[go: up one dir, main page]

US3851293A - Electrical resistance element and method of manufacture - Google Patents

Electrical resistance element and method of manufacture Download PDF

Info

Publication number
US3851293A
US3851293A US00280809A US28080972A US3851293A US 3851293 A US3851293 A US 3851293A US 00280809 A US00280809 A US 00280809A US 28080972 A US28080972 A US 28080972A US 3851293 A US3851293 A US 3851293A
Authority
US
United States
Prior art keywords
resistance film
path
film element
wiper
high resistance
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US00280809A
Inventor
J Clayton
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
WATERS Manufacturing Inc
Original Assignee
WATERS Manufacturing Inc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by WATERS Manufacturing Inc filed Critical WATERS Manufacturing Inc
Priority to US00280809A priority Critical patent/US3851293A/en
Application granted granted Critical
Publication of US3851293A publication Critical patent/US3851293A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01CRESISTORS
    • H01C10/00Adjustable resistors
    • H01C10/04Adjustable resistors with specified mathematical relationship between movement of resistor actuating means and value of resistance, other than direct proportional relationship
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10TTECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T29/00Metal working
    • Y10T29/49Method of mechanical manufacture
    • Y10T29/49002Electrical device making
    • Y10T29/49082Resistor making
    • Y10T29/49099Coating resistive material on a base

