CN101839872B - Device and method for detecting bimetallic thermo-sensitive property - Google Patents

Abstract

The invention discloses a device and a method for detecting bimetallic thermo-sensitive property. The device comprises a torsion measuring device, a temperature control oil tank arranged below the torsion measuring device and an electronic contact indicator connected with the torsion measuring device, wherein the torsion measuring device comprises a bracket platform, a sample holding rod (bracket) arranged on the bracket platform and submerged in the temperature control oil tank and a measuring pen capable of moving on the bracket platform; and the measuring pen comprises a micrometer head and a measuring rod which is connected with the micrometer head by a connecting block and submerged in the temperature control oil tank and contacts a sample. According to the device and the method for detecting the bimetallic thermo-sensitive property, the 'specific thermal deflection value' of a thermal bimetallic sample at the temperature of between 20 and 300 DEG C can be measured, and the maximal measurement deviation does not exceed +/- 1.0 percent, which meets precision requirements of national standard GB/T8364-1987 'Test Method for Specific Thermal Deflection of thermostat Metals'.

Description

A kind of bimetallic thermo-sensitive property pick-up unit and detection method thereof

The present invention relates to a kind of pick-up unit and detection method thereof of metal material physical property, particularly, the present invention relates to a kind of pick-up unit and the detection method thereof of bimetallic thermo-sensitive property that be used to measure than bending.

Background technology

The thermo bimetal is by the constituent element layer of different expansion coefficient (two-layer, or more than two-layer) metal (or alloy), along entire contact surface strong bonded and the compound substance that forms each other.

Because the thermal expansivity difference of each constituent element layer and the internal stress skewness in thermo bimetal cross section, when thermo bimetal's temperature variation (as: during heating), the curvature of this compound substance will change, and produce distortion.When distortion is restricted, then carry out energy exchange, thermal power transfer is become mechanical energy, produce displacement and thrust, make material have the specific function of " power " and " displacement ".

The thermo bimetal is called heat sensitivity because of temperature variation produces crooked characteristic.

By different component shapes, thermo bimetal's flexure operation has variety of ways such as straight line and rotation.It can produce certain thrust and can do work in motion.The size of size, mode of motion and the generation thrust of curved transition amount depended on factors such as the difference of thermal expansion coefficient of constituent element layer material, height, component shape size, elastic modulus and the thickness of temperature compare after the thermo bimetal was heated.

Heat sensitivity is to weigh the important indicator of thermo bimetal to the responsive to temperature degree, also is one of topmost performance of thermo bimetal.Thermo bimetal's " than crooked " is the tolerance of expression temperature and heat sensitivity, is the most basic, the topmost characterisitic parameter that characterizes in the characteristic that bends with temperature variation.For this reason, be widely used in the characterisitic parameter of the thermal sensing element in temperature indication, temperature control, temperature compensation and the various automatic control equipment than the function of bending.

At present, the instrument that does not have ready-made complete detection bimetallic thermo-sensitive property on the market.

Along with special steel branch office to thermo bimetal's Products Development and application, how to provide a kind of equipment that can detect thermo bimetal's product thermo-sensitive property be the puzzlement those skilled in the art a difficult problem.

Summary of the invention

For addressing the above problem; The objective of the invention is to: a kind of pick-up unit that is used to measure bimetallic thermo-sensitive property is provided; The pick-up unit of said measurement bimetallic thermo-sensitive property can be measured " than the bending value " of the thermo bimetal's sample in 20～300 ℃ of scopes; Its maximum measured deviation is no more than ± and 1.0%, meet the accuracy requirement in GB/T8364-1987 " thermo bimetal is than the bend test method " national standard.

Pick-up unit according to measurement bimetallic thermo-sensitive property of the present invention; It is simple that this device has a device structure; Sample is easy to fix, and is easy to operate, and measuring accuracy is high, measuring repeatability is good; And, solved the technical barrier that detects thermo bimetal's product thermo-sensitive property with advantages such as actual user mode are similar.Satisfied all kinds of thermo bimetals than bending property detection demand.

