Information
-
Patent Grant
-
6294746
-
Patent Number
6,294,746
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Date Filed
Wednesday, May 17, 200024 years ago
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Date Issued
Tuesday, September 25, 200123 years ago
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Inventors
-
-
Examiners
Agents
-
CPC
-
US Classifications
Field of Search
US
- 200 60
- 200 564
- 200 565
- 200 567
- 200 570
- 200 571
- 200 336
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International Classifications
-
Abstract
A rotary switch and a flashlight incorporating same are described. A cylindrical housing encloses a button-type battery cell and provides a grounded inwardly protruding, inwardly biased resilient wiper. A rotor, movably approximated to the housing, has a generally cylindrical hub defining one or more contact areas on its side surface for selectively electrically connecting a bulb or other device to the battery cell by rotating the rotor relative to the housing. The rotor further defines a retaining tooth which engages a retaining groove on the outer surface of the housing to keep the rotor on the housing. Rotational position is stabilized by cooperation between a the wiper and a contact surface or between the rotor shell and a position key formed on the housing. The rotor hub is configured to house a circuit module for interposing desired electrical functions between the bulb and the battery cell.
Description
THE FIELD OF THE INVENTION
The present invention relates generally to portable electrical devices and battery powered devices and more particularly to miniature flashlights and flashers.
THE BACKGROUND ART
Presently available switches for miniature and multi-function flashlights provide for the selection of a limited number of functions and often require electrical continuity between a battery cap, a battery housing and a substantial portion of the switch housing in order to provide a ground. Consequently, the functions of such devices are limited in number and their cost and weight are greater than would be preferred.
It would be helpful to be able to manufacture lighter, less expensive, more versatile miniature electrical devices such as a multifunction flashlight. Such devices might be made more convenient, more practical and more attractive, as well as more reliable and less expensive, if an improved rotary switch were available.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide an inexpensive, compact, convenient rotary switch for selectively operating a miniature flashlight and especially for a combination of a flashlight with a lantern or flasher.
It is an additional object of the present invention to provide such a switch in a flashlight or similar article which uses metal sparingly and which can be made of mostly transparent materials.
In accordance with these objects and with others which will be described and which will become apparent, an exemplary embodiment of a rotary switch in accordance with the present invention includes a housing, a rotor approximated to the housing, an electrically conductive wiper disposed on the housing, and an electrically conductive contact surface disposed on the rotor. The wiper and the contact surface are movable between a first relative position and a second relative position. An electrical circuit is closed comprising the wiper and the contact surface in series when the wiper and the contact surface are in the first relative position. The electrical circuit is opened when the wiper and the contact surface are in the second relative position. The housing defines an axis of rotation, the rotor being rotatable about the axis of rotation with respect to the housing to provide the first and second relative positions of the wiper and the contact surface. The wiper is confined at an angular position about the axis of rotation on the housing. The contact surface is confined at an angular position about the axis of rotation on the rotor, such that, with rotation of the rotor about the axis of rotation with respect to the housing, the wiper and the contact surface are moved between the first and second relative positions. The wiper and the contact surface when in the first relative position define a thrust axis. The wiper is supported on the housing with respect to the thrust axis, and the contact surface is supported on the rotor with respect to the thrust axis, such that the wiper and the contact surface are urged into mutual electrical contact when in the first relative position. The wiper and the contact surface when in the first relative position cooperate to provide resistance to rotation of the rotor relative to the housing, whereby the first relative position is stabilized.
Also in accordance with the objects of the present invention, another exemplary embodiment of a rotary switch in accordance with the present invention comprises a resilient wire.
Also in accordance with the objects of the present invention, another exemplary embodiment of a rotary switch in accordance with the present invention comprises a resilient wire having a first end, a second end, and a middle portion, the middle portion being biased toward the contact surface on the thrust axis.
Also in accordance with the objects of the present invention, in another exemplary embodiment of a rotary switch in accordance with the present invention, the middle portion of the wiper resilient wire defines a wiper contour, the contact surface defines a contact surface contour, and the contact surface contour is complementary to the wiper contour.
