U.S. patent application number 17/311017 was filed with the patent office on 2022-01-20 for portable thermoelectric unit to adjust body's microclimate.
This patent application is currently assigned to POLITECNICO DI TORINO. The applicant listed for this patent is POLITECNICO DI TORINO, SPARCO S.P.A.. Invention is credited to Angelo BARDASCINO, Giorgio DE PASQUALE.
Application Number | 20220018579 17/311017 |
Document ID | / |
Family ID | 1000005930368 |
Filed Date | 2022-01-20 |
United States Patent
Application |
20220018579 |
Kind Code |
A1 |
DE PASQUALE; Giorgio ; et
al. |
January 20, 2022 |
PORTABLE THERMOELECTRIC UNIT TO ADJUST BODY'S MICROCLIMATE
Abstract
A portable thermoelectric unit has a face towards the user's
body. The unit includes at least one flexible layer containing a
non-woven fabric or a fabric and/or a polymeric membrane facing the
body; a casing having a thermally active area and fixed to a distal
face of the layer opposite the face so that the area is in thermal
exchange with the layer towards the body; a thermoelectric heat
pump device housed in the casing and configured to generate or
absorb heat through the area and the layer; a fan housed in the
casing and next to the device; a channel in the casing next to the
device to receive an air flow generated by the fan in heat exchange
with the device and to guide the air flow towards a distal opening
from the fan; and a heat exchanger connected to the device on the
opposite side of the area to receive the air flow towards the
channel.
Inventors: |
DE PASQUALE; Giorgio;
(Torino, IT) ; BARDASCINO; Angelo; (Volpiano
(Torino), IT) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
POLITECNICO DI TORINO
SPARCO S.P.A. |
Torino
Volpiano (Torino) |
|
IT
IT |
|
|
Assignee: |
POLITECNICO DI TORINO
Torino
IT
SPARCO S.P.A.
Volpiano (Torino)
IT
|
Family ID: |
1000005930368 |
Appl. No.: |
17/311017 |
Filed: |
December 2, 2019 |
PCT Filed: |
December 2, 2019 |
PCT NO: |
PCT/IB2019/060352 |
371 Date: |
June 4, 2021 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
F25D 2400/26 20130101;
F25B 2321/0251 20130101; F25B 2321/023 20130101; F25B 21/04
20130101 |
International
Class: |
F25B 21/04 20060101
F25B021/04 |
Foreign Application Data
Date |
Code |
Application Number |
Dec 6, 2018 |
IT |
102018000010879 |
Claims
1: A portable thermoelectric unit having a face towards the body of
a user, the unit comprising: at least one flexible layer comprising
a non-woven fabric or a fabric and/or a polymeric membrane facing
the body; a casing having a thermally active area and fixed to a
distal face of the layer opposite the face towards the body so that
the thermally active area is in thermal exchange with the layer
towards the body; a thermoelectric heat pump device housed in the
casing and configured to generate or absorb heat through the
thermally active area and the layer; a fan housed in the casing and
next to the thermoelectric device; a channel in the casing next to
the thermoelectric device to receive a flow of air generated by the
fan in heat exchange with the thermoelectric device and to guide
the air flow towards a distal opening from the fan; a heat
exchanger connected to the thermoelectric device on the opposite
side of the thermally active area so as to receive the air flow
generated by the fan towards the channel, wherein, between the
thermally active area and the heat exchanger, only the heat
exchanger is exposed to the air flow.
2: The unit according to claim 1, wherein the thermoelectric device
adheres to the thermally active area.
3: The unit according to claim 1, wherein the thermally active area
comprises a window facing a face of the thermoelectric device
opposed to the heat exchanger.
4: The unit according to claim 1, wherein the casing is
substantially flattened and oblong so as to keep the fan, the heat
exchanger and an intake of the channel arranged side by side and
substantially aligned.
5: The unit according to claim 1, wherein the casing is soft and
elastically hand deformable and comprises a polymeric material
based on silicone or thermoplastic polyurethane.
6: The unit according to claim 5, wherein the polymeric material
comprises an isocyanate and a polyol.
7: The unit according to claim 5, wherein the channel comprises one
or more spacing projections arranged in one or more cross sections
of the channel to avoid or limit collapses of the channel in case
of applied loads on the housing.
