US3560906A - Infinitely variable electronic device - Google Patents

Abstract

TWO ELECTRICAL ELEMENTS ARE MOUNTED FOR INDEPENDENT ROTATION IN THE SAME DIRECTION ABOUT A COMMON AXIS AND, AS A RESULT OF THE ROTATION, A LONGITUDINAL DISPLACEMENT WITH RESPECT TO EACH OTHER, SAID ELEMENTS BEING IN ELECTRICALLY COACTIVE RELATIONSHIP WHEREBY ELECTRICAL VALUES DEPEND UPON THE LONGITUDINAL DISPLACEMENT CAUSED BY THE ROTATION OF THE TWO ELEMENTS.

Description

Feb. 2, 1971 E. c. WAHLBERG 3,560,906

- INFINITELY VARIABLE ELECTRONIC DEVICE Filed 001;. 28, 1968 Illl Patented Feb. 2, 1971 3,560,906 INFINITELY VARIABLE ELECTRONIC DEVICE Eric C. Wahlberg, 32 8th St., Stamford, Conn. 06905 Filed Oct. 28, 1968, Ser. No. 771,126 Int. Cl. H01c /02, I/02 U.S. Cl. 338-145 6 Claims ABSTRACT OF THE DISCLOSURE This invention relates to electronic devices normally known as potentiometers, variable resistors, variable condensors, trimmers, variable impedances and the like. In particular, as described herein but not limited thereto, the invention relates to providing a simple, economical, miniature assembly which will result in providing extremely accurate electrical values for electronic and other devices.

An object of the invention is to provide a means whereby the pickoff contact follows each minute increment of the length of the resistive layer thus providing extreme accuracy.

Another object is to provide a product which is vibration and shock proof and will not lose its accurate setting under such conditions.

Another object of the invention is to provide a product with a minimum of parts designed for simple and quick assembly. Another object of this invention is to provide a product which is adaptable to incorporating a single electrical characteristic or a multiple of the same or difierent characteristics into one unit.

Further objects of the invention will become apparent from the broad interpretation of the specification and the drawings.

These and other objects of the invention are achieved in an arrangement wherein two cylinders, each having a body and a flange at one end of the body, the flanges being of different diameters but larger than the respective body diameters, are free to rotate about a common shaft center. The circumference of the body of one cyclinder has a thread which mates with an internal thread of the body of the second cylinder. When the flanges of the two cylinders are mated with a third member having correspondingly different diameters, a rotation of the two cylinders with respect to each other may be caused by the turning of the third member. The radius of one flange added to the radius of that portion of the third member which cooperates with that flange must equal the radius of the other flange added to the radius of that portion of the third member which cooperates with that flange, and, as a result, the relative speed of rotation of one cylinder with respect to the other cylinder will be determined by the ratio between their respective radii. The net effective result of the difference in speed will be translated into a longitudinal displacement of the two cylinders relative to each other. Proper mounting of the conducting components and the one cylinder and sliding pick-off on the mating cylinder coact together with terminals, cylinder shafts and pinion shaft to provide an assembly which may be compactly contained in a housing to form a completed product according to this invention.

One embodiment of this invention is illustrated in FIGS. 1-5 in which:

FIG. 1 illustrates a front view of the complete unit;

FIG. 2 is a view showing the assembly in a cutaway of the housing;

FIG. 3 is a top view with the cover removed;

FIG. 4 is a cross section of the two cylinders and their components as they relate to the assembly in a cross section of the housing along line 4-4 of FIG. 3;

FIG. 5 is a cross section taken along line '55 of FIG. 4; and

FIG. 6 is a cross section view of segment of the cylinder and drive assembly illustrating a second embodiment.

Other embodiments of this invention are afforded with variable condensers, impedances, etc., as well as multiple electrical components operated by one drive member in which mounting of the rotary and stationary parts on the respective cylinders is accomplished so that when they are rotated they are properly identified with each other as to electrical properties and mechanically. It is important therefore not to limit the scope of the invention to those embodiments illustrated but to consider it in the broad aspect.

