Patent Publication Number: US-2022235680-A1

Title: Sealing arrangement

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     The present application claims priority to German Patent Application No. 10 2021 101 303.8 filed on Jan. 22, 2021. The entire contents of the above-listed application is hereby incorporated by reference for all purposes. 
     TECHNICAL FIELD 
     The present disclosure relates to a sealing arrangement for an internal combustion engine. 
     BACKGROUND 
     In internal combustion engines, the sealing of two adjacent parts of the oil pan assembly and the engine casing is important to prevent oil from leaking through a first interface between the two adjacent parts. Especially when a third part is attached to the two adjacent parts, a second interface must be sealed. When these three adjacent parts are joined together, further adequate sealing of a transition area located between the first and second interfaces may be required. 
     SUMMARY 
     U.S. Pat. No. 4,068,646 shows an oil pan comprising two separate sections each of which is secured independently to the engine as well as to each other, wherein a gasket is secured between the overlapping edges of sections and so as to provide an effective seal when the oil pan is installed under the engine block. It is suggested that the gasket is secured by passing a fastener through it. 
     Further, for large combustion engines such as found in V12 to V20 vehicles, molded seals specifically adapted to the parts to be sealed are generally used for the sealing between the oil pan and the engine casing parts. Such molded seals are however expensive to manufacture, especially in view of for large interfaces present in such engines. 
     The object of the present disclosure is therefore to provide an improved sealing solution. 
     The above-mentioned object of providing an improved sealing is solved by a sealing arrangement and/or a molded seal and/or an internal combustion engine. 
     The present disclosure provides a sealing arrangement for an internal combustion engine for sealing at least one interface of an oil pan assembly, comprising an O-ring for sealing a first interface between an upper edge portion of the oil pan assembly and a bottom side of an engine casing and at least one molded seal for sealing a second interface between two connectable parts of the engine. The O-ring extends in a plane formed by the first interface. The molded seal comprises two seal end portions comprising sealing areas to be sealingly connected to the O-ring. 
     Thus a simple and effective sealing solution is provided for sealing two interfaces. Further the sealing arrangement according to the disclosure provides a cost reduced solution due to its simple structure comprising an O-ring and at least one molded seal. 
     In an embodiment of the present disclosure, the second interface may transverse to the first interface, wherein the second interface can be orthogonal to the first interface and/or to a longitudinal direction of the engine. 
     In an embodiment of the present disclosure, the second interface is arranged vertically. 
     In an embodiment of the present disclosure, the O-ring has the same cross-section over its entire extension. 
     In an embodiment of the present disclosure, the sealing areas are provided on a front end side of the seal end portions and contact a side surface of the O-ring. In particular, the side surface of the O-ring contacted by the sealing area may be formed by one side of constant cross-section of the O-ring. 
     In an embodiment of the present disclosure, a groove is provided in the sealing surface of at least one seal end portion for retaining the O-ring. In particular, the groove may form a sealing area for sealing with the O-ring. 
     In an embodiment of the present disclosure, the groove is provided in a front end side of the seal end portion. 
     In an embodiment of the present disclosure, the O-ring is arranged in a first groove, which is provided in the upper edge portion of the oil pan assembly or in the bottom side of the engine casing. 
     In an embodiment of the present disclosure, the O-ring is arranged in a groove arrangement formed by the first groove and at least one second groove. 
     In an embodiment of the present disclosure, the second groove is arranged in a seal end portion of the molded seal. 
     In some embodiments, one or more sealing ribs protrude from a surface of the second groove towards the O-ring, wherein the one or more sealing ribs may be arranged transversely, such as orthogonally, to a longitudinal extension of the O-ring. 
     The arrangement of the O-ring in a groove provides a simple solution of holding the O-ring in place. In addition, the O-ring may not have to be manufactured in a certain shape, instead the O-ring may be produced shapeless so a so be adaptable to the specific shape of the first groove. 
     In an embodiment of the present disclosure, the O-ring is manufactured with the same cross-section over its entire extension. The cross-section may in particular be circular in the uncompressed state of the  0 -Ring. The O-ring may be formed by connecting the ends of a sealing cord. 
     By arranging the O-ring in a groove arrangement, the transition areas respectively being present between three connectable parts of the engine (for example two segments of the oil pan assembly and a crankcase of the engine casing) can be effectively and safely sealed. 
     The sealing ribs may increase local pressure when the O-ring is pressed against the molded seal, thus improving the sealing. The sealing ribs ensure a better interference between the O-ring and the molded seal. 
     In an embodiment of the present disclosure, an imaginary extension of a longitudinal extension of at least one molded seal does not cross with a second groove of the at least one molded seal. 
     In an embodiment of the present disclosure, an imaginary extension of a longitudinal extension of at least another one molded seal crosses with a second groove of the at least another one molded seal. 
     If the second groove is arranged such that it does not cross with a longitudinal extension of the molded seal, in a compressed state, which means when the O-ring is pressed against a surface of the second groove, a displacement of the molded seal may be avoided, since the seal end portion of the molded seal may be for the most part pressed against a blocking surface and/or against an enlarged retaining portion of a groove in which the molded seal may be arranged. 
     In an embodiment of the present disclosure, the molded seal is arranged in a groove provided in one of the surfaces forming the second interface. 
     In an embodiment of the present disclosure, the seal end portion is arranged in an enlarged retaining portion of the groove such that when the O-ring is pressed against the sealing area, a shoulder portion of the seal end portion is pressed against a surface of the enlarged retaining portion of the groove so as to block a displacement of the seal end portion. 
     In particular, the seal end portion, in which the second groove is provided, may be arranged in an enlarged retaining portion of the groove such that when the O-ring is pressed against a surface of the second groove, a shoulder portion of the seal end portion is pressed against a surface of the enlarged retaining portion of the groove so as to block a displacement of the seal end portion. 
     In an embodiment of the present disclosure, at least one molded seal comprises two seal end portions each having a sealing surface and a shoulder portion. 
     When the O-ring is pressed against the sealing surface of a respective seal end portion, the shoulder portion of the respective seal end portion is pressed against a retaining surface of a part of the engine, wherein the retaining surface may be formed in an enlarged retaining portion of a groove provided in one of the surfaces forming the second interface. 
     For instance, the retaining surface is formed in a crankcase of the engine and/or in a flywheel housing of the engine and/or in a front end of the engine casing. 
