U.S. patent number RE30,094 [Application Number 05/846,733] was granted by the patent office on 1979-09-11 for optoelectronic switch.
This patent grant is currently assigned to Tektronix, Inc.. Invention is credited to Carlos L. Beeck.
United States Patent |
RE30,094 |
Beeck |
September 11, 1979 |
Optoelectronic switch
Abstract
A light actuated switch apparatus is described in which no
movable switch contacts are employed. The switch uses a light
source and shutter to activate an array of light sensitive devices
to generate a binary code that provides the switching function. One
embodiment of the switch apparatus is employed inside a control
knob providing a binary code generated by shutter action of a light
source on an array of photo-transistors. Another embodiment
.[.employes.]. .Iadd.employs .Iaddend.the above control knob
including switch apparatus as well as a second knob and printed
board to form a dual switch apparatus. As no switch contacts are
employed there is considerable reduction in electrical components.
Additionally, this also greatly reduces the space required for
mounting the switch, is readily serviceable or replaceable as no
parts are located within an instrument, and is less expensive as no
contacts eliminate any wear and potential problems associated with
movable through stationary contacts.
Inventors: |
Beeck; Carlos L. (Aloha,
OR) |
Assignee: |
Tektronix, Inc. (Beaverton,
OR)
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Family
ID: |
27050808 |
Appl.
No.: |
05/846,733 |
Filed: |
October 31, 1977 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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Reissue of: |
492625 |
Jul 29, 1974 |
03946225 |
Mar 23, 1976 |
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Current U.S.
Class: |
250/229;
250/214PR; 341/13 |
Current CPC
Class: |
H03K
17/968 (20130101) |
Current International
Class: |
H03K
17/968 (20060101); H03K 17/94 (20060101); G01D
005/34 () |
Field of
Search: |
;250/211K,237R,237G,229,568,570,239 ;235/61.11E ;340/365P |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
Primary Examiner: Nelms; David C.
Attorney, Agent or Firm: Winkelman; John D.
Claims
The invention is claimed in accordance with the following: .[.1. An
optoelectronic switch, comprising:
a movable housing member,
stationary radiation source means disposed inside said movable
housing member, said stationary radiation source means for
providing electromagnetic radiation;
movable masking means operably disposed in said movable housing
member, said masking means for selectively masking said
electromagnetic radiation to provide a coded electromagnetic
radiation; and
stationary radiation sensitive means disposed inside said movable
housing member, said stationary radiation sensitive means for
collecting said coded electromagnetic radiation to provide an
output electrical signal proportional to said coded electromagnetic
radiation..]. .[.2. The switch according to claim 1 further
comprising:
connecting means disposed within said movable housing member, said
connecting means for connecting said movable housing means and said
movable masking means together..]. .[.3. The switch according to
claim 2 wherein said movable housing member defines a knob
member..]. .[.4. The switch according to claim 1 wherein said
stationary radiation source means defines a light member..]. .[.5.
The stationary radiation source member according to claim 4 wherein
said light member defines a light emitting diode..]. .[.6. The
switch according to claim 1 wherein said movable masking means
defines a shutter means..]. .[.7. The movable masking means
according to claim 6 wherein said shutter means defines a coded
shutter member coded in a preselected pattern..]. .[.8. The switch
according to claim 1 wherein said stationary radiation sensitive
means defines a light sensitive member..]. .[.9. The switch
according to claim 8 wherein said light sensitive member defines a
phototransistor..]. .[.10. The switch according to claim 8 wherein
said light sensitive member defines a charge
coupled device..]. 11. An optoelectronic switch, comprising:
a first movable housing member;
a second movable housing member operatively disposed within said
first movable housing member;
stationary radiation source means disposed within said second
movable housing member, said stationary radiation source means for
providing electromagnetic radiation;
movable masking means operatively disposed in said second movable
housing member, said movable masking means for selectively masking
said electromagnetic radiation to provide a coded electromagnetic
radiation;
stationary radiation .[.sensative.]. .Iadd.sensitive .Iaddend.means
disposed inside said second movable housing member, said stationary
radiation sensitive means for collecting said coded electromagnetic
radiation to provide an electrical signal proportional to said
coded electromagnetic radiation; and
means operatively disposed inside said first housing member, said
means for selectively receiving said .[.electricl.].