8: The unit according to claim 1, wherein the casing defines an
intake opening to supply the fan, and the intake opening and the
distal opening are arranged on a face of the housing opposite to
the thermally active area.
9: A heat-resistant garment, comprising the unit according to claim
1, wherein the at least one flexible layer faces the body of the
user and the casing is placed in a filling of the garment.
10: The garment according to claim 9, which is a suit for an
automobile driver.
Description
FIELD OF INVENTION
[0001] The present invention refers to a thermoelectric portable
unit to increase the comfort of a user, according to a non-limiting
example, in clothing to withstand high temperatures, such as a fire
retardant suit for an automobile driver.
STATE OF THE ART
[0002] A user can be exposed to extreme climatic conditions and the
need is felt to provide a portable aid that allows to reduce the
impact of these conditions both for heating and for cooling the
user according to the situation. It is known to provide heating
devices, but the possibilities of providing cooling are less
common.
[0003] US-2001/0007952 describes a garment provided with a
thermoelectric module having a first and a second heat exchange
face both exposed to a relative forced air flow within the same
environment, delimited by an internal lining on one side and one
outer layer of the garment on the other. In this configuration,
during operation, the two heat exchange faces initially assume
different temperatures for the purpose of heat exchange with the
person wearing the garment. However, after a relatively short
transient, these faces both go to an intermediate temperature, thus
ceasing to define a temperature regulation action for the person
wearing the garment.
SCOPES AND SUMMARY OF THE INVENTION
[0004] The scope of the present invention is to provide a portable
thermoelectric unit for regulating over time the temperature
perceived by the user and is, at the same time, efficient and
compact.
[0005] The scope of the present invention is achieved by a portable
thermoelectric unit having a face towards the body comprising:
[0006] at least one flexible layer comprising a non-woven fabric or
fabric and/or a polymeric membrane facing the body; [0007] a casing
having a thermally active area and fixed to a distal face of the
layer opposite the face towards the body so that the thermally
active area is in heat exchange with the layer; [0008] a
thermoelectric heat pump device housed in the casing and configured
to generate or absorb heat through the thermally active area and
the layer; [0009] a fan housed in the casing and on a side of the
thermoelectric device; [0010] a channel in the casing on a side of
the thermoelectric device to receive through the thermoelectric
device an air flow generated by the fan and guide said flow towards
an opening distal from the fan; [0011] a heat exchanger connected
to the thermoelectric device on the opposite side of the thermally
active area so as to receive the air flow generated by the fan
towards the channel, wherein, between the thermally active area and
the heat exchanger, only the heat exchanger is exposed to the air
flow.
[0012] This unit is compact, light and offers effective heat
exchange with the user towards the thermally active area. In fact,
only the heat exchanger is exposed to the air flow in order to
increase the thermal gradient of the thermoelectric device with the
thermally active area. In addition, efficiency is increased because
the fan and the distal opening are spaced from each other via the
channel that leads the air from the heat sink to the distal
opening. In this way the air exhausted through the distal opening
is not re-aspirated by the fan. In this regard, the duct has a
minimum length of at least 3 times the diameter of a fan
impeller.
[0013] According to a preferred embodiment, the thermoelectric
device adheres to the thermally active area or the casing defines a
window facing a face of the thermoelectric device opposed to the
exchanger. In both cases, the air flow is adducted through the
exchanger and is inside the casing while the opposite side of the
thermoelectric device exchanges heat outside the casing. This
increases the thermal gradient achieved by the unit for the benefit
of a greater control of the heat exchange with the body.
[0014] According to a preferred embodiment, the casing is
substantially flattened and oblong so as to keep the fan, the heat
exchanger and the air flow side by side and substantially aligned
along its axis, and also allows to convey in an orthogonal
direction to its axis the incoming and outgoing air flows.
[0015] The flattened and oblong shape is compact and allows the
unit to be mountable, for example in clothing filling.
[0016] According to a preferred embodiment, the casing is soft and
elastically hand deformable, for example manufactured by including
a polymeric material based on silicone or thermoplastic
polyurethane. Preferably the polymeric material comprises a polyol
and an isocyanate to obtain the best compromise between flexibility
and flame resistance. In particular, flexibility can be further
regulated through a `chain extender`, i.e. an add-on to polyol and
isocyanate.
[0017] Furthermore, the casing defines precise shapes, e.g. the
duct, the housing for the fan and the thermoelectric device, at
least in an undeformed condition and allows to absorb shocks or
take the position of the body maintaining high user comfort.