     In an embodiment of the present disclosure, the molded seal may contact a side of the O-ring facing away from the first groove. 
     For instance, both in a compressed and in an uncompressed state, the sealing surface of such a molded seal may be flat or convex. 
     In an embodiment of the present disclosure, the at least one seal end portion and/or the retaining surface for blocking the seal end portion is configured such that in a mounted state a portion of the seal end portion, a portion of the sealing surface facing the O-ring, such as a middle portion of the sealing surface, reaches into the first groove. 
     In an embodiment of the present disclosure, at least one molded seal with two seal end portions each having a second groove is provided. 
     For example, the molded seal with the second grooves is arranged between two segments of the oil pan assembly. 
     In an embodiment of the present disclosure, at least one molded seal with two seal end portions each having a sealing surface is arranged at a side of the O-ring facing away from the first groove. For instance, the sealing surfaces are flat or convex. In certain embodiments, the molded seal with the sealing surfaces is arranged between a crankcase and another part of the engine casing, such as a flywheel housing and/or a front end of the engine casing. 
     In an embodiment of the present disclosure, the O-ring consists of a flexible material and/or is shapelessly manufactured so as to be adaptable to a particular design of a first groove in which the O-ring is arranged. The first groove is provided in the upper edge portion of the oil pan assembly or in the bottom side of the engine casing. 
     In an embodiment of the present disclosure, the at least one molded seal is manufactured in a certain shape. 
     In an embodiment of the present disclosure, each molded seal is compressed by two adjacent surfaces of attachable parts of the engine. The two adjacent surfaces may be attached to each other by means of fasteners leading through interspaced openings provided in one or more flanges. The flanges are respectively rigidly connected to the respective adjacent surface. 
     In an embodiment of the present disclosure, the upper edge portion of the oil pan assembly presses the O-ring against the bottom side of the engine casing by means of fasteners leading through interspaced openings provided in one or more further flanges, which are respectively rigidly connected to the bottom side of the engine casing and/or the upper edge portion of the oil pan assembly. 
     In an embodiment of the present disclosure, at least one molded seal comprises one or more shoulder portions extending from the at least one molded seal transverse to its longitudinal extension for preventing a displacement in its longitudinal extension. 
     In an embodiment of the present disclosure, the at least one molded seal is arranged in a groove, wherein the groove is provided in one of two surfaces adjacent to and compressing the at least one molded seal. 
     In an embodiment of the present disclosure, at least one molded seal comprises at least one opening, such as with an  0 -shaped form, wherein an oil channel may lead through the respective opening. 
     In an embodiment of the present disclosure, the bottom side of the engine casing is formed by a bottom side of a crankcase of the engine casing and/or by a bottom side of a flywheel housing of the engine casing and/or by a bottom side of a front end of the engine casing. 
     Thus an improved sealing may be provided around an oil channel, which runs across two connectable parts of the engine. 
     In an embodiment of the present disclosure, the oil pan assembly comprises at least two segments, wherein between each two adjacent segments at least one molded seal is provided. In an upper edge portion of each segment a groove is provided such that the segments form a first groove in which the O-ring is arranged. For instance, each seal end portion of the molded seal provided between two adjacent segments may comprise a second groove in which the O-ring is arranged, thus the first groove and the second grooves may form a groove arrangement for the arrangement of the O-ring. 
     In an embodiment of the present disclosure, the sealing arrangement further comprises a third and/or a fourth molded seal. The third and/or the fourth molded seal each have two seal end portions respectively being connected to the O-ring so as to seal respective transition regions. The sealing surface of the seal end portions may be flat or convex in shape. 
     The third molded seal may be provided between a side surface of a crankcase of the engine casing and a side surface of a flywheel housing of the engine casing. 
     the fourth sealing may be provided between an other side surface of the crankcase and a side surface of a front end of the engine casing. 
     For instance, the third and/or the fourth molded seal may comprise at least one opening, such as with an O-shaped form, wherein an oil channel may lead through the respective opening. 
     For example, the third molded seal may be arranged in a third groove provided in the side surface of the crankcase or the side surface of the flywheel housing. The fourth molded seal may be arranged in a fourth groove provided in the other side surface of the crankcase or in the side surface of the front end. 
     In some embodiments, the third and/or the fourth molded seal contacts the O-ring at a position where it is retained in the first groove. Therefore, in particular, the interface sealed by the third and/or the fourth molded is provided at a different axial position than the interface sealed by the first molded seal. 
     In an embodiment the first interface extends in a single plane. 
     In an embodiment the second interface extends in a single plane. 
     In an embodiment, all the second interfaces sealed by molded seals of the sealing arrangement extends in a single plane. 
     In an embodiment, all the second interfaces sealed by molded seals are arranged in different axial positions along an axial direction of the engine. In particular, for an oil part assembly comprising at least two segments, an interface between the segments of the oil pan assembly will be provided at a position that is axially spaced apart from a position of an interface between two parts of the engine casing, such as an interface between a crankcase housing and flywheel housing or an interface between a crankcase housing and a front end housing. 
     The present disclosure further comprises a molded seal for a sealing arrangement, the molded seal comprising at least one seal end portion with a sealing surface, with a groove being provided in the sealing surface for retaining an O-ring. 
     For instance, the molded seal has the features already described above with respect to the sealing arrangement of the present disclosure. 
     Further, the molded seal may be part of the inventive sealing arrangement or used for an inventive sealing arrangement. 
     The present disclosure further comprises an internal combustion engine, comprising a sealing arrangement and/or comprising a molded seal as described above. 
     In an embodiment, the internal combustion engine comprises at least twelve cylinders and/or is a V-type engine. 
     In an embodiment, the oil pan assembly is a casted part and/or comprises at least two casted segments. 
     In an embodiment, the oil pan assembly has length of at least 1000 mm, wherein the length of the oil pan assembly corresponds to its extension in a longitudinal direction of the engine. The longitudinal direction of the engine corresponds to the extension of its crankshaft. 
     In an embodiment of the present disclosure, the engine casing is a crankcase, such that the upper edge portion of the oil pan assembly is attached to a bottom side of the crankcase. In an embodiment of the present disclosure, a crankshaft extends within the crankcase. 
