BG1486U1 - A temperature sensor for monitoring internal combustion engines exhaust gases - Google Patents

Abstract

The useful model is related to a temperature sensor for monitoring ICE exhaust gases, which is applied in the automobile production. The sensor includes a partially perforated body (1) with housed inside vibration damping element (2), and the engaged with it sensitive element (3), which is placed inside the situated in the body (1) supporting filling (5) that envelops the sensitive element (3). In the zone where is placed the sensitive element (3) in the body (1) are formed through openings (4) for extruding the filling (5), and improving the work characteristics, which filling (5) is an alloyed paraffin-based thermoplastic with melting point above 100 Co, and ASTM D3236 viscosity 500-1000 mPa.s at 120 Co.

Description

Technical field

The utility model refers to a temperature sensor for monitoring exhaust gas with application in the automotive industry.

BACKGROUND OF THE INVENTION

JP 2010071735 (A) discloses a temperature sensor comprising a housing and a thermosensitive element, with a filler comprising aluminum oxide as a major component placed between the housing and this element. The housing is made of alloyed Ni, including aluminum.

From JP 2010032237 (A), a temperature sensor is known with excellent vibration resistance, electrical insulation characteristics and temperature measurement accuracy. The sensor includes a thermocouple installed in a protective housing of ceramic compositions, such as aluminum oxide. The injection molded ceramic housing includes: a constant thickness base; a beveled part that is connected to the base and gradually becomes thinner to the outer end, which is the thinnest part of the base. A flange is provided near the boundary between the base and the beveled part. The thermocouple includes copper and copper alloy wires, a glass nozzle and a connecting part. The glass nozzle is fixed to the outer edge of the ceramic protective housing by a filler made primarily of silicone resin (SiO <SB> 2 <J SB>).

The known solutions described above, although achieving a stable attachment of the sensing element inside the housing in order to increase its vibration and shock resistance, do not ensure that the effect of the filler after mounting the sensor in the measuring medium on its measurement characteristics is eliminated.

The technical essence of a useful modep

Accordingly, the purpose of the utility model is to provide a temperature sensor for monitoring the exhaust gas of the ICE, which provides increased strength of the sensing element and, at the same time, has improved measurement characteristics.

The objective was achieved by the creation of a temperature sensor for the monitoring of the exhaust gas of the ICE, comprising a partially perforated housing with a vibration extinguishing element housed therein and a sensing element attached thereto, which is contained in a filling, enclosed in the housing and enclosing the sensing element. The sensor is characterized by the passage openings in the housing area of the sensing element in the extrusion of the filler and improvement of performance, which is an alloyed paraffin-based thermoplastic having a melting point above 100 ° C and a viscosity according to ASTM D3236 500 -1000 mPa.s at 120 ° C.

It is appropriate that the doped paraffinbased thermoplastic be a mixture of C ₁₇ -C ₃₆ alkanes with a long unbranched chain and a narrow dispersion of molecular weight, wholly obtained by Fischer-Trops gas synthesis, including 0.5-5% aliphatic waxes, which increase the melting point of stabilizers and B .

Also suitable for inclusion in the mixture is a translucent, linear, thermoplastic block copolymer based on styrene 30% ethylene butylene in 12-18% by weight.

In a preferred embodiment, the mixture further includes:

Content of oil not more than, wt. % <0.1;

Phosphorus BDS 9779: 1984, mg.kg-1 <1.00 Chlorine, BDS 15172: 1984, mg.kg-1 <0.01 Sulphates, BDS 6941: 1980, mg.kg-1 1.29 Lead, EN 237: 2007, mg.kg -1 <1.00

In addition to the base, butylated hydroxytoluene in 3% by weight is included.

The benefits of the utility model are expressed in ensuring the mechanical strength of the sensor during transport and installation, while maintaining the high accuracy of measuring the exhaust gas temperature, thanks to the special composition of the filler, which evaporates in the first seconds of operation of the sensor.

Explanation of the attached figure

Figure 1 is a schematic representation of the design of the temperature sensor for monitoring the exhaust gas of the ICE.

1486 Ul

Examples of implementation of the utility model

The utility model includes (Fig. 1) a housing 1 in which a vibration damping element 2 is placed, to which a sensitive element 3 is attached. In the housing 1 in the area of the arrangement of the sensitive element 3, apertures are formed

4 used for extrusion of a support filler

5, as well as to improve the functionality of the sensor. The backing 5 is specifically designed for this application and is a paraffin-based thermoplastic alloy that meets the following basic requirements:

1. To increase the resistance of the sensor to shock forces, in particular the metal-ceramic sensing element.

2. Have a minimal, unobtrusive odor of thermal evaporation - decomposition.

3. To evacuate the fully occupied volume for the aforementioned time when blowing off the exhaust.

The thermoplastic has a melting point above 100 ° C, retaining its properties when transported in container by ship or truck worldwide, and a viscosity according to ASTM D3236 500-1000 mPa.s at 120 ° C; allowing its extrusion in a liquid state.

