DE102009009687A1 - Liquid-cooled internal combustion engine with at least two cylinders - Google Patents

Abstract

A liquid-cooled internal combustion engine having a crankcase with at least two adjacently arranged cylinders (1, 1 ') around which a coolant passage (2) extending radially in the longitudinal direction of an engine longitudinal axis (L) is arranged, wherein a cylinder head corresponding to the crankcase extends substantially in a cylinder longitudinal axis (Z) with fastening elements on the crankcase (1) can be arranged, wherein the fastening elements protrude largely parallel to the cylinder longitudinal axis (Z), on the cylinders (1, 1 ') opposite side of the coolant jacket (2) into the crankcase, wherein the coolant passage (2) in the crankcase extends completely around the fasteners. The embodiment according to the invention minimizes the power loss of the cooling system by reducing the flow pressure losses.

Description

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

It starts from the German publication DE 102 55 316 A1 from, from an internal combustion engine with a molded stiffening rib on the cylinder tube is known. The internal combustion engine has a crankcase with a cylinder bank, with a number of cylinders arranged in series, and with at least one respective cylinder bank associated fluid cooling system with at least one formed in the cylinder block fluid channel, which coolant through the cylinder block as a coolant jacket adjacent to the cylinders for the cooling thereof passes. Between the cylinders, a web portion is formed, which is not flowed through by the coolant. On the side opposite the web area of the coolant channel screwing pipes are arranged for mounting a cylinder head.

The technical environment is further on the European patent application EP 1 116 871 A2 referenced, in which also a crankcase with the same principle-related disadvantage of the DE 102 55 316 A1 is disclosed.

adversely in the described embodiment is the strong coolant deflection in the area of the bridge and the screw pipes, creating a high pressure loss occurs in the cooling system.

task It is the object of the present invention to provide the above mentioned o. To prevent disadvantage.

These The object is achieved by the feature in the characterizing part of the claim 1 solved.

By the embodiment of the invention is the power loss the cooling system by reducing the flow pressure losses minimized. In addition, the efficiency of the cooling system elevated. By this embodiment is in an advantageous Way of mastering significantly higher thermomechanical Cylinder head loads by the requirement for a good uniform distribution of the coolant part streams given in the cylinder head, in all cases where the Coolant inlet channels (coolant inlet opening with maximum coolant pressure) and / or the coolant drainage channels (Coolant transfer port with minimum Coolant pressure) integrated in the crankcase or are grown.

Further are the manufacturing costs of an inventive Crankcase significantly reduced, by the ability the die-casting process for closed-deck crankcases due to significant increase in strength of the disposable cores, which serve to produce the coolant spaces.

The Embodiment according to claim 2 is a particularly proven and robust coolant guide.

The Design of the flow cross-sections of the coolant jacket according to claim 3 has been in numerical Calculations and experiments proved to be particularly advantageous.

The Use of cylinder head bolts as fasteners for the cylinder head gem. Claim 4 is a particularly preferred Variant.

in the The invention is based on a particularly preferred embodiment explained in more detail in a single figure.

1 shows a plan view of a three-dimensionally illustrated casting core for a coolant jacket according to the invention.

1 shows a plan view of a three-dimensionally illustrated casting core for an inventively shaped coolant jacket 2 , The coolant jacket 2 is shown in a particularly preferred embodiment, for example, for a multi-cylinder internal combustion engine, with a front and a rear part 2 ' . 2 '' of the coolant jacket 2 are shown separately. An arrangement, or location of two cylinders is with 1 . 1' quantified. The coolant jacket 2 extends radially outward around the cylinder 1 . 1' largely in the longitudinal direction of an engine axis L and that both inlet side and outlet side and wraps on the coolant inlet openings 4 . 4 ' opposite side to the last cylinder 1 completely around. For the passage of coolant in a cylinder head, not shown, coolant transfer openings 3 . 3 ' provided, in this embodiment, between the web areas 5 . 5 ' are arranged. The majority of the coolant leaves the crankcase from a coolant outlet opening.