Also in accordance with the objects of the present invention, in another exemplary embodiment of a rotary switch in accordance with the present invention, the middle portion of the wiper resilient wire is movable between a relatively compressed position and a relatively relaxed position on the thrust axis relative to the contact surface, the wiper resilient wire being in the relatively relaxed position when the wiper and the contact surface are in the first relative position.
Also in accordance with the objects of the present invention, in another exemplary embodiment of a rotary switch in accordance with the present invention, the housing forms a cylindrical end; the cylindrical end has an outer surface defining a circumferentially oriented circular retaining groove; the rotor forms a cylindrical shell; the shell defines a retaining tooth; and the retaining tooth is approximated to the retaining groove to affix the rotor to the housing.
Also in accordance with the objects of the present invention, another exemplary embodiment of a rotary switch in accordance with the present invention comprises a housing; a rotor approximated to the housing; an electrically conductive wiper disposed on the housing; an electrically conductive contact surface disposed on the rotor; the wiper and the contact surface being movable between a first relative position and a second relative position; an electrical circuit being closed comprising the wiper and the contact surface in series when the wiper and the contact surface are in the first relative position, the electrical circuit being opened when the wiper and the contact surface are in the second relative position; the housing defining an axis of rotation, the rotor being rotatable about the axis of rotation with respect to the housing to provide the first and second relative positions of the wiper and the contact surface; the wiper being confined at an angular position about the axis of rotation on the housing, and the contact surface being confined at an angular position about the axis of rotation on the rotor, such that, with rotation of the rotor about the axis of rotation with respect to the housing, the wiper and the contact surface are moved between the first and second relative positions; the wiper and the contact surface when in the first relative position defining a thrust axis; the wiper being supported on the housing with respect to the thrust axis, and the contact surface being supported on the rotor with respect to the thrust axis, such that the wiper and the contact surface are urged into mutual electrical contact when in the first relative position; the housing and the rotor cooperating to provide resistance to rotation of the rotor relative to the housing when the wiper and the contact surface are in the first relative position, whereby the first relative position is stabilized.
Also in accordance with the objects of the present invention, in another exemplary embodiment of a rotary switch in accordance with the present invention comprises a wherein the housing defines a position key, the rotor defines a shell, and the position key and the shell cooperate to provide resistance to rotation of the rotor relative to the housing when the wiper and the contact surface are in the first relative position.
Also in accordance with the objects of the present invention, in another exemplary embodiment of a rotary switch in accordance with the present invention, the housing forms a cylindrical end; the position key projects radially outward from the cylindrical end; the rotor forms a cylindrical shell; the rotor is approximated to the cylindrical end; and the position key contacts the shell to provide resistance to rotation of the rotor relative to the housing when the wiper and the contact surface are in the first relative position.
Also in accordance with the objects of the present invention, in another exemplary embodiment of a rotary switch in accordance with the present invention, the housing forms a cylindrical end; the cylindrical end has an outer surface defining a circumferentially oriented circular retaining groove; the rotor forms a cylindrical shell; the shell defines a retaining tooth; and the retaining tooth is approximated to the retaining groove to affix the rotor to the housing.
Also in accordance with the objects of the present invention, in another exemplary embodiment of a rotary switch in accordance with the present invention, a plurality of electrically conductive contact surfaces are disposed on the rotor; the wiper and the contact surface being movable between a plurality of relative positions; an electrical circuit being defined comprising the wiper and one of the plurality of contact surfaces in series when the wiper and the one of the plurality of contact surface are in each of the relative positions, the electrical circuit being defined as open when the wiper and the contact surface are in one of the relative positions, whereby the rotary switch is positionable to select any of a plurality of electrical functions or none of them.
It is an advantage of the present invention that the switch housing and the rotor may both be made inexpensively of a nonconducting material such as a thermoplastic or paper product. Only the ground wire, the wiper, the electrically conductive contact surfaces and other electrical elements need be made of an electrically conductive material.
It is an additional advantage of the present invention that the rotor may be equipped with two, three, or more contact surfaces, any number of which may be selectively electrically connectable to other electrical elements to provide a desired electrical function, and any number of which may be electrically isolated (or formed of an electrically nonconductive material) to provide one or more “off” switch positions.
It is an additional advantage of the present invention that specific electrical functions can be added or altered, without redesigning the rotary switch, by changing the specifications of the circuit module that is to be used in conjunction with the rotary switch.
