Abstract: According to one embodiment, a crank portion is formed from a crank piece, an element separate from a shaft portion. The crank piece includes a fitting hole in which the shaft portion is fit by predetermined “interference” and a slit-like slot with one end opened in an inner circumferential surface of the fitting hole, and an other end closed inside the crank piece. The fitting hole is deformed so as to expand its diameter when expanding a width of the slot. The shaft portion is fit in the fitting hole of the crank piece by the predetermined “interference” when inserted in the deformed fitting hole and the fitting hole restores an original form while the shaft portion is in the fitting hole.

Abstract: In accordance with certain embodiments, a modular crankshaft features a connection system between modules that features opposed female receptacles. A pin having opposed beveled ends and hydraulic passages with it is inserted into the opposed receptacles. A pair of seals is disposed on the beveled ends and straddles a hydraulic fluid outlet. The crankshaft wall that defines each receptacle is designed to flex in response to applied hydraulic pressure between the seals on the tapered pin portion. A notch at the base of the receptacle in the crankshaft reduces stress concentration and enables the wall defining the crankshaft receptacle to come back when hydraulic pressure through the pin is removed. The opposed crankshaft receptacles are flanged to allow them to be pulled together over the pin. An interference fit results around the pin after the flanges are mated and the hydraulic pressure is removed.

Abstract: A piston pin carries out an eccentric coupling of connecting rod and crank connected with the driving shaft. The piston pin is shaped like a cylinder, has two cuts disposed orthogonally to the axis of the piston pin. The cuts form three sectors. The two external sectors correspond to the connection with the crank and the internal sector is coupled to the connecting rod.

Abstract: An eccentric shaft for an internal combustion engine, especially for a rotary combustion engine, the working unit of which comprises essentially a peripheral housing, side housing plates, and a triangular piston mounted on an eccentric of an eccentric shaft, the tips of the piston moving along an epitrochoidal orbit inside the peripheral housing to form three separate working spaces, where the rotary combustion engine can have several working units. The eccentric shaft consists of several parts, which have radial teeth at their ends, by means of which these shaft parts can be connected positively to each other by the use of a tie rod. In rotary piston engines with more than one working unit, as many inner shaft parts of identical design as there are working units can be used in modular fashion to construct the eccentric shaft.

Abstract: A multi-piece crankshaft having a shaft with two ends and in which the shaft is adapted to rotate about its shaft axis and a crankpin with at least one indentation. The shaft and crankpin are placed within a mold having a first mold cavity corresponding in shape to the desired counterweight and the other end of the shaft is positioned within a second mold cavity corresponding in shape to a flywheel taper support for the crankshaft. The counterweight and flywheel taper support are then both formed by simultaneously casting a liquid material, such as zinc, into both the first and second mold cavities.

Abstract: A multi-piece crankshaft having a shaft with two ends, an axis and adapted to rotate about its axis. A crankpin also has two ends and an axis parallel to but spaced radially outwardly from the shaft axis. The crankpin optionally has at least one indentation. A plate has two spaced openings such that one end of the shaft is positioned in one of the plate openings while the other end of the shaft is positioned in the other plate opening. At least one counterweight extends between said one end of the shaft and said one end of the crankpin, and this counterweight is formed by casting a liquid metal around the ends of the shaft and the crankpin as well as around the plate. The liquid metal fills the at least one indentation and, upon hardening, locks the counterweight to the crankpin and shaft and encases the plate.

Abstract: A multi-piece crankshaft having a main shaft with two ends adapted to rotate about its axis. A crankpin also has two ends and an axis parallel to but radially spaced from the axis of the main shaft. At least one counterweight extends between one end of the shaft and one end of the crankpin and this counterweight is formed by casting a liquid metal around the ends of the main shaft and crankpin in a molding chamber. In a modification of the crankshaft, a hollow crankpin is disposed within the mold such that each end of the crankpin is positioned within a mold cavity corresponding to a counterweight. Upon casting the liquid metal in the mold cavities forming the counterweights, the molten metal flows inwardly from both ends of the crankpin and joins together to form a continuous metal connection between the counterweights.

Abstract: A method for making a multiple piece crankshaft from a shaft and a crankpin is disclosed. A notch is first machined on an intermediate section of the shaft such that the notch has a length slightly less than the length of the crankpin. Mating surfaces are then formed on the shaft at opposite ends of the notch. Thereafter, the crankpin is positioned on the mating surfaces on the shaft so that the crankpin is parallel to and spaced from an axis of the shaft. The ends of the crankpin are then secured to the mating surfaces formed on the crankshaft and a portion of the intermediate section of the shaft is then removed by machining. A counterweight is finally positioned over each end of the crankpin at its juncture with the main shaft and secured to the crankpin and shaft thereby forming the crankshaft. Alternatively, the crankpin is positioned on mating surfaces formed on the counterweights and fasteners then secure the crankpin, counterweights and main shaft together.

