Language selection

Search

Patent 1306925 Summary

Third-party information liability

Some of the information on this Web page has been provided by external sources. The Government of Canada is not responsible for the accuracy, reliability or currency of the information supplied by external sources. Users wishing to rely upon this information should consult directly with the source of the information. Content provided by external sources is not subject to official languages, privacy and accessibility requirements.

Claims and Abstract availability

Any discrepancies in the text and image of the Claims and Abstract are due to differing posting times. Text of the Claims and Abstract are posted:

  • At the time the application is open to public inspection;
  • At the time of issue of the patent (grant).
(12) Patent: (11) CA 1306925
(21) Application Number: 1306925
(54) English Title: EXHALATION DUCT
(54) French Title: CONDUIT D'EXHALATION
Status: Expired and beyond the Period of Reversal
Bibliographic Data
(51) International Patent Classification (IPC):
  • A62B 9/00 (2006.01)
(72) Inventors :
  • SCHRIVER, JOHN G. (United States of America)
  • RIFFEL, WILLIAM L., JR. (United States of America)
  • SCHEIBLE, JOHN D. (United States of America)
(73) Owners :
(71) Applicants :
(74) Agent: JOHN LAMBLAMB, JOHN
(74) Associate agent:
(45) Issued: 1992-09-01
(22) Filed Date: 1989-04-28
Availability of licence: N/A
Dedicated to the Public: N/A
(25) Language of filing: English

Patent Cooperation Treaty (PCT): No

(30) Application Priority Data: None

Abstracts

English Abstract


ABSTRACT
An exhalation duct is formed from a gas impermeable
covering layer having spacer material extending through the length
of the duct to define a substantially cylindrical opening. A
lower end of the duct is formed with a plurality of exhalation
holes or openings in the covering layer and an elastic end
receiving the air supply hose of a self-contained air supply
breathing apparatus. The upper end of the exhalation duct seals
to an exhalation valve of breathing apparatus to direct exhalation
air from the mask, entirely through the duct, for discharge
through the holes formed in the lower end. In operation, the
lower end of the exhalation duct is positioned within the torso
area of a protective hood jacket to prevent internal fogging of
the hood jacket mask.


Claims

Note: Claims are shown in the official language in which they were submitted.


THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. Exhalation duct comprising a spacer material defining a
generally cylindrical passage; a covering layer extending around
the spacer material, said covering layer being gas-impermeable,
one end of said duct having means for sealing the upper end
thereof to an exhalation valve and the lower end of the duct
having means for discharging air from the exhalation valve through
at least one discharge opening in the lower end.
The exhalation duct of Claim 1, wherein the upper duct
end sealing means includes a rubber seal member having first and
second openings for respectively receiving an air supply hose and
an exhalation valve of a breathing mask.
3. The exhalation duct of Claim 2, wherein the opposite end
of the duct includes an elastic end for receiving therethrough the
air supply hose, and wherein said at least one discharge opening
is a plurality of openings formed in the covering layer
substantially only at a lower end thereof.
4. The exhalation duct of Claim 1, wherein said sealing
means includes an annular sealing member having a central opening
adapted to fit around an exhalation valve of a breathing mask.
5. The exhalation duct of Claim 1, wherein the spacer
material and covering layer is in the form of a corrugated rubber
-17-

hose and wherein the sealing means is in the form of a molded
rubber or the like valve covering having clamping means for
securing an upper end of the hose to an outlet of said valve
covering.
-18-

Description

Note: Descriptions are shown in the official language in which they were submitted.


