U.S. patent application number 10/434307 was filed with the patent office on 2004-03-18 for device for the local cooling or heating of an object.
This patent application is currently assigned to Laing Thermotech, Inc.. Invention is credited to Laing, Birger, Laing, Karsten, Laing, Oliver.
Application Number | 20040052663 10/434307 |
Document ID | / |
Family ID | 31724819 |
Filed Date | 2004-03-18 |
United States Patent
Application |
20040052663 |
Kind Code |
A1 |
Laing, Oliver ; et
al. |
March 18, 2004 |
Device for the local cooling or heating of an object
Abstract
A device for the local cooling or heating of an object by means
of a fluid is disclosed. The device comprises a circulation pump
for the fluid. A thermal contact element for making thermal contact
with the object is integrated in the circulation pump.
Inventors: |
Laing, Oliver; (Stuttgart,
DE) ; Laing, Karsten; (Althutte, DE) ; Laing,
Birger; (Marbach, DE) |
Correspondence
Address: |
FOLEY & LARDNER
P.O. BOX 80278
SAN DIEGO
CA
92138-0278
US
|
Assignee: |
Laing Thermotech, Inc.
|
Family ID: |
31724819 |
Appl. No.: |
10/434307 |
Filed: |
May 7, 2003 |
Current U.S.
Class: |
417/423.8 ;
257/E23.098 |
Current CPC
Class: |
G06F 1/20 20130101; H01L
23/473 20130101; H01L 2924/0002 20130101; F28D 2021/0029 20130101;
H01L 2924/0002 20130101; F04D 29/588 20130101; G06F 1/206 20130101;
H01L 2924/00 20130101 |
Class at
Publication: |
417/423.8 |
International
Class: |
F04B 039/06 |
Foreign Application Data
Date |
Code |
Application Number |
Sep 13, 2002 |
DE |
102 43 026.8 |
Claims
1. A device for the local cooling or heating of an object by means
of a fluid, comprising: a circulation pump for the fluid; and a
thermal contact element for making thermal contact with the object,
said thermal contact element being integrated in said circulation
pump.
2. The device according to claim 1, wherein the thermal contact
element is part of a housing of the circulation pump.
3. The device according to claim 1, wherein the thermal contact
element provides a housing cover of the circulation pump.
4. The device according to claim 1, wherein the thermal contact
element defines a boundary of a swirl chamber of the circulation
pump.
5. The device according to claim 4, wherein an impeller is
rotatably arranged in the swirl chamber.
6. The device according to claim 5, wherein the circulation pump
has a cover plate for the paddle wheel.
7. The device according to claim 5, wherein a through-flow which is
generated by means of the impeller is guided past the thermal
contact element.
8. The device according to claim 5, wherein the impeller is
arranged
9. The device according to claim 1, wherein the thermal contact
element is made from a metallic material.
10. The device according to claim 1, wherein the thermal contact
element is configured substantially as a plate.
11. The device according to claim 1, wherein the circulation pump
is a centrifugal pump.
12. The device according to claim 11, wherein a substantially
spherical bearing is provided for a rotor of the circulation
pump.
13. The device according to claim 11, wherein the circulation pump
comprises an electric motor having a stator and a rotor, between
which a substantially spherical air gap is formed.
14. The device according to claim 11, wherein there is coaxial flow
through the circulation pump.
15. The device according to claim 1, wherein a feed line for liquid
medium is connected to a housing of the circulation pump
transversely with respect to an axis of rotation of a rotor of the
circulation pump.
16. The device according to claim 1, wherein a discharge line for
liquid medium is connected to a housing of the circulation pump
transversely with respect to an axis of rotation of a rotor of the
circulation pump.
17. The device according to claim 1, wherein a discharge line for
discharging liquid medium from the circulation pump and a feed line
for feeding liquid medium to the circulation pump are connected to
the same side of a housing of the circulation pump.
18. The device according to claim 1, wherein the thermal contact
element is arranged on the pressure side of the circulation
pump.
19. The device according to claim 1, wherein the thermal contact
element has fins on its inner side.
20. The device according to claim 19, wherein the fins are adapted
to promote turbulence.
21. The device according to claim 1, wherein blades are arranged on
a rotor in an air gap between a stator and the rotor.
22. The device according to claim 1, wherein a swirl chamber of the
circulation pump has a variable volume.
