US 3588420 A
Description (OCR text may contain errors)
United States Patent  Inventor Richard A. Conrad Canoga Park, Calif.
 Appl. No. 740,156
 Filed June 26, 1968  Patented June 28, 1971  Assignee Switchcratt, inc.
 ILLUMINATED PUSHBUTTON SWITCH AND Primary ExaminerH. 0. Jones Attorney-Johnston, Root, OKeeffe, Keil, Thompson and Shurtleff ABSTRACT: An illuminated pushbutton switch and potentiometer assembly is disclosed. The switch is mountable in a light transmitting panel and has a pushbutton actuator that is shielded from the light in an outer position and unshielded when in an inner position so that light is reflected from the pushbutton actuator when in its inner position. Additionally,
the pushbutton actuator is rotatably keyed to a potentiometer for controlling the potentiometer in either the inner or outer position.
POTENTIOMETER ASSEMBLY 7 Claims, 2 Drawing Figs.
 U.S.Cl 200/167  Int.C1 H0ln9/l8  FieldotSearch 200/167 );240/1(  References Cited UNITED STATES PATENTS 2,766,373 10/1956 Gebel ..240/1(E1)(X) 3,144,643 8/1964 Andersson ..200/167(A)(X) 3,163,739 12/1964 Hutt 200/167(A) till 54 PATENTEU JUN28 |97| INVENTOR.
RICHARD A. CONRAD JOSEPH H. GOLA/VT ATTORNEY ILLUMINATED PUSI'IBUTTON SWITCH AND POTENTIOMETER ASSEMBLY BACKGROUND OF THE INVENTION Field of the Invention The invention relates to an electrical switch assembly and more particularly to a pushbutton electrical switch having an illuminated pushbutton knob wherein the knob also controls a potentiometer.
Description of the Prior Art Aerospace applications require electrical apparatus having compact size, low weight, high reliability and in many cases very specific configurations. A multicircuit pushbutton switch illustrated in a patent to E. A. Jones, et al., US. Pat. No. 3,329,792, exemplifies such a switch having many desirable characteristics. Nevertheless, circumstances have developed which require switches having additional abilities than that shown in the above-mentioned patent without adding considerably to cost or lessening reliability of an already proven switch.
SUMMARY OF THE INVENTION An improved pushbutton switch, as hereinafter disclosed, solves the above-mentioned problems and provides a more adaptable switch. The switch comprises in combination a fixed electrical contact, a moveable electrical contact for selectively making and breaking engagement with the fixed electrical contact, a switch actuator connected to the moveable electrical contact for moving the moveable electrical contact and for receiving and directing light from a remote light source, and means for mounting the switch actuator and the moveable electrical contact in an operable relationship with the fixed electrical contact. Another switch embodiment comprises a fixed electrical contact, a moveable electrical contact, a potentiometer, a rotatable switch actuator for moving the moveable electrical electrical contact and for controlling the potentiometer and means for mounting the switch actuator, the moveable electrical contact, the fixed electrical contact and the potentiometer in an operable relationship. Still another switch embodiment includes in combination, both of the above-mentioned embodiments and comprises a fixed electrical contact, a moveable electrical contact, a potentiometer, a rotatable switch actuator for moving the moveable electrical contact, for controlling the potentiometer and for selectively receiving and directing light from a remote light source and means for mounting the switch actuator, the moveable electrical contact, the fixed electrical contact and the potentiometer in an operable relationship.
An object of the present invention is to provide an electrical switch assembly having a pushbutton actuator which is capable of selectively receiving and directing light provided from a remote source.
Another object of the present invention is to provide an electrical switch assembly having a pushbutton actuator capable of controlling a potentiometer.
A further object of the present invention is to provide a switch-potentiometer assembly, the switch having a pushbutton actuator which is capable of selectively receiving and directing light provided from a remote source and which is low in weight, compact and highly reliable.
