U.S. patent application number 11/682208 was filed with the patent office on 2007-10-04 for arrangement for securing a hearing protector to a helmet and a helmet with such an arrangement.
This patent application is currently assigned to AB Kompositprodukter Vikmanshyttan. Invention is credited to Mats Lindgren.
Application Number | 20070226865 11/682208 |
Document ID | / |
Family ID | 37728143 |
Filed Date | 2007-10-04 |
United States Patent
Application |
20070226865 |
Kind Code |
A1 |
Lindgren; Mats |
October 4, 2007 |
ARRANGEMENT FOR SECURING A HEARING PROTECTOR TO A HELMET AND A
HELMET WITH SUCH AN ARRANGEMENT
Abstract
Arrangement for securing a hearing protector to a helmet, which
arrangement comprises a cap holder piece (102) and a helmet piece
(101). The cap holder piece contains a rotary plate (103), a
bistable element (104) and a cap holder element (105), which is
secured by means of the bistable element to the rotary plate to
allow a hearing protection, secured to the cap holder element, to
take up a tilted out and a tilted in position relative to the
rotary plate. The helmet piece comprises means (112, 112') of
attachment to a helmet and a receiving piece (111), in which the
rotary plate is secured, able to turn about an axis of rotation,
which receiving piece includes a resilient tongue (113) essentially
parallel to the axis of rotation and a first stop piece (116)
which, under the action of the resilient tongue and in cooperation
with a second stop piece (132) arranged on the rotary plate,
releasably maintains the rotary plate in a first rotational
position relative to the receiving piece. To prevent the cap holder
piece from accidentally leaving the first rotational position, the
arrangement includes a first projection (119) extending from the
receiving piece essentially parallel to the axis of rotation, which
in the first rotational position limits the motion of the rotary
plate toward the resilient tongue by thrusting against the cap
holder piece.
Inventors: |
Lindgren; Mats;
(Vikmanshyttan, SE) |
Correspondence
Address: |
HOLLAND & HART, LLP
P.O BOX 8749
DENVER
CO
80201
US
|
Assignee: |
AB Kompositprodukter
Vikmanshyttan
Vikmanshyttan
SE
|
Family ID: |
37728143 |
Appl. No.: |
11/682208 |
Filed: |
March 5, 2007 |
Current U.S.
Class: |
2/6.2 |
Current CPC
Class: |
A42B 3/166 20130101 |
Class at
Publication: |
002/006.2 |
International
Class: |
F41H 1/04 20060101
F41H001/04 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 10, 2006 |
SE |
0600541-7 |
Claims
1. Arrangement for securing a hearing protector to a helmet, which
arrangement comprises a cap holder piece (102) and a helmet piece
(101), wherein the cap holder piece contains a rotary plate (103),
a bistable element (104) and a cap holder element (105), which is
secured by means of the bistable element to the rotary plate to
allow a hearing protection, secured to the cap holder element, to
take up a tilted out and a tilted in position relative to the
rotary plate, and the helmet piece comprises means (112, 112') for
the attachment to a helmet and a receiving piece (111), in which
the rotary plate is secured, pivotal about an axis of rotation,
which receiving piece includes a tongue (113) which is resilient in
a direction essentially parallel to the axis of rotation and a
first stop piece (116) which, under the action of the resilient
tongue and in cooperation with a second stop piece (132) arranged
on the rotary plate, releasably maintains the rotary plate in a
first rotational position relative to the receiving piece,
characterized by a first projection (119) extending from the
receiving piece essentially parallel to the axis of rotation, which
in the first rotational position limits the motion of the rotary
plate toward the resilient tongue by bearing against the cap holder
piece.
2. Arrangement according to claim 1, wherein the first projection
(119) is arranged so that in the first rotational position it
limits the motion of the rotary plate (103) by bearing against the
bistable element (104).
