Field of the Invention
[0001] The present invention relates to the ventilation of helmets, in particular it relates
to improving the cooling performance while maintaining the aerodynamics of sport helmets.
The main factors contributing to the the cooling performance of a helmet are forced
convection and the blocking of heat irradiation, e.g., sun irradiation.
Background of the Invention
[0002] The primary goal of a helmet is to protect the wearer's head on impact. In order
to absorb the energy from the impact, the helmet typically contains a shock absorbent
material such as expanded polystyrene (EPS). The helmet may further comprise an outer
casing. This outer casing may serve different purposes such as for the protection
of the absorbent material, for the distribution of impact forces over a wider area,
for preventing the helmet to crush of brake in smaller parts, for providing a smooth
aerodynamic outer surface and for aesthetic reasons.
[0003] A disadvantage of helmets is that they hinder the cooling of the wearer's head. This
may be solved be providing fixed openings in the helmet that allow air to flow onto
the wearer's head thereby providing a cooling effect. However, the openings are not
always favoured by the wearer, for example when it rains or when aerodynamics prevail
over the cooling effect.
[0004] This can be overcome by closable air inlets having an open and closed position. In
the open position, air can flow into the helmet and provide the ventilation and, in
the closed position, air flows over the helmet's outer surface. One way to achieve
such a closable air inlet is by a cover element that is embedded between the outer
casing of the helmet and the absorbent material. In a closed position, the cover element
then covers an air inlet opening in the absorbent material. To open the ventilation,
the cover element is then slid underneath the outer cover thereby exposing the air
inlet. Alternatively, the cover element is slid along the outside of the outside casing.
[0005] While providing ventilation, the above solution still has some drawbacks. A first
drawback is that the wearer's head may be exposed to sun radiation in the open position
when the air inlet is on the topside of the helmet. This exposure partly cancels out
the ventilation effect. A second drawback is that the airflow is often suboptimal
because the air is not optimally guided upon entering the air inlet. These two drawbacks
are also present in helmets with fixed air inlets. A third drawback is that extra
space must be foreseen in, on top or under the outer cover to embed the cover element
when it is in the open position. This further increases the thickness of the helmet
or results in an uneven outer surface which affects the aerodynamics of the helmet.
Summary of the Invention
[0006] It is an object of the invention to overcome the above drawbacks and provide a closable
air inlet for a helmet which is more aerodynamic at the outside, does not add thickness
to the helmet, prevents sun irradiation onto the wearer's head and provides an aerodynamic
airflow into the helmet.
[0007] This object is achieved by a sports helmet comprising a closable air inlet for ventilation
of the wearer's head; wherein the air inlet comprises:
- blinds movable between an open and closed position,
- wherein, in the closed position, the blinds close the air inlet,
- wherein the blinds are positioned such that, in the open position, air is guided into
the helmet along the blinds.
[0008] Ventilation and thus forced convection of the wearer's head is thus provided by blinds.
Blinds are thin plate like structures or lamellas that essentially only comprise two
main surfaces, a top and bottom surface. When referring to the surface of a blind
within this disclosure, it is a reference to this bottom or top surface. In both open
and closed positon the surfaces of the blinds are substantially parallel to each other.
In a closed position, the surfaces further form a single surface or plane. In an open
position, each blind defines a plane separate from the other blinds such that an air
gap is defined in between consecutive blinds through which the air can flow into the
helmet.
[0009] By the surface of the blinds sunlight will be blocked. The more the sunlight radiates
a blind's surface perpendicularly, the more efficient the sunlight is blocked. As
the strongest radiation is mostly received on top of the helmet and as the blinds
will be most effective for ventilation when parallel to the horizon, an optimal ventilation
and irradiation blocking is achieved by a helmet according to the invention. By the
same principle, the blinds will also protect the wearer better from rain.
[0010] Furthermore, the blinds will guide the incoming air flow along their surface. Therefore,
by positioning the blinds appropriately, an optimal air flow inside the helmets is
achieved. Moreover, by adjusting the position of the blinds, the direction of the
air flow may be further adjusted according to the air flow conditions.