The present invention relates generally to apparatus for
protecting workers from percutaDeous poisoning and toxic
environments. More particularly, the invention relates to an
exhalation duct for a hood jacket worn over self-contained
breathing apparatus to enable the wearer to perform tasks within a
toxic environment without fogging the mask of the breathing
apparatus.
It is an object of the present invention to provide
apparatus for venting exhaled air from an enclosed hood forming
part of a protective garment whIle preventing fogging of the hood
lens and minimizing any exposure of the wearer to outside
contaminated air.
The present invention also provides an exhalation duct
that can be easily worn within a hood-jacket as part of a
protective ensemble, i.e., a rocket fuel handler suit, rubber
boots, rubber gloves, and a self-contained breathing apparatus
worn within the hood-jacket. It is inexpensive to manufacture,
comfortable to wear, and vents exhaled breath from the hood
interior to within the jacket portion of the protective garment.
Different forms of exhalation ducts can be used to accommodate
various types of breathing apparatus.
Other objects of the invention are realized in a
preferred embodiment of this invention with an exhalation duct
that is generally flexible along its length and has one end with
sealing means providing sealing contact with the exhalation valve
of a face mask of a breathing apparatus, and an opposite end
provided with openings for directing exhalation gas outwardly from
the duct. The inner diameter of the duct is greater than the

13~6~
outer diameter of an air supply hoæe extending through the duct
and sealing end for connecting the inlet valve of the breathing
mask to a source of bottled air carried on the wearer's back.
Preferably, the exhalation duct is formed of a spacer
material defining a generally cylindrical duct. The spacer
material has sufficiently rigid properties in the radial direction
of the duct so as to maintain the interior region of the duct open
along its entire length, i.e., without blockage. A protective
covering is provided around the spacer material. The lower or
discharge opening of the duct may be provided with vent holes for
venting exhalation air into the jacket portion of the garment.
The lower end of the duct also preferably includes an elastic end
opening to enable easy insertion of the air supply hose through
the duct for suhseguent connection to the BA mask.
The upper sealed opening of the duct may take different
forms depending upon the particular configuration of the
exhalation valve and air supply connector of a BA type mask. In
one embodiment, the sealed opening includes a seal member having a
first opening connectable to the exhalation valve located below
the face mask and a second smaller opening through which the air
supply hose extends for connection to the mask. In another
embodiment, the upper sealed opening is a valve cover formed of
flexible material adapted to fit entirely around the mask
regulator. A corrugated rubber or flexible hose is attached to
;the exhalation valve cover and has an inner diameter greater than
the outer diameter of the air supply hose.
The exhalation duct of the present invention may be
utilized with any type of protective garment wherein a BA mask is
.
- 2 - ;

worn by the user wherein fogging of the mask exterior is a
problem.
Other aspects of the present invention will become
readily apparent to those skilled in this art from the following
description wherein there is shown and described a preferred
embodiment of thls invention simply by way of illustration of the
best mode contemplated for carrying out the invention. As will be
reali~ed, the invention is capable of other embodiments, and its
several details are capable of modifications in various obvious
respects, all without departing from the invention. Accordingly,
the drawing and description will be regarded as illustrative in
nature and not as restrictive.
The invention will now be described with reference to
the accompanying drawings in which:
Figure 1 is a perspective view of a hood-jacket and the
exhalation duct of the present invention worn in combination with
a BA mask;
Figure 2 is a front plan view of the hood-~acket;
Figure 3 is a rear plan view of the hood-~acket
; 20 illustrating various primary and secondary seals of the jacket;
Figure 3A is a partial perspective rear view of the
interior of the hood portion depicting the neck collar barrier and
cone seal configuration;
Figures 3B, 3C and 3D are partial perspective views of
the cone seal configuration in open, partially closed and fully
closed positions, respectively; and
Figure 3R, located on the same sheet as Figure 3A, is a
partial perspective side elevational view of the cone seal of
, , ~

-~L3~a~:~;
Figure l7.
Figure 4 is a side elevational view of a first
embodiment of an exhalation duct in accordance with the present
invention;
Figure 5 is a sectional view taken along the :Line 5-5 of
Figure 4;
Figure 6 is a sectional view taken along the line 6-6 of
Figure 5;
Figure 7 is a detailed top plan view of the sealing end
of the exhalation duct of Figure 4;
Figure ~ is a detailed plan view of the venting lower
end of the exhalation duct of Figure 4;
Figure 9 is a sectional view taken along the line 9-9 of
Figure 8;
Figure 10 is a cross-sectional view of the duct of
Figure 4;
Figure 11 is a view of the manner in which the spacer
material and cover forming the exhalation duct are sealed together
along the length of the duct;
20Figure 12 is a detailed bottom plan view of the sealln~
end of the Figure 4 exhalation duct;
Figure 13 is a perspective view of a type of BA mask
used in conjunction with the exhalation duct of Figure 4;
Figure 14 is a detailed side plan view of an exhalation
duct in accordance with a second embodiment of the present
invention;
Figure 15 is a sectional view taken along the line 15-15
of Figure 14;
-- 4 --