Definitions

  • ABSTRACT [22] F1led: ,Aug. 15,1972
  • Non-linear potentiometers are potentiometers which include an electrical resistance element of either plane or cylindrical configuration along which a wiper is moved to provide a voltage output value which varies non-linearly as a predetermined mathematical function of the distance from an end termination of the resistance element.
  • the rate of change of voltage output to distance causes the voltage output value near one end of the resistance element to be large compared to that near the other end of the resistance element.
  • a precision potentiometer having a predetermined function comprising a high resistance element, the slope of which approximates closely the maximum slope of the predetermined function, preferably a conductive plastic film on'a suitable insulating base and having end terminations.
  • the high resistance element provides a path of wiper travel between the end terminations for a wiper movable along the path.
  • a low resistance element the slope of which approximates closely the minimum slope of the predetermined function, of varying transverse cross sectional dimension, preferably a film, in continuous electrical contact with the high resistance element, extending between the end terminations in continuous parallel electrical connection with the high resistance element, so that the high and low resistance elements together provide a voltage output value at the wiper varying as a predetermined function of distance from one end termination, either non-linearly or linearly.
  • Slope ratios as high as 100,000:l may be achieved by the invention.
  • the low resistance element is spaced from the wiper path and has its edge remote from the wiper path at a varying distance from the adjacent edge to provide the varying transverse cross sectional dimension.
  • the edge of the low resistance element adjacent the path of wiper travel is diffused progressively transversely.
  • the novel method of the invention comprises the steps of providing a longitudinally extended high resistance element having end terminations, the high resistance element having a path of wiper travel between the end terminations.
  • a longitudinally extended low resistance film is provided on the high resistance element in continuous parallel electrical connection therewith extending between the end terminations.
  • the low resistance film is spaced from the wiper path.
  • the transverse cross sectional dimension of the low resistance element is then progressively altered as a function of desired voltage output value and distance from the end termination by progressively sensing the voltage output value along the path of wiper travel and altering the transverse cross sectional dimension of the low resistance value responsively thereto.
  • this is done by effectively varying the transverse dimension of the films on the side thereof remote from the path of wiper travel to provide a precision potentiometer element non-linearly varying as a function of distance from one end termination, or to provide a precision linear potentiometer.
  • FIG. 1 is a plan view of a precision potentiometer according to the invention
  • FIG. 2 is a side view of the potentiometer of FIG. 1;
  • FIG. 3 is a cross sectional end view of the potentiometer of FIG. 1, taken on line 3-3 thereof and illustrating the method of the invention;
  • FIG. 4 is an equivalent circuit diagram of a potentiometer of the invention.
  • FIG. 5 is a graph of a non-linear resistance function typical of a potentiometer of the invention.
  • the potentiometer of the present invention comprises a suitable insulating base 12 having a longitudinally extended high resistance film 14 on it.
  • Film 14 may be of any suitable material, such as a conductive plastic, for example, having a relatively high resistance value.
  • Conventional end terminations 16 and 18 are provided on opposite ends of high resistance film 14.
  • a longitudinally extended low resistance film 20 is provided on high resistance film 14 for about half the transverse dimension thereof extending between end terminations 16, 18 in continuous parallel electrical connection with high resistance film 14. High resistance film 14 is thus exposed for about half its width to provide a path of travel between end terminations 16, 18 for a conventional wiper 22 movable along said path.
  • Low resistance film 20 may be of any suitable material, such as a conductive plastic, for example, having a relatively low resistance value, and preferably has its edge 24 adjacent the path of wiper 22 diffused progressively transversely to increase the resistance value thereof in a transverse direction toward said path and spaced from said wiper path.
  • base 12 is about 5 mils thick
  • high resistance film 14 is about 1 mil thick
  • low resistance film 20 is about 1 mil thick
  • the edge 15 of high resistance film 14 and the edge 21 of low resistance film 20, that is, their opposite edges remote from the path of wiper 22 are at a varying distance from the low resistance film edge 24 adjacent the path of wiper 22 to provide a varying cross sectional dimension thereof.
  • the equivalent circuit of the potentiometer of the invention is shown in FIG. 4 to consist of a network of two parallel series of resistors connected at indefinitely short intervals along their lengths.
  • the potentiometer of the invention whether of the plane configuration as shown or of a conventional cylindrical configuration, has its wiper 22 moved along its path between terminations 16, 18 to provide the desired voltage output value, such as that of FIG. 5, for example.