Reference is now made to FIG. 4 which illustrates the parts involved in the assembly of the embodiment. Included in the embodiment is case 50 with cover 6, shaft 24, lower cylinder 14, upper cylinder 33, pinion shaft 16, terminals 7, 21, 20, sliding contacts 15, 28, 27, conductive layers 23 and 25, and resistive layer 10 in the root of the worm teeth 9. Cylinders 14, 33, pinion 16, shaft 24, housing 50 and cover 6 are made of insulating material.

Sliding contact 15 is mounted in longitudinal groove 34 on the circumference of cylinder 14. One end contacts conductive layer 10 in the threaded circumference of cylinder 33. The threads are deep enough so that when the resistance is in place at the root of the thread the mating thread of cylinder 14 does not extend against the resistance path or layer. The other end of slide contact 15 extends under the cylinder 14 and around the insulator 19. An extruded washer 18, FIG. 5 having four equally spaced fingers 30 biased upwardly so that when the parts are in place there will be a spring action against the bottom of the case to force the cylinder assembly together against the cover and to assure good contact between the washer and the sliding contact extension 31. The washer has a tubular extension projecting downwardly to form a contact 20 which extends out of the case 50. The resistive layer 9 is deposited in the root of the thread on the circumference of cylinder 33. A sliding contact 28 is snapped around the lower end of cylinder 33 holding the lower end of the resistive layer. The other end is in slidable contact with conductive layer 23 surrounding the lower end of insulating shaft 24. The conductive layer 23 has an extension which forms a terminal 21 and extends through the bottom of cylinder 14 and contact 20 which is insulated from terminal 21 by tube 19. Another sliding contact 27 is snapped around the upper end of cylinder 33. One end is attached to the upper end of the resistive layer and the other end is in slidable contact with conductive layer 25 surrounding the upper end of the insulated shaft 24. An enlargement 29 of the diameter of insulating shaft 24 separates the conducting layers 23 from 25. The con ductive layer 25 has an extension which forms a terminal 7 extending out of the cover 6. Thus, two terminals extend out of the bottom of the case and the third terminal extends out of the cover of the case and are stationary.

A circuit is made from terminal 7 through conductive layer 25, contact 27, resistive layer 10, slidable contact 15, washer 18 to contact 20. Also a circuit is made from terminal 7, conductive layer 25, contact 27, resistive layer 10, contact 28, conductive layer 23 and terminal 21. The amount of resistance included in the first path is determined by the position of contact 15 on the resistive layer 10. This in turn is dependent on the relative longitudinal positions of the cylinders 14 and 33. Their positions are determined by the turning of the pinion shaft 16.

Cylinder 33 has a thread on its circumference whose teeth 9 mate and coact with thread teeth 26 on the inner wall of the lower cylinder 14. The upper cylinder also has a flange extending outwardly from the upper end of the cylinder. This flange has spur teeth 8 which rotatably and slidably mate with teeth 11 on pinion shaft 16. The lower cylinder 14 also has a set of spur teeth located tround the circumference of the upper end of the cylinder. These teeth mate with a second set of teeth 12 on the pinion 16. The teeth 11 are located on a diameter which is larger than the diameter on which gear teeth 12 are located. The gear teeth on the larger diameter of the pinion are mated with the gear teeth on the smaller cylinder, in the upper cylinder 33. The gear teeth on the smaller diameter of the pinion shaft 16 are mated to the teeth on the large diameter cylinder 14. In each case the sum of the pitch radii of the pinion and the cylinder gear teeth must equal the center distance between the pinion shaft 16 center and insulated shaft 24 center. Thus, when the pinion shaft is turned by means of extension 17, both cylinders will rotate and in proportion to the circumferences of the mating gears. The larger cylinder 14 will turn slower than the smaller cylinder 33. Thus, though both cylinders are rotating, the smaller cylinder 33 will be going faster and, after a predetermined number of turns of the pinion shaft 16, will lap cylinder 14.

Since cylinder 33 Will be turning faster than cylinder 14, cylinder 33 will screw itself down into cylinder 14 by means of the coaction of teeth 9 On cylinder 33 and teeth 26 on cylinder 14 as they are mated. Thus, with proper design, very high accuracy may be obtained from small increments of rotation of the pinion shaft applied to displace the cylinders 14 and 33 angularly and consequentially, longitudinally.

An extension 22 on one end of the pinion shaft 16 is provided as a bearing surface in the bottom of the case 5. At the other end of the pinion an extension 17 is provided as a second bearing to fit into opening in cover 6. This extension is a means for applying motion to the pinion either manually or by motor drives etc. for remote control.

