FI70454C - ANORDINATION FOR FOERBAETTRANDE AV KALLSTARTEN AV EN FOERBRAENNINGSMOTOR - Google Patents

Description

70454

COLD START IMPROVEMENT DEVICE FOR COMBUSTION ENGINES

The invention relates to a device for improving the cold start of an internal combustion engine, which comprises an oil filter known per se and an electrical resistor 5 placed on its outer surface, which is formed into a wide and thin strip and fastened around the oil filter. This device is especially suitable for use during the cold seasons.

10 It is uncertain whether the car or similar vehicle or implement will start up during the cold seasons after several hours of inactivity. Especially in severe frosts, it is often not possible to start a car that has been standing outside overnight, because the resistance to rotation of the engine is high due to the stiffness of the lubricating oil and the battery charge is reduced by cold, thus reducing the current to the starter motor. This reduces the conditions for starting vehicles with diesel, petrol or similar engines, etc. In addition, cold starting consumes the moot-20 and shortens its service life.

Finnish patent No. 66059 previously discloses a device for improving cold start, in which a conventional oil filter is formed as a heat accumulator by surrounding it with thermal insulation and providing it with one or more electrical resistors for heating or keeping the oil in the filter warm. The electrical resistors are most preferably located on the outer surface of the oil filter. The electrical resistor can be connected to the battery either directly or via a timer. A Ter-30 thermostat has also been used.

The disadvantage of the device described above is in particular that the oil filter is provided with thermal insulation. This thermal insulation must correspond to the dimensions of the oil filter and its wall thickness 35 is, in the most preferred cases, of the order of 2 70454 10 mm. This makes it difficult to install the device because the engine compartment is often cramped and there is not enough space around the filter. Another option is to place a resistor inside the oil filter, but this in turn requires changes to the filter structure.

The object of the invention is e.g. eliminating the above drawbacks and implementing a reliable, yet simple, device that significantly improves the starting of an internal combustion engine in cold even arctic conditions. This is achieved by the features of the invention which are essentially set out in the first claim.

The advantages of the invention over the above-mentioned prior art can be stated as follows. The structure of the device according to the invention is extremely simple; no extra metal parts are needed and the electrical resistor, which is a wide and thin strip, is easy to fasten in place. The most important thing about 20-butter is that the actual thermal insulation is no longer needed. The reason for this is that a large resistance surface is placed against the metal surface of the oil filter, to which most of the thermal energy produced by the electric resistor is due. After all, air is known to be a poor conductor of heat. The device 25 works particularly efficiently when the resistor is placed close to the junction of the oil filter and the engine. In this case, heat is applied to the oil in the filter not only through the metal jacket of the filter directly but also along the metal parts of the base or mounting part of the oil filter to the inner parts of the filter into the filter cartridge itself and thus to the oil in the middle of the filter.

The strip-like resistor is preferably arranged in a single thin layer on the surface of the oil filter. The thickness of the layer is most preferably in the order of a couple of millimeters, so that it can be easily adapted to any oil filter.

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It is also essential for the invention that the strip-like resistor is fixed in place with a thin plastic tape or the like, whereby the thickness of the layer around the filter no longer increases significantly.

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In the following, the invention will be explained in detail with the aid of the accompanying drawing, in which

Fig. 1 schematically shows a pressure lubrication system of an internal combustion engine and Fig. 2 shows an associated oil filter on the outer surface of which an electric resistor is placed.

As is well known, four-stroke engines now have pressure circulation lubrication in common use. This is usually arranged so that the bottom of the crank chamber 1, the so-called oil sump, acts as an oil tank from which the oil is sucked through a strainer 3 into an oil pump 4. The oil is then forced through an oil filter 5 into an oil passage 6 through which it is guided through various oil passages. . The lubrication system of a diesel engine is basically similar.

According to Fig. 2, in connection with the oil filter 5, an electric resistor 7 is mounted on its outer surface so that the thermal power generated therein is transferred as efficiently as possible to the filters 5 and through it to the oil there. The electric resistor 7 is formed as a wide and thin strip and is fastened around the oil filter 5 in connection with this base or fastening part 54 close to the connection point of the oil filter 5 and the motor or the like 30. The electric resistor 7 is formed as a single annular layer and its thickness is most preferably of the order of 1 ... 3 mm.

