[0001] This invention relates to a facemask or respirator which incorporates a transparent
visor compatible with helmet mounted electro-optical sighting devices such as, for
example, night vision goggles (NVG). The facemask of the present invention is however
not exclusively designed for use with NVG's but can be used with other helmet mounted
devices. The facemask of the invention is particularly suitable for use by aircrew
but it can also be incorporated into a respirator worn by other persons such as firefighters.
[0002] Some helmet mounted electro-optical sighting devices project their images onto a
visor located in front of the wearer's eyes. To work satisfactorily, the distance
between the exit lens of the NVG's and the wearer's eyes (known as eye relief) is
critical if the images are to be in focus, and clearly visible with the optimum field
of view to the wearer. Some facemasks currently available have the visor formed as
part of the rigid exo shell in which the flexible oro-nasal mask which covers the
wearer's nose and mouth is mounted. Oxygen is supplied to the wearer through this
flexible mask. A rubber nuclear, biological and chemical (NBC) hood can be attached
to the top and sides of the visor as well as to the periphery of the rigid front shell
to enclose the wearer's head. A problem with this prior art respirator is that the
eye relief dimension is neither fixed nor adjustable. For instance, if the wearer
has a pronounced forwardly extending chin, the bottom of the oxygen mask and thus
the rigid shell and the visor extending upwardly from it will be inclined at a lesser
angle to the wearer's eyes than it would be if he has a receding chin. Thus, with
a protruding chin, the top of the visor will be tilted closer to the wearer's eyes
whereas with a receding chin, it will be tilted further away from them.
[0003] In order to overcome this problem, a separate visor has been used which is attached
to the NBC hood along its top, side and bottom edges, the hood extending over the
rigid exo-shell to enclose it completely. The problems with these mechanisms are:
a) the eye relief distance is random determined by the NVG;
b) after initial positioning during dressing, the visor can move thereafter, (for
instance, if worn by aircrew in flight when subjected to high G forces) so it may
end up being too far away from the wearer's eyes to permit the proper use of electro-optical
devices. For NVG's to work properly, the preferred eye relief distance should be between
15mm and 30mm.
[0004] It is therefore an object of the present invention to provide a facemask or respirator
including a visor which overcomes these problems.
[0005] According to the invention, there is provided a facemask incorporating breathing
equipment comprising an outer body to enclose the wearer's nose and mouth, a flexible
oro-nasal oxygen mask mounted inside said outer body whose periphery makes a seal
with the wearer's face, said flexible mask having an inspiratory and expiratory valve
therein and a visor mounted on the body in the line of sight of the wearer by a pivot
mechanism which allows the angular position of the visor relative to the outer body
to be adjusted and retained in its selected angular position relative to the wearer's
face.
[0006] Preferably the pivot mechanism includes a ratchet system which allows the visor to
be incrementally moved to various different angular positions and retained therein.
The pivot mechanism can also be mounted on adjustment means which also permit linear
movement thereof towards or away from the wearer's face.
[0007] In the preferred embodiment, the body is a rigid shell which has a lateral extension
on each side thereof on which the pivot mechanism is mounted. Each lateral extension
can take the form of a wing integrally moulded with the rigid shell or alternatively
it can be a tubular bar. The visor is pivotally attached to these lateral extensions.
[0008] In the preferred embodiment, the bottom of the visor has a pair of legs extending
therefrom for attachment to the pivot mechanism. In one embodiment an adjustment handle
is mounted on said legs and extends forwardly therefrom, the handle being engagable
by the wearer's hand to pivot the visor. Alternatively, a handle can be attached to
the top of the visor so that the wearer can pull the visor into a different position.
[0009] If necessary, a flexible NBC hood can be attached to the periphery of the visor to
extend over the wearer's head and includes a front portion which encloses the rigid
body and visor pivot mechanism.
