Abstract: An engine crankshaft has a crankpin that is radially slidably mounted relative to the crankshaft axis so that its axis can follow other than a circular path centered on the cranking axis. The mechanism includes at least one main bearing section with a stationary eccentric bearing surface, and at least one web fixed to the crankshaft and extending radially from the main bearing section. A housing is slidably mounted on guide surfaces on the webs for a sliding movement along the web, and has a crankpin secured thereto. The non-rotating eccentric bearing surfaces engaged by the housing force the housing to slide radially in and out along the web in synchronism with rotation of the crankshaft such that the distance of the center of the crankpin axis from the center of the main bearing section axis varies as a function of the angle of rotation of the crankshaft.

Abstract: In a cutting machine having a reciprocating blade driven by a crank mechanism which includes an angularly balanced crank, the blade, the connecting rod which drives the blade and the connecting member which connects the blade to the connecting rod are dynamically counterblanced by a passive load, pair of connecting rods which drive the passive load in a direction opposite the direction of blade movement, and a pivoted link which cooperates with the pair of connecting rods to maintain the passiive load for movement in a predetermined path.

Abstract: A V-twin, two stage compressor has valve plates disposed between the head and cylinder of each stage and mounting free-floating flexible reed intake and exhaust valves therein. The flexible reeds are movably captured between the floors of respective reed recesses, and separate, non-fixed keeper bars are disposed over, but slightly spaced from, the reeds. Keeper bars over the exhaust reed extend above the valve plate for engagement by the head. A restrictor plate lies within a valve plate recess on keeper bars over the intake valve. A cored crankshaft providing motor drive shaft lubrication, and a removable counter-weight providing crankshaft use with one-piece connecting rods is disclosed. A cooling fan is driven by the removable counterweight and V-shaped fan shroud projections direct cooling air over the cylinders and heads while another cooling air port directs air over an intercooler.

Abstract: A stroke control has an eccentric member fitting on an eccentric member mounting portion of a drive shaft and the eccentric member is at an eccentricity with respect to the drive shaft and has sliding surfaces which are in sliding engagement with the eccentric mounting portion. A connecting rod rotatably carried by the outer peripheral surface of the eccentric member and swingably connected to the slide. A gear shaft extends through the eccentric member mounting portion and has spline-type gear teeth on end portions thereof, the gear shaft being rotatably supported by the eccentric member. A plurality of screw rods are arranged in parallel with the gear shaft such as to extend through the eccentric member mounting portion, the screw rods being fixed to the eccentric member. Gears screwed to the screw rods and meshing with the spline type gear teeth on the gear shaft, the gears contacting the eccentric member mounting portion.

Abstract: A low vibration crankshaft has crankarms of decreasing inertia/mass and stiffness as their distance torsional vibration node of the rotating vibration system increases. The mass and stiffness of the crankarms may be varied by changing the lateral width of the arms or by other means. The arrangement provides, in combination with an engine or other reciprocating piston machine, an increased or maximized torsional vibration resonant frequency and resulting lower or minimized angular deflections of the crankshaft in the condition of system resonance.

Abstract: A press with a stroke control device has a drive shaft having an eccentric member mounting portion with an eccentric member thereon, the eccentric member is at an eccentricity with respect to the drive shaft and has sliding surfaces which are in sliding engagement with the eccentric mounting portion, a cross slide supporting the eccentric member, and a slide which surrounds and supports the cross slide therein, the slide being slidable while supporting the cross slide which moves laterally when the eccentric member rotates with the drive shaft.

Abstract: The invention relates to a crankshaft drive for an internal-combustion engine of V-type with a crankshaft, which has two mutually offset crank pins per throw, which pins are interconnected via an intermediate web. In order both to minimize the amount of machining required on the intermediate web and to ensure an optimum axial guidance of two connecting rods mounted on the crank pins, the intermediate web has an axial stop collar on either side and the intermediate web is of an enlarged design such that the axial stop surface of the connecting rods cannot jut out from the projected area of the intermediate web in any crankshaft position.