     In an embodiment of the present disclosure, a rotational axis of the crankshaft extends at a level above the upper edge portion of the oil pan assembly forming the first interface to the engine housing. 
     In an embodiment of the present disclosure, the crankshaft is supported at at least two opposite end portions in the crankcase. 
     In an embodiment of the present disclosure, the crankshaft extends through at least one opening provided in a sidewall of the crankcase. A bottom side of the sidewall of the crankcase extending below the opening may be attached to an upper edge portion of the oil pan assembly. 
     In an embodiment of the present disclosure, the oil pan assembly and in particular the at least two segments of the oil pan assembly is/are attached to a bottom side of the crankcase. 
    
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
       The present disclosure will now be described with reference to embodiments and drawings. 
       The figures show: 
         FIG. 1  an isometric view of an embodiment comprising an oil pan assembly having two segments and a sealing arrangement, the embodiment being shown in a demounted state; 
         FIG. 2  an isometric view of the embodiment shown in  FIG. 1  in a state in which the two segments are attached to each other; 
         FIG. 3  a side view from the left of the embodiment shown in  FIG. 2 ; 
         FIG. 4 a    a front view of an embodiment comprising an oil pan assembly having two end segments and one middle segment; 
         FIG. 4 b    a front view of an embodiment comprising an oil pan assembly having two end segments and a middle segment being different to the middle segment of the embodiment shown in  FIG. 4   a;    
         FIG. 4 c    a front view of an embodiment comprising an oil pan assembly having two end segments being directly connected to each other; 
         FIG. 5  a front view of an embodiment comprising an oil pan assembly having two end segments; 
         FIG. 6  a front view of an embodiment comprising an oil pan assembly having two end segments, wherein the end segment on the left in  FIG. 6  is identical to the end segment shown on the left in  FIG. 5 ; 
         FIG. 7  an isometric view of an embodiment comprising a sealing arrangement having an O-ring and two molded seals; 
         FIG. 8  an isometric view of an embodiment comprising a sealing arrangement having an O-ring and three molded seals; 
         FIG. 9  an isometric, partly explosive view of an embodiment showing schematically an internal combustion engine comprising an oil pan assembly with two segments and comprising a sealing arrangement with an  0 -Ring and a molded seal; 
         FIG. 10  an isometric view of an embodiment comprising a sealing arrangement with an O-ring and a molded seal, the O-ring being arranged in a groove provided in the molded seal, wherein the sealing arrangement is shown separate from a casing; 
         FIG. 11  a side view from the left of the embodiment of the sealing arrangement shown in  FIG. 10 , wherein the sealing arrangement is arranged in a groove; 
         FIG. 12  an isometric view of an embodiment comprising a molded seal with a seal end portion having sealing ribs; 
         FIG. 13  a side view from the left of the embodiment shown in  FIG. 12 ; 
         FIG. 14  an isometric view of an embodiment comprising a molded seal having a sealing protrusion; 
         FIG. 15  a cross-sectional view of an embodiment comprising a molded seal for being arranged at a side of the O-ring facing away from a first groove in which the O-ring is arranged; and 
         FIG. 16  a front view of an embodiment comprising an oil pan assembly having two end segments, a crankcase, and a crankshaft leading through two openings provided in the crankcase. 
     
    
    
     DETAILED DESCRIPTION 
       FIG. 1  shows an embodiment of the present disclosure with an oil pan assembly  10  and a sealing arrangement  30 , wherein several aspects of the present disclosure are realized in combination. However, the features of these aspects described in the embodiment may also be realized separately. 
     According to a first aspect of the present disclosure an internal combustion engine  1  is provided having an oil pan assembly  10  which comprises at least two segments  20 , wherein the segments  20  are casted parts. 
     As can be seen in  FIG. 1  the oil pan assembly  10  comprises two segments  20  being two end segments  20   a , which respectively comprise an end wall  23   a , two side walls  23   b , and a bottom wall  23   c , the walls forming a part of the oil pan assembly  10 . As can be seen in  FIG. 4 a    and  FIG. 4 b    the oil pan assembly  10  may comprise a middle segment  20   b , which comprises a bottom wall  23   c  and two side walls  23   b  (only one of the two side walls  23   b  is respectively shown in  FIG. 4 a    and  FIG. 4 b   ). 
     The embodiment shown in  FIG. 1  comprises an oil pan assembly  10  with two segments  20 , wherein the embodiment is shown in a demounted state. The two segments  20  can be attached to each other at a second interface  71  and to a bottom side of an engine casing at a first interface  70  (not shown) by fasteners (not shown) which may lead through interspaced openings  24   c  provided in flanges  24 . In a mounted state, the segments  20  are attached to each other and to the underside of the engine thus compressing a sealing arrangement for sealing the respective interfaces between the parts. 
     In the embodiment shown in  FIG. 1 , the upper edge portion  11  of the oil pan assembly  10  is provided with a first groove  13  for receiving a sealing element for sealing the first interface  70  with the bottom side of an engine casing (not shown). One of the end faces  22  of the segments  20  is equally provided with a groove  29  receiving a sealing element for sealing the second interface  71  between the two segment end surfaces  22  of the segments  20 . 
     The two segments  20  of the embodiment shown in  FIG. 1  are casted parts, wherein the segments  20  are arranged next to each other in a longitudinal direction L of the engine (not shown). The longitudinal direction L of the engine corresponds to the axial extension of a crankshaft  2   a  (for example shown in  FIG. 16 ) of the engine. 
     In the embodiment shown in  FIG. 1  the segments  20  each comprise a segment end surface  22  being such configured that when the segments  20  are attached to each other the segment end surfaces  22  form the second interface  71  between the segments  20 . The second interface  71  shown in the embodiment extends in a plane which is orthogonal to the longitudinal direction L, wherein the first interface  70  between the upper edge portion  11  of the oil pan assembly  10  and the bottom side of the engine (not shown) is orthogonal to the second interface  71 . 
     As shown in  FIG. 1  each segment  20  may comprise a flange  24  that entirely surrounds the edge  25  of the respective segment  20 . Further also a middle segment  20   b , as shown in  FIG. 4 a   , may comprise a flange  24  that entirely surrounds the middle segment  20   b.    
