WO1997037724A1 - A communication interface for breathing equipment - Google Patents

A communication interface for breathing equipment Download PDF

Info

Publication number
WO1997037724A1
WO1997037724A1 PCT/AU1997/000216 AU9700216W WO9737724A1 WO 1997037724 A1 WO1997037724 A1 WO 1997037724A1 AU 9700216 W AU9700216 W AU 9700216W WO 9737724 A1 WO9737724 A1 WO 9737724A1
Authority
WO
WIPO (PCT)
Prior art keywords
breathing equipment
breathing
equipment according
mask
microphone
Prior art date
Application number
PCT/AU1997/000216
Other languages
French (fr)
Inventor
Bengt Yngve Roland Jervmo
Martinus Oliver Klockseth
Goran Bertil Claes Berndtsson
Original Assignee
Safety Equipment Australia Pty. Ltd.
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Safety Equipment Australia Pty. Ltd. filed Critical Safety Equipment Australia Pty. Ltd.
Priority to AU21456/97A priority Critical patent/AU2145697A/en
Publication of WO1997037724A1 publication Critical patent/WO1997037724A1/en

Links

Classifications

    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K11/00—Methods or devices for transmitting, conducting or directing sound in general; Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
    • G10K11/18—Methods or devices for transmitting, conducting or directing sound
    • G10K11/22—Methods or devices for transmitting, conducting or directing sound for conducting sound through hollow pipes, e.g. speaking tubes
    • 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
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
    • B63C—LAUNCHING, HAULING-OUT, OR DRY-DOCKING OF VESSELS; LIFE-SAVING IN WATER; EQUIPMENT FOR DWELLING OR WORKING UNDER WATER; MEANS FOR SALVAGING OR SEARCHING FOR UNDERWATER OBJECTS
    • B63C11/00—Equipment for dwelling or working underwater; Means for searching for underwater objects
    • B63C11/02—Divers' equipment
    • B63C11/26—Communication means, e.g. means for signalling the presence of divers

