3m Innovative Properties Company

Bengt Kallman

Andrew Murphy

Desmond T Curran

Christopher P Henderson

Garry J Walker

Bengt Garbergs

Alan W Lee

Christopher N Findlay

Hans-Olof Frojd

Terence M Sayers

Vladimir Dubrovskii

Hans-Olof FRÖJD

A powered air purifying respirator (PAPR) for delivering a forced flow of filtered air to a wearer is disclosed. The PAPR comprises a turbo unit with turbo unit components including a fan, an electric motor, and an electronic control unit having a wireless electronic control transceiver, the fan being driven by the electric motor under the control of the electronic control unit and the electronic control unit being configured to send and receive information via the electronic control transceiver; a turbo unit power source that provides power to the turbo unit components; a turbo remote control unit having a wireless turbo remote control transceiver; at least one turbo status indicator unit, adapted to indicate a current operating status of the turbo unit and/or turbo unit components, having a wireless turbo status transceiver; wherein at least one of the turbo remote control unit and turbo status indicator unit is remote from the turbo unit, and wherein at least two of the electronic control transceiver, the turbo remote control transceiver and the turbo status transceiver are in wireless communication with each other.

Powered air-purifying respirator

Powered air purifying respirator unit control panel

A method of controlling a powered air purifying respirator blower system to deliver a substantially uniform volumetric airflow to a user includes the steps of determining one of (a) ambient air density or (b) ambient air temperature and ambient air pressure, and adjusting an electrical characteristic of the electric motor in response to the determination and the at least two calibration values. The powered air purifying respirator blower system may include a fan powered by an electric motor, the motor being controlled by an electronic control unit for delivering a forced flow of filtered air to a user. In some embodiments, the electronic control unit may be operable to adjust an electrical characteristic of the motor in accordance with a predetermined correlation between the speed of the fan and the applied motor electrical characteristic for a selected substantially uniform volumetric airflow from the fan.

Method of controlling a powered air purifying respirator

A method and configuration from maintaining a constant of air to a protective helmet () from a fan () in a battery powered fresh air unit. The fan () is a radial fan with a filter () positioned on the suction side of the fan and is operated by a brushless continuous current motor (). With the aid of signals from position sensors () in the motor (), a control unit () can determine the speed of the fan (). The control unit also detects the motor's power consumption and compares this and the speed with a characteristic curve for the motor () for a given flow from the fan, which is stored in a memory (). In the event of any deviation, the control unit () regulates a change of the voltage supply to the motor () so that the deviation is reduced.

Process and device for flow control of an electrical motor fan

Growing community of inventors

Leksand, Sweden

Bengt Kallman