http://v3.espacenet.com/textdoc?DB=EPODOC&IDX=IT1243824&F=0 Patent number: IT1243824 Publication date: 1994-06-28 Inventor: BORDI MASSIMO Applicant: DUCATI MECCANICA SPA Classification: - international: B60K - european: Application number: IT19900021690 19901010 Priority number(s): IT19900021690 19901010 Abstract of IT1243824 A single-cylinder engine 1 comprises a sump 2 in which a cylinder 3, in which a piston 4 moves connected to a normal connecting rod 5 associated with an engine shaft 7, is defined, at least partially. According to the invention, a second connecting rod 8 is associated with the engine shaft 7; this is suitable for operating on an oscillating balancing mass 9 arranged inside the sump 2 and hinged to the latter at 14; this mass 9 has a substantially elongated conformation and, when the engine 1 is running, its longitudinal axis W is arranged substantially parallel to that of the connecting rod 8 (should be 5) operating on the piston 4, as at least one crankshaft flywheel 30 acting as a counterweight is associated with the engine crankshaft 7. doc 1 DISCRIZIONE *Shape object of introduces comprising invention a single cylinder motor crankcase in which and defined, at least partially, a cylinder where a piston connected to a usual connecting rod associated to a drive shaft moves.* *Like and famous, in a single cylinder motor (like, in a generalized manner, in every type of motor) you and it needs it to compensate the sollecitiazioni, agents on the drive shaft and on organs associate, provoked to you from usual forces alternated rising during the motion of piston.* *Solutions apt are various notes to obtain the cited compensation over, that is apt to obtain one opportune equilibratura of the motor.* *One of such solutions previews a cinematic device associated the drive shaft comprising of the rotismi (of which at least one connected with the drive shaft) it connects to you between they by means of similari chains or organs.* *Such soluzionie introduces various disadvantages.* *Innanzittuto, penalizes the power distributed from the motor poiche, just for its realization shape, limits the number of turns raggiungibilie from the motor.* Inoltre, la soluzioni suddetta risulta generare, nel *Moreover, the solutions aforesaid turn out to generate, in operation of the motor, rumorosita one not negligible always tied its realization shape.* *Finally, such realization turns out complex and entails increased weights.* *Other solutions to obtain the balance of the motor are cited.* *Such solutions, however, do not allow to compensate in optimal way the above cited rising vibrations on the drive shaft. In particular, such vibrations are subdivided in various different members orders, the solutions notes, also allowing to compensate in less effective way for the vibrations of the first order, they do not concur to compensate in some way (or way a lot softly) those of according to order. Since also these last vibrations they can, with the use of the motor, to damage in serious way the members of final questions, the lack of whichever they compensation for entail obvious problems.* *In a generalized manner, moreover, the famous systems are expensive, involve more use of the power generated from the motor, increases the consumption of fuel and are complicated to make.* *Therefore the scope of the present invention and that one to offer a device for the balance of a single cylinder motor of the cited type that it exceeds the disadvantages of the other noted solutions.* *In particular, scope of the invention and that one to supply a device of the cited type that is reliable and that allows to take advantage of acquaintances and members wide you notice cosi concurring one its fast realization and with contained costs.* *One other scope and a that one to supply a cited device of the type that it concurs to take advantage of to the maximum the power (theoretical) of the motor and that it allows to catch up, during operation of this last one, the higher revolutions of the motor.* *Ulterior scope and a that one to realize a device of the cited type that it has one reduced weight, blocks contained and one rumorosita much contained one.* *An other scope and that one to offer a device of the indicated type over that it is of simple realization.* *These and other scopes that will turn out obvious to the expert of the branch come caught up from a device for the equilibratura of a single cylinder motor of the type piu over cited, characterized from the fact that to the drive shaft and associated a second connecting rod apt to operate on one oscillating quilibratrice mass dispost within Carter and hinged to this last, such one mass having conformation substantially lengthened and introducing, during the fuzionamento of the motor, the longitudinal axis arranged substantially parallel to qello of the operating connecting rod on the piston.* *For a greater understanding of the present invention it is enclosed a.tito it pure exemplificativo, but not limitativo, the following design, in which:* *the figure 1 and one seen from the high, in section cross-sectional, of a motor to which and associated dispositivio second an invention; and figure the 2 and one section second trace II-II of figure 1.* *With reference to the cited figures, a single cylinder motor 1 comprises engine case 2 in which is mounted a cylinder 3. In this last one it moves, of alternated motion, a piston 4 moved from one typical connecting rod 5 on a crank pin 6 to a drive or main crankshaft 7. This attached to at least one eccentric mass (or flywheel counterweight) 30 (two flywheel counterweights in figure 2).* *According to the invention, crankshaft 7 has in motion a second connecting rod 8 operating on one balance weight 9 hinged to crankcase 2.