Customized stepping motor achieves 1.5 times more torque at high speeds

When the motor was replaced with one that produces torque at high speeds, vibration and heat became an issue...

Company Y, a manufacturer of automated biochemical analyzers, was working on developing a new model with the aim of shortening measurement cycle times, but had issues selecting a motor. Mr. M from the Product Development Department said the following:

"Automated biochemistry analyzers used in hospitals and testing institutions drip fixed amounts of reagent into test tubes containing samples. For this reason, the built-in motors need to move smoothly with little vibration. Heat generation can also be a problem because it can affect the samples, so it is also necessary to keep heat generation to a minimum. Furthermore, they must not emit any unpleasant noises.

With the new model we are currently developing, we are aiming to further improve the testing speed while taking these requirements into consideration. However, when we replaced the motor with a two-phase stepping motor that produces torque at higher speeds, vibrations were generated, affecting the accuracy of reagent dropping. What's more, the noise level also increased." (Mr. M)

Mr. M communicated these results to the motor manufacturer and asked for suggestions for other motors, but there were no suitable motors in their lineup.
Mr. M was at a loss as he had to start from selecting a new motor.

Custom proposals tailored to your operating conditions ensure low vibration and low noise!

Mr. M visited an exhibition to gather information and asked a person at SANYO DENKI CO., LTD. booth about a motor suitable for the device he was developing. Later, when he visited Company Y, the person in charge suggested customizing a five-phase stepping motor.

"SANYO DENKI CO., LTD. recommended customizations to suit our usage conditions, based on their highly efficient, low-heat motors. In response to our request for high torque at high speeds, they changed the windings to match the operating speed. They also proposed increasing the mechanical rigidity of the motor as a countermeasure against vibration and noise. These were proposals that other companies could not have made, so we were very grateful." (Mr. M)

Achieves 20% reduction in heat generation and 1.5 times torque increase at high speeds

Once the prototype was completed, Mr. Y immediately incorporated it into the new model and evaluated it.
"Compared to the motor used in the existing model, the new motor reduces heat generation by 20% and increases torque at high speeds by about 1.5 times. As a result, we were able to significantly reduce measurement times and complete an automatic biochemistry analyzer that meets our target performance. Because they proposed a good motor, we can expect to see performance improvements in the development of other equipment in the future." (Mr. M)

For more information about stepping motors, please see "What is a stepping motor? An explanation of its structure, types, usage (drive system and control method), advantages and features."​