Oilsump Assembly, Internal Combustion Engine, Vehicle, and Method

The invention relates to an oil sump assembly connectable to an internal combustion engine, comprising an oil reservoir with an opening for collecting oil from the internal combustion engine. The invention further relates to an internal combustion engine comprising such an oil sump assembly. The invention further relates to a vehicle, e.g. a truck, that comprises such an internal combustion engine. The invention further relates to a method for assembling the oil sump assembly, e.g. to the internal combustion engine.

An oil sump, also known as an oil pan, is usually used in an internal combustion engine to provide a reservoir for engine oil that is used to lubricate the moving parts of the engine, such as the crankshaft and pistons. The oil sump is normally bolted to the bottom of the engine block, sealing the bottom of the engine to prevent oil leaks. It also provides a barrier that protects the oil and internal components from dirt and debris.

Oil sumps may come in various shapes and sizes to match the engine design. In order to limit vibrations, and thus sound production, the oil sump may be elastically suspended instead of directly mounted to the engine block, e.g. in a so-called “floating suspension”. To prevent leakages, such a floating oil sump design is generally only possible if the sump and a corresponding gasket are clamped onto the engine.

However, considering the limited space that is available around and below an engine block, it is a challenge to provide a leak-proof floating oil sump arrangement that is easy to assemble and install. The shape of the cylinder block generally determines the outside contour of the oil sump and corresponding gasket. Hence there is limited design freedom for a floating oil sump. Using auxiliary mounting elements may allow a more flexible design of the oil sump, yet at the cost of decreased ease of assembly. Furthermore, using auxiliary mounting elements may lead to incorrect assembly of the oil sump gasket due to the low controllability of the assembly, with potential leakages as a result.

It is an object of the present invention to provide a floating oil sump assembly that can be assembled in an easy and controllable fashion.

Aspects of the invention therefore relate to an oil sump assembly as defined in the appended claims. The oil sump assembly is connectable to an internal combustion engine and comprises an oil reservoir with an opening for collecting oil from the internal combustion engine. The oil reservoir may be made of steel, aluminium, or any other type of (composite) material. The oil reservoir is provided with a flange that extends around the opening and is arranged for circumferentially mounting to an engine mounting surface.

The oil sump assembly comprises a framework arranged for interconnecting the flange and the engine mounting surface. The framework comprises a first frame part and a second frame part. The first frame part circumferentially extends around the opening on a first side of the flange, and provides an interface between the flange and the engine mounting surface. The second frame part is provided on a second side of the flange opposite the first side, and is removably fixated to the first frame part by an internal fixation arrangement.

A recess is formed between the first and second frame part. The flange extends into the recess and is sandwiched between sidewalls of the recess by a first gasket that covers the first and second side of the flange. The flange and the first gasket are clamped onto each other by the internal fixation arrangement between the first and second frame part. The oil sump assembly further comprises a second gasket arranged for sealing a connection between the first frame part and the engine mounting surface.

Accordingly, the oil reservoir can be mounted to the internal combustion engine by means of a floating suspension. In particular, the flange of the oil sump is mounted and sealed to the framework, so that the oil sump is floatingly suspended to the framework, rather than to the engine block. In other words, the design of the oil sump assembly allows a single person to pre-assemble the oil sump, gaskets and framework together to form a floating suspension, already before mounting the oil sump assembly as a unit to the engine block. As a result, the controllability and ease of the assembly process is improved while maintaining a floating oil sump design.

The internal fixation arrangement between the first and second frame part allows the framework to be assembled to the oil sump before the assembly is mounted to the engine block. The internal fixation arrangement can for example comprise a number of fixture screws for at least temporarily fixating the first and second frame part to each other. For example, the first frame part may be provided with threaded holes that are aligned with through holes in the second frame part, or vice versa. Alternatively, or additionally, other types of fixtures can be used to fixate the first and second frame part to each other, such as clamps, keys, press fits, or snap fits.

The interface provided by the framework allows mounting of a flange that is non-conformal to the engine mounting surface, e.g. having a different shape and size than the engine mounting surface.

