Note: Descriptions are shown in the official language in which they were submitted.
CA 02665891 2009-05-12
ADJUSTABLE SOUND VALVE
The present application relates generally to a hearing protection device, and
particularly,
to a hearing protection device with adjustable sound attenuation.
BACKGROUND OF THE INVENTION
Individuals in certain environments, such as industrial settings, may be
exposed to
high levels of environmental noise, which can lead to permanent hearing
damage. The use
of hearing protection devices such as ear-muffs or earplugs can significantly
attenuate
environmental noise and reduce or prevent hearing damage. In some cases, ear-
muffs are a
preferred form of hearing protection device because they typically attenuate
sound more
than earplugs, they can easily be handled by an individual wearing gloves, and
they
insulate the ears from cold.
In some cases, individuals may remove their ear-muffs to communicate,
resulting
in exposure to the full intensity of environmental noise. In other cases,
individuals may not
use their hearing protection because environmental noise is intermittent. When
environmental noise does occur, those individuals are sometimes left without
hearing
protection, or are unable to prevent temporary exposure as they apply their
ear-muffs.
Accordingly, there is a need for a hearing protection device that allows the
wearer
to easily control the degree of sound attenuation while it is being worn.
SUMMARY OF THE INVENTION
There is provided an adjustable sound valve comprising: a passage for sound
having a passage size; an attenuator for varying the passage size; and a
controller for
controlling the attenuator. The controller is configurable between a first
position in which
the passage size is pre-determined, and a second position in which the passage
size is
variable based on the attenuator.
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The attenuator has a gasket base and a plug. The gasket base has a first
gasket base
opening and a second gasket base opening. The plug cooperates with the second
gasket
base opening to define the passage size of the passage for sound, which is
defined by the
distance between the second gasket base opening and the plug. The controller
has a dial
for varying the passage size.
The controller has a shaft, a gasket barrier, and a spring that engages the
gasket
barrier and the dial. The shaft has a dial end and a plug end, a longitudinal
axis, and a shaft
pin extending away from the longitudinal axis of the shaft. The gasket barrier
is mounted
over the first gasket base opening to create a seal, and has a gasket barrier
shaft hole for
receiving the shaft, a gasket barrier hole for allowing the transmission of
sound, and a cam
mounted to the gasket barrier. The cam has a rising cam surface for engaging
the shaft pin,
and a cam stop that prevents further travel of the shaft pin along the rising
cam surface.
The shaft is rotatably mounted through the gasket barrier and the gasket base,
and
connected to dial at the dial end, and connected to the plug at the plug end.
The spring is in
compression and urges the dial away from the gasket barrier and along the
longitudinal
axis of the shaft, such that the shaft pin engages the rising cam.
The shaft also includes a shaft flange that engages the gasket barrier when
the dial
is depressed along the longitudinal axis of the shaft and toward the gasket
barrier. The
controller is in the first position when the dial is pressed along the
longitudinal axis of the
shaft toward the gasket barrier until the shaft pin disengages the rising cam
surface and the
shaft flange engages the gasket barrier. The controller is in the second
position when the
shaft pin is engaging the rising cam surface.
The adjustable sound valve also includes a protection cap that engages the
gasket
base and has one or more protection cap holes for allowing the transmission of
sound. The
protection cap serves to protect the components of the adjustable sound valve
from
damage.
In another aspect of the invention, there is provided an adjustable sound
valve
comprising a passage for sound having a passage size; an attenuator for
varying the
passage size, the attenuator comprising a gasket base having a first gasket
base opening
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and a second gasket base opening, and a plug for cooperating with the second
gasket base
opening to define the passage size; and a controller for controlling the
attenuator, and
configurable between a first position in which the passage size is pre-
determined and a
second position in which the passage size is variable based on the attenuator.
In another aspect, there is provided an adjustable sound valve actively
coupled to a
headgear selected from the set consisting of ear-muffs and helmets, the
adjustable sound
valve comprising a passage for sound having a passage size; an attenuator for
varying the
passage size, the attenuator comprising a gasket base having a first gasket
base opening
and a second gasket base opening, and a plug for cooperating with the second
gasket base
opening to define the passage size; and a controller for controlling the
attenuator, and
configurable between a first position in which the passage size is pre-
determined and a
second position in which the passage size is variable based on the attenuator.
Other aspects and features of the present application will become apparent to
those
ordinarily skilled in the art upon review of the following description of
specific
embodiments in conjunction with the accompanying figures.
