Sudden stop circuit for a brushless micromotor

• US 4,587,468 A
• Filed: 01/18/1985
• Issued: 05/06/1986
• Est. Priority Date: 01/25/1984
• Status: Expired due to Fees

• Current Assignee: Kabushiki Kaisha Morita Seisakusho
• Original Assignee: Kabushiki Kaisha Morita Seisakusho
• Inventors: Hotta, Toshihiro
• Primary Examiner(s): Shoop, Jr., William M.
• Assistant Examiner(s): Ro, Bentsu
• Application Number:
  US06/692,832
• Time in Patent Office: 473 Days
• Field of Search: 318/138, 318/254 A, 318/254, 318/362, 318/439
• US Class Current: 318/362
• CPC Class Codes: H02P 6/24 Arrangements for stopping

Abstract

A sudden stop circuit for a brushless micromotor comprising a means for detecting the off state of the on/off switch of the brushless micromotor and a means for applying a locking pulse signal to at least one motor coil for a specified period depending on the off state detection signal generated by the detection means, whereby the motor rotor is braked by the electromagnetic force generated in the motor coil by the locking pulse signal. This circuit is compact and can apply great braking force to stop the motor in an extremely short time.

Claims

1. A sudden stop circuit for a brushless micromotor comprising a means for detecting the off state of an on/off switch of said brushless micromotor and a means for applying a locking pulse signal to at least one motor coil for a specified period depending on the off state detection signal generated by said detection means, said means for applying a locking pulse signal comprising a capacitor which is discharged when the off state of said on/off switch is detected by said detection means and said locking pulse signal having a voltage level corresponding to the discharge voltage of said capacitor is generated and applied to at least one motor coil via a brushless motor drive circuit by said means for applying a locking pulse signal, whereby said motor rotor is braked by the electromagnetic force generated in said motor coil by said locking pulse signal.