Definitions

  • This invention concerns all types of breathing protection and diving equipment, ranging from simple passive systems where air is drawn through a filter in a face-mask by the wearer's breathing action, to sophisticated powered systems which supply clean air at a regulated positive pressure. In all cases, because some form of face-mask or hood must be worn, communication by the wearer is severely restricted. Background To address the problems of communication while wearing a breathing protection mask, electrical connectors and microphones have been introduced into the masks. Disclosure of the Invention
  • the invention provides breathing equipment including a face part that in use is adjacent at least the mouth of the wearer, the face part being associated with acoustic coupling to a remotely located microphone.
  • the breathing equipment may be used for breathing protection or diving applications.
  • the microphone may, for example, be contained together with its electrical supply and a transmitter in the wearer's breast pocket, and be connected with the face mask of the breathing protection equipment by means of a flexible sound pipe. These arrangements place the microphone, and all other electrical parts remotely from the mask. Among other things this facilitates regular cleaning of the mask, and may improve the reliability of the system generally.
  • the acoustic coupling may comprise a sound pipe which may be made of simple flexible tubing, such as tubing made from plastics materials.
  • a face mask may act as a pressure box and the upper end of the sound pipe can be positioned within the mask cavity.
  • the sound pipe may enter the cavity through a port fabricated in the mask, or through the air supply valving.
  • the sound pipe may have a flared end to funnel the sound pressure waves caused by speech into the pipe.
  • a membrane may be provided over the upper end of the sound pipe to prevent moisture or other material from entering it.
  • the sound pipe may be sealed into a package which also contains the microphone, to provide good transfer of Ihe sound pressure to the microphone.
  • the seal is preferably pneumatic, but if there were a small hole the system will still function.
  • the pressure transmission medium in the pipe may be gaseous or liquid.
  • the cut off frequency for an acoustic coupling pipe is proportional to its diameter, and the medium in the pipe.
  • a tube of 50mm diameter in air will have a cut off frequency of approximately 3KHz, which is just sufficient for the transfer of intelligible speech.
  • An important advantage of the invention arises from having the speaker and the remote microphone both located in essentially the same pressure chamber.
  • the pressure chamber is split into two compartments which are connected together by the acoustic coupling.
  • the acoustic coupling may provide either an hydraulic or pneumatic link to maintain the two compartments at the same pressure, and this enables a pipe of small diameter to be utilised for the acoustic coupling.
  • the diameter of the pipe may be less than that expected to be required by consideration of the diameter and the medium, because of the equal pressures at either end.
  • two microphones may be connected in a noise cancelling arrangement.
  • the first microphone may pick up the noise pk s the speech signals, and the second microphone may be arranged to pick up only the noise signals.
  • An electronic circuit will subtract the two signals in order to provide a clean speech signal.
  • FIG. 1 which is a schematic illustration of an embodiment of the invention.
  • FIG. 2 which is a circuit diagram showing electrical treatment of the sound signals picked up by the embodiment of Figure 1. Disclosure of the Best Modes of the Invention
  • the breathing protection equipment 1 comprises a face mask 2 with some kind of air supply port 3.
  • a sound pipe 4 comprising clear PVC having a inner diameter of 1.5mm, penetrates the mask and terminates in a flared funnel 5 within the mask cavity 6.
  • a membrane 7 covers the open end of the funnel 5.
  • sound pipe 4 is pneumatically sealed in a cavity 8 together with a microphone 9, by means of an adaptor 10.
  • the sound pressure change inside the sealed breathing mask cavity 6 are pneumatically communicated to the sealed cavity 8 and microphone 9 via the air in the sound pipe 4.
  • a second microphone (not shown) is also associated with the lower end of the sound pipe, however, this microphone only picks up ambient noise and does not receive any of the sound communicated by sound pipe 4.
  • the speech and noise signal 11 from microphone 8 is fed to the non-inverting input of an amplifier 12, and the noise signal 13 picked up by the second microphone is fed to the inverting input of amplifier 12.
  • Amplifier 12 subtracts the noise signal from the speech and noise signal to output a clean speech signal 14.
  • the invention has been described with reference to a particular example, it should be appreciated that it may be embodied in many other forms.
  • the invention is not restricted to breathing protection equipment of the type which involves use of a face mask, and it may be applied to those systems where there is no mask cavity, such as hoods or visors.
  • the flare at the upper end of the sound pipe is adapted to provide a sound pick Lip (or collection) cavity.
  • the flare may be dispensed with, since the mask cavity will act as a sound collector.
  • the invention will operate with sound pipes of diameters with a broad range of inner diameters less than about 50mm. Inner diameters of between 1 and 5mm have been found to operate well.
  • the sound pipe could also be used for air stipply in which case a wider diameter could be used.

Landscapes

  • Engineering & Computer Science (AREA)
  • Health & Medical Sciences (AREA)
  • Mechanical Engineering (AREA)
  • Ocean & Marine Engineering (AREA)
  • Pulmonology (AREA)
  • General Health & Medical Sciences (AREA)
  • Business, Economics & Management (AREA)
  • Emergency Management (AREA)
  • Physics & Mathematics (AREA)
  • Acoustics & Sound (AREA)
  • Multimedia (AREA)
  • Respiratory Apparatuses And Protective Means (AREA)

Abstract

This invention concerns all types of breathing equipment, ranging from simple passive systems where air is drawn through a filter in a face-mask by the wearer's breathing action, to sophisticated powered systems which supply clean air at a regulated positive pressure. In all cases, because some form of face-mark or hood must be worn communication by the wearer is severely restricted. The invention provides breathing protection equipment including acoustic coupling to a remotely located microphone. The microphone may, for example, be contained together with its electrical supply and a transmitter in the wearer's breast pocket, and be connected with the face mask of the breathing protection equipment by means of a flexible sound pipe. These arrangements place the microphone, and all other electrical parts remotely from the mask. Among other things this facilitates regular cleaning of the mask, and may improve the reliability of the system generally.

