DE102008018575A1 - Internal combustion engine has combustion piston, where straight line movement over crank is converted in rotating motion of crankshaft, and hydraulic unit with propelled hydraulic lifting piston - Google Patents

Abstract

The internal combustion engine has a combustion piston (1), where straight line movement over a crank is converted in a rotating motion of a crankshaft (5), and a hydraulic unit with a propelled hydraulic lifting piston (6). The tap for a drive of the hydraulic lifting piston is carried in the force chain between the combustion piston and the crankshaft.

Description

The The invention relates to an internal combustion engine with a combustion piston, its rectilinear motion via a crank in a rotary motion a crankshaft is reacted, and with a hydraulic unit with a powered hydraulic piston.

Lorry or mobile work machines equipped with a hydraulic brake, Working or driving system are usually equipped a hydraulic pump, a self-contained and as such manageable Unit forms and the through the crankshaft of an internal combustion engine, for example, a diesel engine, directly or via an intermediate gearbox is driven. The disadvantage of this arrangement is that the linear movement of the combustion piston or the internal combustion engine first with the help of a connecting rod and a crankshaft in a rotary motion must be converted. In this conversion, it comes to considerable Conversion losses due to friction on the combustion piston and in the bearings of the crank mechanism. The rotational movement of the crankshaft is then by means of a lifting element such as swash plate, Inclined axis or eccentric again in a linear motion converted by hydro piston. Even with this transformation arise Friction losses. There are estimates that by the Transverse forces due to the change at the swash plate a swash plate pump, and the consequent friction of the hydraulic piston in the piston bore about 70% of the hydraulic-mechanical Losses arise.

The Movement transformations will be avoided if, as already known is, the hydraulic piston of a trained as a free piston engine Internal combustion engine is driven. The free-piston machine, however, has inherent other disadvantages, such as the undefined Dead center or the uneven noise.

aim So it is, a conventional internal combustion engine with a combustion piston, whose rectilinear movement over a crank is converted into a rotational movement of a crankshaft, and a hydraulic unit with a driven hydraulic piston so together to combine that the above-described hydraulic-mechanical losses be reduced.

This Goal is achieved by an internal combustion engine, which according to the The preamble of claim 1, a combustion piston, the straight-line movement via a crank in a rotary motion a crankshaft is reacted, and a hydraulic unit with a having driven hydraulic piston and in accordance with the characterizing part of claim 1 of the tap for the drive of the hydraulic piston in the power chain between the combustion piston and the crankshaft in front of the crankshaft.

advantageous Embodiments of an internal combustion engine according to the invention can be found in the subclaims.

So are according to claim 2 of the combustion piston and the hydraulic piston rigidly connected together and the crankshaft is with the unit of combustion piston and hydraulic piston over a Crank loop connected. The loop of the crank loop is in formed of the rigid connection between the combustion piston and the hydraulic piston. The crank carries a sliding block in the loop is guided.

According to claim 3 are, as usual today, the combustion piston and the crankshaft connected together via a connecting rod are, which is hinged to a crank pin of the crankshaft. Of the Hydro piston is also on egg nem crank pin of the crankshaft hinged and acts with a pivotally mounted hydraulic cylinder together. Of course, hydraulic pistons and hydraulic cylinders can also be reversed, so that then the hydraulic cylinder on a crank pin the crankshaft is articulated and the hydraulic piston is pivotally mounted.

According to claim 4 may be a connecting rod between the combustion piston and the crankshaft on a first crankpin of the crankshaft and the hydraulic piston be hinged to a second crankpin of the crankshaft, wherein then the two cranks of different lengths and an angle with each other can include.

Two Embodiments of an inventive Internal combustion engine are shown in the drawing. Based on Drawing, the invention will now be explained in more detail.

It demonstrate

1 the first embodiment in which a combustion piston and a hydraulic piston are rigidly interconnected, in two highly schematic representations and

2 the second embodiment, in which a combustion piston and a hydraulic piston via a connecting rod and two cranks are connected to each other in two highly schematic representations.

According to 1 are all, some or just a combustion piston 1 a one or more of these pistons having internal combustion engine rigid with a hydraulic piston 6 connected to a hydraulic pump, which may be designed so that it can also work as a hydraulic motor. The combustion pistons are in a housing 2 guided in a straight line. The axes of the rigidly connected combustion pistons and hydraulic pistons coincide. In the rigid connection there is a cross loop 3 on which a sliding block 4 in a direction perpendicular to the direction of movement of the combustion piston and hydraulic piston is performed. The sliding block is rotatable on a crankpin of the crankshaft 5 stored.

The cross bow 3 moves here in a straight line oscillating in the housing 2 so that the movement of the combustion piston is transmitted to the hydraulic piston without prior conversion to rotary motion.

Through the crankshaft 5 is in conjunction with the sliding block 4 and the cross bow 3 a synchronization charge change and piston stroke as in conventional internal combustion engines possible (continue, for example, also injection and ignition). The coupling of several of in 1 shown engine units by means of a common crankshaft. This can also drive for ancillaries, z. B. a generator or an additional hydraulic pump.