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BRIEF DESCRIPTION OF THE DRAWINGS
Embodiments of the present application will now be described, by way of
example
only, with reference to the attached Figures, wherein:
FIG. 1 shows a side view of an ear-muff incorporating an embodiment of the
adjustable sound valve as worn by a user;
FIG. 1A shows a perspective view of an ear-muff incorporating an embodiment of
the adjustable sound valve;
FIG. 2 shows a cross sectional view of an ear-muff incorporating an embodiment
of the adjustable sound valve along line A-A in FIG. 1.
FIG. 3 shows a perspective view of an embodiment of the adjustable sound
valve;
FIG. 4 shows a top view of an embodiment of the adjustable sound valve in an
open position;
FIG. 5 shows a cross sectional view of an embodiment of the adjustable sound
valve along line C-C in FIG. 4;
FIG. 6 shows a top view of an embodiment of the adjustable sound valve in a
closed position;
FIG. 7 shows a cross sectional view of an embodiment of the adjustable sound
valve along line B-B in FIG. 6;
FIG. 8 shows an exploded side view of an embodiment of the adjustable sound
valve;
FIG. 9 shows an exploded top view of an embodiment of the adjustable sound
valve; and
FIG. 10 shows an exploded bottom view of an embodiment of the adjustable sound
valve
DESCRIPTION OF PREFERRED EMBODIMENTS
Figures 1 and 1A respectively show a side view and a perspective view of an
ear-
muff including an embodiment of the adjustable sound valve 1 a first ear muff
10 and a
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second ear muff (not shown), connected to a band 11 by a first band holder 12
and a
second band holder (not shown).
Referring now to Figure 2, the first ear muff 10 includes a cup 14 typically
made of
a rigid material, a sound barrier foam cushion 16, cushion 17, and an
adjustable sound
valve 1 installed in an ear-muff opening 15 in the cup 14. The sound barrier
foam cushion
16 is installed in cup 14 to provide sound absorption. Cushion 17 provides a
comfortable
seal between the ear-muff 10 and the user's head and includes a foam interior
17A of a
material such as a sound barrier foam, and a flexible cover 17B made from
polyvinyl or
other suitable material. Preferably, the adjustable sound valve 1 is described
in further
detail below. As will be understood by one skilled in the art, the adjustable
sound valve
can be integrated into other wearable accessories, such as a helmet.
Figures 3, 4, 5, 6, 7, 8, 9, and 10 show an embodiment of the adjustable sound
valve 1.
Referring now to Figure 3, the adjustable sound valve 1 is controlled through
a dial
3, typically manufactured of plastic, and which can be rotated by a user about
its
longitudinal axis to a user-determined sound attenuation setting, or user
setting, between a
user setting minimum and a user setting maximum. The dial 3 can also be
depressed along
its longitudinal axis, placing it in a first position in which the adjustable
sound valve 1 is
set to a pre-determined attenuation for as long as it is held in the first
position. As detailed
further below, the dial 3 is biased or urged toward an un-depressed second
position, and
releasing the dial 3 causes it to return to its un-depressed second position.
Once the dial 3
returns to its default un-depressed second position, the adjustable sound
valve 1 resumes
attenuating sounds on the basis of the user-setting.
In a further embodiment, the adjustable sound valve 1 includes an attenuation
indicator that provides the user with an indication of the user-determined
sound
attenuation setting. For example, as shown in Figure 4, a marker 3A cooperates
with a
symbol 3B to indicate the current user-determined sound attenuation setting of
the
adjustable sound valve 1. In this example, the thickness of the line in symbol
3B
corresponds to the relative volume of the sound received at the ear, the
thicker portion of
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the line in symbol 3B indicating greater volume (less attenuation), and the
thinner portion
of the line in symbol 3B indicating less volume (greater attenuation).
The dial 3 controls the attenuation by controlling the size of the space, or
passage
for sound, through which sound S travels to the ear. As shown in Figures 4 and
5, dial 3 is
set to greater volume (less attenuation). Accordingly, the adjustable sound
valve provides
a passage for sound between a gasket base 7 and a plug 8 through which sound S
is
transmitted. Sound S enters into the adjustable sound valve 1 through slots 3F
in the dial 3,
flows through the sound passage, and exits through the protection cap holes 9B
and 9C
protection cap 9 to continue on to the user's ear. Thus acting in cooperation,
the gasket
base 7 and the plug 8 act as an attenuator for sound S as it is transmitted
through the
adjustable sound valve 1.
Rotating the dial 3 to increase attenuation and reduce the volume causes the
plug 8
to move closer to gasket base 7, thereby decreasing the size of the passage
sound S that
can be transmitted through it.
Figures 6 and 7 illustrates the adjustable sound valve with the un-depressed
dial 3
set to minimum volume (maximum attenuation), with the plug 8 engaging the
gasket base
7 and completely sealing the gasket opening 7C. No passage is provided for
sound S to
flow on through protection cap holes 9B and 9C of protection cap 9.