     In the embodiment shown in  FIG. 1  each of the segments  20  comprises a stiffening rib  14 , wherein the configuration of the stiffening ribs  14  is exemplarily described regarding the stiffening rib  14  of the segment  20  shown on the right in  FIG. 1 . The stiffening rib  14  extends from a side wall  23   b  to a bottom wall  23   c  of the segment  20 . Further the stiffening rib  14  extends from the bottom wall  23   c  to the other side wall  23   b.    
     As can be seen in the embodiment shown in  FIG. 1  the stiffening rib  14  comprises at least one opening  14   a , which allows an oil exchange between an area at one side to an area at another side of the stiffening rib  14 . For providing the opening, the stiffening rib  14  does not contact the bottom wall  23   c  over the entire width of the segment, such that an opening  14   a  is left between the bottom wall  23   c  and a lower edge of the stiffening rib  14  in this area. In the embodiment, openings  14   a  are provided on both sides of a middle portion  14   c  of the stiffening rib  14  connected to the bottom wall. 
     In the shown embodiment the stiffening rib  14  comprises a side portion  14   b  which is arranged closer to the side wall  23   b  than the middle portion  14   c , wherein an upper edge of the side portion  14   b  reaches closer to the first interface  70  than an upper edge of the middle portion  14   c . The same applies to the other side portion (not shown) of the sealing rib  14 . 
       FIG. 2  shows the embodiment of  FIG. 1  in a state, in which the segments  20  are attached to each other, wherein the oil pan assembly  10  forms an upper edge portion  11 , which is formed by the segment upper edge portions  21 . 
     The embodiment shown in  FIG. 2  comprises several openings  26 ,  27 , wherein the opening  26  provided in the oil pan assembly  10  is arranged closer to the bottom wall  23   c  than the other openings  27 . The openings  26 ,  27  allow an oil exchange between an inside and an outside area of the oil pan assembly. As can be seen, the openings  26 ,  27  may have different diameters, in order to satisfy different application purposes. 
     An oil pump may be connected to the mounting area surrounding opening  27 , with a suction side oil channel of the pump reaching through opening  27  into the oil pan assembly. 
       FIG. 3  shows a side view from the left of the embodiment shown in  FIG. 2 , wherein the end segment  20   a  comprises a flange  24  that entirely surrounds the end segment  20   a  and that extends in two planes that are orthogonal to each other. One of the planes forms the second interface  71 , as can be seen in  FIG. 2 . The other plane forms the first interface  70 , as can be seen in  FIG. 2  and  FIG. 3 . The flange  24  shown in  FIG. 3  comprises an upper flange surface  24   a  which forms a flat upper surface  15  of the oil pan assembly  10 . 
     In the embodiment shown in  FIG. 2  and  FIG. 3 , each end segment  20   a  comprises a plurality of leg portions  28 , which may be integrally casted with the respective end segment  20   a . As can be seen in  FIG. 2  and  FIG. 3  a portion of the flange  24  may form a leg portion  28 . 
     As can be seen in  FIG. 3 , the end segment  20   a  may be such configured that when it is being placed on a flat surface, the leg portions  28  contact the flat surface to support the segment, wherein at least a part of the bottom wall  23   c  of the end segment  20   a  is spaced apart from the flat surface. In an embodiment, also a middle segment  20   b , as for example shown in  FIGS. 4 a  and 4 b   , may comprise the above described configuration regarding the leg portions  28 . 
     In the embodiment, all the segments have the same height H. In particular, the distance between the bottom side of the leg portions  28  and the upper edge portion  21  of each segment  20  may be identical. 
     As can be seen in  FIG. 2  and  FIG. 3 , the segments  20  may comprise stiffening ribs provided between the flange  24  and a wall, such as an outer side of a wall, of the respective segment  20 . 
     The surfaces of the segments forming the interfaces, and in particular the segment upper edge portions  21 , the segment end surfaces  22  and the grooves  13  and  29  can be formed by material removal from the casted part. In particular, the surface may be formed by milling. 
     According to a second aspect of the present disclosure a set comprising at least two different internal combustion engines each comprising an oil pan assembly is provided. With the following described modular concept a set of engines with oil pan assemblies is proposed, wherein each oil pan assembly is adapted to a particular size of engine, wherein the oil pan assemblies have at least one segment in common. The oil pan assemblies may in particular be adapted to different lengths of the engine which are due to a difference in the number of cylinders of the engine, wherein the different engines may have between 12 and 20 cylinders, inclusive. 
     The embodiment of a set shown in  FIGS. 4 a , 4 b , and 4 c    comprises three different engines (not shown) each having an oil pan assembly  10 . Each of the shown oil pan assemblies  10  comprises two end segments  20   a , wherein the end segments  20   a  of the oil pan assembly  10  shown in  FIG. 4 a    are identical to the end segments  20   a  of the oil pan assemblies  10  shown in  FIGS. 4 b  and 4 c   . The end segments  20   a  shown in  FIG. 4 c    are attached to each other directly. Regarding  FIG. 4 b    a middle segment  20   b  is arranged between the two end segments  20   b , wherein the segments  20   a ,  20   b  are connected to each other respectively. A further modification is possible, as can be seen  FIG. 4 a   , in which a middle segment  20   b  of a different length than that shown in  FIG. 4 b    is arranged between the two end segments  20   a . Thus a set of three different oil pan assemblies with three different lengths can be provided with only four different segments (end segment  20   a  shown on the left in  FIG. 4 a   , end segment  20   a  shown on the right in  FIG. 4 a   , middle segment  20   b  shown in  FIG. 4 a   , and middle segment  20   b  shown in  FIG. 4 b   ). 
     In another embodiment, as for example shown in  FIGS. 5 and 6 , it is also conceivable to provide a set comprising at least two different internal combustion engines (not shown), wherein the engines respectively comprise a first identical end segment  20   a , in  FIGS. 5 and 6  the respective end segment  20   a  on the left, wherein the engines further comprise respectively a second end segment  20   a , in  FIGS. 5 and 6  the respective end segment  20   a  on the right, being (directly) connected to the first end segment  20   a , wherein the second end segments  20   a  of the engines are different, and for instance, have different lengths, as can be seen in  FIGS. 5 and 6 . 
     In the embodiment shown in  FIG. 4 a   , the edge  25  of the middle segment  20   b  is formed by a flange  24 , wherein the flange  24  entirely surrounds the edge  25  of the middle segment  20   b.    
