Bearing classification and how to reduce noise - Butterfly Kay mechanical bearings

Bearings can be divided into sliding bearings and tumbling bearings. Sliding suction movement is more stable, less vibration, low snoring, and more based on the detailed structure of its own design. During this time, generally speaking, the controversial bearing may constitute a friction probe due to unsatisfied lubrication at the time of starting, and a large squeaking occurs and the bearing is scratched. Therefore, it is not necessary to clear the bearing in an important drive shaft of a general machine tool. . The priming control of the tumbling bearing is mainly introduced below:

Rolling bearings generally consist of four parts: the inner ring of the outer ring, the roll body, and the retainer. Rolling bearing hum and squeak control methods can be summarized as follows:

(1) Slamming and manipulation caused by the oscillation of its own structure. There is a roll body in the bearing. It rolls on the raceway between the rings in the table. The inner ring and the inner ring are deformed after being stressed. During high-speed rotation, the radial and axial oscillations may occur in both the internal and external directions, and the axial oscillations are relatively intense. These oscillations are called elastic oscillations. When the roll body passes through the force zone, the elastic deformation of the roll body increases. The elastic oscillation of the inner and outer rings adds little to the axial and radial bearing bearing oscillations of the bearing. When the w between the inner and outer rings is larger, this oscillation is in resonance with the tortuous oscillations of the drive shaft and gears, or other rotating bodies, or changes oscillations; radiation radiates intense sound absorption. Control the noise caused by the oscillation of its own structure. Its useful approach is to lift away the pumping stiffness. Reduce the deformation, that is, over the adjustment of the release direction and axial alignment, increase the preload, can reduce the bearing oscillation and noise.

(2) The relationship between the bearing and the squeaking noise, bearing noise and its own structure. Different types of bearings, the buzzing of different tumbling bearings generally in accordance with the shape of the tumbling and bearing manner classification. The ball bearing's roll body is spherical. The point contact between the ball bearing and the rolling over is: Roller bearing roll body Embossed column shape. Between roll body and raceway is line contact two roll body In addition to ball and eye column shape There are inverted shape or round shape, etc.: the bearing can be divided into i sentence heart bearing and radial thrust bearing in the bearing manner. The former can only accept radial force, while the latter can accept both radial force and bearing. Inside axial force, the roll body is the primary component of the tumbler in the roll bearing. The shape of the roll body is different, and the relative motion between the table and the inside is different during operation. Different types of bearings have different squeaks. A unit once used f7520, 1)7518 round insert roller bearings, 220, 218 radial ball bearings and 4620, 46218 radial thrust ball bearings, mounted on the C6150 lathe as a front and rear bearing, at a speed of 1250r/min. experimenting. According to the test, the I-1 heart ball bearing and centripetal thrust ball ball bearing are 9 dB (A) lower than the figure cone bearing noise. It can be seen from this point that, considering the reduction of bearing noise, the selection of ball bearings is superior to other types of bearings.

(3) The accuracy of the bearing and the error in the shape of the squeak. It has been proved through tests that the accuracy of the roll body, the inner ring and the outer ring of the bearing is improved, and the bearing noise generally decreases. The data shown in Table 12-1 is a combination of "7520 and 9751. Single row roller bearings with different precisions of table, inner ring and roller. It is mounted on (6150) all-shaft front and back of the machine. The spindle speed is 1250r/. Obtained under min conditions.

From the table, it can be seen that as long as the roller tip is improved, the bearing noise can be reduced by 7 to 10 dB (A). Roller accuracy is the primary factor affecting bearing sound.