V-internal combustion engine with a coolant flow balanced across all cylinders

Abstract

V-internal engine, wherein the internal combustion engine (2) comprises cylinders (3) arranged in a first row (4) and cylinders arranged in a second row (5) of the internal combustion engine (2), and a coolant passage that directs a coolant through the internal combustion engine (2), wherein the coolant passage comprises an inlet channel (15) arranged in a space between the rows (4, 5) of the internal combustion engine (2) and configured to receive coolant from an engine inlet line (6) and direct it to a cylinder circuit (21 to 23) in which the coolant cools the respective cylinders (3), and an outlet channel (18) configured to receive coolant from the respective cylinder circuits (21 to 23) and direct it to an engine outlet line (8), characterized in thatthat the exhaust port (18) in an engine block of the internal combustion engine (2) is arranged in a position halfway between the first row (4) and the second row (5) and below the intake port (15).

Description

Background of the invention and prior art

[0001] The present invention relates to a V-internal combustion engine according to the preamble of claim 1.

[0002] A conventional V-shaped internal combustion engine comprises a first group of cylinders arranged in a first bank on one side of the engine and a second group of cylinders arranged in a second bank on the opposite side. The engine includes a coolant passage for coolant that circulates within a cooling system. This coolant passage may include an intake port that directs coolant to the individual cylinders. The intake port may be located in a space between the banks. The coolant is directed from the intake port to the cylinder circuits for cooling each cylinder. The coolant exiting the respective cylinder circuits is received in an exhaust port. The exhaust port is typically shaped as a ramp that extends outside and around a large portion of the engine.This type of exhaust ramp design can lead to an unbalanced coolant flow due to the varying coolant path lengths from the individual cylinders to the ramp's outlet. Furthermore, an externally mounted exhaust ramp requires additional installation space and increases the engine's weight. Additionally, such an exhaust ramp has a number of sealing surfaces, posing a potential risk of coolant leakage from the cooling system.

[0003] DE 40 01 140 C1 discloses a cylinder block for a liquid-cooled V-internal combustion engine. An intake port supplies coolant to the cylinders, and an exhaust port receives coolant from the cylinders. The ports are arranged side by side within the internal free V-angle of the cylinder block, with a cover. Thus, the intake and exhaust ports are each positioned closer to one row of cylinders than to the other. Consequently, the intake coolant port must supply coolant to each cylinder in one of the rows via a transverse coolant passage extending past the exhaust coolant port. Similarly, the exhaust coolant port must receive coolant from the cylinders of the rows via a transverse coolant passage extending past the intake coolant port. This design increases the flow resistance of the coolant in the internal combustion engine.

[0004] Other internal combustion engines, especially in V-design, with cylinder cooling are known, for example, from US 4,559,908 A, US 2003 / 0121483 A1, DE 2 015 546 A, US 4,745,885 A and DE 100 21 526 A1. Brief description of the invention

[0005] The object of the present invention is to provide a V-internal combustion engine that has a balanced cylinder flow. Another object is to provide an exhaust port that does not increase the weight of the internal combustion engine.

[0006] The aforementioned problem is achieved by the internal combustion engine according to the characterizing part of claim 1. Thus, the exhaust port in the engine block is arranged in a position halfway between the first and second rows of cylinders. This design makes it possible to direct the coolant from the respective cylinders to the exhaust port via flow passages of the same length and to provide a substantially similar, balanced flow rate from all cylinders to the exhaust port. Consequently, the flow rate through the cylinders does not need to be dimensioned for the cylinder with the lowest flow rate. Therefore, it is not necessary to pump an excessively high flow rate through some cylinders to provide the necessary cooling for a cylinder with the lowest flow rate.Since the exhaust port is located inside the engine block of the internal combustion engine, the coolant can provide increased cooling of the engine. This makes it possible to achieve the necessary cylinder cooling with a lower coolant flow rate and reduced pumping effort. Furthermore, an exhaust port integrated into the engine block does not increase the engine's weight. If the exhaust port is cast directly into the engine block, the block's weight can be reduced. With the intake and exhaust ports integrated into the engine block, there are fewer sealing surfaces, minimizing the risk of leakage.

[0007] According to one embodiment of the invention, the exhaust port extends substantially over the entire length of the internal combustion engine. In this case, the exhaust port is able to receive coolant from all cylinders in the respective rows of the internal combustion engine via short flow passages of equal length. The exhaust port can extend in a straight line over its entire length. In this case, the flow resistance in the exhaust port is very low.

