CN201017006Y - Portable potentiometer - Google Patents
Portable potentiometer Download PDFInfo
- Publication number
- CN201017006Y CN201017006Y CNU2007201075871U CN200720107587U CN201017006Y CN 201017006 Y CN201017006 Y CN 201017006Y CN U2007201075871 U CNU2007201075871 U CN U2007201075871U CN 200720107587 U CN200720107587 U CN 200720107587U CN 201017006 Y CN201017006 Y CN 201017006Y
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- CN
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- Prior art keywords
- resistance
- contact
- bracket panel
- measuring disk
- brush
- Prior art date
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Abstract
The utility model is a four-range DC potentiometer, which is provided with three metering plates and is used for DC voltage metering. A fist step plate of the potentiometer consists of a metering plate (21 multiplied by 100 Omega), a non-resistance auxiliary plate I' and a non-resistance auxiliary plate I''. A second step plate consists of a metering plate mainly comprising an annular resistance net (10 multiplied by 10Omega), and an auxiliary plate consisting of 10 resistors (0.5 Omega). A third plate is a double slide-wire plate. One wire is a metering slide wire, while the wire is an auxiliary side wire. Two metering plates and metering slide wires are connected via wires and are not switched via a switch, so no influence of variation or thermal potential happens in metering with the potentiometer. Moreover, replacement plates of the first step plate and the second step plate are omitted.
Description
Technical field
The utility model relates to the instrument that DC voltage is measured.
Background technology
Current for the potential difference meter that three measuring disk are arranged, in the connection between three measuring disk, telophragma generally adopts switch to switch, and so just produces the variation of contact resistance, brings restriction to resolution.In order to overcome this problem, generally adopt big brush with the increase contact area, and adopt silver-carbon/carbon-copper composite material; Patent No. ZL200520101772.0 has announced that the potential difference meter that three measuring disk are arranged solves the variation new method of switch contact resistance, its first, second 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 first step disc was declined at 0 o'clock, the total resistance of circuit changed when second step disc was put different indicating value, first step disc was put at 0 o'clock, the total resistance of circuit was constant when second step disc was put different indicating value, first step disc removes for this reason measuring disk, outside the replacement dish, increased bracket panel distinguish step disc put 0 and the circuit of declining 0 two kinds of situations connect, second 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.Two measuring disk connect the back and are connected two with slide wire disc 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, also just do not produce variation; Because first, second step disc all has the replacement dish, increased the number of plies that first, second step disc switch contains resistance, potential difference meter can run into resistance when debugging and maintenance overproof, if switch nexine resistance is overproof, will take switch correction resistance value apart, this makes troubles to debugging and maintenance.
The utility model content
The purpose of this utility model is a kind of portable potentiometer of design, three measuring disk are arranged, and telophragma does not switch by switch in the connection of three measuring disk, and first, second step disc cancellation replacement dish, make resistance be contained in the switch skin, bring convenience revising resistance value.
The technical solution of the utility model is taked like this: electric current from the positive pole of potential difference meter 1.5V working power through the setting resistance R of the resistance measurement network on two step discs and the two slide wire disc to 509 Ω
NAnd the lockable adjustable resistance R of 0～1 Ω
P2, again to 75 Ω resistance R
0, through 0～125 Ω adjustable resistance R
P1Get back to the negative pole of working power and form potential difference meter work loop; Standard cell E
NAnodal arriving through the double-point double-throw switch K that is connected to galvanometer G between two normally closed contacts set up resistance R
NAnd lockable adjustable resistance R
P2, process 100K Ω current-limiting resistance R is to standard cell E again
NNegative pole is formed the potential difference meter standard loop; Be used to connect measured " U