23. The device according to claim 1, wherein the circulation pump
has a housing part which is flexible and/or is movable in such a
manner that a positive pressure can be exerted on the system.
24. The device according to claim 1, wherein the circulation pump
has a housing part which is flexible and/or is movable to provide
an expansion volume for the liquid.
25. The device according to claim 23, wherein the flexible and/or
movable housing part is arranged on an opposite side of the housing
from the thermal contact element.
26. The device according to claim 1, wherein the thermal contact
element is flexible and/or is mounted movably on a housing of the
circulation pump.
27. The device according to claim 23, wherein a pressure bias is
exertable on the system by a fixing device for fixing the
circulation pump to the object.
28. The device according to claim 1, wherein the circulation pump
is held with respect to the object by means of one or more holding
clips.
29. The device according to claim 1, wherein said thermal contact
includes physical contact with the object.
30. A system for the local cooling or heating of an object,
comprising: a first thermal transfer portion adapted to form a
thermal contact with the object; a second thermal transfer portion
for re-conditioning a thermal transfer fluid; and a circulation
pump for circulating the thermal transfer fluid, through a loop
including the first and second thermal transfer portions, said
circulation pump being integrally formed with at least one of the
first and second thermal transfer portions.
31. A method of locally cooling or heating an object, comprising:
drawing a thermal transfer fluid into a circulation pump; allowing
thermal transfer between the object and the thermal transfer fluid
through a thermal contact element, said thermal contact element
being in thermal contact with the object and being integrally
formed with the circulation pump; and expelling said thermal
transfer fluid out of said circulation pump.
Description
RELATED APPLICATION
[0001] The present disclosure relates to the subject matter
disclosed in German application No. 102 43 026.8 of Sep. 13, 2002,
which is incorporated herein by reference in its entirety and for
all purposes.
FIELD OF THE INVENTION
[0002] The invention relates to a device for the local cooling or
heating of an object by means of a liquid, comprising a circulation
pump for the liquid.
[0003] Devices of this type are used, for example, for the liquid
cooling of microprocessors.
SUMMARY OF THE INVENTION
[0004] In accordance with the invention, a device for the local
cooling or heating of an object is provided which is of simple
design since a thermal contact element for making thermal contact
with the object is integrated in the circulation pump.
[0005] Therefore, according to an embodiment of the invention, a
thermal contact element such as a heat sink or heater which is
brought into contact with the object is part of the circulation
pump. In this way, it is possible to achieve a compact design of a
liquid cooling device or heating device with effective cooling or
heating of the object with which contact is made.
[0006] Furthermore, it is possible to achieve a high level of
efficiency with regard to the cooling or heating, since a fluid is
accelerated before it is brought in contact with the thermal
contact element, and the flow which is generated makes it possible
to achieve good thermal contact with the thermal contact element.
It is then possible for heat to be optimally dissipated or
optimally supplied. It is also possible to use the circulation pump
to establish a flow pattern which is optimal for the removal
(dissipation) of heat or supply of heat.
[0007] By suitably shaping the thermal contact element, in
particular such that it is matched to a contact surface of the
object, it is possible to achieve a good cooling function or
heating function in combination with minimized dimensions.
[0008] In particular, it is advantageous if the thermal contact
element is part of a housing of the circulation pump. As a result,
the device can be produced in a simple way. Furthermore, with
suitable positioning of the circulation pump it is possible to
achieve a cooling function or heating function with regard to the
object: the circulation pump is positioned with the thermal contact
element on the object and is fixed with respect thereto, for
example by means of clips or positively locking connections.
[0009] In particular, it is provided that the thermal contact
element constitutes a housing cover of the circulation pump, so
that the thermal contact element does not form an additional
component and the circulation pump and therefore also the device
can be produced in a simple way.
[0010] In particular, in this case the thermal contact element is a
boundary of a swirl chamber of the circulation pump and confines
the swirl chamber at least at one end thereof. In the swirl
chamber, a swirl is produced in the liquid, and at an outlet this
swirl is converted in a spiral pump housing into pressure for
circulation of the liquid. If the thermal contact element confines
the swirl chamber, it is possible to achieve optimum thermal
coupling between liquid and thermal contact element and therefore
in turn to achieve an optimum dissipation of heat from or supply of
heat to the object.
[0011] In particular, an impeller (paddle wheel), which is driven,
for example, as part of an electric motor and by means of which a
swirl can be generated in the liquid, is rotatably arranged in the
swirl chamber.