[0018] According to a preferred embodiment, the channel comprises
one or more spacers arranged in a transverse position of the
channel to avoid or limit collapses of the channel in case of
applied loads having a component parallel to a height of the cross
section of the channel.
[0019] According to a preferred embodiment, the casing defines an
intake opening for feeding the fan, the intake opening and the
distal opening being both arranged on a face of the housing
opposite to that of the thermally active area.
[0020] Being designed for interaction with a user on the part of
the thermally active area, the most favorable area for the exchange
of air flows is the one opposite to the face facing the body.
[0021] According to a preferred embodiment of the present
invention, a garment comprises the thermoelectric unit as described
in the previous paragraphs, in which the casing is arranged in a
multilayer fabric (so-called "compound") or in a filling delimited
towards the outside from a textile layer. Preferably, the garment
is a fire retardant suit, for example a suit for a race car driver,
and the thermoelectric device is configured to absorb heat through
the thermally active surface.
BRIEF DESCRIPTION OF THE FIGURES
[0022] The present invention will be described below by means of
some preferred embodiments, given as a non-limiting example, with
reference to the attached drawings. These drawings illustrate
different aspects and examples of the present invention and, where
appropriate, structures, components, materials and/or similar
elements in different figures are indicated by similar reference
numbers.
[0023] In particular:
[0024] FIG. 1 refers to a schematic longitudinal section of a
thermoelectric unit according to the present invention; is
[0025] FIG. 2 refers to an exploded perspective view of an
embodiment of the unit schematically shown in FIG. 1;
[0026] FIG. 3 is a perspective view from below of the
thermoelectric unit of FIG. 2;
[0027] FIG. 4 is a graph illustrating experimental results of the
temperature trend of the thermally active area during a cycle of
increase and decrease of the electrical power supply; and
[0028] FIG. 5 is a graph showing experimental results of
stabilization over time of the temperature at constant voltage
supply of the thermoelectric device.
DETAILED DESCRIPTION OF THE INVENTION
[0029] In FIG. 1,1 indicates as a whole a thermoelectric unit
comprising a flexible layer 2 for example comprising a fabric
adapted in use to face a user and, preferably, in contact with the
user's skin, an casing 3 elastically deformable to increase comfort
while the user is moving and carrying the thermoelectric unit 1, a
thermoelectric device 4 inside casing 3 to absorb or give heat to
the user, a fan 5 inside casing 3 to generate an air flow in heat
exchange with thermoelectric device 4 and inside casing 3, and a
channel 6 located downstream of thermoelectric device 4 to adduct
the air flow in a zone distal to that of intake fan 5.
[0030] Furthermore, unit 1 comprises a heat sink 7 inside casing 3
and arranged between fan 5 and channel 6 to receive the air flow
and increase the efficiency of the thermoelectric device 4. Heat
sink 7 operates when the thermoelectric device cools the body; more
generally, an air-solid heat exchanger, for example with fins, is
associated with the thermoelectric device.
[0031] In particular, thermoelectric device 4 is a solid state heat
pump, e.g. a Peltier cell, and is powered by direct current and, in
a first polarity, a face 8 of thermoelectric device 4 facing the
user absorbs heat and produces a cooling sensation; and in an
opposite polarity, face 8 provides heat and produces a feeling of
warming for the user. Consequently, a face of thermoelectric device
4 opposed to face 8 and arranged in heat exchange with heat sink 7
raises its temperature with respect to face 8 when the power supply
is according to the first polarity; and such a face with heat
exchanger 7 has a lower temperature than that of face 8 when the
polarity is reversed.
[0032] Fan 5 is preferably a radial fan and generates an air flow
having a predefined rectilinear direction that reaches channel 6
through heat sink 7 so as to increase the efficiency of
thermoelectric device 4. Channel 6 extends in a substantially
parallel direction to that of the air flow and opens into a
discharge opening 9 distal from fan 5, preferably arranged at one
end of casing 3.