* *Such mass 9 (having substantially a shape similar to that of one of the connecting rods 5 and 8) it acts to compensate the oscilliatations/vibrations, in particular of the first and the second order, exerted on crankshaft 7 and caused by the forces alternated rising during the movement of the piston in particular, to crankpin 6 and associated with the big end 8A of second connecting rod 8.* *This last and bound one through a wristpin/joint 11 to outer end 12 of balance link 9, the other end 13 of this last one being hinged to crankcase 2 through one pivot pin 14.* *In such a way, the second connecting rod 8, balance link 9, pivots 6, 11 and 14 define one oscillating triangle that allows it to absorb the oscillations/vibrations generated from the reciprocating motion of piston 4.* *To the aim of having a fair distribution of the weights on oscillating balance link 9 and, in particular, in order to maintain if possible the last center of mass of this next one to the K axis of second connecting rod 8, the extreme end 12 of mass 9 and conformed substantially to C and it introduces two portions parallels 16 and 17 (one, the 16 coinciding with a body 18 of having balance link 9 longitudinal axis W) connected from disposed a cross-sectional part 19 towards side 20 of said 9 balance link where and present a semicircular part 21 that increases the weight of extremity 12 and improves movement of the center of mass towards the K axis.* *Moreover, the maintained aforesaid center of mass and also on the plan of job of connecting rod 5 to fine to avoid the birth of unbalanced couples.* *During the operation of motor 1, the piston moves in reciprocating motion in cylinder 3.* *During such motion, the second connecting rod 8 makes in motion mass 9 that oscillates around hinge 14 and that it is maintained, with its longitudinal axis W, substantially parallel to connecting rod 5.* *The connecting rod assembly 8 - balance link 9 generates a force on crankshaft 7 whose member, on one slowly orthogonal to that one on which the piston moves, sum with that one generated, in its movement, from piston 4 on such slowly; in such a way one turning out is generated and counterbalances from crankshaft flywheel/counterweight 30.* *Such turning out it represents the oscillations of the first order generated on crankshaft 7 from piston 4 and the aforesaid counterbalance it allows the equilibrium of such oscillations.* *from the connecting rod assembly 8 - hinge 9 on one flat parallel to that one of the motion of the piston is made up with the urge/force rising along connecting rod 5 so as to to give one turning out substantially zero. Such turning out it represents the oscillations of according to order the generated ones on crankshaft 7 during the motion of piston 4, oscillations that therefore are zero (or however negligible).* *A single cylinder motor using the second invention turns out very balanced.* *The device second the invention and is of simple manufacture, and reliable and it involves a sensible increase of the weights and of it blocks of the motor to which and junior clerk (doesn't obstruct anything?).* STATEMENT *1) Device for the balancing of a single cylinder motor in particular of the type comprising a crankcase in which and, at least partially, a cylinder where a typical connecting rod associated to a crankshaft moves a piston connected to one, feature/distinguished from the fact that to the crankshaft (7) and associated a second connecting rod (8) apt to operate on a balancing link (9) within crankcase (2) and hinged (in 14) to this last one, such mass (9) having conformation/compliance substantially lengthened and introducing, during the operation of motor (1), the longitudinal axis (w) disposed substantially parallel to that one of the connecting rod (5) operating on piston (4).* *2) Device of which to statement 1, characterized from the fact that to the crankshaft (7) and at least associated a flywheel/counterweight (30) acting as a counterbalance.* *3) Device of which to the statement 1, characterized from the fact that the second connecting rod (8) and bound to the crankshaft (7) through a crankpin (6) to which the connecting rod (5) of piston (4) is attached.* *4) Device of which to the statement 1, characterized from the fact that the balancing link (9) and associates, to one extreme end (12), through a pivot (11), to the second connecting rod (8) and through a stationary pivot (14) and to crankcase (2), said balancing link (9), the second connecting rod (8), the aforesaid pivots and that one pivot (6) that constrains such connecting rod (8) to the crankshaft (7) defining a oscillating triangle.* *5) Device of which to the statement 1, characterized from the fate that the center of mass oscillating and at least next to the axis (k) of second connecting rod (8).* *6) Device of which to the statement 4 and 5, characterized from the fact that the extreme end (12) of associated balance mass (9) to the second connecting rod (8) has weight greater in respect to remaining parts of the body (18) of balance (9), this agreeing to carry the center of mass of this last one in correspondence of the axis (k) of said second connecting rod (8).* *7) Device of which to the statement 6, characterized from the fact that the extreme end (12) is connected to the second connecting rod (8) and conforms balance link (9) substantially to "C" and it introduces two rectangular portions (16, 17), one coinciding with body (18) of the aforesaid mass, connected from an arranged cross-sectional part (19) to the extreme end (20) of balance link (9), between said rectilinear portions being placed the pivot (11) for the tie between connecting rod (8) and balance link (9), in correspondence of the aforesaid extreme end (20) being a semicircular part/shape (21).* *8) Device of which to the statement 1, characterized from the fact that the center of mass vibration of the balance link (9) and place it on the plan of job of the associated main connecting rod (5) to piston (4).*