Abstract: A crankshaft is provided which comprises a crankshaft body which is formed by forging. The crankshaft body includes a plurality of adjacent web core portions, crank pins interconnecting adjacent web core portions and journals which extend from the outermost of the adjacent web core portions. A plurality of balancer weights are formed by casting. Each of the balancer weights are integrally fored with, and surround, a corresponding one of the web core portions. Further, a method for manufacturing the crankshaft is disclosed.

Abstract: A crankshaft with bearing pins and crank pins whereby the crank pins are delimited by counter weights constructed as webs or arms that extend transversely to the longitudinal axis of the crankshaft. These counter weights are circumcirculated during the rotation of the crankshaft at least by an air-oil-mixture in a crankcase and in an oil pan of the internal combustion engine. For reducing the power losses of the internal combustion engine by oil and or air-oil-mixture displacements by the webs or arms, the latter are constructed in their area disposed remote from the crank pins in the manner of aerodynamic bodies.

Abstract: A handheld portable tool has a drive unit connected to the handle via damping elements. The drive unit includes an internal combustion engine having a crankshaft. To reduce the vibration transmitted by the drive unit to the handles, a static or dynamic imbalance of defined position and quantity is provided on the crankshaft of the engine, as a result of which vibration in the handles is considerably reduced. An imbalancing weight may for instance be provided in the fan wheel, so that the crankshaft and its elements are manufactured and balanced in the same manner as before, and only the fan wheel has to be structurally modified.

Abstract: A crankshaft for a 90.degree. V-type eight-cylinder internal combustion engine having eight balance weights of No. 1 through No. 8 balance weights and supported by five supports. An angle defined between the No. 1 and No. 2 balance weights is set at the range of 15.degree.-45.degree. and an angle defined between the No. 1 and No. 3 balance weights is set at the range of 45.degree.-75.degree.. The mass of each of No. 1 and No. 8 balance weights is greater than the weight of any one of No. 2 through No. 7 balance weights. These relationships can reduce the weight of a crankshaft and bearing loads.

Abstract: A balancer mass is reciprocated linearly in the plane of the piston/cylinders of a four cylinder in-line engine by a pair of cams mounted on the crankshaft for rotation therewith. The second order vibrations can be substantially eliminated either by mounting a single balancer of the invention at the center of the crankshaft or by using a pair of balancers mounted one each at opposite ends of the crankshaft. The vibrations can also be substantially reduced by mounting a single balancer at the "free end" of the crankshaft opposite the clutch and flywheel.

Abstract: A balancer shaft for use in a multicylinder engine comprises a balance weight part formed to be eccentric in relation to a rotation axis of the balancer shaft and disposed along the alignment of cylinders in a cylinder block, an elongated shaft part extending from the balance weight part along the alignment of cylinders, a driving device provided on an end portion of the elongated shaft part for transmitting the rotation of a crank shaft in the cylinder block to the balancer shaft, a first journal provided on the end portion of said elongated shaft part, a second journal provided on a central portion of the balance weight part, and a third journal provided on an end portion of the balance weight part. The first, second and third journals are supported respectively by first, second and third bearing portions provided in the cylinder block.

Abstract: A balance system for an internal combustion engine or the like includes a counterbalance weight pivotally mounted to the crankcase and driven in a reciprocating manner by a link assembly connecting the weight to an eccentric on the crankshaft. The pivoting weight not only counterbalances the piston acceleration and deceleration forces but also cancels the torsional forces created by the weight as it pivotally moves through an arc in response to piston movement. This is accomplished by locating the center of gravity of the balance weight between the piston bore centerline and the stationary pivot of the balance weight itself. This location for the center of gravity causes a torque to be generated by a force couple created by the piston inertial force vector, the balance weight interial force vector, and the distance between them. This torque counteracts the torque generated by angular acceleration of the balance weight itself, to thereby substantially eliminate all torsional vibrations.