6~
Figure 16 is a perspective view of a type of BA mask
worn in conjunction with the ~igure 14 embodiment of the
invention;
Figure 17 is a perspective view of a third type of mask;
Figure 18 is a detailed elevational view o~ an
exhalation duct in accordance with a third embodiment of the
invention worn in conjunction with the mask of Figure 17; and
Figure 19 is a top plan view of the upper sealing end of
the exhalation duct of Figure 18.
In Figures 1 - 3 there is disclosed a hood-jacket 10
formed with a hood portion 10b and iacket portion lOa preferal~ly
made of panels of C~ILOROP~I,* fabric heat-sealed together to form a
single protective garment. ~ood-~acket 10 as best illustrated in
Figure 1, is worn over a self-contained air supply hreathing
apparatus (such as the M23A1 type self-contained air supplied
breathing apparatus) which breathing apparatus generally comprises
an air cylinder 12 strapped to the wearer's back, a regulator
assembly 14 having various instrument gauges (not shown in detail)
strapped to the wearer's waist and a face mask 16 connected to
regulator 14 with air hose 18 extending upwardly along the
wearer's chest region for connection to an inlet valve 16a of the
; mask. As will he seen more fully below, hood-jacket 10 is
designed to fit over the M23Al type BA illustrated in the drawings
as well as other BAs. ~ood jacket 10 is also designed to fit any
wearer, re~ardless of size.
As will be seen more fully below, hood-jacket 10 is
preferably formed from panels of material resistant to toxic
chemicals, which panels may be heat-sealed together along their
-- 5
* Trademark
-
- ,
:~ . .
~. . ` : ~

~a~
peripheries to form the basic garment of the hood-~acket. A
plastic vinyl material is used to form a visor 20 which is easily
heat-sealed along its periphery to the fabric panels forming the
hood portion lOb. The hood-~acket 10 is preferably of hip length
and short-sleeved. There may be a large hump 22 (Figure 1) formed
in the rear portion of the ~acket lOa to accommodate air cylinder
12 of the BA and to allow for forward bending.
There is a comhination closure in the back of jacket
portion lOa, as best depicted in Figure 3, comprising a metal
zipper 23 and a ~HLOROP~* zip-loc closure 25 for seaLable opening
and closing of the jacket portion rear for air bottle replacement
and donning/doffing of the garment.
In addition to the foregoing seals 23, 25, vapor leakage
is in general mechan~cally reduced by two types of seals within
hood-Jacket 10 of the invention. The first type, as will be seen
below, encompasses the garment peripheries at the hip and sleeve
ends. These seals incorporate cable drawstrings and are
adjustable. The second type constitute internal collars, a few
inches up from the ends of the sleeves and around the waist and
2n neck. These elastic collars are also self-ad~ustable. The
elastic collar inside the hood, in the neck area, is designed to
further reduce vapor infiltration into the area. This collar may
~ Lc Ro ~
have a frontal ~e~e~ closure which fastens around the ~A mask
inlet air tube.
As discussed above, hood portion lOb is that portion of
hood-jacket 10 which is worn over the head. Hood portion lOb is
preferably a combination of chlorinated polyethylene plastic
material and, in particular fabric panels 26 thereof which ma~ be
* Trademark

