 through 7, the second switch means 22 also includes a second switch means brad 22b which holds a connecting strip 22a and the slide plate 35 to the exterior wall 10a and interior wall 10b respectively through hole 17 and allows slideable movement. The connecting strip 22a, when in its first or "on" position as seen in FIG. 6, connects portions 38a and 40a of metallic linings 38 and 40, thereby completing an electrical circuit from the first side 36a to the second side 36b of the separator plate 36.

The separator plate 36 is mounted within the housing 10 between the first battery second terminal 12b and the second battery first terminal 14a. The metallic lining 38 on the separator plate first side 36a makes physical and electrical contact with the first battery second terminal 12b. The metallic lining 40 on the separator plate second side 36b makes physical and electrical contact with the second battery first terminal 14a. Therefore, when the connecting strip 22a of the switch means 22 is in the "on" position the metallic strips 38 and 40 and the connecting strip 22a provides an electrical connection between the two terminals. The first switch means connecting strip 16a and the second switch means connecting strip 22a are in a generally parallel and non-touching construction as seen in FIG. 7 so that there is no electrical connection between them.

The separator plate 36 is mounted within housing 10 in mounting parts 42a and 42b. Mounting parts 42a and 42b are generally rectangular sheets mounted or formed on the interior wall 10b parallel to each other and extending lengthwise along housing 10. Formed in mounting parts 42a and 42b are mounting slots 44a and 44b, respectively, in which is placed separator plate axle 36f. This allows separator plate 36 to have some motion along the length of housing 10 so as to adjust for movement of batteries 12 and 14 and, also, to have rotational motion about axle 36f for the purpose of loading batteries as explained below.

When slide plate 35 is moved so that first switch means 16 and second switch means 22 are in their "on" position, a complete electrical circuit is formed following a path which may be described by arbitrarily starting at the first terminal 12a of first battery 12 and proceeding along bulb first contact 18a, bulb second contact 18b, reflector hole 30a, reflector 30, circuit means forward strip front end 32a, circuit means forward strip back end 32b, first switch means connecting strip 16a, circuit means rearward strip front end 33a, rearward strip back end 33b, cap interior base 24a, spring wide end 26a, spring narrow end 26b, second battery second teminal 14b, second battery first terminal 14a, metallic lining 40 along separator plate second side 36, second switch means connecting strip 22a, metallic lining 38 along separator plate first side 36a, and first battery second terminal 12b. When the slide plate 35 is in its second or "off" position, the connecting strips 16a and 22a break the circuit at two points between circuit means forward strip rear end 32b and rearward strip front end 33a and between metallic linings 38 and 40 thereby preventing electrical or physical contact between the second battery first terminal 14a and second battery second terminal 14b and first battery second terminal 12 b and second battery first terminal 14a.

To load batteries in the flashlight preferred embodiment F, preferably the cap 24 and the spring 26 are removed from the housing back end 10d. The flashlight is turned to a position, as seen in FIG. 2, whereby the separator plate 36 rotates about axle 36f in mounting slots 44a and 44b to lie between mounting parts 42a and 42b. First battery 12 is inserted into the flashlight F with first battery first terminal 12a touching the bulb first contact 18a. The flashlight is then rotated approximately 180.degree. about its longitudinal axis so that the separator plate will rotate 90.degree. within mounting slots 44a and 44b and the metallic lining 38 will be in contact with the first battery second terminal 12b. Second battery 14 is then inserted into the housing 10 so that the second battery first terminal 14a is in contact with metallic lining 40. The spring 26 is then inserted and cap 24 is threadedly connected to complete the loading of batteries.

The foregoing disclosure and description of the invention are illustrative and explanatory thereof and various changes in the size, shape and materials as well as the details of the illustrated construction may be made without departing from the spirit of the invention.