     The height H of a segment  20   a ,  20   b  is defined as its extension from its bottom side  12  to its upper surface  15 , as shown in  FIG. 4 a   . The segments  20   a ,  20   b  of the embodiment shown in  FIG. 4 a    each comprise the same height H. The same applies to the segments of the embodiments shown in  FIGS. 4 b  and 4 c   ,  FIG. 5  and  FIG. 6 . As can be seen from  FIGS. 4 a  to 4 c    the embodiments each comprise segments  20   a ,  20   b  having an equal height H. 
     The length of the oil pan assembly  10  is defined as its extension in a direction parallel to the longitudinal direction L of the engine, as can be seen in  FIGS. 4 a  to 4 c    and in  FIGS. 5 and 6 . In other words the length of an oil pan assembly  10  is defined as its extension from an outer end of an end segment  20   a  (in  FIGS. 4 a  to 4 c    on the left) to an outer end of the other end segment  20   a  (in  FIGS. 4 a  to 4 c    respectively on the right). 
     The embodiment of the set shown in  FIGS. 4 a  to 4 c    comprises three different oil pan assemblies  10  having different lengths, thus the respective oil pan assembly  10  being designed for a particular engine size. The embodiment of the set shown in  FIGS. 5 to 6  comprises two different oil pan assemblies  10  having different lengths, thus the respective oil pan assembly  10  being designed for a particular engine size. 
     For example the oil pan assembly  10  shown in  FIG. 4 a , 4 b , 4 c    may be designed for an engine having  20 ,  16 ,  12  cylinders, respectively, wherein the respective engine can be a V-type engine. 
     In the embodiment shown in  FIG. 4 a    the oil pan assembly  10  comprises a length greater than 2000 mm and/or is designed for an engine having 20 cylinders. 
     In the embodiment shown in  FIG. 4 b    the oil pan assembly  10  comprises a length greater than 1500 mm and/or is designed for an engine having 16 cylinders. 
     In the embodiment shown in  FIG. 4 c    the oil pan assembly  10  comprises a length greater than 1000 mm and/or is designed for an engine having 12 cylinders. 
     In an embodiment the internal combustion engine  1  comprising the sealing arrangement  30  and/or the oil pan assembly  10  may be a V-type engine and/or comprises more than 12 cylinders. 
     Regarding the embodiment shown in  FIGS. 4 a  and 4 b    a first and a second molded seal  40   a ,  40   b  may be provided between the end segment  20   a  shown on the left and the middle segment  20   b  and between the middle segment  20   b  and the end segment  20   a  shown on the right, respectively. Regarding the embodiment shown in  FIGS. 5 and 6 , a first molded seal (not shown) may respectively be provided between the end segments  20   a.    
     The oil pan assemblies described with respect to the second aspect of the present disclosure may have the configuration already described with respect to the first aspect. 
     In particular, in the embodiment, the end segments  20  of the oil pan assembly shown in  FIGS. 1 to 3  are used as the end segments  20   a  of the oil pan assemblies shown in  FIGS. 4 a  to 4 c   . Therefore, the oil pan assembly shown in  FIG. 4 c    is the same oil pan assembly already described with respect to  FIGS. 1 to 3 . 
     As shown in  FIG. 16 , the internal combustion engine may comprise a crankshaft  2   a , the rotational axis of which extends at a level above the first interface  70  between the upper edge portion  11  of the oil pan assembly  10  and the engine casing. 
     In the embodiment, the rotational axis of the crankshaft  2   a  extends above the level of the upper edge portion  11  of the oil pan assembly through a crankcase forming the engine housing, the bottom side of which is attached to the upper edge portion  11  of the oil pan assembly. In particular, the at least two segments  20 ,  21  of the oil pan assembly may be attached to a bottom side of a crankcase  2 . 
     The crankcase  2  supports the crankshaft  2   a  at two opposite end portions of the crankshaft  2   a.    
     At least one end of the crankshaft  2   a  extends through an opening provided in the crankcase  2 . In the shown embodiment, the crankshaft  2   a  extends through a first opening provided in a first sidewall of the crankcase  2  and/or extends through a second opening provided in a second, opposed sidewall of the crankcase  2 . Lower edge portions of the first and/or second sidewalls may be sealingly connected to upper edge portions  11  of the oil pan assembly. 
     According to a third aspect of the present disclosure, a sealing arrangement  30  may be provided having an O-ring  31  and at least one molded seal  40 . 
     The O-ring  31  consists of a flexible material and/or is shapelessly manufactured. It can therefore be adapted to a certain shape of a first groove  13 . 
     The O-ring has the same cross-section over its entire extension and forms a closed loop. It may for example be provided by connecting two ends of a sealing cord. The cross-section may be circular when the O-ring is uncompressed. 
     The molded seal ( 40 ) comprises two seal end portions ( 41 ) comprising sealing areas ( 48 ) to be sealingly connected to the O-ring ( 31 ). In particular, the sealing areas ( 48 ) are provided on a front end side of the seal end portions ( 41 ) and contact a side surface of the O-ring. 
     The embodiment shown in  FIG. 7  comprises a sealing arrangement  30  having an O-ring  31 , a third molded seal  40   c , and a fourth molded seal  40   d . The O-ring  31  is provided for sealing a first interface between an upper edge portion (not shown) of an oil pan assembly and a bottom side (not shown) of an engine casing. 
     The molded seals  40   c ,  40   d  respectively comprise two seal end portions  41 , which are respectively sealingly connected to the O-ring  31 . 
     In the shown embodiment the molded seal  40   c  is provided for sealing an interface between a crankcase (not shown) and a flywheel housing (not shown), wherein the molded seal  40   c  can be arranged in a groove provided in the flywheel housing or the crankcase housing. The molded seal  40   d  is provided for sealing an interface between the crankcase housing and a front end housing (not shown) of the engine, wherein the molded seal  40   d  may be arranged in a groove provided in the front end housing or the crankcase housing. 
     As shown in  FIG. 7  the molded seal  40   d  may comprise two openings  52  for allowing an oil channel to pass through. 
     The seal end portions  41  of the third and the fourth molded seal  40   c ,  40   d  shown in  FIG. 7  can be of the type shown in  FIGS. 14 and 15 , wherein the O-ring  31  may be arranged in a first groove  13  of an oil pan assembly. The molded seals  40   c ,  40   d  may contact a side of the O-ring, which faces away from the first groove. 
