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(11) | EP 0 265 396 A2 |
| (12) | EUROPEAN PATENT APPLICATION |
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| (54) | A battery-operated portable light emitting scattered and spotted beams of light |
| (57) A portable light (1), adapted for emitting a spotted beam or a scattered beam of
light and having a simple and reliable construction, comprises a body (2), a parabola-shaped
reflective member (3), and a lamp (6) having its bulb (7) placed at the focal point
of the reflector parabola, a refractive sleeve (14) slidingly movable under the action
of a drive means (23) between a first or scattered light position whereat it juts
out around the bulb (7), and a second or spotted beam position, whereat it is retracted
away from the bulb (7), and a plurality of annular ridges (24) formed across the sleeve
(14) exterior to create a Fresnel lens (59). |
[0001] This invention relates to a portable light of the type comprising a body, a parabola-shaped reflective member, and a lamp having its bulb placed at the parabola focus.
[0002] It is well known that lights of the type specified above are required to both illuminate the close proximity of the light, all around it, and objects which may lie at a considerable distance away. That is, to meet the user's demand, it is necessary that the light can provide, on the one side, a scattered beam of light, and on the other side, send forth a long-range spotted beam.
[0003] In conventional lights used heretofore, this ability has been provided by mounting two lamps in the reflective member, one with its bulb located exactly at the focal point of the parabola and another displaced therefrom. These lamps produce respectively a spotted beam and a scattered beam. This prior approach, while serving its purpose, is obviously an expensive and complicated one, both from the constructional standpoint and that of its manipulation. The scattered beam, moreover, is irregular and non-uniform.
[0004] Portable lights have been proposed wherein a single lamp can be shifted between a position whereat its bulb is located exactly at the parabola focus and a position whereat it is removed from the focus. These positions provide respectively a spotted beam and a scattered beam. While being in many ways convenient, this prior approach is still affected by the problem that the scattered beam lacks the uniformity and full coverage that would be desirable, and rather produces halos.
[0005] It is the object of this invention to provide a portable light as indicated which is characterized in that it comprises a refractive sleeve mounted on the reflective member for a sliding movement, under the influence of a drive means, between a first or scattered beam position, whereat it would jut out around the lamp bulb, and a second or spotted beam position, whereat it would be retracted away from the lamp bulb; and a plurality of annular ridges formed across the refractive sleeve exterior to create a Fresnel lens configuration.
[0006] Further features and the advantages of the portable light according to this invention will become apparent from the following detailed description of a preferred embodiment thereof, given by way of illustration and not of limitation with reference to the accompanying drawings, where:
Figure 1 is a part-sectional view of a portable light according to the invention;
Figure 2 is a part-sectional view of the portable light shown in Figure 1, but in a different operating condition thereof;
Figure 3 is a part-sectional view of a detail of the portable light shown in Figure 2, taken along the line III-III;
Figure 4 is a detail view of the portable light shown in Figure 1, taken in the direction of the arrow IV; and
Figure 5 is a part-sectional perspective view of another detail of the portable light shown in Figure 1, taken along the line V-V.
[0007] With reference to the drawing figures, generally indicated at 1 is a portable light according to the invention which includes an elongate body 2 in the direction of a horizontal axis X-X thereof.
[0008] A parabolic reflective member 3 is attached to the body 2 at a forward location thereon, the parabola having an axis X-X. The reflective member 3 is closed on the front by a transparent protective cover 4 and formed with a circular passageway 50 at the parabola apex. A lamp holder 5 extends through the circular passageway 50 which has a chrome-plated surface and, hence, electrically conductive. Threaded into the lamp holder 5 with a threaded metal portion 8a is a conventional lamp 6.
[0009] The lamp 6 has a bulb 7 positioned at the focal point of the parabola, and an opposedly located electric contact 8b.
[0010] The lamp holder 5 is supported on a case 51 housed within the body 2. More specifically, the case 51 has a front wall 52 whereto the lamp holder 5 is mounted by means of a flange 18 thereof, and a tubular extension 53 wherein a seat 10 is formed which extends lengthwise and will accommodate a fixed number of dry batteries, collectively designated 11, e.g. four dry batteries of the so-called "flashlight" type arranged in flanking pairs. These form a power supply for the lamp 6 via a switch 12 and suitable conductors to be discussed hereinafter.
