About the improvement of bearing the preset, how much do you know?
by:Waxing2020-11-15
About the improvement of bearing the preset, how much do you know?
Source: bearing | last updated: - 2020
06 -
24 about the improvement of bearing the preset, how much do you know?
About the improvement of bearing the preset determine the optimization of objective function and limit bearing.
Common objective function is the fatigue life is very long (
The basic dynamic load rating is very big)
, long wear life (
Small oil film thickness is very big)
And friction torque is low and so on.
Because the work environment requirements as far as possible the use of small diameter of steel ball bearing, space restrictions to make the comparison of the inner and outer diameter of the bearing and eccentric, therefore should be considered to keep the strength of the eccentricity (
The area of thin thin bearing)
Means that the outer ring and inner ring in large eccentric must have a certain thickness.
The thickness and the diameter of steel ball and ball set the diameter of the pitch circle.
Because of the steel ball diameter, pitch diameter of the hemisphere group in the expression of basic dynamic load rating is a variable.
At the same time, considering the fatigue damage and bearing used in test requirements, choose the optimization goal: constraints bearing the basic dynamic load rating is bigger.
The processing of design variables in the design of bearing, the number of steel ball Z as integer variables.
Dw generally should choose according to the standard steel ball diameter, the discrete variable.
The ball group Dpw pitch diameter for continuous variables.
Therefore, the optimization design of the bearing is mixed variable optimization design.
Ball diameter Dw had a great influence on the result.
The diameter of the standard of qualified steel ball is only five.
0 and 5.
5mm。
Don't have much choice.
Therefore, in the process of optimization, Dw is based on continuous variables for processing of steel ball diameter, it depends on the outcome of the optimization.
If is not too big difference with standard values, please select the most close to the standard values.
If the difference is too big, please customize according to the results of the optimization to the manufacturer.
In addition, full bearing assembly is also a problem.
Considering the bearing force only in 1/2 area, USES in the load bearing area of the annular passage at the bottom of the filling method of steel ball in the hole.
After the calibration of measurement and control unit of the input signal U, adjust the measurement and control unit of magnification to display the corresponding vibration displacement A (
Lm)
。
If the use of acceleration sensor, the sensor in theory the output power of Q to Q = AX2D = vXD = aD (
10)
Among them: D is acceleration sensor voltage sensitivity, mV/g;
V is vibration velocity, m/s;
A is vibration acceleration g (
1 g = 9。
8m / s2)
。
In the case of know the sensitivity of the sensor, the use of (
10)
Calculation and vibration displacement, velocity and acceleration of the three parameters corresponding to the sensor output power.
Acceleration sensor using acceleration parameters calibration instrument is more intuitive, more easily.
To the calibration object is measurement and control unit, not including sensors.
Calibration accuracy depends on the reliability of the sensor sensitivity technical specifications, as well as to monitor the accuracy of the input signal of the instruments and apparatus.
Introduction of bearing bearing (
GB / T 276 -
1994).
The original list of radial ball bearing is the most widely used rolling bearing.
It is the feature of low friction resistance and high speed.
It can be used to bear radial load at the same time or the radial and axial load of mechanical parts.
It can also be used to carry axial load of mechanical parts, such as small power motor, automobile and tractor gearbox, machine tool gear box, general machinery, tools, etc.