Referring now to Figures 8, 9 and 10, dial 3 is attached to a shaft 4 at a
shaft dial
end by the engagement of correspondingly threaded screw 2 and shaft hole 4C.
The dial 3
is typically manufactured from plastic, while the screw 2 and the shaft 4 are
typically
manufactured from a material such as steel or aluminum. Shaft engagement areas
3C and
3D engage the shaft 4 so that rotation of the dial 3 about its longitudinal
axis will result in
corresponding rotation of the shaft 4. A spring 5, or other urging means, is
compressed
between surface 4D and a gasket barrier 6, and urges the dial 3 away from the
gasket
barrier 6. The shaft 4 extends through a gasket barrier shaft hole 61 of
gasket barrier 6,
with gasket barrier 6 positioned between 4E and 4G. A shaft pin 4G extends
away from
the longitudinal axis of shaft 4, and engages cam 6E, which is typically
manufactured
from a material such as steel or aluminum. Shaft 4 is attached to plug 8 at
plug attachment
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portion 4H, which is threaded to correspond to threaded plug nut 8B installed
in plug hole
8C of plug 8.
Gasket barrier 6 includes gasket barrier shaft hole 61 to receive the shaft 4,
one or
more gasket barrier holes 6A to permit the passage of sound, and a cam 6E to
engage the
shaft pin 4G. When the dial 3 is un-depressed, rotation of the dial 3 results
in
corresponding rotation of the shaft 4, causing the shaft pin 4G to move over
the rising
surface of the cam 6E. Rotating the dial 3 and the shaft 4 such that the shaft
pin 4G moves
toward 6F, causes spring 5 to urge dial 3 away from gasket barrier 6, and
moves plug 8
toward gasket base 7.
Typically, the adjustable sound valve 1 is configured to achieve maximum
attenuation, or user setting maximum, when the plug 8 engages gasket base 7 to
completely seal the gasket base opening 7C. Rotating the dial 3 and the shaft
4 such that
the shaft pin 4G moves toward the cam stop 6H causes the dial 3 to move toward
the
gasket barrier 6, compressing the spring 5 further and moving the plug 8 away
from the
gasket base 7. When the dial is un-depressed, minimum attenuation, or the user
setting
minimum, results when the space between the gasket base 7 and the plug 8 is
maximized,
which occurs when the shaft 4 is rotated until the shaft pin 4G engages cam
stop 6H. Both
the gasket base 7 and the plug 8 are typically manufactured of a resilient
material with
sound insulating properties, such as rubber with rubber hardness 70A.
The adjustable sound valve 1 can be put into a first position with pre-
determined
attenuation by depressing the dial 3. Depressing the dial 3 along the
longitudinal axis of
the shaft 4 toward gasket barrier 6 further compresses the spring 5, and
causes shaft flange
4E, or shaft depression limiter, to engage the gasket barrier 6 when the dial
3 is fully
pressed. In this first position the plug 8 moves away from gasket base 7 by a
distance pre-
determined by the interaction of the shaft flange 4E and the gasket barrier 6,
creating a
sound passage of a pre-determined passage size and resulting in pre-determined
attenuation.
As shown in Figure 8, the gasket base 7 includes a first gasket base opening
7A, a
second gasket base opening 7C, cup grooves 7D, protection cap grooves 7E, and
an
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interior surface 7B. First gasket base opening 7A is sealingly mounted by
gasket barrier 6.
Second gasket base opening 7C and plug 8 are adapted to sealingly engage each
other as
plug 8 moves along the longitudinal axis of the shaft 4 toward second gasket
base opening
7C. Cup grooves 7D enable mounting of the adjustable sound valve 1 in the cup
of an ear-
muff. For example, as shown earlier, Figures 1 and 1A show an adjustable sound
valve 1
in which cup grooves 7D engage a cup 14 to fix the position of the adjustable
sound valve
1. Protection cap grooves 7E enable mounting of a protection cap 9, which is
typically
manufactured from plastic, and protects the components of the adjustable sound
valve 1
from damage.
As one skilled in the art will understand, embodiments of the present
invention
may reside in many forms of headwear, such as ear-muffs or helmets.
While the embodiments described herein are directed to particular
implementations
of the adjustable sound valve, it will be understood that modifications and
variations to
these embodiments are within the scope and sphere of the present application.
For
example, the size and shape of many of the features of the adjustable sound
valve can
differ while still providing the same function. Many other modifications and
variations
may occur to those skilled in the art. All such modifications and variations
are believed to
be within the sphere and scope of the present application.
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