U.S. patent application number 11/232283 was filed with the patent office on 2007-03-22 for fan-based cooler for head-protection gear.
Invention is credited to Nicholas J. Webb.
Application Number | 20070061946 11/232283 |
Document ID | / |
Family ID | 37882560 |
Filed Date | 2007-03-22 |
United States Patent
Application |
20070061946 |
Kind Code |
A1 |
Webb; Nicholas J. |
March 22, 2007 |
Fan-based cooler for head-protection gear
Abstract
A cooler accessory for use with a hard hat or other
head-protecting gear having a protective shell with a rim, the
accessory including a housing that is attachable to the protective
shell, flexible and pliable tubing that extends from the rigid
housing in a manner that allows for user control over position and
orientation of the tubing, and airflow supply means (e.g., an
electric fan assembly) for supplying a flow of air that passes
through the tubing and exits therefrom. During use, a portion of
the tubing is disposed below the rim of the protective shell for
directing the flow of air supplied by the airflow supply means
under the rim for injection toward space adjacent the user's body,
thereby cooling the user's body. Preferably, the tubing is
positioned such that airflow is injected into an air gap between
the user's head and the protective shell and over the user's head,
thereby actively cooling the user's head. In another aspect, parts
of the active cooling device (e.g., the housing or portions
thereof) can be integrally formed with the protective shell and rim
of the hard hat or other type of head-protection gear.
Inventors: |
Webb; Nicholas J.; (Redding,
CA) |
Correspondence
Address: |
GORDON & JACOBSON, P.C.
60 LONG RIDGE ROAD
SUITE 407
STAMFORD
CT
06902
US
|
Family ID: |
37882560 |
Appl. No.: |
11/232283 |
Filed: |
September 21, 2005 |
Current U.S.
Class: |
2/410 ; 2/209.13;
2/422 |
Current CPC
Class: |
A42B 3/286 20130101 |
Class at
Publication: |
002/410 ;
002/422; 002/209.13 |
International
Class: |
A42B 1/06 20060101
A42B001/06 |
Claims
1. A device for use with head-protection gear that includes a
protective shell with a rim, the device comprising: a housing that
is attachable to the protective shell; flexible and pliable tubing
that extends from the housing in a manner that enables a user to
adjust position and orientation of the tubing in order to control
the direction of the airflow that exits therefrom; and airflow
supply means, supported by the housing, for supplying a flow of air
that passes through the tubing and exits therefrom; wherein, during
use, a portion of the tubing is disposed below the rim of the
protective shell for directing the flow of air supplied by the
airflow supply means under the rim for injection toward space
adjacent the user's body, thereby cooling the user's body.
2. A device according to claim 1, wherein: the tubing is positioned
such that flow of air supplied by the airflow supply means is
injected into an air gap between the user's head and the protective
shell and over the user's head.
3. A device according to claim 1, wherein: the length of the tubing
is extendible.
4. A device according to claim 1, wherein: the housing defines an
interior air duct that extends from an opening to the tubing,
wherein the airflow supply means is mounted axially within the
interior air duct.
5. A device according to claim 3, further comprising: a removable
grill that covers the opening.
6. A device according to claim 1, further comprising: a battery
compartment that is supported by the housing and holds at least one
battery for powering the airflow supply means and at least one
user-manipulated switch and associated control circuitry that are
supported by the housing and operate to selectively couple the at
least one battery to the airflow supply means in response to user
manipulation of the at least one switch.
7. A device according to claim 6, further comprising: a first
user-manipulated switch cooperates with associated control
circuitry to operate in the following modes: i) a first mode
wherein airflow supply means is powered off; and ii) a second mode
wherein the airflow supply means is automatically cycled on/off for
predetermined on/off time periods.
8. A device according to claim 7, wherein: the first
user-manipulated switch cooperates with associated control
circuitry to operate in a third mode wherein the airflow supply
means is continuously powered on.
9. A device according to claim 8, wherein: the first
user-manipulated switch comprises a 3-position switch that is
disposed on a recessed surface of the housing and covered by a
movable door.
10. A device according to claim 7, further comprising: a second
user-manipulated switch cooperates with associated control
circuitry to operate in a fourth mode wherein the airflow supply
means is automatically powered on for a predetermined time period,
said fourth mode overriding the operations of the first and second
modes.
11. A device according to claim 10, wherein: the second
user-manipulated switch comprises a button switch that is disposed
on the exterior of the housing.
12. A device according to claim 11, wherein: the button switch
provides an ergonomic design that facilitates finger manipulation
by user's wearing gloves.
13. A device according to claim 6, wherein: the control circuitry
comprises a microcontroller that interfaces to switching circuitry
that selectively opens and closes a current path between the at
least one battery held in the battery compartment and the airflow
supply means, the operation of the microcontroller dictated by user
manipulation of the at least one switch.