  • the method of making the potentiometer element of the invention comprises the previously described steps of providing on base 12 a longitudinally extended high resistance film 14 having end terminations 16, 18 on opposite ends thereof and providing a path of travel of wiper 22 between said end terminations with a longitudinally extended low resistance film 20 on high resistance film 14 in continuous electrical contact therewith extending between said end terminations in continuous parallel electrical connection with said high resistance film and spaced from said wiper path.
  • both low resistance film 20 and high resistance film 14 are cut by a suitable cutter 30, such as an etching tool, responsive to the voltage output value E at the wiper 22 as it is moved along the wiper path in synchronism with cutter 30.
  • the invention can be equally applied to linear elements in that the use of the double film permits extension of the resistance range in the lower direction, since the lower resistance film becomes the resistance and shunt that controls the total, resistance of the entire element. In many cases, too, the lower resistance film has a high metallic content and thus has a difficult surface condition that may affect adversely the linear factors of the sliding contact.
  • a potentiometer having a predetermined function comprising a longitudinally extended conductive plastic high resistance film element having end terminations on opposite ends thereof,
  • said high resistance film element providing a path of wiper travel between said end terminations a wiper movable along said path a longitudinally extended conductive plastic low resistance film element superimposed on said high resistance film element in continuous electrical contact therewith extending between said end terminations in continuous parallel electrical connection with said high resistance film element,
  • said low resistance film element being spaced from said path of wiper travel and having an edge remote from said path of wiper travel of varying dimension from its opposed edge to provide a varying transverse dimension thereof said high and low resistance film elements together providing a voltage value at said wiper varying as a function of distance between said end terminations.
  • a potentiometer having apredetermined function comprising 7 an insulating base a longitudinally extended conductive plastic high resistance film element on said base having end terminations on opposite ends thereof,
  • said high resistance film element providing a path of wiper travel between said end terminations a wiper movable along said path, a
  • sistance film element superimposed on said high resistance film on the side thereof opposite said base and in continuous electrical contact therewith extending between said end terminations in continuous parallel electrical connection with said high resistance film element
  • said low resistance film element being spaced from said path of wiper travel and having its edge adjacent said path of wiper travel diffused progressively transversely to increase the resistance value thereof in a transverse direction toward said path' of wiper travel and spaced therefrom,
  • the methodof making a potentiometer element having a predetermined function comprising the steps of providing an insulating base a longitudinally extended conductive plastic high resistance film element having end terminations on said base said high resistance film element having a maximum voltage output slope that closely approximates the slope of said predetermined function said high resistance film element having a path of wiper travel between said end terminations and a longitudinally extended conductive plastic low resistance film element superimposed on said high resistance film element on the side thereof opposite said base and in continuous electrical contact therewith extending between said end terminations in continuous parallel electrical connection with said high resistance film element said low resistance element having a slope which approximates the minimum slope of said predetermined function said low resistance film being spaced from said path of wiper travel and progressively altering the transverse cross sectional dimension of at least said low resistance film element as a function of desired voltage output value and distance from said end terminations by progressively sensing the voltage output value along said path of wiper travel and altering the transverse cross sectional dimension of said low resistance value responsively thereto by effectively varying the transverse dimension of
  • a potentiometer having a predetermined function comprising an insulating base a longitudinally extended conductive plastic high resistance film element on said base having end terminations on opposite ends thereof,
  • said high resistance film element providing a path of wiper travel between said end terminations a wiper movable along said path
  • said low resistance film element being spaced from said path of wiper travel and having its edge remote from said path of wiper travel of varying dimension from its edge adjacent said path of wiper travel to provide a varying transverse dimension thereof said high and low resistance elements together providing a voltage output value at said wiper varying as a predetermined function of distance between said end terminations said high resistance film element having a slope which approximates the maximum slope of said predetermined function and said lowresistance film element having a slope which approximates the minimum slope of said predetermined function.

