Patent 10183119 was granted and assigned to Novo Nordisk on January, 2019 by the United States Patent and Trademark Office.
An add-on dose logging device for a pen device consumes energy when the sensors are operated and when the display is active. By using cap-off event to activate the sensor system only, and using cap-on event to de-activate the sensor system and activate the display for a given time to display a sensed dose, power consumption can be reduced without changing the user-interface and without adding any components apart from a switch.