heat-sealed together as at 27 (Figure 3). The panels 26 are also
heat-sealed to visor 20 as depicted in Figure 2. Visor 20,
preferably made from such as polyvlnyl chloride (PVC*) o~
transparent optical quality, may constitute a major portion of
hood lOb to provide for optimum viewing conditions by the wearer.
The torso or Jacket portion lOa of hood-jacket 10 is
also formed of chlorinated polyethylene fabric panels 2fia that may
be heat-sealed together at their peripheries (see Figure 3) as at
29 to form the basic jacket configuration. ~ pair of sleeves 30
ln also preferably formed of chlorinated polyethylene heat-sealable
plastic material are heat-sealed to the fabric panels 26a of
~acket portion lOa (see, e.g., Figure 3). The hood ancl ~acket
fabric panels 26, 26a and visor 20 are then heat-sealed together
as depicted in Figure 2 to form the baslc outer garment of the
hood-jacket. A chlorinated polyethylene fabric strip 33 (Figure
2) may be used to connect the hood or visor and jacket fabric
panels together in heat-sealing relationship.
~ n anti-fog kit schematically shown at 35 may be fixed
to a portion of fabric panels 26 of hood lOb outside seal 27 as
depicted in Figure 3. More specifically, anti-fog kit 35 is
secured to a grommet 37 heat-sealed to fabric panel portions 26
atop the hood and sècured thereto by string 37a. Anti-fog kit 35
consists of instructions, an anti-fog compound and a wiping cloth
all enclosed in a plastic bag 35a. The compound is a medium hard
wax-type substance that is applied like a crayon over the inner
surface of visor 20 and gauge viewing windows 39 and 41 discussed
infra~ The compound is then rubbed with the fingers to cover the
entire areas and the excess is removed by means of the wiping
- 7
* Trademark
,

)6~5
cloth. Its purpose is to reduce Eogging of the inside of visor
surfaces for clearer ~ision.
Oval gauge window 39 and square gauge window 41 are both
assembled in the front part of jacket portion 10a, as depicted in
Figure 2. Their function is to allow the user to view the front
mounted pressure gauges forming part of regulator 14 of the BA
worn beneath the hood-jacket 10. It is to be noted that each of
the windows 39 and 41 is preferably made of the same PVC* material
as visor 20 and heat-sealed into the fabric panels 26a of the
jacket.
With reference now to Figure 3, the combination closure
25 is heat-sealed in the rear of jacket portion 10a and comprises
an inner metal zipper 23 and an outer double channel ZIP-LOC*
plastic zipper (not shown in detail) 40 providing a good
mechanical seal. The functions of zippers 23, 40 are to establish
an opening in the rear of jacket portion 10a on each half thereof
for donning/doffing the hood-jacket 10 and for access to air
cylinder 12 for .replacement, without removing the garment. For a
good air-tight seal, the two channels of ZIP-LOC* 40 are
preferably filled with petroleum jelly on one side prior to
donning. The ZIP-LOC* 40 may be opened by grasping adjacent pull
tabs 42a and 42b starting at the bottom of the jacket to pull the
ZIP-LOC* apart. The tabs 42a, 42b are mountd on reinforcement
fabric strips 43 which overlap fabric panels 26 to provide a one
inch in width heat seal all around the closure opening (Figure 3).
The double plastic channels 40 of the ZIP-LOC* plastic zipper are
fixed to these reinforcement panels as depicted in Figure 3.
Waist draw cord 47 is pulled tight to the waist of the
* Trademark
.
.

wearer and held ln place by a B-lock* fastener 49~ Waist collar
barrier 5Q is pulled snug about the waist higher than the draw
cord 47 and fastened hy means of hook and pile fasteners 51 and 53
sewn to the ends of the waist collar barrier. The waist collar
b~rrier is preferably formed by a piece of elastic webbing
positioned within a channel formed by an overlapping lower edge of
the fabric panel at 57. Waist draw cord 47 is also formed within
a channel formed by overlapping a piece of Eabric panel 26a and
then heat-sealin~ the same together.
The neck collar barrier 70 is also defined by a piece of
elastic wehhing 72 received within a closed channel 73 formed in a
chlorinated polyethylene length of material 74 having heat-sealed
overlapping edges which material is also heat-sealed to fabric
panels 26a. The neck collar barrier 70 is thereby located inside
hood-jacket 10 at the base of hood lOb to effect a seal between
the inside of the jacket area and the hood.
The waist draw cord 47 and the sleeve draw cord 60 are
the initial means of producing an air-tight seal. The waist
collar barrier and the sleeve collar barrier 65 are secondary
seals to prevent leakage into the jacket area. The waIst, sleeve
and neck collar barriers are preferably made of a thinner
chlorinated polyethylene material which are heat-sealed to the
inside of the hood-jacket fabric panels 26, 26a in the areas shown
and have elastic wehbing affixed to the inner portion which fits
snug to those portions of the wearer's body. The neck collar
barrier 70, which fits snuggly to the neck above the collar of the
wearer's protective suit worn beneath, prevents any leakage in the
jacket area from entering the hood area.
_ 9 _
* Trademark
- '
, '