14. A device according to claim 6, further comprising: a connector
that is supported by the housing and connects to an external power
source, the external power source selected from the group including
an AC/DC power converter, a DC/DC power converter, and a solar-cell
power source.
15. A device according to claim 14, wherein: the connector
interfaces to charging circuitry that charges the at least battery
held in the battery compartment with electrical energy supplied by
the external power source connected thereto.
16. A device according to claim 14, wherein: the connector
interfaces to control circuitry for selectively powering on the
airflow supply means with electrical energy supplied by the
external power source applied thereto.
17. A device according to claim 14, further comprising: means for
mounting the solar-cell power source on the housing.
18. A device according to claim 1, wherein: the housing includes a
curved base that generally follows the contour of a portion of the
exterior surface of the protective shell.
19. A device according to claim 18, further comprising: an insert
of flexible elastomeric material fixed to the curved base, wherein
the insert provides a cushion for mounting the housing onto the
exterior surface of the protective shell in a manner that
accommodates protective shells with varying shapes and sizes.
20. A device according to claim 19, further comprising: means for
detachably securing the curved base to the exterior surface of the
protective shell.
21. A device according to claim 1, wherein: said housing is
realized from a rigid plastic material.
22. A device according to claim 1, wherein: the airflow supply
means comprises one of an electric fan assembly, an air blower, a
centrifuge fan, and an air pump.
23. A device according to claim 1, wherein: the head-protection
gear is a hard hat.
24. A device according to claim 1, wherein: the head-protection
gear is one of a military helmet, motorcycle helmet, a helmet for
alpine skiing and/or snowboarding.
25. A method of cooling a user wearing head-protection gear that
has a protective shell with a rim, the method comprising: attaching
a device to the protective shell, the device including a housing,
flexible and pliable tubing that extends from the housing in a
manner that enables a user to adjust position and orientation of
the tubing in order to control the direction of the airflow that
exits therefrom, and airflow supply means supported by the housing
for supplying a flow of air that passes through the tubing and
exits therefrom; adjusting the position of the tubing such that a
portion of the tubing is disposed below the rim of the protective
shell for directing the flow of air supplied by the airflow supply
means under the rim for injection towards space adjacent the user's
head, thereby cooling the user's body; and activating the airflow
supply means to produce a flow of air that is directed under the
rim and injected toward space adjacent the user's head, thereby
cooling the user's body the user's head.
26. A method according to claim 25, further comprising:
manipulating the tubing to adjust its length.
27. A method according to claim 25, further comprising: providing
the device with a battery compartment; and loading the battery
compartment with at least one battery for powering the airflow
supply means.
28. A method according to claim 27, further comprising: providing
the device with at least one user-manipulated switch and associated
control circuitry that operate to selectively couple the at least
one battery to the airflow supply means in response to user
manipulation of the at least one switch; manipulating the at least
one switch for activation of the electric fan assembly.
29. A method according to claim 28, further comprising: providing
the device with a first user-manipulated switch that cooperates
with associated control circuitry to operate in the following
modes: i) a first mode wherein the airflow supply means is powered
off; and ii) a second mode wherein the airflow supply means is
automatically cycled on/off for predetermined on/off time
periods.
30. A method according to claim 29, wherein: the first
user-manipulated switch cooperates with associated control
circuitry to operate in a third mode wherein the airflow supply
means is continuously powered on.
31. A method according to claim 29, wherein: the first
user-manipulated switch comprises a 3-position switch that is
disposed on a recessed surface of the housing and covered by a
movable door.
32. A method according to claim 29, further comprising: providing
the device with a second user-manipulated switch that cooperates
with associated control circuitry to operate in a fourth mode
wherein the airflow supply means is automatically powered on for a
predetermined time period, said fourth mode overriding the
operations of the first and second modes.
33. A method according to claim 32, wherein: the second
user-manipulated switch comprises a button switch that is disposed
on the exterior of the housing.
34. A method according to claim 28, wherein: the control circuitry
comprises a microcontroller that interfaces to switching circuitry
that selectively opens and closes a current path between the at
least one battery held in the battery compartment and the airflow
supply means, the operation of the microcontroller dictated by user
manipulation of the at least one switch.
35. A method according to claim 27, further comprising: providing
the device with a connector that is supported by the housing and
connects to an external power source, the external power source
selected from the group including an AC/DC power converter, a DC/DC
power converter, and a solar-cell power source.
36. A method according to claim 35, wherein: the connector
interfaces to charging circuitry that charges the at least battery
held in the battery compartment with electrical energy supplied by
the external power source connected thereto.