[0011] As the blinds do not need to be slid away from the air inlet, no extra space must
be foreseen, either inside or outside the outside cover. Therefore an even outside
surface without bumps of or major irregularities can be achieved resulting in an aerodynamic
air flow along the helmet, especially when the blinds are closed. It is thus an advantage
that improved aerodynamics are obtained compared with existing solutions.
[0012] Advantageously, in the open position, the blinds are positioned such that air is
guided into the helmet along the wearer's head. This way, the least air resistance
and maximum cooling is achieved.
[0013] According to an embodiment the helmet comprises an outside surface along which the
air is guided when the blinds are in the closed position; and wherein, in the open
position, the blinds are in a tilted position with respect to the outside surface
of the helmet.
[0014] By the tilted position, the air flowing along the outside surface of the helmet will
be directed into the helmet.
[0015] More advantageously, the blinds are rotatable around a rotation axis between the
closed and tilted position; and wherein the rotation axis of each blind is parallel
to a tangent of the blind and perpendicular to a direction of the air flow over the
blind when the blind is in the closed position.
[0016] The tilting of the blinds is thus achieved by a rotation of each blind around a rotation
axis which is parallel to the surface of the blind. Furthermore, the blind is positioned
such that the air gap intercepts the air flow in the most optimal position. The has
the advantage that the least resistance is achieved when guiding the airflow inside
the helmet.
[0017] According to a further embodiment, the helmet comprises a front and back portion
thereby defining a front and back portion of the blinds; and wherein the blind is
rotatable around the front portion such that the blind is tilted inward the helmet
when in the open position.
[0018] The front portion of the helmet thus corresponds to the front of the helmet, i.e.,
the portion running towards the face of the wearer. Because the rotation axis is positioned
towards the front side of the blind, the blind will mainly rotate inwards into the
helmet when moving into the open position. This has the advantage that the blind thus
not stick out of the helmet's outer surface when in the open position. Moreover, the
blinds will not exhibit a large momentum towards the open position when they are closed.
This prevents that the blinds would accidently open by a strong air flow during use.
[0019] In the open position, the blinds may further be in a translated position with respect
to the outside surface of the helmet.
[0020] According to an embodiment, the closable air inlet comprises an engaging means movable
from a first position to a second position such that the blinds are moved between
the open and closed position when the engaging means is moved between the first and
second position.
[0021] This allows an easy operation by the wearer as only a single movement is required
to get the blinds in the open position.
[0022] According to a further embodiment, the blinds are pivotally mounted in the engaging
means; and wherein the blinds are moved from the closed position to the translated
position when moving the engaging means from the first to second position; and wherein
the helmet further comprises a guiding means arranged such that the blinds move from
the closed position to the tilted position by interaction with the guiding means when
the engaging means moves from the first to second position.
[0023] This way, a combined rotation of all the blinds is achieved by a single translation.
Furthermore, by the guiding means in the helmet, the blinds can be further secured
apart from the fixation points of the rotation axis thereby assuring that the blinds
can withstand the forces exhibited by the air flow.
[0024] The air inlet may further comprise a cover covering the blinds and comprising openings
to guide the air to the blinds.
[0025] By the cover, the air may be filtered upon entering, for example to prevent that
insects fly into the helmet through the blinds. Moreover, the cover may have a pattern
different from the blinds allowing further personalization of the helmet. The cover
also strengthens the overall structure of the helmet thereby making the helmet better
resistant to impact. To this respect, the cover preferably comprises an impact absorbing
structure.
[0026] The engaging means may further be connected to the cover such that the engaging means
is moved from the first to second position when the cover is moved along the helmet's
outer surface. The engaging means thus serves a dual purpose, i.e., as a cover for
the blinds and for moving the blinds. This has the advantage that no further space
on the outside cover of the helmet must be sacrificed to embed the engaging means
resulting in a slick and visually attractive design.
[0027] According to an embodiment, the helmet further comprises an actuation means comprising
an actuator for moving the blinds from the first to second position in an automated
way. This way, the wearer does not have to move the blinds manually because the actuator
will move the blinds between the open and closed position.
[0028] The actuation means may further comprise a temperature sensor. The actuator is then
driven by the temperature sensor, i.e., when the temperature exceeds a certain threshold
temperature as measured by the sensor, then the actuation means moves the blinds to
the open position by the actuator. The other way around, when the temperature drops
below a certain second threshold temperature as measured by the sensor, then the actuation
means moves the blinds to the closed position. This way, the blinds are operated in
a fully automated way without the need for any manual interaction from the wearer.
