Adjustable connecting rod device for an internal combustion engine and internal combustion engine with such an adjustable connecting rod device

Abstract

Adjustable connecting rod device (1) for an internal combustion engine with adjustable compression ratio, comprising: a connecting rod (3) with a connecting rod eye (5) which has, at least in sections, a circumferentially varying connecting rod eye bearing width (a) with a maximum connecting rod eye bearing width (a) extending circumferentially along a connecting rod eye angle section (α) max ), wherein the connecting rod eye angle section (α) is spanned between a first trapezoidal attachment point (28) of the connecting rod eye (5) and a second trapezoidal attachment point (29) of the connecting rod eye (5); an eccentric device (10) which is accommodated at least in sections in the connecting rod eye (5) and is adjustable relative thereto, which has an eccentric device bearing width (b) which is assigned to the connecting rod eye bearing width (a) and which varies at least in sections circumferentially, with a maximum eccentric device bearing width (b) which extends circumferentially along an eccentric device angle section (β) max ), wherein the eccentric device angle section (β) is spanned between a first trapezoidal attachment point (36) of the eccentric device (10) and a second trapezoidal attachment point (37) of the eccentric device (10); wherein the varying connecting rod eye bearing width (a) of the connecting rod eye (5) is interrupted over a width (c) by an adjusting body (12) of the eccentric device (10); wherein the eccentric device angle section (β) is provided larger than the connecting rod eye angle section (α), and wherein the eccentric device angle section (β) is selected such that, when the eccentric device (10) is adjusted to end positions of a maximum effective connecting rod length (l eff_max ) or a minimum effective connecting rod length (l eff_min ) always completely covers the connecting rod eye angle section (α).

Description

[0001] The present invention relates to an adjustable connecting rod device for an internal combustion engine with adjustable compression ratio and to an internal combustion engine with such an adjustable connecting rod device.

[0002] Although applicable to any vehicle, the present invention and the problem underlying it are explained in more detail with reference to a passenger vehicle.

[0003] In internal combustion engines, a high compression ratio has a positive effect on the efficiency of the combustion engine. However, in an internal combustion engine with external ignition, especially a gasoline engine, which has a fixed compression ratio, the compression ratio may only be chosen to be so high that a so-called "knocking" of the internal combustion engine is avoided during full load operation. However, for the far more frequently occurring part load range of the internal combustion engine, i.e., at low cylinder filling, the compression ratio could be chosen with higher values without knocking occurring. The important part load range of the internal combustion engine can be improved if the compression ratio is variably adjustable. Various systems have been described for adjusting the compression ratio. For example, a variable connecting rod device can be provided to change the compression ratio.The effective connecting rod length of such an adjustable connecting rod device can be adjusted by rotating an adjustable connecting rod eye. Such an adjustable connecting rod device is also referred to as a so-called VCR (Variable Compression Ratio) connecting rod device. In an arrangement known to the applicant, the adjustment of the connecting rod eye is initiated by the action of inertia and gas forces from the internal combustion engine, with the rotary movement being supported by pistons pressurized with engine oil, which are arranged in the connecting rod. Due to the design, the moving masses in such a VCR connecting rod device are increased by the necessary additional components (eccentric, adjusting piston, etc.). To keep the increase in weight within limits, the bearing of the piston pin can be designed trapezoidally. This means that both the connecting rod eye and the eccentric are preferably provided with an identical trapezoidal geometry.However, unlike a conventional connecting rod without adjustment capability, this is not readily possible, as the piston pin mount (eccentric) can rotate relative to the connecting rod. This means that the forces acting on the piston cannot be transferred beyond the optimal bearing width of the connecting rod eye even with a corresponding adjustment of the eccentric. Edge formation and thus a possible local exceedance of the permissible surface pressure in the connecting rod eye area cannot be reliably prevented in this way. This is understandably something that must be avoided.

[0004] DE 10 2005 055 199 A1 discloses an adjustable connecting rod device for an internal combustion engine with an adjustable compression ratio. The connecting rod device comprises a connecting rod with a connecting rod eye having a connecting rod eye bearing width. Furthermore, the connecting rod device comprises an eccentric device that is at least partially received in the connecting rod eye and adjustable relative thereto, said eccentric device having an eccentric device bearing width.

[0005] US 2009 / 0 126 191 A1 discloses a connecting rod assembly for an internal combustion engine with a connecting rod having a connecting rod eye. The connecting rod eye has a circumferentially varying connecting rod eye bearing width.