- ~l3~
Neck collar barrier 70 preferahly includes a split cone
configuration lOO in the center oF the front portion of the
barrier material. The purpose of the split cone is to provide a
means of sealing around the air supply hose lô of the BA and the
exhalation duct. The air hose 18 extends from the waist area up
to the air mask 16 on the wearer's face. The exhalation duct hose
(not shown) extends from the mask down into the chest area of the
hood-jacket. A seal is effected around the air hose 18 and
exhalation duct by the wrap around cone seal lOn and fastenetl in
place by vertical and wrap around hook and pile fasteners.
More specifically, and with reference to Figures 3A-3~,
the cone seal 100 is formed of neck collar barrier material
(similar to the material forming collar 70) 102 folded into a cone
shape having an upper diameter greater than the lower diameter.
The cone seal 100 is open as at 104, the opening being defined by
two edges 106a and 106b extending the entire length of the cone.
A snap fastener having mating halves 108a and 108b are located at
the top of each edge 106a and 106b, respectively~ and hook and
pile fastener strips 110 and 112 (e.g., VRRCRO~) are secured on
the inner vertical surface of seal material 102 adjacent the edges
106a and 106b. Tightening straps 114 having hook material 116 on
one side and pile material 118 on the opposite side are vertically
spaced ~rom each other and secured to lower and middle portions of
the cone seal.
Once the air hose and exhalation duct are positioned
through the center of the cone seal 100, the vertical sides or
edges 106a and 106b are wrapped snugly around the air hose and
exhalation duct and the open edges 106a and 106b are brought
-- 10 --
* TraAemark
-- .

~.3~
together. The inside vertical hook and pile straps 110 and 112
contact each other and hold the cone in the Figure 3C position.
The fina] closure and seal is effected hy snapping the fastener
halves 108a and lO~b together and wrapping the two adjustment and
tightening straps 114 around the cone. The length of the straps
116 is sufficient so that the hook surface 116 on one side of the
cone will contact the pile surface 118 on the other side so that
the cone seal is Eully closed as depicted in Figure 3D in sealing
contact with the air hose and exhalation duct.
The next seal 100 is secured to neck collar barrier 70
such as with stitching along the upper edges of the cone material
102. The cone suspends freely below the neck collar barrier 70 as
depicted in Figure 3A and the partial side elevation view of
Fi~ure 3R.
The hood-jacket 10 of our invention has a unique
combination of internal seals, such as the cable draw cords and
internal collar barriers, which together with the overall
hood-jacket configuration achieve an extremely tight fit resulting
in essentially no internal leakage. The hood jacket l0 and BA are
designed to be worn over protective rubber suits which are in
current use. There may be a very small amount of leakage
depending on the physical activity of the wearer, which may get
past the draw cord and collar barrier seals of the waist and
sleeve and into the torso area. ~owever this occurs, it is
contained between the outside of t~e protective suit and inside of
the ~acket part of the garment and the neck collar barrier. There
is no wearer's skin exposed in this area.
Because of the neck collar seal 70, there tends to be a
, , : . ,