.Iadd.electrical
.Iaddend.signal to provide a selectable electrical signal. 12. The
switch according to claim 11 wherein said first and said second
movable housing
members move independently from one another. 13. The switch
according to claim 11 wherein said means operatively disposed
inside said first movable housing member defines a circuit board
means including selectable connection members. .Iadd. 14. An
optoelectronic switch, comprising
a rotatable housing,
a masking member mounted within and coupled to said housing for
rotation therewith, said member including a plurality of light
transmissive windows,
stationary light sensitive means disposed within said housing
facing one side of said masking member for detecting incident light
and generating an electrical signal proportional thereto, and
stationary light source means disposed within said housing facing
the opposite side of said masking member for directing light toward
said light sensitive means,
1ight from said source means passing through certain of said
windows at different rotational positions of said housing to
illuminate said light sensitive means and thereby produce
electrical output signals at such positions. .Iaddend..Iadd. 15.
The switch of claim 14, further including detent means within said
housing for indexing said masking member at different rotational
positions. .Iaddend..Iadd. 16. The switch of claim 14, wherein said
masking member comprises a disc mounted for axial rotation, said
windows being disposed in a selected pattern in the disc to provide
different electrical output signals at different rotational
positions. .Iaddend..Iadd. 17. The switch of claim 14, wherein said
light sensitive means comprises a plurality of photodetectors and
said light source means comprises a like plurality of light
emitting devices, each directing light toward a different one of
said photodetectors, different individual ones and groups of said
photodetectors being illuminated by light passing through said
windows at different rotational positions of the housing to
generate different, coded electrical signals at such positions.
.Iaddend.
Description
BACKGROUND OF THE INVENTION
Previously, several switches have been made which relate in general
to electrical circuits whether singular or in a dual assembly in
which two different switches are operated independently by means of
a common shaft or which can be operated together. In these
switches, .[.their.]. .Iadd.there .Iaddend.exists a stationary
stator plate and a movable rotor plate properly positioned to
change the electrical connections of the switch contacts by
rotational or longitudinal movements of a knob device secured to
the common shaft. Thus, a disadvantage arises due to wear of moving
parts, namely between the stationary stator plate and the movable
rotor plate as the knob device is moved. Another disadvantage
inherent to these switches is that many require elaborate
provisions be made if they are to intrude into an instrument and
occupy significant space. Another disadvantage is that three
dimensional cabling is required. Typical of the above described
switches are the switches fully described in U.S. Pat. Nos.
3,074,011; 3,181,086; 3,187,118 and 3,207,861 all of which are
assigned to the assignee of the present invention. Another type
switch apparatus employs its movable and fixed switch contacts on a
printed circuit board providing the electrical circuit to which the
switch contacts are connected as fully described in U.S. Pat. No.
3,562,464 by Charles Howard Vollum et al and assigned to the
assignee of the present invention. Such apparatus, however,
requires significant space, and is subject to wear.
The application of encoding-decoding by light source, mask and
photoreceptors is also well known in the art. For example, U.S.
Pat. No. 3,491,244 by V. E. Stewart, Jr. describes an encoder for
use in an automatic remote meter reading system which includes a
plurality of photo cells disposed between a pair of coded discs and
are arranged to be selectively energized from their opposite sides
by individual illuminating means associated with each disc. Typical
of the encoders and decoders employing coded discs having light
openings in a radial array representative of the binary code, such
that the position to which the disc is rotated relative to a fixed
light source provides an indication in binary form are taught by
U.S. Pat. Nos. 3,489,907; 3,740,721; 3,399,297; 3,237,012; and
3,512,006. Thus a disadvantage is that such use of
encoding-decoding by light source, mask and photoreceptors are not
applied to a switch.
SUMMARY OF INVENTION
The switch apparatus of the present invention relates generally to
electrical switches and in particular to optoelectronic switches in
which light from a light source is directed by means of a baffle
and is interrupted by a shutter having a preselected pattern to
pass the light in the form of a binary code onto an array of photo
sensitive devices that uses the binary coded light to thus generate
a binary code used to drive associated circuitry such as, for
example, TTL logic circuits. The switch apparatus is built inside a
control knob and uses no movable contacts.
It is therefore an object of the present invention to provide a new
and improved electrical switch having no movable contacts.
It is another object of the present invention to provide a switch
apparatus within a knob.
It is yet another object of the present invention to provide an
optoelectronic switch requiring a minimum of space.
It is still another object of the present invention to provide
switch apparatus of long, useful lifetime having no movable
contacts.
