On the other hand, when the engine inertia is bigger than the strain inertia, the electric motor will need more power than is otherwise necessary for the precision gearbox particular application. This increases costs because it requires paying more for a motor that’s larger than necessary, and since the increased power consumption requires higher operating costs. The solution is to use a gearhead to match the inertia of the motor to the inertia of the load.
Recall that inertia is a measure of an object’s level of resistance to change in its motion and is a function of the object’s mass and shape. The greater an object’s inertia, the more torque is required to accelerate or decelerate the object. This implies that when the load inertia is much larger than the motor inertia, sometimes it could cause excessive overshoot or increase settling times. Both conditions can decrease production range throughput.
Inertia Matching: Today’s servo motors are generating more torque in accordance with frame size. That’s due to dense copper windings, lightweight materials, and high-energy magnets. This creates higher inertial mismatches between servo motors and the loads they want to move. Using a gearhead to better match the inertia of the electric motor to the inertia of the load allows for using a smaller electric motor and results in a more responsive system that’s easier to tune. Again, that is accomplished through the gearhead’s ratio, where the reflected inertia of the strain to the engine is decreased by 1/ratio^2.
As servo technology has evolved, with manufacturers generating smaller, yet better motors, gearheads are becoming increasingly essential companions in motion control. Locating the ideal pairing must consider many engineering considerations.
So how really does a gearhead go about providing the energy required by today’s more demanding applications? Well, that goes back again to the basics of gears and their capability to modify the magnitude or path of an applied force.
The gears and number of teeth on each gear create a ratio. If a engine can generate 20 in-pounds. of torque, and a 10:1 ratio gearhead is mounted on its result, the resulting torque will be close to 200 in-lbs. With the ongoing emphasis on developing smaller footprints for motors and the equipment that they drive, the ability to pair a smaller motor with a gearhead to attain the desired torque result is invaluable.
A motor could be rated at 2,000 rpm, but your application may only require 50 rpm. Trying to run the motor at 50 rpm might not be optimal based on the following;
If you are working at an extremely low velocity, such as 50 rpm, as well as your motor feedback resolution is not high enough, the update price of the electronic drive could cause a velocity ripple in the application. For instance, with a motor feedback resolution of just one 1,000 counts/rev you have a measurable count at every 0.357 amount of shaft rotation. If the digital drive you are using to control the motor has a velocity loop of 0.125 milliseconds, it will look for that measurable count at every 0.0375 amount of shaft rotation at 50 rpm (300 deg/sec). When it does not observe that count it will speed up the engine rotation to think it is. At the speed that it finds the next measurable count the rpm will end up being too fast for the application form and the drive will gradual the motor rpm back off to 50 rpm and the complete process starts yet again. This constant increase and decrease in rpm is exactly what will trigger velocity ripple in an application.
A servo motor working at low rpm operates inefficiently. Eddy currents are loops of electric current that are induced within the motor during procedure. The eddy currents in fact produce a drag power within the electric motor and will have a larger negative effect on motor performance at lower rpms.
An off-the-shelf motor’s parameters may not be ideally suited to run at a low rpm. When an application runs the aforementioned motor at 50 rpm, essentially it isn’t using most of its offered rpm. As the voltage constant (V/Krpm) of the engine is set for a higher rpm, the torque continuous (Nm/amp), which is definitely directly linked to it-is certainly lower than it requires to be. Consequently the application requirements more current to operate a vehicle it than if the application had a motor particularly designed for 50 rpm.
A gearheads ratio reduces the motor rpm, which explains why gearheads are occasionally called gear reducers. Using a gearhead with a 40:1 ratio, the electric motor rpm at the input of the gearhead will end up being 2,000 rpm and the rpm at the output of the gearhead will become 50 rpm. Working the engine at the bigger rpm will enable you to prevent the worries mentioned in bullets 1 and 2. For bullet 3, it allows the look to use much less torque and current from the motor predicated on the mechanical advantage of the gearhead.