Bimetallic thermo-sensitive property pick-up unit of the present invention; Comprise surveying and scratch device, place and survey the temperature control fuel tank of scratching the device below, scratch the electronics contact pointer that device is connected with survey; It is characterized in that; Said survey is scratched device and is comprised: rack platform, be arranged on the rack platform, not the sample holder bar in the temperature control fuel tank and the measuring pen that can on rack platform, move, said measuring pen comprises sounding rod, the sounding rod upper end is micrometer head, is connected with micrometer head through contiguous block; The sounding rod lower end and contacts with the sample contact not in the temperature control fuel tank.

According to bimetallic thermo-sensitive property pick-up unit of the present invention; It is characterized in that; Said measuring pen can move on rack platform through the mobile slideway at rack platform top; On the surface plate at rack platform top, design the leader, be fixed on and move on the slideway, can move above-mentioned survey easily thus and scratch device.

According to bimetallic thermo-sensitive property pick-up unit of the present invention; It is characterized in that said sounding rod is a metal bar, the metal bar of its cross sectional dimensions and micrometer head protrusion is measure-alike; Be with the upper and lower part metal sleeve on it; Be formed with a step on the inwall in said metal sleeve, between the bottom, between above-mentioned step and lower metal sleeve pipe, be provided with spring, this step plays the effect of buckle to the spring of its underpart; Upper sleeve is positioned at base top, is enclosed within the outside of spring, is used to adjust the upper-lower position of sounding rod, following parts casing pipe be positioned at run through base portion and and base, i.e. temperature control fuel tank top plate fixed connection, pointed contact is formed at said sounding rod bottom.

According to bimetallic thermo-sensitive property pick-up unit of the present invention, it is characterized in that, but said upper sleeve 10A inside diameter D 2 to be slightly larger than the diameter D1 of step with making loose fit; But the inside diameter D 3 of following parts casing pipe 10B is slightly less than D2 to be slightly larger than sounding rod diameter D with making loose fit.

According to bimetallic thermo-sensitive property pick-up unit of the present invention; It is characterized in that; But spring inside diameter D4 to be slightly larger than sounding rod diameter D with making loose fit; Play buckle effect and less than the diameter D1 of step, but spring D outer diameter 5 is slightly larger than D3 to make loose fit ground, play card only effect and be slightly larger than down the diameter D3 of parts casing pipe 10B.

According to bimetallic thermo-sensitive property pick-up unit of the present invention, it is characterized in that, the sounding rod of said measuring pen, sleeve pipe, the sample holder bar is to process with the low-expansion alloy material.

A kind of detection method of measuring bimetallic thermo-sensitive property of the present invention is used bimetallic thermo-sensitive property pick-up unit recited above, with thermometal sample to be measured not in room temperature T ₁The oil of temperature control fuel tank in, on the sample low bulk course, an end inserts surveys the sample patchhole of scratching device sample holder bar bottom, another free end is free straight bar state; Two power supply contact heads of electronics contact pointer communicate with measuring pen, sample holder bar respectively, make electronics contact pointer, measuring pen, sample, sample holder bar form a loop; The micrometer head on a wheel measuring top; The sounding rod that makes the measuring pen bottom is to extending below; Revolve when the tip of the sounding rod that has micrometer head and to extend the moment that contacts with the sample free end surface; Send signal by the high sensitive electronic contact pointer, the flexural deformation reading value f1 (mm) of record thermo bimetal's sample this moment; The oily temperature of temperature control fuel tank is heated to high temperature T2 (100～300 ℃); The micrometer head on a wheel measuring top when the moment that the tip of sounding rod contacts with specimen surface, sends signal by the high sensitive electronic contact pointer, the flexural deformation reading value f2 of record thermo bimetal's sample this moment; According to reading value f ₁, f ₂, T ₁, T ₂And than the computing formula of crooked K, calculate this thermo bimetal's sample than crooked K value.