37. A method according to claim 35, wherein: the connector
interfaces to control circuitry for selectively powering on the
airflow supply means with electrical energy supplied by the
external power source applied thereto.
38. A method according to claim 35, further comprising: connecting
the solar-cell power source to the connector.
39. A method according to claim 35, further comprising: mounting
the solar-cell power source onto the housing of the device.
40. A method according to claim 25, further comprising: providing
the housing of the device with a curved base that generally follows
the contour of a portion of the exterior surface of the protective
shell; and detachably mounting the curved base to an exterior
surface of the protective shell.
41. A method according to claim 40, further comprising: providing
the housing of the device with an insert of flexible elastomeric
material fixed to the curved base, wherein the insert provides a
cushion for mounting the housing onto the exterior surface of the
protective shell in a manner that accommodates protective shells
with varying shapes and sizes.
42. A method according to claim 40, wherein: the device is
detachably mounted on the rear portion of the protective shell.
43. A method according to claim 42, wherein: the tubing of the
device is positioned such that airflow is injected into an air gap
between the user's head and the protective shell and over the
user's head, thereby cooling the user's head.
44. A method according to claim 25, wherein: the airflow supply
means comprises one of an electric fan assembly, an air blower, a
centrifuge fan, and an air pump.
45. A method according to claim 25, wherein: the head-protection
gear is a hard hat.
46. A method according to claim 25, wherein: the head-protection
gear is one of a military helmet, motorcycle helmet, a helmet for
alpine skiing and/or snowboarding.
47. A head-protection apparatus comprising: a protective shell with
a rim; a housing with portions that are attachable to, or
integrally formed with, the protective shell; flexible and pliable
tubing that extends from the rigid housing in a manner that enables
a user to adjust position and orientation of the tubing in order to
control the direction of the airflow that exits therefrom; and
airflow supply means supported by the housing for supplying a flow
of air that passes through the tubing and exits therefrom; wherein,
during use, a portion of the tubing is disposed below the rim of
the protective shell for directing the flow of air supplied by the
electric fan assembly under the rim for injection toward space
adjacent the user's body, thereby cooling the user's body.
48. A head-protection apparatus according to claim 47, wherein: the
tubing is positioned such that flow of air supplied by the airflow
supply means is injected into an air gap between the user's head
and the protective shell and over the user's head.
49. A head-protection apparatus according to claim 47, wherein: the
length of the tubing is extendible.
50. A head-protection apparatus according to claim 47, wherein: the
housing defines an interior air duct that extends from an opening
to the tubing, wherein the airflow supply means is mounted axially
within the interior air duct.
51. A head-protection apparatus according to claim 47, further
comprising: a battery compartment that is supported by the housing
and holds at least one battery for powering the airflow supply
means; and at least one user-manipulated switch and associated
control circuitry that are supported by the housing and operate to
selectively couple the at least one battery to the airflow supply
means in response to user manipulation of the at least one
switch.
52. A head-protection apparatus according to claim 47, wherein:
said housing is realized from a rigid plastic material.
53. A head-protection apparatus according to claim 47, wherein: the
airflow supply means comprises one of an electric fan assembly, an
air blower, a centrifuge fan, and an air pump.
54. A head-protection apparatus according to claim 47, which is
realized as a hard hat.
55. A head-protection apparatus according to claim 47, which is
realized as one of a military helmet, motorcycle helmet, a helmet
for alpine skiing and/or snowboarding.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] This invention relates broadly to hard hats for protecting
the heads of users in dangerous environments, such as construction
sites, mines, industrial environments (e.g., chemical plants,
assembly plants, steel mills, lumber mills), forestry and other
tree cutting and pruning environments, military helmets, motorcycle
helmets, helmets for alpine skiing and/or snowboarding, and other
head-protection gear that employ a rigid head-protecting shell.
More particularly, the invention relates to mechanisms that are
secured to (or part of) the protective shell of a hard hat and
operate to cool the user.
[0003] 2. State of the Art
[0004] Environments involving high temperatures, radiant heat
sources, high humidity, direct physical contact with hot objects,
or strenuous physical activities have a high potential for inducing
heat stress in individuals that work in such environments. Such
environments include iron and steel foundries, brick-firing and
ceramic plants, glass products facilities, rubber products
facilities, electrical utilities (particularly boiler rooms),
bakeries, confectioneries, commercial kitchens, laundries, food
canneries, chemical plants, mining sites, smelters and steam
tunnels.
[0005] Outdoor operations conducted in hot weather, such as
construction, forestry and lumber mills, refining, asbestos
removal, and hazardous waste site activities, especially those that
require workers to wear semi-permeable or impermeable clothing are
also likely to cause heat stress among exposed workers.