X" two terminals, anodal terminal is formed potential difference meter measurement loop through the double-point double-throw switch K that is connected to galvanometer G between two normally closed contacts to the negative pole terminal again through the resistor network of two measuring disk and two slide wire discs; First step disc has measuring disk I, it has 0,1,2 ... 22 totally 23 gears, except that between 0,1 contact, directly connecting, connect one of 10 Ω resistance between all the other each grade contacts, other has bracket panel I ' and bracket panel I "; the brush of bracket panel I ' and bracket panel I " brush be connected bracket panel I ' and bracket panel I with lead " 0 contact isolated, all the other contacts connect with lead; The 3rd dish is two slide wire discs, two slip thickness materials are identical, resistance all is 0.5 Ω, wherein one is measurement slip III, another root is auxiliary slip III ', and the index dial of two slide wire discs divides 10 big lattice, and the resistance of every big lattice correspondence is 0.05 Ω, every big lattice divide 10 little lattice, and the brush on two slips of two slide wire discs is with a slice metallic brush sheet; Second step disc is made up of measuring disk II and bracket panel II ', measuring disk II has 0,1,2 ... 10 totally 11 gears have the resistance of 10 10 Ω, the 1st resistance R above 0～9 gear
1One end welds the 2nd resistance R
2One end, resistance R
2The other end welds the 3rd resistance R
3One end ... welding successively, the 9th resistance R
9The other end and the 10th resistance R
10An end tie point be the node A of circuit, the 10th resistance R
10The other end and the 1st resistance R
1The other end and the 3rd dish measure 0 of slip III and be connected, 0 that measures slip III is circuit node B, resistance R
1With resistance R
2Tie point be connected resistance R through 16 Ω resistance with the 1st contact
2With resistance R
3Tie point be connected resistance R through 9 Ω resistance with the 2nd contact
3With resistance R
4Tie point be connected resistance R through 4 Ω resistance with the 3rd contact
4With resistance R
5Tie point be connected resistance R through 1 Ω resistance with the 4th contact
5With resistance R
6Tie point be connected resistance R with the 5th contact
6With resistance R
7Tie point be connected resistance R through 1 Ω resistance with the 6th contact
7With resistance R
8Tie point be connected resistance R through 4 Ω resistance with the 7th contact
8With resistance R
9Tie point be connected resistance R through 9 Ω resistance with the 8th contact
9With resistance R
10Tie point be connected resistance R through 16 Ω resistance with the 9th contact
10With resistance R
9Tie point node A through 1 Ω resistance after to node C, node C is connected with the 10th contact after through 15 Ω resistance, measuring disk II " 0 " contact is connected with Node B through 25 Ω resistance, is the resistance of 10 * 0.5 Ω on the bracket panel II ' of second step disc; Bracket panel II ' the 10th contact is connected with the positive pole of potential difference meter working power, 0 contact of bracket panel II ' connects bracket panel I " 0 contact; the brush of bracket panel II ' connects bracket panel I " other contacts except that 0 contact, the brush of measuring disk II connects the brush and bracket panel I of bracket panel I ' after through 195 Ω resistance " the tie point that is connected of brush; bracket panel I ' other contacts except that 0 contact connect measuring disk I the 22nd contact; measuring disk I the 0th; 1 contact is connected with node C; 0 contact of bracket panel I ' is connected the 10th connection setting of measurement slip III resistance R after through 220 Ω resistance with Node B
NNoble potential one end; Two of potential difference meters are measured terminal, and positive pole is connected with measuring disk I brush, are connected with auxiliary slip III ' behind the negative pole process double-point double-throw switch K.
By above technical scheme, first step disc need not the replacement dish, does not all have resistance on the two-layer bracket panel, can be contained in the switch nexine, and measuring disk I is contained in the switch skin; Second step disc need not the replacement dish, 15 ° of angles are rotated in each stepping of switch, and each 11 contact of the bracket panel II ' of second step disc and measuring disk II are distributed in same one deck of switch, and resistance is contained in the switch skin, unload when resistance is overproof and load onto easily, this brings convenience for debugging and maintenance; Make potential difference meter simple in structure like this, volume-diminished has also reduced production cost; On the total circuit partly in potential difference meter internal measurement loop and work loop, there is not switch, so there is not variation influence, when three measuring disk resets of potential difference meter, the potential difference meter working current converges at the B point, in measuring the loop, do not exist working current to flow through lead resistance, the zero potential of potential difference meter is only produced by B point current potential, so this potential difference meter zero potential is very little; Two slide wire resistance thickness materials are identical, and the thermoelectrical potential equal and opposite in direction of generation, direction are opposite, so this potential difference meter thermoelectrical potential is also very little.
Description of drawings
Accompanying drawing is the utility model schematic circuit.
