CN101788588B

CN101788588B - Potentiometer

Info

Publication number: CN101788588B
Application number: CN2009102590816A
Authority: CN
Inventors: 骆晓英
Original assignee: Individual
Current assignee: Individual
Priority date: 2008-08-28
Filing date: 2008-08-28
Publication date: 2011-09-07
Anticipated expiration: 2028-08-28
Also published as: CN101788588A

Abstract

The invention discloses a potentiometer used for measuring direct current voltage, which is provided with three stepping disks and a dual-sliding line disk; each disk forms a measuring disk and a replacing disk by resistors with the same resistance; the three measuring disks and sliding lines of one measuring disk are connected directly by conducting wires without switching by using a switch; and the potentiometer does not have variation and thermoelectric potential effects during measurement.

Description

A kind of single range adopts the DC potentiometer of slide wire disc

Technical field

The present invention relates to instrument that DC voltage is measured.

Background technology

Application number 200510062356.9 has been announced the DC potentiometer that three step discs and two slide wire discs are arranged, its second, the 3rd step disc respectively has measuring disk, replacement dish and bracket panel are formed, measuring disk is identical with resistance on the replacement dish, resistance of the every increase of measuring disk, the replacement dish just reduces same resistance, because second step disc is declined when the 0th contact, the total resistance of circuit changed when the 3rd step disc was put different indicating value, second step disc is put when the 0th contact, it is constant that the 3rd step disc is put the total resistance of different indicating value circuit, second step disc removes for this reason measuring disk, outside the replacement dish, increase bracket panel and distinguished the circuit connection that second step disc is put the 0th contact and declined the two kinds of situations in the 0th contact, the 3rd step disc has also increased bracket panel, has 10 resistance to insert or cut out several resistance respectively above and makes the total resistance of circuit constant.Three measuring disk and a measuring disk slip are connected two and measure between terminals, brush on the step disc switch is got rid of measured outside the loop, do not exist switch to switch between the resistance on three measuring disk and the measuring disk slip, also just do not produce variation; The thermoelectrical potential that has also solved switch with contact variable thermoelectric potential influence.

Because second, third step disc all has bracket panel, increased the number of plies of second, third step disc switch, thereby increased the volume of instrument, also make switch and apparatus structure become complicated, if find in the instrument verification process that particularly second, third step disc measurement data is overproof, the internal layer resistance that revise second, third step disc switch bothers very much.

Summary of the invention

The objective of the invention is to design a kind of DC potentiometer that three measuring disk and two slide wire discs are arranged, contact resistance and variation that its measuring switch stepping is switched, the switch thermoelectrical potential does not influence measurement result; And three step discs and two slide wire discs are all without bracket panel.

Technical scheme of the present invention is taked like this: DC potentiometer comprises that electric current sets up resistance R N and range of adjustment adjustable resistance R at 0～2 Ω through the resistor network on three step discs, the two slide wire disc to 926 Ω from the positive pole of DC potentiometer 4.5V working power _P3, again to 960 Ω fixed resistance R ₀, through the adjustable resistance R of 0～35 Ω _P2And the adjustable resistance R of 22 30 Ω resistance compositions _P1The negative pole of getting back to working power is formed the work loop of DC potentiometer; , arrive and set up resistance R N and lockable adjustable resistance R through being connected to the double-point double-throw switch K of galvanometer G between two normally closed contacts from standard cell EN positive pole _P3, arrive the standard loop that the standard cell negative pole is formed DC potentiometer again; DC potentiometer is used to connect measured " U _X" two terminals, behind the resistor network of anodal terminal, form the equalizing network of DC potentiometer again to the negative pole terminal through the double-point double-throw switch K that is connected to galvanometer G between two normally closed contacts through three measuring disk, a measuring disk slip; It is characterized in that first step disc is that I measuring disk and the I ' replacement dish that 1000/11sts Ω resistance are formed formed by 20 resistances are respectively arranged, second step disc is made up of each II measuring disk and the II ' replacement dish of being made up of 10 11 Ω resistance, and the brush of the brush of measuring disk and replacement dish is through 22 Ω resistance R on second step disc ₂Connect, the 3rd step disc is made up of each III measuring disk and the III ' replacement dish of being made up of 10 11 Ω resistance, the brush of measuring disk is connected through lead with the brush of replacement dish on the 3rd step disc, the 4th dish is two slide wire discs, two slide wire resistance Standard resistance ranges of this pair slide wire disc all are 0～10 Ω, be that top is 0 Ω, end is 10 Ω, wherein one is IV measuring disk slip, another root is an IV ' replacement dish slip, the index dial of two slide wire discs indicates 0,1,2,10 big lattice of 100 one indicating value points, every big lattice are not marked numeral equally distributed 10 little lattice, the corresponding resistance of every big lattice is 1 Ω, " 0 " indicating value of two slide wire disc index dials, dish slip of the IV ' replacement just and IV measuring disk slip the 0th contact, top on the i.e. brush of the two slide wire discs contact slide wire resistance, the index dial of two slide wire discs " 10 " indicating value, dish slip of the IV ' replacement just and IV measuring disk slip the 10th contact, i.e. end on the brush of the two slide wire discs contact slide wire resistance; Brush on two slide wire resistances is with a slice sheet metal; The I ' replacement dish brush connects DC potentiometer working power positive pole, the I ' replacement is coiled the 20th contact and is connected the II ' replacement and coil the 10th contact, the II ' replacement is coiled the 0th contact and is connected the III ' replacement and coil the 10th contact, III measuring disk the 0th contact connects II measuring disk the 10th contact, the resistance R that II measuring disk the 0th contact is 1901/11sts Ω through a resistance ₁The back is connected with I measuring disk the 0th contact, and it is 213200/11sts Ω resistance R through a resistance that the 0th contact is coiled in the I ' replacement ₃The back is connected with the IV ' replacement dish slip the 0th contact, and IV measuring disk slip the 10th contact is connected with I measuring disk the 20th contact; I measuring disk brush connects sets up resistance R N hot end; DC potentiometer is used to connect measured " U _X" two terminals, anodal terminal connects III measuring disk the 10th contact, the negative pole terminal is connected with IV measuring disk slip the 0th contact after through the double-point double-throw switch K that is connected to galvanometer G between two normally closed contacts.