Thus, the design of the oil sump assembly according to the present invention allows the use of a floating suspension oil sump ready for assembly handling, in production and at dealers, independent of the engine block interface. The design facilitates correct assembly of the gasket and oil sump, e.g. with a dedicated assembly rig and assembly tools, independent of the engine production line.

In preferred embodiments, to further facilitate the assembly process, the flange of the oil reservoir may be undersized with respect to the engine mounting surface, and the first frame part may radially extend beyond an outer contour of the flange for conforming to the engine mounting surface, and the second frame part may be removably fixated to a portion of the first frame part beyond the outer contour of the flange.

Preferably, the framework comprises an internal alignment arrangement for aligning the first and second frame part with respect to each other.

To facilitate mounting the oil sump assembly as a unit to the engine block, the framework may comprise an external alignment arrangement for aligning the first frame part and the engine mounting surface with respect to each other. Additionally, or alternatively, the framework may comprise an external fixation arrangement for fixating the first frame part to the engine mounting surface. For example, further through holes may be provided in the first and/or second frame part. The further through holes may be arranged such as to be aligned with threaded holes in the engine block, so that the oil sump assembly as a unit can be screwed to the internal combustion engine.

In order to prevent leakages between the framework and the flange of the oil sump, it is important that the first gasket seals the recess when clamped onto the flange by the first and second frame part. This can simply be achieved by having at least one sidewall of the recess formed by the first frame part. The remaining sidewalls of the recess can be formed by the second frame part.

For the same reason, preferably at least one sidewall of the recess provides a seating surface for positioning the first gasket in the recess. Accordingly, the first gasket can be correctly positioned and aligned with respect to the first and/or second frame part during the assembly process. For example, the at least one sidewall formed by the first frame part may comprise the seating surface, e.g. in the form of a groove. Alternatively, or additionally, a further seating surface may be provided by another sidewall of the recess that is e.g. formed by the second frame part. To facilitate the positioning of the first gasket with respect to the first and/or second frame part, the first gasket may comprise a sealing lip arranged for engaging with the seating surface. The sealing lip may be in the form of one or more protrusions, e.g. ribs or plugs, with a shape and size that correspond with a mating geometry of the seating surface. For example, the seating surface may comprise one or more grooves or holes for receiving the sealing lip.

Due to the floating suspension, the oil sump is able to move slightly with respect to the frame work, e.g. by elastic deformation of the first gasket. In order to prevent collision between the oil sump and the framework under such movements, in some embodiments the first gasket may comprise a skirt that extends between the second frame part and a sidewall of the oil reservoir.

To facilitate positioning and mounting of the second gasket during the assembly process, to ensure a proper seal between the framework and the engine block, a further seating surface may be provided. For example, when mounted to the engine mounting surface, a channel can be formed between the first frame part and the engine mounting surface, wherein the channel is arranged for aligning and securing the second gasket. The channel may at least partially be formed by the first frame part. For example, the first frame part may provide a U-shaped channel for receiving at least a part of the second gasket.

Other aspects of the present invention provide an internal combustion engine as defined in the appended claims, comprising the oil sump assembly described herein. By virtue of the oil sump assembly, the internal combustion engine can be provided with a floating oil sump, while the assembly process of the engine is relatively easy and controllable as compared to conventional arrangements.

Yet other aspects of the present invention provide a vehicle as defined in the appended claims, comprising the internal combustion engine described herein. The vehicle can e.g. be a truck or any other type of commercial or utility vehicle.

In other aspects, the present invention provides a method as defined in the appended claims, for assembling the oil sump assembly described herein, in an easy and controllable fashion. The method comprises: (i) mounting the first gasket to the flange such that the first gasket covers the first side and the second side of the flange; (ii) positioning the first frame part of the framework onto the first side of the flange, with the first gasket therebetween; (iii) positioning the second frame part onto the second side of the flange, with the first gasket therebetween, such that the flange is sandwiched between sidewalls of the recess by the first gasket covering the first and second side; and (iv) clamping the first gasket and the flange onto each other by fixating an internal fixation arrangement between the second frame part and the first frame part.