The above parts are assembled into case equipped with cover 6.

By providing threads the entire length of the inside of the lower cylinder and by placing a conductive path in the root of the thread of the upper cylinder and by connecting contact directly to the aforementioned conductive path in the lower cylinder 14, a condenser is effected.

Another means of obtaining condenser action is to provide a conductive path inside of the upper cylinder 33 and removing contact 28. In this way an electrical coaction obtained between the conductive path on the inside of the upper cylinder and the conductive path 23 of the shaft 24.

Several combinations may be obtained by the use of both conductive, inductive and noninductive electrical material mounted on the cylinders to coact to give the desired electrical characteristics.

To those skilled in the art, it will be readily understood that a plurality of sets of mating cylinders, such as 14 and 33, with their components may be rotated simultaneously by mating with the respective gear teeth of the pinion shaft 16 and by rotating the pinion shaft 16; that a number of combinations of speeds may be developed with proper design of coacting components; that a number of electrical characteristics capable of being varied by the application of this concept may be obtained all as required to fulfill the specific design criteria.

The operation of the described embodiment is simple. An electrical power source is connected across terminals 7 and 21. As shaft extension 17 is turned in one direction, the cylinder 33 will be caused to rotate by gear 11 and 8 around shaft 24. Cylinder 14 will also be caused to rotate by gears 12 and 13 about shaft 24. Cylinder 14 will rotate at a lesser speed rate than cylinder 33. The difference of rates of speed is translated into a longitudinal motion of cylinder 33 into cylinder 14 through the action of thread 9 of cylinder 33 against thread 26 of cylinder 14. Since cylinder 14 is restricted in its longitudinal motion by its position between the bottom of the case and the shoulder of the end of the shaft 24, all the longitudinal motion is accomplished by cylinder 33. Therefore, gear 8 will move longitudinally along pinion gear 11 a proportionate amount as it rotates with gear 11. Further, contacts 27 and 28 move around angularly and longitudinally along the conductive coatings 25 and 23 respectively on shaft 24 so that continuity of power is preserved to resistive layer 10. As cylinders 14 and 33 rotate and move longitudinally, sliding contact 15 in cylinder 14 follows the resistive layer and monitors the electrical change that takes place. This change is transmitted to terminal 20 so that an electrical value may be continually obtained across terminals 7 and 20 or 20 and 21.

When the extension 17 of pinion shaft 16 is in the opposite direction, cylinders 33 and 14 will reverse their operation and the same terminals will indicate the change in the direction by an appropriate change in electrical output.

Referring to FIG. 6, which illustrates, when taken in combination with FIG. 4, another embodiment of the invention. Included in the embodiment is a case 50, cover 6, shaft 240, lower cylinder 14, upper cylinder 330, pinions 11 and 12, and lock ring 51. Like numerals designate like parts in both embodiments illustrated.

Cylinder 330 has a thread on the circumference of its lower portion whose teeth 9 mate and coact with thread teeth 26 on the inner wall of the lower cylinder 14. The upper cylinder also has a flange extending outwardly from the central portion of the cylinder. This flange has spur gear teeth 8 rotatably and slidably mating with teeth 11 on pinion shaft 16 of FIG. 4. The upper cylinder extends out of the cover 6 and is fitted on its outer end with a connecting tongue 55 having a pin 53 as a means for connectrng to some such mechanism 54. Upper cylinder 330 1s provided with an internal bore which provides means for mounting allowing angular and longitudinal motion on shaft 240.

The lower cylinder 14 also has a set of teeth 13 located around the circumference of the upper end of the cylinder. These teeth mate with a second set of teeth 12 on the pinion 16. The lower cylinder is mounted on a smaller diameter at the end of shaft 240.

The entire assembly of the upper and lower cylinders and the pinion is mounted in the case 50 by means of the shaft 240 extending through the bottom of case 50. A snap ring 51 is placed in groove 52 of shaft 240 to anchor the assembly in the case 50. A cover 6 is provided to enclose assembly allowing only the extension of the pinion shaft and the extension of the upper cylinder 330 to protrude.