The electrical resistor 7 comprises spaced-apart resistor-35 wires or a unitary network 8 formed therefrom. Around the resistor network B there is an electrical insulating layer 9 which is a heat-resistant and flexible material such as silicone.

70454 Such a strip-like electrical resistor can be made into a thin film or the like with a thickness of, for example, of the order of 1 ... 1.5 mm. There is no limit to the width. If desired, the resistor can be made uniformly annular, which can be pulled over the oil filter 5. Only the connecting wires 11, 12 of the resistor come out of this part.

The electric resistor 7 can be provided with an adhesive surface and thereby fastened to the sheath 51 of the oil filter 5. It can also be fixed 10 by means of tape, plastic film or the like 10. It is preferable to use a film covering the entire outer surface of the resistor 7. At the same time, this acts as a mechanical protection for the resistor.

The upper surface of the electric resistor 7, i.e. the outer surface 9a, can be provided with a film reflecting heat radiation back to the resistor 7. This can be an aluminum or similar metal foil. This heat-reflecting film can also be used to attach the resistor 7 to the surface of the oil filter 5.

20 The electric resistor 7 can also be placed completely inside the metal sheath. It is advantageous to leave the ends of the sheath free of the actual resistance wires or mesh. In this case, the ends of the jacket can be folded approx. 90 * outwards from the filter and a suitable quick connector or clamp, such as a screw fastening, can be arranged between them. This attachment allows the electrical resistor to be pressed tightly around the oil filter.

The magnitude of the resistor 7 is defined in such a way that the heat output is sufficient to raise the temperature of a few deciliters of oil in the oil filter 30 in 5 to 15 minutes above the ambient temperature by at least 30 '... 50 ° C. In conventional passenger cars, the thermal output of the resistor is of the order of 50. .. 200 W.

35 The strip-shaped electric resistor 7 is connected to a power supply 14 11 70454 such as a battery either directly via switch 15 or via a thermostat. The sensor of the thermostat is placed either inside or on the surface of the oil filter 5. The desired maximum temperature can be set and the thermostat monitors that this 5 is not exceeded. In addition, a timer 16 can be used, in which case, for example, heating can be started at the desired time before starting the engine.

The device according to the invention operates as follows. The heating resistor 7 of the device 10 is connected to the power supply 14, e.g. manually, by a switch 15. There is always a small amount, e.g. 2 dl, of oil in the space 53 of the filter 5, which starts to heat as the electric current passes through the resistor 7. After a suitable waiting time, eg 5 ... 15 minutes, the lubricating oil temperature has risen sufficiently high, eg 40 * ... 50 *, and the engine can be started. The thermostat will ensure that the oil temperature at a desired value, e.g. 90 ° C, higher, even though the waiting time longer than would be expected. This is particularly important when, after a desired time 20, the heating element 7 is connected to the power supply 14 by means of a timer 16. On the other hand, an indicator light located in the vehicle's instrument panel indicates when the desired temperature has been reached and start-up can take place.

25 As soon as the engine is started, the warm oil contained in the device 7 immediately sinks into the main oil channel 6 or the corresponding oil channel. The cold engine thus gets a warm oil bath immediately during its first spins; the rotational resistance of the motor is substantially reduced and starting is ensured.

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Claims (5)

6 70454 A device for improving the cold start of an internal combustion engine, comprising an oil filter (5) known per se and an electric resistor (7) placed on its outer surface 5, formed in a wide and thin strip and fixed around an oil filter (5), characterized in 7) is placed in connection with the base or mounting part (54) of the oil filter (5) close to the connection point of the oil filter (5) and the motor or the like, whereby heat is applied to the oil in the filter not only through the filter metal jacket but also along the metal parts the inner parts. Device according to Claim 1, characterized in that the thickness of the electrical resistor (7) is at most of the order of 2 to 3 mm. Device according to Claim 1 or 2, characterized in that the electrical resistor (7) is provided with an adhesive surface and is thereby attached to the oil filter. Device according to Claim 1 or 2, characterized in that the electrical resistor (7) is attached to the oil filter by means of tape, plastic film or the like (10). » Device according to one of the preceding claims, characterized in that the upper surface (9a) of the electric resistor (7) is provided with a heat-reflecting film. 30 II