U.S. patent application number 10/988789 was filed with the patent office on 2006-05-18 for frictionally engaged supplied air helmet face seal.
Invention is credited to Desmond T. Curran, Peter D. Lee, Richard D. Williams.
Application Number | 20060101552 10/988789 |
Document ID | / |
Family ID | 35841721 |
Filed Date | 2006-05-18 |
United States Patent
Application |
20060101552 |
Kind Code |
A1 |
Lee; Peter D. ; et
al. |
May 18, 2006 |
Frictionally engaged supplied air helmet face seal
Abstract
A supplied air helmet 10 that has a visor 14, and a face seal 12
that includes a frame member 16 and a sealing member 18. The frame
member 116 can be secured to the visor 14 by frictional engagement.
The use of frictional engagement as opposed to pegs, adhesives, and
hook and look type fasteners, may reduce the number of parts, may
permit face seal installation and/or removal in a less onerous
manner, and may reduce the opportunity for fastener failure.
Inventors: |
Lee; Peter D.; (Cleveland,
GB) ; Curran; Desmond T.; (County Durham, GB)
; Williams; Richard D.; (Lancaster, GB) |
Correspondence
Address: |
3M INNOVATIVE PROPERTIES COMPANY
PO BOX 33427
ST. PAUL
MN
55133-3427
US
|
Family ID: |
35841721 |
Appl. No.: |
10/988789 |
Filed: |
November 15, 2004 |
Current U.S.
Class: |
2/9 ;
2/171.3 |
Current CPC
Class: |
A62B 18/04 20130101;
A62B 18/082 20130101 |
Class at
Publication: |
002/009 ;
002/171.3 |
International
Class: |
A41D 13/00 20060101
A41D013/00 |
Claims
1. A supplied air helmet that comprises: (a) a visor; and (b) a
face seal that includes a frame member and a sealing member,
wherein the frame member is secured to the visor by frictional
engagement.
2. The supplied air helmet of claim 1, wherein the frictional
engagement occurs at first and second temporal locations.
3. The supplied air helmet of claim 2, wherein the frictional
engagement also occurs at a third location on the visor.
4. The supplied air helmet of claim 3, wherein the third location
is proximal to a wearer's forehead when the supplied air helmet is
worn.
5. The supplied air helmet of claim 1, further comprising a crown
member that is secured to the visor at first and second engagement
points.
6. The supplied air helmet of claim 2, wherein the frictional
engagement occurs at the first and second engagement points.
7. The supplied air helmet of claim 6, wherein first and second
spacer elements are disposed at the first and second engagement
points, the face seal being rotatable about the first and second
spacer elements.
8. The supplied air helmet of claim 1, wherein the frame member has
brow and chin portions that are offset from each other at an angle
.alpha. of 50 to 80 degrees.
9. The supplied air helmet of claim 1, wherein the sealing member
is elastically stretchable.
10. The supplied; air helmet of claim 9, further comprising a tab
for drawing a chin portion of the sealing member underneath the
wearer's chin when donning the supplied air helmet.
11. The supplied air helmet of claim 1, further comprising an air
duct and a crown member for supporting the air duct, the air duct
directing clean air into a breathing zone of the supplied air
helmet.
12. The supplied air helmet of claim 11, being adapted for
connection to a powered air purifying system.
13. The supplied air helmet of claim 11, being adapted for
connection to a self-contained breathing apparatus.
14. The supplied air helmet of claim 1, being a welding helmet.
15. A supplied air helmet that comprises: (a) a visor; and (b) a
face seal that includes a frame member and a sealing member, the
frame member being held in the visor by means that consists
essentially of configuration of the frame member and the visor such
that the frame member and visor are frictionally held together.
16. A supplied air helmet that comprises: (a) a visor; (b) a face
seal that includes a frame member and a sealing member; and (c) a
means for causing frictional engagement between the face seal and
the visor.
17. The supplied air helmet of claim 16, wherein the frame member
is adapted to conform in response to manual pressure and to return
to an original configuration once the manual pressure ceases.
Description
BACKGROUND
[0001] Supplied air helmets are regularly worn in environments
where the surrounding ambient air contains contaminants. These
helmets have a fluid impermeable visor that is pulled down in front
of the wearer's face. The visor has a window through which the
wearer can see the surrounding environment. A face seal is attached
to the visor to provide a breathing zone or interior gas space that
is separate from the ambient, exterior gas space. The interior gas
space is located in front of the wearer's face and is defined, for
the most part, by the face seal that is attached to the visor, the
visor body, and the wearer's face. U.S. Pat. Nos. 6,250,299,
6,016,805, 6,014,971, 4,462,399, and 4,280,491 disclose examples of
supplied air helmets that use face seals.