[0006] In many of these environments, workers wear hard hats that
protect the users' heads from falling debris and other potential
hazards. However, in hot weather, hard hats provide a "greenhouse"
effect where the humidity caused by body perspiration about the
head and neck builds up under the hard hat, thereby thwarting the
body's own evaporative cooling system. Some leading hard hat
manufactures have introduced small air vents similar to the concept
disclosed in U.S. Pat. No. 6,170,090 to Minor. However, these small
vents provide minimal to no cooling effect. There have been many
hard hat designs that actively cool the user by blowing air over
the head. Such a design takes advantage of the body's own
evaporative cooling system and enhances it with the cooling
properties of wind chill. See U.S. Pat. No. Re. 36,242 to Apisdorf,
U.S. Pat. No. 3,813,696 to Yeager, U.S. Pat. No. 3,881,198 to
Waters, U.S. Pat. No. 3,881,478 to Rosendahl et al., U.S. Pat. No.
4,680,815 to Hirsch et al., U.S. Pat. No. 4,893,356 to Waters, U.S.
Pat. No. 5,561,862 to Flores, Sr., U.S. Pat. No. 6,122,773 to Katz,
and U.S. Pat. No. 6,760,925 to Maxwell. However, these designs are
disadvantageous in that they require modification (e.g.,
thru-holes) to the protective shell of the hard hat and thus risk
compromising the structural integrity of the protective shell. Some
standards bodies such as the American National Standards Institute
(ANSI) also forbid modification of the hard hat by drilling holes.
Moreover, the designs suffer from other limitations including high
costs, the inability to remove the active cooling mechanism from
the hard hat, the inability to secure the active cooling mechanism
to hard hats of varying size, the use of materials that are
unsuitable for rugged high-impact environments, and the lack of
effective user control over the active cooling function.
[0007] Thus, there remains a need in the art to provide an active
cooling device for use with a hard hat that does not require
modification to the protective shell of the hard hat (and thus does
not risk compromising the structural integrity of the hard hat).
Moreover, there remains a need in the art for such an active
cooling device that is inexpensive, preferably removable from the
hard hat, capable of being added to hard hats of varying size, uses
materials that are suitable for rugged high-impact environments,
and affords effective user control over the active cooling
function.
SUMMARY OF THE INVENTION
[0008] It is therefore an object of the invention to provide an
active cooling device for use with a hard hat that does not require
modification to the protective shell of the hard hat (and thus does
not risk compromising the structural integrity of the hard
hat).
[0009] It is another object of the invention to provide such an
active cooling device that is inexpensive.
[0010] It is a further object of the invention to provide such an
active cooling device that is removable from the hard hat.
[0011] It is also an object of the invention to provide such an
active cooling device that is capable of being added to hard hats
of varying size.
[0012] It is an additional object of the invention to provide such
an active cooling device that is realized from materials that are
suitable for rugged high-impact environments.
[0013] It is still another object of the invention to provide such
an active cooling device that affords effective user control over
the cool function of the device.
[0014] In accord with these objects, which will be discussed in
detail below, an active cooler accessory is provided for use with a
hard hat or other head-protecting gear having a protective shell
with a rim. The accessory includes a housing that is attachable to
the protective shell, flexible and pliable tubing that extends from
the housing in a manner that allows for user control over position
and orientation of the tubing, and airflow supply means (e.g., an
electric fan assembly) for supplying a flow of air that passes
through the tubing and exits therefrom. During use, a portion of
the tubing is disposed below the rim of the protective shell for
directing the flow of air supplied by the airflow supply means
under the rim for injection toward space adjacent the user's body,
thereby cooling the user's body. Preferably, the tubing is
positioned such that airflow is injected into an air gap between
the user's head and the protective shell and over the user's head,
thereby actively cooling the user's head. Preferably, the housing
supports a battery compartment and at least one user-manipulated
switch and associated control circuitry that operate to selectively
couple at least one battery held within the battery compartment to
the electric fan assembly in response to user manipulation of the
at least one switch.
[0015] It will be appreciated that the cooling airflow provided by
the accessory device can be directed such that it flows over the
user's head, which works in conjunction with the body's own
evaporative cooling system to significantly reduce the heat and
humidity experienced by the user and thus results in a significant
increase in the comfort of the user. Such cooling also reduces the
exposure to work related heat exhaustion, potential serious
heatstroke and reduced productivity.
[0016] According to one embodiment of the invention, a first switch
(e.g., 3-position switch) cooperates with control circuitry to
operate in each one of the following modes: i) a first mode wherein
airflow supply means is powered off; ii) a second mode wherein the
airflow supply means is automatically cycled on/off for
predetermined on/off time periods; and iii) a third mode wherein
the airflow supply means is continuously powered on. A second
switch (e.g., larger size push button switch) cooperates with the
control circuitry to operate in a fourth mode wherein the airflow
supply means is automatically powered on for a predetermined time
period, with the fourth mode overriding the operations of the first
and second modes.
