Method and system of calibrating air flow in a respirator system

• US 6,666,209 B2
• Filed: 02/20/2001
• Issued: 12/23/2003
• Est. Priority Date: 02/20/2001
• Status: Expired due to Term

• Current Assignee: 3M Innovative Properties Company (3M Company)
• Original Assignee: 3M Innovative Properties Company (3M Company)
• Inventors: Bennett, Michael R., Cook, David
• Primary Examiner(s): Lewis, Aaron J.
• Application Number:
  US09/788,786
• Publication Number:
  US 20030019494A1
• Time in Patent Office: 1,036 Days
• Field of Search: 128/200.24, 128/202.22, 128/204.18, 128/204.21, 128/204.23, 128/204.26
• US Class Current: 128/200.24
• CPC Class Codes: A62B 18/006 with pumps for forced ventilation A62B18/045 takes precedence

Abstract

A method and apparatus for calibrating the air flow in a respirator system is provided. The method provides for the establishment of control set points in a true calibration protocol through the simple triggering of the microprocessor of a controller. When the trigger is initiated, the microprocessor engages and provides the logic for the calibration cycle. The calibration cycle proceeds until a second trigger terminates the process and establishes the control set points. The calibration sequence of the method relies only on an initiation and termination trigger that is facilitated by components integral to the apparatus.

Claims

1. A method of calibrating the air flow in a respirator system having a blower with a motor and a controller having a microprocessor, the method comprising:

providing a first triggering signal to the microprocessor to begin a calibration cycle;

using the first triggering signal to set the motor to a first speed by the controller;

varying the motor speed by the controller;

providing a second triggering signal to the microprocessor to end the calibration cycle and to establish a control set point; and

monitoring air flow from the blower while varying the motor speed.

2. The method of claim 1, wherein the respirator system comprises a powered air-purifying respirator.

3. The method of claim 1, wherein establishing a control set point comprises measuring and storing at least one of a set of measured parameters related to control of the motor.

4. The method of claim 3, wherein the measured parameters include at least one of the current through the motor, the voltage across the motor, the speed of the motor, and air flow.

5. The method of claim 1, wherein the first and second triggering signals are provided by a mechanical switch.

6. The method of claim 1, wherein the first and second triggering signals are provided by an electronic gate.

7. The method of claim 1, wherein the flow rate monitoring is performed with a flow meter.

8. The method of claim 1, wherein the step of varying the motor speed includes acceleration of the motor speed.

9. The method of claim 1, wherein the step of varying the motor speed includes decelerating the motor speed.

10. The method of claim 1, wherein the step of varying the motor speed includes varying the motor speed at a constant rate.

11. A method for capturing a control set point in the calibration of a feedback control system of a respiratory system, the method comprising the steps of:

providing a respirator system having a blower with a motor and a controller having a microprocessor;

triggering the microprocessor to begin a calibration cycle;

establishing a first motor speed by the controller;

accelerating the motor speed by the controller;

triggering the microprocessor to capture the control set point and end the calibration cycle; and

monitoring air flow from the blower while accelerating the motor speed.

12. A respirator system for supplying air to a user, the respirator system comprising a blower with a motor and a controller having a microprocessor, wherein the flow of air to the user is calibrated by providing a first triggering signal to the microprocessor to begin a calibration cycle, using the first triggering signal to set the motor to a first speed by the controller, varying the motor speed by the controller, providing a second triggering signal to the microprocessor to end the calibration cycle and to establish a control set point, and monitoring air flow from the blower while varying the motor speed.

13. A method of calibrating air flow in a powered air purifying respirator system, the method comprising:

initiating a calibration cycle by providing a first triggering signal to a microprocessor in a controller of a blower motor driving a blower in the powered air purifying respirator system;

changing speed of the blower motor using the controller after initialing the calibration cycle;

monitoring air flow in the powered air purifying system while changing the speed of the blower motor;

terminating the calibration cycle by providing a second triggering signal to the microprocessor; and

monitoring and storing at least one motor parameter for the blower motor to establish a control set point.

14. A method according to claim 13, further comprising providing the second triggering signal when the air flow in the powered air purifying system reaches a desired flow rate.

15. A method according to claim 13, wherein monitoring air flow in the powered air purifying system comprises monitoring the air flow using a flow measuring instrument, and further wherein the second triggering signal is provided to the microprocessor by a human operator monitoring the flow measuring instrument.

16. A method according to claim 13, wherein monitoring air flow in the powered air purifying system comprises monitoring the air flow using a flow measuring instrument, and further wherein the second triggering signal is provided to the microprocessor by the flow measuring instrument when the air flow from the blower reaches a desired flow rate.

17. A method according to claim 13, wherein storing at least one motor parameter for the blower motor to establish a control set point occurs alter providing the second triggering signal to the microprocessor.

18. A method according to claim 13, wherein changing speed of the blower motor using the controller comprises increasing the speed of the blower motor from a base line speed.

19. A method according to claim 13, wherein changing speed of the blower motor using the controller comprises decreasing the speed of the blower motor from a base line speed.

20. A powered air purifying respirator system for supplying air to a user, the system comprising a blower, a blower motor driving the blower, and a controller comprising a microprocessor controlling the blower motor, wherein air flow to the user is calibrated by initiating a calibration cycle by providing a first triggering signal to the microprocessor;

changing speed of the blower motor using the controller after initiating the calibration cycle;

monitoring air flow in the powered air purifying system while changing the speed of the blower motor;

terminating the calibration cycle by providing a second triggering signal to the microprocessor; and

monitoring and storing at least one motor parameter for the blower motor to establish a control set point.