[0010] Embodiments of the invention will now be described, by way of example only, with
reference to the accompanying drawings, in which:
Figure 1 is a side view of one form of facemask of the present invention in position
on a wearer's head and connected to his helmet;
Figure 2 is a front view of one means for mounting the visor on the rigid shell shown
in Figure 1;
Figure 3 is a side view of the arrangement shown in Figure 2;
Figure 4 is another way of mounting the visor on the rigid shell;
Figure 5 is a still further way of mounting the visor on the shell;
Figure 6 is a perspective view of the visor shown in Figure 5;
Figure 7 is a schematic view showing the facemask of Figure 1 but including an NBC
hood;
Figure 8 is a front view of the facemask and hood shown in Figure 7;
Figure 9 is a schematic view of an alternative facemask and hood assembly;
Figure 10 is a front view of the hood and facemask assembly shown in Figure 9.
Figure 11 is a schematic view of another facemask assembly of the invention;
Figure 12 is a view of a facemask of the invention incorporated into a full face respirator;
Figure 13 is a schematic cross section of the respirator shown in Figure 12; and
Figure 14 is a view of an alternative form of respirator.
[0011] Referring now to the drawings, Figure 1 shows a pilot 1 wearing a rigid protective
helmet 2. A flexible oro-nasal face-piece 3, usually made of a natural or synthetic
rubber material, surrounds the wearer's nose and mouth and is mounted in a rigid plastic
shell 4 attached to the helmet 2 by means of a harness arrangement 5 having a fitting
6 at one end to releasably attach it to a corresponding fitting part 7 mounted on
the helmet. The harness 5 includes adjustable means (not shown) so that its length
can readily be changed to ensure that the face-piece 3 rests comfortably on the wearer's
face with its edge lip 14 making a seal with the area of the wearer's face surrounding
his nose and mouth. An oxygen supply 10 is connected to the rigid shell 4 in known
manner.
[0012] A transparent visor 8 is connected to the rigid shell 4 by a pivot mechanism 9 and
extends upwardly from the shell into the wearer's line of sight. An electro-optical
sighting device 13 such as a pair of night vision goggles (NVG) is mounted on arm
12 attached by means 17 to the helmet, the electro-optical sighting device 13 being
mounted in front of the visor 8 but in line with the wearer's eyes 16. The electro-optical
sighting device projects an image through the visor 8 in known manner so no further
description thereof will be given here. The eye relief dimension is the distance X
between the wearer's eye 16 and the exit lens of the NVG 13. When properly adjusted
and, during flight, the visor should not touch the exit lens of the NVG.
[0013] Figures 2-5 show by way of example two different ways in which the visor 8 can be
mounted on the rigid shell 4. Figures 2 and 3 show the assembly of Figure 1 wherein
visor 8 is pivotally mounted by suitable means 9 to the rigid shell 4 and has a handle
15 attached to its upper region which the pilot can grip to move the visor either
forwardly in the direction of arrow A or rearwardly in the direction of arrow B. Val
Salva holes 11 are provided in the rigid shell 4 allowing the pilot access to pinch
his nose during descent to equalise the pressure in his ears with that of the ambient
pressure in the cockpit.
[0014] Referring now to Figures 2 and 3, one preferred form of mounting the visor 8 on the
rigid shell 4 is shown which comprises lateral extensions or wings 20 extending from
opposite sides of the shell 4, and moulded integrally therewith. Each wing includes
means 9 thereon which cooperate with corresponding means on legs 23 of the visor 8
whereby a hinge pin can be inserted through said co-operating parts to hingedly attach
the visor 8 to the rigid shell 4. In order to be able to incrementally change the
position of the visor 8 relative to the rigid shell 4, and retain it in a selected
position, the hinge means preferably includes a ratchet mechanism of known type (not
shown).