Abstract: A balancing mechanism having a vertical robot arm and horizontal robot arm pivotally mounted to the vertical arm and for each robot arm a link mechanism having a lever as well as a spring connected to the robot arm to be balanced through the link mechanism so that the spring expands and contracts in accordance with changes in the quantity of movement which occurs as the robot arm rotates or travels so as to balance the robot arm.

Abstract: A balancer of a reciprocating machine having crank mechanisms includes an adjusting weight having one end supported by a reciprocating portion of a crank mechanism for the balancer. An adjusting weight support rotatably supports the other end of the adjusting weight with respect to a stationary portion of a body frame. The adjusting weight support is equipped with a weight support position altering mechanism for permitting alteration of the support position of the adjusting weight.

Abstract: The rotor of a driving device comprises an output shaft with transmission wheels fixed on the output shaft. The rotor is provided with a plurality of rotor bodies and a transmission device which is interlocked with the transmission wheels. Each rotor body is equipped with a plurality of rotating body parts on a support shaft in a free rotatable manner. Balance bodies are attached to these rotating body parts through pins located at eccentric positions of these balance bodies in a manner to provide free rotation. Crank bodies, driven by the rotating bodies, are freely-rotatably equipped on the support shafts. Where the output shaft rotates by an input from an external source, the rotating bodies also rotate at the same time. In addition, the balance bodies also rotate in association with the rotation of these rotating bodies. Therefore, the crank bodies prevent a state that parts of the balance bodies protrude outwardly from the rotating bodies. Thus, the inertial force of the rotating bodies is ensured.

Abstract: A crankshaft of a ferro-metallic material for reciprocating engines, particularly for internal combustion engines, includes bearing pins and crank pins whereby the crank pins are delimited by webs extending transversely to a longitudinal center axis of the crankshaft which are constructed as counterweights. For optimizing the crankshaft as regards weight and structural length combined with good mass balancing, the crank pins are provided with hollow bores in the direction of their center axis and the counterweights with heavy-metal bodies.

Abstract: A crankshaft and counterweights are balanced by adding additional weight without modifying their outer dimensions. Bores are drilled into the counterweights and then a slug of material which is of a different density than the original counterweight material is inserted into the drilled bore. The slug may be held in place by any suitable mechanism, e.g., press-fitting, upset fitting, welding or threading. Particularly with threading, a slug shorter than the bore may be positioned anywhere within the bore.

Abstract: Method and apparatus for counterbalancing an internal combustion engine while maintaining a lubricant flow path for supplying lubricant to a crankshaft connecting rod journal is disclosed wherein a generally cylindrical mass of crankshaft material is removed from a region of the crankshaft located coaxial with the connecting rod journal for engine balancing purposes with that removed mass including a portion of the lubricant passageway which supplies lubricant to the connecting rod journal. The region is then bridged by a tubular lubricant conduit to re-establish the lubricant path to the journal. Preferably the lubricant conduit is tubular and press fit into the existing passageway portions on opposite sides of the region with the lubricant passageway typically being a hole of uniform circular cross section extending oblique to the crankshaft axis of rotation and with the hole inside diameter substantially matching the outside diameter of the tube.

Abstract: In a punching machine, a yoke is supported on an eccentric section of the crankshaft. The yoke is designed to counterbalance the rotating forces. Both ends of the yoke are pivotably connected to connecting rods. Both connecting rods are pivotably connected, in turn, to a vertically-guided counterbalancing weight to counterbalance the oscillating forces.