BRIEF DESCRIPTION OF THE-DRAWINGS
For a further understanding of the objects and advantages of the present invention, reference should be had to the following detailed description, taken in conjunction with the accompanying drawing, in which like parts are given like reference numbers and wherein:
FIG. 1
is a partially cut-away side view of a rotary switch in accordance with the present invention;
FIGS. 2 AND 3
are partial side sectional views of a rotary switch in accordance with the present invention;
FIG. 4
is a partial perspective view of the housing front end for a rotary switch in accordance with the present invention;
FIG. 5
is a partial perspective view of a rotor for a rotary switch in accordance with the present invention;
FIG. 6
is a partial side sectional view of a housing front end and a switch rotor approximated thereto to form a rotary switch in accordance with the present invention;
FIG. 7
is a side perspective sectional view of a housing front end and a switch rotor approximated thereto to form a rotary switch in accordance with the present invention;
FIG. 8
is a front end perspective sectional view of a housing front end and the rotor hub portion of a switch rotor approximated thereto in a rotary switch in accordance with the present invention; AND
FIG. 9
is a rear end perspective view of a switch rotor of a rotary switch in accordance with the present invention as seen from inside the battery cell housing.
DESCRIPTION OF A PREFERRED EMBODIMENT OF THE INVENTION
The invention will now be described with reference to
FIG. 1
, which shows a partial cut-away side view of a preferred embodiment of a rotary switch in accordance with the present invention, represented generally by the reference number
30
. The rotary switch
30
is shown as being incorporated into the core of a flashlight
32
. The flashlight
32
has a cylindrical battery cell housing
34
having a housing inner side surface
36
, a housing outer side surface
38
, a housing front end
40
, and a housing rear end
42
.
A cap
44
is securably disposed on the housing rear end
42
. The battery cell housing
34
encloses two storage batteries
46
which are oriented with positive button battery terminals
48
oriented toward the housing front end
40
and a negative button battery terminals
50
oriented toward the housing rear end
42
. The cap
44
includes an electrically conductive cap spring
52
which is biased to be in contact with the negative button battery terminal
50
. A ground wire
76
is disposed in the battery cell housing
34
and has a ground wire rear end
78
electrically connected to the cap spring
52
and a ground wire front end
80
which extends into the housing front end
40
.
A generally hollow switch rotor
82
is disposed on the housing front end
40
. The switch rotor
82
has a cylindrical rotor shell
86
which defines four circumferentially spaced apart, rearwardly projecting rotor side portions
92
which fit over the housing front end
40
. The switch rotor
82
has a rotor front end
84
in which is mounted a miniature light bulb
102
. Four positioning prongs
60
project forward from the housing front end
40
. Each positioning prong
60
defines a position key
64
. In
FIG. 1
, the position keys
64
are shown which projecting radially outward between adjacent rotor side portions
92
.
FIGS. 2 and 3
are partial side views of the battery cell housing
34
detailing the housing front end
40
. Proximate the housing front end
40
, the housing outer side surface
38
defines a circumferentially oriented circular retaining groove
54
. The housing front end
40
defines a circular housing front opening
56
. The housing front end
40
is longitudinally incised to define four circumferentially spaced-apart housing side portions
58
and four circumferentially spaced-apart positioning prongs
60
. Each positioning prong
60
has a prong distal end
62
which forms a position key
64
. Each position key
64
projects radially outward beyond the radius defined by the housing outer side surface
38
at the housing front end
40
. Proximate the housing front end
40
, the housing inner side surface
36
defines a circumferentially oriented arcuate ground wiper stabilizing groove
66
. A ground wire channel
75
is inscribed in the housing inner side surface
66
.
FIG. 4
is a partial perspective view of the battery cell housing
34
detailing the housing front end
40
. The retaining groove
54
, housing front opening
56
, housing side portions
58
, positioning prongs
60
, prong distal ends
62
, and position keys
64
are shown.