Description

Λ COMMUNICATION INTERFACE FOR BREATHING EQUIPMENT Technical Field
This invention concerns all types of breathing protection and diving equipment, ranging from simple passive systems where air is drawn through a filter in a face-mask by the wearer's breathing action, to sophisticated powered systems which supply clean air at a regulated positive pressure. In all cases, because some form of face-mask or hood must be worn, communication by the wearer is severely restricted. Background To address the problems of communication while wearing a breathing protection mask, electrical connectors and microphones have been introduced into the masks. Disclosure of the Invention
The invention provides breathing equipment including a face part that in use is adjacent at least the mouth of the wearer, the face part being associated with acoustic coupling to a remotely located microphone. The breathing equipment may be used for breathing protection or diving applications.
The microphone may, for example, be contained together with its electrical supply and a transmitter in the wearer's breast pocket, and be connected with the face mask of the breathing protection equipment by means of a flexible sound pipe. These arrangements place the microphone, and all other electrical parts remotely from the mask. Among other things this facilitates regular cleaning of the mask, and may improve the reliability of the system generally.
The acoustic coupling may comprise a sound pipe which may be made of simple flexible tubing, such as tubing made from plastics materials.
A face mask may act as a pressure box and the upper end of the sound pipe can be positioned within the mask cavity. The sound pipe may enter the cavity through a port fabricated in the mask, or through the air supply valving.
Alternatively, the sound pipe may have a flared end to funnel the sound pressure waves caused by speech into the pipe.
A membrane may be provided over the upper end of the sound pipe to prevent moisture or other material from entering it. At the lower end the sound pipe may be sealed into a package which also contains the microphone, to provide good transfer of Ihe sound pressure to the microphone. The seal is preferably pneumatic, but if there were a small hole the system will still function. The pressure transmission medium in the pipe may be gaseous or liquid.
The cut off frequency for an acoustic coupling pipe is proportional to its diameter, and the medium in the pipe. A tube of 50mm diameter in air will have a cut off frequency of approximately 3KHz, which is just sufficient for the transfer of intelligible speech. An important advantage of the invention arises from having the speaker and the remote microphone both located in essentially the same pressure chamber. The pressure chamber is split into two compartments which are connected together by the acoustic coupling. The acoustic coupling may provide either an hydraulic or pneumatic link to maintain the two compartments at the same pressure, and this enables a pipe of small diameter to be utilised for the acoustic coupling.
Specifically the diameter of the pipe may be less than that expected to be required by consideration of the diameter and the medium, because of the equal pressures at either end.
In order to cancel ambient noise, two microphones may be connected in a noise cancelling arrangement. The first microphone may pick up the noise pk s the speech signals, and the second microphone may be arranged to pick up only the noise signals. An electronic circuit will subtract the two signals in order to provide a clean speech signal. Brief Description of the Drawings: An example of the invention will now be described with reference to:
Figure 1 which is a schematic illustration of an embodiment of the invention; and
Figure 2 which is a circuit diagram showing electrical treatment of the sound signals picked up by the embodiment of Figure 1. Disclosure of the Best Modes of the Invention
Referring first to Figure 1 the breathing protection equipment 1 comprises a face mask 2 with some kind of air supply port 3. A sound pipe 4, comprising clear PVC having a inner diameter of 1.5mm, penetrates the mask and terminates in a flared funnel 5 within the mask cavity 6. A membrane 7 covers the open end of the funnel 5. At the lower end, sound pipe 4 is pneumatically sealed in a cavity 8 together with a microphone 9, by means of an adaptor 10. By this means the sound pressure change inside the sealed breathing mask cavity 6 are pneumatically communicated to the sealed cavity 8 and microphone 9 via the air in the sound pipe 4.
A second microphone (not shown) is also associated with the lower end of the sound pipe, however, this microphone only picks up ambient noise and does not receive any of the sound communicated by sound pipe 4. Referring now to Figure 2, the speech and noise signal 11 from microphone 8 is fed to the non-inverting input of an amplifier 12, and the noise signal 13 picked up by the second microphone is fed to the inverting input of amplifier 12. Amplifier 12 subtracts the noise signal from the speech and noise signal to output a clean speech signal 14.
Although the invention has been described with reference to a particular example, it should be appreciated that it may be embodied in many other forms. In particular it should be appreciated that the invention is not restricted to breathing protection equipment of the type which involves use of a face mask, and it may be applied to those systems where there is no mask cavity, such as hoods or visors. In those situations the flare at the upper end of the sound pipe is adapted to provide a sound pick Lip (or collection) cavity. When a mask is used the flare may be dispensed with, since the mask cavity will act as a sound collector.
It should also be appreciated that the invention will operate with sound pipes of diameters with a broad range of inner diameters less than about 50mm. Inner diameters of between 1 and 5mm have been found to operate well. The sound pipe could also be used for air stipply in which case a wider diameter could be used.
It will be appreciated by persons skilled in the art that numerous variations and/or modifications may be made to the invention as shown in the specific embodiments without departing from the spirit or scope of the invention as broadly described. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive.

