JP2007248262A - Temperature indicator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a temperature indicator having high temperature detection sensitivity of a measuring object with reduced sliding resistance of a movable member. <P>SOLUTION: This temperature indicator 1 comprises a case 2 mounted on the measuring object, a temperature-responsive member 10 contracting or expanding owing to a temperature change with one end side thereof mounted to within the case 2, a movable member 9 mounted on the other end side of the temperature-responsive member 10 and slidingly displaced in the axial direction of the case 2 owing to the contraction or expansion of the temperature-responsive member 10, a low-temperature indication part 11 mounted on one end side of the movable member 9 and projecting from the case 2 when temperature becomes a prescribed low temperature or lower, and a high-temperature indication part 13 mounted on the other end side of the movable member 9 and projecting from the case 2 when temperature becomes a prescribed high temperature or higher. The movable member 9 is formed out of stainless steel to form a nickel-phosphorus alloy film on its surface by electroless plating and fluororesin is impregnated into the alloy film. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a temperature indicator that is attached to an object to be measured such as a pipe for steam or hot water, a valve or a device for controlling these high-temperature fluids, and displays the temperature level of the object to be measured. Knowing the temperature of piping, valves, and equipment of high-temperature fluid not only helps prevent burns, but also knows the operating state of the valve and the operating state of the equipment. For example, in the case of a steam trap that automatically discharges condensate without escaping steam from the steam piping system, the steam is normal at a medium temperature if it is within a predetermined temperature range, but if it is higher than the predetermined temperature range, It can be inferred that there is a leaking high temperature abnormality, and if the temperature is lower than the predetermined temperature range, it can be inferred that the drainage is insufficient or cannot be drained.

  A conventional temperature indicator includes a case attached to an object to be measured, a temperature responsive member accommodated in the case and contracted or expanded due to a temperature change of the object to be measured, and a temperature responsive member attached to the temperature responsive member. Accordingly, the movable member is slidably displaced in the axial direction of the case, and the display unit is attached to the movable member and protrudes outward from or intrudes into the case.

The conventional temperature indicator has a problem in that the temperature detection sensitivity of the object to be measured is low because the sliding resistance of the movable member is large.
JP-A-2005-300458

  The problem to be solved is to provide a temperature indicator having a high detection sensitivity of the temperature of the object to be measured by reducing the sliding resistance of the movable member.

  The present invention includes a case attached to an object to be measured, a temperature responsive member accommodated in the case and contracted or expanded due to a temperature change of the object to be measured, and a case attached to the temperature responsive member by contraction or extension of the temperature responsive member. A movable member that is slidably displaced in the axial direction, and a display unit that is attached to the movable member and protrudes outwardly or immerses inwardly with respect to the case. A nickel-phosphorus alloy film is formed on the surface of the material by electroless plating, and the nickel-phosphorus alloy film is impregnated with a fluororesin.

  The present invention produces an excellent effect that the temperature detection sensitivity of the object to be measured can be increased by coating the surface of the movable member with a fluororesin to reduce the sliding resistance.

  In the present invention, the movable member is formed of a metal material, a nickel-phosphorus alloy film is formed on the surface of the metal material by an electroless plating method, and the nickel-phosphorus alloy film is impregnated with a fluororesin. That is, since the surface of the movable member of the present invention is coated with a fluororesin, the sliding resistance can be reduced by the low friction coefficient of the fluororesin. Therefore, the temperature indicator of the present invention can increase the temperature detection sensitivity of the object to be measured.

  An embodiment showing a specific example of the above technical means will be described (see FIGS. 1 and 2). The case 2 of the temperature indicator 1 is formed of a left main body 3 and a right main body 4 each having an outer shape of a substantially quadrangular prism and an inner shape, and the right end of the left main body 3 is press-fitted into the left end of the right main body 4. Fix it. The left main body 3 and the right main body 4 are made of aluminum having a high thermal conductivity. Each of the left main body 3 and the right main body 4 may be formed in a polygonal shape such as a substantially triangular shape or a hexagonal shape, or in a cylindrical shape.