By above technical scheme, three step discs and two slide wire discs are all without bracket panel, and this makes DC potentiometer simple in structure, and volume-diminished, whole instrument overall dimensions reduce many, have also reduced production cost; The measuring disk that instrument is used for measure portion connects with lead, contact resistance and variation be not in equalizing network, the just DC potentiometer work loop of influence always hinders, because total resistance resistance is very big, so variation can be ignored, the thermoelectric potential influence of several μ V be supply voltage, therefore influence can be ignored, zero potential can increase between I measuring disk and the right measuring disk lead resistance greatly to be revised, and the zero potential I increases between I measuring disk and the left side measuring disk lead resistance and revises.

Description of drawings

Fig. 1 is a kind of schematic circuit of the present invention.

In Fig. 1,22 * 30 Ω adjustable resistances resistance R _P1, expression adjustable resistance resistance R _P1Hindered by 22 30 Ω resistance, in like manner, it is that 1000/11sts Ω resistance are formed that 20 * 1000/11 Ω represent by 20 resistances, and 10 * 11 Ω represent to be made up of 10 11 Ω resistance.

Embodiment

In Fig. 1, when two slide wire discs of three step discs and all during reset, left side resistance value equals 2121 Ω between two brushes of first step disc, the right resistance value equals 21210 Ω, therefore, between two brushes of first step disc flow in 10/11 left side of total current, flows in 1/11 the right.When the two slide wire discs of three step discs and were put other contact, the resistance that measuring disk increases in each step disc equaled the resistance that the replacement dish reduces, so left and right limit resistance value is constant between two brushes of first step disc.

DC potentiometer standard operation electric current is 1.1mA, left side electric current 1mA between two brushes of first step disc, the right electric current 0.1mA, left side electric current is divided into two branch roads after flowing to the contact that contacts with the II ' replacement dish brush, and one the tunnel through the II ' replacement dish brush, resistance 22 Ω resistance R ₂, to the contact that contact with II measuring disk brush, this roadlock value is 22 Ω, the contact that contacts with II measuring disk brush is arrived after through two slide wire discs in another road, this roadlock value is 220 Ω, therefore, 22 Ω resistance R ₂On electric current be 10/11mA, the electric current on two slide wire discs is 1/11mA.

After the working current standardization, the I measuring disk is put n ₁, the II measuring disk is put n ₂, the III measuring disk is put n ₃, two slide wire discs are put n ₄(n is certain big lattice indicating value), K switch is thrown to the left side, is positioned at this moment that voltage is between two terminals of measurement:

U _X＝1/11×11n ₃+1/11×110+10/11×11n ₂+1×R ₁+1×1000n ₁/11-0.1×(20-n ₁)×1000/11-0.1×(10-n ₄)×1(mV)

＝n ₃+10+10n ₂+1901/11+1000n ₁/11-2000/11+100n ₁/11-1+0.1n ₄ (mV)

＝1000n ₁/11+100n ₁/11+10n ₂+n ₃+0.1n ₄+10+1901/11-2000/11-1 (mV)

＝100n ₁+10n ₂+n ₃+0.1n ₄ (mV)

The DC potentiometer operating voltage is 1.5V, because the every joint stable electrical of dry cell kinetic potential between 1.4V～1.65V, all can be adjusted to standard state to the DC potentiometer working current for realizing supply voltage at 4.2V～4.95V, gets fixed resistance R ₀=960 Ω, adjustable resistance R _P1=22 * 30 Ω, adjustable resistance R _P2Range of adjustment is between 0～35 Ω.