Abstract: A multi-piece crankshaft having a main shaft with two ends adapted to rotate about its axis. A crankpin also has two ends and an axis parallel to but radially spaced from the axis of the main shaft. At least one counterweight extends between one end of the shaft and one end of the crankpin and this counterweight is formed by casting a liquid metal around the ends of the main shaft and crankpin in a molding chamber.

Abstract: A motorcycle flywheel assembly which includes a fork rod and a blade rod are positioned on a common crank pin. The crank pin has threaded nut bearing end portions, non-tapered cylindrical portions adjacent the nut bearing end portion, and a central bearing surface portion. A shoulder is defined where the cylindrical portion steps down from the central bearing surface portion. The cylindrical portions of the crank pin are positioned in crank pin receiving openings of flywheels in interference fit relation with the shoulder defined where the cylindrical portion steps down from the central bearing surface portion engaging first face of each flywheel, thereby precluding flexing movement of the crank pin.

Abstract: An improved crank apparatus for an internal combustion engine having a crankshaft, an arm extending outwardly of the crankshaft, a crank pin affixed to the arm, a sleeve member having an elongated slot formed therein so as to receive the crank pin therein, and a piston rod with a circular bearing area receiving the sleeve member therein. The crank pin has a generally rectangular configuration with first and second tabs extending outwardly from opposite sides of the crank pin. The first tab has an outer surface with a length greater than a thickness of the crank pin. The crank pin is slidable in the elongated slot during the rotation of the crankshaft. The circular bearing area has an insert key positioned therein. the insert key bears on a surface of the sleeve member during the rotation of the crankshaft. The insert key contacts the outer surface of the first tab during at least a portion of the rotation of the crankshaft so as to cause the crank pin to slide longitudinally through the elongated slot.

Abstract: A split flywheel and crank pin apparatus having a pair of flywheels held in a preselected spaced relationship to rotate about a common axis by a pin spaced from the axis. The pin has a central section and opposed ends. Each end has an undulating surface with a continuously varying radius for a circumferential path along the surface and a constant radius along a path on the surface parallel to a main axis of the pin. The pin ends are snugly received in bores in respective flywheels that have internal surfaces that mirror the pin end surfaces. The pin ends are separated from the pin central section by shoulders that abut facing surfaces of the flywheels. The pin is held in each flywheel by a nut. The pin includes lubricating passageways for lubricating a journal surface of the pin central section.

Abstract: A compressor running gear and method for assembling the running gear. The running gear includes a split housing having a first housing portion having a first wall and a second wall. Each wall includes at least one shoulder and a shroud. The split housing also includes a second housing portion adapted to be mated with the first housing portion, the first and second housing portions together define a housing chamber. The running gear also includes a crank assembly located in the housing chamber. The crank assembly includes first and second bearing carriers which are mounted on a crankshaft. Each of the bearing carriers has at least one arm adapted to be seated on the at least one shoulder.

Abstract: An improved crank apparatus for a crankshaft of a diesel engine including an arm extending outwardly of the crankshaft, a crank pin affixed to the arm and having a generally rectangular configuration, a split sleeve having a slot formed therein so as to receive the crank pin therein, and a piston rod affixed to the split sleeve and having an insert key affixed thereto so as to reside within the split sleeve in contact with the crank pin during a rotation of the crankshaft. The crank pin includes a first tab extending outwardly therefrom and a second tab extending outwardly from an opposite side of the crank pin. The first and second tabs extend through an opening formed in the split sleeve from the slot. These tabs include chamfered edges extending away from the generally rectangular configuration. The insert key is positioned so as to reside within an interior area of the split sleeve as the crankshaft rotates.

