CN204065204U

CN204065204U - Double bridge

Info

Publication number: CN204065204U
Application number: CN201420549493.XU
Authority: CN
Inventors: 骆君
Original assignee: Individual
Current assignee: Individual
Priority date: 2014-09-22
Filing date: 2014-09-22
Publication date: 2014-12-31
Anticipated expiration: 2024-09-22

Abstract

A kind of double bridge for measuring small resistor, it has two step discs, a slide wire disc, ratio arms adopts the integral number power resistance value of 10, overcomes current portable direct-flow double bridge ratio arms and adopts non-ten to enter round values, improve the precision manufacturing electric bridge resistance, thus improve electric bridge accuracy, relatively arm have employed slide wire disc, and it can provide two and half readings, adds measured resistance readings figure place.

Description

Double bridge

Technical field

The utility model relates to the instrument measured small resistor.

Background technology

Adopt the portable double bridge of slide wire disc can only increase a step disc again, and ratio arms resistance right and wrong ten enter integer, it is correctly difficult that this just makes portable double bridge ratio do, and valid reading is also few.

Utility model content

The purpose of this utility model, be a kind of double bridge of design, adopt two step discs and a slide wire disc, ratio arms resistance adopts the resistance of the integral number power resistance of ten.

The technical solution of the utility model is taked like this: it has four blade seven throw switch K, the measuring resistance of seven four terminated lines is welded with above four blade seven throw switch K, every measuring resistance four terminals are connected respectively with four layers of normally opened contact on the same gear of four blade seven throw switch K: on × 100 multiplying power four layers of normally opened contact, weld 10K Ω measuring resistance four terminals respectively, × 10 multiplying power four layers of normally opened contact weld 1K Ω measuring resistance four terminals respectively, × 1 multiplying power four layers of normally opened contact weld 100 Ω measuring resistance, four terminals respectively, × 0.1 multiplying power four layers of normally opened contact weld 10 Ω measuring resistance, four terminals respectively, × 0.01 multiplying power four layers of normally opened contact weld 1 Ω measuring resistance, four terminals respectively, × 0.001 multiplying power four layers of normally opened contact weld 0.1 Ω measuring resistance, four terminals respectively, × 0.0001 multiplying power four layers of normally opened contact weld 0.01 Ω measuring resistance, four terminals respectively, the right-hand member of the working power E of electric bridge and the external measured resistance " R of four terminated lines _x" C ₂terminal connects, measured resistance " R _x" P ₂terminal is connected with the outer arm slide wire disc III Metal Contact ring comparing arm, the outer arm slide wire disc III of comparison arm is 0 ~ 1r resistance, relatively the top of the outer arm slide wire disc III of arm i.e. " 0 " contact connects the Metal Contact ring comparing the outer arm measure dish II of arm, measurement dish II has 0, 1, 2, 10 totally 11 gears, the resistance one that resistance is 1r is welded between every two adjacent contacts, relatively " 0 " contact of the outer arm measure dish II of arm connects the Metal Contact ring comparing the outer arm measure dish I of arm, measurement dish I has 0, 1, 2, 10 totally 11 gears, the resistance one that resistance is 10r is welded between every two adjacent contacts, after relatively " 0 " contact of the outer arm measure dish I of arm connects galvanometer diagonal line summit A, be connected with four blade seven throw switch K left side second layer metal contact ring through 100 Ω resistance, measured resistance " R _x" P ₁terminal is connected with the inner arm slide wire disc III ' Metal Contact ring comparing arm, relatively the inner arm slide wire disc III ' of arm is above 0 ~ 1r resistance, relatively the top of the inner arm slide wire disc III ' of arm i.e. " 0 " contact connects the Metal Contact ring comparing the interior arm measure dish II ' of arm, relatively the interior arm measure dish II ' of arm has 0, 1, 2, 10 totally 11 gears, welding resistance between every two adjacent contacts is that " 0 " contact that the resistance one of 1r only compares the interior arm measure dish II ' of arm connects the Metal Contact ring comparing the interior arm measure dish I ' of arm, relatively the interior arm measure dish I ' of arm has 0, 1, 2, 10 totally 11 gears, the resistance one that resistance is 10r is welded between every two adjacent contacts, after relatively " 0 " contact of the interior arm measure dish I ' of arm connects galvanometer diagonal line summit B, be connected with second layer metal contact ring on the right of four blade seven throw switch K through 100 Ω resistance, outer arm measure dish I is the first step disc comparing arm with interior arm measure dish I ', when step disc rotates, interior outer arm is synchronous, the resistance increased or reduce is identical, outer arm measure dish II is the second step disc comparing arm with interior arm measure dish II ', when step disc rotates, interior outer arm is synchronous, the resistance increased or reduce is also identical, in like manner, in slide wire disc, outer arm is synchronous, the left end of the working power E of electric bridge is connected with four blade seven throw switch K left side first layer metal contact ring through 0.4 Ω resistance, measured resistance " R _x" C ₁terminal is connected with first layer metal contact ring on the right of four blade seven throw switch K.