Optionally, the method further comprises the step of (v) connecting the oil sump assembly to an internal combustion engine by fixating the first frame part to the engine mounting surface with a second gasket therebetween.

The invention is described more fully hereinafter with reference to the accompanying drawings, in which embodiments of the invention are shown. In the drawings, the absolute and relative sizes of systems, components, layers, and regions may be exaggerated for clarity. Embodiments may be described with reference to schematic and/or cross-section illustrations of possibly idealized embodiments and intermediate structures of the invention. In the description and drawings, like numbers refer to like elements throughout. Relative terms as well as derivatives thereof should be construed to refer to the orientation as then described or as shown in the drawing under discussion. These relative terms are for convenience of description and do not require that the system be constructed or operated in a particular orientation unless stated otherwise.

illustrates an embodiment of an oil sump assemblyaccording to the present invention. The oil sump assemblycomprises an oil reservoirprovided with a flangethat circumferentially mounts the oil reservoirto an engine mounting surfaceof an internal combustion engine. The internal combustion engineincluding the oil sump assemblymay be part of a vehicle, such as a truck or any other kind of commercial or utility vehicle.

The flangemay be non-conformal to the engine mounting surface, in that they do not have the same shape and size. For example, the flangemay be undersized, e.g. smaller, with respect to the engine mounting surface. To interconnect the flangeand the engine mounting surface, the oil sump assemblycomprises a framework() which includes a first frame partand a second frame part. The flangeis floatingly suspended in the framework, which in turn can be mounted to the engine mounting surface.

The first frame partof the frameworkcircumferentially extends around the flangeon a first side thereof, e.g. an engine facing side of the flange, and provides an interface between the flangeand the engine mounting surface. The first frame partmay radially extend beyond an outer contour of the flangefor conforming to the engine mounting surface. The first frame part may be fixated to the engine block by means of a number of screws or other type of fastener

On a second side of the flangeopposite the first side, the second frame partis removably fixated to the first frame partby an internal fixation arrangement. For example, the second frame partmay be screwed to the first frame partby means of a number of fixture screws (not shown) or other fixation means. The second frame partmay be removably fixated to the portion of the first frame partthat is located beyond the outer contour of the flange

A recessis formed between the first and second frame part,. For example, as illustrated one sidewall of the recessis formed by the first frame part, while other sidewalls are formed by the second frame part. The flangeextends into the recessand is sandwiched between the sidewalls of the recessby a first gasketthat covers both the first and second side of the flange. For example, the first gasketmay have a U-shaped profile which can be slid over the flange in order to cover both its first and second side. Hence, the flangeand the first gasketare clamped onto each other in the recess, by the internal fixation between the first and second frame part,. Additionally, when the pre-assembled unit is externally mounted to the engine block, e.g. by means of screws, said screws may provide a further clamping force onto the flangeand first gasketin the recess.

The oil sump assemblyfurther comprises a second gasketarranged for sealing a connection between the first frame partand the engine mounting surface. For example as illustrated, a channelmay be formed between the first frame partand the engine mounting surfacewhen these are mounted to each other. The channel, e.g. having a U-shape, may thus be arranged for aligning and securing the second gasket. For example, a part of the second gasketmay extend into the channel.

provides a detailed view of the floating suspension of the flangeto the frameworkas obtained in the oil sump assembly of the present invention. As illustrated in the embodiment ofthe sidewall of the recessthat is formed by the first frame partmay provide a seating surfacefor positioning the first gasketin the recess. The first gasketoptionally comprises a sealing liparranged for engaging with said seating surface. The first gasketmay optionally further comprise a skirtthat extends between the second frame partand a sidewall of the oil reservoirin order to prevent direct contact between the oil reservoirand the framework.also shows how the second gasketmay at least partially extend into a channelin the first frame part. When the oil sump assembly is mounted to the engine, said channelmay be closed off by the engine mounting surface.

provides a bottom view of an embodiment of the oil sump assembly, showing the oil reservoirand the frameworkthat circumferentially extends around the oil reservoiralong its flange (not shown). The oil reservoirmay have any form, size and shape, and may be made of a suitable material including e.g. steel, aluminum, a polymer, or a composite. The frameworkprovides an interface between the flange and the engine mounting surface of the internal combustion engine, such that the oil sump assembly as a unit can be attached to the engine mounting surface while the flange is floatingly suspended to the framework.