3. Arrangement according to claim 1, containing a third stop piece
arranged on the rotary plate (103) which, under the action of the
resilient tongue (113) and engaging with the first stop piece
(116), releasably maintains the rotary plate in a second rotational
position relative to the receiving piece, wherein the arrangement
contains a second projection (118) which, in the second rotational
position, limits the motion of the rotary plate toward the
resilient tongue by bearing against the cap holder piece.
4. Arrangement according to claim 3, wherein the second projection
(118) is arranged so as to limit the motion of the rotary plate by
bearing against the bistable element in the second rotational
position.
5. Arrangement according to claim 3, wherein the first and second
projection are formed as a continuous projection.
6. Arrangement according to claim 1, wherein the rotary plate (103)
is secured releasably in the receiving piece (111) by snap action
under the influence of the resilient tongue (113).
7. Arrangement according to claim 1, wherein the means for
attachment of the helmet piece to a helmet include at least one
flexible male part (112c) for separable snap fastening to a
corresponding female part on the helmet.
8. Arrangement according to claim 1, further including a helmet.
Description
FIELD OF THE INVENTION
[0001] The invention concerns an arrangement for securing a hearing
protector to a helmet according to the preamble of patent claim 1.
The invention also concerns a helmet with such an arrangement.
[0002] 1. Background
[0003] Nowadays, thanks to laws and regulations, many work
situations require the employer to provide both a protective helmet
and hearing protection to guard against various risks to the
personnel during their work. One example is felling of trees with a
chain saw. Most of the manufacturers of protective helmets have
therefore adapted the configuration of the helmet as a standard
model so that hearing protection can be attached to the helmet in
that there is a slot or the like in the edge of the helmet on
either side above the position of the ear. The hearing protection
for the helmet is then provided with a helmet part that can be
attached to the helmet in the slot, for example, by a snap
fastener.
[0004] The hearing protection is worn during work in a protecting
position or a working position, in which the caps of the hearing
protection lie tightly against the user's head around the ears.
Besides being worn in the working position, it should also be
possible to move the caps into a resting position when the
protection is not needed at the moment, e.g., during a work break.
It is therefore desirable for the caps to be moved into a resting
position without having to remove the hearing protection from the
helmet. One such commonly occurring position of rest is taken up by
rotating the ear caps backward and upward so that they are placed
and remain outside of the helmet. In order for the caps to pass the
edge of the helmet and take up the downward rotated position, it is
often necessary to first move them into a tilted-out position just
outside the ears. It is advantageous to move the ear caps into and
maintain them in the tilted-out position, e.g., to make possible a
short conversation while working.
[0005] Different helmet manufacturers use different slots or other
elements to enable the fastening of the hearing protection to the
helmet. It is therefore desirable for the hearing protection to
have easily replaceable parts or adapters which fit the slots,
etc., of the different helmet manufacturers. In this way, the very
same hearing protection can be easily used for helmets of different
brand.
[0006] 2. Prior Art
[0007] FIG. 1a-c and 2 show a previously known arrangement for
fastening of a hearing protection to a helmet. FIG. 1a is a front
plan view of the known arrangement. FIGS. 1b and c are side views,
where FIG. 1c shows the components of the arrangement taken apart.
The known arrangement contains a helmet piece 1 and a compound cap
holder piece 2.
[0008] As appears most clearly from FIG. 1c, the cap holder piece 2
contains a rotary plate 3 with a radially projecting annular flange
31, a bistable element in the form of a two-tongued leaf spring 4,
a cap holder bracket 5 and a hinged cover plate 6. The leaf spring
4 is fixed by one end in the rotary plate 3 and by its other end to
the cap holder bracket 5. The cap holder bracket has two elongated
slots for adjustable fixation of an ear cap (not shown). The
two-tongued leaf spring 4 has a bistable configuration, so that the
cap holder bracket 5 can be moved between and held in the tilted-in
position as shown by FIG. 1b and a position tilted out to the right
(not shown).
