DE8010978U1 - TEMPERATURE DETECTION COMPONENT - Google Patents

Description

HOFFMANN ·. ; ΕΙ; ΤΙ43 <&

PATE N TAN W ALT E DR. ING. E. HOFFMANN (1930-1976). DlPL.-lNG. W.EITLE DR. RER. NAT.K. HOFFMANN DIPL.-ING. W. LEHN

DIPL.-ING. K. FDCHSLE - DR. RER. NAT. B. HANSEN ARABELLASTRASSe-I (STERNHAUS) D-8000 MÖNCHEN 81 TELEPHONE (089) 911087. TELEX 05-29619 (PATHE)

V. Ranco Incorporated, Columbus, Ohio / V.St.v.A.

Temperature sensing component

The invention relates to a temperature sensing component with a capillary filled with filling liquid and a bellows switching head connected to this with a membrane for actuation the switching mechanism of an associated thermostat.

Such temperature detection components are used in cooling, air conditioning and heating technology. The temperature sensing element designed as a capillary is usually in Contact with the medium, the temperature of which is to be recorded. In the case of cooling technology, the capillary is usually on that Evaporator attached to the cooling unit to monitor its temperature.

In the case of known temperature detection components, these are to protect against environmental influences, in particular corrosion, usually with one broken up in a galvanic process

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th plating, preferably provided with a tin plating. Such plating is not in many cases sufficient to prevent corrosion in continuous operation.

In addition to the usual environmental influences, the capillary, especially in cooling technology, be exposed to the cyclical formation of alternating water and ice. if the surface of the capillary shows microscopic hairline cracks, the expansion can be caused by the cyclical *

occurring ice formation lead to the fact that the hairline cracks lead to the wall of the capillary penetrating breaks, which leads to a loss of filling liquid, which leads to the response to temperature changes due to pressure and / or Volume changes are needed. This in turn leads to the fact that the temperature detection component becomes unusable and with the thermostat needs to be replaced.

The invention is based on the object of a temperature detection component of the type described at the outset, which provides permanent resistance to the appearance of corrosion and permanent security against damage due to cyclical water and ice formation offers.

This object is achieved according to the invention in that at least the capillary is covered with a thin layer of plastic. The bellows switch head is also advantageous

I covered a thin layer of plastic.

With this formation of the temperature detection component is achieves that this is better against by oxidation and / or | a galvanic potential between the capillary and the evaporator | corrosion caused by the materials.

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The smooth surface layer filling the microscopic hairline cracks prevents cracks from occurring due to the formation of ice.

An additional covering of the visible parts of the capillary with a plastic tube, as is the case with refrigerators is common in the household, is not applicable.

Finally, the plastic layer is capable of deforming the capillary when it is wound or unwound as a result of its plasticity better to withstand without affecting the properties of the membrane in the bellows switch head.

The plastic layer expediently consists of polyester or made of epoxy resin. It advantageously has a thickness in the range from 20 µm to 70 µm. Such a thickness of the plastic layer ensures that this is not damaged during normal installation of the temperature detection component.

The capillary is advantageously made of copper, whereby both sufficient thermal conductivity and sufficient The elasticity of the capillary is ensured.

The capillary is expediently soldered to the bellows switching head or to this with a binding agent. attached, the thin Plastic layer is applied after soldering or fastening.

An embodiment of the temperature detection component according to the invention is shown in the drawing by "will described in more detail below. Show in the drawing

1 shows a temperature detection component in perspective Representation, and

Pig. 2 shows the bellows switch head of the component according to FIG. 1 in Bottom view.

The temperature detection component shown in the drawing consists of a capillary 1 made of copper tube and one with the capillary 1 liquid-tight connected bellows switch head 2. The connection of the capillary 1 with the bellows switch head 2 at point 3 is expediently made by soldering. At its free end 4, the capillary 1 is after filling with filling liquid sealed liquid-tight. A pinch point 5 also helps to close the capillary 1.

The capillary 1 and the bellows switching head 2 are covered with a thin plastic layer with a thickness in the range of 20 µm to 70 µm coated. The plastic layer is made advantageously made of polyester or epoxy resin.

The plastic layer results in perfect protection against corrosion, in particular of the capillary 1, without the properties of the bellows switch head 2 or the actuating membrane of the bellows switch head 2 are influenced / grounded.

To apply the plastic layer, the entire temperature detection component is expediently heated to around 170C and then immersed in a plastic powder bed made of a powder of polyester or epoxy resin. One Another possibility for applying the plastic layer is to use such powder in an electrostatic way Apply process and then heat the temperature sensing part to about 170 ° C. So you get the desired plastic coating with a smooth surface and uniform thickness, with any hairline cracks being filled and subsequent ice formation no longer has any possibility of generating breaks, in particular of the capillary 1.

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The plastic layer can adapt to the rest

Components of the system or to achieve an identification f

function codes have different colors. It acts as an isola-i'i

gate to avoid potential differences between the ·: '■

Capillary 1 and evaporator materials in the case of installation |

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of the capillary in cooling systems. |

Claims (1)

Temperature sensing component (T protection claims: I 1. Temperature detection component with a with I filling liquid filled capillary and one with this I connected bellows switch head with membrane for operating the I switching mechanism of an associated thermostat, thereby % marked that at least the capillary St (1) is covered with a thin layer of plastic, I 2. temperature detection component according to claim 1, I characterized in that the ball I switch head (2) covered with a thin layer of plastic 3. Temperature sensing component according to claim 1 or 2, characterized in that the Plastic layer consists of polyester. . ■. ■ 4. Temperature sensing component according to claim 1 or 2, characterized in that the Plastic layer consists of epoxy resin. 5. Temperature detection component according to one of the preceding claims, characterized net that the plastic layer has a thickness in the range from 20 µm to 70 µm. (j. Temperature detection component according to one of the preceding claims, characterized in that that the capillary (1) consists of copper. 7. Temperature detection component according to one of the preceding claims, characterized in that that the capillary (1) is soldered to the bellows switch head () or attached to it with a binding agent is.