[0008] According to one embodiment of the invention, the exhaust port can be divided into two longitudinal channel sections. The stress on the engine block can be high during operation of the internal combustion engine. Dividing the exhaust port into two parallel sections can increase the strength of the engine block. In this case, a first channel section can receive coolant from the cylinders in the first row, and a second channel section can receive coolant from the cylinders in the second row, and the exhaust flows can converge in one exhaust section.

[0009] According to one embodiment of the invention, the intake port can extend substantially over the entire length of the internal combustion engine. The intake port and the exhaust port can be of equal length. In this case, the intake port is able to guide the coolant from all cylinders in the respective rows of the internal combustion engine through short flow paths of equal length. The intake port can extend in a straight line over its entire length. In this case, the flow resistance in the intake port is very low.

[0010] According to one embodiment of the invention, the intake port is connected to the engine intake line, and the exhaust port is connected to the engine exhaust line on the same side of the internal combustion engine. If the internal combustion engine is cooled by a coolant in a cooling system that cools only the internal combustion engine, it is usually convenient to connect the engine intake line to the intake port and the engine exhaust line to the exhaust port on the side of the internal combustion engine that is closest to a vehicle radiator in the cooling system, in order to minimize the length of the cooling system lines. Alternatively, the intake port can be connected to the engine intake line, and the exhaust port can be connected to the engine exhaust line on opposite sides of the internal combustion engine.If the cooling system cools an additional component besides the internal combustion engine, it is usually appropriate to connect the exhaust port to an engine exhaust pipe located on the side of the internal combustion engine closest to the additional component. This additional component, in the form of a retarder cooler, is typically located on the opposite side of the internal combustion engine from the vehicle radiator.

[0011] According to one embodiment of the invention, the intake port includes at least part of an oil cooler. During operation of the internal combustion engine, engine oil must be cooled in an engine oil cooler, and transmission oil must be cooled in a transmission cooler. It is advantageous to arrange at least one of the oil coolers in the intake port of the internal combustion engine. In this case, the coolant in the intake port cools the oil in the oil cooler before it cools the cylinders.

[0012] The oil cooler can be positioned midway between the first and second cylinder banks. In this case, the coolant comes into heat transfer contact with the heat exchanger as it flows through the intake port. The oil cooler can be an engine oil cooler or a transmission oil cooler. There can also be both an engine oil cooler and a transmission oil cooler in the intake port. The engine oil cooler and the transmission oil cooler can be positioned at different longitudinal angles, with one oil cooler located downstream of the other in the intake port. Alternatively, the intake port may include at least part of a first oil cooler located near the first cylinder bank and at least part of a second oil cooler located near the second cylinder bank. In this case, the coolant can flow through the respective oil coolers as it is directed to the cylinder in the cylinder banks.

[0013] According to one embodiment of the invention, the cylinder passages are designed to provide differentiated cooling of various zones in connection with the cylinder. A first zone can be the lower part of a cylinder head, a second zone can be the upper part of the cylinder head, a third zone can be the upper part of a cylinder liner, and a fourth zone can be the lower part of the cylinder liner. It is possible to provide differentiated cooling in the zones according to the cooling requirements in the respective zones. The coolant from the intake port can be directed first to the zones with a high cooling requirement and then to the zones with a lower cooling requirement. Furthermore, the coolant flow rate can be higher in the zones with a high cooling requirement than in the zones with a lower cooling requirement.The zone encompassing the lower part of the cylinder head typically has the highest cooling requirement of the previously mentioned zones. Brief description of the drawings

[0014] Preferred embodiments of the invention are described below as examples with reference to the accompanying drawings. These show: Fig. 1 a cooling system for a V-internal combustion engine, Fig. 2 a cross-sectional view through the internal combustion engine in plane AA from Fig. 1, and Fig. 3 a cross-sectional view through an internal combustion engine of an alternative embodiment. Detailed description of preferred embodiments of the invention

[0015] Fig. Figure 1 schematically shows a disclosed vehicle 1 powered by a V-internal combustion engine 2. In this embodiment, the internal combustion engine can be a V8, but can have a larger or smaller number of cylinders. Thus, its eight cylinders 3 are arranged in two separate banks 4, 5. The internal combustion engine 2 can be a diesel engine. The vehicle 1 can be a heavy vehicle. The vehicle 1 includes a cooling system for cooling the internal combustion engine 2. The cooling system includes an engine inlet line 6 that supplies coolant to the internal combustion engine 2. The engine inlet line 4 is equipped with a pump 7 that circulates coolant within the cooling system. The coolant leaving the internal combustion engine 2 is received in an engine outlet line 8. In this case, the engine outlet line 8 includes a retarder cooler 9.The cooling system can cool other components located near the internal combustion engine, such as a turbocharger, exhaust gas recirculation (EGR) in an EGR cooler, etc. A thermostat 10 is located at the end of the engine exhaust line 8. If the coolant temperature is lower than the thermostat 10's set temperature, it directs the coolant to a vehicle radiator bypass line 11 and back to the engine intake line 6 without cooling. If the coolant temperature is higher than the set temperature, the thermostat 10 directs the coolant to a vehicle radiator 12 located at the front of the vehicle 1. A vehicle radiator fan 13 and ram air provide a cooling airflow through the vehicle radiator 10 during vehicle 1 operation. A return line 14 receives the coolant from the vehicle radiator 12 and returns it to the engine intake line 6.