It is still yet another object of the present invention to provide
a plurality of switches within a plurality of control knobs.
The subject matter of the present invention is particularly pointed
out and distinctly claimed in the following description. The
invention, however, both to organization and method of operation
together with further advantages and objects thereof may best be
understood by reference to the following description taken in
connection with the accompanying drawings. It is to be understood,
however, that these embodiments are not intended to be exhausting
nor limiting of the invention but are for the purposes of
illustration in order that others skilled in the art may fully
understand the invention and principles thereof and the manner of
applying it in particular use so that they may modify it in various
forms, each as may best be suited to the conditions of the
particular use.
BRIEF DESCRIPTION OF THE DRAWINGS
In the drawings:
FIG. 1 is a partial side elevation of a typical electrical switch
in accordance with the prior art;
FIG. 2 is a partial cross-section view of an apparatus using a
plurality of photo cells, light sources and coded discs in
accordance with prior art;
FIGS. 3A-3E are an exploded isometric drawing of the optoelectronic
switch according to the present invention;
FIG. 4 is an isometric view of the optoelectronic switch in
accordance with FIG. 3 mounted on, say, the front-panel portion of
an instrument; and
FIG. 5 is an isometric view of a dual optoelectronic switch
according to the present invention.
DETAILED DESCRIPTION OF INVENTION
Referring now to the drawings, and in particular to FIG. 1, there
is shown a side elevation of an electrical switch assembly in
accordance with the prior art, namely U.S. Pat. No. 3,187,118
previously mentioned. The switch includes knob devices 1 and 2,
connected to a first switch shaft 3 and a second switch shaft 4.
The first shaft 3 is such that second shaft 4 can rotate inside the
first shaft. Each of these shafts actuate different switch devices
and such switch devices may be of any type where electrical
connections can be controlled by the rotation of a switch shaft. In
the example shown, a first switch device 5 is actuated by the first
switch shaft 3 and the second switch device 6 is actuated by the
second shaft 4. The two shafts 3, 4 are supported in an L-shaped
support bracket 7 by a sleeve member 8 in which the shaft 3 is
journaled for rotation and also held against endwise movement with
respect to the sleeve member. The sleeve member 8 has a
screw-threaded end extending through the bracket 7. A nut 9 on such
end secures the sleeve member in position in the support bracket.
The support bracket 7 is mounted in an instrument chassis by means
of a pair of nut, bolt and lock washer assemblies 10 so that the
switch shafts extend through an opening 11 in the control panel 12
of the instrument and are connected to the knob devices 1, 2 on the
front of such panel.
Shown in FIG. 2 is a cross-sectional view of an apparatus utilizing
a coded disc having light openings, in a radial array disposed
between a light source and a plurality of photo cells in accordance
with the prior art, namely U.S. Pat. No. 3,399,297 previously
mentioned. A central shaft 20 has its outer end supported in a
bearing block 22. Secured to the shaft 20 is a nylon gear 24 which
is secured to the shaft by means of a set screw 26. The gear 24, in
turn, meshes with gear 28 which is slideably received on a main
drive shaft 30, the main drive shaft 30 being driven by means of
say, a control knob, etc. Secured to its hub portion, the gear 24
carries a coded disc 31. Radially spaced along one side of the
coded disc 31 are a plurality of light sources or lamps A1-A5.
These lamps are such as to direct beams of light against a
photocell element 32 positioned on the side of the disc 31 directly
opposite the lamps A1-A5. The photocell will conduct an electrical
current in accordance with the amount of light received from the
lamps A1-A5 via the coded disc 31, such current being in a binary
code and can be used to drive associated circuitry.
As can be discerned from the above described prior art switches and
optoelectric devices, a combination optoelectric switch could be
made by those skilled in the art. However, the disadvantages of
such a combination i.e., space requirements great and wear of gear
elements, etc., have not been overcome. Thus, in order to satisfy a
concept of instrumental design to provide a switch which overcomes
the disadvantages of the prior art, there is shown in FIG. 3 an
isometric exploded drawing of the optoelectronic switch according
to the present invention; FIG. 4 is an isometric drawing of the
switch shown in FIG. 3 mounted on, say, the front-panel portion of
an oscilloscope. Briefly considering the drawings shown in FIGS. 3
and 4, the entire switch assembly is mounted within a knob shell 50
and attached to the panel portion 52 of an instrument via securing
members 51 such as screws, etc., received by connection members 54.
