The invention relates to a compact multi-cylinder internal combustion engine.
EP 1 146 219 A1 already discloses the arrangement of gas ducts in a cylinder head of a VR engine. In this case, one cylinder head is used for two rows of cylinders. The two rows of cylinders are arranged in a staggered manner and pushed into each other and drive a common crankshaft in a restricted manner. Inlet and outlet ducts are largely routed horizontally in the cylinder head, i.e. transversely to the cylinder axis. All the outlet ducts open out on one side of the cylinder head, all the inlet ducts open out on the opposite side. The outlet ducts of the row of cylinders which is in each case offset to the rear are considerably longer than those of the ones at the front. The inlet ducts also have these differences in length, but are arranged in a mirrored manner. This duct arrangement is not suitable for engines with which high powers are to be achieved at high engine speeds, as is required for example with motorcycle engines. In particular, high power densities cannot be achieved with the very unequal inlet ducts.
The object of the invention is to provide a suitable cylinder head for a multi-cylinder internal combustion engine with a VR cylinder arrangement, with which high engine powers can be achieved.
The solution is provided by the multi-cylinder internal combustion engine according to Claim 1 or 2.
Advantageous configurations are specified in the dependent claims.
According to Claim 1, the object is achieved in that the cylinder head comprises a group of two, three, four or five gas ducts per cylinder, the group comprising at least one outlet duct and at least one inlet duct, and the geometric arrangement of the inlet ducts of one group being the same for all the cylinders.
The fact that the geometric arrangement of the inlet ducts is equal for all the groups means that the shape and profile of the inlet duct for one inlet valve, or of the inlet ducts in the case of several inlet valves, of a cylinder are the same for all the cylinders. This means in particular that this same geometric arrangement of the inlet ducts for the cylinders of the rear row of cylinders is the same as the geometric arrangement of the inlet ducts of the front row of cylinders. The inlet ducts for the cylinders of the rear row of cylinders can be aligned in the same direction as the inlet ducts of the front row of cylinders, but they can also be arranged in a mirrored manner with respect to each other. An identical arrangement for all the cylinders is also advantageous for the outlet ducts. With all the arrangements mentioned, it is also advantageous if the dimensions of the gas ducts of each cylinder are the same.
The use of the same geometric arrangement of the gas ducts for the front and rear rows of cylinders means that the same flow conditions can be achieved for all the cylinders, so uniform engine running is ensured over the entire speed range. With the use of identically shaped inlet ducts for all the cylinders, high engine power and the greatest possible synchronisation and smooth running of the engine are achieved.
Claim 2 describes a further solution according to the invention such that, when the crankshaft lies transversely (transverse installation), the inlet ducts of the rear row of cylinders are arranged behind the rear camshaft and the inlet ducts of the front row of cylinders are arranged in front of the rear camshaft or, when the crankshaft lies longitudinally (longitudinal installation), the inlet ducts of one row of cylinders are arranged to the left of an outer camshaft and the inlet ducts of the other row of cylinders are arranged to the right of the said camshaft.
The described arrangement of the inlet ducts on both sides of the inlet-side camshaft ensures that inlet ducts of the same length and shape are used, which are also relatively short, as a result of which a high engine power and the greatest possible synchronisation and smooth running of the engine are likewise achieved.
In a particularly advantageous development of the solutions according to the invention according to Claims 1 and 2, the engine comprises six cylinders.
A favourable development of the solution according to Claim 2 is also that, when there is a plurality of identical valves per cylinder, the inlet ducts and outlet ducts of one cylinder form a group and the geometrical arrangement or shape of the inlet ducts of one group is the same for all the cylinders.
It is also advantageous that the geometrical arrangement (shape) of the outlet ducts of one group is the same for all the cylinders.
In a further configuration, the internal combustion engine according to the invention comprises two, three, four or five valves per cylinder and one or two spark plugs per cylinder. Two, three or four camshafts can be installed per cylinder head. The gas ducts of the inlet valves of one cylinder can be combined to form one duct. The use of two inlet valves and one outlet valve per cylinder has proven particularly advantageous. If a plurality of outlet valves is used per cylinder, it is likewise favourable to combine the outlet ducts of one cylinder belonging to the individual valves to form one outlet duct.
In one configuration, the internal combustion engine is installed in a motorcycle with a transverse crankshaft, which is also referred to as a transverse installation. Then the cylinder head covers a front row of cylinders and a rear row of cylinders.
In another configuration, the internal combustion engine is installed in a motorcycle with a longitudinal crankshaft, which is referred to as a longitudinal installation. Then the cylinder head covers a left row of cylinders and a right row of cylinders.
If a plurality of inlet valves is advantageously provided per cylinder, that is, in a group, the ducts of one cylinder belonging to the inlet valves branch out from one common duct. If a plurality of outlet valves are provided, the outlet ducts of a cylinder belonging to the outlet valves merge to form one outlet duct.