Landscapes

  • Engineering & Computer Science (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Adjustable Resistors (AREA)

Abstract

A conductive plastic potentiometer with an electrical resistance element having two end terminations and comprising two resistance films applied on a single substrate. The two films are applied sequentially with the higher resistance film being first applied over the entire substrate surface, and then a second film of substantially lower resistance being applied over the first film such as to cover and contact approximately half of the higher resistance film, so that the wiper runs on the surface of the higher resistance film.

Description

United States Patent 1191 Clayton [111 3,851,293 145 Nov. 26, 1974 ELECTRICAL RESISTANCE ELEMENT AND METHOD OF MANUFACTURE 3.379.567 4/1968 Wright 338/195 X 75 I t I h Cl t St a M Primary Examiner-J. V Truhe 1 J0 n ay Owe ass Assistant Examiner-David A. Tone [73] Asslgneez Waters Manufacturing, Inc.,
Wayland, Mass. [57] ABSTRACT [22] F1led: ,Aug. 15,1972
A conductive plastic potent1ometer with an electrical H p N01 280,809 resistance element having two end terminations and comprising two resistance film's applied on a single 1521 Us. Cl 338/195, 338/142, 29/620 Substrate The two films are applied Sequehhahy with 511 Int. Cl H010 9/02 the higher resistance film being first applied over the 5 Field f Search H 338/195 89 90 91 122 entire substrate surface, and then a second film of sub- 33g/138, 39 29/620 stantially lower resistance being applied over the first film such as to cover and contact approximately half 5 References Cited of the higher resistance film, so that the wiper runs on UNITED STATES PATENTS the surface of the higher resistance film.
2,759,078 8/l956 Brown 338/195 X 8 Claims, 5 Drawing Figures ELECTRICAL RESISTANCE ELEMENT AND METHOD OF MANUFACTURE This invention relates to precision non-linear and linear conductive plastic film potentiometers and methods of their manufacture.
Non-linear potentiometers are potentiometers which include an electrical resistance element of either plane or cylindrical configuration along which a wiper is moved to provide a voltage output value which varies non-linearly as a predetermined mathematical function of the distance from an end termination of the resistance element. In the case of certain functions, for example a logarithmic function, the rate of change of voltage output to distance causes the voltage output value near one end of the resistance element to be large compared to that near the other end of the resistance element. This is a serious problem in the design of resistance elements of the conductive film type, since it makes necessary the use of a longitudinal series of resistance elements of differing resistance values in order to keep the transverse dimensions of the resistance elements within practical limits while providing a minimum transverse dimension sufficient to be useful as a wiper path of travel. I
In view of these problems, it is a major object of the present invention to provide a novel precision nonlinear potentiometer of practical transverse dimension without the necessity of utilizing a longitudinally averaged series of resistance elements.
It is also an object of the invention to provide anovel precision linear potentiometer.
It is another object of the invention to provide a novel method of manufacturing such potentiometers.
According to the invention in its broadest aspect, there is provided a precision potentiometer having a predetermined function comprising a high resistance element, the slope of which approximates closely the maximum slope of the predetermined function, preferably a conductive plastic film on'a suitable insulating base and having end terminations. The high resistance element provides a path of wiper travel between the end terminations for a wiper movable along the path. There is also provided a low resistance element, the slope of which approximates closely the minimum slope of the predetermined function, of varying transverse cross sectional dimension, preferably a film, in continuous electrical contact with the high resistance element, extending between the end terminations in continuous parallel electrical connection with the high resistance element, so that the high and low resistance elements together provide a voltage output value at the wiper varying as a predetermined function of distance from one end termination, either non-linearly or linearly. Slope ratios as high as 100,000:l may be achieved by the invention.
Preferably, the low resistance element is spaced from the wiper path and has its edge remote from the wiper path at a varying distance from the adjacent edge to provide the varying transverse cross sectional dimension. Preferably, too, the edge of the low resistance element adjacent the path of wiper travel is diffused progressively transversely.
The novel method of the invention comprises the steps of providing a longitudinally extended high resistance element having end terminations, the high resistance element having a path of wiper travel between the end terminations. A longitudinally extended low resistance film is provided on the high resistance element in continuous parallel electrical connection therewith extending between the end terminations. The low resistance film is spaced from the wiper path. The transverse cross sectional dimension of the low resistance element is then progressively altered as a function of desired voltage output value and distance from the end termination by progressively sensing the voltage output value along the path of wiper travel and altering the transverse cross sectional dimension of the low resistance value responsively thereto. Preferably this is done by effectively varying the transverse dimension of the films on the side thereof remote from the path of wiper travel to provide a precision potentiometer element non-linearly varying as a function of distance from one end termination, or to provide a precision linear potentiometer.
