Exercise system

A control means for controlling the electrical output of a DC generator means forming part of an exercise device, comprising:

• a) user actuatable mechanism for imparting rotation to said DC generator means;
• b) power dissipation means for dissipating power generated by said DC generator means upon actuation by said actuating mechanism;
• c) reference signal input means for inputing a reference signal to said control means;
• and
• d) comparing means forming part of said control means for comparing power output of said exercise device including means for adjusting said power dissipation means if an error exists between said reference signal and a signal derived from the voltage and current output of said generator means;
• and,
• f) heat sink means forming part of said exercise device operative to dissipate heat generated by said power dissipation means.

An exercise system, comprising:

• a) an exercise device including:
• i) a user operated device actuating mechanism;
• ii) a DC generator means coupled to the actuating mechanism such that actuation of the mechanism by the user produces rotation in a drive shaft of said DC generating means;
• b) electronic control means for controlling a braking effect exerted by said DC generator means on said actuating mechanism;
• c) DC power supply means for electrically powering said electronic control means, comprising:
• i) means connecting an output of said DC generator means to a first stage voltage regulation means;
• ii) said first stage regulation means operative to limit voltage applied to a second stage voltage regulation means to a predetermined maximum voltage;
• iii) said second stage voltage regulation means including separate positive and negative voltage regulators operative to provide relatively low positive and negative power supply voltages for said electronic control means.

A method of controlling a loading device in an exercise system, comprising the steps of:

• a) coupling a DC generator means to a user actuatable mechanism such that actuation of said mechanism produces rotation in said DC generator means;
• b) controlling a braking effect exerted by said DC generator means on said actuating mechanism by:
• i) substantially continuously comparing a power output signal derived from the voltage and current output of said generator means with a reference signal;
• and,
• ii) adjusting the conductivity of at least one power MOSFET forming part of a power dissipation means in response to sensed differences between said reference signal and said power output signal.

An exercise device comprising:

• a) a user operated device actuating mechanism;
• b) a DC generator means mechanically coupled to said actuating mechanism by a coupling means such that actuation of said actuating mechanism produces rotation in a drive shaft of said DC generating means;
• c) power dissipation means operative to dissipate the electrical output of said DC generator means in order to control a braking effect exerted by said DC generator means on said actuating mechanism;
• and,
• d) multiplying means including:
• i) a voltage to frequency converter operative to convert a voltage signal related to the current output of said DC generator means to a signal comprising a series of pulses in which the frequency of said signal pulses is proportional to an output current of said generator means;
• ii) amplitude adjusting means for adjusting the amplitude of said signal pulses such that the amplitude of said signal pulses is proportional to the output voltage of said DC generator means;
• and
• iii) integrating means for integrating said frequency and an amplitude varying signal to produce an integrated signal that is proportional to the electrical power output of said generating means.

A method of controlling a loading device in an exercise system, comprising the steps of:

• a) coupling a DC generator means to a user actuatable mechanism such that actuation of said mechanism produces rotation in said DC generator means;
• b) determining the power output of the exercise system by:
• c) producing a first power signal proportional to the product of the output current and voltage of the generator means using a multiplying means;
• d) deriving a total power signal by summing said first power signal with a compensation signal that is proportional to internal electrical losses in said generator means;
• e) controlling a braking effect exerted by said DC generator means on said actuating mechanism by:
• i) substantially continuously comparing said total power signal with a reference signal;
• and,
• ii) adjusting the dissipation rate of a power dissipation means in response to sensed differences between said reference signal and said total power signal.

A method of controlling a loading device in an exercise system, comprising the steps of:

• a) coupling a DC generator means to a user actuatable mechanism such that actuation of said mechanism produces rotation in said DC generator means;
• b) determining the power output of the exercise system by:
• c) producing a first power signal proportional to the product of the output current and voltage of the generator means using a multiplying means;
• d) deriving a total power signal by summing said first power signal with a compensation signal that is proportional to internal electrical losses in said generator means and the mechanical loads imposed by said user actuated mechanism;
• e) controlling a braking effect exerted by said DC generator means on said actuating mechanism by:
• i) substantially continuously comparing said total power signal with a reference signal;
• and,
• ii) adjusting the dissipation rate of a power dissipation means in response to sensed differences between said reference signal and said total power signal.