Other objects and many of the attendant advantages of this invention will become more readily apparent to those skilled in the art as the same becomes better understood by reference to the following detailed description of preferred embodiments of the invention when read in connection with the accompanying sheet of drawings.
BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a cutaway, partially sectioned side view of a switch-potentiometer assembly with the pushbutton actuator shown in its outer position.
FIG. 2 is a side view of a portion of the view illustrated in FIG. I and illustrates the pushbutton actuator in its inner position.
DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to FIG. I there is illustrated a mounted pushbutton switch assembly in combination with a potentiometer in a rugged, lightweight and compact configuration and comprises a panel 10 and a pushbutton switch having a housing 12 which may be pressed fitted to the panel 10 and which is adapted to have a potentiometer 14 suitably mounted thereto. The panel is divided into the parts, a front panel 16 constructed of a light transmitting material, such as Lucite, and a back panel 18 constructed of metal to act as a support for the switch housing and the front panel 16. The light transmitting front panel 16 has two surfaces, a front surface 20 and a rear surface 22 both of which are coated with a reflecting material to prevent light from a remote source such as a small light bulb 23 (the direction of the light is exemplified by an arrow 24) from being transmitted from either the front surface 20 or the rear surface 22. Thus any light within the panel 16 will be reflected from the surfaces 20 and 22 to remain within the panel. The panel 10 has an opening therein creating a third surface 26 annular in configuration which is not coated so that light being transmitted through the panel will be directed to and through the surface 26 and thereby illuminate whatever is placed within the opening.
The switch housing 12 is comprised of two main sections, a case section 28 and a spacer section 30 keyed by a pin 31. Both of the sections may be made of insulative material or may be ofa noninsulative material provided an insulative liner (not shown) is located to separate the internal electrical contacts of the switch from the case 28 and the spacer 30. The opening which forms the surface 26 in the front panel 16 is enlarged at its rear surface 22 and extends through the rear panel 18 in its enlarged form. The rear panel 18, as mentioned above, may be of a metal having sufficient structural integrity to support the switch-potentiometer assembly and may receive the spacer 30 with a pressed fit as illustrated in FIG. I or may be attached in any other suitable fashion such as providing proper flanges and holes to receive machine screws or bolt and nut combinations (not shown).
The potentiometer 14 comprises a housing 32 containing a fixed wound resistance wire (not shown) and a shaft 34 having an adjusting rotatable contact (not shown) at one end thereof. The other end 38 of the shaft 34 extends toward the illuminated panel Ml a sufficient distance to enable it to operate in cooperation with the switch 12 as will be explained hereinafter. The extending portion of the shaft 34 is generally cylindrical in shape except for a slotted cutout 36 extending from the end 38 for bifurcating the shaft 34 into prongs 39. Located between the end 38 and the housing 32 is a threaded cylindrical element 40 upon which a nut 42 is rotatably secured to act in cooperation with a shoulder 44 to fixedly support a spring mounting bracket 46. The mounting bracket 46 has three arms 48 (only two of which are shown in FIG. I) of spring steel each having a slot 50 near its end which snaps into abutting engagement with an annular flange 52 of the case 28. Electrical terminal members 54 are connected to the potentiometer M to provide a capability to mate the potentiometer with a corresponding electrical connector. A potentiometer assembly as illustrated in FIG. 1 may be purchased from any one of several well-known sources.
Included with the switch assembly as shown in FIG. l is a moveable switch actuator 60 forming a pushbutton shaft having a variety of configurations along its length. The actuator 60 may be constructed of any suitable material such as a metal or may be constructed of the same light transmitting material as the front panel 16. One end 61 of the actuator extends beyond the panel 10 and is cylindrical in shape with serrations 62 formed longitudinally about its periphery for convenient gripping by an operator so as to enable rotation. If the actuator is metal then between the end 61 and the panel the actuator increases in diameter to form a tapered surface 64. The surface 64 is highly polished so as to have good light reflecting characteristics. At a second end 70 the actuator 60 has a flattened tongue configuration which is adapted to be slidably received by the prongs 39 of the shaft 34 within the slotted opening 36.