[0002] To furnish the wearer with a safe supply of air for
breathing, clean air is forced into the interior gas space from a
supply tank or from a powered air system that drives the ambient
air through a filter. The wearer breathes this clean air and
exhales it back into the breathing zone. This exhaled air, along
with excess clean air that is forced into the breathing zone exits
the interior gas space through openings in the face seal. The
positive pressure that generally occurs within the interior gas
space precludes contaminants from entering the interior gas space
through the openings. Welders often wear supplied air helmets as
protection from breathing contaminants that are generated during
welding procedures. Examples of welding helmets are shown in the
following patent documents: U.S. Pat. Nos. 6,557,174, 6,591,424,
6,185,739, 5,533,206, 5,191,468, 5,140,707, 4,875,235, 4,853,973,
4,774,723, 4,011,594 and Des. 398,421; and WO 00/59421 and WO
99/26502.
[0003] Known face seals typically have been secured to the helmet
by fasteners such as pegs, clips, adhesive tape, and hook and loop
type devices. The use of such fasteners has required additional
equipment that must be provided on the supplied air helmet or the
face seal frame. In addition, when the face seal is secured to the
supplied air helmet through use of pegs, these pegs must be
disengaged from the face seal during its installation and
replacement. Because a crown support member (for supporting the
helmet on the wearer's head) typically also has been secured to the
helmet through the same pegs, it has been a cumbersome process to
replace the face seal. The use of adhesive tape and hook and loop
type fasteners can be onerous as well, and they have provided
locations for dirt and contaminants to accumulate, which
accumulation can cause the fastener to cease functioning. Hook and
loop type fasteners also tend to "peel-off" the helmet after
repeated use in response to repeated tugging on the hook and loop
material. Heat, for example, in a welding environment, also can
cause the adhesive to soften, which softening may cause
delamination of the fastener. Examples of supplied air helmets that
use various methods for securing a face seal to a helmet are shown
in U.S. Pat. Nos. 6,250,299 B1 and 6,014,971 to Danisch et al.
(adhesive or mechanical attachment), U.S. Pat. No. 6,016,805 to
Burns et al. (pegs or protrusions that mate with holes or use an
adhesive), U.S. Pat. No. 5,054,479 to Yelland et al. (adhesive),
and U.S. Pat. No. 4,280,491 to Berg et al. (adhesive).
SUMMARY OF THE INVENTION
[0004] The present invention involves a new manner of securing a
face seal to a supplied air helmet. In brief summary, the present
invention provides a supplied air helmet that comprises a visor and
a face seal where the face seal includes a frame member and a
sealing member and where the frame member is secured to the visor
by frictional engagement.
[0005] The present invention differs from known supplied air
helmets in that the face seal is secured to the supplied air helmet
using frictional engagement rather than fasteners such as pegs,
clips, and hook and loop materials. Because the present invention
uses this new method of engagement, the use of separate fastening
elements is avoided. Thus, less parts are needed to manufacture the
final product, which can save on manufacturing costs. Further,
installation and removal of the face seal may be achieved in less
onerous manner. There also is less opportunity for failure over
time, and the surface area onto which contaminants and dirt may
accumulate is substantially less.
[0006] These and other advantages of the invention are more fully
shown and described in the drawings and detailed description of
this invention, where like reference numerals are used to represent
similar parts. It is to be understood, however, that the drawings
and description are for illustration purposes only and should not
be read in a manner that would unduly limit the scope of this
invention.
GLOSSARY
[0007] In this document, the terms set forth below will have the
meanings as defined:
[0008] "breathing zone" means an interior gas space or a portion of
the interior gas space where oxygen is inhaled by a wearer of a
supplied air helmet;
[0009] "clean air" means air that has been filtered or that has
otherwise been made safe to breathe;
[0010] "elastic" means the ability of a strained material (e.g.,
the sealing member or the yarns that comprise the sealing member)
to substantially recover its original size and shape immediately
after being stressed to about twice its original length.