[0017] According to another embodiment of the invention, the
housing supports one or more connectors that connect to external
power source(s) (e.g., external AC/DC power converter (outlet
charger), external DC/DC power converter (automobile cigarette
lighter charger), external solar-cell power converter) for charging
the battery(ies) that are held in the battery compartment of the
housing, and possibly for powering the airflow supply means of the
device for use.
[0018] According to yet another embodiment of the invention, the
housing includes a curved base that generally follows the contour
of an exterior portion of the protective shell with a flexible
insert cushion fixed thereto. The tubing is extendible along its
length. These features allow the accessory to be secured to hard
hats of varying size and shape.
[0019] In another aspect of the present invention, parts of the
active cooling device (e.g., the housing or portions thereof can be
integrally formed with the protective shell and rim of the hard
hat.
[0020] Additional objects and advantages of the invention will
become apparent to those skilled in the art upon reference to the
detailed description taken in conjunction with the provided
figures.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] FIG. 1 is a perspective view of a cooling accessory secured
to a hard hat in accordance with the present invention.
[0022] FIG. 2A is a perspective view of the cooling accessory of
FIG. 1.
[0023] FIG. 2B is an exploded view of the cooling accessory of FIG.
1.
[0024] FIG. 3 is a side view of the cooling accessory of FIG.
1.
[0025] FIG. 4 is an internal view of the electric fan assembly of
the accessory of FIG. 1 and the airflow generated thereby for
cooling purposes.
[0026] FIG. 5 is a blown-up view of a recessed compartment in the
housing of the accessory of FIG. 1, which supports a user control
switch and two connector ports for connection to external power
sources.
[0027] FIG. 6 is a schematic diagram of exemplary control circuitry
that is supported by the housing of FIG. 1 and provides for smart
activation of the electric fan assembly in accordance with user
input.
[0028] FIG. 7 is a perspective view of the accessory of FIG. 1,
with an external solar-cell power source mounted onto its
housing.
[0029] FIGS. 8A-8C are different views of the accessory of FIG. 1,
showing exemplary dimensions for different parts of the
accessory.
[0030] FIG. 8D is a view of the accessory of FIG. 7, showing
exemplary dimensions for the external solar-cell power
generator.
[0031] FIGS. 9A and 9B are different perspective views of an
alternate embodiment of the present invention wherein parts of the
active cooling device are integrally formed with the protective
shell and rim of a hard hat.
[0032] FIG. 10 is a side view of another embodiment of a cooling
accessory that is secured to a hard hat in accordance with the
present invention.
DETAILED DESCRIPTION
[0033] The term "hard hat" as used herein is meant to include not
only the specific designs shown, but also include other types of
head-protecting safety hats for dangerous environments such as
construction sites, mines, industrial environments (e.g., chemical
plants, assembly plants, steel mills, lumber mills), forestry and
other tree cutting and pruning environments, miner's hats,
protective hats for industrial applications, protective hats for
lumbering and tree pruning applications, military helmets,
motorcycle helmets, helmets for alpine skiing and/or snowboarding,
and other head-protection gear that employ a rigid head-protecting
shell.
[0034] Turning now to FIG. 1, an exemplary hard hat 10 includes a
molded, hard plastic protective shell 12 with a rim 14 surrounding
a domed-shaped head cover portion 16 that defines a head-receiving
cavity 18 therein. A head support harness (not shown) is affixed to
the interior surface of the dome-shaped head cover portion 16 and
is disposed within the head-receiving cavity 18. The head-support
harness interfaces to the user's head and supports the shell 12
above the user's head such that an air gap exists therebetween. A
cooling accessory 21 is affixed to the exterior surface of the
shell 12, preferably to the rear portion of the shell 12 as
shown.
[0035] As best shown in FIGS. 2A, 2B and 3, the cooling accessory
21 includes a rigid plastic housing 23 preferably realized from
three distinct housing parts 23A, 23B, 23C (FIG. 2B). The housing
part 25C has a curved base 25 that generally follows the contour of
the domed-shaped portion 16 of the protective shell 12. In the
preferred embodiment, the housing parts 23A, 23B, 23C are realized
from a lightweight material suitable for high-impact applications
such as an acrylonitrile-butadiene-styrene (ABS) copolymers or
polypropylene or other suitable plastic suitable for high impact
applications, carbon fiber, Kevlar, or other high impact
material.