Abstract: A first eccenter sleeve allocated to the drive of the devices operative for the balancing of masses is drivingly connected to the eccenter shaft by means of a displaceable locking bolt. The first eccenter sleeve is provided with pins and slide rings engaging into slots in the second eccenter sleeves. The second eccenter sleeves are connected via punch connecting rods to the ram of the machine. Slides are supported in the machine frame, which slides can be moved into slots provided in the second eccenter sleeves. Accordingly, all three eccenter sleeves can be held against rotation on the eccenter shaft. The drive connection between eccenter shaft and all eccenter sleeves proceeds accordingly via one single connecting member, namely the locking bolt. And this locking bolt operates together with one eccenter sleeve. Accordingly, no splined shafts which must be machined extremely precisely but are prone to knock out during operation are necessary.

Abstract: A crankshaft for a V-6 type of internal combustion engine having longitudinally spaced journals and crank pins connected by a series of nine arms numbered from the front end to the rear end of the crankshaft is provided with counterweights on the first, second fifth, eighth, and ninth arms only. A line between a longitudinal axis of the crankshaft and an axis of a forwardmost crank pin defines, with the longitudinal axis, a reference plane. The centers of gravity of the first and ninth counterweights lie in the reference plane on opposite sides of the longitudinal axis and balance each other. The centers of gravity of the second and eighth counterweights are disposed counterclockwise and clockwise in the same quadrants, respectively, from positions that are 150 degrees and 30 degrees clockwise from the reference plane, when the crankshaft is viewed from the front.

Abstract: An engine block is provided including multiple cylinders having pistons reciprocal therein connected to separate crankshaft sections journalled from the block by connecting rods. The block also journals a countershaft to whose opposite ends the crankshaft sections are drivingly connected through the utilization of power transmitting assemblies each including a clutch assembly and releasable drive connection structure incorporating and indexing mechanism for indexing the corresponding shaft section to the countershaft in the same indexed position each time the corresponding clutch assembly is actuated. The clutch assembly of each power transmitting assembly is interposed, in the path of transmission of power from the corresponding crankshaft section to said countershaft, intermediate the crankshaft section and the corresponding drive connection structure.

Abstract: A rotary crankshaft has multiple cranks. Each crank drives a reciprocating member in a cylinder or guideway via a con rod. Main counterweights are attached to the crankshaft and rotate therewith. Two contraweights rotate in the opposite direction from the crankshaft and at the same RPM as the crankshaft. The two contraweights are generally rotatably mounted on the crankshaft, coaxial therewith, and near each end of the crankshaft. The two contraweights are driven from the crankshaft by toothed gearing. The two contraweights plus the main counterweights combine forces so as to counterbalance the primary reciprocating inertia forces of a plurality of said reciprocating members.By proper adjustment of the size and angular location of both the main counterweights and the two contraweights, it is possible to obtain near perfect primary balance under any or all of the following conditions:(a) Any number of cranks.(b) Non equal reciprocating weights.(c) Non equal crank throws.

Abstract: An internal combustion engine having a pair of balancing shafts carrying eccentric balancing weights and driven in a direction of counterbalancing effects of reciprocating parts. Each balancing shaft is positioned to extend in parallel with the crankshaft and supported by bearings of which upper portions are defined by deck portions formed in the cylinder block. Compact arrangements can be accomplished by the locations of the balancing shafts.

Abstract: A balancing mechanism for reducing the vibration of a piston type internal combustion engine having a crankshaft and a camshaft comprises one or more reciprocating balance weights driven by two rotating cams with at least one of said cams being driven by either said crankshaft or said camshaft.

Abstract: An engine is disclosed in which two cylinders or guideways are mounted in a Vee or L formation with a reciprocable piston or crosshead in each. Connecting rods interconnect each reciprocable member to a crankshaft. Countershafts with balance weights thereon are referred to as balance shafts and these are driven at twice cranshaft speed in opposite directions and they serve to counterbalance the secondary reciprocating inertia forces. The balance shafts are mounted substantially parallel to the crankshaft instead of at right angles to the crankshaft as taught by Lanchester in a Vee machine. Thus, ordinary gearing can be used to drive the balance shafts instead of the skew gearing taught by Lanchester in a Vee machine. When the angle between the two cylinders is 90 degrees, only two not four balance shafts are required. When the machine has four cylinders in a 90 degree Vee, only two parallel balance shafts are required to serve all four cylinders. For some applications, three balance shafts are used.