[0011] "exterior gas space" means the ambient atmospheric gas space
that surrounds the exterior of a supplied air helmet when worn on a
person;
[0012] "face" means the area on the front of a person's head,
defined mainly by the cheeks and temporal area (or side portions of
the facial regions), chin, forehead, and facial area located
therebetween;
[0013] "face seal" means a structure that contacts a person's face
and/or neck and/or other portions of the head to help separate an
interior gas space of a supplied air helmet from an exterior gas
space;
[0014] "filtered air" means air that has been passed through a
filter material to reduce the amount of any contaminants that may
have been present in the air before it was filtered;
[0015] "frame member" means a structural part(s) that plays a role
in supporting a sealing member;
[0016] "frictionally" means essentially through use of
friction;
[0017] "frictional engagement" means that the engagement occurs as
a result of friction between the two parts intending to be joined
without need for additional fastening from elements such as pins,
pegs, clips, and/or hook and loop materials;
[0018] "helmet" means a device that is worn on a person's head for
safety and/or protection purposes;
[0019] "interior gas space" means the space that exists between a
visor, a face seal, and a person's face when a supplied air helmet
is being worn;
[0020] "sealing member" means a structure or combination of parts
that may be solid and/or porous and that conformably contacts at
least a portion of a person's face to assist in defining a
separation between an interior gas space and an exterior gas
space;
[0021] "supplied air helmet" means a helmet that receives a supply
of clean air for a wearer of the device to breathe;
[0022] "visor" means a structure that is located in front of a
person's face when worn and that has a window to allow the person
to see through it; and
[0023] "welding helmet" means a helmet that has a darkened or
darkening window.
BRIEF DESCRIPTION OF THE DRAWINGS
[0024] FIG. 1 shows a rear perspective view of a supplied air
helmet 10 in accordance with the present invention;
[0025] FIG. 2 shows a rear perspective view of a supplied air
helmet 10, in accordance with the present invention, with the face
seal 12 being disengaged from the visor 14;
[0026] FIG. 3 shows a left side view of a supplied air helmet 10,
in accordance with the present invention, with the frame member 16
of the face seal 12 being shown in phantom lines; and
[0027] FIG. 4 illustrates a supplied air helmet 10, in accordance
with the present invention, which helmet 10 has an air duct 60 for
supplying clean air to the interior gas space of the helmet 10.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0028] In describing preferred embodiments of the invention,
specific terminology is used for the sake of clarity. The
invention, however, is not intended to be limited to the specific
terms so selected, and it is to be understood that each term so
selected includes all technical equivalents that operate
similarly.
[0029] In the practice of the present invention, a new face seal is
provided that can be frictionally secured to a visor of a supplied
air helmet at multiple locations. The frictional securement enables
less parts be used in the manufacture of the supplied air helmet
and, as opposed to a commonly-used hook and loop fastening means,
can provide a cleaner, more durable, and simpler form of
engagement.
[0030] FIG. 1 illustrates a supplied air helmet 10 that includes a
face seal 12 and a visor 14. The face seal 12 has a frame member 16
and a sealing member 18. A window or lens 20 is provided on visor
14 so that a wearer of the helmet 10 can see in the forward
direction. If the helmet is used for welding purposes, the window
can be an auto-darkening lens (ADL) that darkens immediately in
response to light from a welder's torch, (see, for example, U.S.
Pat. Nos. 6,097,451 and 5,825,441, issued to Homell and Palmer). A
head harness or crown member 22 may be attached to the visor 14 at
first and second locations 24 and 26. The crown member 22 allows
the supplied air helmet 10 to be comfortably supported on a
wearer's head. An example of a crown member is shown in U.S. Pat.
Nos. 5,481,763 and 5,394,568 to Brostrom et al. Threaded members 28
and 30 may be provided at first and second locations of hinged
assemblies 24 and 26, respectively, to secure the crown member 22
to the visor 14. First and second spacer elements or washers 32 and
34 may be used to provide sufficient spacing between the visor 14
and the crown member 22 and to allow the crown member 22 to rotate
easily relative to the visor 14. The rotational movement of the
visor 14 can enable it to be temporarily lifted above a wearer's
face when not in use. The hinged assembly at locations 24 and 26
allows the wearer to rotate the visor or face shield 14 away from
the wearer's face during periods of non-use and to rotate it
downwardly over the face when working. The hinged assembly may be
designed so that the visor 14 can be temporarily fixed at different
incremental positions between uppermost in lowermost positions, or
it may be freely movable between these positions. Alternatively,
the visor 10 may be fixed so that it does not rotate with respect
to the crown member 22.
