Fusion arrangement through modular, one-piece two-cylinder two-stroke crankshaft with split center bearing support as well as adapter and split flange housing for mounting two motorcycle cylinders on existing single-cylinder scooter housings

Abstract

(Main claim - crankshaft + center bearing) Crankshaft fusion arrangement (1) for a two-cylinder two-stroke reciprocating piston engine, characterized in that, that a one-piece crankshaft is made up of an inner part of a first shaft type and outer parts of a second shaft type, wherein shortened crankpins (2) connect the parts to each other in a form-fit and / or material-fit manner, the crankshaft is designed for a split center bearing support (3), and the arrangement can be inserted laterally into an unmodified original single-cylinder engine housing (7).

Description

Technical field:

[0001] The invention relates to the crankshaft assembly of two-stroke reciprocating internal combustion engines, in particular a modular, one-piece crankshaft fusion arrangement for combining components of different origins (e.g., motorcycle and scooter engine components) and a matching center bearing, flange and adapter plate system for mounting on existing original scooter housings without complex housing machining (simple "bolt-on" solution). State of the art:

[0002] Coupled crankshaft solutions are known, in which two partial shafts are joined using clamps or bolts. These solutions require complex coupling elements, have weak points against rotation, and necessitate extensive modifications to the original scooter casing, including complicated assembly procedures. However, none of the known systems combines a one-piece crankshaft with a split center bearing support, allowing installation in an unmodified original engine casing. Purpose of the invention:

[0003] The aim is to provide a highly durable, easy-to-assemble and modular overall solution that: 1. creates a one-piece crankshaft by fusing inner and outer parts of different shaft types; 2. offers a split center bearing support for easy installation in unmodified original scooter housings; 3. provides an adapter and flange housing system with an integrated “double-face design” that compensates for and seals different cylinder base sealing surface shapes; 4. Allows for different cylinder axis distances (especially 102 mm) and mounting angles; 5. is designed for different stroke values ​​(in particular 58 mm, alternatively 60 mm and 62 mm); 6. the use both on so-called “small block” (125-175 cm) 3 ) as well as “big block” scooter casings (over 200 cm³) 3 ) possible and permitted. Solution to the problem:

[0004] The invention comprises a one-piece fusion crankshaft (1) composed of an inner part of a first shaft type (motorcycle, quad) and outer parts of a second shaft type (classic motor scooter).

[0005] The connection is made via shortened crankpins (2), which are secured against rotation by a form-fit and / or material-fit connection, preferably by welding. Connecting rods (10) with a length of preferably 120-130 mm provide the necessary geometry.

[0006] A split center bearing support (3) enables the one-piece crankshaft to be installed laterally in the original engine housing (7), which is otherwise only possible with complicated and vulnerable split shaft concepts.

[0007] The adapter plate (5) is preferably a single piece, but can also be made in two parts. The integrated “double-face design” of the adapter plate compensates for different heights and shapes of the cylinder base sealing surfaces between scooter and motorcycle cylinders and simultaneously ensures a seal.

[0008] The cylinder center distance is preferably 102 mm, but can be varied. The assembly is suitable for air- or water-cooled cylinders (6). Advantages: • Increased stiffness and durability thanks to a one-piece crankshaft • Reliable anti-rotation through welding and / or form-fitting • Ease of assembly thanks to divisible center bearing support • Adaptable to different stroke values ​​(58 / 60 / 62 mm) • “Double-face design” compensates for and seals differences between the housing and cylinder base. • Easy integration into unchanged original scooter housings • Modular design for different cylinder, stroke and housing variants Brief description of the drawings: • Fig. 1: Exploded view of the overall assembly with fusion crankshaft (1), split center bearing support (3), split flange housing (4), one-piece adapter plate “Double-face” (5), • Fig. 2: Side view (perspective) of the assembled unit. Example of implementation (without limitation):

[0009] In a preferred embodiment, the fusion crankshaft (1) has a stroke of 58 mm. Alternatively, the stroke can be 60 mm or 62 mm, particularly when using eccentric crankpins.

[0010] The inner part is derived from a first shaft type with suitable center bearing guide, the outer parts from a second shaft type with dimensions suitable for the original motor housing (7).

[0011] The crankpins (2) are shortened, fitted together and secured at the contact points by welding.

[0012] The split center bearing support (3) is designed as a load-bearing element and is anchored both in the original engine housing (7) and in the flange housing (4).