[0006] DE 37 33 982 A1 and DE 101 24 862 A1 disclose trapezoidal connecting rods of an internal combustion engine.

[0007] The present invention is therefore based on the object of providing an improved adjustable connecting rod device which eliminates the above-mentioned disadvantages.

[0008] This object is achieved according to the invention by an adjustable connecting rod device having the features of patent claim 1 and by an internal combustion engine having the features of patent claim 8.

[0009] Accordingly, an adjustable connecting rod device for an internal combustion engine with an adjustable compression ratio is provided, comprising: a connecting rod with a connecting rod eye which, at least in sections, has a circumferentially varying connecting rod eye bearing width with a maximum connecting rod eye bearing width extending circumferentially along a connecting rod eye angle section, wherein the connecting rod eye angle section is spanned between a first trapezoidal attachment point and a second trapezoidal attachment point of the connecting rod eye;and an eccentric device which is at least partially received in the connecting rod eye and adjustable relative thereto, which has an eccentric device bearing width which is assigned to the connecting rod eye bearing width and which varies circumferentially at least in sections, with a maximum eccentric device bearing width which extends circumferentially along an eccentric device angular section, wherein the eccentric device angular section is spanned between a first trapezoidal attachment point and a second trapezoidal attachment point of the eccentric device; wherein the varying connecting rod eye bearing width of the connecting rod eye is interrupted over a width by an adjusting body of the eccentric device, wherein the eccentric device angular section covers the connecting rod eye angular section, and wherein the eccentric device angular section is provided to be larger than the connecting rod eye angular section.

[0010] The idea underlying the present invention is to provide a bearing width that varies at least in sections circumferentially on the connecting rod eye and on the eccentric device accommodated therein, at least in sections, wherein an angular section of the maximum bearing width of the eccentric device is provided larger than an angular section of the maximum bearing width of the connecting rod eye. This allows weight savings in the area of ​​the connecting rod eye by optimizing the bearing width to suit the load. At the same time, due to the overlap of the maximum bearing widths of the connecting rod eye and the eccentric device, a force acting from a piston on the connecting rod can be transmitted across the largest possible bearing width.Because the eccentric device angle section is larger than the connecting rod eye angle section, the eccentric device angle section overlaps the connecting rod eye angle section even in the end positions of the eccentric device. The trapezoidal cross section of the connecting rod eye does not extend into the connecting rod eye angle section, thus ensuring the load-bearing capacity of the connecting rod eye at all times. Furthermore, the trapezoidal cross section of the eccentric device does not extend into the eccentric device angle section.

[0011] The eccentric device's angle section is selected such that it always completely covers the connecting rod eye angle section when the eccentric device is adjusted to the end positions of a maximum effective connecting rod length or a minimum effective connecting rod length. The constant complete overlap of the maximum bearing widths of the connecting rod eye and the eccentric device ensures the functional reliability and wear resistance of the connecting rod device.

[0012] Furthermore, an internal combustion engine with such an adjustable connecting rod device is provided.

[0013] Advantageous embodiments and improvements of the present invention can be found in the subclaims.

[0014] According to a further preferred development of the adjustable connecting rod device, the connecting rod eye angle section corresponds to an effective angle section of a maximum piston force, whereby the critical / dominant gas force of the piston is transmitted to the connecting rod over the entire angle section by means of the maximum bearing width. This increases the service life and reliability of the adjustable connecting rod device.

[0015] According to a preferred embodiment of the adjustable connecting rod device, the maximum connecting rod eye bearing width and the maximum eccentric device bearing width are equal. This reliably prevents unfavorable edge formation and thus a possible exceeding of the surface pressure in the connecting rod eye area, thereby increasing the service life of the adjustable connecting rod device.

[0016] According to a further preferred development of the adjustable connecting rod device, an end section of the connecting rod associated with the connecting rod eye has, at least in sections, a trapezoidal cross-section oriented approximately parallel to a central axis of the connecting rod eye. This geometric contour is easy to manufacture, advantageously allowing for material savings in the area of ​​the connecting rod eye.

[0017] According to a preferred embodiment of the adjustable connecting rod device, the trapezoidal cross-section of the connecting rod tapers toward an end portion of the connecting rod eye. This allows for a load-adapted design of the connecting rod eye.