For the purpose of more fully explaining the above and still further objects and features of the invention, reference is now made to the following detailed description of a preferred embodiment of the invention, together with the accompanying drawings, wherein:
FIG. 1 is a plan view of a precision potentiometer according to the invention;
FIG. 2 is a side view of the potentiometer of FIG. 1;
FIG. 3 is a cross sectional end view of the potentiometer of FIG. 1, taken on line 3-3 thereof and illustrating the method of the invention; FIG. 4 is an equivalent circuit diagram of a potentiometer of the invention, and
FIG. 5 is a graph of a non-linear resistance function typical of a potentiometer of the invention.
Referring to the drawings, in which the thickness of the film layers has been greatly exaggerated for clarity, the potentiometer of the present invention comprises a suitable insulating base 12 having a longitudinally extended high resistance film 14 on it. Film 14 may be of any suitable material, such as a conductive plastic, for example, having a relatively high resistance value. Conventional end terminations 16 and 18 are provided on opposite ends of high resistance film 14.
A longitudinally extended low resistance film 20 is provided on high resistance film 14 for about half the transverse dimension thereof extending between end terminations 16, 18 in continuous parallel electrical connection with high resistance film 14. High resistance film 14 is thus exposed for about half its width to provide a path of travel between end terminations 16, 18 for a conventional wiper 22 movable along said path.
Low resistance film 20 may be of any suitable material, such as a conductive plastic, for example, having a relatively low resistance value, and preferably has its edge 24 adjacent the path of wiper 22 diffused progressively transversely to increase the resistance value thereof in a transverse direction toward said path and spaced from said wiper path.
In the preferred embodiment, base 12 is about 5 mils thick, high resistance film 14 is about 1 mil thick, and low resistance film 20 is about 1 mil thick.
In order to provide a voltage output value at wiper 22 varying as a predetermined function of distance between end terminations 16, 18, the edge 15 of high resistance film 14 and the edge 21 of low resistance film 20, that is, their opposite edges remote from the path of wiper 22, are at a varying distance from the low resistance film edge 24 adjacent the path of wiper 22 to provide a varying cross sectional dimension thereof. The equivalent circuit of the potentiometer of the invention is shown in FIG. 4 to consist of a network of two parallel series of resistors connected at indefinitely short intervals along their lengths.
In operation, the potentiometer of the invention, whether of the plane configuration as shown or of a conventional cylindrical configuration, has its wiper 22 moved along its path between terminations 16, 18 to provide the desired voltage output value, such as that of FIG. 5, for example.
The method of making the potentiometer element of the invention comprises the previously described steps of providing on base 12 a longitudinally extended high resistance film 14 having end terminations 16, 18 on opposite ends thereof and providing a path of travel of wiper 22 between said end terminations with a longitudinally extended low resistance film 20 on high resistance film 14 in continuous electrical contact therewith extending between said end terminations in continuous parallel electrical connection with said high resistance film and spaced from said wiper path.
In order to alter progressively the transverse cross sectional dimension of at least the low resistance film 20 as a function of desired voltage output value and distance from the end terminations 16, 18 by effectively varying the transverse dimension of said film on the edge 21 thereof remote from the path of travel of wiper 22, both low resistance film 20 and high resistance film 14 are cut by a suitable cutter 30, such as an etching tool, responsive to the voltage output value E at the wiper 22 as it is moved along the wiper path in synchronism with cutter 30. This may be accomplished by applying a constant voltage across end terminations 16, 18 and measuring the voltage value E at wiper 22 by a suitable voltmeter 32, and simultaneously advancing cutter and wiper 22 at equal longitudinal distance D from end termination 16 while simultaneously moving cutter 30 transversely in accordance with the desired function of voltage and distance, as illustrated, for example in the graph of FIG. 5. As shown, the excess material of both the high and low resistance films is effectively removed from the potentiometer in an electrical sense, since cutter 30 extends into the insulating base 12. Of course, the cut could be made through the base for physical removal of excess film material if so desired.
The invention can be equally applied to linear elements in that the use of the double film permits extension of the resistance range in the lower direction, since the lower resistance film becomes the resistance and shunt that controls the total, resistance of the entire element. In many cases, too, the lower resistance film has a high metallic content and thus has a difficult surface condition that may affect adversely the linear factors of the sliding contact.
What is claimed is:
1. A potentiometer having a predetermined function comprising a longitudinally extended conductive plastic high resistance film element having end terminations on opposite ends thereof,
