Classifications

• • A—HUMAN NECESSITIES
  • A62—LIFE-SAVING; FIRE-FIGHTING
  • A62B—DEVICES, APPARATUS OR METHODS FOR LIFE-SAVING
  • A62B18/00—Breathing masks or helmets, e.g. affording protection against chemical agents or for use at high altitudes or incorporating a pump or compressor for reducing the inhalation effort
  • A62B18/02—Masks
• • A—HUMAN NECESSITIES
  • A62—LIFE-SAVING; FIRE-FIGHTING
  • A62B—DEVICES, APPARATUS OR METHODS FOR LIFE-SAVING
  • A62B18/00—Breathing masks or helmets, e.g. affording protection against chemical agents or for use at high altitudes or incorporating a pump or compressor for reducing the inhalation effort
  • A62B18/006—Breathing masks or helmets, e.g. affording protection against chemical agents or for use at high altitudes or incorporating a pump or compressor for reducing the inhalation effort with pumps for forced ventilation
• • A—HUMAN NECESSITIES
  • A62—LIFE-SAVING; FIRE-FIGHTING
  • A62B—DEVICES, APPARATUS OR METHODS FOR LIFE-SAVING
  • A62B18/00—Breathing masks or helmets, e.g. affording protection against chemical agents or for use at high altitudes or incorporating a pump or compressor for reducing the inhalation effort
  • A62B18/02—Masks
  • A62B18/025—Halfmasks
• • A—HUMAN NECESSITIES
  • A62—LIFE-SAVING; FIRE-FIGHTING
  • A62B—DEVICES, APPARATUS OR METHODS FOR LIFE-SAVING
  • A62B18/00—Breathing masks or helmets, e.g. affording protection against chemical agents or for use at high altitudes or incorporating a pump or compressor for reducing the inhalation effort
  • A62B18/08—Component parts for gas-masks or gas-helmets, e.g. windows, straps, speech transmitters, signal-devices
• • A—HUMAN NECESSITIES
  • A62—LIFE-SAVING; FIRE-FIGHTING
  • A62B—DEVICES, APPARATUS OR METHODS FOR LIFE-SAVING
  • A62B23/00—Filters for breathing-protection purposes
  • A62B23/02—Filters for breathing-protection purposes for respirators
  • A62B23/025—Filters for breathing-protection purposes for respirators the filter having substantially the shape of a mask
• • A—HUMAN NECESSITIES
  • A62—LIFE-SAVING; FIRE-FIGHTING
  • A62B—DEVICES, APPARATUS OR METHODS FOR LIFE-SAVING
  • A62B9/00—Component parts for respiratory or breathing apparatus
  • A62B9/02—Valves
  • A62B9/022—Breathing demand regulators