[0029] According to an embodiment, the actuator comprises a material which changes shape
by a change in temperature arranged such that the blinds move between the open and
closed position depending on the temperature of the material. This has the advantage
that the automated movement of the blinds can be achieved without any motorized means
and thus without any energy storage such as a battery.
[0030] According to a further embodiment the actuation means further comprises a sensor
for measuring the tilting of the helmet; and the helmet further comprises a processing
unit arranged to configure a position of the blinds in the open position and thereby
the air flow into the helmet based on the measured tilting.
[0031] This has the advantage that the air flow into the helmet may be made constant such
that a constant cooling effect and constant aerodynamic effect is achieved.
Brief Description of the Drawings
[0032]
Fig. 1A illustrates a side view of a helmet comprising a closable air inlet according
to an embodiment of the invention when the air inlet is closed; and
Fig. 1B illustrates a side view of a helmet comprising a closable air inlet according
to an embodiment of the invention when the air inlet is open; and
Fig. 2A illustrates a detailed view of an engaging means for opening and closing the
air inlet of the helmet according to Fig. 1A and Fig. 1B when the air inlet is in
the closed position; and
Fig. 2B illustrates a detailed view of an engaging means for opening and closing the
air inlet of the helmet according to Fig. 1A and Fig. 1B when the air inlet is in
the open position; and
Fig. 3A illustrates the air flow along the helmet of Fig. 1A when the air inlet is
in the closed position; and
Fig. 3B illustrates the air flow along and into the helmet of Fig. 1B when the air
inlet is in the closed position; and
Fig. 4 illustrates a three dimensional view of the helmet according to Fig. 1B when
the air inlet is in the open position; and
Fig. 5 illustrates a three dimensional view of the helmet according to Fig. 1B when
the air inlet is in the open position with a cover mounted on top of the air inlet;
and
Fig. 6 illustrates an actuation means for opening and closing an air inlet of a helmet
according to an embodiment of the invention.
Detailed Description of Embodiment(s)
[0033] Fig. 1 to Fig. 5 illustrate different views and details of a helmet 100 comprising
a closable air inlet 120 according to an embodiment of the invention. The helmet 100
comprises a front portion and rear or back portion thereby defining a front direction
115 and rear direction 116 with respect to the helmet 100. The face of a wearer of
the helmet is facing the front direction and the back of the head of the wearer is
facing the rear direction. The helmet 100 comprises a closable air inlet 120 in the
front portion of the helmet. The air inlet 120 can be arranged in a closed positon
and an open position. In the closed position an air flow 301 will flow along the outer
surface 303 of the helmet and no air is entering the helmet through the air inlet
120. In an open position an air flow 302 will flow into the air inlet 120 and flow
along the wearer's head thereby providing a cooling effect. The airflow 302 exits
the helmet 100 through holes in the rear portion of the helmet 100.
[0034] The air inlet comprises blinds 101 to 104 movable between a closed position as illustrated
by Fig. 1A, 2A and 3A and an open position as illustrated by Fig. 1B, 2B, 3B, 4 and
5. When the blinds are in the open position, the air inlet 120 is in the open position,
when the blinds are in the closed position, the air inlet 120 is in the closed position.
[0035] Blinds 101 to 104 are attached to an engaging means 130. The blinds are rotatable
around a rotation axis, for example axis 131 for blind 102, within the engaging means
130, i.e., blinds 101-104 are pivotally mounted in the engaging means 130. In the
closed position, the blinds 101-104 form a single flat surface preventing the air
from entering the air inlet. In the open position, the blinds 101-104 are tilted 111
with respect to the open position around their respective rotation axis. Engaging
means 130 is mountable in helmet 100. Engaging means 130 is movable between a first
and second position by a translation along the outer surface of the helmet. In the
first position as shown in Fig. 1A, the blinds are closed. In order to open the blinds,
the engaging means 130 is slid along direction 110 to the back of the helmet. By the
translation 110, the blinds are tilted inwards the helmet by a slope element 119 serving
as guiding element for the blinds. Blinds 101-104 interact with slope element 119
an thus follow the slope of slope element 119 during the translation 110 of the engaging
means 130.