[0011] The body 2 is also formed with a handgrip 13 which extends over the battery compartment 10, from the rear end of the body 2 to a set point behind the reflective member 3.
[0012] The portable light of this invention includes a refractive sleeve 14 in the form of a cylindrical tube with an axis X-X and provided with an outer wall 15 and an inner wall 16 and a free end 14a.
[0013] The sleeve 14 extends through the circular passageway 50 and fits over the lamp holder 5 for sliding movement along the direction of the axis X-X.
[0014] The sleeve 14 has two diametrically opposed projections 19 and 20, respectively an upper one and lower one, which extend in the direction X-X rearwards of the sleeve through respective apertures 21 and 22 formed in the flange 18.
[0015] The sleeve 14 is movable under the influence of a drive means 23 to be described between a first position whereat the sleeve juts out of the circular passageway 50 encircling the bulb 7 and a second position whereat it is retracted away from the bulb, fully inside the circular passageway 50.
[0016] The sleeve 18 is expediently made of a transparent material such as Plexiglas, for example, and formed with annular ridges, collectively designated 24, circumferentially around its outer wall 15.
[0017] The annular ridges 24 formed on the outer wall 15 comprise a first, convex-back middle ridge 54 of greater width, and ridges 55,56,57, and 58 distributed on either sides of the middle ridge 54. In particular, the ridges 55 and 56 are placed on the same side as the free end 14a of the sleeve 14, and the ridges 57 and 58 on the opposite side therefrom.
[0018] The ridges 55 and 56 have a sawtooth profile with a convex back facing in the opposite direction from the middle ridge 54. Likewise, the ridges 56 and 58 have the same profile with the convex back facing away from the middle ridge 54.
[0019] Taken together, the ridges 54,55,56,57, and 58 form a Fresnel lens 59 of the converging type.
[0020] It should be noted that the sleeve 14 has over its inner wall 16 a surface finish 65, as obtained by ball punching, which materializes in a plurality of spherical projections, collectively designated 66, of small size and uniformly distributed over the sleeve inner surface.
[0022] Provided at the free end 14a of the sleeve 14 is instead a surface finish 67 of the glazed type.
[0023] It should be noted that the sleeve 14 has, on its inner wall 16, three longitudinal ridges, lying axially along the sleeve at equiangular intervals, which are all indicated at 25 and serve as guide members for the sleeve 14 movement over the lamp holder 5.
[0024] The drive means 23 for the sleeve 14 comprises a slider 26 which is mounted on the body 2 for sliding movement in the direction of the axis X-X at a location somewhere between the handgrip 13 and the reflective member 3, which slider is adapted to be operated manually.
[0025] The slider 26 has a rigid rod-like appendage 27 directed toward the interior of the body 2 and intended to engage with the projection 19 so as to shift the sleeve 14 from its rectracted position to its jutting-out position against the bias of an elastic means 28 in the form of a spring stretched between the projection 20 and the body 2.
[0026] The portable light 1 of this invention further comprises a snap-action means 29 to stop the sleeve 14 in its retracted position, jutting-out position, and in a plurality of intermediate positions.
[0027] The snap-action stop means 29 comprises a spring-loaded pawl 30 which is carried on the slider 26 and adapted to selectively engage in plural notches, collectively designated 32, which are formed in the body 2.
[0028] It should be noted that the rigid appendage 27 is advantageously made conductive and forms a moving contact 36 for the switch 12, which contact would engage with a fixed contact 37 on the switch 12. The fixed contact of the switch 12 is formed by a first conductive elastic reed 31a and a second conductive reed 31b.
[0029] The reeds, 31a and 31b, are attached to the wall 52, and led electrically to the batteries 11 by conductors to be described.
[0030] The reed 31a is led electrically to a contact 38 whereto a positive pole of the batteries 11 is connected via reed conductors 60 and 61 affixed to the wall 52.
[0031] The reed 31b is led electrically to a contact 39 whereto a negative pole of the batteries 11 is connected via a reed 62 affixed to the wall 52, a lug 18a formed integrally with the externally chrome-plated flange 18, the lamp 6, a reed 63 engaged with the lamp contact 8b, and a reed 64, also affixed to the wall 52.
[0032] The slider 26 is movable farther in the direction X-X by a set distance away from the reed 31 into a position where the appendage 27 disengages from the reeds 31a and 31b and the switch 12 breaks.