Computing formula than crooked K is following:

$K=\frac{\mathrm{\&Delta;f}\&times;\mathrm{\&delta;}}{{\mathrm{<figure-callout\; id="2"\; label="L"\; filenames="H200910047973XE00011.png"\; state="\{\{state\}\}">L</figure-callout>}}^2+\mathrm{\&Delta;}{\mathrm{<figure-callout\; id="2"\; label="f"\; filenames="H200910047973XE00011.png"\; state="\{\{state\}\}">f</figure-callout>}}^2+\mathrm{\&Delta;f}\&times;\mathrm{\&delta;}}\&times;\frac{1}{T_2-{\mathrm{<figure-callout\; id="1"\; label="T"\; filenames="H200910047973XE00011.png"\; state="\{\{state\}\}">T</figure-callout>}}_1}$

In the formula: K---than crooked, (10 ^-6/ ℃)

Δ f---the measurement temperature is T ₁And T ₂The time sample free-ended amount of deflection poor, (mm)

L---measurement point is promptly measured length, (mm) to the air line distance of bare terminal end

δ---sample thickness, (mm)

T ₁---measure initial temperature, (℃)

T ₂---measure finishing temperature, (℃).

According to bimetallic thermo-sensitive property detection method of the present invention, it is characterized in that reading value f ₁, f ₂In (0～25) mm scope.

Detection method according to measurement bimetallic thermo-sensitive property of the present invention; It is characterized in that an end of sample stretches into to survey and scratches in the holding frame of device, is fixed by fishbolt; On the sample low bulk course, and clamp sample according to the required power value of sample with torque spanner.

Adopt cantilever method measure the thermo bimetal than bending property K value:

As room temperature T ₁During measurement, an end of sample stretches into to survey and scratches in the holding frame of device, is fixed by fishbolt; On the sample low bulk course; And clamp sample according to the required power value of sample with torque spanner, and another free end is free straight bar state, and contiguous block closely contacts sounding rod with set nut with micrometer head; Move slideway and slideway set nut and adjust and fix the measurement extension position of sample; Extend the moment that contacts with the sample free end surface when revolving the tip that has the sounding rod of micrometer head, send signal, the reading f of record micrometer head this moment by the high sensitive electronic contact pointer ₁

Carry out high temperature T then ₂Measure, scratch device to the survey that sample is housed and put into the exact constant temperature oil groove, connect the heating of exact constant temperature oil groove; Adjust exact constant temperature oil groove temperature control instrument then; After exact constant temperature oil groove temperature control instrument reflection arrives required measurement temperature, turn micrometer head, the moment that contacts with specimen surface when the tip of sounding rod; Send signal by the high sensitive electronic contact pointer, the reading f of record micrometer head this moment ₂, calculate than crooked K value by sag Δ f and temperature Δ T then.

The thermo bimetal is than the computing formula of crooked K:

$K=\frac{\mathrm{\&Delta;f}\&times;\mathrm{\&delta;}}{{\mathrm{<figure-callout\; id="2"\; label="L"\; filenames="H200910047973XE00011.png"\; state="\{\{state\}\}">L</figure-callout>}}^2+\mathrm{\&Delta;}{\mathrm{<figure-callout\; id="2"\; label="f"\; filenames="H200910047973XE00011.png"\; state="\{\{state\}\}">f</figure-callout>}}^2+\mathrm{\&Delta;f}\&times;\mathrm{\&delta;}}\&times;\frac{1}{T_2-{\mathrm{<figure-callout\; id="1"\; label="T"\; filenames="H200910047973XE00011.png"\; state="\{\{state\}\}">T</figure-callout>}}_1}$

In the formula: K---than crooked, (10 ^-6/ ℃)

Δ f---the measurement temperature is T ₁And T ₂The time sample free-ended amount of deflection poor, (mm)

L---measurement point is promptly measured length, (mm) to the air line distance of bare terminal end

δ---sample thickness, (mm)

T ₁---measure initial temperature, (℃)

T ₂---measure finishing temperature, (℃)

Measuring principle than bending: cantilever method is measured the thermo bimetal than bending property, is to adopt to fix sample one end, and the other end is free, in certain temperature range, measures the relation of its curvature and temperature variation, compares bending value through calculating it.