[0033] Casing 3 is connected to flexible layer 2 according to
different methods applied in the clothing manufacturing industry,
for example, both disconnectable through e.g. velcro, snap buttons,
laces or the like, and permanently, for example through adhesives,
welds between polymeric materials or the like. In the diagram of
FIG. 1, face 8 is facing the user's body the flexible layer 2 also
has a face facing the body. A preferred application of the unit of
the present invention is the insertion of casing 3 into the filling
of a garment and, as illustrated in FIG. 1, this requires unit 1 to
be coupled to a fabric or other external flexible layer 10, i.e.
opposed to flexible layer 2, and that a face of flexible layer 2
opposed to that towards the body is in contact with the
filling.
[0034] According to a preferred embodiment of the present
invention, in particular when external flexible layer 10 is
breathable or is a fabric, the cooling or heating action via face 8
requires an air flow through fan 5 such as to pass through flexible
layer external 10 without particular difficulties or impact on the
efficiency of thermoelectric device 4.
[0035] Flexible layer 2 towards the body can also have a weft and
warp spaced apart so as to allow the transmission of heat through
face 8 or require a modification in the area superimposed on face 8
to increase the efficiency of heat transmission. For example, the
modification involves the application of openings and may include
the opening of a window having for example the size of face 8 and,
optionally, the application to the window of a fabric with a
sufficiently spaced weft and warp or the like.
[0036] Face 8 can be completely exposed to flexible layer 2 through
e.g. a window open in casing 3 or casing 3 comprises an area in
contact with face 8 having openings arranged in a matrix or in
another way and shaped in such a way as to allow the heat exchange
between face 8 and the user's body.
[0037] According to a preferred embodiment of the present
invention, both distal opening 9 and an intake opening 11 of fan 5
are either peripheral or opposite to face 8 and to flexible layer 2
so as to face towards a more free area and not occupied by the
user's body and, therefore, more efficiently generate the air
flow.
[0038] According to the embodiment of FIG. 2, fan 5, a central zone
of thermoelectric device 4 and a central zone of an intake port of
the channel 6 are substantially aligned. Furthermore, channel 6 has
a substantially rectilinear shape to distance itself from intake
opening 11 so as to give casing 3 an oblong and substantially
flattened shape. Both distal opening 9 and intake opening 11 are
arranged on the same face of casing 3 opposed to the face 8 (FIG.
3).
[0039] Preferably casing 3, for example comprising two half-shells,
is manufactured of an elastically hand deformable polymeric
material, for example based on silicone or thermoplastic
polyurethane. The latter also has a flame-resistant behavior and is
suitable for applications within heat-resistant clothing such as a
suit for a race car driver. When casing 3 is thus manufactured, it
is important to always keep channel 6 clear even when, for example,
the user presses against the casing with his whole body against a
rigid wall. To counteract this load, one or more spacing
projections 12 are arranged in channel 6, elongated in a transverse
direction, preferably approximately perpendicular, to face 8.
[0040] FIG. 4 illustrates the superimposition of first experimental
data (circumferences--dark color) measuring the electrical power
supply of the thermoelectric device 4 in the cooling mode as the
supply voltage changes in a dynamic increase and decrease cycle;
and second experimental data (squares--light color) measuring the
difference between the ambient temperature, i.e. 24.degree. C., and
the temperature of face 8 as the supply voltage varies according to
the same cycle adopted for the power measurement. The graph shows
the presence of a zone of maximum cooling efficiency around 5 V of
power.
[0041] FIG. 5 illustrates experimental results of the temperature
of face 8 in the cooling mode of the thermoelectric device 4 at a
constant supply voltage over time.
[0042] Finally, it is clear that modifications or variations can be
made to the portable thermoelectric unit according to the present
invention without thereby departing from the scope of protection as
defined by the attached claims.
[0043] For example, the unit is also applicable within sleeping
bags, backs of backpacks, hammocks etc. with or without filling and
with the flexible layer facing the body.
[0044] It is also possible that the user is an individual or an
animal, for example a companion animal.
[0045] Based on these numerous applications, it is possible that
the flexible layer 2 is not of fabric or non-woven fabric, but a
continuous membrane, for example made by molding or laminating, of
a polymeric material.
[0046] According to the embodiment illustrated in FIGS. 2 and 3,
the power supply of the thermoelectric device 4 is external to unit
1 and electrical wires of suitable length electrically connect
device 4 to a battery. However, it is possible to provide a
rechargeable battery or a supercapacitor on board casing 3.
[0047] Further applications in heat-resistant clothing include the
use on board of firefighter suits and for personnel working in
furnaces for metalworking or for foundry work.
* * * * *