By above technical scheme, owing to having two step discs and a slide wire disc, just add portable double bridge valid reading figure place, ratio arms resistance adopts the integral number power of ten.The ratio of electric bridge is made to do more accurate.

Accompanying drawing explanation

Accompanying drawing is this double bridge basic circuit diagram.

Embodiment

In the drawings, first step disc compares 10 × 10r on the outer arm measure dish I of arm, represent and measurement dish I has 10 resistances to be resistant series of 10r, second step disc compares 10 × 1r on the outer arm measure dish II of arm, represent and measurement dish II has 10 resistances to be resistant series of 1r, in like manner, first step disc compares 10 × 10r on the interior arm measure dish I ' of arm, represent that measurement dish I ' above has 10 resistances to be resistant series of 10r, second step disc compares 10 × 1r on the interior arm measure dish II ' of arm, represent that measurement dish II ' above has 10 resistances to be resistant series of 1r.In the drawings, on step disc, thick black line represents Metal Contact ring, and hollow small circle represents hard contact, and four-headed arrow represents metallic brush.In the drawings, when K switch put × 100 multiplying power gear time, the ratio due to outer arm in the galvanometer left side and 10K Ω measuring resistance equals outer arm and measured resistance R on the right of galvanometer _xratio, if on the right of galvanometer in outer arm resistance be R _l

Then there are 100 Ω/10K Ω=R _l/ R _xr _x=10K Ω/100 Ω × R _lr _x=100 R _l

……

When K switch put × 0.0001 multiplying power gear time, 100 Ω/0.01 Ω=R _l/ R _xr _x=0.0001R _l

The span of resistance r is between 0.005 Ω ~ 500 Ω, and when r gets 0.01 Ω, at × 0.0001 multiplying power gear, the every stepping of the first step disc is 10 micro-ohms, and slide wire disc full scale is 1 micro-ohm, and the every lattice scale of slide wire disc is 0.01 micro-ohm; When r gets 100 Ω, at × 100 multiplying power gears, the every stepping of the first step disc is 100K Ω, and slide wire disc full scale is 10K Ω, and the every lattice scale of slide wire disc is 100 Ω.Therefore, this double bridge can have very Wide measuring range, during specific design, r can be allowed to get different value, name double bridge by different model.

When removing 10K Ω or 0.01 Ω measuring resistance in seven measuring resistances, four blade six throw switch can be adopted to form the double bridge of six ratio multiplying powers, in like manner, remove a measuring resistance again, four blade five throw switch can be adopted to form the double bridge of five ratio multiplying powers, in addition, two 100 Ω resistance of ratio arms inside and outside the galvanometer left side, also 1K Ω can be used instead, at this moment × 100 multiplying powers become × 10 multiplying powers, two 100 Ω resistance of ratio arms inside and outside the galvanometer left side, 10 Ω can also be used instead, at this moment × 10 multiplying powers become × 100 multiplying powers, this also can form a variety of different model name double bridge.

