Vibration generating apparatus

Patent metadata

Field	Value
Publication number	US-9263983-B2
Application number	US-201414547829-A
Country	US
Kind code	B2
Filing date	Nov 19, 2014
Priority date	Jul 27, 2010
Publication date	Feb 16, 2016
Grant date	Feb 16, 2016

Abstract

A vibration generating apparatus with high yield, low cost, and can exhibit vibration tactile haptic effects even with variation in the natural frequency of a mechanical vibrator, including a damping system having a damping ratio ζ<1 to support a mechanical vibrator to a fastening part, and a magnetizing unit generating a dynamic magnetic field to vibrate the mechanical vibrator by non-contact, the mechanical vibrator generating a beat vibration by making the frequency of a drive voltage applied to the magnetizing unit, from a drive start or middle of drive, to be a non-resonant frequency out of a damped natural frequency of the mechanical vibrator, wherein the apparatus comprises a forced vibration control unit controlling to stop application of the drive voltage, in a beat wave defining an amplitude of the beat vibration, at a second valley part after a first peak part from the side of the drive start.

First claim

The invention claimed is:

1. A vibration generating apparatus including a damping system having a damping ratio ζ<1 to support a mechanical vibrator with respect to a fastening part through a spring element, and a magnetizing means generating a dynamic magnetic field to vibrate said mechanical vibrator without contact, said mechanical vibrator generating a beat vibration by making the frequency of a drive voltage applied to said magnetizing means, from a drive start or middle of drive, to be a non-resonant frequency out of a damped natural frequency of said mechanical vibrator, wherein:
said vibration generating apparatus comprises a forced vibration control means controlling to stop application of said drive voltage, in a beat wave defining an amplitude of said beat vibration, at a second valley part after a first peak part from the side of said drive start, and
a frequency of said drive voltage is substantially ⅓ of said damped natural frequency and wherein said drive voltage applied to said magnetizing means is a sine half wave.

2. The vibration generating apparatus as set forth in claim 1 , wherein said forced vibration control means suppresses an amplitude of said drive voltage at said second valley part before stopping application of said drive voltage.

3. The vibration generating apparatus as set forth in claim 1 , wherein said forced vibration control means suppresses an amplitude of said drive voltage of a period falling from said first peak part to said second valley part more than an amplitude of said drive voltage of a period rising from said first valley part to said first peak part.

4. The vibration generating apparatus as set forth in claim 1 , wherein said drive voltage applied to said magnetizing means has a repeating waveform of a unipolar voltage.

5. The vibration generating apparatus as set forth in claim 1 , wherein said forced vibration control means sets the frequency of said drive voltage so that a beat period of a beat wave of said beat vibration and a period of a basic wave of said beat vibration become substantially equal.

6. The vibration generating apparatus as set forth in claim 1 , wherein said forced vibration control means outputs a frequency of said drive voltage across a certain period from said drive start as a resonant frequency matched with said damped natural frequency, then switches to said non-resonant frequency.

7. The vibration generating apparatus as set forth in claim 1 , wherein the number of cycles of the damped natural frequency is smaller than the number of cycles of said non-resonant frequency.

8. The vibration generating apparatus as set forth in claim 1 , wherein said mechanical vibrator has a ring-shaped permanent magnet which is magnetized in a thickness direction spanning a first end face and a second end face, said spring element is a suspension spring means supporting said ring-shaped permanent magnet displaceably in said thickness direction with respect to said fastening part, said electromagnetic coil passes through a center hole of said ring-shaped permanent magnet and is supported at said fastening part, a core is provided passing through the inside of said electromagnetic coil, said electromagnetic coil has a first toroidal coil and an adjoining coaxial second toroidal coil with opposite magnetization polarities, and provision is made of a first ring-shaped pole piece mated with said first end face and having an inner circumferential edge surrounding an outer circumference surface of said first toroidal coil and a second ring-shaped pole piece mated with said second end face and having an inner circumferential edge surrounding an outer circumference surface of said second toroidal coil.

Assignees

• Nidec Seimitsu Corp

Inventors

• Miyazaki Masahiko

Classifications

• H02K33/16

  with polarised armatures moving in alternate directions by reversal or energisation of a single coil system · CPC title

• H02K33/00 Primary

  Motors with reciprocating, oscillating or vibrating magnet, armature or coil system (arrangements for handling mechanical energy structurally associated with motors H02K7/00, e.g. H02K7/06) · CPC title

• B06B1/0207 Primary

  Driving circuits (specially adapted for particular applications, see the relevant subclass, e.g. G01; circuits for steering transducer arrays G10K11/34; basic circuits H03) · CPC title

• B06B2201/30

  with electronic damping · CPC title

• B06B2201/70

  Specific application · CPC title