[0031] As shown in FIGS. 1 and 2, the first and second spacer
elements 32 and 34 also provide a guide means for placing the face
seal 12 in proper location for frictional engagement with the visor
14. The guide means also could be provided by the visor contour
itself, by grooves or ribs in the visor, or by protrusions and/or
detents, or a combination of such features. The face seal frame
member 16, thus, frictionally contacts the visor 14 at first and
second temporal locations 24 and 26. A third location 36 (proximal
to a wearer's forehead when worn) for frictional engagement between
the frame member 16 and the visor 14 may also be provided to
preclude rotational movement of the face seal 12 relative to the
helmet 10 and to ensure that the face seal 12 is adequately secured
to the visor 14. Additional locations for friction engagement
between face seal 12 also may be provided as desired. A head top or
hard hat may also be furnished to the helmet 10 as a means for
protecting the head or skull of the wearer. An example of the head
top/face shield combination is shown in U.S. Pat. No. 6,016,805 to
Burns et al.--see also International Patent Publication WO
99/26502.
[0032] FIGS. 2 and 3 further illustrate how the face seal 12 can be
secured to the visor 14. The frame member 16 may be flexible or
conformable to allow for its frictional placement within the more
rigid visor. The frame member 16 has first and second side portions
38 and 40 that can be pushed centrally inward or towards each other
so that they can be squeezed between respective first and second
visor side portions 42 and 44. The frame member 16 thus may be
adapted to conform in response to manual pressure and to return
towards an original configuration when that pressure ceases. The
frame member 16 also is provided with first and second receptacles
46 and 48, respectively, that are fashioned to rotatably reside
against the spacer elements 32 and 34 at locations 24 and 26. The
spacer elements 32 and 34 act as pivot points at first and second
temporal locations 24 and 26. Once the frame member 16 is placed
within the helmet 10 such that receptacles 46 and 48 are juxtaposed
against the hinge assembly at locations 24 and 26, the frame
assembly 16 may be rotated clockwise as shown in FIG. 3. This
clockwise rotation continues until the front portion 50 of the
frame member 16 engages the third engagement point 36 or shelf 52.
When the front portion 50 of the frame member 16 is juxtaposed upon
shelf 52, further rotational movement is prohibited and the face
seal 12 remains essentially statically held within the face shield
14. Although the drawings illustrate three frictional engagement
points, the invention contemplates the use of further engagement
points (e.g., 4, 5, 6 or more) if necessary or desirable.
[0033] As shown in FIG. 3, the frame member 16 has brow and chin
portions 53 and 55, respectively. These portions may be rigidly and
integrally joined together and preferably define an included angle
.alpha. that is less than 90.degree.. Preferably, the angle .alpha.
is less than about 50 to 80 degrees. Use of a frame member that has
such an angle .alpha. can allow a good fit to be achieved for
prohibiting contaminant entry into the interior gas space.
[0034] An understanding of how to wear the supplied air helmet 10
can be gathered from FIGS. 1 and 2. To don the helmet 10, the
wearer places the crown member 12 on their cranium and rotates the
visor 14 downwardly such that it resides directly in front of the
wearer's face. The wearer then pulls on tab 52 to draw the chin
portion 54 of sealing member 18 underneath their chin. The
remainder of the periphery 56 of the sealing member 18 draws
tightly against the forehead, cheeks, and temporal area of the
wearer. The periphery 56 of sealing member 18 defines an opening 57
that is elastically stretchable and is sized to be smaller than the
typical wearer's face to enable the face seal to fit snugly against
faces of various sizes. A breathing zone or interior gas space is
thus created, defined by the face of the wearer, the sealing member
18, and the face shield or visor 14. Pores are generally provided
in the sealing member 18 to allow air to escape from the interior
gas space. Despite the generally porous nature of the sealing
member 18, contaminants are generally precluded from entering the
interior gas space because of the positive pressure that generally
exists within it.
[0035] In operation, air is supplied to the interior gas space
under pressure from a powered air supply source. Examples of these
types of devices are shown in U.S. Pat. Nos. 6,279,572B1,
6,250,299B1, 6,014,971, 5,125,402, 4,965,887, 4,462,399, and
4,280,491. The air may be channeled into the interior gas space via
an air duct that is in fluid communication with the powered air
supply source (not shown). When using a powered air supply source,
the ambient air is powered or forced through an air filter before
being directed into the interior gas space. Examples of blowers
that may be used in connection with a supplied air system for
directing clean air into the interior gas space are shown in U.S.
Pat. Nos. 6,575,165B1 and D449,099S. A flow sensor may be used on
the supplied air helmet to provide an indication of when air flow
into the breathing zone falls below a safe level--see U.S. Pat. No.