huildup of moisture inside the enclosed hood of the hood-jacket
lO. This moisture disadvantageously causes fogging of the inside
of the hood lens 20. The moisture buildup results from not only
the perspiration of the skin of the wearer's head and neck, but
also from the exhaled breath of the RA. Fogging caused by
perspiration is somewhat controllable and, in any event, does not
significan~ly contribute to the fogging problem. ~owever, exhaled
breath, which contains more than 60~ moisture, is the most
significant factor contributing to the Fogging problem. This can
be eliminated by venting exhaled breath outside of the enclosed
hood. Venting throu~h the hood wall to the outside involves
sensitive valve assemhlies and possibly dangerous backflow of
contaminated outside air, and is therefore disadvantageous.
To avoid the disadvantage associated with the apparatus
of Figures 1 to 3 an exhalation duct 120, as shown in Figures 4 -
7, has been designed for use in conjunction with the breathing
apparatus depicted in Figure 13 (commonly known as a Mine Safety
Appliances BA, Model 401). The exhalation duct 120 comprises a
coverin~ 122 formed, for example, from a lightweight butyl coated
cloth surrounding layers of spacer material 124 which may be very
porous and substantially entirely enclosed by the cover 122. A
rubher seal 126 is formed at one end of exhalation duct 120. The
rubber seal 126 will define the upper end of the exhalation duct
located within the hood portion lOb of hood jacket 10. The rubber
seal 126, as best depicted in Figure 12, includes a rubber sheet
128 formed with a first hole 130 adapted to receive the exhalation
valve of the breathing apparatus and a second smaller hole 132
adapted to receive the inlet air hose 18 in sealing contact
- 12 -

6~
therewith.
The opposite or lower end 1~ is an elastic end provided
with a series of vent or exhalation holes 136 formed within the
covering 122.
In operation, the a1r supply hose 18 of the breathing
apparatus is inserted through elastic end 134, through the spacer
material 124 and out the sma]l hole 132 in the rubber seal 128 at
the opposite or upper end. The air supply hose 18 is then
reconnected to the mask and the large hole 130 of the rubber seal
is stretched over the outlet valve of the mask, as described
supra. The rubber seal 12~ is adjusted up over the air hose
connector and outlet valve. It is then pushed flush to the face
piece. The exhalation duct is then fitted through the cone seal
100 and stretched along the torso such that the elastic end 134
terminates proximate the lower chest or abdominal area of the
wearer. Thus, in operation, exhaled air is captured by the rubber
seal and directed through the porous circular spacer material
layers 124 along the length of the duct 120 and out through the
e~halation holes 136 into the torso area. The seal 128 and
covering 122 prevents exhaust air from entering either the hood
portion 10b or upper torso area of the hood ~acket portion 10a,
i.e., the exhaled air is forced to flow entirely through the
porous material of the exhalation duct until it reaches holes 1360
Incoming air is brought through the hose 18 into the ~àsk area as
discussed supra.
The spacer material 124 has sufficiently rigid
properties in the radial direction of the duct 120 so as to
maintain the interior region of the duct open along its entire
- 13 -

length, i.e., without blockage. The elastic end 134 enables easy
insertion of the air supply hose through the duct for subsequent
connection to the BA mask as discussed supra.
With reference to Figures 5-7, it can he seen that the
upper portion of exhalation duct 120 is formed with a plurality of
spacer material layers 124 to ensure that the generally
cylindrical duct has sufficiently rigid properties in the radial
direction thereof and in the upper portion so as to prevent
blockage or excessive compression that might be caused by the cone
seal lnO or by flattening of the up~er portion of the duct by the
wearer's upper torso that might otherwise impede the flow of
exhalation air from the mask to the elastic end 134. As depicted
in Figure 6, the lower portion of the duct 120 may be formed with
a single layer of spacer material 124.
The covering 122 may be stitched and heat-sealed to the
outer periphery of seal 128, as depicted in Figures 5 and 12.
With reference to Figures 10 and 11, the covering 122 and spacer
material layer 124 may be stitched together along their opposite
longitudinal edges and heat-sealed to define a sealed seam
; 20 extending the length of the duct 120. With reference to Figure 9,
the portion of duct 120 in the region of exhalation holes 136 May
include a cloth material, such as butyl coated cloth that
sandwiches the spacer material 124 in cooperation with covering
122. Edges 138 and 139 of cloth 140 and covering 122 respectively
may overlap each other for stitching and heat-sealing together
with elastic material 142 completing the elastic end 134 (Figure
9).
Figures 14-16 are illustrations of a second embodiment
- 14 -