[0015] Referring now to the embodiment shown in Figures 4-6, it can be seen that it differs
from the embodiment of figures shown in Figures 2 and 3 in that the lateral extensions
comprise tubular rods 21 extending from each side of the upper part of the rigid shell
4. The visor 8 has a centrally located cut-out section 18 which fits over the top
end of rigid shell 4 and the bottom parts or legs 23 of the visor on either side of
said cut-out 18 are pivotally attached to the laterally extending rods 21 by a hinge
mechanism 9 which also preferably includes a ratchet system. As a result, the visor
8 can be pivoted in the direction A or B relative to the coaxially aligned laterally
extending rods 21 when the pilot pulls on the handle 15 at the top of the visor or
alternatively pushes it.
[0016] Figures 5 and 6 show an alternative arrangement wherein the pair of downwardly extending
legs 23 on the visor 8 which extend below pivot axis 26 have a U-shaped handle 25
connected thereto by means of feet 24 as illustrated. It can be seen therefore that
if the pilot pulls on the handle 25 in the direction of arrow A, the top of the visor
will move in the direction of arrow B to move it closer to the wearer's face. Similarly,
if the pilot pushes on the handle in the direction of arrow B, the top of the visor
8 will move away from the wearer's face in the direction of arrow A.
[0017] Figures 7 and 8 show the embodiments of Figures 1-6 but with an NBC cowl 30 having
a neck portion 31 attached to the visor 8. The cowl 30 is sealed to the visor around
its periphery 32. The front of the cowl 30 in the region of the rigid shell 4 has
an extension 33 having a hole 34 formed therein. The perimeter of the hole 34 is sealingly
attached to the rigid shell 4. The attachment harness 5 is also mounted on the rigid
shell 4.
[0018] A handle 15 is attached to the top of the visor 8 and it will be appreciated that
when the pilot pulls on this handle, the visor can move forwardly in the direction
of arrow A away from the wearer's head or inwardly in the direction of arrow B towards
the wearer's head when the pilot pushes on the handle 15. This movement is allowed
and accommodated for by the resilience in the material of the cowl 30 which is normally
made of neoprene or natural rubber.
[0019] The embodiment shown in Figures 9 and 10 is the embodiment of Figures 5 and 6 but
with an NBC cowl 30 having a neck portion 31 attached to the visor 8. As can be seen
from the drawing, the cowl 30 is sealed to the visor 8 around its periphery at 32.
The cowl has a front section 33 which encloses a substantial part of the rigid shell
4, the section 33 having an aperture 34 therein which is sealingly attached to the
front portion of the rigid shell 4 allowing the front portion thereof to protrude
through to which the oxygen hose 10 is connected. The upper part of the U-shaped handle
25 protrudes through an NBC seal 37 in the front section 33 of the cowl. As with the
embodiment of Figures 7 and 8, if the pilot pulls on the handle 25 in the direction
of arrow A, the visor 8 will pivot about the pivot axis 9 and will move towards the
wearer's eyes 16. If the pilot pushes on the handle 25 in the direction of arrow B,
the top of the visor 8 will move away from the wearer's eyes 16.
[0020] Figure 11 shows a similar design of facemask to that shown in Figures 9 and 10 except
that the rigid shell 4 on which the visor 8 is pivotally mounted at 9 is totally enclosed
within front extension 33 of the NBC hood.
[0021] As with the Figures 9 and 10 embodiment, an inverted U-shaped handle 25a is attached
by portions 24 to legs 23 extending downwardly from each side of the visor 8 in the
same manner as shown in Figure 6.
[0022] The NBC hood 30 is attached to the periphery of the visor 8 at 32 in the same manner
as that shown in Figure 10. However, the front portion 33 completely encloses the
oro-nasal rigid shell 4 and the handle 25a. The front section 33 is made from a thin
flexible rubber material so the wearer can easily feel the location of the handle
25 within it. Thus, if he pulls on the handle 25a in the direction of arrow A, the
top of the visor 8 connected thereto will move towards his eyes 16 and vice versa.
[0023] The advantage of this design over that shown in Figures 9 and 10 is that as the handle
25a is totally enclosed within the front portion 33 of the hood 30 so there is nothing
to impair the wearer's downward vision. Also, the need for the NBC seals 37 is avoided.