6,615,828 B1 to Petherbridge. In addition, a non-volatile memory
device may be attached to the filter element to keep a record of
the filter element's usage--see U.S. Pat. No. 6,186,140 B1 to
Hogue.
[0036] FIG. 4 illustrates an example of an air duct 60 that could
be used to direct air into the interior gas space of the helmet 10.
This air duct 60 is also shown in U.S. patent application Ser. No.
29/202,969, filed on Apr. 7, 2004 and entitled Air Duct, now U.S.
Pat. No. ______ to Hind et al. The air duct 60 has an air inlet 62
and an air outlet 64 and is supported by the crown member 22. The
inlet 62 is connected to the clean air source, and the outlet 64 is
disposed between the sealing member 18 and the wearer's forehead
(not shown). As indicated, air flow exits the interior gas space
through, for example, pores that may be present in the sealing
member 18 (FIGS. 1 and 2). The air duct 60 can be fixed to the
crown member 22 in two places. The rear of the air duct 60 can be
held a fixed distance from the back of the head harness 22 by a
stamped out plastic part 66. The front of the air duct 60 can be
stapled to the front of the head harness 22 at the brow. In this
way, the air duct 60 is prevented from moving or wobbling when in
use. At the brow, the air duct 60 passes between the face seal 12
and the head harness 22. An elastomeric face seal material can
allow the face seal to form a good seal around the air duct. An
adjustment knob 67 can be provided on the crown member so that its
tension can be altered to fit various head sizes.
[0037] The sealing member can take the form of a knitted fabric
that comprises, for example, a blend of acrylic and cotton. The
fabric may be elastomeric or may include elastomeric yam to improve
stretchability. The fabric also can be fashioned to be inherently
flame retardant, which may be important for welding and grinding
applications. The fabric can be essentially any color and can be
made from materials such as polyester, modified acrylic, or a
mixture or blend of these polymeric materials. With respect to its
thickness, the fabric may have a thickness of a single fifties
count yam, although other thicknesses may be suitably used. What is
important is that the face seal is comfortable to wear and that it
allows exhausted air to be rapidly purged from the interior gas
space. A knitted fabric that contains elastic yam and has a fold
where the periphery of the seal member makes predominant contact
with the wearer's face has been found to be particularly
comfortable. The knitted fabric may be secured to a frame member
made of, for example, a 1 mm thick polypropylene plastic. The frame
member desirably has a matted surface on at least one side to avoid
reflection that could interfere with the user's vision. In general,
the plastic frame may be about 0.4 mm to 3 mm thick and can be
structured such that it is not overly flimsy and such that it
retains its intended shape when not being subjected to manual
forces or pressure.
[0038] An example of a face seal that has a porous knitted sealing
member is described in more detail in U.S. patent application Ser.
No. __/______, entitled Supplied Air Helmet Having Knitted Face
Seal, filed on Nov. 12, 2004 under attorney docket number
60019US002. The face seal may have a differentiated permeability
design to improve airflow through the breathing zone--see U.S.
patent application Ser. No. __/______, entitled Supplied Air Helmet
Having A Face Seal With Differentiated Permeability, filed on Nov.
12, 2004 under attorney docket number 60020US002. Another example
of a face seal is shown in U.S. Pat. No. 6,016,805 to Burns et
al.
[0039] In addition to the supplied air systems mentioned above, the
present invention also could be used in conjunction with a
compressed air system such as a self-contained breathing apparatus
(SCBA) that has a tank of air or oxygen, typically under pressure,
for supplying clean air to a person. Examples of SCBA systems are
shown in the following U.S. Pat. Nos.: 6,478,025, 4,886,056,
4,586,500, and 4,437,460. For purposes of construing this
invention, a SCBA system is considered to be a supplied air system.
Further, the inventive supplied air systems may be used not only in
conjunction with welding helmets or welding environments but may
also be used, for example, in helmets fashioned for surgical
environments and clean air rooms--see, for example, U.S. Pat. Nos.
4,901,716, 4,055,173, 4,019,508, and 3,955,570.
[0040] This invention may take on various modifications and
alterations without departing from the spirit and scope thereof.
Accordingly, it is to be understood that this invention is not to
be limited to the above-described, but it is to be controlled by
the limitations set forth in the following claims and any
equivalents thereof.
[0041] It is also to be understood that this invention may be
suitably practiced in the absence of any element not specifically
disclosed herein.
[0042] All patents and patent applications cited above, including
those in the Background section, are incorporated by reference into
this document in total.
* * * * *