Than crooked measuring method: the sample that will the measure thickness clamper of packing into, sample one end is fixed, the other end is free straight bar state.Regulate measurement point and clamper distance L, then sample is placed in the thermostatic oil bath.According to the temperature of required measurement, measure sag Δ f and temperature Δ T with respect to moving length, by formula calculate then than crooked K value.

Detection method according to measurement bimetallic thermo-sensitive property of the present invention is characterized in that, reading value f ₁, f ₂In (0～25) mm scope.

Detection method according to measurement bimetallic thermo-sensitive property of the present invention is characterized in that, high temperature T ₂In (100～300) ℃ scope.

Detection method according to measurement bimetallic thermo-sensitive property of the present invention is characterized in that, an end of sample stretches into to survey and scratches in the holding frame of device, is fixed by fishbolt, on the sample low bulk course, and clamps sample with torque spanner according to the required power value of sample.

Detection method according to measurement bimetallic thermo-sensitive property of the present invention is characterized in that, sample and contact position, the pointed contact sounding rod bottom are pre-formed a recessed contact point.

According to the present invention; A kind of pick-up unit and detection method thereof that is used to measure bimetallic thermo-sensitive property is provided; Can measure " than the bending value " of the thermo bimetal's sample in 20～300 ℃ of scopes; Its maximum measured deviation is no more than ± and 1.0%, meet the accuracy requirement in GB/T8364-1987 " thermo bimetal is than the bend test method " national standard.

Pick-up unit and detection method thereof according to measurement bimetallic thermo-sensitive property of the present invention; It is simple that this device has a device structure; Sample is easy to fix, and is easy to operate, and measuring accuracy is high, measuring repeatability is good; And, solved the technical barrier that detects thermo bimetal's product thermo-sensitive property with advantages such as actual user mode are similar.Satisfied all kinds of thermo bimetals than bending property detection demand.

The simple declaration of accompanying drawing

Fig. 1 is that the present invention surveys the structural representation of scratching device.

Fig. 2 is that the present invention of Fig. 1 surveys the vertical view of scratching device.

Fig. 3 is that the present invention surveys the amplification view of scratching device sounding rod part.

Among the figure, 1 is to survey to scratch device, and 2 for placing survey to scratch the temperature control fuel tank of device below, and 3 for to scratch the electronics contact pointer that device is connected with survey; 4 is rack platform, 5 for be arranged on the rack platform, the sample holder bar (frame) in the temperature control fuel tank not, 6 is the measuring pen that can on rack platform, move, 7 is micrometer head; 8 be through contiguous block be connected with micrometer head, not in the temperature control fuel tank, and the sounding rod that contacts with sample, 9 is pointed contact, sounding rod lower end, 10A, B are respectively the top and the bottom sleeve pipe; 11 is set nut, and 12 is contiguous block, and 13 is spring; 14 is sample, and 15 is handle, and 16 for moving slideway.

D is the sounding rod diameter, and D1 is a stepped diameters, and D2, D3 are respectively the internal diameter of upper sleeve 10A and following parts casing pipe 10B, and D4, D5 are respectively spring inside diameter and external diameter.

Embodiment

Below, lift embodiment, specify a kind of pick-up unit and the detection method thereof that is used to measure bimetallic thermo-sensitive property of the present invention.