FIG. 5
is a partial perspective view showing a generally hollow switch rotor
82
having a rotor front end
84
and a cylindrical rotor shell
86
which extends rearward to form a rotor rear end
88
and to define a rotor inner side surface
90
. The rotor rear end
88
is longitudinally incised to form four circumferentially spaced-apart rotor side portions
92
. Proximate the rotor rear end
88
, each rotor side portion
92
forms a radially inwardly projecting retaining tooth
94
. Each rotor side portion
92
is formed of an elastic material and is radially outwardly deformable in response to applied force.
The rotor front end
84
defines a rotor front surface
96
, a central portion of which forms a light bulb socket
98
comprising a pair of electrically conductive channels
100
for accommodating a miniature light bulb. The periphery
107
of the rotor front end
84
forms a radially outwardly projecting engagement finger
109
, the purpose of which is to provide spline-like rotational coupling to an inwardly-grooved exterior sleeve (not shown) which may be mounted radially outwardly of the switch rotor
82
.
FIG. 6
is a partial side sectional view of the switch
30
showing the rotor
82
mounted on the housing front end
40
. Two electrically conductive channels
100
are defined in the rotor front end
84
. A miniature bulb
102
has a first bulb lead
104
and a second bulb lead
105
. The bulb leads
104
and
105
are respectively inserted in the channels
100
.
The rotor has an inner side surface
90
which has an inside diameter at least as great as the outside diameter of the housing outer surface
38
of the housing front end
40
. When the switch rotor
82
is mounted on the housing front end
40
, the, retaining tooth
94
formed on each elastic rotor side portion
92
interferes with the housing outer surface and the rotor side portion is deformed radially outward. When the rotor switch is urged far enough rearward onto the housing front end
40
, each retaining tooth
94
fits into the circumferentially oriented circular retaining groove
54
in the housing outer surface, whereupon each elastic rotor side portion
92
is biased radially inward such that the retaining tooth
94
is seated in the retaining groove
54
. The switch rotor
82
will then remain in a longitudinally stable position on the housing front end
40
until it is forcibly removed.
FIG. 7
is a side sectional perspective view showing the housing front end
40
including the retaining groove
54
, the positioning prongs
60
and the position keys
64
, and the ground wiper stabilizing groove
66
, in which is disposed a deformable, electrically conductive ground wiper
68
. Also shown are the rotor
82
including rotor side portions
92
with retaining teeth
94
, and rotor front end
84
with rotor front surface
86
. The rotor front end
84
forms a centrally located, rearwardly projecting rotor hub
106
having a rotor hub rear surface
108
and a cylindrical rotor hub side surface
110
.
FIGS. 6 and 7
also show a circuit housing
99
located within the rotor hub
106
and proximate the rotor hub rear surface
108
. The circuit housing
99
contains one or more electrical circuits for connection in series between the second bulb lead
105
and the positive button terminal
48
of the storage battery
46
.
FIG. 8
is a front end sectional perspective view of the rotor hub
106
positioned within the housing front end
40
. With reference to
FIGS. 7 and 8
, the arcuate, horizontally oriented ground wiper stabilizing groove
66
is shown. The ground wiper
68
has a ground wiper first end
70
, a ground wiper second end
72
, and a radially inwardly deviating ground wiper middle portion
74
. The ground wiper
68
is oriented generally horizontally within the ground wiper stabilizing groove
66
that is formed in the housing inner side surface
36
in the housing front end
40
. The ground wiper first end
70
and the ground wiper second end
72
are lodged in the ground wiper stabilizing groove
66
. The ground wiper middle portion
74
is biased to a position radially inward of the ground wiper first end
70
and the ground wiper second end
72
and is radially outwardly deformable in response to a force applied to the wiper middle portion
74
. The ground wiper first end
70
is electrically connected to the ground wire front end
80
.
The rotor hub side surface
110
forms first, second, third and fourth cylindrical concave rotor ground contact surfaces
112
,
114
,
116
, and
118
, which are circumferentially spaced-apart at ninety degrees from one another. First rotor ground contact surface
112
is electrically isolated from the first bulb lead
104
. Second rotor ground contact surface
114
is electrically connected to the first bulb lead
104
through a conductive electrical element (not shown). Third rotor ground contact surface
116
is electrically connected to the first bulb lead
104
through an intermittently conductive electrical element (not shown). Fourth rotor ground contact surface
118
is electrically connected to the first bulb lead
104
by a resistive electrical element (not shown).
