초록 ▼

The specification discloses an exercise treadmill for diagnostic and therapeutic purposes incorporating an improved drive and control system. High efficiency at low rpm is effectuated through the use of a DC motor which maintains the belt speed constant by varying the width of the applied pulse dura

The specification discloses an exercise treadmill for diagnostic and therapeutic purposes incorporating an improved drive and control system. High efficiency at low rpm is effectuated through the use of a DC motor which maintains the belt speed constant by varying the width of the applied pulse duration as a function of load. Additional load buffering between the belt and motor is effectuated by a double flywheel configuration.

대표청구항 ▼

A treadmill for diagnostic and therapeutic purposes comprising: an endless belt supported at each end by a cylindrical roller; a DC motor; a DC reference voltage; velocity sensing means responsively coupled to said DC motor for generating a voltage which is proportional to the angular speed of said

A treadmill for diagnostic and therapeutic purposes comprising: an endless belt supported at each end by a cylindrical roller; a DC motor; a DC reference voltage; velocity sensing means responsively coupled to said DC motor for generating a voltage which is proportional to the angular speed of said DC motor; pulse width control means responsively connected to said velocity sensing means for generating a gating pulse having a duration which is proportional to the difference between the voltage generated by said velocity sensing means and said reference voltage; means for coupling said DC motor to said endless belt; power supply means for converting a standard 110 volt 60 cps household power to a unidirectional potential; switching means having its main terminals series connected between said DC motor and the output of said power supply means and its gating terminal responsively connected to said pulse width control means, for controlling the duration of the DC voltage applied to said DC motor in response to the width of the pulses generated by said pulse width control means at least one semiconductor switching device; a choke means having a low DC resistance; a resistor connected in parallel with said choke means; means for connecting said switching device in series with the parallel combination of said resistor and said choke means, and; means for connecting the network comprised of said semiconductor switching device and said choke means and said resistor in parallel with said DC motor, and; means for actuating said switching device so as to cause said switching device to short circuit said choke means and resistor network across the terminals of said DC motor.