Embodiment
Among the figure, measuring disk II has ten the 10 end to end resistance rings of Ω between 1～9 contact, when measuring disk II puts " 5 ", the brush of measuring disk II is to being that 5 10 Ω resistance are in parallel with 5 10 Ω resistance between the Node B, back in parallel resistance maximum, be 25 Ω, so corresponding point directly are connected on 5 contacts and the resistance ring, resistance all connects into 25 Ω and is as the criterion between all the other contacts of measuring disk II and the Node B; When measuring disk II put " 4 " or puts " 6 ", the brush of measuring disk II was to being that 4 10 Ω resistance are in parallel with 6 10 Ω resistance between the Node B, and back in parallel resistance is 24 Ω, so 4,6 contacts are connected with corresponding point on the resistance ring through 1 Ω resistance; When measuring disk II put " 3 " or puts " 7 ", the brush of measuring disk II was to being that 3 10 Ω resistance are in parallel with 7 10 Ω resistance between the Node B, and back in parallel resistance is 21 Ω, so 3,7 contacts are connected with corresponding point on the resistance ring through 4 Ω resistance; When measuring disk II put " 2 " or puts " 8 ", the brush of measuring disk II was to being that 2 10 Ω resistance are in parallel with 8 10 Ω resistance between the Node B, and back in parallel resistance is 16 Ω, so 2,8 contacts are connected with corresponding point on the resistance ring through 9 Ω resistance; When measuring disk II set or when putting " 9 ", the brush of measuring disk II is to being that 1 10 Ω resistance is in parallel with 9 10 Ω resistance between the Node B, and back in parallel resistance is 9 Ω, so 1,9 contacts are connected with corresponding point on the resistance ring through 16 Ω resistance; When measuring disk II reset, the brush of measuring disk II is to being that 25 Ω resistance connect between the Node B, and when measuring disk II puts " 10 ", the brush of measuring disk II is to being that 16 Ω resistance add 9 Ω resistance rings and connect into 25 Ω resistance between the Node B.
The first step disc reset, second step disc are put " n " (n=0,1,2,3 ... 9,10) time, the brush of bracket panel I ' is that two resistance that are both 220 Ω are in parallel with resistance value between the Node B, is 110 Ω therefore.
First step disc is put " n " (n=0,1,2,3 ... 22), during the second step disc reset, the brush of bracket panel I ' is that two resistance that are both 220 Ω are in parallel with resistance value between the Node B, is 110 Ω therefore.
When first, second step disc during not reset, the brush of bracket panel I ' and the calculating of the resistance value between the Node B except that second step disc is put " 9,10 ", all need to carry out triangle-star conversion.
During the second step disc set, the calculating of resistance value between the brush of bracket panel I ' and the Node B: establish resistance (R
2+ R
3+ ... + R
9) and resistance R
10The both sides resistance is equivalent to resistance r
1, resistance R
10With resistance R
1The both sides resistance is equivalent to resistance r
1' resistance (R
2+ R
3+ ... + R
9) and resistance R
1The both sides resistance is equivalent to resistance r
1", be equivalent to resistance r
1, r
1', r
1" intersection point is Q
1:
R then
1=(R
2+ R
3+ ... + R
9) * R
10/ (R
1+ R
2+ ... + R
10)=80 * 10/100 Ω=8 Ω
r
1’＝R
1×R
10/(R
1+R
2+…+R
10)＝10×10/10×10Ω＝1Ω
r
1”＝(R
2+R
3+…+R
9)×R
1/(R
1+R
2+…+R
10)＝80×10/100Ω＝8Ω
Resistance value equals (211 Ω+r between the brush of bracket panel I ' and the Node B
1) * (211 Ω+r
1")/(2 * 219) Ω+r
1'=219 Ω/2+1 Ω=109.5 Ω+1 Ω=110.5 Ω
When second step disc is put " 2 ", the calculating of resistance value between the brush of bracket panel I ' and the Node B: establish resistance (R
3+ R
4+ ... + R
9) and resistance R
10The both sides resistance is equivalent to resistance r
2, resistance R
10With resistance (R
1+ R
2) the both sides resistance is equivalent to resistance r
2' resistance (R
3+ R
4+ ... + R
9) and resistance (R
1+ R
2) the both sides resistance is equivalent to resistance r
2", be equivalent to resistance r
2, r
2', r
2" intersection point is Q
2:
R then
2=7 Ω r
2'=2 Ω r
2"=14 Ω
Resistance value equals (211 Ω+r between the brush of bracket panel II ' and the Node B
2) * (195 Ω+9 Ω+r
2")/(2 * 218) Ω+r
2'=218 Ω/2+2 Ω=109 Ω+2 Ω=111 Ω.
In like manner, when second step disc was put " 3 ", resistance value was 111.5 Ω between the brush of bracket panel I ' and the Node B,
When second step disc was put " 4 ", resistance value was 112 Ω between the brush of bracket panel I ' and the Node B,
When second step disc was put " 5 ", resistance value was 112.5 Ω between the brush of bracket panel I ' and the Node B,
……
When second step disc was put " 9 ", resistance value was (211/2+9) Ω=114.5 Ω between the brush of bracket panel I ' and the Node B
When second step disc was put " 10 ", resistance value was (210/2+10) Ω=115 Ω between the brush of bracket panel I ' and the Node B.