[0016] Fig. Figure 2 shows a cross-sectional view of the internal combustion engine 2. The coolant from the engine intake line 6 is received in an intake port 15 of the internal combustion engine 2. The intake port 15 extends in a straight line substantially over the entire longitudinal length of the internal combustion engine 2. In this case, the intake port 15 is defined by two side walls 16a, 16b, an upper wall formed by a closing element 17, and a lower wall formed by an outlet port 18 for the coolant. The outlet port 18 extends in a straight line substantially over the entire longitudinal length of the internal combustion engine 2. The intake port 15 and the outlet port 18 can be formed by a casting process of the engine block. The side wall 16a includes an opening in which an engine oil cooler 19 is arranged. The other side wall 16b includes an opening in which a transmission oil cooler 20 is arranged.The oil coolers 19, 20 have the same design. The oil coolers 19, 20 include concealed tubes that guide the oil through them and a plurality of plate-shaped heat transfer fins 19a, 20a. In this case, the heat transfer fins 19a, 20a are arranged in a horizontal plane. The coolant in the inlet port 15 is guided, essentially in the same proportions as in the cylinders 3, through the openings in the side walls 16a, 16b and the spaces between the heat transfer fins 19a, 20a of the coolers 19, 20.

[0017] The coolant exiting the intake port 15 is received in a cylinder circuit 21 to 23 for each cylinder 3. Each cylinder circuit comprises a schematically indicated intake passage 21, which receives coolant from the intake port 15; cooling passages 22, in which the coolant cools various zones I to IV of the cylinder 3; and a schematically indicated exhaust passage 23, which directs the coolant to the exhaust port 18. The cooling passages include a first cooling passage 22a, which cools a first zone I in the form of a lower part of a cylinder head; a second cooling passage 22b, which cools a second zone II in the form of an upper part of the cylinder head; a third cooling passage 22c, which cools a third zone III in the form of an upper part of a cylinder liner; and a fourth cooling passage 22d, which cools a fourth zone IV in the form of a lower part of the cylinder liner.In this case, the entire coolant flow rate is directed from the inlet passage 21 to the first cooling passage 22a. The first cooling passage 22a comprises a number of parallel channels extending through the lower part of the cylinder head.

[0018] A first portion of the coolant exiting the first coolant passage 22a is routed to the second coolant passage 22b. The second coolant passage 22b comprises a number of parallel channels extending through the upper part of the cylinder head. The coolant exiting the second coolant passage 22b is routed via the exhaust passage 23 to the exhaust port 18. A second portion of the coolant exiting the first coolant passage 22a is routed to the third coolant passage 22c. The third coolant passage 22c comprises a number of parallel channels extending through the upper part of the cylinder liner. The coolant exiting the third coolant passage 22c is routed via the exhaust passage 23 to the exhaust port 18. A third portion of the coolant exiting the first coolant passage 22a is routed to the fourth coolant passage 22d.The fourth cooling passage 22d comprises a number of parallel channels extending through the lower part of the cylinder liner. The coolant exiting the fourth cooling passage 22d is directed to the exhaust port 18 via the exhaust port 23.

[0019] The cooling effect in zones I-IV varies with the coolant flow rate and temperature. In this case, the entire flow rate is initially directed through zone I and the lower part of the cylinder head. Consequently, the most effective cooling is provided in zone I. The remaining cooling passages 22b to d have a lower coolant flow rate and a higher temperature than the first cooling passage 22a. The remaining cooling passages 22b to d can be designed to receive varying proportions of the coolant flow from the first cooling passage 22a, depending on their respective cooling requirements.

[0020] Thus, the coolant leaving cylinder circuits 21 to 23 is received in the exhaust port 18. The exhaust port 18 discharges the coolant flow from the internal combustion engine 2. The engine exhaust line 8 discharges the coolant from the internal combustion engine 2 on one side of the engine, located near the retarder cooler 9. The intake port 15 receives the coolant from the engine intake line 6 on one side of the internal combustion engine 2, located near the vehicle radiator 12. Consequently, the exhaust port 18 discharges the coolant from the internal combustion engine 2, and the intake port receives the coolant into the internal combustion engine 2 on opposite sides of the engine. The exhaust port 18 is located in the engine block midway below rows 4 and 5 and below intake port 5 and oil coolers 19 and 20.The design of the cooling passage through the internal combustion engine 2 makes it possible to provide a similar coolant flow rate through all cylinders 3. Furthermore, the intake port 15 and the exhaust port 18 have protected positions in the engine block and do not increase the weight of the internal combustion engine 2.