Claims

CLAIMS:
1. Breathing equipment including a face part that, in use is adjacent at least the mouth of a wearer, the face part being associated with acoustic coupling means which provide acoustic coupling to a remotely located microphone.
2. Breathing equipment according to claim 1, wherein the breathing equipment is breathing protection equipment.
3. Breathing equipment according to claim 1, wherein the breathing equipment is breathing diving equipment.
4. Breathing equipment according to claims 1, 2 or 3, wherein the equipment comprises a mask, visor or hood.
5. Breathing eqmpment according to my preceding claim, wherein the acoustic coupling means comprises a sound pipe.
6. Breathing equipment according to claim 5, wherein the sound pipe is made of flexible tubing.
7. Breathing equipment according to claim 6, wherein the remote end of the sound pipe enters a compartment which also contains the microphone.
8. Breathing equipment according to claim 7, wherein the compartment together with the face part comprise a single press ire chamber.
9. Breathing equipment according to claim 5, wherein there is a gaseous or liquid pressure transmission medium in the sound pipe.
10. Breathing equipment according to claim 1, wherein the local end of the acoustic coupling, which is associated with the face part, terminates in a sound collector.
11. Breathing equipment according to claim 10, wherein a membrane is provided over the upper end of the sound pipe.
12. Breathing equipment according to claim 10, wherein the sound collector is a flared upper end of the sound pipe.
13. Breathing equipment according to claim 10, wherein the sound collector is a mouth covering mask.
14. Breathing equipment according to claim 13, wherein the sound pipe enters the mask through a port.
15. Breathing equipment according to claim 13, wherein the sound pipe enters the mask through inhalation or exhalation valving. IG. Breathing equipment according to any preceding claim, wherein two microphones are connected in a noise cancelling arrangement. 17. Breathing equipment according to claim 16, wherein a first microphone picks up noise plus speech signals, and a second microphone is arranged to pick up only the noise signals; an electronic circuit subtracts the two signals in order to provide a clean speech signal.
PCT/AU1997/000216 1996-04-04 1997-04-03 A communication interface for breathing equipment WO1997037724A1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AU21456/97A AU2145697A (en) 1996-04-04 1997-04-03 A communication interface for breathing equipment

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
AUPN9155A AUPN915596A0 (en) 1996-04-04 1996-04-04 A communication interface for breathing protection equipment
AUPN9155 1996-04-04

Publications (1)

Publication Number Publication Date
WO1997037724A1 true WO1997037724A1 (en) 1997-10-16

Family

ID=3793469

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/AU1997/000216 WO1997037724A1 (en) 1996-04-04 1997-04-03 A communication interface for breathing equipment

Country Status (2)

Country Link
AU (1) AUPN915596A0 (en)
WO (1) WO1997037724A1 (en)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2786107A1 (en) * 1998-11-25 2000-05-26 Sextant Avionique Oxygen mask with sound pick-up, e.g. for pilot of combat aircraft, has horn with opening immediately in front of wearer's mouth
GB2371493A (en) * 2001-01-29 2002-07-31 Davies Ind Comm Ltd Microphone adaptor for a respirator
WO2008081226A1 (en) * 2007-01-04 2008-07-10 Intertechnique Acoustic sensor for use in breathing masks
FR2942127A1 (en) * 2009-02-16 2010-08-20 Centre Nat Rech Scient Pneumotachographic device for use in pneumotachographic and acoustic data recording system in hospital in e.g. phonetic field, has mask presenting sufficient aerodynamic resistance for creating differential pressure
CN107610689A (en) * 2016-07-12 2018-01-19 张焕祯 Sound arrester