Claims

1. a double bridge, it is characterized in that it has four blade seven throw switch K, the measuring resistance of seven four terminated lines is welded with above four blade seven throw switch K, every measuring resistance four terminals are connected respectively with four layers of normally opened contact on the same gear of four blade seven throw switch K: on × 100 multiplying power four layers of normally opened contact, weld 10K Ω measuring resistance four terminals respectively, × 10 multiplying power four layers of normally opened contact weld 1K Ω measuring resistance four terminals respectively, × 1 multiplying power four layers of normally opened contact weld 100 Ω measuring resistance, four terminals respectively, × 0.1 multiplying power four layers of normally opened contact weld 10 Ω measuring resistance, four terminals respectively, × 0.01 multiplying power four layers of normally opened contact weld 1 Ω measuring resistance, four terminals respectively, × 0.001 multiplying power four layers of normally opened contact weld 0.1 Ω measuring resistance, four terminals respectively, × 0.0001 multiplying power four layers of normally opened contact weld 0.01 Ω measuring resistance, four terminals respectively, the right-hand member of the working power E of electric bridge and the external measured resistance " R of four terminated lines _x" C ₂terminal connects, measured resistance " R _x" P ₂terminal is connected with the outer arm slide wire disc III Metal Contact ring comparing arm, the outer arm slide wire disc III of comparison arm is 0 ~ 1r resistance, relatively the top of the outer arm slide wire disc III of arm i.e. " 0 " contact connects the Metal Contact ring comparing the outer arm measure dish II of arm, measurement dish II has 0, 1, 2, 10 totally 11 gears, the resistance one that resistance is 1r is welded between every two adjacent contacts, relatively " 0 " contact of the outer arm measure dish II of arm connects the Metal Contact ring comparing the outer arm measure dish I of arm, measurement dish I has 0, 1, 2, 10 totally 11 gears, the resistance one that resistance is 10r is welded between every two adjacent contacts, after relatively " 0 " contact of the outer arm measure dish I of arm connects galvanometer diagonal line summit A, be connected with four blade seven throw switch K left side second layer metal contact ring through 100 Ω resistance, measured resistance " R _x" P ₁terminal is connected with the inner arm slide wire disc III ' Metal Contact ring comparing arm, relatively the inner arm slide wire disc III ' of arm is above 0 ~ 1r resistance, relatively the top of the inner arm slide wire disc III ' of arm i.e. " 0 " contact connects the Metal Contact ring comparing the interior arm measure dish II ' of arm, relatively the interior arm measure dish II ' of arm has 0, 1, 2, 10 totally 11 gears, welding resistance between every two adjacent contacts is that " 0 " contact that the resistance one of 1r only compares the interior arm measure dish II ' of arm connects the Metal Contact ring comparing the interior arm measure dish I ' of arm, relatively the interior arm measure dish I ' of arm has 0, 1, 2, 10 totally 11 gears, the resistance one that resistance is 10r is welded between every two adjacent contacts, after relatively " 0 " contact of the interior arm measure dish I ' of arm connects galvanometer diagonal line summit B, be connected with second layer metal contact ring on the right of four blade seven throw switch K through 100 Ω resistance, outer arm measure dish I is the first step disc comparing arm with interior arm measure dish I ', when step disc rotates, interior outer arm is synchronous, the resistance increased or reduce is identical, outer arm measure dish II is the second step disc comparing arm with interior arm measure dish II ', when step disc rotates, interior outer arm is synchronous, the resistance increased or reduce is also identical, in like manner, in slide wire disc, outer arm is synchronous, the left end of the working power E of electric bridge is connected with four blade seven throw switch K left side first layer metal contact ring through 0.4 Ω resistance, measured resistance " R _x" C ₁terminal is connected with first layer metal contact ring on the right of four blade seven throw switch K.

2. double bridge according to claim 1, the span of resistance r is between 0.005 Ω ~ 500 Ω.

3. double bridge according to claim 1 or 2, also can adopt four blade six throw switch, the measuring resistance of six four terminated lines, six ratio multiplying powers, as long as remove 10K Ω or 0.01 Ω measuring resistance; Also four blade five throw switch, the measuring resistance of five four terminated lines, five ratio multiplying powers can be adopted; Four blade four throw switch, the measuring resistance of four four terminated lines, four ratio multiplying powers can also be adopted; Or adopt four blade three throw switch, the measuring resistance of three four terminated lines, three ratio multiplying powers; In addition, inside and outside the galvanometer left side, ratio arms is two 100 Ω resistance, also can use 1K Ω or 10 Ω instead, form multiple ratio;

Therefore, inside and outside the galvanometer left side, ratio arms is two 100 Ω resistance, four blade seven throw switch, and measuring resistance, seven ratio multiplying powers of seven four terminated lines can not limit as to the one of claim 1.