The rotor hub side surface
110
also defines a horizontally oriented circular guiding groove
120
. The guiding groove
120
is located on the rotor hub side surface
110
such that, when the rotor
82
is mounted on the housing front end
40
, the guiding groove
120
is adjacent the ground wiper stabilizing groove
66
that is formed in the housing inner surface
36
. The guiding groove
120
and the ground wiper stabilizing groove
66
cooperate to confine the ground wiper
68
longitudinally while allowing it to move radially. The arc of the ground wiper retaining groove
66
extends circumferentially only far enough to accommodate the ground wiper first end
70
and the ground wiper second end
72
, thereby circumferentially (rotationally) stabilizing the ground wiper
68
relative to the housing
34
.
FIG. 9
is a rear end perspective view of the rotor
82
as it would be seen from within the battery cell housing
34
.
FIG. 9
shows the rotor side portions
92
, the engagement tooth
109
, the retaining teeth
94
, and the rotor hub
106
with the guiding groove
120
. As shown in
FIG. 9
, the circuit housing
99
is defined as a rectangular cavity in the rotor hub rear surface
108
. Two conductors
122
and
124
are disposed in the hub rear surface
108
at a location facilitating their electrical contact with one or more electrical leads of a resistor, flasher, or solid state circuit module (not shown) which may be inserted in the circuit housing
99
. Such a circuit module would additionally have an electrical battery lead located thereon such that, when the circuit module is inserted in the circuit housing and a battery cell
46
is correctly inserted in the battery cell housing
34
, an circuit is established between the positive button battery terminal
48
and at least one of the two conductors
122
and
124
.
With reference again to
FIGS. 6 and 7
, it is seen that because the retaining groove
54
in the housing outer side surface
38
is continuous, the retaining teeth
94
of the rotor side portions
92
are relatively free to slide circumferentially (rotationally) in the retaining groove
54
. However, it will be remembered that a position key
64
projects radially outward from the prong distal end
62
of each positioning prong
60
of the battery cell housing
34
. Therefore, when the switch rotor
82
is mounted on the housing front end
40
and a rotor side portion
92
is positioned directly radially outward of each position key
64
, each position key
64
applies a radially outward force to the corresponding rotor side portion
92
. As a result, the position keys
64
are urged radially inward and the positioning prongs
60
are elastically deformed. When the switch rotor
82
is rotationally positioned so that each position key
64
is disposed at an angular position between adjacent rotor side portions
86
, each position key
64
projects radially outward into the gap defined between adjacent rotor side portions
86
, allowing the positioning prongs
60
to rebound. In this way, the rotor side portions
86
cooperate with the position keys
64
to stabilize the switch rotor
82
in any of four rotational positions relative to the battery cell housing
34
.
The first, second, third and fourth rotor ground contact surfaces
112
,
114
,
116
and
118
are rotationally positioned relative to the rotor side portions
86
such that, when the switch rotor
82
is stabilized in one of the four rotational positions relative to the battery cell housing
34
, one of the four rotor ground contact surfaces
112
,
114
,
116
and
118
is positioned in contact with the ground wiper middle portion
74
. Thus, when the switch rotor
82
is rotated from one of these four positions to another relative to the battery cell housing
34
, the nature of the electrical connection between the battery negative button terminal and the first bulb lead
104
is altered.
The effect of this altered connection will depend on the nature of the electrical circuit that is contained in the circuit housing
99
. The rotary switch
30
in accordance with the present invention is designed to be used in conjunction with a variety of such circuits. In the preferred embodiment that has been described with reference to
FIG. 8
, first rotor ground contact surface
112
is electrically isolated from the first bulb lead
104
and thus, when the wiper middle portion
74
is positioned on the first rotor ground contact surface
112
, no circuit is completed between the ground wire
76
and the bulb. This switch position therefore selectis an “off” function. When the rotor
2
is turned relative to the housing
34
and the wiper middle portion
74
is thus rotated onto the second and subsequent rotor ground contact surfaces,
114
,
116
, etc., various other functions are selected as various of the circuits that are provided by the circuit module (not shown) are electrically connected between the first bulb lead
104
and the respective rotor ground contact surfaces
114
,
116
, etc. As a practical matter, an additional electrical conductor (not shown) is disposed on or in the rotor hub portion
106
to connect each of the ground contact surfaces
114
,
116
, etc. to the circuit module that is to be placed in the circuit housing
99
. Each such conductor has a terminal located on a surface of the circuit housing
99
. The circuit module must be insertable within the circuit housing
99
and should, ideally, achieve an interference fit or other economical and reliable form of attachment therewith, and must have an electrical lead so located thereon as to contact each of the conductor terminals on the surface of the circuit housing
99
.