Definitions

• the benefit to the wearer of using a powered mask is that the lungs are relieved of the slight strain caused by inhalation against the resistance of the filters in a conventional non-powered mask.
• a controller which is adapted to:
• the fan is for providing an increased pressure in the air chamber (e.g. a flow into the air chamber during inhalation), it is only required to provide a small increased pressure, for example for assisting inhalation of the user.
• This heat index value is representative of the general ambient environmental conditions and can be used so that the fan speed is set taking into account the expected user comfort in those particular conditions.
• An internal sensor is already provided in such motors to enable rotation of the motor.
• the motor may even have an output port on which the internal sensor output is provided.
• a ripple is detected which results from switching current through the motor coils, which cause induced changes in the supply voltage as a result of the finite impedance of the input voltage source.
• Figure 5 shows a circuit for controlling the current through one of the stators of a brushless DC motor
• outlet valve 22 When the subject breathes out, air is exhausted through the outlet valve 22.
• This valve is opened to enable easy exhalation, but is closed during inhalation.
• a fan 20 assists in the removal of air through the outlet valve 22. Preferably more air is removed than exhaled so that additional air is supplied to the face. This increases comfort due to lowering relative humidity and cooling.
• the outlet valve may be a simple passive check valve operated by the pressure difference across the filter 16. However, it may instead be an electronically controlled valve.
• the pressure variation may be used to obtain information about the breathing of the user.
• a first value may represent the depth of breathing and a second value may represent the rate of breathing.
• the first and second values are used to set the fan speed. Furthermore, by detecting an equal pressure on each side the fan (or other conditions relating to the first and second values), it can also be determined that the chamber is not closed but is connected to atmospheric pressure on both sides.
• the means for determining the rotation speed may comprise a circuit 36 for detecting a ripple on the electrical supply to the motor 20b.
• the ripple results from switching current through the motor coils, which cause induced changes in the supply voltage as a result of the finite impedance on the battery 32.
• the circuit 36 for example comprises a high pass filter so that only the signals in the frequency band of the fan rotation are processed. This provides an extremely simple additional circuit, and of much lower cost than a conventional pressure sensor.
• Figure 4A shows schematically the rotor position (as a measured sensor voltage) against time.
• Figure 4B shows the frequency variation over time, by plotting the fan rotation speed versus time. There is a maximum difference in fan rotation speed Afan between successive maxima and minima, and this correlates with the depth of breathing. This is the first value derived from the fan rotation signal. The time between these points is used to derive the second value, for example the frequency corresponding to this time period (which is then twice the breathing rate).
• FIG. 5 shows an H-bridge circuit which functions as an inverter to generate an alternating voltage to the stator coils 50 of the motor from a DC supply VDD, GND.
• the inverter has a set of switches SI to S4 to generate an alternating voltage across the coil 50.
• the switches are controlled by signals which depend on the rotor position, and these rotor position signals may be used to monitor the fan rotation.
• the first value representing the depth of breathing, may be based on the maximum swing in rotation speed captured within a sampling window (of at least one breath, for example 5 seconds) as shown in Figure 4B:
• the invention may again be applied for detecting the pressure variations caused by breathing for controlling the inlet valve and/or the outlet valve.
• the fan in this example needs to be turned on during inhalation, to assist the user in drawing air through the series filter, but it may be turned off during exhalation when the outlet valve is open.
• the pressure information derived may again be used to control the fan to save power when the fan operation is not needed.
• the detection of whether the mask is worn or not may also be implemented.
• a second value is derived which relates to a rate of breathing based on the time between a consecutive maxima and minima in the fan rotation speed.
• Other analysis of the fan rotation speed may be used.
• the time may be between consecutive maxima (so not using the timing of the minima), or between
• the fan speed is controlled with multiple possible fan speed values.
• the fan speed is not only controlled between an on fan speed and a zero (off) fan speed.
• the example above has 5 fan speed settings, but there may be more than 5.
• step 72 determining a rotation speed of the fan
• a processor or controller may be associated with one or more storage media such as volatile and non-volatile computer memory such as RAM, PROM, EPROM, and EEPROM.
• the storage media may be encoded with one or more programs that, when executed on one or more processors and/or controllers, perform the required functions.
• Various storage media may be fixed within a processor or controller or may be transportable, such that the one or more programs stored thereon can be loaded into a processor or controller.

Landscapes

• Health & Medical Sciences (AREA)
• Pulmonology (AREA)
• General Health & Medical Sciences (AREA)
• Business, Economics & Management (AREA)
• Emergency Management (AREA)
• Life Sciences & Earth Sciences (AREA)
• Zoology (AREA)
• Respiratory Apparatuses And Protective Means (AREA)

Applications Claiming Priority (3)

Publications (1)

Family

ID=68501623

Family Applications (1)

Country Status (4)

Families Citing this family (20)

Citations (1)

Family Cites Families (15)

• 2019
  • 2019-11-08 CN CN201911088591.1A patent/CN111167039B/zh not_active Expired - Fee Related
  • 2019-11-08 CN CN201921922759.XU patent/CN212214401U/zh not_active Withdrawn - After Issue
  • 2019-11-08 JP JP2021523164A patent/JP7402870B2/ja active Active
  • 2019-11-08 EP EP19801016.7A patent/EP3877057A1/en not_active Withdrawn
  • 2019-11-08 WO PCT/EP2019/080709 patent/WO2020094850A1/en not_active Ceased
  • 2019-11-08 CN CN201980073329.1A patent/CN113038993A/zh active Pending

Patent Citations (2)

Non-Patent Citations (1)

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