     In the embodiment shown in  FIG. 7  the O-ring  31  extends in a single plane, wherein the molded seals  40   c ,  40   d  extend transversally thereto. 
     Further, in the shown embodiment the sealing arrangement  30  may be provided for an oil pan assembly (not shown) being made out of one part. 
     The embodiment shown in  FIG. 8  comprises a sealing arrangement  30  having a first molded seal  40   a , a third molded seal  40   c , and a fourth molded seal  40   c . In the shown embodiment the first molded seal  40   a  is provided for sealing a second interface between two segments (not shown) of an oil pan assembly  10 , the second interface  71  therefore being a segment interface  71 . The molded seal  40   a  extends in a plane which may be orthogonal to the first interface  70 , as shown in  FIG. 8 , wherein the O-ring  31  extends in the first interface  70 . The third and fourth molded seals  40   c ,  40   d  extend respectively in further second interfaces  71 . 
     Each of the molded seals  40   a ,  40   c , and  40   d  shown in  FIG. 8  comprises two seal end portions  41 . 
     The two seal end portions  41  of the first molded seal  40   a  may be of the type shown in  FIGS. 10 to 13 , wherein the seal end portions  41  of the third and fourth molded seal  40   c ,  40   d  may be of the type shown in  FIGS. 14 and 15 . 
     In the embodiment shown in  FIGS. 7 and 8  the first groove (not shown) can be provided in an upper edge portion of an oil pan assembly (not shown). 
     In the embodiment shown in  FIGS. 7 and 8 , such as the molded seals  40   a ,  40   c ,  40   d , are respectively manufactured in a certain shape. 
     In the embodiment shown in  FIG. 9 , an internal combustion engine  1  is shown schematically. The embodiment is shown in a demounted state. The engine  1  comprises an oil pan assembly, wherein only small portions of two segments  20  are illustrated, and a sealing arrangement, wherein only small portions of the molded seal  40  and the O-ring  31  are illustrated. In the shown embodiment the engine casing  1   a  comprises a bottom side  1   b , which is formed by a bottom side of a crankcase  2 , by a bottom side of a front end  3 , and/or by a bottom side of a flywheel housing  4 . In  FIG. 9  the crankcase  2 , the front end  3 , and the flywheel housing  4  are illustrated schematically. 
     In the embodiment shown in  FIG. 9  the O-ring  31  is arranged in the first groove  13  which is provided in the upper edge portion  11  of the oil pan assembly (which is in particular formed by the segment upper edge portions  21 ), wherein the O-ring  31  is provided for sealing the first interface  70  between the upper edge portion  11  and the bottom side  1   b  of the engine casing  1   a.    
     The first molded seal  40   a  is sealingly connected to the O-ring  31  and extends between the two segments  20  so as to seal the second interface  71  which is formed there between. 
     In an embodiment, the seal end portion  41  of the first molded seal  40   a  between two segments  20 , as shown in  FIG. 9 , may comprise a seal end portion  41  with a second groove  42 , as for example shown in  FIGS. 10 to 13 , in which the O-ring  31  can be arranged. Thus the first groove  13  and the second groove  42  may form a continuous groove  13 , 42  for the O-ring  31 , the continuous groove  13 , 42  being a groove arrangement  13 , 42 . 
     When the segments  20  shown in the embodiment of  FIG. 9  are attached to each other and to the underside  1   b  of the engine casing la, such as by using fasteners leading through openings provided in the shown flanges  24 , the O-ring  31  and the first molded seal  40   a  are compressed by respective adjacent surfaces so as so seal the respective interfaces  70 ,  71 . 
     According to a fourth aspect of the present disclosure a molded seal  40  for the sealing arrangement  30  comprises a groove for retaining the O-ring  31 . 
     According to the embodiments shown in  FIGS. 10 to 13  a sealing arrangement  30  is provided for sealing a transition region between at least three connectable parts of an internal combustion engine. The shown embodiments of the sealing arrangement  30  may be provided for sealing the transition region being present between two segments of an oil pan assembly and an a bottom side of an engine casing, as described with respect to the third aspect. 
     The O-ring  31  shown in the embodiment illustrated in  FIG. 10  has a longitudinal extension L 1  and is arranged in the second groove  42 , which is provided in the seal end portion  41  of the molded seal  40 . The molded seal  40  may be a first molded seal  40   a  for sealing an interface between two segments of an oil pan assembly (not shown). In the shown embodiment the molded seal  40  comprises a longitudinal extension L 2 , which runs vertically in the drawing plane of  FIG. 10 . 
     As shown, the molded seal  40  may comprise a retaining portion  46  that protrudes from the molded seal  40  transverse to its longitudinal extension L 2 . Thus a displacement of the molded seal  40  may be blocked, when the O-ring  31  is pressed towards the seal end portion  41 . 
     The embodiment shown in  FIG. 11  comprises a sealing arrangement  30  being identical to the one shown in  FIG. 10 , wherein in  FIG. 11  the molded seal  40  is arranged in the groove  29  with the seal end portion  41  of the molded seal  40  being arranged in an enlarged retaining portion  29   a  of the groove  29 . 
     The seal end portion  41  is formed by an enlarged shoulder portion  45  retained in the enlarged retaining portion  29   a  of the groove  29 . In particular, the enlarged retaining portion  29   a  of the groove  29  may extend perpendicular to the longitudinal extension of the molded seal L 2  and the O-ring L 1  along an edge formed between the first and the second interface. The enlarged shoulder portion  45  of the molded seal may extend within the enlarged retaining portion  29   a , such that retaining surfaces  29 b formed by the bottom of the enlarged retaining portion  29   a  retain bottom surfaces  45 a of the enlarged shoulder portion  45  on both sides of the molded seal. 
     When the O-ring  31  is pressed against the surface  43  of the second groove  42  provided in the seal end portion  41 , the shoulder portion extending in the enlarged retaining portion  29   a  blocks a displacement of the seal end portion  41 . 
     In the embodiment shown in  FIG. 11  the seal end portion  41  comprises a sealing area  48  formed by the second groove  42 . 