[0036] The rotation axis of blinds 101-104 providing the tilting is preferably parallel
to the blind itself and located in the front portion 117 of the blind. The front portion
117 of the blind is the portion which is located towards the front 115 of the helmet
100. The back portion 118 of the blind is then the portion which is located towards
the back 116 of the helmet 100. This is illustrated in Fig. 1B where line 113 illustrates
the plane of the blind when closed and line 114 illustrates the plane of the blind
when in the open position. The angle 112 between plane 113 and 114 then illustrates
the tilting angle of the blind with respect to the outer surface 303 of the helmet
100. This way, the blind will make the tilting movement into the helmet. Moreover,
the blind is in a stable position as incoming air will not exhibit a large rotation
momentum on the blind.
[0037] When the blinds are in the open position the air flow 302 is guided into the helmet
100 by the blinds, i.e., into the air gaps created by the opened blinds. The blinds
themselves guide the air flow 302 into the helmet. More preferably, in the open position,
the blinds are positioned such that the air flow 302 is guided along the head of the
wearer.
[0038] Preferably, a cover 502 covers blinds 101 to 104. Cover 502 is further attached to
the engaging means 130 such that the translation 119 to the open position or the translation
501 to the closed position may be performed by moving the cover along the outer surface
303 of the helmet in respective direction 119 or 501. Holes are provided in cover
502 such that the air flow 302 can pass through the cover when the air inlet is open.
Cover 502 provides a reinforcement of the helmet 100 at the air inlet 120. Cover 502
may comprise an impact absorbent structure such that the wearer's head is also protected
around the air inlet. Cover 502 and the impact resistant structure may be chosen such
that the helmet 100 withstands a kerbstone impact as specified in standard EN1078.
The impact absorbance may for example be provided by a honeycomb structure made of
Polycarbonate.
[0039] Fig. 6 further illustrates an actuation means 600 for moving the blinds 101-104 between
the open and closed position. Actuation means 600 comprises an actuator 604 for performing
the movement of the blinds in an automated way. Actuator 604 may for example correspond
to a motor for turning the blinds 101-104. Actuator 604 may also correspond to a linear
actuator for moving the engaging means 130 or cover 502 between the first and second
position.
[0040] According to a further embodiment, actuation means 600 comprises a control unit 603
for controlling the actuator 604. Actuation means 600 may then further comprise a
temperature sensor 601 providing a measure of the temperature outside or inside the
helmet to the control unit 603. Control unit 603 is then further configured to move
the blinds to the open position when the temperature exceeds a first threshold temperature.
Control unit 603 may be further configured to move the blinds to the closed position
when the temperature drops below a second threshold temperature.
[0041] Actuation means 600 may further comprise a tilting sensor 602 for measuring the tilting
position of the helmet. The tilting position is the angle corresponding to the tilting
of the head of the wearer with respect to a horizontal reference plane such as for
example a plane perpendicular to the direction of the gravity. By the tilting of the
head and thus the helmet 100, the airflow 302 entering the helmet will vary. In order
to make the airflow into the air inlet more stable, the control unit 603 will vary
the position of the blinds depending on the tilting of the helmet measured by the
tilting sensor.
[0042] According to another embodiment, actuator 604 comprises a material which deforms
by a changing temperature. This deformation is then used to control the position of
the blinds 101-104 from completely opened to completely closed. This way an automated
opening of the blinds is achieved without a need for energy storage such as a battery.
