GB731523A - Improvements in or relating to variable electrical resistances - Google Patents

Improvements in or relating to variable electrical resistances

Info

Publication number
GB731523A
GB731523A GB2449850A GB2449850A GB731523A GB 731523 A GB731523 A GB 731523A GB 2449850 A GB2449850 A GB 2449850A GB 2449850 A GB2449850 A GB 2449850A GB 731523 A GB731523 A GB 731523A
Authority
GB
United Kingdom
Prior art keywords
resistance
conductance
conductances
decade
terminals
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
Application number
GB2449850A
Inventor
Maurice Graham Mcbride
Alan John Crouchman
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.)
Sangamo Weston Ltd
Atos Origin IT Services Inc
Original Assignee
Sangamo Weston Ltd
Sangamo Weston 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 Sangamo Weston Ltd, Sangamo Weston Inc filed Critical Sangamo Weston Ltd
Priority to GB2449850A priority Critical patent/GB731523A/en
Publication of GB731523A publication Critical patent/GB731523A/en
Expired legal-status Critical Current

Links

Classifications

    • GPHYSICS
    • G01MEASURING; TESTING
    • G01RMEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R1/00Details of instruments or arrangements of the types included in groups G01R5/00 - G01R13/00 and G01R31/00
    • G01R1/20Modifications of basic electric elements for use in electric measuring instruments; Structural combinations of such elements with such instruments
    • G01R1/203Resistors used for electric measuring, e.g. decade resistors standards, resistors for comparators, series resistors, shunts

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Measurement Of Resistance Or Impedance (AREA)

Abstract

731,523. Measuring temperature; variable resistance and conductance networks; electric analogue calculating systems. SANGAMO WESTON, Ltd. July 5. 1951 [Oct. 6, 1950], No. 24498/50. Class 37. [Also in Group XXXVIII] .Relates to resistance and conductance networks adjustable in steps so as to simulate a non-linear law of the type Rt=Ro (1+-at-bt<2>) between a variable t and the 'resistance R. The invention is based or derived in accordance with the principle that the resistance/temperature curve of a resistance whose value varies uniformly with temperature t shunted by a resistance of constant value approximates to the required curve. According to a first aspect (Figs. 1 and 2), the invention provides a resistance network comprising two terminals (T1, T2) and two resistances (R1-R3) and (R4) connected in parallel with respect to said terminals and at least two control means (e.g. switches S3 and S4) calibrated respectively in terms of a different unit of said variable for varying a first one of said resistances (R3) in linear manner and at least one of said calibrated control means (S4) simultaneously varying the second one of said resistances (R4) in a non- linear manner. In Fig. 2 the switch S3 controlling the R3 or hundreds decade is ganged to switch S4 of step shunt resistor R4 so that a different value of shunt is switched in across the series three-decade combination R3, R2, R1 at each adjustment position of switch S3. Fig. 2 is calibrated for measurements from - 100‹ to +500‹ C. The negative values are measured by setting S3, S4 on the negative step (shown ringed) corresponding to - 100‹ C. and in effect operating S1, S2 in reverse against negative indices shown individually ringed in Fig. 1, e.g. - 100‹ C. is given by the S3 setting on the ringed negative in R3 with S2 at - 90‹ C. (or zero on the positive range) in R2 and S1 at - 10‹ C..(or zero on the positive range) in R1. According to a second aspect the invention provides a resistance or conductance network comprising two terminals (T1, T2), Fig. 3, two resistances or conductances (X and Y-X) connected between said terminals such that the resistance (R) or conductance between the said terminals is expressible in the form X(Y - X)/Y and calibrated control means (S1 and S2) for varying in a non-linear manner the total resistance or conductance in the manner that the resistance or conductance X is varied in a linear manner whilst maintaining constant the total resistance or conductance Y. In Fig. 4 the closed loop Y is translated into series resistors R4-R8 with R4, R5 in 10‹ and 100‹ C. steps respectively. The X100 switch S2 may be connected to junction x between R7/R8 with x chosen such that R7=R6 minus the total resistance of R4 so as to provide a - 100‹ C. setting. A further arrangement, Fig. 5, has the closed loop Y comprising decade boxes B1, B2 with similar denominations coupled so that B1 adds/subtracts as B2 subtracts/adds respectively and in equal increments. In Fig. 6, B is a decade resistance as described above and at bridge balance B indicates directly the temperature of the platinum resistance thermometer Rt. Fig. 7 is a conversion into conductances with B now C (conductance) in an opposite arm and using conductances it is shown that at balance (see Fig. 8) Rt=X(Y - X)/Y, where Rt represents a platinum resistance thermometer and conductance arm C comprises conductances X/K and Y-X/K in series (K=PQ). Conductances are switched in parallel for addition and to maintain Y constant while X varies a conductance is switched from shunting X to shunting Y-X. This is demonstrated in Fig. 9 wherein biriary-counting relays operate on change-over switches RS1-RS7 so that C1- C7 shunt Cx or Cy. Figs. 10 and 11 (not shown), illustrate decade-conductance networks with the total conductance Y held constant by step or bar switching controlling the required conductances. The invention is fully developed and explained mathematically throughout the Specification. The arrangements disclosed may be employed in a multi-range bridge type temperature indicator or recorder wherein the lowest step resistance or conductance comprises a motor-driven self-balance slide wire. Further temperature measuring applications consist in controlling the switches by a stepping mechanism provided with a cyclometer dial indicator or coupling the switches to printing heads for chart printing in time sequence.
GB2449850A 1950-10-06 1950-10-06 Improvements in or relating to variable electrical resistances Expired GB731523A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
GB2449850A GB731523A (en) 1950-10-06 1950-10-06 Improvements in or relating to variable electrical resistances

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB2449850A GB731523A (en) 1950-10-06 1950-10-06 Improvements in or relating to variable electrical resistances

Publications (1)

Publication Number Publication Date
GB731523A true GB731523A (en) 1955-06-08

Family

ID=10212596

Family Applications (1)

Application Number Title Priority Date Filing Date
GB2449850A Expired GB731523A (en) 1950-10-06 1950-10-06 Improvements in or relating to variable electrical resistances

Country Status (1)

Country Link
GB (1) GB731523A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP3786599A1 (en) * 2019-09-02 2021-03-03 ContiTech Schlauch GmbH Measuring device for detecting temperature-dependent resistance changes and hose system comprising such a measuring device
CN113470489A (en) * 2021-05-21 2021-10-01 淮北师范大学信息学院 Network type bridge resistance measurement experiment instrument and operation method

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP3786599A1 (en) * 2019-09-02 2021-03-03 ContiTech Schlauch GmbH Measuring device for detecting temperature-dependent resistance changes and hose system comprising such a measuring device
CN113470489A (en) * 2021-05-21 2021-10-01 淮北师范大学信息学院 Network type bridge resistance measurement experiment instrument and operation method

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