Sound activated liquid display device
US6746131B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 11, 2002 |
| Grant date | Jun 8, 2004 |
| Priority date | — |
| Expiry date | Feb 11, 2022 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02B20/40
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A transparent container has two immiscible liquids of different densities, colors and viscosities. A pump with a magnetic coupling injects the denser liquid upwardly into the less dense liquid in response to changes in sound volume or frequency of the vicinity of the device providing a geyser display reactive to music or voice. Pump control circuitry includes a microphone, an amplifier; a filter for extracting a beat from dance music or syllabic content of speech; an amplitude detector for detecting a short-time amplitude envelope; a long time averager providing a reference signal proportional to the average sound level and an attenuator; a comparator connected to both the averager and the attenuator to change state when the attenuated version of the short time amplitude envelope momentarily rises above reference signal to provide an activating signal to a pump power controller causing electric power to be delivered to the pump.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.