Embodiment 1-48:

A kind of bimetallic thermo-sensitive property pick-up unit comprises surveying and scratches device 1, place and survey the temperature control fuel tank 2 of scratching the device below, scratch the electronics contact pointer 3 that device is connected with survey.Said survey is scratched device and is comprised: rack platform 4, be arranged on the rack platform, not the sample holder bar (frame) 5 in temperature control fuel tank 2 and the measuring pen 6 that can on rack platform, move; Said measuring pen comprise micrometer head 7, through contiguous block 12 be connected with micrometer head 7, not in temperature control fuel tank 2, and the sounding rod 8 that contacts with sample.

Said measuring pen can move on rack platform through the mobile slideway at rack platform top, and design leader 16 on the surface plate at rack platform top is fixed on and moves on the slideway, can move above-mentioned survey easily thus and scratch device.

Said sounding rod; The metal bar of its cross sectional dimensions and micrometer head protrusion is measure-alike; Be with the upper and lower part metal sleeve on it; Be formed with a step on the inwall in said metal sleeve, between the bottom, between above-mentioned step and lower metal sleeve pipe, be provided with spring, this step plays the effect of buckle to the spring of its underpart.

Upper sleeve is positioned at base top, is enclosed within the outside of spring, is used to adjust the upper-lower position of sounding rod, following parts casing pipe be positioned at run through base portion and and base, i.e. temperature control fuel tank top plate fixed connection, pointed contact is formed at said sounding rod bottom.

But said upper sleeve 10A inside diameter D 2 to be slightly larger than the diameter D1 of step with making loose fit; But the inside diameter D 3 of following parts casing pipe 10B is slightly less than D2 to be slightly larger than sounding rod diameter D with making loose fit.

But spring inside diameter D4 is slightly larger than sounding rod diameter D to make loose fit ground, play buckle effect and less than the diameter D1 of step, but spring D outer diameter 5 to be slightly larger than D3 with making loose fit, play card only effect and be slightly larger than down the diameter D3 of parts casing pipe 10B.

The sounding rod of said measuring pen, top and the bottom sleeve pipe (10A, B), the sample holder bar is with 4J36 low bulk invar alloy material.Said micrometer head is for measuring the micrometer callipers of 0.001mm.

The top of said rack platform is a surface plate made of insulating material, and said measuring pen can move on rack platform through the mobile slideway at rack platform top.Design leader 16 is fixing on the surface plate at rack platform top, or is fixed on mobile slideway, can move the survey that fuses easily and scratch device.

In the present embodiment, said contiguous block 12 is metal sleeves, is enclosed within the top of the metal bar and the sounding rod of micrometer head bottom, and micrometer head, sounding rod are fused.

The work of bimetallic thermo-sensitive property pick-up unit is following:

The inspection entire equipment makes equipment in shape: input voltage 220V ± 5% before measuring.Energized is opened the exact constant temperature oil groove.

With sample alignment gently, remove the surface oxidation look of surperficial foul and sample and sounding rod contact site before measuring.Sample one end is packed in the holding frame, clamp sample, make on the sample low bulk course, and keep straight horizontality.Press the sample testing length requirement, adjustment sounding rod to sample holder frame stiff end distance.Sample and contact position, the pointed contact sounding rod bottom are pre-formed a recessed contact point.

Clamp sample with torque spanner, high sensitivity trade mark holding force is 30kg, and moderate degree trade mark holding force is 40kg, puts into the exact constant temperature oil groove to sample gently then.

After treating ambient-temp-stable, the room temperature T that shows on the record exact constant temperature oil groove temperature control instrument ₁, turn micrometer head then, the moment that contacts with specimen surface when the tip of sounding rod, the sample free end position f when sending signal during the record room temperature by the high sensitive electronic contact pointer ₁

Temperature required according to measuring, adjustment exact constant temperature bath temperature control instrument is connected exact constant temperature bath heater switch then, connects the stirrer power supply, makes the exact constant temperature oil groove begin to heat up.With 100C ℃/time firing rate, rise to thermometric temperature (150 ℃) from room temperature, be incubated 15～20 minutes then, the measurement temperature T that shows on the record exact constant temperature bath temperature control instrument ₂

Cut off the stirrer power supply, the turn micrometer head when the moment that the tip of sounding rod contacts with specimen surface, when sending signal by the high sensitive electronic contact pointer, writes down the sample free end position f when measuring then ₂

Measure and finish, close oil groove, powered-down.