Abstract: A balancing device for a press slide arranged in a vacant space of the press frame has an eccentric ring portion 180.degree. out of phase with an eccentric portion of the crank shaft attached to an end of the crank shaft and, a balancing weight slidable on guide posts and reciprocated vertically through a slide-block mounted in the eccentric ring.

Abstract: A balancer structure for a three-cylinder engine for eliminating the vibration in the engine especially the vibration caused by an inertia couple about an axis perpendicular to the crankshaft of the engine. A countershaft is rotated at the same speed as the crankshaft but in opposite direction. Two counterweights are secured to the crankshaft corresponding to the first and third cylinders of both ends for balancing of reciprocating masses and rotating masses. A counterweight is secured to the crankshaft for balancing of rotating masses. At least two balancers are secured to the countershaft at both ends thereof.

Abstract: This four stroke V-configuration engine has two cylinder banks which have equal numbers of cylinders, angled with respect to one another at a bank angle .alpha. different from 90.degree.. For each bank of cylinders, the angular positions of the crank shaft crank pins therefor are evenly spaced apart around the central axis of the crank shaft, and between the banks of cylinders the angular positions of a pair of corresponding cylinders are separated by a crank angle of 90.degree.-.alpha.. A first set of balance weights is provided so as to rotate about an axis parallel to the rotational axis of the crank shaft in the same direction and at the same speed as the crank shaft, and a second set of balance weights is provided so as to rotate about an axis parallel to the rotational axis of the crank shaft in the opposite direction and at the same speed as the crank shaft.

Abstract: The present invention provided a balancing arrangement for an eight cylinder horizontally opposed internal combustion engine construction having a housing and a four throw crank shaft rotatably mounted within the housing. A pinion is coaxially attached to each axial end of the housing and includes a counterweight radially spaced from the axis of rotation of the crank shaft. At least one idler pinion is rotatably mounted to the housing and in mesh with each crank shaft pinion and each idler pinion includes a weighted portion radially spaced from its axis of rotation. Both the counter weights and the weighted portions of the idler pinions are angularly spaced from each other by a predetermined amount so that, during rotation of the crank shaft, the centrifugal force vectors of the crank shaft counterweight and idler pinion weighted portions cancel the primary moment generated by the piston reciprocation acting on axially spaced positions along the crank shaft.

Abstract: An eccentric press which can be constructed a single connecting rod machine or a twin connecting rod machine is described. The press includes a stroke adjustment means having a support lever which is articulately connected at the joint between the two portions of a lever arrangement. The articulation joint is guided on an adjustable path of movement and the foot point of the support lever is guided variably in its position on a circular arc, the center point of the circular arc coinciding with the position of the articulation point which corresponds to the bottom dead center of the ram. As a result, a change in the ram stroke does not change the bottom dead center of the ram, only one ram stroke being executed per connecting rod revolution.

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 balancing device for a V-type internal combustion engine in which the angle of the V is not equal to 90.degree.. The balancing device comprises a shaft that is rotatable about an axis parallel to the axis of the crankshaft and which is driven at the same speed as the crankshaft but in the opposite direction. A first balancing mass is affixed to this shaft for balancing the first order inertial forces of the reciprocating masses of the cylinders and a pair of masses disposed on opposite sides of the first mass for balancing the couples generated by the offset of the connecting rods of the cylinders.

Abstract: A reciprocating type gas compressor comprises a hollow frame or housing having spaced apart end walls, a motor-driven crankshaft disposed within the housing and rotatably mounted on bearing assemblies on the end walls and connecting rods connected to crank pins on the crankshaft for driving pistons located within the housing. The crankshaft comprises a drive shaft at one end and a pump shaft the other end, both extending along a common axis of rotation. The crankshaft also comprises a pair of axially spaced apart counterweights located between the two shafts and a crank arm or link located between the counterweights. A crank pin extends from each counterweight to the link along a pin axis which is parallel to and spaced apart from the common axis of rotation. Each bearing assembly has a hollow cylindrical inner race which is friction-fitted on a shaft at an end of the crankshaft and abutts the side of one counterweight.