[0009] The helmet piece 1 contains a receiving piece 11 and an
elastic fixation tongue 12 projecting downward from the receiving
piece. The fixation tongue 12 is configured to snap into a slot
formed in a helmet (not shown). FIG. 2 shows a somewhat different
helmet piece 1' on a smaller scale. The helmet piece 1' differs
from the above described helmet piece 1 simply in that the fixation
tongue 12' has a different configuration to fit into a helmet whose
slot has a different geometry. The receiving piece 11 of the helmet
piece 1' is identical to the receiving piece 11 shown in FIG. 1a-c.
The receiving piece 11 in both helmet pieces 1 and 1' contains an
elastically resilient tongue 13 with a forward projecting flange 17
shaped as a circular arc, an upper flange 14 of semicircular shape,
arranged around the tongue 13 and projecting radially inward, a
lower edge 15 shaped as a circular arc, and a first forward
projecting stop piece 16.
[0010] The rotary plate 3 is held and able to rotate in the
receiving piece 11 in that the annular flange 31 of the rotary
plate is inserted beneath the radially inward projecting flange 14
of the receiving piece. The projecting flange 17 of the resilient
tongue 13 thus engages with the radially inward pointing
cylindrical surface on the annular flange 31. The elasticity of the
resilient tongue 13 allows the annular flange of the rotary plate 3
to engage and disengage from this rotational fastening by a snap
action. The rotary plate 3 is inserted into and removed from the
receiving piece 1 by a relative displacement in the vertical
direction.
[0011] FIGS. 1a and 1b show the cap holder piece 2 in the working
position. In this position, the two-tongued leaf spring 4 has taken
up its position tilted in to the left in FIG. 1b and the rotary
plate 3 has taken up a rotational position relative to the
receiving piece 11, in which the cap holder bracket 5 is directed
downward. In order to move the cap holder bracket 5 into a resting
position arranged outside the helmet, one first presses the cap
holder bracket to the right in FIG. 1b, whereupon the leaf spring 4
assumes its tilted out position. After this, one turns the rotary
plate 3 about 100 degrees counterclockwise per FIG. 1a, relative to
the receiving piece 11. In this rotational position, a second stop
piece 32 formed on the annular flange 31 is caused to engage with
the first stop piece 16 of the receiving piece, projecting in the
direction of the rotary plate. The purpose of this engagement is to
hold the cap holder piece in the resting position with a hearing
protection mounted in place.
[0012] One problem with the above described known arrangement,
however, is an inability to maintain the cap holder piece in the
resting position. The force of gravity acting on the hearing
protection and the lever arm, defined by the distance between the
hearing protection and the axis of rotation of the rotary plate,
produces a torque which strives to disengage the first and second
stop from each other. Studies have shown that the hearing
protection can be subjected to forces amounting to around 5-8 G,
for example, when the user is walking on a stairway. The two stops
can then become disengaged from each other, whereupon the cap
holder piece with the hearing protection rotates downward from its
resting position. This is often perceived as an annoyance by the
user. To prevent such a downward rotation, the user might tilt in
the cap holder piece in the upward rotated resting position so that
the bistable leaf spring presses the hearing protection against the
helmet shell. This results in relatively large forces, for example,
at the fastening of the helmet piece in the helmet, which are
liable to damage the helmet and/or the helmet piece of the
arrangement.
[0013] Protective helmets can be made from ABS, for example. More
recently, PE has also come to be used for manufacture of protective
helmets. Due to the lower shape stability of PE, some of the
problems connected with the above described known arrangement are
even more serious when using protective helmets made of PE.
SUMMARY OF THE INVENTION
[0014] One purpose of the present invention is therefore to provide
an improved arrangement for fastening of a hearing protection to a
helmet.
[0015] Another purpose is to provide an arrangement which leads to
a more secure retention of the hearing protection in a resting
position rotated upward outside the helmet.
[0016] Furthermore, one purpose is to provide an arrangement which
reduces the risk of damage to the helmet and the arrangement.
[0017] Yet another purpose is to provide an arrangement which
reduces the problems arising when used on helmets made from PE.
[0018] One further purpose is to provide an arrangement which is
reliable, durable, and easy to use.