With the above-mentioned T that records ₁T ₂And f ₁f ₂, calculate than crooked K value by following formula:

Δf＝f ₂-f ₁

$K=\frac{\mathrm{\&Delta;f}-\mathrm{\&delta;}}{T_2-{\mathrm{<figure-callout\; id="1"\; label="T"\; filenames="H200910047973XE00011.png"\; state="\{\{state\}\}">T</figure-callout>}}_1}\&times;\frac{1}{\mathrm{\&Delta;}{\mathrm{<figure-callout\; id="2"\; label="f"\; filenames="H200910047973XE00011.png"\; state="\{\{state\}\}">f</figure-callout>}}^2+{\mathrm{<figure-callout\; id="2"\; label="L"\; filenames="H200910047973XE00011.png"\; state="\{\{state\}\}">L</figure-callout>}}^2}$

In the formula: K: than crooked, 10 ^-6/ ℃

δ: sample thickness, mm

Δ f: the free-ended amount of deflection of sample changes mm

T ₁: the initial measurement temperature of sample, ℃

T ₂: the end of sample is to measuring temperature, ℃

f ₁: be T ₁The time sample free end position, mm

f ₂: be T ₂The time sample free end position, mm.

Measurement result is following:

According to the present invention; A kind of pick-up unit and detection method thereof that is used to measure bimetallic thermo-sensitive property is provided; Can measure " than the bending value " of the thermo bimetal's sample in 20～300 ℃ of scopes; Its maximum measured deviation is no more than ± and 1.0%, meet the accuracy requirement in GB/T8364-1987 " thermo bimetal is than the bend test method " national standard.

Pick-up unit and detection method thereof according to measurement bimetallic thermo-sensitive property of the present invention; It is simple that this device has a device structure; Sample is easy to fix, and is easy to operate, and measuring accuracy is high, measuring repeatability is good; And, solved the technical barrier that detects thermo bimetal's product thermo-sensitive property with advantages such as actual user mode are similar.Satisfied all kinds of thermo bimetals than bending property detection demand.

Claims (9)

1. bimetallic thermo-sensitive property pick-up unit; Comprise surveying and scratch device (1), place and survey the temperature control fuel tank (2) of scratching the device below, scratch the electronics contact pointer (3) that device is connected with survey; It is characterized in that said survey is scratched device and comprised: rack platform (4), be arranged on the rack platform, not the sample holder bar (5) in the temperature control fuel tank and the measuring pen (6) that can on rack platform, move, said measuring pen (6) comprises the micrometer head (7) of sounding rod (8) and sounding rod upper end; Said sounding rod is connected with micrometer head through contiguous block (12); The sounding rod lower end and contacts with sample (14) contact not in the temperature control fuel tank

Said sounding rod is a metal bar; Be with upper and lower part metal sleeve (10A on it; 10B); Be formed with a step on the inwall in said upper metal sleeve pipe, between the bottom, between above-mentioned step and lower metal sleeve pipe, be provided with spring (13), this step plays the effect of buckle to the spring of its underpart; Upper metal sleeve pipe (10A) is positioned at base top, is enclosed within the outside of spring, is used to adjust the upper-lower position of sounding rod, lower metal sleeve pipe (10B) be positioned at run through base portion and with the base fixed connection, pointed contact is formed at said sounding rod bottom.

