Occlusion detection using pulse-width modulation and medical device incorporating same
AssigneeMedtronic MiniMed, Inc.
InventorJacques L. Favreau
Life of this patent
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Abstract
Apparatus are provided for motor control systems and related medical devices. In one embodiment, a control system includes a motor having a rotor, a modulation module coupled to the motor, and a control module coupled to the modulation module. The modulation module generates a modulated voltage that is applied to the motor and rotates the rotor to deliver fluid via a fluid path. The control module adjusts a duty cycle of the modulated voltage to achieve a commanded rotation of the rotor and detects an occlusion condition in the fluid path based on the duty cycle.
Claims25
An infusion device, comprising:
- a motor having a rotor;
- a stopper mechanically coupled to the rotor, the stopper being displaced to deliver fluid via a fluid path in response to rotation of the rotor;
- a modulation module coupled to the motor, the modulation module generating a modulated voltage applied to the motor, the modulated voltage oscillating between a first voltage and a second voltage, the modulated voltage being equal to the first voltage for a percentage of a time interval, the percentage corresponding to a duty cycle;
- and
- a control module coupled to the modulation module to adjust the duty cycle to achieve a commanded rotation of the rotor and detect an occlusion condition in the fluid path based on the duty cycle.
An infusion device, comprising:
- a stepper motor having a rotor;
- a stopper mechanically coupled to the rotor, the stopper being displaced to deliver fluid via a fluid path in response to rotation of the rotor;
- a modulation module coupled to the stepper motor, the modulation module generating a modulated voltage applied to the stepper motor, the modulated voltage oscillating between a supply voltage and a reference voltage, the modulated voltage being equal to the supply voltage for a percentage of a time interval, the percentage corresponding to a duty cycle;
- and
- a control module coupled to the modulation module to adjust the duty cycle to achieve a commanded rotation of the rotor and detect an occlusion condition in the fluid path based on the duty cycle.
A system for detecting occlusion in a fluid path, the system comprising:
- a motor having a rotor, rotation of the rotor resulting in delivery of fluid via the fluid path;
- a modulation module coupled to the motor, the modulation module generating a modulated voltage applied to the motor, the modulated voltage oscillating between a first voltage and a second voltage, the modulated voltage being equal to the first voltage for a percentage of a time interval, the percentage corresponding to a duty cycle;
- and
- a control module coupled to the modulation module to adjust the duty cycle to achieve a commanded rotation of the rotor and detect an occlusion condition in the fluid path based on the duty cycle.
Dependencies are inferred from the claim text.