[0036] As best shown in the exploded view of FIG. 2B, a flexible
insert 27 of elastomeric material (such as rubber or neoprene) is
fixed to the base 25 preferably with an adhesive layer. One or more
hook-and-loop fastener pads (not shown) may be adhesively affixed
to the insert 27 preferably by the user and then secured to the
protective shell 12 to locate the accessory 21 on the exterior
surface of the protective shell 12 and then remove it if desired.
Alternatively, the base 25 and/or the insert 27 may be adhesively
fixed to the protective shell 12. The insert 27 provides a cushion
for mounting the housing 23 onto the exterior surface of the
protective shell 12 in a manner that accommodates protective shells
with varying shapes and sizes (e.g., varying radii of curvature).
This allows the accessory 21 to be mounted on hard hats with
varying shapes and sizes. Rubber trim 28 may surround the edge of
the curved base 25 in order to hide a gap that may exist between
the curved base 25 and the protective shell 12. The rubber trim 28
also keeps dust and debris away from the curved base 25 and the
interface between the base 25 and the protective shell 12.
[0037] As best shown in FIG. 2B and FIG. 4, the housing part 23A
defines an opening 29 that leads to an air duct 31 within the
housing part 23B. A grille 33 covers the opening 29. An electric
fan assembly 35, comprising a fan blade 37 driven by an electric
motor 39, is mounted axially within the air duct 31. A hose 41 is
coupled to the bottom of the housing part 23C in fluid
communication with air duct 31. The electric fan assembly 35, when
powered on, operates to draw air into the opening 29 and through
the air duct 31 and hose 41 where it exits from the end port 43 of
the hose. The grille 33 may be removeable by the user such that the
user can access the fan blade 37 (and possibly the electric motor
39) for cleaning and maintenance as required. In the preferred
embodiment, the air duct 31 and the electric fan assembly 35 are
adapted to produce airflow through and out the hose 41 in a range
between 14 to 16 cfm. The hose 41 is realized from a flexible and
pliable construction that enables the user to adjust the position
and orientation of the end port 43 in order to control the
direction of the airflow that exits therefrom as desired. Moreover,
the construction of the hose 41 preferably allows for extension of
the hose 31 along its length to further provide greater flexibility
in user positioning of the end port 43. In the preferred
embodiment, the hose 41 is constructed of corrugated rubber,
silicone or poly-elastomeric material and has a length that can
vary between 50 mm and 170 mm. The user extends the hose 41 by
applying an axially pulling force (e.g., away from the housing) to
a desired section of the hose 41. The user shortens the hose 41 by
applying an axial pushing force (e.g., toward the housing) to a
desired section of hose. The lengthwise extendibility of the hose
41 also allows the device to be used on hard hats with different
rim sizes (e.g., no-brim hard hats, short-brim hard hats, long-brim
hats, and possibly Western-style hard hats).
[0038] During use, the air duct 31 is positioned substantially
orthogonal relative to the plane defined by the rim 14 as best
shown in FIG. 1. In this manner, the air duct 31 and electric fan
assembly 35 are typically disposed in a substantially vertical
position during use. A portion of the flexible hose 41 is
positioned under the rim 14 such that the airflow produced by the
electric fan assembly 35 flows under the rim 14 of the hard hat 10.
The end port 43 of the hose is positioned such that airflow exiting
therefrom is directed to flow towards or around a part of the
user's body for cooling purposes. Preferably, the end port 43 of
the hose is positioned such the exiting airflow is injected upward
from the rear of the hard hat 10 into the air gap between the
user's head and the protective shell 12 and up over the head where
it is then exhausted below the front of the hard hat 10. In this
configuration, the airflow passes over the back, top and front of
the user's head, which provides a maximal cooling effect. Note that
the tube 41 generally has a u-shape along its length in order to
guide the airflow under the rim 14 of the hard hat 10 and eject it
upward into the air gap between the user's head and the protective
shell 12. Alternatively, the end port of the host can be positioned
such that the airflow is directed towards or around other parts of
the head (e.g., the base of the head), the neck, or other part(s)
of the body.
[0039] The housing 23 includes a battery compartment 38 (not shown)
that holds one or more batteries that supply electrical power to
the electric motor 39 of the fan assembly 35. The housing part 23C
also supports a printed circuit board (FIG. 6) mounted therein that
includes a microcontroller 51 and associated circuitry. The
microcontroller 51 interfaces to switching circuitry 53 that
selectively closes and opens one or more current paths that allow
the battery(ies) 38 to power on and off the electric motor 39 of
the fan assembly 35. The microcontroller 51 also interfaces to a
set of one or more user-operated switches (e.g., two switches 45A
and 45B--see FIG. 6) that are supported by the housing 23. The one
or more user-operated switches allow the user to control the
operation of the electric motor 39 to thereby activate the cooling
fan function provided by the device.