In other embodiments, the reversal of the flow direction of the coolant is possible, ie, the coolant inlet openings 4 . 4 ' become coolant outlet openings and the coolant outlet opening 6 becomes a coolant inlet opening. The coolant may also be via the coolant transfer ports 3 . 3 ' from the cylinder head into the coolant jacket 2 stream.

For screwing a cylinder head, not shown, largely in the direction of a cylinder axis Z are screw pipes for fastening provided in the gusset region of the web areas 5 . 5 ' are arranged. According to the invention, the coolant jacket extends 2 in the crankcase completely around the fasteners around. As already mentioned, the coolant jacket extends in this particularly preferred embodiment 2 on both sides of the cylinder 1 . 1' as well as in the front part 2 ' around a cylinder 1 around.

In a further embodiment, the coolant jacket can 2 also in the back part 2 '' around a cylinder 1 extend around or in the front and rear part 2 ' . 2 '' ,

Also Next is a flow cross-section of the coolant jacket 2 on the cylinders 1 . 1' opposite side of the fasteners at least 10% of a flow cross-section of the coolant jacket 2 between the cylinders 1 . 1' and the fasteners. As fasteners in particular cylinder head bolts have proven.

The embodiment according to the invention minimizes the power loss of the cooling system by reducing the flow pressure losses. This results in a higher efficiency of the cooling system, resulting in a control of significantly higher thermomechanical cylinder head loads by the requirement for a very good uniform distribution of the coolant partial flows in the cylinder head, in all cases in which the coolant inlet channels (coolant inlet openings 4 . 4 ' ) and / or the coolant drainage channels (coolant transfer openings 3 . 3 ' ) are integrated or mounted in the crankcase and / or in the cylinder head. This also applies to the above-mentioned further embodiments.

Further results from the inventive design a significant reduction in manufacturing costs through empowerment the die-casting process for closed-deck crankcases due to significant increases in strength of the disposable cores, the serve for the preparation of the coolant spaces.

1, 1'

cylinder

2

Coolant jacket

2 '

front Part of the coolant jacket

2 ''

rear Part of the coolant jacket

3, 3 '

Coolant transfer opening

4, 4 '

Coolant inlet opening

5, 5 '

web region

6

Coolant outlet opening

Z

cylinder longitudinal axis

L

Engine longitudinal axis

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• - DE 10255316 A1 [0002, 0003]
• - EP 1116871 A2 [0003]

Claims (4)

Liquid-cooled internal combustion engine having a crankcase with at least two cylinders arranged adjacent to one another ( 1 . 1' ) to the radially outside a largely in the longitudinal direction of an engine longitudinal axis (L) extending coolant jacket ( 2 ) is arranged, wherein a cylinder head corresponding to the crankcase largely in a cylinder longitudinal axis (Z) with fastening elements on the crankcase ( 1 ) can be arranged, wherein the fastening elements are substantially parallel to the cylinder longitudinal axis (Z) on which the cylinders ( 1 . 1' ) opposite side of the coolant jacket ( 2 ) protrude into the crankcase, characterized in that the coolant jacket ( 2 ) in the crankcase extends completely around the fasteners. Liquid-cooled internal combustion engine according to claim 1, characterized in that the coolant jacket on both sides of the cylinder ( 1 . 1' ) and the front side of the crankcase about a cylinder ( 1 . 1' ) extends around. Liquid-cooled internal combustion engine according to claim 1 or 2, characterized in that a flow cross-section of the coolant jacket ( 2 ) on the cylinders ( 1 . 1' ) opposite side of the fastening elements at least 30% of a flow cross-section of the coolant jacket ( 2 ) between the cylinders ( 1 . 1' ) and the fasteners. Liquid-cooled internal combustion engine after one of the claims 1 to 3, characterized that the fasteners are cylinder head bolts.