Abstract: A mechanical mechanism, for use in an internal combustion engine for changing rectilinear movement of a piston to rotational movement of a crankshaft, is of simple construction and has a minimum number of parts. A small gear with teeth formed on its external peripheral portion is stationarily mounted to a wall of an engine, and receives a first portion of a crankshaft, the crankshaft being rotatable with respect to the gear and the wall about an axis. A second portion of the crankshaft opposite the first is also mounted for rotation with respect to a stationary member. A third portion of the crankshaft is offset from the axis. A balancing structure comprising first and second balance bodies interconnected by a collar, and is mounted so that the crankshaft third portion is received within the collar and rotatable with resepct to the collar.

Abstract: Counterbalancing device in a rotary machine comprising at least one piston axially movable in a cylinder, such as a heat engine and equipped per cylinder with at least one rotating distributor. The distributor, on the one hand, is driven in rotation at the same angular speed as the crankshaft of the machine and in the opposite direction to it and, on the other hand, comprises a counterbalancing compensating mass, of at least one part of the primary inertia of the piston-connecting rod-crank assembly corresponding to the cylinder. Application to the counterbalancing of monocylindrical engines with a crankshaft of reduced bulkiness.

Abstract: A balancer structure for a three-cylinder engine for eliminating the vibration in the engine especially the vibration caused by an inertia couple about an axis perpendicular to the crankshaft of the engine. A countershaft is rotated at the same speed as the crankshaft but in opposite direction. Two counterweights are secured to the crankshaft corresponding to the first and third cylinders of both ends for balancing of reciprocating masses and rotating masses. A counterweight is secured to the crankshaft for balancing of reciprocating masses. At least two balancers are secured to the countershaft at both ends thereof.

Abstract: A balancer structure for a three-cylinder engine for eliminating the vibration in the engine especially the vibration caused by an inertia couple about an axis perpendicular to the crankshaft of the engine. A countershaft is rotated at the same speed as the crankshaft but in opposite direction. Two counterweights are secured to the crankshaft corresponding to the first and third cylinders of both ends. Each counterweight is opposite to the crank arm of the corresponding cylinder and perpendicular to the crank arm of the second cylinder. At least two balancers are secured to the countershaft at both ends thereof. Each balancer is opposite to the corresponding counterweight.

Abstract: A crankshaft of a V-6 internal combustion engine is provided with first and second end balance weights located at the front and rear end sections thereof. The crankshaft is further provided with first and second middle balance weights located near the first and second end balance weight, respectively, and a central balance weight located at the central section thereof, thereby establishing dynamic balance even between the adjacent main bearing journals of the crankshaft.

Abstract: The present application discloses a first-order balancer of an internal combustion engine comprising forward-rotating fly-wheels fitted on both ends of a shaft and allowed to rotate in the same direction as said shaft, backward-rotating fly-wheels fitted respectively on said both forward-rotating fly-wheels and allowed to rotate in the opposite direction from said both forward-rotating fly-wheels, forward-rotational counterweights placed on said both forward-rotating fly-wheels, and backward-rotational counterweights placed on said both backward-rotating fly-wheels and having a different weight from said both forward-rotational counterweights. According to the first-order balancer of an internal combustion engine of the present invention, vertical and horizontal first-order unbalanced moments arising in an internal combustion engine may be simultaneously balanced.

Abstract: Engines having multiples of two and three cylinders which are arranged in V configurations. These engines employ nonaligned crankpins and arbitrary included angles between cylinders. Through appropriate relationships between crankpins and the weight, residual linear inertial forces are substantially eliminated.