Disposed about the pushbutton actuator 60 is a barrier means 72 in the form ofa ring having crimp 74 designed to engage with an annular groove 66 in the actuator; longitudinal movement of the actuator 60 causes similar longitudinal movement of the barrier means 72. The barrier means 72 has an extension arm 76 positioned longitudinally about the actuator 60 and abuts a coil spring 78 which is positioned about the prongs 39 of the shaft 34 between the extension arm 76 and a base plate 77. When the actuator 60 is moved longitudinally inwardly in the direction of the potentiometer, the spring 78 provides a biasing force against the arm 76 and thereby the barrier means 72 so as to provide a force upon the actuator 60 acting in an outward direction. The barrier means 72 may be of any suitable material which is either opaque or coated with an opaque substance to prevent light which is transmitted through the front panel 16 to the surface 26 being transmitted to the actuator 60.
Positioned within the switch housing 12 and about the actuator 60, the shaft 34 and the arm 76 are fixed and moveable electrical contacts. Configured as shown in the above-mentioned patent to Jones, et al., the fixed electrical contact comprises an insulative cylindrical support 80 having a plurality of grooves 82 into which are molded a plurality of electrical contacts 84 of varying lengths depending upon the desired switching operation to be achieved. The support 80 which may be molded integral with the baseplate 77 is securely mounted in the case 28 by having a lip 83 of the case engage a flange (not shown) on the support. Each of the fixed electrical contacts 84 are integral with terminal pins 86 which are located exterior of the case 28 and the base plate 77 and are adapted to be connected to external electrical circuitry.
Moveable along the longitudinal axes of grooves 82 are a plurality of slidable electrical contacts 88 for selectively making and breaking electrical engagement with selected fixed contacts 84. The slidable contacts 88 are secured to an insulative base 90. Adjacent to and abutting the insulative base 90 is an annular cam ratchet 92 which is rotatable and moveable along the longitudinal axis of the actuator 60. The position of the cam ratchet 92 depends upon the position of an annular cam actuator 94 and the relationship to fixed guides 96 which are connected to the interior of the spacer 30. The cam actuator 94 is constrained by the fixed guides 96 to move in a direction parallel the longitudinal axis of the actuator 60. Such longitudinal movement of the cam actuator 60 which causes a corresponding movement of the barrier means 72. As illustrated in FIG. 1, the barrier means 72 is positioned adjacent the cam actuator 94 so as to bear against the cam actuator and cause it to also be depressed when the actuator 60 is depressed. The cam ratchet 92 is designed with a long, divided, slanted surface 100, a short slanted surface 102 (hidden in FIG. 1 and thereby designated with a dotted line) and a slot 104 (shown in dotted lines in FIG. 1 and thereby designated with a dotted line). The slanted surfaces 100 and 102 and the slot 104 are adapted to be engaged by either the cam actuator 94 or the fixed guides 96 during various times of the operative cycle to be explained hereinafter. More detailed descriptions and explanations of operations of the cam actuator, the cam ratchet and the fixed guides are given in the above-mentioned patent to Jones et al.