[0033] With the switch in said break position, the slider 26 would be held back by a pawl 30 snapping over a ridge 33 which stands proud of the body 2, and a further pawl 34, carried on the slider itself, simultaneously snapping over a further ridge 35, which also stands proud of the body 2.
[0034] The operation of the portable light 1 according to the invention will be next described with reference to a starting condition like that depicted in Figure 1, wherein the slider 26 is in its open switch position and the sleeve 14 is held in its retracted position by the action of the spring 28, at its travel end against the bottom wall 18.
[0035] By manually shifting the slider 26 toward the reflective member, the rod-like appendage 27 is first caused to engage with the reeds 31a and 31b. In that condition, the switch 12 would be closed, the lamp turned on, and the portable light projecting a spotted beam of light.
[0036] In fact, in that condition, the rays of light issuing from the lamp and indicated at R impinge on the parabola-shaped reflective member 3 and all reflected thereby in parallel directions to the axis X-X. Thus, the light rays form a spot type of light beam.
[0037] By further movement of the slider 26, the rod-like appendage 27 is caused to engage with the projection 19, and accordingly, displace the sleeve 14 from its retracted position into its extended position wherein it juts out aall around the lamp bulb.
[0038] In that condition, the light rays issuing from the lamp and indicated at R₁ will radiate from the bulb 7 center out, and pass through the Fresnel lens 59. The rays emerging from the Fresnel lens 59 and indicated at R₂ will lie substantially parallel to one another and perpendicular to the axis X-X.
[0039] In this setting they will impinge on the parabola-shaped reflective member 3. The light rays reflected therefrom and indicated at R₃ will form an angle with the axis X-X and be no longer parallel to the axis X-X. As a result, the light beam issuing from the portable light will be a scattered rather than a spotted one.
[0040] By providing a surface finish with spherical projections uniformly distributed over the sleeve surface, the light rays going through the sleeve are further redirected in several directions, thereby they will impinge on the reflective member from points other than the focal point of the parabola.
[0042] By virtue of the glazed surface finish imparted to the free end of the sleeve, the light rays going through the sleeve will be further scattered, again enhancing the scattered beam effect.
[0043] When the sleeve 14 is instead stopped in an intermediate position to the retracted and extended positions, a mixed light beam can be obtained, i.e. a light beam having intermediate characteristics to those of spotted and scattered beams.
1. A portable light of the type comprising a body (2), a parabola-shaped reflective
member (3), and a lamp (6) having a bulb placed at the parabola focus, characterized
in that it comprises a refractive sleeve (14) mounted for sliding movement under the
influence of a drive means (23) between a first or scattered beam position, whereat
it juts out around the lamp bulb (7), and a second or spotted beam position whereat
it is retracted away from the lamp bulb (7); and a plurality of annular ridges (24)
formed across the refractive sleeve (14) exterior to create a Fresnel lens (59) configuration.
2. A portable light according to Claim 1, characterized in that the annular ridges
(24) comprise a middle ridge (54) of greater width and having a convex back, and sawtooth
ridges (55,56,57,58) with convex backs, distributed on either sides of the middle
ridge (54), with the last-mentioned backs facing away from said middle ridge, thereby
creating a Fresnel lens (59) of the converging type.
3. A portable light according to Claim 2, characterized in that said sleeve (14) has
a surface finish (65) with spherical projections (66) uniformly distributed over at
least part of the outer and inner walls thereof.
4. A portable light according to Claim 3, characterized in that said sleeve (14) has
a surface finish of the glazed type (67) at the free end (14a) thereof.
5. A portable light according to Claim 1, characterized in that it comprises a snap-action
means (29) of stopping the sleeve (14) in said positions and in plural intermediate
positions of mixed beam emission.
6. A portable light according to Claim 3, characterized in that said drive means (23)
comprises a slider (26) mounted within the body (2) for sliding movement and being
manually operated, said slider (26) including an appendage (27) adapted to act on
the sleeve (14) against the bias of an elastic means (28).
7. A portable light according to Claim 4, characterized in that said appendage (27)
is made conductive and forms a moving contact (36) for a lamp (6) control switch (12).
8. A portable light according to Claim 5, characterized in that the snap-action stop
means (29) for the sleeve (14) comprises a spring-loaded pawl (30) carried on the
slider (26) for selective engagement in a plurality of notches (32) formed in the
body (2).