[0013] The adapter plate (5) connects the flange housing (4) and the original engine housing (7) on both sides, can have a mounting angle relative to the crankcase reference surface and contains different sealing surface heights for both cylinder sides in a double-face design. Variations: • Variable stroke values ​​(58 / 60 / 62 mm) • Torsion resistance alternatively through positive locking or adhesive connections • Central bearing as rolling or sliding bearing • Adapter plate, one-piece or multi-piece, with or without media guides • Mirror-image versions and functionally equivalent variants included List of reference symbols (§ 5 GebrMV) 1 Fusion crankshaft made from scooter and motorcycle parts (one-piece) 2 shortened lifting pins, secured against rotation (e.g. welded joint or positive locking) 3 Center support (split) 4 flange housings (split) 5 Adapter plate 125-175ccm Small-Block (preferably one-piece, alternatively split) 6 Adapter plate 198ccm Big-Block (preferably one-piece, alternatively split) 7-cylinder engine (air- or water-cooled; OEM or aftermarket) 8 Original engine casings (only the front crankshaft area is shown in the drawing) 9 Fasteners / screws (optional) 10 sealing surfaces / seals (adapter plate to housing, housing to cylinder) 11 connecting rods (preferably 120-130 mm; in the exemplary embodiment 125 mm) 12 bearings (rolling or sliding bearings; center bearing shown in the drawing) 13 Mounting brackets / reference surface (adapter plate relative to flange / original housing)

Claims

[1] (Main claim - crankshaft + center bearing) Crankshaft fusion assembly (1) for a two-cylinder two-stroke reciprocating engine, characterized by , that a one-piece crankshaft is made up of an inner part of a first shaft type and outer parts of a second shaft type, wherein shortened crankpins (2) connect the parts to each other in a form-fit and / or material-fit manner, the crankshaft is designed for a split center bearing support (3), and the arrangement can be inserted laterally into an unmodified original single-cylinder engine housing (7). [2] (Sub-claim to claim 1) Arrangement according to claim 1, characterized by that the material-bonded fastening includes a welded connection at at least one joint. [3] (Subclaim to claim 1) Arrangement according to any of the preceding claims, characterized by, that alternatively or additionally, positive locking elements such as splined, wedge, polygon or profile teeth are used to prevent twisting. [4] (Subclaim to claim 1) Arrangement according to any of the preceding claims, characterized by , that the stroke of the crankshaft is 58 mm, alternatively 60 mm or 62 mm, particularly when using eccentric crankpins. [5] (Subclaim to claim 1) Arrangement according to any of the preceding claims, characterized by , that connecting rods (10) with a length of 120-130 mm are used. [6] (Subclaim to claim 1) Arrangement according to any of the preceding claims, characterized by , that the divisible central bearing support (3) acts as a load-bearing element, providing support both axially and radially and is held detachably in the original motor housing (7) as well as in the flange housing (4). [7] (Main claim - adapter plate) Adapter plate arrangement (5) for mounting a two-cylinder unit (6) on an original engine housing (7), characterized by , that the adapter plate is designed as a single piece or in two parts, and can be screwed to both a flange housing (4) and the original motor housing (7). and features an integrated double-face design, which compensates for and seals the different heights and shapes of the cylinder base sealing surfaces between scooter and motorcycle cylinders. [8] (Sub-claim to claim 7) Arrangement according to claim 7, characterized by that the cylinder center distance is preferably 102 mm, but other distances are possible. [9] (Sub-claim to claim 7) Arrangement according to one of claims 7 or 8, characterized by , that the adapter plate (5) has a defined mounting angle relative to the housing reference surface, to comply with space and peripheral requirements. [10] (Subclaim to claim 7) Arrangement according to any one of the preceding claims 7 to 9, characterized by , that media channels (13) for cooling and / or lubricating agents are integrated into the adapter plate. [11] (Subclaim to claim 7) Arrangement according to any one of the preceding claims 7 to 10, characterized by , that the adapter plate (5) for scooter housings up to 175 cm 3 (“Smallblock”) and over 200 cm 3 is designed for (“Bigblock”). [12] (Main claim - complete assembly) Modular motor assembly comprising: • a crankshaft fusion arrangement according to any one of claims 1-6, • a center bearing / flange housing arrangement according to one of claims 7-11, • and an adapter plate arrangement according to one of claims 7-11, characterized by, that the assembly enables the mounting of air- or water-cooled two-cylinder units (6) on an original engine casing (7). [13] (Sub-claim to claim 12) Motor assembly according to claim 12, characterized by , that the crankshaft (1) and the adapter plate (5) can be adapted to different cylinder axis distances and stroke values. [14] (Sub-claim to claim 12) Motor assembly according to one of claims 12 or 13, characterized by that all assembly modules are interchangeable and can be used separately as spare parts. [15] (Subclaim to claim 12) Motor assembly according to any one of claims 12 to 14, characterized by , that the adapter plate (5) and the flange housing (4) include mounting hole patterns suitable for both OEM and aftermarket cylinders. [16] (Sub-claim to claim 12) Motor assembly according to any one of claims 12 to 15, characterized by, that the assembly can be mounted without structural modifications to the original engine housing (7).

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