said high resistance film element providing a path of wiper travel between said end terminations a wiper movable along said path a longitudinally extended conductive plastic low resistance film element superimposed on said high resistance film element in continuous electrical contact therewith extending between said end terminations in continuous parallel electrical connection with said high resistance film element,
said low resistance film element being spaced from said path of wiper travel and having an edge remote from said path of wiper travel of varying dimension from its opposed edge to provide a varying transverse dimension thereof said high and low resistance film elements together providing a voltage value at said wiper varying as a function of distance between said end terminations.
2. A potentiometer as claimed in claim 1 wherein the edge of said low resistance element adjacent to said path of wiper travel is diffused progressively transversely.
3. A potentiometer as claimed in claim 1 wherein said high resistance element has a slope which approximates the maximum slope of said predetermined function and said low resistance element has a slope which approximates the minimum slope of said predetermined function.
4. A potentiometer having apredetermined function comprising 7 an insulating base a longitudinally extended conductive plastic high resistance film element on said base having end terminations on opposite ends thereof,
said high resistance film element providing a path of wiper travel between said end terminations a wiper movable along said path, a
a longitudinally extended conductive plastic low .re-
sistance film element superimposed on said high resistance film on the side thereof opposite said base and in continuous electrical contact therewith extending between said end terminations in continuous parallel electrical connection with said high resistance film element,
said low resistance film element being spaced from said path of wiper travel and having its edge adjacent said path of wiper travel diffused progressively transversely to increase the resistance value thereof in a transverse direction toward said path' of wiper travel and spaced therefrom,
the opposite edges of said films remote from said wiper path being of varying dimension from said adjacent edge to provide a varying transverse dimension thereof said high and low resistance elements together providing a voltage output value at said wiper varying as a predetermined function of distance between said end terminations said high resistance film element having a slope which approximates the maximum slope of saidpredetermined function and said low resistance film element having a slope which approximates the minimum slope of said predetermined function. 5. A potentiometer as claimed in claim 4 wherein said predetermined function is non-linear.
6. The methodof making a potentiometer element having a predetermined function comprising the steps of providing an insulating base a longitudinally extended conductive plastic high resistance film element having end terminations on said base said high resistance film element having a maximum voltage output slope that closely approximates the slope of said predetermined function said high resistance film element having a path of wiper travel between said end terminations and a longitudinally extended conductive plastic low resistance film element superimposed on said high resistance film element on the side thereof opposite said base and in continuous electrical contact therewith extending between said end terminations in continuous parallel electrical connection with said high resistance film element said low resistance element having a slope which approximates the minimum slope of said predetermined function said low resistance film being spaced from said path of wiper travel and progressively altering the transverse cross sectional dimension of at least said low resistance film element as a function of desired voltage output value and distance from said end terminations by progressively sensing the voltage output value along said path of wiper travel and altering the transverse cross sectional dimension of said low resistance value responsively thereto by effectively varying the transverse dimension of said low resistance film element on the side thereof remote from said path of wiper travel,
to provide a potentiometer element varying as a function of distance from said end terminations.
7. The method as claimed in claim 6 wherein said predetermined function is non-linear.
8. A potentiometer having a predetermined function comprising an insulating base a longitudinally extended conductive plastic high resistance film element on said base having end terminations on opposite ends thereof,
said high resistance film element providing a path of wiper travel between said end terminations a wiper movable along said path,
a longitudinally extended conductive plastic low resistance film element superimposed on said high resistance film on the side thereof opposite said base and in continuous electrical contact therewith extending between said end terminations in continuous parallel electrical connection with said high resistance film element,
said low resistance film element being spaced from said path of wiper travel and having its edge remote from said path of wiper travel of varying dimension from its edge adjacent said path of wiper travel to provide a varying transverse dimension thereof said high and low resistance elements together providing a voltage output value at said wiper varying as a predetermined function of distance between said end terminations said high resistance film element having a slope which approximates the maximum slope of said predetermined function and said lowresistance film element having a slope which approximates the minimum slope of said predetermined function.