of an exhalation duct 145 according to the present invention which
is substantially identical to exhalation duct 120 of the first
embodiment except at its upper encl 147 providing sealing contact
with a ~&~i~re Mark I BA depicted in Figure 16. Thus, with
reference to Figure 15, the upper end 147 has the upper ends of
covering 122 and spacer material 124 stitched and sealed together
with further stitching and sealing at 149 to an annular rubber
seal 150. The SURVIVAIRE* BA of Figure 16 has the exhalation
valve in front of and slightly below the chin and the air supply
hose connector directly below it. This duct 145 is assembled to
the BA in the same manner as duct 120. The air supply hose of the
BA is inserted through the spacer material and out through the
rubber seal 147. However, after the air hose 18 is connected to
the face mask, the ruhber seal 147 having a single central opening
(not shown) is stretched over both the air hose connector and the
exhalation valve and adjusted flush to the mask. Otherwise, the
duct 145 functions exactly as that of the duct 120 of the first
embodiment.
Figures 17-19 are illustrations of a third embodiment of
the invention wherein an exhalation duct 155 is used in
conjunction with a SCOTT PRESUR PAK* 4.5 breathing apparatus
depicted in Figure 17. The principal end function of this duct
155 is the same as ducts 120 and 145, although the configuration
is different. The regulator 157 of the Scott breathing apparatus
is mounted on the front of the mask and appears as a cylindrical
can in shape. The exhalation valve is loca~ed at the back and
bottom of the air regulator 157, facing the mask. The exhalation
duct 155 comprises an exhalation valve cover 159 of molded rubber
*Trade Mark

which fits over the entire air regulator 157 Inserted into the
rubber cover through opening 160 defined by inturned edges 162. A
corrugated rubher hose 164 connected to an outlet opening 166 of
valve cover 159 via bushing 168 and clamp 170 is adapted to extend
through cone seal 164 to direct exhalation gas through the hose
into the torso area. Although not shown, the valve cover 159 may
have openings on either side of bushing 168 which respectively
accommodate the smaller diameter air supply hose 18 and a purge
valve.
It should be apparent from the preceding that this
invention may be practiced otherwise than as specifically
described and disclosed herein. Modifications may therefor he
made to these specific embodiments disclosed here without
departing from the scope of this invention and such as intended to
be included within the appended claims.
- 16 -
-

Representative Drawing
A single figure which represents the drawing illustrating the invention.
Administrative Status

2024-08-01:As part of the Next Generation Patents (NGP) transition, the Canadian Patents Database (CPD) now contains a more detailed Event History, which replicates the Event Log of our new back-office solution.

Please note that "Inactive:" events refers to events no longer in use in our new back-office solution.

For a clearer understanding of the status of the application/patent presented on this page, the site Disclaimer , as well as the definitions for Patent , Event History , Maintenance Fee  and Payment History  should be consulted.

Event History

Description Date
Inactive: Adhoc Request Documented 1996-09-01
Time Limit for Reversal Expired 1996-03-02
Letter Sent 1995-09-01
Grant by Issuance 1992-09-01

Abandonment History

There is no abandonment history.

Owners on Record

Note: Records showing the ownership history in alphabetical order.

Current Owners on Record
None
Past Owners on Record
JOHN D. SCHEIBLE
JOHN G. SCHRIVER
WILLIAM L., JR. RIFFEL
Past Owners that do not appear in the "Owners on Record" listing will appear in other documentation within the application.
Documents

To view selected files, please enter reCAPTCHA code :



To view images, click a link in the Document Description column (Temporarily unavailable). To download the documents, select one or more checkboxes in the first column and then click the "Download Selected in PDF format (Zip Archive)" or the "Download Selected as Single PDF" button.

List of published and non-published patent-specific documents on the CPD .

If you have any difficulty accessing content, you can call the Client Service Centre at 1-866-997-1936 or send them an e-mail at CIPO Client Service Centre.


Document
Description 
Date
(yyyy-mm-dd) 
Number of pages   Size of Image (KB) 
Cover Page 1993-11-03 1 15
Drawings 1993-11-03 9 199
Abstract 1993-11-03 1 18
Claims 1993-11-03 2 35
Descriptions 1993-11-03 16 508
Representative drawing 2000-08-08 1 8
Fees 1994-06-22 2 108