Illumination – Self powered lamp – Dome – globe or wire guard or lamp bulb cover
Reexamination Certificate
1999-08-12
2001-05-15
Cariaso, Alan (Department: 2875)
Illumination
Self powered lamp
Dome, globe or wire guard or lamp bulb cover
C362S307000, C362S327000, C362S355000
Reexamination Certificate
active
06231208
ABSTRACT:
BACKGROUND OF THE INVENTION
The present invention generally relates to a lighting device. More particularly, the present invention relates to a portable battery-powered lighting device.
Portable lighting devices, such as flashlights and lanterns, are known which produce a directional beam of light.
FIG. 1
shows the construction of a relatively low-cost flashlight
10
currently marketed by the assignee of the present invention. Conventional flashlight
10
includes a battery housing
12
of a molded plastic construction, which further serves as a handle for holding the flashlight. As shown in
FIG. 1
, battery housing
12
has a generally cylindrical shape with one end having an integrally molded end wall
13
. The open end of battery housing
12
, in which batteries may be inserted or removed, includes external threads
14
for engaging the internal threads
16
of a shroud
18
. Battery housing
12
further includes a slot
20
formed in a side thereof in order to enable a raised portion
22
of a sliding electrical contact
24
to be secured to a switch
26
provided on the exterior of battery housing
12
.
Flashlight
10
further includes a spring
28
that is inserted within the battery compartment defined by battery housing
12
. Spring
28
is provided in contact with the end wall
13
to bias the inserted batteries forward into contact with a positive terminal
30
of a light bulb
32
. Spring
28
further provides an electrical contact to the negative terminal of the rearmost battery inserted into battery housing
12
. A fixed electrical contact
34
is also provided within the battery compartment of battery housing
12
to provide an electrical connection between spring
28
and a moving electrical contact
24
.
Flashlight
10
further includes a bulb holder
36
having internal threads
38
for engaging external threads provided as a negative electrical contact
40
of light bulb
32
. Bulb holder
36
also includes either external threads
42
or a welding surface for securing bulb holder
36
within an aperture
44
provided in an electrical contact shell
46
. With such an arrangement, the negative contact terminal
40
of light bulb
32
is electrically coupled through holder
36
to contact shell
46
. At the same time, with light bulb
32
screwed into bulb holder
36
, positive terminal
30
extends beyond the rearward opening of holder
36
so as to come into contact with a positive terminal of the forwardmost inserted battery. To turn light bulb
32
on and off, switch
26
is slid axially along battery housing
12
thereby moving sliding contact
24
forward and rearward into and out of contact with contact shell
46
.
Flashlight
10
additionally includes a reflector
48
having a central aperture for receiving light bulb
32
such that light emitted from light bulb
32
is reflected in a generally forward direction. A lens
50
is provided across the forward opening of the flashlight as defined by shroud
18
and reflector
48
to protect the light bulb from damage. The lens
50
, reflector
48
, contact shell
46
, light bulb
32
, and bulb holder
36
, which together form a head structure of flashlight
10
, are secured across the open end of battery housing
12
by shroud
18
, which includes a lip at its forward end to prevent lens
50
and the components positioned to its rear from falling out of the forward end of shroud
18
.
Although flashlight
10
represents a relatively low-cost flashlight, it nevertheless includes no less than eleven components. Further, due to the number of potential component interfaces through which water could penetrate to reach the interior of battery housing
12
, flashlight
10
would not be considered a waterproof flashlight.
Although conventional lanterns and flashlights such as that described above are well-suited for brightly illuminating a relatively small area, they are not well-suited for providing wide area illumination like that produced by a lighting device designed for area illumination, such as a table lamp or gas lamp. Such area lamps, however, are not well-suited for directing a beam of light to illuminate an area a considerable distance away. Because of the need in the market for lighting devices that may serve as both a directional light and an area light, various devices have been constructed that will perform both of these functions. In some of these lighting devices, separate light sources and lenses are provided that may be independently activated. An example of one such light is disclosed in commonly assigned U.S. patent application Ser. No. 08/690,287. Because two separate switches or a multi-position switch is required to selectively power the separate light sources, and because separate light chambers and lenses must be integrated within the device, these devices tend to be much more complex, bulky, and expensive.
To provide a less complex and less expensive portable lighting device that may function as both a directional light source and an area light, the assignee of the present invention has previously developed a two-in-one portable lighting device that utilizes a single light source, and hence, a single on/off switch. An example of such a lighting device is disclosed in British Patent No. 2,242,732 B. These lighting devices include a two-part housing in which a first part of the housing contains the batteries, the switch, and the light source, and a second part of the housing includes two separate chambers. The first and forwardmost chamber is a directional lighting chamber, and the second chamber is defined by a cylindrically shaped diffusing lens integrated within the cylindrical body of the second part of the housing. The second part of the housing may thus be slid axially along the first housing to reposition the light source within one of the two light chambers. Thus, a user may use such a lighting device as a directional light by sliding the second part of the housing fully within the first part of the housing such that the light source is pushed through a small opening within a reflector of the directional light chamber. Then, to use the device as an area light, the user may fully extend the first part of the housing such that the light source is removed from the directional light chamber into the area light chamber where the light emitted therefrom is transmitted through the cylindrical diffusing lens. Although these portable lighting devices are less expensive and bulky than the portable lighting devices that utilize two separate light sources, they nevertheless remain relatively complex and expensive compared to a conventional flashlight. Furthermore, because the single light source may only be in one chamber at any one time, the portable lighting device may not be simultaneously used as a directional light source and an area lamp. Therefore, there exists a need for a portable lighting device that may operate simultaneously as an area light and a directional light while being easily manufactured at a significantly lower cost.
SUMMARY OF THE INVENTION
An aspect of the present invention is to provide a portable lighting device that may function as both a directional light source and an area light. Still another aspect of the present invention is to provide a portable lighting device that simultaneously functions as both a directional light source and an area light using only a single light source.
To achieve these and other aspects and advantages, the portable lighting device of the present invention comprises a battery housing, a light source supported at a first end of the battery housing, and a shroud extending outward from the first end of the battery housing circumferentially around the light source, the shroud being formed of a translucent material and having a partially reflective inner surface for reflecting a portion of incident light emitted from the light source in a forward direction while allowing the portion of the incident light to be transmitted through the shroud and dispersed in peripheral directions.
It is an additional aspect of the present invention to provid
Dalton David R.
Lynch Peter F.
Cariaso Alan
Eveready Battery Company Inc.
Welsh Robert W.
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