2. bimetallic thermo-sensitive property pick-up unit as claimed in claim 1; It is characterized in that; Said measuring pen (6) can move on rack platform through the mobile slideway at rack platform (4) top; On the surface plate at rack platform top, design leader (15), be fixed on the mobile slideway (16), can move above-mentioned survey easily thus and scratch device.

3. bimetallic thermo-sensitive property pick-up unit as claimed in claim 1 is characterized in that, said upper metal sleeve pipe (10A) internal diameter (D2) but to be slightly larger than the diameter (D1) of step with making loose fit; The internal diameter (D3) of lower metal sleeve pipe (10B) but to be slightly larger than sounding rod diameter (D), be slightly less than upper metal sleeve pipe (10A) internal diameter (D2) with making loose fit.

4. bimetallic thermo-sensitive property pick-up unit as claimed in claim 1; It is characterized in that; Spring inside diameter (D4) but to be slightly larger than sounding rod diameter (D) with making loose fit; Play buckle effect and less than the diameter (D1) of step, spring external diameter (D5) but with make loose fit and play card only effect and be slightly larger than the diameter (D3) of lower metal sleeve pipe (10B).

5. bimetallic thermo-sensitive property pick-up unit as claimed in claim 1 is characterized in that, the sounding rod of said measuring pen, and metal sleeve, sample holder bar are to process with the low-expansion alloy material.

6. a bimetallic thermo-sensitive property detection method is characterized in that, uses the described bimetallic thermo-sensitive property pick-up unit of claim 1, with thermometal sample to be measured not in room temperature T ₁The oil of temperature control fuel tank in, on the sample low bulk course, an end inserts surveys the sample patchhole of scratching device sample holder bar bottom, another free end is free straight bar state; Two power supply contact heads of electronics contact pointer communicate with measuring pen, sample holder bar respectively, make electronics contact pointer, measuring pen, sample, sample holder bar form a loop; The micrometer head on a wheel measuring top; The sounding rod that makes the measuring pen bottom is to extending below; Revolve when the tip of the sounding rod that has micrometer head and to extend the moment that contacts with the sample free end surface, send signal by the high sensitive electronic contact pointer, the flexural deformation reading value f of record thermo bimetal's sample this moment ₁The oily temperature of temperature control fuel tank is heated to high temperature T ₂100～300 ℃; The micrometer head on a wheel measuring top when the moment that the tip of sounding rod contacts with specimen surface, sends signal by the high sensitive electronic contact pointer, the flexural deformation reading value f of record thermo bimetal's sample this moment ₂According to reading value f ₁, f ₂, T ₁, T ₂And than the computing formula of crooked K, calculate this thermo bimetal's sample than crooked K value,

Computing formula than crooked K is following:

$K=\frac{\mathrm{\&Delta;f}\&times;\mathrm{\&delta;}}{L^2+\mathrm{\&Delta;}{f}^2+\mathrm{\&Delta;f}\&times;\mathrm{\&delta;}}\&times;\frac{1}{T_2-T_1}$

In the formula: K---than crooked, 10 ^-6/ ℃

Δ f---the measurement temperature is T ₁And T ₂The time sample free-ended amount of deflection poor, the mm of unit

L---measurement point is promptly measured length to the air line distance of bare terminal end, the mm of unit

δ---sample thickness, the mm of unit

T ₁---measure initial temperature, ℃

T ₂---measure finishing temperature, ℃.

7. bimetallic thermo-sensitive property detection method as claimed in claim 6 is characterized in that, reading value f ₁, f ₂In 0～25mm scope.

8. bimetallic thermo-sensitive property detection method as claimed in claim 6; It is characterized in that an end of sample stretches into to survey and scratches in the sample holder bar of device, is fixed by fishbolt; On the sample low bulk course, and clamp sample according to the required power value of sample with torque spanner.

9. bimetallic thermo-sensitive property detection method as claimed in claim 6 is characterized in that, sample and contact position, the pointed contact sounding rod bottom are pre-formed a recessed contact point.

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