[0019] A further purpose is to provide an arrangement comprising a
limited number of constituent parts, and which is relatively simple
and cheap to make.
[0020] These and other purposes are achieved with an arrangement of
the kind indicated in the preamble of patent claim 1, which
arrangement has the special technical features indicated in the
characterizing passage of the claim.
[0021] The invention is based on the insight that the above
described problem with swinging down from the resting position in
the previously known arrangement is caused by the resilient tongue
giving way and bending in toward the helmet when the first and
second stops are pressed together if the cap holder piece in the
resting position is subjected to a force which strives to turn the
cap holder piece into the working position. Since the stops are
pressed together during the turning, the rotary plate is twisted
about a horizontal axis which is perpendicular to the axis of
rotation of the rotary plate. In this process, the lower part of
the rotary plate with the second stop piece is pressed in the
outward direction, from the first stop piece on the receiving
piece, and the upper part of the rotary plate diametrically
opposite the second stop is pressed inward toward the resilient
tongue. Due to the elasticity of the tongue, it allows this
twisting or slanting of the rotary plate to occur, whereupon the
second stop loses its engagement with the first stop and can move
past it. Yet the resilient tongue has to have a certain elasticity
in order to let the rotary plate of the cap holder piece snap in
place and be released from the receiving piece of the helmet
piece.
[0022] According to the invention, this problem is solved with a
projection protruding from the receiving piece essentially parallel
to the axis of rotation. The projection is arranged on the
receiving piece so that, at least in the resting position, it
limits or prevents the movement of the rotary plate inward towards
the resilient tongue by bearing against some portion of the cap
holder piece. In this way, the slanting or twisting about a
horizontal axis which is perpendicular to the axis of rotation of
the rotary plate is limited or prevented in the resting position.
The second stop is thus not able to become disengaged from the
first stop, unless a relatively large torque is applied to the cap
holder piece in the direction towards the working position.
[0023] The projection is conveniently arranged so that in the
resting position it prevents a slanting of the rotary plate by
thrusting against the bistable element projecting from the rotary
plate. In this way, the projection can be placed radially outside
the rotary plate, so that the rotary motion of the rotary plate
about the axis of rotation is not prevented.
[0024] The rotary plate advisedly will have a third stop piece
which, engaging with the first stop piece on the receiving piece,
defines a second resting position which is reached by turning in
the opposite direction as compared to the first resting position.
The arrangement will then have a second projection to prevent
slanting of the rotary plate in the second resting position. The
arrangement can then be used on both sides of the helmet and at the
same time allow the cap holder piece to take up a stable
backward-turned resting position in either case, by clockwise or
counterclockwise rotation, respectively. In such a case, the second
projection is also advisedly arranged so as to prevent a slanting
of the rotary plate by thrusting against the bistable element.
[0025] The first and second projection can either be formed as
separate elements or as a continuous projection. In this way, one
has freedom of choice in the configuration which is most suitable
in terms of manufacturing technology, strength, esthetic or other
reasons.
[0026] The rotary plate is advisedly secured releasably in the
receiving piece by snap action under the influence of the resilient
tongue. This allows for a simple replacement of the helmet piece so
that the very same cap holder piece can be used for helmets with
different types and shapes of fasteners for the hearing protection
by varying the helmet piece.
[0027] The means of attachment of the helmet piece to a helmet
advisedly include at least one flexible male part for separable
snap fastening to a corresponding female part on the helmet. In
this way, a simple fastening and removal of the arrangement from
the helmet is made possible, which means that the very same
arrangement can be used for different helmets.
[0028] The invention also involves a helmet containing such an
arrangement.
[0029] Further properties and advantages of the arrangement and the
helmet according to the invention shall appear from the following
detailed description and the patent claims.
BRIEF DESCRIPTION OF DRAWINGS
[0030] The following provides a detailed description of sample
embodiments with regard to the drawings, where:
[0031] FIG. 1a-c is a front plan view, a side view and an exploded
view of a cap holder arrangement according to the prior art.
