How to calculate the electronic gear ratio, how to calculate the gear speed ratio

The electronic gear ratio is to achieve different pulse equivalents by changing the sub-doubling of the electronic gear ratio.

The accuracy of the servo system is the encoder.

, but this is only a servo motor.

accuracy. In practice, different mechanical structures are connected, such as ball screws.

Worm gear and worm pair, the pitch, the number of teeth and other parameters are different, and the minimum unit of movement is moved.

The amount of motor rotation required is different.

The electronic gear ratio is an example of matching the number of motor pulses with the minimum amount of mechanical movement

The lathe uses a 10mm lead screw, then the motor rotates to move 10mm, and the motor needs to rotate 1 10,000 times for each movement.

If a 5mm lead screw is connected and the diameter is programmed, 1 5000 revolutions per movement is required, which is the function of the electronic gear.

This is the same as Fanuc's flexible gear ratio.

Here's an example of how to do it.

It is known that the resolution of the servo motor is 131072 pr and the feed of the ball screw is pb = 8mm.

1) Calculate the equivalent of the feedback pulse (how much does a pulse go)? lo=2) What should be the electronic gear ratio if the command pulse equivalent is required to be .

Electronic gear ratio

3) The rated speed of the motor is 3000rpm, what should be the pulse frequency?

fc=Answer:

1) Calculate the equivalent of the feedback pulse (how much does a pulse go)?

lo= 8mm/131072

2) What should be the electronic gear ratio of the required command pulse equivalent of ?

lo electronic gear ratio 1000=

3) The rated speed of the motor is 3000rpm, what should be the pulse frequency?

fc electronic gear ratio = 3000 60 131072

The formula for calculating the electronic gear ratio.

The speed of the gear and the number of teeth.

Inversely proportional, that is, the number of teeth with a large speed is less, the number of teeth with a small speed is more, the number of teeth of the driving wheel: the number of teeth of the driven version of the wheel = the right speed of the driven wheel: the speed of the driving wheel is mainly to determine the number of teeth of your driving wheel 900 revolutions, and then the number of teeth required for the driven wheel 120 revolutions can be calculated.

Or calculate the speed ratio, which is also the ratio of the number of teeth. For example, 120:900=4:30

Here 4:30 is the ratio of the number of teeth, that is, the driving wheel is 4n teeth, and the driven wheel is 30n teeth. Their speed is what you want.

Transmission ratio = number of driven gear teeth number of driving gear teeth = driving wheel speed driven wheel speed i=z2 z1=n1 n2 Remember a rule: the gear speed ratio of deceleration is greater than 1, and the gear speed ratio of speed increase is less than 1. Figuring out whether the gear is decelerating or increasing the speed ratio will not be inverted.

The formula for calculating the electronic gear ratio.

The gear ratio is calculated as i=z2 z1=n1 n2.

The gear ratio, known as the gear ratio in mechanical transmission, is expressed by i. i=z2 z1, z1 is the number of teeth of the active gear, and z2 is the number of teeth of the passive gear. If i>1, it is a deceleration; Conversely, i<1

It's the growth rate. That is, whether the speed of the passive gear is faster or slower than the active gear, it is called speed increase and deceleration respectively. Because in practical applications, most of them are decelerations.

Because the speed of the engine and the motor is very high, it is not suitable for the requirements of the dust brothers, and the speed must be reduced.

Definition of gear:

Gear modulus is defined as a basic parameter of modulus gear teeth, which is artificially abstracted to measure the scale of gear teeth. In gear design, the modulus is the decisive element that determines the size of the teeth. Different countries have different ways of defining modulus, the most typical of which are international standards (except for the British expatriate attack, the standards of other countries, including China, are in line with international standards) and imperial standards.

The electronic gear ratio is set according to the following method:

1. When the electronic gear ratio numerator is greater than the denominator, the maximum speed allowed by the system will decrease;

2. When the electronic gear ratio is not equal to the numerator and denominator, the positioning accuracy of the system may be reduced;

3. In order to ensure the positioning accuracy and speed index of the system, when supporting the digital servo with the function of electronic gear ratio, it is recommended to set the cavity of the electronic gear of the system to 1:1 to avoid the large disparity between the numerator and denominator of the electronic gear ratio of the system.

