Flashlight with focal length adjustment means

[0002] The present invention relates to a flashlight, and more particularly to such a flashlight, which has adjustment means for adjusting the focal length of the lamp bulb.

[0003] The focal length of a regular flashlight is adjusted by rotating the rim on the lamp case to move the lens relative to the lamp bulb. This focal length adjustment procedure must be performed with both hands, i.e., with one hand holding the barrel of the flash light, and the other hand rotating the rim on the lamp case.

[0004] It is one object of the present invention to provide a flashlight, which has a focal length adjustment device that can be conveniently operated with one hand to adjust the focal length of the lamp bulb. It is another object of the present invention to provide a flashlight, which has a focal length adjustment device that can be operated with one hand to adjust the focal length of the lamp bulb steplessly. It is still another object of the present invention to provide a flashlight, which has water-sealing means to provide the internal circuit.

[0005] FIG. 1 is an elevational view of a flashlight according to the present invention.

[0006] FIG. 2 is an exploded view of a part of the flashlight according to the present invention.

[0007] FIG. 3 is a sectional side view in an enlarged scale of the front part of the flashlight according to the present invention.

[0008] FIG. 4 is an enlarged view of part A of FIG. 3.

[0009] FIG. 5 is a sectional top view in an enlarged scale of the present invention, showing the focal length adjustment device operated, the lamp complete moved backwards.

[0010] FIG. 6 is similar to FIG. 6 but showing the lamp complete moved forwards.

[0011] Referring to FIGS. from 1 through 4, a flashlight is shown comprised of a metal barrel 1, a lamp case 2, a rim 3, a holder shell assembly 4, a switch 45, and a lamp complete 5.

[0012] The metal barrel 1 comprises an insulative partition board 11 on the middle, a metal rear cap 12, a battery set B mounted in the space defined between the partition board 11 and the rear cap 12, and a button hole 13 at the periphery near the front end thereof The negative terminal of the battery set B is supported on a metal spring (not shown) inside the metal rear cap 12, and electrically connected to the metal barrel 1 through the metal rear cap 12. The positive terminal of the battery set B is inserted through a through hole at the center of the partition board 11. The lamp case 2 is fastened to the front end of the barrel 1. The rim 3 is covered on the lamp case 2 at the front side, having a sealing rubber 33 mounted on the inside to hold a reflector 31 within the lamp case 2 and a lens 32 in front of the lamp case 2. The holder shell assembly 4 is mounted in the front end of the metal barrel 1, comprising a negative pole metal contact plate 43 mounted on the outside at one side and disposed in contact with the metal barrel 1, a positive pole metal contact plate 41 provided at the rear end thereof and disposed in contact with the positive terminal of the battery set B, and a front locating ring 42. The switch 45 is mounted on the holder shell assembly 4, having a positive terminal contact connected to the positive pole metal contact plate 41 of the holder shell assembly 4 by a conductor 46, a negative terminal contact connected to the negative terminal of the lamp complete 5, and a button 451 extended out of the button hole 13 at the metal barrel 1 for operation by hand to close/open the circuit between the positive terminal contact and negative terminal contact of the switch 45. The lamp complete 5 is mounted in the front locating ring 42 of the holder shell assembly 4, having a front cap 51 holding a lamp bulb 52 within the reflector 31, a metal rivet 54 provided at the rear end thereof and connected to the positive terminal contact of the switch 45 by a conductor 55, and a metal spring 53 connected between the positive terminal of the lamp bulb 52 and the metal rivet 54. A conductor 56 connects the negative terminal of the lamp bulb 52 to the negative pole metal contact plate 43 of the holder shell assembly 4. Further, a return spring 50 is mounted around the lamp complete 5 and stopped between the front locating ring 42 of the holder shell assembly 4 and the expanded rear end of the lamp complete 5.

[0013] Referring to FIGS. from 1 through 4 again, the lamp complete 5 comprises a beveled stop edge 57 at the periphery of the expanded rear end thereof, and a backwardly extended flange 58. A focal length adjustment device is installed in the metal barrel 1 around the button 451 for adjusting the focal length of the flashlight. The focal length adjustment device comprises a lower actuating member 48, an upper actuating member 49, and a button 40. The lower actuating member 48 comprises a ring 481 mounted around the button 451 of the switch 45, and an actuating rod 482 extended from the ring 481 and stopped at the beveled stop edge 57 at the lamp complete 5. The ring 481 has a plurality of equiangularly spaced hook holes 483. The upper actuating member 49 comprises a ring 491, and a lever 492 extended from the ring 491. The ring 491 of the upper actuating member 49 comprises a plurality of hooks 493 respectively hooked in the hook holes 483 at the ring 481 of the lower actuating member 48, and a retaining notch 494 on the inside. The button 40 is mounted within the ring 491 of the upper actuating member 49 and supported on the button 451 of the switch 45, having a locating rod 401 engaged into the retaining notch 494. Further, O-rings O are respectively mounted around the button 40, the ring 491 of the upper actuating member 49, the connecting area between the metal barrel 1 and the lamp case 2, and the connecting area between the lamp case 2 and the rim 3. The holder shell assembly 4 and the lamp complete 5 are respectively formed of two symmetrical halves coupled together. The lamp complete 5 is allowed to be moved axially within the holder shell assembly 4, but prohibited from rotary motion relative to the holder shell assembly 4. Various measures can be taken to stop the lamp complete 5 from rotary motion relative to the holder shell assembly 4. For example, the holder shell assembly 4 is made having a flat inside wall matched with the beveled stop edge 57 of the lamp complete 5.

[0014] Referring to FIGS. 5 and 6, turning the lever 492 of the upper actuating member 49 causes the lower actuating member 48 to be rotated leftwards (counter-clockwise) or rightwards (clockwise). Because the actuating rod 482 of the lower actuating member 48 is stopped at the beveled stop edge 57 at the lamp complete 5 and the return spring 50 imparts a backward pressure to the lamp complete 5, rotating the lower actuating member 48 causes the lamp complete 5 to be moved axially forwards or backwards to adjust the pitch between the lamp bulb 52 and the reflector 31, and therefore the focal length of the flash light is relatively adjusted.

[0015] While only one embodiment of the present invention has been shown and described, it will be understood that various medications and changes could be made thereunto without departing from the spirit and scope of the invention disclosed.