Abstract: A crankshaft of a V-type 6-cylinder internal combustion engine including first to sixth crank pins connected with connecting rods, having first to fourth crank journals between the first to sixth crank pins, and first to ninth crank arms between first to sixth crank pins and the first to fourth crank journals, the combination including a first balance weight provided to the first crank arm, a center of gravity of the first balance weight being mal-distributed to a lower part with respect to a center axis of the crankshaft, a second balance weight provided to the second crank arm, a center of gravity of the second balance weight being mal-distributed to a lower part, and deviated from the first balance weight in a counterclockwise direction, third and fourth balance weights provided respectively to the fourth crank arm and sixth crank arm, the centers of gravity of the third and fourth balance weights being mal-distributed to be orthogonal to the center of gravity of the first balance weight in a clockwise dir

Abstract: A driving arrangement for driving a snowmobile having an improved power transmission system that is comprised of a split engine having two cylinder blocks each containing at least a pair of cylinders with their output shafts connected to each other. A belt drive shaft is journaled by the engine assembly and is driven off the output shafts at the point where they are joined together. The belt drive shaft drives the drive belt of the snowmobile through a variable pulley transmission. Several embodiments of driving connections between the output shafts and the belt drive shaft that accommodate angular motion while transmitting large driving forces are disclosed. These include both splined connections and/or connections including flexible couplings.

Abstract: This invention is directed to an improved eccentric crank assembly for a reciprocating piston type air compressor. The eccentric crank assembly includes an eccentric plate, a compressor shaft, and an eccentric shaft. The eccentric plate is provided with a pair of parallel overlapping openings formed therethrough. The compressor shaft includes one end provided with a flat angled surface, and the eccentric shaft includes one end provided with a corresponding flat angled surface. The angled surface ends of the shafts are disposed within the openings of the plate. When the eccentric shaft is moved away from the compressor shaft, the angled flat surfaces force the shafts radially apart and into engagement with the openings of the eccentric plate, thereby locking the shafts and the eccentric plate together.

Abstract: An internal combustion engine has a crankcase, an output crankshaft, and an input shaft assembly. The input shaft assembly has an input shaft and a crank plate press-fit connected to the input shaft. The crank plate comprises a single sheet metal member with slightly elongate radial slots adapted to receive the crankpin of the output crankshaft. The slots are open ended to allow for misalignment between the output crankshaft and the input shaft whereby the crankpin can longitudinally move in its crank plate slot.

Abstract: A crankshaft having a high stress portion including a crankpin and an eccentric. The high stress portion is formed of a forged steel material having a first axial end. A reduced stress portion is formed from an unforged steel material and generally comprises a tubular cylindrical portion having a second axial end. The first axial end is secured to the second axial end by friction welding. A separate counterweight is attached to either the high stress portion or the reduced stress portion.

Abstract: The design and construction of past piston assemblies having a wrist pin retained by a pair of snap rings positioned in a groove. Other past piston assemblies have a stubpin or cap positioned within a bore of a piston member or the wrist pin. In these applications the stubpin or cap is in continuous contact along the interface between the bore and the stubpin or cap. The present invention provides a device for retaining a wrist pin within a pair of bores of a piston member during operation of an engine. The device includes a shank portion having an outer portion thereon and only the outer portion of the shank portion being in contact with an inner surface of the wrist pin. The device and the wrist pin forming a wrist pin assembly. Thus, the device remains positioned within the inner surface and properly positioned the wrist pin assembly within the bores during operation of an engine within a bore of a cylinder liner.

Abstract: A snowmobile having an improved power transmission system that is comprised of a split engine having two cylinder blocks each containing at least a pair of cylinders with their output shafts connected to each other. A belt drive shaft is journaled by the engine assembly and is driven off the output shafts at the point where they are joined together. The belt drive shaft drives the drive belt of the snowmobile through a variable pulley transmission.

Abstract: A crankshaft having a high stress portion including a crankpin and an eccentric. The high stress portion is formed of a forged steel material having a first axial end. A reduced stress portion is formed from an unforged steel material and generally comprises a tubular cylindrical portion having a second axial end. The first axial end is secured to the second axial end by friction welding. A separate counterweight is attached to either the high stress portion or the reduced stress portion.

Abstract: An assembled shaft in the case of which sleeves are inserted into tubular members for the purpose of connecting tubular portions inserted into each other or abutting each other and/or for attaching elements slid on to the tubular members, which sleeves are radially deformable beyond their limit of elasticity by internal pressure application. This assembled shaft includes sleeves each having a cylindrical portion for resting against the tubular member as well as end faces with round apertures for sealing on a reduced diameter.

Abstract: A crankshaft including an eccentric cranked section which is divided into two parts. A unitary inner ring is force fit over the outer surfaces of both parts of the cranked section of the crankshaft. At each axial end of the inner ring, a groove is opposite a hole in the shaft. A connecting pin extends between them. This prevents rotation of the inner ring around the cranked section of the shaft. For strengthening the cranked section, there is a continuous bore hole through both of its parts and a connecting screw extending through the bore hole. A support for the connecting rod engages the crankshaft cranked section at the bearing inner ring.

