When the raceway sound of the electric spindle bearing is running, a continuous sound is emitted by the rolling elements rolling on the raceway surface. Generally speaking, it is a unique sound that occurs in all-electric spindle bearings. The general bearing sound is the raceway sound plus other sounds. The raceway sound of the ball bearing is irregular, the frequency is above 1000Hz, and its main frequency does not change with the rotation speed, but its total sound pressure level increases with the acceleration of the rotation speed. For a bearing with a loud raceway sound, the sound pressure level of its raceway sound decreases with the increase of viscosity; while for a bearing with a small raceway sound, its sound pressure level changes from decreasing to about 20mm2/s when the viscosity increases. to increase. The more rigid the housing, the lower the total sound pressure level of the raceway sound. If the radial clearance is too small, the total sound pressure level and dominant frequency of the raceway sound will increase sharply with the reduction of the radial clearance. The methods of controlling the raceway sound are as follows: choose low-noise motorized spindle bearings, that is, bearings with small waviness, and carefully select the conditions of use. The sound of the raceway often affects the noise of the entire machine, and reducing the sound of the raceway can reduce the noise of the entire machine.
Impact sound of rolling elements and its control method: When larger type ball bearings or cylindrical roller bearings run at low speed under pure radial load, due to the small centrifugal force of rolling elements, the rolling elements in the non-load area will be impacted, and maintained. rack or raceway and make noise. But as the revs increase, the noise disappears. The control methods for the impact sound of the rolling elements are: reducing the radial clearance appropriately and using an electric spindle bearing with a cage with a reasonable structure and a flexible material.
During the motorized spindle bearing rotation, the bearing is continuously worn and failed due to frictional resistance. The resistance that hinders the rotation of the electric spindle bearing consists of rolling friction, sliding friction, and lubricant friction. Rolling friction occurs when the rolling elements roll on the bearing raceway; sliding friction occurs on the guide surfaces of the rolling elements in the cage, the guide surfaces of the rib of the cage, and the end faces of the rollers and the rib of the ring in the roller bearing; lubrication The agent friction consists of the internal friction of the lubricant at the contact point and the stirring and extrusion of the lubricant. Therefore, the resistance to the movement of the resistance bearing is the sum of the above three frictions. The purpose of lubrication is to avoid direct contact between raceways, rolling elements, and cage metals through grease and its lubrication method, reduce frictional heat and minimize frictional resistance, thereby reducing wear, preventing rust, and prolonging its use. life.
About 80% of the bearings are lubricated with grease. There are many types of bearings that are sent to users after being greased in the bearing factory. Therefore, some people refer to the grease as the fifth largest part of the bearing except for the four parts of the inner ring, the outer ring, the rolling body, and the cage.
Contact us:
E-mail: sales@tedin-bearing.com