North American Philips Corporation

Brunswick Corporation

Motorola Corporation

Philips Electronics North America Corporation

Advance Transformer Company

John M Wong

Mark W Fellows

Edmond Toy

Ming Jiang

Ferdinand David

Robert Sutkowski

Robert A Erhardt

Michael A Kurczak

James A Thomsen, Jr

Dennis L Stephens

Hubie Notohamiprodjo

Methods and apparatus to power an exercise machine are disclosed herein. An example exercise machine includes a power receiver to measure a power output by a generator that is to convert movement of a moveable part into electric power, the power receiver is to calculate a rotations per minute of the moveable part. A mode controller is to calculate a power supply duty cycle based on the power output by the generator, the rotations per minute of the moveable part, and a user selected wattage. A power output controller is to control power provided to a console of the exercise machine based on the power supply duty cycle.

Methods and apparatus to power an exercise machine

Methods and apparatus to power an exercise machine are disclosed herein. An example exercise machine includes a generator to convert movement of a moveable part of the exercise machine into electric power. The example exercise machine includes a generator power receiver to measure the power output by the generator, and to calculate a rotations per minute of the moveable part. A mode controller is to calculate a power supply duty cycle based on the power output by the generator, the rotations per minute of the moveable part, and a user selected wattage. A power output controller is to control power provided to a console of the exercise machine based on the power supply duty cycle.

Methods and apparatus to power an exercise machine are disclosed herein. An example method includes measuring a power supply current produced by a user of the exercise machine. A rotations per minute of the exercise machine is measured. A power supply reference current is determined, the power supply reference current based on a user selected wattage and the rotations per minute. A differential power supply current is calculated based on the power supply reference current and a measured current of a power supply of the exercise machine. A power supply duty cycle is calculated based on a previous power supply duty cycle, a time constant, the differential power supply current, and a previous differential power supply current, the power supply duty cycle to control power supplied to a console of the exercise machine. The power supply duty cycle is output to a power output controller.

A ballast circuit uses an optocoupler to provide electrical isolation of the dimming control from the remainder of the ballast. The optocoupler is operated in the linear range to provide continuous dimming of the lamps. The circuit further uses a combination of diodes and a diode bridge to steer current from the current sensor during lamp out conditions so that the inverter will maintain operation at a low frequency, thereby maximizing the output voltage. A clamp winding is used to insure that the voltage does not exceed the DC rail voltage.

Dimming circuit for powering gas discharge lamps

A fluorescent lamp ballast having improved power factor by providing high frequency signals fed back to the a.c. side of the ballast rectifier. The feedback signal is regulated by limiting or reducing the voltage gain of the feedback signal based on the level of the unregulated feedback signal or rectified signal, respectively.

Fluorescent lamp ballast with regulated feedback signal for improved

A compact fluorescent lamp in combination with a high frequency DC-AC converter includes a rectifier circuit and a buffer capacitor coupled between a source of low frequency AC voltage and the converter. A feedback capacitor couples a high frequency feedback signal corresponding to the converter output signal to the buffer capacitor via the rectifier circuit so as to improve the power factor of the combination.

Compact fluorescent lamp with improved power factor

An electronic controller for fluorescent lamps includes a DC to AC converter which supplies high frequency current to the lamps and a preconditioner stage which includes a switched mode power supply connected to accept line power and produce a DC input for the DC to AC converter. The switched mode power supply and the DC to AC converter are synchronized to operate in a fixed phase relationship and/or at the same frequency.

Fluorescent lamp controllers

A controller operates in pre-ignition and ignition phases to obtain stable and reliable control of operation of a half-bridge DC-AC converter in a frequency range which is offset from a resonant frequency of an output circuit which includes a transformer and capacitors and which couples the converter to a fluorescent lamp load. The converter is supplied with a DC voltage from a switched-mode DC-DC supply of a pre-conditioner circuit which responds to a full-wave rectified AC voltage and which is supplied with pulse-width modulated gating pulses from the controller, preferably at a frequency which is the same as that of the converter. The controller monitors signals from the output circuit and pre-conditioner circuits and exercises control to reliable starting and highly efficient lamp operation and to obtain an in-phase proportional relationship of input voltage and current wave forms.

This invention relates to fluorescent lamp controllers and dimming controls for use therewith and more particularly to the provision of a dimming control which provides protective isolation between input terminals and lamp energizing circuitry and which facilitates accurate and safe control of light intensity over a wide range. The invention provides dimming controls which are efficient and highly reliable and are readily and economically available.

Fluorescent lamp controllers with dimming control

A fluorescent lamp controller uses a dimmer circuit having an isolation transformer. The controller applies a high frequency current to the primary winding of the transformer. The secondary winding is coupled to a control input via loading circuitry. A detector circuit supplies a signal to the lamp controller indicative of the resultant loading of the transformer to control lamp intensity.

A controller operates in pre-ignition and ignition phases to obtain stable and reliable control of operation of a half-bridge DC-AC converter in a frequency range which is offset from a resonant frequency of an output circuit which includes a transformer and capacitors and which couples the converter to a fluorescent lamp load. The converter is supplied with a DC voltage from a switched-mode DC-DC supply of a pre-conditioner circuit which responds to a full-wave rectified AC voltage and which is supplied with pulse-width modulated gating pulses from the controller, preferably at a frequency which is the same as that of the converter. The controller monitors signals from the output circuit and pre-conditioner circuits and exercises control to reliable starting and highly efficient lamp operation and to obtain an in-phase proportional relationship of input voltage and current waveforms.

A power supplier for providing a regulated high-frequency AC output with a bucking and boosting section and a push-pull output section in which a common switching element is used in both the bucking and boosting section and in the push-pull output section.

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Buffalo Grove, IL, United States of America

John M Wong