     The O-ring  31  is arranged in the second groove  42  and a first groove  13 , wherein the first groove  13  is provided in the segment upper edge portion  21  of the segment  20 . The O-ring is therefore arranged in a groove arrangement  13 ,  42 , which is formed by the first groove  13  and the second groove  42 . In other words, the first groove  13  and the second groove  42  may form a continuous groove  13 ,  42  in which the O-ring  31  can be arranged. 
     The molded seal  40  can be provided between two segments  20  of the oil pan assembly  10 , wherein in  FIG. 11  only one of the two segments  20  is partly shown. In the shown embodiment the groove  29  with its enlarged retaining portion  29   a  is formed in the segment  20 , more precisely in an segment end surface  22 . As shown in  FIG. 11 , the segment  20  comprises a segment upper edge portion  21  which forms a flat upper surface  15  of the oil pan assembly (not shown). 
     In an alternative embodiment a sealing arrangement  30  with a molded seal  40  having a second groove  42  provided in its seal end portion  41  for retaining an O-ring  31  may be arranged between a crankcase of the engine and another part of the engine casing connectable thereto, wherein a first groove  31  for retaining the O-ring  31  can be formed in a bottom side of the engine casing. 
     In the embodiment shown  FIG. 11  the second groove  42  is such arranged in the seal end portion  41 , that an imaginary extension of the longitudinal extension L 2  of the molded seal  40  (more precisely the axial center line of the longitudinal extension L 2  of the molded seal  40 ) does not cross with the second groove  42 . 
     In other words, the center of the second groove  42  is arranged at a distance to an imaginary extension of a side wall  22  of the groove  29  and therefore at a position above a bottom surface of the enlarged retaining portion  29   a  of the groove. 
     In this case, when the O-ring  31  is pressed against a surface  43  of the second groove  42 , the bottom side of the shoulder portion  45  of the seal end portion  41  is pressed against a bottom surface of the enlarged retaining portion  29   a  of the groove. Thus a displacement of the seal end portion  41  is blocked. 
     In an alternative embodiment, the second groove  42  may be arranged in the seal end portion  41  such that an imaginary extension of the longitudinal extension L 2  of the molded seal  40  (more precisely the axial center line of the longitudinal extension L 2  of the molded seal  40 ) crosses with the second groove  42 . 
     It is also conceivable to provide an embodiment of a molded seal having one seal end portion  41  with a second groove  42  being arranged such that it does not cross with the imaginary extension of the longitudinal extension L 2  of the respective molded seal  40 , and having another seal end portion  41  with another second groove  42  being arranged such that it does cross with the imaginary extension of the longitudinal extension L 2  of the molded seal  40 . 
     The embodiment shown in  FIG. 12  and  FIG. 13  illustrates a molded seal  40  having a seal end portion  41  comprising three sealing ribs  44 . The molded seal  40  shown in  FIG. 12  and in  FIG. 13  is identical to the one shown in  FIG. 10  and  FIG. 11 . As shown in  FIG. 12  and  FIG. 13 , the sealing ribs  44  protrude from a surface  43  of the second groove  42  and may reach from one side of the sealing surface  47  of the seal end portion  41  over the surface  43  of the second groove  42  to the other side of the sealing surface  47 . In the shown embodiment the sealing ribs  44  extend orthogonally to a longitudinal extension L 1  of the O-ring  31  (not shown). 
     As can be seen in  FIG. 11 , the O-ring  31  may be pressed, such as by a bottom side of an engine casing (not shown), against the sealing ribs  44  such that O-ring  31  compresses the sealing ribs  44  towards the surface  43  of the second groove  42 . Thus an enhanced sealing can be provided. 
       FIGS. 14 and 15  illustrate an embodiment of a molded seal  40 , which may be provided between a side surface of a crankcase (not shown) and another side surface of a part of the engine casing connectable to the crankcase. Referring to  FIG. 9 , the molded seal  40  shown in  FIG. 14  may be provided between the crankcase  2  and the flywheel housing  4  and/or between the crankcase  2  and the front end  3 , wherein the molded seal  40  shown in  FIGS. 14 and 15  may be provided at a side of the O-ring  31  facing away from the first groove  13 . 
     As illustrated in  FIG. 14 , the seal end portion  41  of the molded seal  40  equally comprises an enlarged shoulder portion, which is retained in an enlarged retaining portion of a groove in the same way as the enlarged shoulder portion of the embodiments of the molded seal described earlier. 
     As shown in  FIG. 15 , the sealing surface  50  of the molded seal  40  is pressed against an O-ring  31  arranged in a first groove  13 . In the shown embodiment the first groove  13  is provided in an upper edge portion  11  of an oil pan assembly (not shown). 
     As can be seen in  FIG. 14 , the sealing surface  50  of the molded seal  40  has a flat shape and extends in a single plane when the seal is uncompressed. In alternative embodiments, if might also have a convex shape, for example a middle portion protruding from the sealing surface. 
     In  FIG. 15  the sealing arrangement  30  is shown in a mounted state, the sealing arrangement  30  therefore being in a compressed state, which means that the upper edge portion  11  of the oil pan assembly (not shown) presses the O-ring  31  against the sealing surface  50  of the molded seal  40 . 
     The seal end portion  41  shown in  FIG. 15  is such configured that in the shown mounted state a portion of the seal end portion  41  reaches into the first groove  13 . More precisely, the middle portion  50   b  of the sealing surface  50  of the seal end portion  41  reaches into the first groove  13 . With the shown embodiment it is possible that the sealing surface  50  adapts its shape at least partially to the O-ring. The sealing between the O-ring  31  and the molded seal  40  can be enhanced consequently. As can be seen in  FIG. 15  the middle portion  50   b  is arranged between two side portions  50   a  of the sealing surface  50 . 
     Further  FIG. 15  illustrates that the seal end portion  41  of the molded seal  40  may be such configured that the side portions  50   a  of the sealing surface  50 , in a mounted state, are pressed against respective surfaces of the upper edge portion  11 , which are respectively arranged adjacent to the surface of the first groove  13 , which means that the surfaces are arranged at one and on another side of the first groove  13 , in  FIG. 15  to the left and to the right of the first groove  13 , respectively. 
