Drive devices that rotate materials and tools are indispensable for processing equipment such as cutting machines and grinders. Spindle motor is one of the rotary drive devices.

In this article, we explain about the spindle motor, which is a rotary drive device. In addition, we introduce the features of Seiko Instruments' spindle motors, which are developed based on the precision technology cultivated in watch manufacturing and abundant experience over many years.

The spindle motor is a rotary drive device with a simple structure.

First, let's check the outline of the spindle motor. Spindle is an English word that means "rotary axis" or "mandrel". When used in the field of machining, it mainly refers to an abbreviation for "spindle unit," which is a device that gives accurate rotational motion to a rotating object.

Many rotary drives are composed of multiple parts such as motors, gears, and belts, and the structure tends to be complicated and the size tends to be large. On the other hand, the spindle motor uses a motor that integrates the power source and the rotating part, and its major feature is that its structure is simple.

Spindle motors, which have a simple structure, have the same capabilities as other rotary drives, but are smaller in size.　 Furthermore, since it does not require space other than the axial direction, it is possible to install many spindles in parallel.

The main uses of spindle motors are power sources such as drilling, cutting and grinding tools, and tools such as drills are attached to the tip. It can also be used for machining robots, and is used for machining high-precision parts by taking advantage of its high controllability.

As a product lineup of spindle motors, various products are available depending on the rotation speed, output, size, lubrication method, etc., and it is possible to select the product according to the application.

Performance required for spindle motors

Due to the small size of spindle motors, there is increasing demand in various industries within the manufacturing industry. Specific examples include ultra-precision machining areas such as machine tools, semiconductors, and electronic component processing machines.

In order to meet the demands of the industry and expand the field of activity, in addition to high control accuracy, versatility that can be applied to various equipment and high environmental performance for social responsibility are required.

In recent years, demands for high-mix low-volume production have increased, and demand for spindle motors with a wide range of applications for one spindle is increasing.

Features of Seiko Instruments' high-precision high-frequency spindle motors

We are developing high-precision high-frequency spindle motors to meet a wide range of demands centered on the precision machining field.　 Based on the technology cultivated through many years of precision processing of wristwatches, we continue to improve its performance by adopting it in the internal grinder developed by us.

Realization of high rigidity and high precision rotation by optimizing structural design

Seiko Instruments' spindle motors ensure high rigidity by increasing the diameter of the rotating shaft, while achieving high rotational accuracy at high speeds by optimizing the bearing design and lubrication circuit.
With these characteristics, it is one of the great strengths of our spindle motors that it can handle from rough machining with a high machining load to finish machining that requires high machining accuracy with one spindle.

High reliability due to our unique inspection and assembly system

Precision parts have high demands for machining accuracy, and high reliability is also required for machining equipment. Seiko Instruments has achieved high reliability by adopting inspection systems such as vibration analysis by FFT (Fast Fourier Transform), operating temperature monitoring, and balance correction, in addition to its original assembly technology.

Flexibility with various tool interfaces

In order to utilize spindle motors in a wide range of industries, high versatility that can be attached to various equipment is important. Seiko Instruments supports various interfaces (tool mounting methods) and can be selected as an option according to the application.

For users who are already using spindle motors made by other companies, including those made overseas, if the interface does not match, it will be necessary to modify the equipment or replace the equipment. We can customize to various interfaces, and it is relatively easy to replace only the spindle motor without modifying or replacing the existing equipment.

We also accept customization consultations if the standard lineup does not suit your needs. For example, if higher machining accuracy and load capacity are required, Seiko Instruments' hydraulic and air static pressure bearing spindle design and manufacturing technologies can be utilized.

Cost and performance optimization with simulation technology

The use of simulation technology at the design stage is advancing in various industries, and Seiko Instruments also uses structural analysis and simulation technology when designing spindle motors.

By performing simulation analysis in advance of vibration characteristics, stress concentration on each part, looseness, effect of temperature rise, load during machining, etc., early confirmation of problems, shortening of development speed, and improvement of product reliability are realized.

In addition, by checking the simulation results while changing the conditions that affect performance and cost, performance and cost optimization is realized at the design stage.

Environmental load reduction by optimal design of lubrication circuit

Seiko Instruments' spindle motors have been devised with a lubricating air circuit inside the main body to reduce the amount of lubricating oil and air used during processing.

Reducing consumption not only has the effect of reducing the impact on the environment, but also has the effect of reducing costs by reducing materials.

Summary

Since spindle motors are small and highly accurate among rotary drive devices, demand is expected to increase more than ever in industries that require high machining accuracy such as precision parts.

Seiko Instruments' spindle motors not only have high processing accuracy, but also have high reliability due to our unique inspection system and high versatility that can be easily replaced with existing equipment.

If you are looking for a high-precision and versatile high-speed spindle motor, or if you have any questions about the spindle motor of your own equipment, please contact us.