Shelf life must be at least 6 months; to optimize planning and inventory.

The thermoplastic must also have the ability to form stable solutions in the solid and liquid state, be resistant to oxidation and the action of microorganisms for a consistent quality. It must be harmless to humans and the environment, in accordance with current EU standards.

Chemical composition of thermoplastic

The thermoplastic was developed in collaboration with SER Wax Industries, Turin, Italy, and is affixed with the CEP CMP 606.1 trade mark.

The product base is a mixture developed for the application of long branched chain alkanes and a narrow dispersion of molecular weight wholly obtained by Fischer-Trops gas synthesis. A small amount of special aliphatic waxes were added to increase the melting point and UV stabilizers. Two specific additives are also appended to the substrate having a significant effect on the material properties for the application described below.

Base C ₁₇ -C ₃₆

Saturated straight chain hydrocarbons Oil content, mass% <0.1 Phosphorus BDS 9779: 1984, mg.kg-1 <1.00 Chlorine, BDS 15172: 1984, mg.kg-1 <0.01 Sulphates, BDS 6941: 1980, mg.kg -1 1.29 Lead, EN 237: 2007, mg.kg-1 <1.00 Butylated hydroxytoluene (CAS 128-370, E321) was added to the base in 3% wt. This lipophilic phenol is typically used in lubricants, reactive and diesel fuels, suppressing autocatalytic oxidation reactions, by converting peroxy radicals initiating chain reactions to inactive hydroperoxides, by proton donation:

RO2. + BTN -> ROOH + AgO.

RO2. + AgO. -> Products with severely reduced chemical activity

The additive reduces the odor formed mainly by thermal decomposition products - partial oxidation - increases the shelf life of the material and product.

Creighton ^K G1652 is a translucent, linear, thermoplastic block copolymer based on styrene 30% ethylene-butane. Typically used as a modifier in complex mixtures. Its addition in 12-18% wt. increases the viscosity, cohesion and plasto-elasticity, thus the material's resistance to shock loads, as well as the process window of the material in the conditions of mass production. Creighton * G1652 is a trademark of Kraton Performance Polymers Inc. USA

Using the utility model

The support fill 5 (thermoplastic) is placed in the top of the housing 1 of the sensor in the molten state by extrusion through a pressure nozzle. Forced cooling, in order to reduce the production cycle, the filler 5 hardens into a volume formed between the sensitive glass-ceramic element 4 and the perforated housing of the superalloy, thereby providing mechanical support and eliminating the moment available in the case of a paraffin-free sensor.

When fully sensed in an ICE sensor, with the ignition of the latter, the hot exhaust gases evaporate the thermoplastic 5 to the full functionality of the sensor when its measurement characteristics are not affected by the filling due to its physical removal from the measurement area.

Thus protected, the product exhibits a resistance to maximum impact, of the order of more than 180%, at the expense of a single delay in the response time of the sensor lasting less than one minute.

Claims (5)

1. A temperature sensor for monitoring the exhaust gas of an ICE, comprising a partially perforated housing with a vibration extinguishing element housed therein and a sensing element attached thereto; which is housed in a support filling, housed in the housing and enclosing the sensing element, characterized in that through the opening of the sensing element (3) in the housing (1) through holes (4) are formed to extrude the filling (5) , which filler (5) is a doped paraffin-based thermoplastic with a melting point above 100 ° C and a viscosity of 500-1000 mPa.s at 120 ° C. A temperature sensor according to claim 1, characterized in that the alloyed paraffin-based thermoplastic (5) is a mixture of long, unbranched C ₁₇ -C ₃₆ alkanes and a narrow molecular weight dispersion wholly obtained by Fischer-Trops gas synthesis , containing 0.5-5% aliphatic waxes, melting point and UV stabilizers. Temperature sensor according to claim 2, characterized in that it also includes a translucent, linear, thermoplastic block copolymer based on styrene 30% ethylene butane in 12-18% wt. Temperature sensor according to claim 3, characterized in that it further comprises an oil of not more than, wt. % <0.1; phosphorus mg.kg-1 <1.00; chlorine mg.kg-1 0.01; sulfates mg.kg-1 1.29; lead mg.kg-1 <1.00. Temperature sensor according to claim 4, characterized in that it also includes butylated hydroxytoluene in 3% by weight.