A plurality of stationary contact members 53 are provided for
inputing and outputing the electric switching current used to drive
or to be received by associated circuitry.
Referring specifically to FIG. 3A, for disposal into knob shell 50
are the components of the optelectronic switch including a shaft
assembly 55, detent follower and stop assembly 65, spring member
73, light holder assembly 75, baffle member 90, coded disc member
95, spring and spacer member 100, light collector assembly 125 and
a retaining spring member 140. Thus, the length of the knob shell
50 is determined by the components required. In the particular
embodiment shown, it has been found that a length of 3/4 inch
provides a knob shell compatable with other traditional knob
shells. Knob shell 50 is preferably formed as a single unit from a
suitable plastic such as glass filled polycarbonate. FIG. 3B shows
that the knob shell 50 includes a plurality of recessed areas 200,
201, 202 and 203. A guide portion 204 protrudes towards the knob
center in the recess area 201 and will be discussed shortly. A
plurality of guide stubs 205 protrudes upwards in the recess area
202, such stubs will also be described later in this description.
The recess area 203 accepts the already mentioned retaining spring
member 140. The recess area 200 is provided for receiving the shaft
assembly 55, such shaft assembly having a ridge area 57 and an
elongated area 58 extending orthogonally from the ridge area 57.
Disposed into the elongated area 58 and traversing therealong are a
plurality of grooves 59 and 60. As will be described later, a dual
switch apparatus is provided which uses a similar, but longer
shaft. Alternatively, however, the area of the elongated area 58 of
shaft member 55 can be determined so that such area is suitable to
allow a coaxial shaft inside it. Thus, ridge area 57 and the recess
area 200 of knob shell 50 are dimensionally established. Disposed
into the groove 60 is a contact blade 61 which forms one of a
plurality of stationary contacts 53 (see FIG. 4) for the
optoelectronic switch. Such blade is a conductive member,
preferably metal, molded to an insulator member 62, which is
preferably plastic, then attached to the shaft in the groove 60.
Electrically, the contact blade 61 will not be at the same
potential as the shaft due to the insulative characteristics of the
plastic insulator member 62. As contact blade 61 forms a stationary
contact, it is indeed obvious that when ridge area 57 is disposed
into the recess area 200 of knob shell 50, no mechanical rigidity
will exist therebetween. Disposed into the second groove 59 is a
machine key 63, such key extending above the surface of the
elongated area 58 and traversing therealong for providing a guide
and lock assembly for the switch components. The use of a machine
key is quite well known to those in the field and therefore will
not be described in detail.
A detent follower and stop assembly 65 is next provided and is
shown in detail in FIG. 3C. Included are a housing member 66,
detent roller member 67, detent gear member 68 and a detent locking
spring member 69. Housing member 66 is preferably a single unit
formed from thermoplastic such as nylon, and includes a hub portion
70, a plurality of spring member supports 71 alternately spaced
around the periphery edges of the member and a spring slot 72. An
alignment member of semicircle shape extends across the outer
surface of the member and includes a groove 74. The inner portion
of the housing member, shown in FIG. 3D, includes a second hub
portion 81 and a wedge shaped gear stop member 82. An aperture 77
is provided in the housing member and extends from the inner
surface to the outer surface, such aperture for accepting the
detent roller member 67. Detent gear member 68 is provided with a
plurality of protuberances 79 for contacting the wedge gear stop
member 82 and a groove 80 for accepting the machine key way
discussed; such member preferably a single unit molded from an
acetal-plastic such as DELRIN. The outer periphery of the gear is
provided with a plurality of spaced indentations to define gear
teeth. Detent lacking spring member 69 is a circular shaped spring
member having one of its ends turned in a direction for disposal
into the slot 72. Such spring will positively secure detent roller
member 67 into one of the gear teeth.
The entire detent follower and stop assembly 65 is then placed over
the elongated area 58 of the shaft assembly 55 and made to contact
the ridge area 57 via hub portion 70. As the shaft assembly 55 is
disposed into the recess area 200 of knob shell 50, the guide
portion 204 engages the groove 74. As can now be discerned, the
detent follower assembly 65 will advance with rotation of knob
shell 50 whereas shaft assembly 55 remains stationary relative
thereto. A next conventional spring member 73 of circular shape
insures gear member 68 remains fixed within the housing member
66.