[0043] Although the present invention has been illustrated by reference to specific embodiments,
it will be apparent to those skilled in the art that the invention is not limited
to the details of the foregoing illustrative embodiments, and that the present invention
may be embodied with various changes and modifications without departing from the
scope thereof. The present embodiments are therefore to be considered in all respects
as illustrative and not restrictive, the scope of the invention being indicated by
the appended claims rather than by the foregoing description, and all changes which
come within the meaning and range of equivalency of the claims are therefore intended
to be embraced therein. In other words, it is contemplated to cover any and all modifications,
variations or equivalents that fall within the scope of the basic underlying principles
and whose essential attributes are claimed in this patent application. It will furthermore
be understood by the reader of this patent application that the words "comprising"
or "comprise" do not exclude other elements or steps, that the words "a" or "an" do
not exclude a plurality, and that a single element, such as a computer system, a processor,
or another integrated unit may fulfil the functions of several means recited in the
claims. Any reference signs in the claims shall not be construed as limiting the respective
claims concerned. The terms "first", "second", third", "a", "b", "c", and the like,
when used in the description or in the claims are introduced to distinguish between
similar elements or steps and are not necessarily describing a sequential or chronological
order. Similarly, the terms "top", "bottom", "over", "under", and the like are introduced
for descriptive purposes and not necessarily to denote relative positions. It is to
be understood that the terms so used are interchangeable under appropriate circumstances
and embodiments of the invention are capable of operating according to the present
invention in other sequences, or in orientations different from the one(s) described
or illustrated above.
1. A sports helmet (100) comprising a closable air inlet (120) for ventilation of the
wearer's head; wherein the air inlet comprises:
- blinds (102-104) movable between an open and closed position; and
- wherein, in the closed position, the blinds close the air inlet;
- wherein the blinds are positioned such that, in the open position, air (302) is
guided into the helmet along the blinds.
2. Sports helmet (100) according to claim 1 wherein, in the open position, the blinds
are positioned such that air (302) is guided into the helmet along the wearer's head.
3. Sports helmet (100) according to claim 1 or 2 wherein the helmet comprises an outside
surface (303) along which the air (301) is guided when the blinds (102-104) are in
the closed position; and wherein, in the open position, the blinds are in a tilted
position (112) with respect to the outside surface (303) of the helmet.
4. Sports helmet (100) according to any one of the preceding claims wherein the blinds
are rotatable (111) around a rotation axis between the closed and tilted position;
and wherein the rotation axis of each blind (101) is parallel to a tangent of the
blind and perpendicular to a direction (113) of the air flow (301) over the blind
(101) when the blind is in the closed position.
5. Sports helmet (100) according to claim 3 or 4 wherein the helmet comprises a front
(115) and back (116) portion thereby defining a front (117) and back (118) portion
of the blinds; and wherein the blind is rotatable around the front portion (117) such
that the blind is tilted inward the helmet when in the open position.
6. Sports helmet (100) according to any one of claims 3 to 5 wherein, in the open position,
the blinds are in a translated (110) position with respect to the outside surface
(303) of the helmet.
7. Sports helmet (100) according to any one of the preceding claims wherein the closable
air inlet comprises an engaging means (130) movable from a first position to a second
position arranged such that the blinds are moved between the open and closed position
when the engaging means is moved between the first and second position.
8. Sports helmet (100) according to claim 6 and 7; and wherein the blinds (101-104) are
pivotally mounted in the engaging means; and wherein the blinds are moved from the
closed position to the translated position when moving (110) the engaging means from
the first to second position; and wherein the helmet further comprises a guiding means
(119) arranged such that the blinds move from the closed position to the tilted position
by interaction with the guiding means when the engaging means moves from the first
to second position.
9. Sports helmet (100) according to any one of the preceding claims wherein the air inlet
comprises a cover (502) covering the blinds and comprising openings to guide the air
to the blinds.
10. Sports helmet (100) according to claim 9 as long as long as dependent on claim 7 or
8 wherein the engaging means is connected to the cover (502) and arranged such that
the engaging means is moved from the first to second position when the cover is moved
along the helmet's outer surface.
11. Sports helmet (100) according to claim 9 or 10 wherein the cover comprises an impact
absorbing structure.
12. Sports helmet (100) according to any one of the preceding claims further comprising
an actuation means (600) comprising an actuator (604) for moving the blinds from the
first to second position in an automated way.
13. Sports helmet (100) according to claim 12 wherein the actuation means (600) comprises
a temperature sensor (603).
14. Sports helmet (100) according to claim 12 or 13 wherein the actuator (604) comprises
a material which changes shape by a change in temperature arranged such that the blinds
move between the open and closed position depending on the temperature of the material.
15. Sports helmet (100) according to any one of claims 12 to 14 wherein the actuation
means comprises a sensor (602) for measuring the tilting of the helmet; and wherein
the helmet further comprises a processing unit (603) arranged to configure a position
of the blinds and thereby the air flow into the helmet based on the measured tilting.