Abstract: The invention is directed to a composite crankshaft for a two-stroke engine for portable handheld work tools including chain saws, cutoff machines and the like. In composite crankshafts, a crank pin is connected to a crank web by a press fit wherein the inner diameter of the press-fit bore is expanded toward its axial end in order to reduce stress peaks. In this way, the press-fit surface has a radial spacing with respect to the center longitudinal axis of the press fit which changes. The press fit of the crankshaft of the invention is so configured that the radial distance of the press-fit surface changes in dependence upon the axial spacing to the axial center of the press fit according to an exponential function having the equation f(x)=a.multidot.e.sup.b.multidot.x wherein (a) and (b) are pregiven constants, (x) is the axial spacing and f(x) is the radial spacing.

Abstract: An assembled crankshaft whose crank webs on both sides are connected to, so as to be integral with, part of an adjoining shaft pin, with these parts being designed as hollow pins, and in the case of which crankshaft the parts of adjoining crank webs jointly forming a shaft pin are at least partially stepped in their diameter and inserted into each other, with the outer part having a higher yield point than the inner part and with a force-locking connection existing between the two parts.

Abstract: A camshaft comprising a steel shaft and a plurality of cam pieces fitted on the shaft. The cam piece is made from a sintering alloy material and bonded to the shaft by sintering. The shaft has pin-receiving holes perpendicular to the axis of the shaft. The cam piece is formed on its side surface with a pin-receiving groove. A positioning pin has a lower portion tightly fitted in the hole of the shaft and an upper portion fitted in the groove to position the cam piece with respect to the shaft during sintering.

Abstract: A two cycle engine having multiple cylinders which is capable of expanding from two or four or more cylinders. A composite crankshaft is built up by combining components including crank webs, bearing shafts and crank pins. A composite crankcase also may expand to accommodate the number of cylinders required through the use of common mating surfaces. The mating surfaces provide opposed thrust surfaces for each pair of crank pins.

Abstract: In the formation of a crankshaft, such as used in small gasoline motors for lawn motors, chain saws and the like, separately produced crank webs, shaft pins and crank pins are used to form an integral crankshaft. Initially the various parts are shaped to the desired dimensions. The crank web can be stamped from a metal strip or it can be a forged sintered part. A shaft pin is inserted in sliding contact with an opening in a crank web and then the two parts are secured together by pressure welding. Another crank web and shaft pin are assembled in a similar manner. The two webs are then interconnected by a crankpin positioned in another opening in each of the webs and a connecting rod is installed on the crankpin.

Abstract: A crankshaft assembly including a pair of crankshafts and an intermediate crank arm, wherein a through opening is formed in a crank web of each of the crankshafts to extend axially of the respective crankshaft. In assembling the part, one crankpin of the intermediate crank arm is force fitted in an opening formed in a crank arm of the one crankshaft and a jig having a columnar portion is inserted in the through opening formed in the one crankshaft to support the one crankpin, thereby providing a crankshaft sub-assembly. When another crankpin of the intermediate crank arm is force fitted in an opening formed in a crank arm of the other crankshaft, the pressure applied to the crankpin is borne by the jig, so that the other crankshaft can be accurately secured to the intermediate crank arm.

Abstract: A reciprocating piston machine, such as an internal combustion engine, includes a modular power transmission subassembly including a built-up crankshaft, integral unsplit crankshaft journal supports and bolt-less connecting rods to provide a lightweight low cost engine construction. A built-up crankshaft with improved oil lubrication means is also disclosed.

Abstract: A connecting-rod system particularly for mowers, wherein a crank, supporting a couple of rods, is linked to the driving shaft by means of a clamp fastened to said shaft by means of a threaded ring, and wherein the mutual positioning of crank and clamp is achieved by means of a key.

Abstract: The crankshaft is of the type comprising, in succession in its longitudinal direction, a crank pin intended to receive a connecting rod big end, an eccentric of flattened sector shape, and an elongate tubular part, non-coaxial with respect to the crank pin and acting partly as a journal and partly as a support for a rotary member, such as a rotor of an electric motor. The crank pin and the eccentric are made in a single metal piece and the elongate tubular part is constituted by a separate tubular metal piece. The face of the eccentric which is turned towards the tubular piece and the corresponding end of this piece have respective annular formations engaged and retained one in the other by means of welding or glueing.

Abstract: A crankshaft assembly for precision low load applications has cylindrical crankpins mounted on concave peripheral grooves on the ends of a crankshaft and coupled thereto by clamps which lockingly engage aligned annular grooves in the crankshaft and crankpin.