Internal attachment standard is calibration like this: at " U _x" two of two ends measure terminals and connect 2V normal voltage signal by polarity, K switch is thrown to the left side, the measuring disk indicating value is identical with standard voltage value, by regulating working current adjusting resistance R _P1And R _P2, make the galvanometer nulling, again K switch to be thrown to the right, the electromotive force of unsaturated standard cell disperses when dispatching from the factory in factory, and between 1.0188～1.0196V, sampling is 926 Ω with the resistance of setting up resistance R N, and 0～2 Ω adjustable resistance R has connected _P3, regulate adjustable resistance R _P3, make galvanometer nulling once more, again K switch is thrown to the left side, regulate adjustable resistance R _P2, make the galvanometer nulling, again K switch is thrown to the right, regulate adjustable resistance R _P3, make the galvanometer nulling, when K switch is thrown to the left side and thrown to the right and do not regulate, during the equal nulling of galvanometer, the working current standardization of DC potentiometer is described, promptly sets up ohmically pressure drop and equate, at this moment with adjustable resistance R with the electromotive force of unsaturated standard cell EN _P3Locking, this DC potentiometer is from now on just as standard.

Claims

1. a single range adopts the DC potentiometer of slide wire disc, and it comprises that electric current sets up resistance R N and range of adjustment adjustable resistance R at 0～2 Ω through the resistor network on three step discs, the two slide wire disc to 926 Ω from the positive pole of DC potentiometer 4.5V working power _P3, again to 960 Ω fixed resistance R ₀, through the adjustable resistance R of 0～35 Ω _P2And the adjustable resistance R of 22 30 Ω resistance compositions _P1The negative pole of getting back to working power is formed the work loop of DC potentiometer; , arrive and set up resistance R N and lockable adjustable resistance R through being connected to the double-point double-throw switch K of galvanometer G between two normally closed contacts from standard cell EN positive pole _P3, arrive the standard loop that the standard cell negative pole is formed DC potentiometer again; DC potentiometer is used to connect measured " U _X" two terminals, behind the resistor network of anodal terminal, form the equalizing network of DC potentiometer again to the negative pole terminal through the double-point double-throw switch K that is connected to galvanometer G between two normally closed contacts through three measuring disk, a measuring disk slip; It is characterized in that first step disc is that I measuring disk and the I ' replacement dish that 1000/11sts Ω resistance are formed formed by 20 resistances are respectively arranged, second step disc is made up of each II measuring disk and the II ' replacement dish of being made up of 10 11 Ω resistance, and the brush of the brush of measuring disk and replacement dish is through 22 Ω resistance R on second step disc ₂Connect, the 3rd step disc is made up of each III measuring disk and the III ' replacement dish of being made up of 10 11 Ω resistance, the brush of measuring disk is connected through lead with the brush of replacement dish on the 3rd step disc, the 4th dish is two slide wire discs, two slide wire resistance Standard resistance ranges of this pair slide wire disc all are 0～10 Ω, be that top is 0 Ω, end is 10 Ω, wherein one is IV measuring disk slip, another root is an IV ' replacement dish slip, the index dial of two slide wire discs indicates 0,1,2,10 big lattice of 100 one indicating value points, every big lattice are not marked numeral equally distributed 10 little lattice, the corresponding resistance of every big lattice is 1 Ω, " 0 " indicating value of two slide wire disc index dials, dish slip of the IV ' replacement just and IV measuring disk slip the 0th contact, top on the i.e. brush of the two slide wire discs contact slide wire resistance, the index dial of two slide wire discs " 10 " indicating value, dish slip of the IV ' replacement just and IV measuring disk slip the 10th contact, i.e. end on the brush of the two slide wire discs contact slide wire resistance; Brush on two slide wire resistances is with a slice sheet metal; The I ' replacement dish brush connects DC potentiometer working power positive pole, the I ' replacement is coiled the 20th contact and is connected the II ' replacement and coil the 10th contact, the II ' replacement is coiled the 0th contact and is connected the III ' replacement and coil the 10th contact, III measuring disk the 0th contact connects II measuring disk the 10th contact, the resistance R that II measuring disk the 0th contact is 1901/11sts Ω through a resistance ₁The back is connected with I measuring disk the 0th contact, and it is 213200/11sts Ω resistance R through a resistance that the 0th contact is coiled in the I ' replacement ₃The back is connected with the IV ' replacement dish slip the 0th contact, and IV measuring disk slip the 10th contact is connected with I measuring disk the 20th contact; I measuring disk brush connects sets up resistance R N hot end; DC potentiometer is used to connect measured " U _X" two terminals, anodal terminal connects III measuring disk the 10th contact, the negative pole terminal is connected with IV measuring disk slip the 0th contact after through the double-point double-throw switch K that is connected to galvanometer G between two normally closed contacts.