First, the principle of vibration of the engine
during the working cycle of the engine, the piston velocity is very fast, and the speed is very uneven. The upper and lower dead center position, the piston velocity is zero, and the upper and lower dead center position of the highest speed. Repeated as do high-speed linear motion in the cylinder of the piston, must have a great inertial force on the piston, piston pin and connecting rod. Disposed on the link weights can effectively balance the inertial forces. But only part of the moving mass of the counterweight connecting rod linear motion participation, partial participation further rotation. In addition to the upper and lower dead center position, the various inertial force can not be completely balanced, the engine vibration is generated.
when the piston is moved up and down each time, the engine will produce about twice on a vibration, the vibration frequency and the engine rotational speed of the engine concerned. In theory called vibration, often used to describe a plurality of harmonic vibration of the vibration of the engine, wherein the vibration frequency and the same first-order vibration of the engine speed, the engine speed is twice the frequency of vibration is called second order, and so on, there are third-order , fourth-order vibration. However, the higher the vibration frequency, the amplitude of the smaller, second order or more negligible. First-order vibration accounted for more than 70 percent of the whole vibration is the main source of vibration.
Second, the way to solve the vibration of the engine
In order to eliminate the vibration, there are employed many methods, for example by reducing the mass of the piston lightweight moving parts, improving the rigidity of the crankshaft, a 90 degree clip v-twin engine arrangement angle and the like. But the way on the motorcycle engine is widely used to increase a balance shaft to resolve. Briefly balance shaft is provided with a shaft and an eccentric weight rotates in synchronization with the crankshaft, using a reverse eccentric weight vibratory force generated by the engine to obtain a good balance, reduce engine vibration.
Third, the balancing shaft Category
embodiment motorcycle engine balance shafts were of two kinds: double and single balance shaft balancing shaft. Two methods are the same in the works, butDETAILED different structure.
1. Double balance shafts embodiment
bis balance shaft drive chain transmission scheme using two balancer shafts rotate a balancer shaft in which the same engine speed, the first-order vibration of the engine can be eliminated; and the other balancer shaft speed 2 times the engine speed, the engine can eliminate second order vibration, can achieve the desired damping effect. Dual balance shafts way more complex, high-cost, large space occupied by the engine – as used on large displacement motorcycles.
Another arrangement bis balance shaft, two balancer shafts is at an angle to the cylinder axis arranged symmetrically rotate in opposite directions, with the same rotation speed of the crankshaft rotational speed for the first order of the reciprocating inertia force of the balance of the engine. For example the 276Q engine balance shaft, is disposed above.
2. Single balance shaft embodiment
single single balance shaft balancing shaft, the gear transmission mode to work, through the rotation of the crankshaft driven balancer shaft drive gear secured – GT; – GT balance shaft driven gear; balance shaft. Single balanced vibration can balance the total large proportion of first-order vibration, the vibration of the engine can be significantly improved. Balance shaft due to a single mode structure is simple, its small size, the small displacement and a single cylinder engines used widely.
Fourth, the application of the balancing shaft
In summary, the balancing shaft is to reduce vibration and to balance the motorcycle engine, to achieve reduction of the engine vibration and engine noise reduction, extending engine life, purpose of enhancing the comfort of the occupants. As a patent, it was first used by YAMAHA (Yamaha) motorcycle, received good results, balance shafts are used in the construction of each of Yamaha’s cars, which is also its features and selling points, in similar models, the it is undoubtedly the most quiet.