Claims (8)

1. A potentiometer having a predetermined function comprising a longitudinally extended conductive plastic high resistance film element having end terminations on opposite ends thereof, said high resistance film element providing a path of wiper travel between said end terminations a wiper movable along said path a longitudinally extended conductive plastic low resistance film element superimposed on said high resistance film element in continuous electrical contact therewith extending between said end terminations in continuous parallel electrical connection with said high resistance film element, said low resistance film element being spaced from said path of wiper travel and having an edge remote from said path of wiper travel of varying dimension from its opposed edge to provide a varying transverse dimension thereof said high and low resistance film elements together providing a voltage value at said wiper varying as a function of distance between said end terminations.
2. A potentiometer as claimed in claim 1 wherein the edge of said low resistance element adjacent to said path of wiper travel is diffused progressively transversely.
3. A potentiometer as claimed in claim 1 wherein said high resistance element has a slOpe which approximates the maximum slope of said predetermined function and said low resistance element has a slope which approximates the minimum slope of said predetermined function.
4. A potentiometer having a predetermined function comprising an insulating base a longitudinally extended conductive plastic high resistance film element on said base having end terminations on opposite ends thereof, said high resistance film element providing a path of wiper travel between said end terminations a wiper movable along said path, a longitudinally extended conductive plastic low resistance film element superimposed on said high resistance film on the side thereof opposite said base and in continuous electrical contact therewith extending between said end terminations in continuous parallel electrical connection with said high resistance film element, said low resistance film element being spaced from said path of wiper travel and having its edge adjacent said path of wiper travel diffused progressively transversely to increase the resistance value thereof in a transverse direction toward said path of wiper travel and spaced therefrom, the opposite edges of said films remote from said wiper path being of varying dimension from said adjacent edge to provide a varying transverse dimension thereof said high and low resistance elements together providing a voltage output value at said wiper varying as a predetermined function of distance between said end terminations said high resistance film element having a slope which approximates the maximum slope of said predetermined function and said low resistance film element having a slope which approximates the minimum slope of said predetermined function.
5. A potentiometer as claimed in claim 4 wherein said predetermined function is non-linear.
6. The method of making a potentiometer element having a predetermined function comprising the steps of providing an insulating base a longitudinally extended conductive plastic high resistance film element having end terminations on said base said high resistance film element having a maximum voltage output slope that closely approximates the slope of said predetermined function said high resistance film element having a path of wiper travel between said end terminations and a longitudinally extended conductive plastic low resistance film element superimposed on said high resistance film element on the side thereof opposite said base and in continuous electrical contact therewith extending between said end terminations in continuous parallel electrical connection with said high resistance film element said low resistance element having a slope which approximates the minimum slope of said predetermined function said low resistance film being spaced from said path of wiper travel and progressively altering the transverse cross sectional dimension of at least said low resistance film element as a function of desired voltage output value and distance from said end terminations by progressively sensing the voltage output value along said path of wiper travel and altering the transverse cross sectional dimension of said low resistance value responsively thereto by effectively varying the transverse dimension of said low resistance film element on the side thereof remote from said path of wiper travel, to provide a potentiometer element varying as a function of distance from said end terminations.
7. The method as claimed in claim 6 wherein said predetermined function is non-linear.
8. A potentiometer having a predetermined function comprising an insulating base a longitudinally extended conductive plastic high resistance film element on said base having end terminations on opposite ends thereof, said high resistance film element providing a path of wiper travel between said end terminations a wiper movable along said path, a longitudinally extended coNductive plastic low resistance film element superimposed on said high resistance film on the side thereof opposite said base and in continuous electrical contact therewith extending between said end terminations in continuous parallel electrical connection with said high resistance film element, said low resistance film element being spaced from said path of wiper travel and having its edge remote from said path of wiper travel of varying dimension from its edge adjacent said path of wiper travel to provide a varying transverse dimension thereof said high and low resistance elements together providing a voltage output value at said wiper varying as a predetermined function of distance between said end terminations said high resistance film element having a slope which approximates the maximum slope of said predetermined function and said low resistance film element having a slope which approximates the minimum slope of said predetermined function.
US00280809A 1972-08-15 1972-08-15 Electrical resistance element and method of manufacture Expired - Lifetime US3851293A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US00280809A US3851293A (en) 1972-08-15 1972-08-15 Electrical resistance element and method of manufacture

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US00280809A US3851293A (en) 1972-08-15 1972-08-15 Electrical resistance element and method of manufacture

Publications (1)