[0018] According to a preferred development of the adjustable connecting rod device, the eccentric device has an eccentric body that is at least partially received in the connecting rod eye. This enables simple assembly and manufacture of the eccentric device. This advantageously reduces the costs of manufacturing the adjustable connecting rod device.

[0019] According to a further preferred embodiment of the adjustable connecting rod device, the eccentric body has, at least in sections, a trapezoidal cross-section oriented approximately parallel to a central axis of the eccentric body. This geometric contour is easy to manufacture, advantageously allowing for material savings in the area of ​​the eccentric body.

[0020] The invention is explained in more detail below using exemplary embodiments with reference to the accompanying schematic figures of the drawing.

[0021] From the figures show: Fig. 1 Front view of a preferred embodiment of an adjustable connecting rod device; Fig. 2 a detailed view of the preferred embodiment of the adjustable connecting rod device according to Fig. 1; Fig. 3 a sectional view of the preferred embodiment of the adjustable connecting rod device according to the section line III-III according to Fig. 2; Fig. 4 a sectional view of an alternative preferred embodiment of the adjustable connecting rod device according to the section line III-III according to Fig. 2; and Fig. 5 a perspective detail view of the preferred embodiment of the adjustable connecting rod device according to Fig. 1.

[0022] In the figures, the same reference symbols denote the same or functionally identical components, unless otherwise stated.

[0023] The Fig. 1 illustrates a preferred embodiment of an adjustable connecting rod device 1 of an internal combustion engine (not shown). The internal combustion engine preferably has an adjustable compression ratio. The connecting rod device 1 is operatively connected, in particular, to a piston 2 of the internal combustion engine. The piston 2 is preferably arranged in a cylinder of the internal combustion engine and is subjected, for example, to a gas force F resulting from a combustion process taking place in the cylinder. The internal combustion engine preferably has a plurality of connecting rod devices 1, pistons 2, and cylinders.

[0024] The connecting rod device 1 preferably has a connecting rod 3 with a connecting rod eye 5 arranged at a first end section 4 of the connecting rod 3 and a crank bearing eye 7 arranged at a second end section 6 of the connecting rod 3. The first end section 4 is preferably formed integrally with the connecting rod eye 5. The second end section 6 is preferably formed integrally with the crank bearing eye 7. The crank bearing eye 7 has, in particular, a central axis 8. A bearing shell 9, in particular divided into two bearing half-shells, is preferably received in the crank bearing eye 7. The bearing shell 9 preferably has a hollow cylindrical shape. By means of the bearing shell 9, the connecting rod 3 is mounted on a connecting rod bearing journal of a crankshaft (not shown) of the internal combustion engine. The crank bearing eye 7 is preferably divided for assembly.The connecting rod eye 5 provided on the first end portion 4 of the connecting rod 3 preferably has an approximately hollow cylindrical geometry with a central axis 18. The central axis 18 is preferably oriented parallel to the central axis 8 of the crankshaft bearing eye 7 and arranged at a distance therefrom.

[0025] An eccentric device 10 of the connecting rod assembly 1 is received at least in sections in the connecting rod eye 5 and is designed to be adjustable relative thereto. The eccentric device 10 preferably has an approximately cylindrical eccentric body 11, which is received at least in sections in the connecting rod eye 5, and an adjusting body 12 which is operatively connected to the eccentric body 11, preferably in a rotationally fixed manner. The eccentric body 11 has a central axis which is identical to the central axis 18 of the connecting rod eye 5. The adjusting body 12 has an approximately triangular shape, with an eccentric rod 15, 16 being mounted on each end-side articulation section 13, 14 of the adjusting body 12. The eccentric rods 15, 16 are preferably operatively connected to working pistons (not shown), in particular hydraulic working pistons, of the connecting rod assembly 1.The working pistons are preferably arranged symmetrically with respect to a central plane 17 of the connecting rod 3 and are in particular integrated into the connecting rod 3. The central plane 17 preferably extends through the central axis 8 of the bearing eye 7 and through the central axis 18 of the connecting rod eye 5.

[0026] The eccentric body 11 preferably has an approximately cylindrical outer surface 19, which is in sliding engagement with an approximately cylindrical inner surface 20 of the connecting rod eye 5. The outer surface 19 is preferably designed as a bearing surface 19 of the eccentric body 11, and the inner surface 20 is preferably designed as a bearing surface of the connecting rod eye 5. The eccentric body 11 is pivotable about the central axis 18 in the connecting rod eye 5 by means of the adjusting body 12. The eccentric body 11 preferably has a piston bore 21 arranged eccentrically to its central axis 18 and having a central axis 22. A distance between the central axis 22 of the piston pin bore 21 and the central axis 8 of the crank bearing eye 7 is referred to as the effective connecting rod length l effThe center axes 8, 18, 22 preferably run spaced apart from one another and parallel to one another. In particular, a piston pin 23 is accommodated in the piston pin bore 21, which operatively connects the piston 2 to the connecting rod 3 by means of the eccentric body 11 of the eccentric device 10.