Because the every stepping of measuring disk II increases by 0.5 Ω, so the every stepping of bracket panel II ' reduces by 0.5 Ω, makes the total resistance of circuit constant.
When the first or second step disc reset, the brush of bracket panel I ' and the resistance value between the Node B are 110 Ω, and 10 * 0.5 Ω resistance of bracket panel II ' all enter circuit.
Electric current is 2mA during the standardization of potential difference meter working current, and I is to being equivalent to resistance r for bracket panel I ' brush process measuring disk
n, r
n', r
n" intersection point Q
n(n=1,2,3 ... 9) brush of resistance value and bracket panel I ' is through 195 Ω resistance R
12To intersection point Q
nResistance value equate, so flow through measuring disk I and 195 Ω resistance R
12Electric current respectively be 1mA; When measuring disk II puts " 9 ", 195 Ω resistance R
12Add 16 Ω resistance and equate to the resistance value of node A with measuring disk I to the resistance value of node A, when measuring disk II puts " 10 ", 195 Ω resistance R
12Add 15 Ω resistance and equate with the resistance value of measuring disk I, so flow through measuring disk I and 195 Ω resistance R to the resistance value of node C
12Electric current also respectively be 1mA.
For ten the 10 Ω end to end resistance rings of measuring disk II between 1～9 contact, resistance R during measuring disk II set
1To be all 10 Ω resistance in parallel with 9 resistances, flows through resistance R
10Electric current be 1/10mA, the voltage U between node A and the Node B
AB=1/10 * 10mV=1mV; Resistance (R when measuring disk II puts " 2 "
1+ R
2) to be all 10 Ω resistance in parallel with 8 resistances, flows through resistance R
10Electric current be 2/10mA, the voltage U between node A and the Node B
AB=2/10 * 10mV=2mV; (n=1,2,3 when in like manner, measuring disk II puts " n " ... 9) voltage U between resistance nodes A and the Node B
AB=nmV; Measuring disk II puts 10 " time, voltage U on the 9 Ω resistance between node A and the Node B
AB=9mV adds 1 Ω resistance R
11Last 1mV, 10mV altogether; When measuring disk I and measuring disk II reset, electric current is without resistance R
10, U
AB=0mV; The electric current that flows through measuring disk I when not reset of measuring disk I is superimposed upon on the measuring disk II at 10 mV voltages between node C, the B, replaces the resistance between 0,1 contact, and during the working current standardization, first step disc is put n
1, second step disc puts n
2, the 3rd dish puts n
3(n
3Represent big lattice indicating value) " U at this moment
x" two measure that voltage is between terminal:
U
x＝1×10n
1+1×n
2/10×10+2×0.05n
3 (mV)
＝10n
1+n
2+0.1n
3 (mV)
The electromotive force of every series-produced standard cell disperses, and between 1.0188V～1.0196V, standardized working current is 2mA, therefore sets up resistance R
NGet 509 Ω, add the lockable adjustable resistance R of 0～1 Ω
P2, variation range that can the coverage criteria cell emf.
Electromotive force was about 1.65V when dry cell was new, and to 1.4V when following, the electric current shakiness can both make the working current of potential difference meter be adjusted to standardization in order to make dry cell under new, former affection condition, for this reason resistance R with old
0Get 75 Ω.Get adjustable resistance R
P1Be 0～125 Ω.
Normalized current is to determine like this: 200mV standard signal voltage is pressed polarity and potential difference meter " U
X" two measure terminal and connect, potential difference meter coils respectively that total indicating value is identical with the standard signal magnitude of voltage, double-point double-throw switch K throws to the left side, adjusting adjustable resistance R
P1, make galvanometer G nulling; Again double-point double-throw switch K is thrown to the right, regulate adjustable resistance R
P2, make galvanometer G nulling, at this moment adjustable resistance R
P2Locking; When using from now on, potential difference meter is standard according to this.