Citations (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR828843A (en) * 1937-02-08 1938-05-31 Const Electro Mecaniques D Asn Improvements to masks, diving suits, helmets or similar
US3184556A (en) * 1961-12-11 1965-05-18 Pacific Plantronics Inc Miniature headset-microphone adapted for use with a mask
US4013992A (en) * 1976-01-28 1977-03-22 The United States Of America As Represented By The Secretary Of The Navy Diver's piezoelectric microphone with integral agc preamplifier
GB2058578A (en) * 1979-08-07 1981-04-15 Secr Defence Improvements in or relating to breathing apparatus
GB2084428A (en) * 1980-09-18 1982-04-07 Gentex Corp Local external communication device for enclosed helmet and mask assembly
WO1982003160A1 (en) * 1981-03-20 1982-09-30 Francois Chaise Device for communicating between users of a vehicle
US4537276A (en) * 1984-09-07 1985-08-27 American Sterilizer Company Mask/microphone system for voice actuated control
EP0377316A2 (en) * 1989-01-05 1990-07-11 Walter R. Noetzel Voice communication unit
WO1991007859A1 (en) * 1989-11-08 1991-05-30 Actron Manufacturing Company Voice transmission system
WO1991012051A1 (en) * 1990-02-16 1991-08-22 Hök Instrument Ab Acoustic respiration detector
WO1994005372A1 (en) * 1992-09-01 1994-03-17 Bretagne Radio Communications Communication device for use with a respiratory unit

Patent Citations (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR828843A (en) * 1937-02-08 1938-05-31 Const Electro Mecaniques D Asn Improvements to masks, diving suits, helmets or similar
US3184556A (en) * 1961-12-11 1965-05-18 Pacific Plantronics Inc Miniature headset-microphone adapted for use with a mask
US4013992A (en) * 1976-01-28 1977-03-22 The United States Of America As Represented By The Secretary Of The Navy Diver's piezoelectric microphone with integral agc preamplifier
GB2058578A (en) * 1979-08-07 1981-04-15 Secr Defence Improvements in or relating to breathing apparatus
GB2084428A (en) * 1980-09-18 1982-04-07 Gentex Corp Local external communication device for enclosed helmet and mask assembly
WO1982003160A1 (en) * 1981-03-20 1982-09-30 Francois Chaise Device for communicating between users of a vehicle
US4537276A (en) * 1984-09-07 1985-08-27 American Sterilizer Company Mask/microphone system for voice actuated control
EP0377316A2 (en) * 1989-01-05 1990-07-11 Walter R. Noetzel Voice communication unit
WO1991007859A1 (en) * 1989-11-08 1991-05-30 Actron Manufacturing Company Voice transmission system
WO1991012051A1 (en) * 1990-02-16 1991-08-22 Hök Instrument Ab Acoustic respiration detector
WO1994005372A1 (en) * 1992-09-01 1994-03-17 Bretagne Radio Communications Communication device for use with a respiratory unit

Cited By (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2000030716A1 (en) * 1998-11-25 2000-06-02 Thomsom-Csf Sextant Oxygen inhaler mask with sound pickup device
AU756473B2 (en) * 1998-11-25 2003-01-16 Thomsom-Csf Sextant Oxygen inhaler mask with sound pickup device
US6997178B1 (en) 1998-11-25 2006-02-14 Thomson-Csf Sextant Oxygen inhaler mask with sound pickup device
FR2786107A1 (en) * 1998-11-25 2000-05-26 Sextant Avionique Oxygen mask with sound pick-up, e.g. for pilot of combat aircraft, has horn with opening immediately in front of wearer's mouth
US7493899B2 (en) * 2001-01-29 2009-02-24 Selex Comunications Limited Microphone adaptor for a respirator
GB2371493A (en) * 2001-01-29 2002-07-31 Davies Ind Comm Ltd Microphone adaptor for a respirator
GB2371493B (en) * 2001-01-29 2005-02-02 Davies Ind Comm Ltd A microphone adaptor for a respirator
WO2008081226A1 (en) * 2007-01-04 2008-07-10 Intertechnique Acoustic sensor for use in breathing masks
CN101600478B (en) * 2007-01-04 2012-01-18 联合技术公司 Acoustic sensor for use in breathing masks
US9950201B2 (en) 2007-01-04 2018-04-24 Zodiac Aerotechnics Acoustic sensor for use in breathing masks
FR2942127A1 (en) * 2009-02-16 2010-08-20 Centre Nat Rech Scient Pneumotachographic device for use in pneumotachographic and acoustic data recording system in hospital in e.g. phonetic field, has mask presenting sufficient aerodynamic resistance for creating differential pressure
CN107610689A (en) * 2016-07-12 2018-01-19 张焕祯 Sound arrester
CN107610689B (en) * 2016-07-12 2020-08-07 张焕祯 Sound absorbing device

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