[0024] Turning now to Figures 12 and 13, there is shown a facemask of the invention incorporated
into a full face respirator for use, for instance, by a firefighter. As firefighters
are now using helmet mounted electro-optical devices such as NVG's to help them see
in smoke filled environments, they need the position of the visor 48 to be adjustable
to ensure the correct eye relief dimension so that the wearer can focus on the projected
image.
[0025] The facemask comprises a moulded rubber body 41 having a front portion 42 to the
end of which an outlet 43 for exhaled air is mounted in known manner. An inlet 44
for air/oxygen is provided on either side of the rubber body 41, each inlet being
closed by a one-way flap valve of known type. Each inlet 44 has means on it such as
a screwthread or bayonet fitting (not shown) to allow a supply hose to be attached
to it.
[0026] Peripheral edge 46 of the body is formed with a flexible return 46a which cooperates
with and seats on the wearer's face when the facemask is fitted thereto. Tabs 47a,
b, c are moulded on the facemask and include attachment means for releasably securing
straps 49a, b, c thereto, the straps fitting over the wearer's head to retain the
facemask 41 on the wearer's face with the return 46a making an airtight seal therewith.
[0027] A rigid or flexible oro-nasal mask 40 of known type is mounted within the facemask
41 and includes an outlet therefrom (not shown) which communicates with the outlet
43 and also includes a known one-way valve which only permits the passage of exhaled
air therethrough. A pair of inlet valves 45 are provided on each side of the oro-nasal
mask 40, each inlet being closed by a known one-way flap valve which only allows breathable
air/oxygen mixture supplied to the interior of the facemask 41 via the inlets 44 to
reach the interior of the oro-nasal mask 40.
[0028] A full face transparent visor 48 is mounted in a two part rigid frame 39a,39b clamped
together by means such as bolts 38 on either side of the visor. It should be noted
that the peripheral region of the facemask body 41 around the visor 48 includes an
expandable or extendable bellows section 50 for reasons to be explained hereafter.
[0029] The mid section of the bottom of the frame 39a,39b is mounted on a pivot mechanism
which includes a pivot pin 9. Thus, the visor 48 can rotate about pivot pin 9 and
the top of the visor can be moved towards or away from the wearer's eyes along arc
A-B. Preferably, the pivot mechanism includes a ratchet system allowing the visor
to be pivoted incrementally about pivot 9 and then retained in the selected angular
position.
[0030] The pivot mechanism including pivot pin 9 is preferably also mounted on an adjustment
mechanism 51 which allows the pivot 9 to be moved in linear direction X-Y either away
from or towards the wearer's face. This adjustment mechanism 51 preferably also incorporates
a ratchet mechanism to allow incremental linear movements to be made, the pivot pin
9 then being retained in the selected position.
[0031] It will be appreciated that any movement of the frame 39a,39b and visor 48 relative
to the wearer's face to adjustment for eye relief will be accommodated by the bellows
section 50 around the visor 48 on the body 41.
[0032] Figure 14 shows an alternative arrangement to that shown in Figures 12 and 13 in
which the visor adjustment mechanism is located inside the facemask rather than externally.
[0033] In this arrangement, the same reference numerals will be used for the same or similar
parts to those shown in the earlier Figures.
[0034] In the illustrated embodiment, the visor 48 is sealingly mounted in a rigid frame
39. The bottom of the frame 39 has attached to its internal surface a fixture 51 as
illustrated which rotates about pivot 9. The pivot 9 is mounted on an assembly (not
shown) which is attached to the facemask so that the pivot 9 can move in a linear
direction towards or away from the wearer's face in the direction of arrows X-Y. The
assembly mounting pivot 9 is preferably mounted on a ratchet mechanism so that it
can be incrementally moved in the direction of arrows X-Y and retained in the selected
position.
[0035] The front of the fixture 51 includes a section 52 which protrudes upwardly through
an aperture 54 in the front portion 42 of the facemask body 41. A flexible rubber
section 43a is connected to the front portion 42 and extends over the section 52 to
enclose it, this flexible section being connected to the frame 39 via a bellows section
50 which extends around the whole of the periphery of the visor 48 and forms part
of the body 41.