Claims (1)
- A kind of portable potentiometer, electric current from the positive pole of potential difference meter 1.5V working power through the setting resistance R of the resistance measurement network on two step discs and the two slide wire disc to 509 Ω NAnd the lockable adjustable resistance R of 0～1 Ω P2, again to 75 Ω resistance R 0, through 0～125 Ω adjustable resistance R P1Get back to the negative pole of working power and form potential difference meter work loop; Standard cell E NAnodal arriving through the double-point double-throw switch K that is connected to galvanometer G between two normally closed contacts set up resistance R NAnd lockable adjustable resistance R P2, process 100K Ω current-limiting resistance R is to standard cell E again NNegative pole is formed the potential difference meter standard loop; Be used to connect measured " U X" two terminals, anodal terminal is formed potential difference meter measurement loop through the double-point double-throw switch K that is connected to galvanometer G between two normally closed contacts to the negative pole terminal again through the resistor network of two measuring disk and two slide wire discs; It is characterized in that first step disc has measuring disk I, it has 0,1,2 ... 22 totally 23 gears, except that between 0,1 contact, directly connecting, connect one of 10 Ω resistance between all the other each grade contacts, other has bracket panel I ' and bracket panel I "; the brush of bracket panel I ' and bracket panel I " brush be connected bracket panel I ' and bracket panel I with lead " 0 contact isolated, all the other all contacts connect with lead; The 3rd dish is two slide wire discs, two slip thickness materials are identical, resistance all is 0.5 Ω, wherein one is measurement slip III, another root is auxiliary slip III ', and the index dial of two slide wire discs divides 10 big lattice, and the resistance of every big lattice correspondence is 0.05 Ω, every big lattice divide 10 little lattice, and the brush on two slips of two slide wire discs is with a slice metallic brush sheet; Second step disc is made up of measuring disk II and bracket panel II ', measuring disk II has 0,1,2 ... 10 totally 11 gears have the resistance of 10 10 Ω, the 1st resistance R above 0～9 gear 1One end welds the 2nd resistance R 2One end, resistance R 2The other end welds the 3rd resistance R 3One end ... welding successively, the 9th resistance R 9The other end and the 10th resistance R 10An end tie point be the node A of circuit, the 10th resistance R 10The other end and the 1st resistance R 1The other end and the 3rd dish measure 0 of slip III and be connected, 0 that measures slip III is circuit node B, resistance R 1With resistance R 2Tie point be connected resistance R through 16 Ω resistance with the 1st contact 2With resistance R 3Tie point be connected resistance R through 9 Ω resistance with the 2nd contact 3With resistance R 4Tie point be connected resistance R through 4 Ω resistance with the 3rd contact 4With resistance R 5Tie point be connected resistance R through 1 Ω resistance with the 4th contact 5With resistance R 6Tie point be connected resistance R with the 5th contact 6With resistance R 7Tie point be connected resistance R through 1 Ω resistance with the 6th contact 7With resistance R 8Tie point be connected resistance R through 4 Ω resistance with the 7th contact 8With resistance R 9Tie point be connected resistance R through 9 Ω resistance with the 8th contact 9With resistance R 10Tie point be connected resistance R through 16 Ω resistance with the 9th contact 10With resistance R 9Tie point node A through 1 Ω resistance after to node C, node C is connected with the 10th contact after through 15 Ω resistance, measuring disk II " 0 " contact is connected with Node B through 25 Ω resistance, is the resistance of 10 * 0.5 Ω on the bracket panel II ' of second step disc; Bracket panel II ' the 10th contact is connected with the positive pole of potential difference meter working power, 0 contact of bracket panel II ' connects bracket panel I " 0 contact; the brush of bracket panel II ' connects bracket panel I " other contacts except that 0 contact, the brush of measuring disk II connects the brush and bracket panel I of bracket panel I ' after through 195 Ω resistance " the tie point that is connected of brush; bracket panel I ' other contacts except that 0 contact connect measuring disk I the 22nd contact; measuring disk I the 0th; 1 contact is connected with node C; 0 contact of bracket panel I ' is connected the 10th connection setting of measurement slip III resistance R after through 220 Ω resistance with Node B NNoble potential one end; Be used to connect measured " U X" two measure terminals, anodally be connected with measuring disk I brush, negative pole is connected with auxiliary slip III ' after passing through double-point double-throw switch K.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNU2007201075871U CN201017006Y (en) | 2007-04-03 | 2007-04-03 | Portable potentiometer |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNU2007201075871U CN201017006Y (en) | 2007-04-03 | 2007-04-03 | Portable potentiometer |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN201017006Y true CN201017006Y (en) | 2008-02-06 |
Family
ID=39057501
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNU2007201075871U Expired - Fee Related CN201017006Y (en) | 2007-04-03 | 2007-04-03 | Portable potentiometer |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN201017006Y (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100557450C (en) * | 2007-04-03 | 2009-11-04 | 李顺定 | Portable potentiometer |
-
2007
- 2007-04-03 CN CNU2007201075871U patent/CN201017006Y/en not_active Expired - Fee Related
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100557450C (en) * | 2007-04-03 | 2009-11-04 | 李顺定 | Portable potentiometer |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| C19 | Lapse of patent right due to non-payment of the annual fee | ||
| CF01 | Termination of patent right due to non-payment of annual fee |