DE8124564U1 - LIQUID-COOLED VEHICLE INTERNAL COMBUSTION ENGINE - Google Patents

Description

• »

• ·

suffered tCll

Liquid-cooled vehicle internal combustion engine

The invention relates to a liquid-cooled Vehicle internal combustion engine according to the preamble of claim 1.

In the known internal combustion engines with high efficiency, in particular diesel internal combustion engines

with direct injection, the heat content of that is enough

(Cooling liquid flowing through the heating system in particular at idle and in the lower part-load range at low outside temperatures does not result in a satisfactory Ensure heating of the passenger compartment. Additional heating is expensive and has high operating costs and are difficult to accommodate due to the limited space in the engine compartment.

The invention is based on the object of a liquid-cooled To create vehicle internal combustion engine in which the heat loss absorbed by the cooling liquid can be used to the greatest possible extent in the vehicle heating system.

According to the invention, this object is achieved in that the heat-radiating outer surfaces of the internal combustion engine are at least partially covered with thermal insulation.

The proposal according to the invention largely prevents the radiation of heat, which can amount to up to 25% of the heat of the coolant at low outside temperatures, and thus considerably increases the heat supply for the vehicle heating system. In addition, faster heating of the cooling liquid is achieved, which means that both the hot and cold

running phase of the internal combustion engine as well as the period is shortened until the vehicle heating system starts to work effectively. After all, the higher the temperature the coolant has a greater temperature difference in the heating heat exchanger, which can be designed smaller and a better degree of efficiency Has.

The thermal insulation can be made of a molded or sprayed-on layer of foam plastic.

·. 10 stand, which at the occurring temperatures of

is stable at around 120 ° C. As a suitable material

Polyurethane foam has proven itself, but other heat-insulating materials, such as foamed ones, can also be used Polycarbonates, polyesters, polyimides, and the like can be used. Instead of applying an insulating layer a self-supporting shell construction made of foam plastic can also be provided, which surrounds the internal combustion engine as completely as possible.

Alternatively, the internal combustion engine of a Be surrounded by the capsule and the space between

the outer surface of the internal combustion engine and the capsule

V 'can be filled with a heat insulating material.

The capsule can be made of sheet metal or plastic and the heat-insulating material can in turn a foam plastic or a mineral thermal

ί be insulating material such as rock wool or the like.

Since the temperature of the exhaust pipes is generally higher than the decomposition temperature of the thermal insulation, at least if this is made of foam plastic, the exhaust pipes can be spaced apart, the thermal insulation penetrating pipe socket umj be given. The space between the exhaust

tubes and the pipe socket can be attached to the coolant spaces the internal combustion engine to be connected to part of the exhaust heat for the vehicle heater to make usable.

An embodiment of the invention is shown in the drawing, which shows a heat-insulated internal combustion engine shows in a schematically illustrated engine compartment of a passenger car.

In the engine compartment 1 of a passenger vehicle 2, a water-cooled diesel internal combustion engine 3 is arranged, which drives the front wheels 5 of the motor vehicle via a transmission k. The internal combustion engine 3 has a cylinder block 6 with cooling water spaces 7, a cylinder head 8 with cooling water spaces 9, a valve cover 10 and an oil pan 11. The cooling water spaces 7 and 9 are connected to one another and via lines 12 and 13 to a cooler 14. The cooler 14 can be short-circuited in the usual way by a thermostatic valve lk 'during the warm-up phase of the internal combustion engine and supplied with cooling air by an electrically driven fan 15. The cooling water spaces 7 and 9 are also connected by lines 16 and 17 to a heating heat exchanger 18 through which heating air can be blown into the passenger compartment 20 of the vehicle by means of a heating fan 19. The heating output can be regulated by a valve 21 in the line 17.

Essentially the entire outer surface of the internal combustion engine 3 is covered by a heat insulating layer in the exemplary embodiment 22 covered. This insulating layer is preferably made of a foam plastic, such as polyurethane either in a form on the outer surfaces of the

■ · »111 ι ι ■ II * ■■ * · Il I 1 I I ι

• ·

Individual parts of the housing of the internal combustion engine 3, namely the cylinder block 6, the cylinder head 8, ί of the valve cover 10 and the oil pan 11, is sprayed on or is attached as a multi-part, self-supporting shell construction on the outer walls of these housing parts. ^%

The exhaust pipes 23 are each surrounded at a distance by a pipe socket 2k in order to protect the thermal insulation 22 from the hot exhaust pipes. The JRohr

(, 10 can trim to the cooling water spaces 9 of the cylinder

head 8 be connected. As a result, part of the exhaust gas heat is used for heating the vehicle made available.

The suction line is denoted by 25 and the air filter is denoted by 26.

In a modification of the illustrated embodiment, the thermal insulation of the internal combustion engine 3 can also take place in that the internal combustion engine with Distance surrounding capsule made of sheet metal or plastic

/ - · 20 is provided and the space between the

Capsule and the outer surface of the internal combustion engine is filled with a heat-insulating material that is resistant to the temperatures that occur. There are both mineral thermal insulation materials and thermal insulating plastics like the one before mentioned polyurethane in question.

«Ι α * · · i ■

• · " · IF

summary

To meet the heating requirements of a passenger car without additional heating units and without impairment the thermal efficiency of the internal combustion engine The internal combustion engine will cover even at low outside temperatures and also at low loads Provided with a thermal insulation, through which the heat loss due to radiation largely is prevented. In this way, on the one hand, rapid heating of the cooling water is achieved, and on the other hand a large part of the waste heat absorbed by the cooling water from the internal combustion engine for heating the vehicle made usable.

Claims (10)

Expectations 1. Liquid-cooled vehicle internal combustion engine, in particular diesel internal combustion engines with direct injection, A vehicle heating system can be connected to the rooms carrying the coolant, through this marked the heat-radiating outer surfaces of the internal combustion engine (3) at least partially with thermal insulation (22) are covered. 2. Liquid-cooled vehicle internal combustion engine according to claim 1, characterized in that the thermal insulation (22) consists of a foam plastic layer is formed. 3. Liquid-cooled vehicle internal combustion engine according to claim 2, characterized in that the foam plastic layer is applied directly to the outer surface the internal combustion engine (3) is applied. k. Liquid-cooled vehicle internal combustion engine according to Claim 2, characterized in that the thermal insulation (22) is provided by a self-supporting
Shell construction is formed from foam. 5- liquid vehicle internal combustion engine according to one of claims 2 to k, characterized in that polyurethane is used as the foam plastic. 6. liquid-cooled vehicle internal combustion engine according to claim 1, characterized in that the heat-radiating outer surfaces of the internal combustion engine (3) are surrounded by a capsule and
the space between the outer surface of the
Internal combustion engine and the capsule from one
insulating material is filled. 7. Liquid-cooled vehicle internal combustion engine according to claim 6, characterized in that the The capsule is made of sheet metal. 8. Liquid-cooled vehicle internal combustion engine according to claim 6, characterized in that the capsule consists of plastic. 9- Liquid-cooled vehicle internal combustion engine according to one or more of the preceding claims, characterized in that the exhaust • ·· · t · Μ «ft P ft ft ο β ■ ··· · · ft - 3 tubes (23) of spaced apart, the thermal insulation penetrating pipe socket (24) are surrounded. \ 10. Liquid-cooled vehicle internal combustion engine ί according to claim 9i characterized in that the Ji Pipe socket (2 ^) to the coolant spaces (9) § are connected. ψ III · ■ ■