DE102014214185A1 - Four-stroke reciprocating internal combustion engine with a crank mechanism - Google Patents

Abstract

Four-stroke reciprocating internal combustion engine with a crank mechanism, with which a piston via a crank pin and a connecting rod in a cylinder of the internal combustion engine is displaceable positionally variable, wherein the crank pin is guided against rotation in a radially arranged in a first outer gear largely rectilinear backdrop, wherein the first external gear is rotatable about an axis of rotation and a second about the axis of rotation rotatable outer gear is provided with a on the piston facing end face largely round eccentric backdrop, in which engages the crank pin, wherein a third, provided with a fourth external gear rotatably connected external gear with the third outer gear meshing with the first outer gear and the fourth outer gear meshing with the second outer gear. The inventive design, the efficiency of the four-stroke reciprocating internal combustion engine is improved.

Description

The invention relates to a four-stroke reciprocating internal combustion engine with a crank mechanism with the features of the preamble of patent claim 1.

For technical environment is for example on the American patent US1,326,129 pointed. From this patent, a four-stroke reciprocating internal combustion engine with a crank mechanism is known, which is designed via gears such that the piston performs a larger expansion stroke than the compression stroke.

The diameters of the gears (Wälzkreisdurchmesser) are clearly defined by the crank radius of the crankshaft and the diameter ratio of the gears and not changeable. In addition, the sinusoidal stroke profile is determined by the crank radius, the eccentric and the connecting rod length.

The object of the present invention is o. G. To avoid disadvantages.

This object is achieved by a crank mechanism with the features of the characterizing part of patent claim 1.

Advantageously, the diameters of the first and the second gear, taking into account the translation freely selectable. In addition, in an advantageous manner, the sinusoidal stroke course is adjustable within certain limits by the design of the straight-line link, a guide track in the second gearwheel.

Advantageous developments of the invention are described in the subclaims.

Thus, the embodiments according to claims 2 and 3 are particularly preferred embodiments.

Further, the transmission ratio between the first and the second external gear according to claim 4 is preferably the factor 2: 1.

In order to avoid a one-sided loading of the crank mechanism or the connecting rod, a second crank drive is preferably provided in mirror image to the connecting rod according to claim 5.

In the following the invention with reference to an embodiment in two figures is explained in more detail.

1 shows an exploded view of a crank mechanism according to the invention for a four-stroke reciprocating internal combustion engine.

2 schematically shows the stroke of the piston over 720 ° crank angle.

1 shows an exploded view of a crank mechanism according to the invention 1 for a four-stroke reciprocating internal combustion engine. With the crank mechanism according to the invention 1 is a piston 2 via a crankpin 3 and a connecting rod 4 in a cylinder of the not shown four-stroke reciprocating internal combustion engine liftable variable position. The crankpin 3 is secured against rotation by a not numbered square in a radially in a first outer gear 5 arranged, largely linear backdrop 6 guided. The first external gear 5 is about a rotation axis 7 rotatable. Next is a second, about the axis of rotation 7 rotatable external gear 8th provided with one on the the piston 2 facing end face largely round eccentric backdrop 9 , In this largely round, eccentrically arranged backdrop 9 engages an extension of the crank pin 3 a, which is cylindrical at the end. Next is a third 10 , with a fourth external gear 11 rotatably connected external gear provided. The third external gear 10 meshes with the first external gear 5 and the fourth external gear 11 meshes with the second external gear 8th ,

Next, the second external gear 8th a coaxial circumferential groove in which the first external gear 5 is guided. In a further embodiment, the first external gear can also 5 have this coaxial groove. Thus, either the first external gear 5 in the second external gear 8th or the second external gear 8th in the first external gear 5 rotatably mounted. A gear ratio between the first and the second external gear 5 . 8th is 2: 1. In the embodiment shown here is a mirror image of the connecting rod 4 a second crank mechanism 12 intended. Thus, a uniform load of the crank mechanisms 1 . 12 guaranteed. All components can be represented for example from a ferrous material, as they are known from mechanical engineering.

2 shows schematically the stroke course of the piston 2 between 0 ° and 720 ° crank angle. How out 2 can be seen, the crank mechanism according to the invention in the expansion phase (360 ° to 720 °) on a twice as high stroke course as in the intake stroke (0 ° to 360 °). The stroke ratio does not necessarily have to be 2: 1, even 1.6: 1 to 2.5: 1 can be displayed. Thus, a much better efficiency for a four-stroke reciprocating internal combustion engine can be represented.

In contrast to the prior art, the diameters of the external gears are freely selectable taking into account the translation. The sinusoidal stroke course of the piston 2 is by the execution of the round backdrop 9 in the second external gear 8th adjustable within certain limits.

LIST OF REFERENCE NUMBERS

1

crankshaft

2

piston

3

crank pins

4

pleuel

5

first external gear

6

straightforward backdrop

7

axis of rotation

8th

second external gear

9

round backdrop

10

third external gear

11

fourth external gear

12

second crank mechanism

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• US 1326129 [0002]

Claims (5)

Four-stroke reciprocating internal combustion engine with a crank mechanism ( 1 ), with which a piston ( 2 ) via a crankpin ( 3 ) and a connecting rod ( 4 ) is positionally movable in a cylinder of the internal combustion engine, characterized in that the crankpin ( 3 ) secured against rotation in a radially in a first external gear ( 5 ) arranged largely linear backdrop ( 6 ), wherein the first external gear ( 5 ) about a rotation axis ( 7 ) is rotatable and a second about the axis of rotation ( 7 ) rotatable external gear ( 8th ), with one on the piston ( 2 ) facing end face largely round eccentrically arranged backdrop ( 9 ) into which the crankpin ( 3 ), with a third ( 10 ), with a fourth external gear ( 11 ) is provided rotatably connected external gear, wherein the third external gear ( 10 ) with the first external gear ( 5 ) and the fourth external gear ( 11 ) with the second external gear ( 8th ) combs. Internal combustion engine according to claim 1, characterized in that the second external gear ( 8th ) in the first external gear ( 5 ) is mounted rotatably. Internal combustion engine according to claim 1, characterized in that the first external gear ( 5 ) in the second external gear ( 8th ) is mounted rotatably. Internal combustion engine according to one of the claims 1 to 3, characterized in that a transmission ratio between the first ( 5 ) and the second external gear ( 8th ) is the factor 2: 1. Internal combustion engine according to one of the claims 1 to 4, characterized in that a mirror image of the connecting rod ( 4 ) a second crank drive ( 12 ) is provided.

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