[0040] In the preferred embodiment, two switches 45A and 45B are
used. As best shown in FIG. 5, the first switch 45A is a
three-position switch that is disposed in a recessed compartment 47
of the housing and accessible by a removable cover 49 (FIG. 1). In
this configuration, the first switch 45A is protected from direct
impact forces (which can be experienced if the hard hat 10 is
dropped or otherwise impacted) as well as from direct environmental
factors (e.g., rain, snow, dust, etc). The second switch 45B, which
is preferably realized as an ergonomically designed larger-size
button switch preferably with a diameter greater than 15 mm (and
most preferably in a range between 20 mm and 30 mm in a range) as
best shown in FIGS. 1-3 and 8B, is disposed on the exterior of the
housing 23 for quick user access. In this configuration, the second
switch 45B is specifically designed to withstand a degree of direct
impact forces (which can be experienced if the hard hat 10 is
dropped or otherwise impacted) as well as a degree of direct
environmental factors (e.g., rain, snow, dust, etc). The second
switch 45B also preferably provides tactile feedback that enables
the user to operate the switch 45B with work gloves that are
commonly used in such dangerous environments. In the preferred
embodiment, the second switch 4
[0041] As shown in the schematic diagram of FIG. 6, the fist switch
45A and second switch 45B interface to the microcontroller 51, for
example a PIC 16F630 microcontroller, which is commercially
available from Microchip Technology, Inc. of Chandler, Ariz. The
microcontroller 51 also interfaces to a switching circuit 53 (e.g.,
a field-effect transistor Q1) that selectively opens and closes a
current path (e.g., the ground path between the H4 terminal of the
electric motor 39 and ground potential) that allows the
battery(ies) 38 to power on and off the electric motor 39.
[0042] The first switch 45A cooperates with the microcontroller 51
to carry out three different operations modes as follows: [0043] i)
".smallcircle." position--Off Mode: the switching circuitry 53 is
controlled so that electric motor 39 is powered off--the transistor
Q1 is switched OFF so that the ground current path is inactive);
[0044] ii) "A" position--Intermittent Mode: the switching circuitry
53 is controlled so that the electric motor is automatically cycled
on/off for predetermined on/off time periods (e.g., on for one
minute and then off for four minutes)--the transistor Q1 is
automatically cycled on/off for predetermined on/off time periods
so that the ground current path is cycled on/off; [0045] iii)
".circle-solid." position--Continuous Mode: the switching circuitry
53 is controlled so that electric motor 39 is continuously powered
ON--the transistor Q1 is switched ON so that the ground current
path is continuously active. Preferably, the power capacity of the
battery(ies) held in the battery compartment, the power consumption
characteristics of the electric motor 39 and the associated control
circuitry, and the predetermined ON/OFF time periods of the
Intermittent mode are adapted such that the electric motor 39 can
operate in the Intermittent mode for an 8 to 10 hour time period.
In this configuration, the Intermittent mode is advantageous
because the device can be used to cool the user for an entire work
day (or a substantial part of a long work day) on a single battery
charge. The Intermittent mode has other advantages. More
particularly, during the OFF time periods, heat and moisture will
typically build up under the protective shell 12 and cause the user
to perspire. In the ON mode, the air blown over the head will
enhance the evaporative-based cooling provided by such perspiration
for an improved cooling effect.
[0046] The second switch 45B cooperates with the microcontroller 51
to carry out a "Fast-Blast" mode wherein the switching circuitry 53
is controlled to power ON the electric motor 39 for a predetermined
time period (e.g., two minutes)--the transistor Q1 is automatically
cycled on for the predetermined time period so that the ground
current path is activated for the predetermined time period. In
such operations, the "Fast-Blast" mode overrides the "OFF" and
"Intermittent" modes such that the "Fast-Blast" mode takes
precedence over the control of the switching circuitry 53 (e.g.,
transistor Q1) and governs the operation of the electric motor 39.
In the preferred embodiment, the "Fast-Blast" switch 45B
[0047] Referring back to FIG. 5, the housing part 23B preferably
includes a first connector port 51A for connecting to an external
AC/DC power converter (outlet charger) or to an external DC/DC
power converter (automobile cigarette lighter charger) (not shown)
and a second connector port 51B for connecting to an external
solar-cell power generator 53 (FIG. 7). Alternatively, these two
external power sources may be connected to the same connector. The
connector port(s) are preferably located in the same recess as the
first switch 45A as shown for protection against direct impact and
environmental factors. The printed circuit board supported within
the housing also includes charging circuitry, operably coupled
between the connector port(s) and the battery(ies) held in the
battery compartment, that operates to charge the battery(ies) using
the electrical power signal(s) supplied thereto by the external
power source. The external power sources (e.g., the solar-cell
power generator 53) may also be used in conjunction with the
battery(ies) to supply power to the electric motor 39 of the
electric fan assembly during use. Alternatively, the external power
sources (e.g., the solar-cell power generator 53) may be as a
substitute for the battery(ies) to thereby supply power to the
electric motor 39 of the electric fan assembly during use, without
charging the batteries. In preferred embodiment, the external
solar-cell power generator 53 is part of a unitary construction
23A' that is removably secured to the top of housing part 23C about
the opening 29 where it is positioned above the curved base 25 as
shown in FIG. 7. A wire (not shown) connects the solar-cell power
generator 53 to the second connector port 51B for charging/powering
the device.