[0027] By adjusting the eccentric device 10, the effective connecting rod length l effof the adjustable connecting rod device 1. A rotation of the eccentric device 10 is initiated by the action of mass and gas forces of the internal combustion engine. The gas force F is dominant in conventional adjustable connecting rod devices. During a power stroke of the internal combustion engine, the directions of action of the forces acting on the eccentric device 10 change continuously. An adjustment movement of the eccentric device 10 is supported by the working pistons, which are preferably integrated in the connecting rod 3 and are pressurized with hydraulic fluid, in particular engine oil, or they prevent a resetting of the eccentric device 10 due to varying directions of force action. For example, when the eccentric device 10 is rotated in the direction of arrow 24, the effective connecting rod length l eff enlarged.

[0028] The connecting rod 3 is, as shown in the detailed view of the Fig. 2 and in the cross-sectional views according to the Fig. 3 and Fig. 4, illustrated, designed as a so-called trapezoidal connecting rod 3. The Fig. 3 illustrates a first preferred embodiment of the trapezoidal connecting rod 3 and the Fig. 4 illustrates a second, equally preferred embodiment of the trapezoidal connecting rod 3. The first end section 4 of the connecting rod 3 is tapered trapezoidally in the region of the connecting rod eye 5 in the direction of the piston 2. Preferably, the connecting rod 3 is constructed symmetrically with respect to a center plane 25. The center plane 25 preferably runs perpendicular to the center plane 17. The connecting rod 3 has, according to the embodiment of the Fig. 3 preferably has two bevels 26, 27 arranged symmetrically with respect to the center plane 25, which each extend from a trapezoidal attachment point 28, 29 towards an upper end section 30 of the connecting rod eye 5 assigned to the piston 2. Intersection points 28, 29 of horizontally running trapezoidal attachment lines 31, 32 with the inner surface 20 of the connecting rod eye 5 are defined as trapezoidal attachment points 28, 29. The trapezoidal attachment lines 31, 32 extend essentially perpendicular to the center lines 18, 22. This means that the connecting rod eye 5 tapers towards the upper end section 30. In contrast to the illustrated embodiment with linear bevels 26, 27, the bevels 26, 27 can be concave, convex, curved or have any desired geometry. The connecting rod eye 5 preferably has a circumferentially varying connecting rod eye bearing width a with a minimum connecting rod eye bearing width a assigned to the upper end section 30 minand a maximum connecting rod bearing width a assigned to a lower end section 40 of the connecting rod eye 5 max The varying connecting rod eye bearing width a is interrupted at a width c by the adjusting body 12, which is connected in a rotationally fixed manner to the eccentric body 11. The adjusting body 12 is preferably at least partially received in a groove 35 of the connecting rod 3. Starting from the lower end section 40 up to the trapezoidal attachment points 28, 29, extending in a z-direction, the connecting rod eye 5 preferably has the maximum bearing width a max The trapezoidal attachment points 28, 29 preferably align with the central axis 18 of the connecting rod eye 5 in a Fig. 2, in which the central axis 22 is arranged horizontally in line with the central axis 18, a connecting rod eye angular section α is defined. The connecting rod eye angular section α preferably corresponds to an effective angle section α of a maximum piston force caused by the gas force F. The position of the trapezoidal attachment points 28, 29 is ideally determined in a load-oriented manner according to the effective angle α of the maximum piston force. The connecting rod eye 5 therefore preferably has the maximum connecting rod eye bearing width a throughout the connecting rod eye angular section α. max on.