[0032] FIG. 2 is a front plan view of a part making up a prior
known arrangement.
[0033] FIG. 3 is a front plan view of a configuration of the
arrangement according to the invention, showing the arrangement in
a working position.
[0034] FIG. 4a-c shows a helmet piece making up the arrangement
shown in FIG. 3, where FIG. 4a is a front plan view, FIG. 4b is a
rear plan view, FIG. 4c is a side view and FIG. 4d is a section
along line A-A of FIG. 4a.
[0035] FIG. 5 is a front plan view showing a part of the helmet
piece of FIG. 4a on magnified scale.
[0036] FIG. 6 is a partially transparent front plan view of the
arrangement shown in FIG. 3, showing the arrangement in the resting
position.
[0037] FIG. 7 is a cross section along line B-B of FIG. 6 with some
parts removed.
DETAILED DESCRIPTION OF EMBODIMENTS
[0038] The following describes two sample embodiments of the
invention with regard to FIGS. 3-7. In these drawings, the
embodiment shown in FIG. 6 differs from the embodiment shown in
FIG. 3-5 and 7 merely in that the helmet piece of the arrangement
is shaped differently in order to fit different helmets whose slots
for attachment of the hearing protection have a different
geometrical configuration.
[0039] The arrangements according to the invention, shown in FIG.
3-7, like the known arrangement shown in FIG. 1a-c, contain a
helmet piece 101 and a cap holder piece 102.
[0040] FIG. 4a-c shows only the helmet piece 101 for a first
embodiment of the invention. FIG. 5 shows on magnified scale only a
receiving piece 111 of the helmet piece 101.
[0041] The helmet piece 101 contains a receiving piece 111 and an
elastic fixation tongue 112, projecting downward from the receiving
piece. The fixation tongue 112 is configured as a male part and it
contains two outer tongue pieces 112a, 112b and a central flexible
tongue piece 112c with a snap hook for fastening to a corresponding
female part in the form of a fixation slot which is arranged in the
helmet.
[0042] The receiving piece 111 of the helmet piece contains an
elastically resilient tongue 113 with a circular-arc flange 117
projecting forward (to the left in FIG. 4d). The receiving piece
111 also contains a semicircular flange 114, projecting radially
inward and arranged around the tongue 113, a lower circular-arc
edge 115, and a first stop piece 116 projecting forward.
Furthermore, the helmet piece 101 according to the invention
contains a first 118 and a second 119 projection, extending forward
(to the left in FIGS. 4c and 4d). The projection 118, 119 is formed
as a single piece with the receiving piece 111 and is placed partly
on and radially outside of the semicircular flange 114 of the
receiving piece, which projects radially inward.
[0043] In the embodiment shown in FIG. 6, the helmet piece 101
contains a receiving piece 111 identical to the above described
receiving piece with a somewhat modified fixation tongue 112'.
[0044] Referring in particular to FIGS. 3 and 7, the cap holder
piece 102 of the arrangement contains a rotary plate 103 with a
radially projecting annular flange 131. The cap holder piece also
contains a cap holder element in the form of a cap holder bracket
105 for fastening a hearing protection (not shown) and a hinged
cover plate 6. Like the known arrangement shown in FIG. 1c, the cap
holder piece also contains a bistable element in the form of a
two-tongued leaf spring 104 (see FIG. 7). The leaf spring 104 is
fixed by its one end in the rotary plate 103 and by its other end
to the cap holder bracket 105. The two-tongued leaf spring 104 has
a bistable configuration, so that the cap holder bracket 105 can be
moved between and held in a position tilted in against the ear and
a position tilted out away from the ear.
[0045] As is shown most clearly by FIG. 7, the rotary plate 103 is
fastened and can rotate in the receiving piece 111 in that the
annular flange 131 of the rotary plate is inserted beneath the
radially inwardly projecting flange 114 of the receiving piece. The
projecting flange 117 of the resilient tongue 113 is then engaged
with the radially inwardly turned cylindrical surface on the
annular flange 131. The elasticity of the resilient tongue 113
allows the annular flange 131 of the rotary plate 103 to be engaged
by and disengaged from this fastening by snap action. The rotary
plate 103 is inserted into the receiving piece 111 by pressing the
rotary plate upward when the receiving piece is in the position
shown in FIG. 3.