The interaction and resultant displacement of the two cylinders by the motion of the pinion is the same as for the embodiment previously described and is therefore not repeated.

However, the resultant longitudinal and angular displacement of the upper cylinder 330 provides a means for operating various devices which require accurate straight line or a combination of straight line and rotary motion.

There accordingly have been shown and described herein novel means for obtaining highly accurate positioning means for obtaining highly accurate positioning of various items particularly of mechanical, electronic or electrical nature but not limited thereto. There has been described and shown a novel means of accurately rotating two or more items at relative speeds to each other and to accurately displace each other longitudinally with regard to each other. There has also been described a means for obtaining accurate electrical values by accurately and infinitely varying the relative positions of coacting electrical elements. There has also been described a means of employing a plurality of such devices operated from one input.

While I have described several embodiments of my invention in this application, it is not the intent to limit the scope of the invention to these embodiments as there are other embodiments that may be made by those skilled in the art without departing from the concept of the invention.

What I claim is:

1. A device for connection in an electrical circuit for adjusting to a selected electrical value from a multiplicity of electrical values in said circuit, comprising a housing, a pair of elements mounted in said housing in electrical coactive relationship with each other and independently rotating while in said coactive relationship about a common axis and for motion longitudinally with respect to each other, each of said multiplicity of electrical values being a function of the relative angular and longitudinal displacement of said pair of elements, and driving means for simultaneously rotating both of said pair of elements in the same direction, said driving means including a rotatable drive member engageable with each of said pair of elements for angular displacement of, said elements in response to rotation of said drive member, means for longitudinally displacing said pair of elements with respect to each other in response to the rotation of each of said elements by said drive member, the rate of longitudinal displacement of said pair of elements with respect to each other being determined by the difference of the angular rate of each of said pair of elements.

2. The device as defined in claim 1 wherein the first one of said pair of elements comprises a cylindrical shaped body mounted for rotation about a central axis having a threaded peripheral surface, a resistive layer disposed in said peripheral surface, and the second one of said pair of elements comprising a cylindrical body having an internal thread coacting with the threads of said first one of said pair of elements for longitudinal movement relative to each other, said second pair of elements includes contact means rotatable therewith and in electrical operative engagement with said resistive layer.

3. The device as defined in claim 1 wherein said drive means includes a pair of coaxial gear means mounted on an axis parallel with said common axis each having a different radius, and a pair of driven gear means of unequal radii in driven engagement with the first pair of gear means, and means for operatively connecting each 6 of said driven gear means with a respective one of said first mentioned pair of elements.

4. The device as defined in claim 1 wherein each of said pair of elements comprises a cylindrically shaped body rotating about its central axis, and said driving member is rotating about an axis parallel with said common axis of rotation of the pair of elements, said driving element having two circumferential portions of unequal radii, and means for driving engagement between said driving portions and a circumferential portion of a respective cylindrical shaped element, the sum of the radius of one driving portion and the radius of a respective element being equal to the sum of the radius of the other driving portion and the radius of the other respective element.

5. The device as defined in claim 4 wherein said two drive portions comprise spur gears, and the circumferential portions of the pair of elements include teeth for meshing engagement with said spur gears.

6. A device for connection to a mechanism for adjusting to a selected electrical value from a multiplicity of electrical values in said mechanism, comprising a housing, a pair of elements mounted in said housing in coactive relationship with each other and independently rotating while in said coactive relationship about a common axis and for motion longitudinally with respect to each other, each of said multiplicity of electrical values being a function of the relative angular and longitudinal displacement of said pair of elements, and driving means simultaneously rotating both of said pair of elements in the same direction, said driving means including a rotatable drive member engageable with each of said pair of elements for angular displacement of said elements in response to rotation of said drive member, means for longitudinally displacing said pair of elements with respect to each other in response to the rotation of each of said elements by said drive member, the rate of longitudinal displacement of said pair of elements with respect to each other being determined by the diflerence of the angular rate of rotation of each of said pair of elements.

References Cited UNITED STATES PATENTS 2,785,261 3/1957 Roberts 338157X 3,109,317 11/1963 Cousino 7441l 3,360,757 12/1967 Wahlberg 338-162 LEWIS H. MYERS, Primary Examiner G. P. TOLIN, Assistant Examiner US. Cl. X.R. 338-146, 162, 174

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