The battery cell housing and the rotor may be formed of nonconducting materials such as plastics, paper products, textiles, wood, glass, ceramic or the like. The battery cells may be, for example, size “C” or size “A.”
In another exemplary embodiment of a rotary switch in accordance with the present invention, the rotor hub portion
106
defines a plurality of up to twenty (20) circumferentially spaced apart rotor ground contact surfaces and the rotor includes up to 20 circumferentially spaced-apart rotor side portions. Similarly, the housing front end
40
defines a plurality of positioning prongs for engagement and cooperation with the rotor in a manner analogous to that already described herein. It will be appreciated that if M is the number of positioning prongs and N is the number of rotor side portions, the adoption of a variety of different angular spacing intervals for the rotor side portions, the positioning prongs, or both can under some circumstances result in a number of positions greater than M or N.
In another exemplary embodiment, the number of rotor ground contacts exceeds the number of positions that is stabilized by the cooperation of the rotor side portions and the positioning prongs. As a result, relatively smooth rotation is provided between several electrically distinct switch positions.
In another exemplary embodiment, the ground wiper contacts and the ground wiper are formed large enough and strong enough to stabilize the rotor in one or more rotational positions relative to the housing as a result of the deformation of the ground wiper.
While the foregoing detailed description has described several embodiments of a rotary switch in accordance with the present invention, it is to be understood that the above description is illustrative only and not limiting of the disclosed invention. It will be appreciated that the embodiments discussed above and the virtually infinite embodiments that are not mentioned could easily be within the scope and spirit of the present invention. Thus, the present invention is to be limited only by the claims as set forth below.
Claims
- 1. A rotary switch, comprising:a housing; a rotor approximated to said housing; an electrically conductive wiper disposed on said housing; an electrically conductive contact surface disposed on said rotor; said wiper and said contact surface being movable between a first relative position and a second relative position; an electrical circuit being closed comprising said wiper and said contact surface in series when said wiper and said contact surface are in said first relative position, said electrical circuit being opened when said wiper and said contact surface are in said second relative position; said housing defining an axis of rotation, said rotor being rotatable about said axis of rotation with respect to said housing to provide said first and second relative positions of said wiper and said contact surface; said wiper being confined at an angular position about said axis of rotation on said housing, and said contact surface being confined at an angular position about said axis of rotation on said rotor, such that, with rotation of said rotor about said axis of rotation with respect to said housing, said wiper and said contact surface are moved between said first and second relative positions; said wiper and said contact surface when in said first relative position defining a thrust axis; said wiper being supported on said housing with respect to said thrust axis, and said contact surface being supported on said rotor with respect to said thrust axis, such that said wiper and said contact surface are urged into mutual electrical contact when in said first relative position; said housing and said rotor cooperating to provide resistance to rotation of the rotor relative to the housing when said wiper and said contact surface are in said first relative position, whereby said first relative position is stabilized; said housing defining a position key, said rotor defining a shell, said position key and said shell cooperating to provide resistance to rotation of the rotor relative to the housing when said wiper and said contact surface are in said first relative position.
- 2. A rotary switch as set forth in claim 1, wherein:said housing forms a cylindrical end; said position key projects radially outward from said cylindrical end; said rotor forms a cylindrical shell; said rotor is approximated to said cylindrical end; and said position key contacts said shell to provide resistance to rotation of the rotor relative to the housing when said wiper and said contact surface are in said first relative position.
- 3. A rotary switch as set forth in claim 2, wherein:said cylindrical end of said housing has an outer surface defining a circumferentially oriented circular retaining groove; said cylindrical shell of said rotor defines a retaining tooth; and said retaining tooth is approximated to said retaining groove to affix said rotor to said housing.
US Referenced Citations (10)