A volume flow adjustment of the pump could be realized, for example, as a phase control, as shown in the WO 2004/025 122 A1 is described.

According to 2 are all, some or just a combustion piston 1 a one or more of these pistons having internal combustion engine and a crankshaft 5 in a conventional manner in the manner of a crank over a connecting rod 13 and one on the crankshaft 5 attached crankpins 14 connected with each other. The combustion pistons are in a housing 2 guided in a straight line. On the crankshaft is a second crank pin 15 , opposite the first crankpin 14 is angularly offset and whose distance from the axis of the crankshaft is smaller than the distance of the first crank pin 14 , The associated crank length is thus smaller than the first crank pin 14 , At the crank pin 15 is rotatable a hydraulic piston 6 hinged into a hydraulic cylinder 16 dips, which swivels on the housing 2 is stored.

Upon rotation of the crankshaft 5 Thus, a relative movement between the hydraulic piston 6 and the hydraulic cylinder 16 and causes a pumping action.

By the opposite effective direction of the compressive forces on the combustion piston and on the hydraulic piston, the engine bearing is relieved, so that the mechanical efficiency is improved.

Here is through the crankshaft 5 in connection with the connecting rod 13 and the combustion piston 1 a synchronization charge change and piston stroke as in conventional internal combustion engines possible (continue, for example, also injection and ignition). The coupling of several of in 2 shown engine units by means of a common crankshaft. This can also drive for ancillaries, z. B of a generator or an additional hydraulic pump serve.

A volume flow adjustment of the pump could also in the embodiment according to 2 For example, be realized as a phase control, as shown in the WO 2004/025 122 A1 is described.

at an internal combustion engine according to the invention with Hydraulic machine becomes the overall efficiency of the overall system Combustion engine-hydraulic unit opposite known solutions significantly improved. Many moving, heavily loaded components are eliminated. By the opposite Arrangement of combustion piston and hydraulic piston are the different ones Media fuel and hydraulic fluid easily and safely from each other separated. For additional engine operation of the hydraulic machine can be transmitted over the crankshaft power briefly over the amount to be provided by the internal combustion engine can be increased. Unlike a free piston machine, the combustion process is easy synchronizable with the piston stroke. unlike a free piston machine Other ancillaries can be easily driven become.

It is a compact design possible. The unit can be for regenerative applications where braking energy is stored and is used again. It is an operator of the hydro unit possible on a constant pressure network.

One Internal combustion engine according to the invention with hydraulic unit is mainly used in construction, agricultural and forestry machinery, in buses and in To use municipal vehicles with advantage. However, they are conceivable also stationary supply units with internal combustion engines, such as in shipbuilding.

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

• WO 2004/025122 A1 [0017, 0022]

Claims (7)

Internal combustion engine with a combustion piston ( 1 ), whose rectilinear movement via a crank into a rotational movement of a crankshaft ( 5 ) and with a hydraulic unit with a driven hydraulic piston ( 6 ), characterized in that the tap for the drive of the hydraulic piston ( 6 ) in the force chain between the combustion piston ( 1 ) and the crankshaft ( 5 ) takes place in front of the crankshaft. Internal combustion engine according to claim 1, characterized in that the combustion piston ( 1 ) and the hydraulic piston ( 6 ) are rigidly connected to each other and the crankshaft ( 5 ) with the unit of combustion piston and hydraulic piston via a cross loop ( 3 ) connected is. Internal combustion engine according to claim 1, characterized in that the combustion piston ( 1 ) and the crankshaft ( 5 ) via a connecting rod ( 13 ) which are connected to a first crank pin ( 14 ) of the crankshaft ( 5 ) and that the hydraulic piston ( 6 ) on a second crankpin ( 15 ) of the crankshaft ( 5 ) is articulated and with a pivotally mounted hydraulic cylinder ( 16 ) cooperates. Internal combustion engine according to claim 3, characterized in that the combustion piston ( 1 ) and the crankshaft ( 5 ) via a connecting rod ( 13 ) which are connected to a first crank pin ( 14 ) of the crankshaft ( 5 ) is articulated that the hydraulic piston ( 6 ) on a second crankpin ( 15 ) of the crankshaft ( 5 ) and that the crank length of the second crankpin is different from the crank length of the first crankpin. Internal combustion engine according to claim 4, characterized in that the crank length of the second crank pin ( 15 ) shorter than the crank length of the first crankpin ( 14 ). Internal combustion engine according to one of claims 3 to 5, characterized in that the combustion piston ( 1 ) and the crankshaft ( 5 ) via a connecting rod ( 13 ) which are connected to a first crank pin ( 14 ) of the crankshaft ( 5 ) is articulated that the hydraulic piston ( 6 ) on a second crankpin ( 15 ) of the crankshaft ( 5 ) and that the two to the crank pin ( 14 . 15 ) belonging cranks enclose an angle with each other. Internal combustion engine according to claim 6, characterized in that the crank length of the second crank pin ( 15 ) shorter than the crank length of the first crankpin ( 14 ).