[0029] The eccentric device 10 or the eccentric body 11, which is at least partially accommodated in the connecting rod eye 5, preferably has a circumferentially varying eccentric device bearing width b assigned to the connecting rod eye bearing width a of the connecting rod eye 5. The eccentric device bearing width b can, at least in sections, coincide with the connecting rod eye bearing width a. The eccentric body 11 preferably has bevels 33, 34 arranged symmetrically with respect to the center plane 25, analogous to the connecting rod 3. The course of the bevels 33, 34 is arbitrary. The eccentric body 11 preferably has a maximum eccentric device bearing width b assigned to the lower end section 40 of the connecting rod eye 5. max and a minimum counter bearing width b assigned to the end section 30 of the connecting rod eye 5 min Preferably, the maximum connecting rod eye bearing width a max the maximum eccentric bearing width b max. The minimum connecting rod bearing width a min can be the minimum eccentric device bearing width b min correspond. Preferably, the eccentric body 11 has a first trapezoidal attachment point 36 and a second trapezoidal attachment point 37, between which an eccentric device angular section β is spanned, in particular with the central axis 18. Intersection points 36, 37 of horizontally extending trapezoidal attachment lines 38, 39 with the outer surface 19 of the eccentric body 11 are defined as trapezoidal attachment points 36, 37 of the eccentric body 11. The trapezoidal attachment lines 38, 39 run essentially perpendicular to the central axes 18, 22. The eccentric device angular section β has, for example, a value of 180°. The eccentric body 11 preferably has the maximum eccentric device bearing width b throughout the eccentric device angular section β. maxThe trapezoidal attachment points 36, 37 of the eccentric body 11 are preferably arranged in the z-direction above the trapezoidal attachment points 28, 29 of the connecting rod 3 or the connecting rod eye 5. For example, the eccentric device angular section β overlaps the connecting rod eye angular section α at least when the eccentric device 10 is adjusted over an adjustment range thereof, wherein the adjustment range of the eccentric device 10 corresponds in particular to the eccentric device angular section β.

[0030] The eccentric device angle section β is selected such that when the eccentric device 10 is adjusted to the end positions of a maximum effective connecting rod length l eff_max or a minimum effective connecting rod length l eff_minthe connecting rod eye angular section α is always completely covered. The eccentric device angular section (β) is provided to be larger than the connecting rod eye angular section (α). Complete covering is also to be understood, for example, as a position of the eccentric body 11 in which, for example, the trapezoidal attachment points 28, 36 approximately cover one another, i.e., have approximately the same z-position, or in which, for example, the trapezoidal attachment point 36 is arranged slightly below the trapezoidal attachment point 28 as seen in the z-direction. This ensures that, in the area of ​​maximum load, there is sufficient coverage between the eccentric device 10 and the connecting rod eye 5 for the entire adjustment range of the connecting rod device 1.

[0031] In the alternative embodiment of the connecting rod 3 according to the Fig. 4, the bevels 26, 27 preferably do not run symmetrically to the center plane 25. Preferably, the eccentric body 11 has a circumferential flange 41 against which the adjusting body 12 rests. The connecting rod 3 is preferably designed to receive the flange 41. For example, the flange 41 and the adjusting body 12 can each have a toothing that enables the transmission of an adjusting torque from the adjusting body 12 to the eccentric body 11. Preferably, the bevel 26 is a Fig. 4 shown on the left connecting rod side and the bevel 27 of a Fig. 4, the right connecting rod side shown on the right. A left trapezoidal attachment point 29' is assigned to the bevel 26, and a right trapezoidal attachment point 29 is assigned to the bevel 27. The position of the trapezoidal attachment points 29, 29' can be configured differently with respect to the z-direction due to the design of the eccentric body 11 with the flange 41.

[0032] The eccentric device 11 preferably has, analogous to the connecting rod 3, a left bevel 33 and a right bevel 34, which are particularly asymmetrical to the center plane 25. The left bevel 33 is assigned a left trapezoidal attachment point 36', and the right bevel 34 is assigned a right trapezoidal attachment point 36. The trapezoidal attachment points 36, 36' are preferably positioned differently with respect to the z-direction. The stepped design of the eccentric body 11 is particularly advantageous during assembly of the connecting rod device 1. With identical values ​​of the angles α and β for the left and right connecting rod sides, respectively, different trapezoidal attachment points 29, 29', 36, 36' result in the z-direction for the left and right connecting rod sides. When choosing identical trapezoidal attachment points, ie the position with respect to the z-direction of the trapezoidal attachment point 36' is the same as that of the trapezoidal attachment point 36 orthat of the trapezoidal attachment point 29' is equal to that of the trapezoidal attachment point 29, resulting in slight differences in the angles α, β with respect to the left and right connecting rod sides.