Publication Number Publication Date
US3851293A true US3851293A (en) 1974-11-26

Family

ID=23074750

Family Applications (1)

Application Number Title Priority Date Filing Date
US00280809A Expired - Lifetime US3851293A (en) 1972-08-15 1972-08-15 Electrical resistance element and method of manufacture

Country Status (1)

Country Link
US (1) US3851293A (en)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4075452A (en) * 1976-06-08 1978-02-21 Societe Francaise De L'electro-Resistance Electroresistor and method of making same
US4100525A (en) * 1976-05-10 1978-07-11 Allen-Bradley Company Single setting variable resistor
US4243969A (en) * 1978-04-18 1981-01-06 Preh, Elektrofeinmechanische Werke Jakob Preh Nachf. Gmbh & Co. Layer resistor element
US4812419A (en) * 1987-04-30 1989-03-14 Hewlett-Packard Company Via connection with thin resistivity layer
US5339065A (en) * 1993-06-10 1994-08-16 Slenker Stephen A Adjustable microelectronic potentiometer

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2759078A (en) * 1951-11-13 1956-08-14 North American Aviation Inc Compensated miniature potentiometer and method of making
US3379567A (en) * 1964-06-12 1968-04-23 Beckman Instruments Inc Tailored variable electrical resistance element

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2759078A (en) * 1951-11-13 1956-08-14 North American Aviation Inc Compensated miniature potentiometer and method of making
US3379567A (en) * 1964-06-12 1968-04-23 Beckman Instruments Inc Tailored variable electrical resistance element

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4100525A (en) * 1976-05-10 1978-07-11 Allen-Bradley Company Single setting variable resistor
US4075452A (en) * 1976-06-08 1978-02-21 Societe Francaise De L'electro-Resistance Electroresistor and method of making same
US4243969A (en) * 1978-04-18 1981-01-06 Preh, Elektrofeinmechanische Werke Jakob Preh Nachf. Gmbh & Co. Layer resistor element
US4812419A (en) * 1987-04-30 1989-03-14 Hewlett-Packard Company Via connection with thin resistivity layer
US5339065A (en) * 1993-06-10 1994-08-16 Slenker Stephen A Adjustable microelectronic potentiometer

Similar Documents

Publication Publication Date Title
US4435691A (en) Dual track resistor element having nonlinear output
US4123741A (en) Resistance element for variable resistors
EP0047849B1 (en) Variable resistance device and a method of making such a device
US4243969A (en) Layer resistor element
EP0018013A1 (en) Strain gauge bridge circuit
WO1981000484A1 (en) Fabrication of film resistor circuits
US2688679A (en) Metallic film variable resistor
DE2516620B2 (en) Process for the manufacture of PIN diodes
DE3779964T2 (en) RESISTIVE TAPE ELEMENT, METHOD FOR PRODUCTION AND USE.
US3851293A (en) Electrical resistance element and method of manufacture
DE3910861A1 (en) ORGANIC PTC THERMISTOR
US4403133A (en) Method of trimming a resistance element
US3393390A (en) Potentiometer resistance device employing conductive plastic and a parallel resistance
US3983528A (en) Resistor network with adjustable resistance value
DE2818706C2 (en) Electrical pressure sensor and pressure measurement method
US3723938A (en) Non-linear potentiometer with conductor array
DE1590768B2 (en) Process for the production of a coherent thin, metal-conductive resistance layer on an isolate the support body
US3473146A (en) Electrical resistor having low resistance values
US2759078A (en) Compensated miniature potentiometer and method of making
US3657692A (en) Trimmer resistor
US3863195A (en) Sliding variable resistor
DE2553385A1 (en) PROCESS FOR MANUFACTURING PRECISE PATTERNS IN THIN METALIZATIONS ON PLASTIC FILM
DE2939477A1 (en) VARIABLE CAPACITOR AND METHOD FOR TRIMMING IT
US3284697A (en) Exponential function potentiometer
US3772631A (en) Resistor and method of making and trimming same