Light holder assembly 75 including a light source 76 is next
carried by shaft assembly 55 and is held into position by the
machine key 63 via the groove 77 provided in the assembly. As is
well known from prior art, the light source must be accurately
positioned in relation to the light collector (to be described
later). In the prevent invention, the light source is provided by
light emitting didoes (LED's) installed on a lead frame and
encapsulated by transfer molding in transparent epoxy with
integrally molded focusing lenses. The LED's thus packaged are
secured onto a carrier base 85 via a clip means 78 and soldered in
place permanently, one lead onto the metal circular shaped carrier
base 85 and the other lead to contact blade 61. A plurality of tabs
87 provide electrical contact between carrier base 85 and the
elongated area 58 of shaft assembly 55. Although the preferred
embodiment uses an LED array for providing electromagnetic
radiation, another arrangement can be a lamp and colluminating
mirror, etc., all of which are well known. A next unit carried by
and keyed to shaft assembly 55 is a light source baffle member 90.
Baffle 90 is preferably formed as a single unit whose composition
is similar to the housing member 66 and includes an opening 91 of
desired shape therethrough so that when properly keyed on the shaft
assembly, will funnel the electromagnetic radiation through the
aperture from the light source means and block such electromagnetic
radiation otherwise.
A binary coded shutter disc member 95 has therein chemically milled
holes 96 in a preselected pattern to selectively pass the funneled
electromagnetic radiation via baffle 90. Shutter disc member 95
therefore can be considered as a means to selectively damp, or
mask, the electromagnetic radiation in accordance with a
preselected pattern required for the desired switching. Around the
periphery such disc are a plurality of alignment means 97 which
engage with guide stubs 205 located in knob shell 50. Thus, the
binary coded shutter disc member 95 also rotates with knob shell
50. It should be noted that the disc is preferably a metal which is
processed after the chemical milling of the holes to provide a
black oxide coating for light purposes, but that such preferable
structure is not intended to be limiting and that any structure to
provide the damping required would be possible.
Next provided within the switch apparatus is a spacer spring member
100 which holds shutter disc 95 in engagement with the guide stubs
205 located in knob shell 50. In addition such spacer spring
provides electrical isolation between such shutter disc and an
electromagnetic radiation collector, or detector or sensitive,
means which will be discussed shortly. In order to .[.accomodate.].
.Iadd.accommodate .Iaddend.both of the aforementioned
.[.criterion.]. .Iadd.criteria.Iaddend., spacer spring member 100
is preferably a chemically milled "MYLAR" polyester and shown in
detail in FIG. 3E. Two parallel support members 101 and 102 are
connected together via a plurality of V-shaped truss members 103.
Each of the parallel supports has one end which is truncated
inwardly towards each other a minute amount, then again parallel.
The truncated end portion provides the spacer-spring member with a
connecting means. As shown in FIG. 3A, such spring is circular in
shape and provided as such by weaving the connecting means first
between two of the plurality of V-shaped truss members, then over
one, and back between any adjacent two. Thus, connecting requires
that the truncated end portion have a width slightly less than the
width of the V-shaped truss members. It has been determined that
the V-shaped truss members provide a spring whose stress-strain
relationship follows a linear path and has good spring-back
characteristics as required. It is to be understood however, that
the spring as shown is one of many forms and is the preferred form.
For instance, the V-shaped truss members can take various shapes
and the truncated end portion can traverse outwardly, etc. The
spring can be formed, a plurality at a time, very simply and
inexpensively. Additionally, the length of such member can vary
depending upon the design characteristics required.
A next portion of the switch apparatus which is keyed to and guided
by shaft assembly 55 is the light collector assembly 125 which
includes a radiation collector, or detector or sensitive, means 126
mounted thereon. A plurality of openings 127 through a metal disc
portion 128 enable contact means 130 (stationary contact means 53
shown in FIG. 4), which are a portion of the radiation collector,
or detector or sensitive means 126, to be received through an
insulator and support member 129. A plurality of connection members
54 are provided for mounting the entire switch assembly onto an
instrument panel or the like as previously shown and described. The
radiation collector, or detector or sensitive, means 126 collects
the masked electromagnetic radiation and provides an output
proportional to such masked radiation. In the present invention,
such radiation collector, or detector or sensitive, means 125
.[.is.]. is an array of 5 phototransistor chips mounted on a lead
frame, wired in parallel and encapsulated by transfer molding in
transparent epoxy with integrally molded focusing lenses as well as
mounting stubs in a manner resembling a dual-in-line DIP package
suitable for .[. pluging.]. .Iadd.plugging .Iaddend.into an etched
circuit board, soldering or other conventional connection means.