  The left main body 3 integrally includes a partition wall 6 having a through hole 5 in the center, and the right main body 4 integrally includes a partition wall 8 having a through hole 7 in the center. A movable member 9 is disposed in the case 2 through the through hole 5 and the through hole 7. The movable member 9 is slidably displaced in the axial direction of the case 2 while being guided by the through hole 5 and the through hole 7. The movable member 9 is made of stainless steel, a nickel-phosphorus alloy film is formed on the surface thereof by an electroless plating method, and the nickel-phosphorus alloy film is impregnated with a fluororesin. One end (right end) side of the temperature-responsive member 10 made of bimetal is welded to the partition wall 8 of the right main body 4. The other end (left end) side of the temperature responsive member 10 is welded and attached to substantially the center of the movable member 9. A low temperature display portion 11 having a U-shaped cross section is attached to one end (right end) side of the movable member 9 with a set screw 12, and a high temperature display portion 13 having a U-shaped cross section is disposed on the other end (left end) side of the movable member 9. Is attached with a set screw 14.

  The bimetal is obtained by firmly bonding two kinds of metals or alloys having different thermal expansion coefficients into a plate shape, and bends in response to a temperature change. A spiral winding made by spirally winding a strip-shaped bimetal flat plate is spirally wound again to form a double spiral winding. In the first spiral shape, the inside is made of a low expansion material and the outside is made of a high expansion material. In the case of this helically wound shape, the radius becomes smaller and the length becomes longer when the temperature is high, and the opposite action occurs when the temperature is low. And in the case of the double helix formed using this, the radius becomes smaller and the length becomes longer when the temperature becomes high, and the opposite action is exerted when the temperature becomes low.

  The temperature indicator 1 is attached to, for example, an adhesive tape 16 on the outer surface of a bimetal steam trap 15 as an object to be measured. The temperature responsive member 10 contracts to displace the movable member 9 when the temperature of the bimetallic steam trap 15 decreases, and expands to displace the movable member 9 to the left when the temperature of the bimetallic steam trap 15 increases. . When the bimetal steam trap 15 operates normally and, for example, condensate below a set temperature of about 65 ° C. to 75 ° C. is automatically discharged, both the low temperature display portion 11 and the high temperature display portion 13 are in the case 2. I'm immersed in it. Thereby, it can confirm that it is normal. When the bimetal steam trap 15 is in a state where drainage is insufficient or cannot be drained and the temperature becomes a predetermined low temperature, for example, 60 ° C. or less, the temperature responsive member 10 contracts and the movable member 9 is displaced to the right. Although it is immersed, the low temperature display part 11 protrudes from the case 2. Thereby, the low temperature abnormality which is a state with insufficient drainage or inability to drain can be confirmed. When the bimetal steam trap 15 leaks condensate or steam at a set temperature or higher and reaches a predetermined high temperature, for example, 80 ° C. or higher, the temperature responsive member 10 expands and the movable member 9 is displaced to the left. Is immersed in the case 2, but the high temperature display portion 13 protrudes from the case 2. Thereby, the high temperature abnormality which the steam is leaking can be confirmed.

Sectional drawing of the temperature indicator of the Example of this invention. The front view which shows the state which attached the temperature indicator of the Example of this invention to the bimetal type steam trap.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Temperature indicator 2 Case 3 Left main body 4 Right main body 5,7 Through-hole 6,8 Bulkhead 9 Movable member 10 Temperature response member 11 Low temperature display part 13 High temperature display part 15 Bimetallic steam trap

Claims (1)

A case attached to the object to be measured, a temperature responsive member housed in the case and contracted or expanded due to a temperature change of the object to be measured, and a case attached to the temperature responsive member in the axial direction of the case by the contraction or expansion of the temperature responsive member A movable member that is slidably displaced and a display unit that is attached to the movable member and that protrudes outward or immerses inwardly with respect to the case. The movable member is made of a metal material, and is formed on the surface of the metal material. A temperature indicator characterized in that a nickel-phosphorus alloy film is formed by an electroless plating method, and the nickel-phosphorus alloy film is impregnated with a fluororesin.

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