| With the development of modern science and technology, machinery industry hasrapid development, and the rotating speed has also rapid improvement. Therefore, peoplehave increasingly high requirements to the dynamic characteristics of the mechanicalparts. In the mechanical transmission, the gear transmission is an important part of it andit is also a most, playing an indispensable role in the national construction. In theautomotive, marine, aviation, machine tools, construction machinery, mining andmetallurgical machinery and other mechanics use gear transmission. The gear box ismade up of the gears, shafts, bearings and a box body. Some studies have found, thegearbox is one of the main noise source of the machine, and the noise of geartransmission is the main source of noise of gearbox. In general, in the gear design gearperformance, more consideration of people is the load capacity and fatigue life, very littlevibration and noise of the gear drive as the primary consideration. Various machinewhich adopts gear transmission has friction and vibration problems between the teeth, sothe research has very important significance to control the vibration and noise of geartransmission.Recent years with the advent of the special gear, many designers in the gear designhave many methods to reduce gear noise. Usually people only improve the parameters ofthe gear, gear processing technology, precision of the gear, gear box, gear, gear shapematerial installation accuracy, gear tooth surface and gear structure to control thevibration and noise of gear. Little of the friction between tooth gear in the vibration noiseis considered.This paper is tested by vibration experiment of friction and analyzes frictionalvibration of gear. Getting the dry friction and lubricating the spectrum after throughexperiments, and the frequency spectrum reaches the following conclusions:1. Through the theoretical analysis of gear, tooth surface friction phenomenon is real,and it is an important part of gear vibration excitation source.2. The cantilever beam of dry friction experiments show that friction is caused byvibration, at the same time, noise can be accompanied by the phenomenon.3. In gear transmission, if the vibrational frequency which is caused by friction hasthe relationship between the integer times with meshing frequency, resonancephenomenon will happen, causing the energy superposition, releasing high vibrationnoise.4. In experiments, applying the oil makes the friction surface producing "micro convex body oil film elastic support effect ", this layer of oil film can improvethe vibration which is caused by friction. |