[0033] For example, Fig. 5 the eccentric device 10 in an end position of the minimum effective connecting rod length l eff_min . In this end position, the trapezoidal attachment points 29, 37 have, in particular, the same height in the z-direction. To transmit the maximum piston force to the connecting rod 3, the maximum bearing width a is always available with the connecting rod device 1 described. max or b max available. A contact pattern of the eccentric device 10 in the critical pressure range can thus never migrate into the connecting rod eye 5. Edge formation, as would be possible with a conventional trapezoidal design with identical attachment points of the connecting rod eye 5 and the eccentric device 10, can thus be reliably avoided. List of reference symbols 1 connecting rod device 2 pistons 3 connecting rod 4 Final section 5 connecting rod eye 6 Final section 7 crank bearing eye 8 Central axis 9 bearing shell 10 Eccentric device 11 Eccentric body 12 adjusting bodies 13 Linkage section 14 articulation section 15 Eccentric rod 16 Eccentric rod 17 Middle level 18 Central axis 19 Exterior area 20 interior surface 21 Piston pin bore 22 Central axis 23 piston pins 24 Arrow 25 Middle Level 26 slopes 27 slopes 28 Trapezoidal attachment point 29 Trapezoidal attachment point 30 final section 31 trapezoidal attachment line 32 trapezoidal approach line 33 slopes 34 slopes 35 groove 36 Trapezoidal attachment point 37 Trapezoidal attachment point 38 trapezoidal approach line 39 trapezoidal attachment line 40 final section 41 Flange a bearing width b bearing width c Width F Gas power l eff Effective connecting rod length max Maximum value of a size min Minimum value of a quantity α connecting rod eye angle section β Eccentric device angle section

Claims

[1] Adjustable connecting rod device (1) for an internal combustion engine with adjustable compression ratio, comprising: a connecting rod (3) with a connecting rod eye (5) which has, at least in sections, a circumferentially varying connecting rod eye bearing width (a) with a maximum connecting rod eye bearing width (a) extending circumferentially along a connecting rod eye angle section (α) max ), wherein the connecting rod eye angle section (α) is spanned between a first trapezoidal attachment point (28) of the connecting rod eye (5) and a second trapezoidal attachment point (29) of the connecting rod eye (5); an eccentric device (10) which is accommodated at least in sections in the connecting rod eye (5) and is adjustable relative thereto, which has an eccentric device bearing width (b) which is assigned to the connecting rod eye bearing width (a) and which varies at least in sections circumferentially, with a maximum eccentric device bearing width (b) which extends circumferentially along an eccentric device angle section (β) max ), wherein the eccentric device angle section (β) is spanned between a first trapezoidal attachment point (36) of the eccentric device (10) and a second trapezoidal attachment point (37) of the eccentric device (10); wherein the varying connecting rod eye bearing width (a) of the connecting rod eye (5) is interrupted over a width (c) by an adjusting body (12) of the eccentric device (10); wherein the eccentric device angle section (β) is provided larger than the connecting rod eye angle section (α), and wherein the eccentric device angle section (β) is selected such that when the eccentric device (10) is adjusted to end positions of a maximum effective connecting rod length (l eff_max ) or a minimum effective connecting rod length (l eff_min ) always completely covers the connecting rod eye angle section (α). [2] Adjustable connecting rod device according to claim 1, characterized by that the connecting rod eye angle section (α) corresponds to an effective angle section (α) of a maximum piston force. [3] Adjustable connecting rod device according to one of the preceding claims, characterized by that the maximum connecting rod bearing width (a max ) and the maximum eccentric bearing width (b max ) are the same size. [4] Adjustable connecting rod device according to one of the preceding claims, characterized bythat an end section (4) of the connecting rod (3) assigned to the connecting rod eye (5) has, at least in sections, a trapezoidal cross-section oriented approximately parallel to a central axis (18) of the connecting rod eye (5). [5] Adjustable connecting rod device according to claim 4, characterized by that the trapezoidal cross-section of the connecting rod (3) tapers towards an end section (30) of the connecting rod eye (5). [6] Adjustable connecting rod device according to one of the preceding claims, characterized by that the eccentric device (10) has an eccentric body (11) which is at least partially received in the connecting rod eye (5). [7] Adjustable connecting rod device according to claim 6, characterized by that the eccentric body (11) has, at least in sections, a trapezoidal cross-section oriented approximately parallel to a central axis (18) of the eccentric body (11). [8] Internal combustion engine with an adjustable connecting rod device (1) according to one of the preceding claims.

Images