As illustrated in, the frameworkcomprises an internal fixation arrangementfor fixating the first and second frame part to each other. The internal fixation arrangemente.g. comprises one or more fixture screws or any other type of fixture element. To ensure proper alignment between the first and second frame part of the framework, the frameworkmay further comprise an internal alignment arrangement, e.g. comprising one or more mating edges, ridges, protrusions, holes, or dowel pins. The internal alignment arrangementmay be formed by the one or more fixture screws or other type of auxiliary fasteners that fixate the first and second frame part to each other. The internal fixation and/or alignment arrangement,allows the oil sump and the framework to be pre-assembled as a unit.

To ensure that the framework, and thus the oil sump assemblyas a whole, can be properly aligned with and fixated to the engine mounting surface, the frameworkmay comprise an external fixation arrangementand an external alignment arrangement. The external fixation arrangement e.g. comprises a number of bolts or other type of fastener arranged around the outer contour of the flange for fixating at least the first frame part to the engine mounting surface. The external alignment arrangementcan e.g. comprise a number of mating alignment elements in the frameworkand/or the engine mounting surface. Alignment elements e.g. include holes, edges, protrusions, dowel pins, and the like.

and B provide a detailed view of the internal and external fixation arrangement,.provides a section view of, over section line A-A′. As shown, the first and second frame part,are screwed together by a fixture screw, which at least temporarily applies the clamping force on the flangeand first gasketin the recessand allows the oil sump and frameworkto be pre-assembled as a unit. Said unit of the frameworkand oil sump can subsequently be screwed to the engine block by further screws.

illustrates an embodiment of a methodfor assembling the oil sump assembly described herein. In a first step Sof the methodthe first gasket is mounted to the flange such that the first gasket covers the first side and the second side of the flange. Next in step Sthe first frame part of the framework is positioned onto the first side of the flange, with the first gasket in between. In step Sthe second frame part is subsequently positioned onto the second side of the flange, with the first gasket in between, such that the flange is sandwiched between sidewalls of the recess by the first gasket covering the first and second side. The first gasket can e.g. have a U-shaped profile that can be slid over the flange in such a way that it covers both the first and second side. The first gasket and the flange are then clamped onto each other in step S, by fixating the second frame part to the first frame part, e.g. by means of a number of screws or other type of internal fixation arrangement. The end result of the methodis pre-assembled oil sump assembly as described herein, which can be mounted as a unit to an engine block.

Optionally, the methodfurther comprises the step Sof connecting the oil sump assembly to an internal combustion engine by fixating the first frame part to the engine mounting surface with a second gasket therebetween.

It will be clear to the skilled person that the invention is not limited to any specific embodiment herein described and that combinations or modifications are possible, in as far as these can be considered within the scope of the appended claims. Also kinematic inversions are considered inherent to the invention disclosed herein. In the claims, any reference signs shall not be construed as limiting the claim.

The terms ‘comprising’ and ‘including’ when used in this description or the appended claims should not be construed in an exclusive or exhaustive sense but rather in an inclusive sense. Thus expression as ‘including’ or ‘comprising’ as used herein does not exclude the presence of other elements, additional structure or additional acts or steps in addition to those listed. Furthermore, the words ‘a’ and ‘an’ shall not be construed as limited to ‘only one’, but instead are used to mean ‘at least one’, and do not exclude a plurality. Features that are not specifically or explicitly described or claimed may additionally be included in the structure of the invention without departing from its scope.

Expressions such as: “means for . . . ” should be read as: “component configured for . . . ” or “member constructed to . . . ” and should be construed to include equivalents for the structures disclosed. The use of expressions like: “critical”, “preferred”, “especially preferred” etc. is not intended to limit the invention. To the extent that structure, material, or acts are considered to be essential they are inexpressively indicated as such. Additions, deletions, and modifications within the purview of the skilled person may generally be made without departing from the scope of the invention, as determined by the claims.