Other types of collector means can be used which are well known in
the art such as, for example, charge coupled devices (CCD's). The
requirement for such substitution radiation collector, or detector
or sensitive means requires that an output .[.porportional.].
.Iadd.proportional .Iaddend.to the masked electromagnetic radiation
be produced. The entire switch apparatus is completed when a
conventional retaining spring member 140 is disposed into the
recessed area 203 of knob shell 50.
In the preferred embodiment of the above described switch
apparatus, the knob switch is made with five elements in the
optoelectronic array, thus is capable of 25 or 32 coded positions;
a switch having 32 positions would have 111/4.degree. per step. A
switch having, say, 18 positions or 20.degree. per step would, of
course, have the detent steps more defined relative to the 32
position switch. The desired number of switch positions are
determined by the number of teeth provided on the detent gear
member 68 and the traverse of the switch is determined by the stop
protuberancies 79.
Shown in FIG. 5 is an isometric view of a dual optoelectronic
switch according to the present invention. Such switch apparatus
includes the previously mentioned knob shell 50, shaft assembly
55', detent follower and stop assembly 65, spring member 73, light
holder assembly 75, baffle member 90, coded disc 95, spring and
spacer 100, light collector assembly 125 and the retaining spring
140. In addition, a second knob shell 50', indicator panel 145, a
second detent follower and stop assembly 150, circuit board member
160, insulator 165, and additional mounting member 170, and a
second retaining spring member 180. A minor difference exists
however, between the shaft assembly 55 and shaft assembly 55' of
FIG. 5, the latter having an elongated area of greater length to
accommodate the extra components of the dual switch. As previously
mentioned, another alternative would be a coaxially mounted shaft
within the elongated area to accommodate the extra components of
the dual switch. Knob shell 50' includes a recess area into which a
retaining spring 180 is disposed and as such, must be of sufficient
length and area so that knob shell 50 can be rotated when disposed
therein as in any type dual switch. Indicator panel 145 when
secured by, say, contact cement or other conventional securing
means to the second detent and stop assembly 150 provides an
indication as to the switch position defined by rotation of inner
knob shell 50. Detent follower and stop assembly 150 consists of a
housing member 151, a spring member 152, a roller member 153, a
detent wheel member 154 and a contact member 155. Detent wheel
member 154 is provided with a plurality of holes 157 which have one
end beveled (not shown), such holes for receiving the connection
members 54 (see FIG. 3A) on the light collector assembly 125. A
plurality of securing means such as the screw 158 connects the
units together, such a screw being disposed into the beveled end
for obvious reasons. In addition, the detent wheel member includes
gear teeth members 156 into which the detent roller 153 is engaged.
As the assembly differs only slightly from that already described
no further description will be given. A switch contact member 155
is carried by the housing member 151 for contacting circuit board
conductive areas or a circuit board member to be next discussed; as
the contact is well known it will not be discussed in detail. The
remainder of the detent and stop assembly 150 is similar to the
detent follower and stop assembly 65 and as such will not be
discussed.
A circuit board member 160 is next carried by the shaft assembly
55' and includes a plurality of etched circuit board conductive
areas 161. These areas or paths are preselected to provide the
desired switching functions. The circuit board also includes a
plurality of aperatures 162 for receiving the contact members of
the light collector, or detector or sensitive means already
discussed. A plurality of conductive members 163 are also provided
on the circuit board to provide the electric path required by such
switch for inputing and outputing the desired switching currents.
An insulator member 165 provides insulation between circuit board
member 160 and the mounting member 170. Mounting member 170 is
similar to light collector assembly 125 except no light collector,
or detector or sensitive member is provided. Again, a spring member
180 when placed into the recess area of knob shell 50' completes
the assembly.
While there has been shown and described the preferred embodiments
of the present invention, it will be apparent to those skilled in
the art that many changes and modifications may be made without
departing from the invention in its broader aspects. For example,
two complete optoelectronic switches, say as described in FIG. 3
could be connected in a dual switch assembly. Therefore, the
appended claims are intended to cover all such changes and
modifications that fall within the true spirit and scope of the
invention.
* * * * *