     Subsequently, in a mounted state, beside the sealing between the O-ring  31  and the middle portion  50   b  of the sealing surface  50 , at least another sealing can be provided between the respective side portions  50   a  of the sealing surface  50  and the respective surface of the upper edge portion  11 . In the shown embodiment of  FIG. 15  three sealing areas are provided: between the O-ring  31  and the middle portion  50   b  of the sealing surface  50 , between one side portion  50   a  (in  FIG. 15  on the left) of the sealing surface  50  and the respective surface of the upper edge portion  11 , and between the other side portion  50   a  (in  FIG. 15  on the right) of the sealing surface  50  and the respective surface of the upper edge portion  11 . 
     Referring to  FIG. 15 , the retaining surface  60  of the enlarged retaining portion of the groove in which the molded seal  40  is provided blocks the shoulder surface  54  of the enlarged shoulder portion of the seal end portion  40 . The retaining surface  60  may comprise an outer portion  60   a  and an inner portion  60   b , wherein the inner portion  60   b  is arranged closer to a center axis of the longitudinal extension L 2  of the molded seal  40  than the outer portion  60   a , wherein the inner portion  60   b  may extend closer to the bottom side of the engine casing than the outer portion  60   a . Subsequently the effect of at least a part of the seal end portion  41 , such as the middle portion  50   b , reaching into the first groove  13  in a mounted stated can be enhanced. 
     In the embodiment shown in  FIG. 15  the seal end portion  41  comprises sealing areas  48 , which are formed by the middle portion  50   b  and respective side portions  50   a  of the sealing surface  50 . 
     As described above, the molded seal  40  shown in  FIG. 15  may be arranged in a groove  29 , wherein the seal end portion  41  may be provided in a enlarged retaining portion  29   a  of the groove  29 . Referring to  FIG. 9 , the groove  29  may be provided in the front end  3 , the crankcase  2  and/or the flywheel housing  4  of the engine casing la, the groove  29  may however be provided in the front end and/or the flywheel housing  4 . In the embodiment shown in  FIG. 15  the enlarged retaining portion  29   a  of the groove  29  forms the retaining surface  60  for blocking the seal end portion  41 . 
     As shown in  FIG. 14 , the seal end portion  41  may be provided on a side surface facing the groove  29  and/or the side surface facing the other engine part with a sealing protrusion  53 . The sealing protrusion  53  may protrude from a side surface  41 a of the seal end portion  41  in a direction transverse to the longitudinal extension L 2  of the molded seal  40 , wherein the sealing protrusion  53  may extend from one side portion  50   a  of the sealing surface  50  to the respective other side portion  50   a  of the sealing surface  50 , such as in a U-shaped form. 
     The configuration of the sealing arrangement shown in  FIGS. 10 to 14  may in particular be used with the sealing arrangements described with respect to  FIGS. 7 to 9 . 
     Further, the sealing arrangements described with respect to  FIGS. 8 to 14  may in particular be used with the oil pan assemblies described with respect to  FIGS. 1 to 6 . 
     The sealing arrangement described with respect to  FIG. 7  may be used with an oil pan assembly where the oil pan is a single casted part. 
       FIGS. 1-6  are drawn to scale, although other relative dimensions may be used. 
     The figures show example configurations with relative positioning of the various components. If shown directly contacting each other, or directly coupled, then such elements may be referred to as directly contacting or directly coupled, respectively, at least in one example. Similarly, elements shown contiguous or adjacent to one another may be contiguous or adjacent to each other, respectively, at least in one example. As an example, components laying in face-sharing contact with each other may be referred to as in face-sharing contact. As another example, elements positioned apart from each other with only a space there-between and no other components may be referred to as such, in at least one example. As yet another example, elements shown above/below one another, at opposite sides to one another, or to the left/right of one another may be referred to as such, relative to one another. Further, as shown in the figures, a topmost element or point of element may be referred to as a “top” of the component and a bottommost element or point of the element may be referred to as a “bottom” of the component, in at least one example. As used herein, top/bottom, upper/lower, above/below, may be relative to a vertical axis of the figures and used to describe positioning of elements of the figures relative to one another. As such, elements shown above other elements are positioned vertically above the other elements, in one example. As yet another example, shapes of the elements depicted within the figures may be referred to as having those shapes (e.g., such as being circular, straight, planar, curved, rounded, chamfered, angled, or the like). Further, elements shown intersecting one another may be referred to as intersecting elements or intersecting one another, in at least one example. Further still, an element shown within another element or shown outside of another element may be referred as such, in one example. 
     REFERENCE SIGN LIST 
     
         
           1  internal combustion engine 
           1   a  engine casing 
           1   b  bottom side of engine casing 
           2  crankcase 
           2   a  crankshaft 
           3  front end 
           4  flywheel housing 
           10  oil pan assembly 
           11  upper edge portion 
           12  bottom side of oil plan assembly /segment 
           13  first groove 
           14  stiffening rib 
           14   a  opening of stiffening rib 
           14   b  side portion of stiffening rib 
           14   c  middle portion of stiffening rib 
           15  flat upper surface 
           20  segment 
           20   a  end segment 
           20   b  middle segment 
           21  segment upper edge portion 
           22  segment end surface 
           23   a  end wall 
           23   b  side wall 
           23   c  bottom wall 
           24  flange 
           24   a  upper flange surface 
           24   b  flange end surface 
           24   c  openings provided in the flange 
           25  edge 
           26  opening 
           27  opening 
           28  leg 
           29  groove 
           29   a  enlarged retaining portion of groove 
           30  sealing arrangement 
           31  O-ring 
           40  molded seal 
           40   a  first molded seal 
           40   b  second molded seal 
           40   c  third molded seal 
           40   d  fourth molded seal 
           41  seal end portion 
           41   a  side surface of seal end portion 
           42  second groove 
           43  surface of second groove 
           44  sealing rib 
           45  shoulder portion 
           46  retaining portion of molded seal 
           47  sealing surface of a molded seal being arranged at a side of the O-ring facing the first groove 
           48  sealing area of seal end portion 
           50  sealing surface of a molded seal being arranged at a side of the O-ring facing away from the first groove 
           50   a  side portion of sealing surface 
           50   b  middle portion of sealing surface 
           52  opening for oil channel 
           53  sealing protrusion 
           54  retaining surface 
           60  blocking surface 
           60   a  outer portion of blocking surface 
           60   b  inner portion of blocking surface 
           70  first interface 
           71  second interface, segment interface 
         L longitudinal direction of the engine 
         L 1  Longitudinal extension of O-ring 
         L 2  Longitudinal extension of molded seal 
         H segment height