During operation of the switch it is desired that the slidable contacts 88 be able to take one of two positions: an outer or first position as shown in FIG. 1, and an inner or second position wherein the slidable contacts are located in a position closer to the base plate 77 than when in the outer position. The cam ratchet 92 and the cam actuator 94 are designed to enable the slidable contacts 88 to alternately take the two positions by simply depressing the pushbutton actuator. In the upper position as shown in FIG. 1 the cam ratchet 92 is biased by a spring 106 against the cam actuator 94 by hearing against it with the surface 100 so that the cam actuator abuts the barrier means 72. The spring 106 is disposed about the arm 76 of the barrier means and constrained between the support and the base the base 90 directly abuts the cam ratchet 92. The fixed guides 96 are located so as to ride in the slots 104 of the cam ratchet. Upon depression of the pushbutton actuator 60, the cam actuator 94, the cam ratchet 92, the vase 90, the moveable contacts 88 are longitudinally displaced toward the inner position. The cam ratchet 92 being restrained by the fixed guides 96 within the slots 104 will not rotate until the cam has been sufficiently displaced so as to disengage the fixed guides 96 from the slots 104. When the constraint is alleviated, the biasing force of the cam actuator upon the slanted surface causes the cam ratchet to rotate bringing the short slanted surface 102 into alignment with the guides 96. When the force initiating the depression of the actuator 61) is relieved, the cam ratchet 92 will be urged to return to its FIG. 1 position but will be unableto do so since the surface 102 will abut the lower end of the guide 96 leaving the cam ratchet in a substantially displaced position from that shown in FIG. 1 thereby forcing the base 90 and the slidable contacts 88 to be also displaced to the lower position. Meanwhile the pushbutton actuator 60 will remain in a depressed position as shown in FIG. 2 because the base 90 abuts a clip spring 110 disposed in a notch 112 within the arm 76.
When the pushbutton actuator 60 is depressed again, the biasing force of the cam actuator causes the cam ratchet to rotate once again so as to align the slots 104 with the fixed guides 96. Thus, when the force upon the pushbutton actuator is released, the biasing springs 78 and 106 will cause the internal assembly to be longitudinally displaced to the outer posi tion as originally shown in FIG. 1.
Referring now to the surface 64 on the actuator 60 and the barrier means 72 in FIG. 1, it is noted that the light being transmitted through the front panel 16 does not impinge upon any part of the switch actuator 60. However, referring to FIG. 2, when the switch actuator has been depressed, the barrier means 72 has been displaced from a blocking position between the surface 26 of the front panel 16 and the surface 64 so that the surface 26 acts as a light source. Light from the remote source 23 as depicted by the arrow 24 is reflected off the surface 64 (depicted by arrows which, as mentioned earlier, is highly polished. Thus, it is seen that when the slidable contacts 88 are in their outer position, the switch actuator 60 does not receive any light from the front panel 16. Whereas, when the slidable contacts are in their inner position, the switch actuator reflects the light from the front panel 16 so that to an operator viewing the panel the switch actuator appears illuminated; this quickly indicates that the switch is in its depressed or inner position.
It is to be noted that the barrier means 72 in the FIG. 1 embodiment could be eliminated by moving the surface 26 of the front panel 16 closer to the switch actuator 60 to still function very similarly to that described above. However, in a preferred embodiment the barrier means 72 is desired to provide a marked contrast between the two positions of the switch actuator 60. It is also to be noted that the switch actuator body may be of the same material as the front panel 16 so that when the barrier means 72 is longitudinally displaced the portion of the switch actuator 60 within the ring formed by the surface 26 will receive the transmitted light and give off a glow which once again indicates when the switch actuator is in its depressed position. Another embodiment may comprise placing a light transmitting cap (not shown) over the switch actuator 60 so that the light reflected from the surface 64 is diffused through the cap to indicate the position of the switch actuator.
The end of the switch actuator 60 slidably engages the slotted opening 36 of the shaft 34 in both of the positions of the switch actuator. Thus any rotation of the switch actuator will cause a corresponding rotation of the shaft 34 thereby acting to control the potentiometer 14.
Thus it is seen that a relatively compact design of low weight of proven and reliable switch configuration is being disclosed.
It is to be understood that while one embodiment has been illustrated and several variations disclosed herein for purposes of the specification, various changes can be made in the various parts of the embodiment without departing from the scope of the invention as defined by the appended claims.