The electronic gear ratio is relative to the mechanical gear meshing, and the number of teeth of the gear pair. It is also a form of shaftless transmission that is often said at present.

Usually, mechanical transmission is to use a certain ratio of the number of teeth to achieve a fixed ratio of transmission. After the implementation of numerical control, the biggest change is the direct drive. The electronic gear ratio generally uses the angle encoder or the indexing function of the rotary encoder assembled by the rotary shaft, and uses the counting function in the numerical control or driving device to rotate the two shafts in a certain proportion, which is the electronic gear ratio.

If the pulse is not doubling, then the electronic gear ratio pulse equivalent means that actually 1 command pulse goes in millimeters, and now, 2500 input pulses go 5 millimeters, that is, 1 input pulse goes in millimeters, and this number multiplied by the electronic gear ratio is equal to the pulse equivalent.

"I want the gear ratio to be 1:1 and I need 10,000 pulse motors to make one revolution" I don't think it's possible. Do you see this need from **, or is it a topic that you imagined yourself?

Of course not, the molecule of the electronic gear is actually the number of pulses required by the motor, the denominator is the number of pulses received by the driver, and the resolution is the number of pulses required by the motor to turn a turn, if you want 10,000 pulses to turn a turn, it must be that the pulse accepted by the driver is 10,000, but the pulse required by the motor is the resolution of the encoder 131072 just compare these two. Finally get a gear ratio, but it's certainly not 1:1

The numerator is the actual distance of motion and the denominator is the number of pulses emitted by one rotation of the motor.

The maximum frequency of the pulse interface is 200kHz, corresponding to the maximum speed of 3000 revolutions per minute, so that the positioning module can play the highest speed of the servo.

Motor speed (3000rpm) 60 = pulse frequency (200000Hz) *numerator denominator) Servo resolution (131072).

The electronic gear molecule is about 4096 and the electronic gear denominator is 125

The result of this setup is 4000 pulses per revolution, and a frequency of 200kHz corresponds to a speed of 3000rpm.

One revolution of the lead screw is exactly 10,000 pulses. The resolution of the encoder is 2500 pulses per revolution. That's how it is calculated, 1 mm is equal to 1000 microns, and 10mm lead screw your system can be accurate to microns.

The gear speed ratio calculation method includes the definition calculation method, the gear train calculation method, the gear train calculation method, etc.

1. Define the calculation method.

Reduction ratio = input speed output speed, the ratio of the connected input speed to the output speed, if the input speed is 1500r per min and the output speed is 25r per min, then the hall scale reduction ratio is i = 60:1.

2. Calculation method of gear train.

Reduction ratio = number of driven gear teeth number of driving gear teeth (if it is a multi-stage gear reduction, then the number of driven gear teeth of all meshing pairs of gear sets The number of driving gear teeth, and then multiply the results obtained.

3. Gear train calculation method.

Reduction ratio = driven wheel diameter He Chun driving wheel diameter.

Reduction ratios must be common sense:

First of all, you determine the type of reducer you want, then determine the input power and the torque required for the output, and then calculate the speed ratio of the reducer according to the speed of the input shaft and the speed of the required output shaft. The working condition coefficient is determined according to the actual usage such as daily working time, shock load, switching frequency, etc.

The applicable power of the reducer model selection and precautions is usually the applicable power of the servo model on the market, the applicability of the reducer is very high, and the working coefficient can be maintained at the above, but the selection can also be decided according to their own needs. The output shaft diameter of the servo motor should not be greater than the maximum shaft diameter on **.

If the torque calculation work, the speed can meet the usual operation, but when the servo is fully output, when there is a deficiency, we can do the current limiting control on the drive on the motor side, or do torque protection on the mechanical shaft, which is very necessary. <>