[0021] Fig.Figure 3 shows a cross-sectional view through an alternative internal combustion engine 2. In this case, the exhaust port 18 comprises a first longitudinal section 18a, which receives coolant from the cylinders 3 in the first row 4, and a second longitudinal section 18b, which receives coolant from the cylinders 3 in the second row 5. The first section 18a and the second section 18b are separated by a partition 18c, which is positioned midway between rows 4 and 5. Furthermore, an oil cooler 19 is arranged in the intake port 15, also midway between rows 4 and 5. In this case, the oil cooler 19 comprises plate-shaped heat transfer fins 19a, which are arranged in perpendicular planes extending longitudinally along the intake port 15.

[0022] The invention is not limited to the described embodiment, but can vary freely within the scope of the claims. Reference symbol list 1 vehicle 2V internal combustion engine 3 cylinders 4, 5 rows (of cylinders) 6 Engine intake pipe 7 Pump 8 Engine exhaust pipe 9 Retarder coolers 10 Thermostat 11 Vehicle radiator bypass line 12 vehicle radiators 13 vehicle cooling fans 14 Return line 15 Inlet channel 16a, 16b Side walls 17 Locking element 18 Outlet channel 19 Engine oil coolers 19a, 20a Heat transfer fins 20 Gear oil coolers 21 Admission lane 22 Cooling cycle 22a first cooling cycle 22b second cooling cycle 22°C third cooling cycle 22d fourth cooling cycle 23 Outlet passage

Claims

V-internal engine, wherein the internal combustion engine (2) comprises cylinders (3) arranged in a first row (4) and cylinders arranged in a second row (5) of the internal combustion engine (2), and a coolant passage that directs a coolant through the internal combustion engine (2), wherein the coolant passage comprises an inlet channel (15) arranged in a space between the rows (4, 5) of the internal combustion engine (2) and configured to receive coolant from an engine inlet line (6) and direct it to a cylinder circuit (21 to 23) in which the coolant cools the respective cylinders (3), and an outlet channel (18) configured to receive coolant from the respective cylinder circuits (21 to 23) and direct it to an engine outlet line (8), characterized in thatthat the exhaust port (18) in an engine block of the internal combustion engine (2) is arranged in a position halfway between the first row (4) and the second row (5) and below the intake port (15). Internal combustion engine according to claim 1, characterized in that the exhaust channel (18) extends substantially over the entire length of the internal combustion engine (2). Internal combustion engine according to claim 1 or 2, characterized in that the exhaust channel (18) extends in a straight line over its entire length. Internal combustion engine according to one of the preceding claims, characterized in that the exhaust channel (18) is divided into two longitudinal channel parts (18a, 18b). Internal combustion engine according to claim 4, characterized in that a first channel part (18a) receives coolant from the cylinders in the first row (4) and the second channel part receives coolant from the cylinders in the second row (5). Internal combustion engine according to one of the preceding claims, characterized in that the inlet channel (15) extends substantially over the entire length of the internal combustion engine (2). Internal combustion engine according to one of the preceding claims, characterized in that the inlet channel (15) extends in a straight line over its entire length. Internal combustion engine according to one of the preceding claims, characterized in that the inlet channel (15) is connected to the engine inlet line (6) and the outlet channel (18) is connected to the engine outlet line (8) on the same side of the internal combustion engine (2). Internal combustion engine according to one of claims 1 to 7, characterized in that the inlet channel (15) is connected to the engine inlet line (6) and the outlet channel (18) is connected to the engine outlet line (8) on opposite sides of the internal combustion engine (2). Internal combustion engine according to one of the preceding claims, characterized in that the inlet channel (15) includes at least a part of an oil cooler (19, 20). Internal combustion engine according to claim 10, characterized in that at least one oil cooler (19) is arranged in a position halfway between the first row (4) and the second row (5). Internal combustion engine according to claim 10, characterized in that the inlet channel (15) includes at least a part of a first oil cooler (19) located near the first row (4) and at least a part of a second oil cooler (20) located near the second row (4). Internal combustion engine according to one of the preceding claims, characterized in that the cylinder circuit (21 to 23) is designed in such a way that it provides differentiated cooling of different zones in connection with the cylinder (3). Vehicle comprising an internal combustion engine (2) according to any of the preceding claims.

Images