[0048] The dimensions of an exemplary embodiment of the cooling
accessory of the present invention is shown in FIGS. 8A-8C. The
overall height of the housing 23 is on the order of 112 mm. The
diameter of the housing part 23C that defines the air duct 31 is on
the order of 64 mm in diameter. The width of the curved base 25 is
on the order of 82 mm. In another exemplary embodiment shown in
FIG. 8D, the housing part 23A' is extended above the curved base 25
for mounting an external solar-cell power generator 53 thereon as
shown in FIG. 7. In this embodiment, the external solar-cell power
generator 53 is on the order of 94 inches wide and 54 inches in
length.
[0049] In an alternate embodiment shown in FIGS. 9A and 9B, the
housing 23' (or parts thereof) of the active cooling device 21' is
integrally formed (preferably by injection molding) with the
protective shell 12' and rim 14 of a hard hat 10'. In this
alternate embodiment, means for securing the housing of the cooling
device to the hard hat are omitted and the active cooling device
21' includes the same functional elements and structural elements
as the accessory 21 as described above, and operates in the same
manner as the accessory 21 as set forth above.
[0050] In yet another alternate embodiment shown in FIG. 10, the
opening 29'' defined by the housing parts 23A'' and 23C'' of the
active cooling device 21'' is angled downward at an angle
.alpha.+90.degree. relative to the central axis of the air duct
31'' as it extends away from the top of the curved base portion 25.
In the illustrative embodiment shown, the angle a is on the order
of 20.degree.. It is contemplated that the angle a may have another
value between 0.degree. and 30.degree., or possibly a larger angle
value. Moreover, in this alternate embodiment, the lower housing
23B'' and the hose 41'' are realized as a single unitary plastic
part that is formed by injection molding of plastic. The active
cooling device 21'' includes the same functional elements and
structural elements as the accessory 21 as described above, and
operates in the same manner as the accessory 21 as set forth
above.
[0051] Advantageously, the cooling airflow provided by the active
cooling device of the present invention can be directed such that
it flows over the user's head, which significantly reduces the heat
and humidity experienced by the user and greatly enhances the
body's evaporative cooling mechanism (perspiration) and thus
results in a significant increase in the comfort of the user. Such
cooling also reduces the exposure to work related heat exhaustion,
potential serious heatstroke while improving worker concentration
and productivity. Moreover, such cooling is consistent with the
Occupational Safety & Health Administration's guidelines for
methods for controlling and preventing heat related illness. The
housing also provides crush absorption to absorb shock. Finally,
the device's low cost and durable construction affords exceptional
return on investment.
[0052] In alternate embodiments, the housing of the device may be
realized from a lightweight, low-cost foam material (or possibly
some other material). Such foam material provides additional crush
absorption to absorb shock beyond that provided by a rigid plastic
housing.
[0053] There have been described and illustrated herein several
embodiments of a fan-based cooler accessory for a hard hat and
related methods of operation. While particular embodiments of the
invention have been described, it is not intended that the
invention be limited thereto, as it is intended that the invention
be as broad in scope as the art will allow and that the
specification be read likewise. Thus, while particular
configurations and materials have been disclosed, it will be
appreciated that other configurations and materials can be used as
well. Moreover, while the device described above employs an
electric fan assembly to actively generating a supply of airflow,
other air moving mechanisms (such as an air blower, centrifuge fan
or air pump) can also be used. Also, while particular mechanisms
for securing the device to the hard hat have been disclosed, other
fixation mechanisms that do not rely on drilling, such as suction
cups, permanent adhesives, etc. can be used. In some applications,
fixation means (e.g., screws, rivets) that employ holes drilled
through the protective shell of the hard hat may be used. In
addition, while particular control schemes and electronic control
circuitry have been disclosed, it will be understood that other
control schemes and other electronic control circuitry can be used.
It will therefore be appreciated by those skilled in the art that
yet other modifications could be made to the provided invention
without deviating from its spirit and scope as claimed.
* * * * *