1. An electrical switch, comprising:
a. a fixed electrical contact;
b. a moveable electrical contact for selectively making and breaking engagement with said fixed electrical contact;
c. a light transmitting panel opening therein for mounting said fixed and movable electrical contacts;
d. a remote light source transmitting light through said panel to said panel opening;
e. a moveable switch actuator disposed to move through said panel opening connected to said moveable electrical contact for moving said moveable electrical contact between an inner and an outer position for respectively making and breaking said engagement with said fixed electrical contact;
f. said switch actuator including opaque barrier means disposed about said switch actuator and moveable therewith for blocking said light transmitted to said panel opening from said light source through said panel when said switch actuator is in said outer position; and
g. said switch actuator including light directing means moveable therewith for directing said light transmitted from said light source through said panel and said panel opening out of said panel opening when said switch actuator is in said inner position.
2. An electrical switch, comprising:
a. a fixed electrical contact;
b. a moveable electrical contact for selectively making and breaking an engagement with said fixed electrical contact;
c. a light transmitting panel having a panel opening therein for mounting said fixed and moveable electrical contacts;
d. a remote light source transmitting light through said panel to said panel opening;
e. a potentiometer mounted below said fixed electrical contact;
f. a rotatable switch actuator passing through said panel opening and connected to said moveable electrical contact and to said potentiometer for moving said movable electrical contactbetwecn an inner and an outer position and for rotatively controlling said potentiometer;
g. said switch actuator selectively receiving and directing light from said remote light source at said panel opening when in said inner position; and
h. a moveable barrier means connected to an moveable with said switch actuator for blocking light from said remote light source at said panel opening when in said outer position.
3. An electrical switch as claimed in claim 2, wherein:
a. said switch actuator includes a light reflecting surface;
b. said barrier means comprises an opaque ring disposed about said switch actuator and disposed adjacent the opening in the light transmitting panel when said switch actuator is in said outer position;
c. said potentiometer includes a shaft having a longitudinal slot therein; and
d. said switch actuator includes an extending portion mating with said slot of said shaft.
4. An electrical switch, comprising:
a. light transmitting panel means having a mounting aperture therein;
b. a light source for passing light through said panel means and into said mounting aperture;
c. switching means mounted within said mounting aperture;
d. rotatively and longitudinally adjustable switch actuating means passing through said mounting aperture and said switching means for actuating said switchirzlg means into first and second switch positions during S81 longitudinal adjustment;
e. controllable impedance means mounted upon said switching means and controlled by said rotatable adjustment of said switch actuating means; and
f. said switch actuating means including first means, for
preventing said light from entering said mounting aperture in said first switch position and second means for directing said light from said mounting aperture in said second switch position.
5. An electrical switch as claimed in claim 4, wherein: said controllable impedance means mounted upon said switching means includes a potentiometer.
6. An electrical switch as claimed in claim 5, wherein:
said longitudinal adjustment of said switch actuating means includes an inward and outward adjustment for respectively placing said switching means in said first and said second positions;
said first means included in said switch actuating means includes an opaque ring disposed about said switch actuating means; and
said second means included in said switch actuating means includes a light reflecting surface.
7. An electrical switch as claimed in claim 6 wherein:
a. said potentiometer includes a shaft having a longitudinal slot therein; and
b. said rotatively, inwardly and outwardly adjustable switch actuating means includes an extending portion mating with said slot of said shaft whereby rotation of said switch actuating means causes rotation of said shaft of said potentiometer.
UNITED STA'HQS PATENT OFFRCLE CELEQiIFlCAIE-B OF cosmcnow Patent No. 5,588.4?9 Dated June 2S. 19E.
Inventor(5) PL iChal'd. A. COHI'HK].
It is certified that error appears in the above-identified patent and that: said Letters Patent are hereby corrected as shown below:
Column line 10, "vase" should read "and" should read end 70 base line 71,
Column 5, line 52, "an" should read and Signed and sealed this 29th day of February 1972.
EDWARD PLFLETCHEH, Jli. ROBERT GOTTSCHALK Attesting Officer- Commissioner of Patents