Abstract: A V-type internal-combustion engine comprises first and second cylinders arranged so as to form a V shape on a vehicle body frame, a piston slidably and reciprocally engaged in each of the first and second cylinders, and a crank shaft connected to the pistons by connecting rods. The crank shaft comprises a central web, side webs arranged on both sides of the central web, and two crank pins carried by the central and each of the side webs and connected to the connecting rods. The crank pins are arranged so that the rotary phases thereof with respect to the central axis of the crank shaft are offset by an angle .alpha. from each other.

Abstract: This invention is best suited for counterbalancing a single reciprocating (recip) member (such as a piston). A con rod interconnects a rotary crankshaft to a recip member. Two main counterweights are attached to the crankshaft and rotate therewith. Two coaxial contraweights rotate in the opposite direction from the crankshaft and at the same RPM as the crankshaft. The two main counterweights plus the two contraweights combine forces so as to balance the primary recip inertia forces. Two secondary weights are mounted on two parallel countershafts and they rotate at twice crankshaft RPM and in opposite directions from each other so as to balance the secondary recip inertia forces.A positive toothed driving means (such as gearing) is used to drive the two said countershafts from the crankshaft. The same gearing plus the two said countershafts are also used to assist in driving the two said contraweights so as to minimize the total number of shafts, bearings, and gears.

Abstract: Disclosed is an engine for motorcycles, having first and second engine blocks disposed in a form like V on the frame of the motorcycle. Pistons reciprocatably and slidably received in the engine blocks are connected to first and second crank pins of a crankshaft through respective connecting rods. Representing the included angle between the central axes of first and second cylinders for the first and second piston by .alpha., the rotational phase of the second crank pin is offset from that of the first crank pin by an angle .pi.-2.alpha. in the opposite side of the central axis of the first cylinder to the central axis of the second cylinder. A balancer weight is attached to that portion of the crank shaft positioned opposite to the first and second crank pins and on the bisector line of the angle formed between the first and second crank pins.

Abstract: A crankshaft mounted secondary shaking force balancer for multicylinder engines and the like in which eccentrically rotating balance weights carried on the crankshaft and arranged for substantial primary balance are combined in oppositely rotating groups of weights driven by stationary ring or sun gears and associated planetary gears to provide coacting rotating forces that combine to apply directly to the crankshaft a secondary shaking force reciprocating at twice crankshaft speed and available to balance equivalent oppositely directed shaking forces developed by the crankshaft connected moving components of the engine.

Abstract: A reciprocating engine, preferably a high speed internal combustion engine, includes means for reducing vibration.The engine has at least one piston, a connecting rod connected at one end to the piston and at the other end to a crankshaft. A pair of balancing links are pivotally mounted on the crankshaft and guide links constrain the balancing links to follow paths generally normal to the crankshaft axis and in opposition to the piston.The guide links extend in opposite directions and are attached to the balancing links and to a fixed point to balance out the vibrational forces of the engine.

Abstract: An even firing 90.degree. V6 four stroke cycle engine is provided with a single line balancer having a combination of primary balance weights and secondary Oldham coupling balancers rotating opposite crankshaft rotation which, combined with crankshaft counterweights, provide complete offsetting of the engine primary rotating unbalance couple together with offsetting of a large portion of the engine secondary rotating unbalance couple and leaving a small residual secondary unbalance couple for absorption by the engine mounting system.

Abstract: An internal combustion engine includes a crankshaft and a balancer shaft. The shafts are rotationally linked to one another, and the crankshaft is linked to a piston. The shafts carry weights to minimize the vibrations caused by the reciprocating motion of the piston. A reinforcing member has two enclosing portions, one for a bearing of each of the shafts, and integrally joins both of said enclosing portions. The reinforcing member is cast into the crankcase wall. Its material is stronger than the material of which the crankcase wall is made. Cracking and wearing of the crankcase wall, especially in the region between the two shafts, is reduced or eliminated, and the wall can be made thinner, and more reliably without cavities.