[0036] With the illustrated arrangement, the wearer of the facemask can readily adjust the
angle of inclination of the visor 48 relative to the wearer's face by pushing or pulling
on the section 52 thereby causing the fixture 51 to rotate about pivot 9 whereby the
visor moves in the direction of arrows A-B. By applying a linear pressure to the base
of the frame 39, the pivot point 9 can be moved in a linear manner in the direction
of arrows X-Y relative to the wearer's face on its ratchet mounting (not shown) and
then retained in its selected position.
[0037] In yet another embodiment (not illustrated), the section 52 and the part of the fixture
51 connecting it to the pivot 9 can be omitted. With this embodiment, the wearer can
pivot the top of the visor 48 relative to his or her face in the direction of arrows
A-B by pushing or pulling on the top of the visor. By pushing on the base of the frame
39, the pivot 9 can be moved in a linear manner in the direction of arrows X-Y to
change the location of the pivot 9 relative to the wearer's face.
[0038] It will be appreciated that the pivot 9 in the embodiments of Figures 1-11 can also
be mounted on a mechanism which allows it to be moved in a linear direction towards
or away from the wearer's face. The mounting mechanism can also include a ratchet
system to retain the pivot 9 in its selected position.
[0039] The facemask of the invention allows the orientation of the visor 48 relative to
the wearer's face and eyes 16 to be infinitely adjusted to suit the wearer's eye relief
dimension thereby ensuring optimum performance.
1. A facemask incorporating breathing equipment comprising an outer body to enclose the
wearer's nose and mouth, a flexible oro-nasal oxygen mask mounted inside said outer
body whose periphery makes a seal with the wearer's face, said flexible mask having
an inspiratory and expiratory valve therein, and a visor mounted on the body in the
line of sight of the wearer, by a pivot mechanism which allows the angular position
of the visor relative to the outer body to be adjusted and retained in its selected
angular position relative to the wearer's face.
2. A facemask as claimed in claim 1 wherein the pivot mechanism includes a ratchet system
which allows the visor to be incrementally moved to various different angular positions
and retained therein.
3. A facemask as claimed in claim 1 or claim 2 wherein the outer body is a rigid shell
which has a lateral extension on each side thereof on which the pivot mechanism is
mounted.
4. A facemask as claimed in claim 3 wherein each lateral extension is a wing.
5. A facemask as claimed in claim 4 wherein each wing is moulded integrally with the
rigid shell.
6. A facemask as claimed in claim 3 wherein each lateral extension is a tubular bar.
7. A facemask as claimed in any of claims 3-6 wherein the visor is pivotally attached
to said lateral extensions.
8. A facemask as claimed in claim 7 wherein the bottom of the visor is pivotally attached
to said lateral extensions.
9. A facemask as claimed in claim 7 wherein the bottom of the visor has a pair of legs
extending therefrom.
10. A facemask as claimed in claim 9 wherein an adjustment handle is mounted on said legs
and extends forwardly therefrom.
11. A facemask as claimed in any preceding claim wherein a handle is attached to the top
of the visor.
12. A facemask as claimed in any preceding claim wherein a flexible NBC hood is attached
to the periphery of the visor and extends over the wearer's head and includes a front
portion which encloses the rigid shell and pivot mechanism for the visor.
13. A facemask as claimed in claim 1 wherein the body is moulded from a flexible material
and the visor is full face and mounted in a frame.
14. A facemask as claimed in claim 13 wherein the periphery of the moulded body adjacent
the frame includes an extendable portion.
15. A facemask as claimed in claim 14 wherein the extendable portion is moulded as bellows.
16. A facemask as claimed in any preceding claim wherein the pivot mechanism is mounted
on adjustment means which allow linear fore-aft movement of the pivot mechanism relative
to the wearer's face.
17. A facemask as claimed in claim 16 wherein the adjustment means includes a ratchet
mechanism.