[0046] FIG. 3 shows the cap holder piece 102 in the working
position. In this position, the two-tongued leaf spring 104 has
taken up its position tilted in against the ear and the rotary
plate 103 has taken up a rotational position relative to the
receiving piece 111, in which the cap holder bracket 105 is
directed downward. In order to move the cap holder bracket 105 into
the resting position situated outside of the helmet, the cap holder
bracket is first pressed outward from the ear, whereupon the leaf
spring 104 takes up its tilted out position. After this, the rotary
plate 103 is turned about 100 degrees clockwise per FIG. 3,
relative to the receiving piece 11, and it takes up the rotational
position shown in FIG. 6. FIG. 7 also shows this resting position,
and it can also be seen here how the bistable spring 104 has taken
up its tilted out position. In this resting position, a second stop
132 configured on the annular flange 131 is brought into engagement
with the first stop 116 of the receiving piece 111, projecting
forward in the direction of the rotary plate 103.
[0047] As is clearly shown in FIG. 7, the leaf spring 104 in the
resting position is just beyond the projection 119, at only a
slight distance from it. If the lower part of the rotary plate 103
in FIG. 7 and the annular flange 131 are pressed to the left in the
direction of the resilient tongue 113, the leaf spring 104 will
make contact with the projection 119 and thereby prevent further
movement to the left. Hence, a relatively large torque on the
rotary plate in the direction of the working position
(counterclockwise in FIG. 6) is needed to make the second stop 132
pass by the first stop 116 so that these stops are disengaged from
each other and the cap holder piece can return to the working
position. Thanks to the relatively large force required to
disengage the two stops 132 and 116 from each other, the cap holder
piece 102 is prevented from unintentionally dropping down from its
position of rest away from the helmet, for example, when the user
is walking on stairs, or during some other motion where large
accelerations and decelerations act on the hearing protection and
the cap holder piece. Thus, the user does not need to try to
prevent such unintentional swinging down of the cap holder piece by
tilting the cap holder bracket in the resting position so that the
hearing protection is pressed against the helmet shell. This also
avoids the damage to the helmet and the helmet piece which might
otherwise occur if the bistable leaf spring in the resting position
happens to press the hearing protection against the helmet
shell.
[0048] It should be noted that the projection 119 prevents a
slanting of the rotary plate 103 only when the leaf spring 104 is
placed in front of the projection and the cap holder piece thus
rotates to the resting position. When the cap holder piece is in
the working position, for example, or some other rotational
position, the projection 119 does not affect the movement of the
rotary plate. It is therefore possible, for example when the rotary
plate is in the rotational position corresponding to the working
position, to fasten or remove the rotary plate and the cap holder
piece from the receiving piece and the helmet piece, thanks to the
elasticity of the resilient tongue.
[0049] As shown by FIG. 3-6, yet another projection 118 is arranged
on the receiving piece 111 of the helmet piece 101. This projection
has the same configuration and function as the projection 119 and
it ensures that the cap holder piece is held in another resting
position (not shown), in which the cap holder piece has rotated
about 100 degrees counterclockwise from the working position shown
in FIG. 3. For the same reason, the arrangement is also provided
with a third stop (not shown), which is arranged on the rotary
plate and which has a position and a configuration corresponding to
the second stop.
[0050] Two sample embodiments of the invention have been described
above. However, it is clear that the invention is not limited to
the above-described embodiments, but rather it can be varied freely
within the framework of the following patent claims. For example,
the means of fastening the arrangement to a helmet which are
arranged on the helmet piece can take on a number of different
forms in order to fit different helmets on the market. The cap
holder piece, of course, can also be variously shaped or replaced
by different cap holder elements in order to fit different hearing
protection devices occurring on the market.
* * * * *