Advantageously, the inlet ducts lead upwards and the outlet ducts run in a curved manner to one side or to both sides in a mirrored arrangement.
The forwardly curved outlet ducts of the rear row of cylinders are arranged between the forwardly curved outlet ducts of the front row of cylinders, the outlet duct of the outermost cylinder of the rear row of cylinders being arranged adjacently to the outlet duct of the cylinder of the front row of cylinders situated in front of it.
The cylinder head can be designed with one, two or three camshafts, the embodiments having two or three camshafts being particularly favourable. In the case of three camshafts, the central camshaft actuates the inlet valves of one row of cylinders and the outlet valves of the other row of cylinders. These valves are then arranged in an inclined manner with respect to each other. The front camshaft only actuates the outlet valves of the front row of cylinders, the rear camshaft only actuates the inlet valves of the rear row of cylinders. The valves are actuated directly by means of bucket tappets or else via rocker arms.
If two camshafts are used with transverse installation and identically aligned duct groups, the inlet ducts of the rear row of cylinders are arranged behind the rear camshaft and the inlet ducts of the front row of cylinders are arranged between the front and rear camshafts. In this case too, the valves are actuated directly by means of bucket tappets or via rocker arms.
If two camshafts are used with longitudinal installation, the inlet ducts of one row of cylinders lie to the left of one camshaft, the inlet ducts of the other row of cylinders lie to the right of the said camshaft.
If two camshafts are used with mirrored duct groups, all six inlet ducts are arranged between the two camshafts and lead upwards.
Alternatively, when three camshafts are used, the inlet ducts of the front row of cylinders can be arranged behind the central camshaft and in front of the rear camshaft, and the inlet ducts of the rear row of cylinders can be arranged behind the rear camshaft.
All the outlet ducts favourably open out of the cylinder head at the front, and the openings of the outlet ducts of the rear row of cylinders are offset to the rear in the longitudinal direction of the vehicle with respect to the those of the front row of cylinders.
It is also favourable that the duct dimensions of the gas ducts are the same for all the groups.
The alignment of the duct groups for the front and rear rows of cylinders can be the same but they can also be mirrored. In the case of mirrored arrangement of the groups, all the inlet ducts can open out in the top centre of the cylinder head and the outlet ducts can open out on both sides of the cylinder head. Conversely, all the outlet ducts can also run centrally and the inlet ducts can open out on both sides of the cylinder head.
If the outlet ducts run in a curved manner towards the front, then they run under the camshaft(s) situated in front of them. The outlet ducts are then situated under the central and front camshafts when three camshafts are used or only under the front camshaft when two camshafts are used.
The spark plugs are advantageously arranged centrally between the valves of the cylinders and lead upwards.
In a further embodiment, the internal combustion engine according to the invention comprises cylinders in the W arrangement, four rows of cylinders then being present with in each case one cylinder head for two rows of cylinders, two cylinder heads overall.
Exemplary embodiments of the multi-cylinder internal combustion engine according to the invention are presented in the figures described below. In particular, in the figures:
The parts mentioned in the text are indicated in the figures by the following reference symbols:
Further details can be found in the drawings of possible exemplary embodiments of the motorcycle internal combustion engine according to the invention below.
Number | Date | Country | Kind |
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10 2010 021 613 | May 2010 | DE | national |
10 2010 021 639 | May 2010 | DE | national |
20 2010 007 271 U | May 2010 | DE | national |
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/EP2011/058491 | 5/24/2011 | WO | 00 | 11/28/2012 |
Publishing Document | Publishing Date | Country | Kind |
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WO2011/147840 | 12/1/2011 | WO | A |
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2808041 | Dolza | Oct 1957 | A |
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20060011153 | Yamazaki | Jan 2006 | A1 |
20080168957 | Neese | Jul 2008 | A1 |
Number | Date | Country |
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10 2004 042 765 | Jun 2005 | DE |
1 146 219 | Oct 2001 | EP |
1 553 280 | Jul 2005 | EP |
860011 | Feb 1961 | GB |
62-228645 | Oct 1987 | JP |
Entry |
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Krueger, “Sechszylinder—Motoren Mit Kleinem V-Winkel”, MTZ Motortechnische Zeitschrift, Bd. 51, Nr. 10, pp. 410-418 (1990) (English Abstract on p. 2 of document). |
International Search Report of International Application No. PCT/EP2011/058491 dated Dec. 8, 2011 with English Translation. |
International Preliminary Report on Patentability of International Application No. PCT/EP2011/058491 dated Dec. 6, 2012 with English Translation. |
Number | Date | Country | |
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20130068190 A1 | Mar 2013 | US |