Skip Motor

Introducing the Skip Motor

See us at:

TECHNO-FRONTIER 2024
MOTOR TECH JAPAN

July 24-26, 2024

Tokyo Big Sight

www.jma.or.jp/tf/

A new type of electrical motor was built, tested and patented, that works in discrete steps comparable to step motors. It has many benefits, the most notable are: low price, no need for rare earth metals, few parts and high rotational resolution. USA Patent 10,468,958 was issued on November 2019.
The motor was named Skip Motor.
新しいタイプの電気モーターをご紹介したくご連絡いたします。これは、私が開発・テストし、特許を得たモーターで、ステップモーターに相当する分散ステップで動作します。このモーターには多くの利点がありますが、中でも特筆すべき利点は、低価格であることです。レアアース金属を必要としませんし、少ない部品で高回転の分解能を有します。2019年11月に米国の特許No.10,468,958として認可されました。このモーターを、Skip Motor[スキップモーター]と名付けました。
The construction and performance of the skip motor:
スキップモーターの構造と性能は、以下の通りです:
  • The skip motor needs only standard steel (0.2% Carbon) and copper wires for the construction, no ball bearings, no rare earth metals. Simple digital chip drive.
  • Assembly is simple, drop-in parts. Can be assembled from stock components to fulfill orders for different skip sizes and voltages.
  • Skip size may be 2-0.1 degrees depending on the mechanical gap between the stator and rotor. That is 200-4000 steps per revolution. This alleviates the need for a gear in many applications.
  • The skip motor is a bit noisy during skips, with high frequency clicks that may be shielded with foam.
  • スキップモーターは、標準スチール (カーボン0.2%)と銅線のみで構成されています。ボールベアリングやレアアース金属は必要ありません。シンプルなデジタルチップが駆動します。
  • 組み立ては、シンプルな差し込み部品で行います。在庫部品からの組み立てで、異なるスキップサイズおよび電圧に対応できます。
  • スキップサイズは、ステーターとローター間の機械的なギャップに寄りますが、2-0.1度です。つまり、一回転につき200-4000ステップになります。これにより、多くのアプリケーションにおけるギアの必要性が軽減されます。
  • スキップ中のスキップモーターは、高周波のクリック音を伴いますが、これはフォームで遮蔽できると思います。
Skip Motor Audio Testing
Screenshot of the acoustic spectrum analyzer

The yellow line is the background noise. The red line is the peak signal while the motor was working. The graph shows that most of the noise is above 1000 Hz, and therefore easy to shield.

Steps-Per-Revolution Calculator

Skipping Motor Comparison

 
DC Servomotor
Stepping Motor
Skipping Motor
Cost
 
 
 
Manufacturing cost
Very high
High
Very low
Controller cost
Very high
One chip
One chip
​Requires rare earths?
Yes (if brush-less)
Yes (for locking)
No (both locking/free)
 
 
 
 
Manufacturing logistics
 
 
 
Shipment ready stock
Different controllers / position sensors for different resolutions
​Different product lines for different resolutions
Can be assembled to achieve different skip resolutions with a stock of rotors having different gap dimensions.
Voltage flexibility
Pre-assembled with coils for a specific voltage
Pre-assembled with coils for a specific voltage
Drop-in coils for different voltages
 
 
 
 
System assembly
 
 
 
Requires fine alignment
Yes
Yes
No
Size / space taken
​High
​High
Low
Requires a gear for fine positioning
No
Yes (or micro-stepper drive electronics)
No
Needs a position sensor
for precise positioning
Yes
No (Yes in high-accuracy applications)
Yes
 
 
 
 
​Performance
 
 
 
Resolution
High
15º – 1.6º
2º – 0.1º
Lock/free after power-down
Always free
Free, or locking with a permanent magnet. A motor may be always locking OR always free
Yes, the same motor may be controlled just before power-down to lock or be free after power-down
Lock duration
—
Permanent
​Tested to hold for over 3 months with 1020 soft magnetic steel rotor and stator. Need further tests.
​Power consumption
High
Medium (High with micro-steps)
​Low (need power during skips only)
Can directly produce linear motion
No (not counting linear motors that are different designs)
No
Yes, with 5μm-1μm resolution and no backlash
Life limited by ball bearings 
Yes (much shorter life with brushes)
Yes 
No 
 
 
 
 
Accuracy
 
 
 
Positioning resolution
High
Low
High
Positioning repeatability 
Sensor dependent
High
Sensor dependent 
 
 
 
 
Other
 
 
 
Noise
Low
Low
Medium at high frequency, can be shielded