[0012] It is also possible for the circulation pump to have a cover
plate, in particular in the form of a covering disk for the paddle
wheel. A cover plate usually increases the pump output, while
without a cover plate the flow velocity is higher. The use or
omission of a cover plate makes it possible to establish the
optimum conditions for the specific application.
[0013] It is very particularly advantageous if a through-flow which
is generated by means of the impeller is guided past the thermal
contact element. By guiding by this flow, it is possible to achieve
optimum thermal coupling between circulation pump and the object,
so that once again optimum cooling or heating can be achieved.
[0014] If the impeller is arranged facing the thermal contact
element, it is possible to establish optimized flow guidance in
order to dissipate heat from the thermal contact element or to
supply heat to the thermal contact element.
[0015] In a variant of an exemplary embodiment, the thermal contact
element is made from a metallic material, such as copper, in order
to achieve a high thermal conductivity, in order, in turn, to allow
optimum dissipation of heat from an object or optimum supply of
heat to an object.
[0016] If the thermal contact element is formed as a plate, which
in particular has a constant height, it is possible to avoid heat
peaks (hot spots) in the thermal contact element.
[0017] In principle, it is possible for the circulation pump to
comprise an electric motor, such as a cylinder motor, a disk motor
or an external rotor motor, or for it to be driven by means of a
permanent-magnetic coupling.
[0018] However, it is very particularly advantageous if the
circulation pump is a centrifugal pump with a spherical electric
motor. It is then possible to achieve a play-free bearing of a
rotor, so that firstly a long service life and therefore a high
reliability of the circulation pump are ensured. Secondly, with a
substantially spherical bearing, the noise produced is minimized,
so that there is reduced operating noise. Furthermore, the overall
height (parallel to the axis of rotation of the rotor) can be
minimized in a centrifugal pump.
[0019] In particular, a substantially spherical bearing for a rotor
of the circulation pump is provided, in order to obtain a play-free
bearing while minimizing the overall height.
[0020] Furthermore, it is expedient if the circulation pump
comprises an electric motor having a stator and a rotor, between
which a substantially spherical air gap is formed. A centrifugal
pump having an electric motor of this type is disclosed by U.S.
Pat. No. 4,728,268 and DE 35 38 504 C2, to which reference is
hereby expressly made.
[0021] Furthermore, it is expedient if there is coaxial flow
through the circulation pump at least in the region between an
inflow region and an outflow region, in order in this way to obtain
optimum distribution of the cooling or heating liquid to the
thermal contact element.
[0022] To minimize the dimensions of the device according to the
invention, a feed line for liquid medium is advantageously
connected to a housing of the circulation pump transversely with
respect to an axis of rotation of a rotor of the circulation pump,
and/or a discharge line for liquid medium is advantageously
connected to a housing of the circulation pump transversely with
respect to an axis of rotation of a rotor of the circulation pump.
In this context, in particular the feed line and/or discharge line
is/are connected to the housing at right angles with respect to the
axis of rotation. As a result, liquid medium can be supplied or
discharged laterally, so that the overall height of the device is
not increased.
[0023] If a discharge line for discharging liquid medium from the
circulation pump and a feed line for feeding liquid medium to the
circulation pump are connected to the same side of a housing of the
circulation pump, it is also possible to minimize the lateral
dimensions of the device and in particular the space required to
form a loop for the liquid medium.
[0024] The thermal contact element is advantageously arranged on
the pressure side of the circulation pump (and not on the suction
side), in order in this way to obtain optimum flow guidance and in
particular to be able to apply a flow with a high degree of
turbulence to the thermal contact element, in order in turn to
achieve optimum thermal coupling.
[0025] To increase the thermal contact surface area of the liquid
in the thermal contact element, it is possible for the thermal
contact element to have fins on its inner side. These may, for
example, be circular or spiral walls.
[0026] In a variant of an embodiment, the fins are formed in such a
way as to promote turbulence, in order in this way to further
improve the thermal coupling.
[0027] In a variant of an embodiment, it is provided that in an air
gap between a stator and a rotor, blades are arranged on the rotor,
in order in particular to generate additional swirl in the liquid.
The blades are disposed in such a way that the spherical geometry
is substantially retained.
[0028] It is advantageous for a swirl chamber of the circulation
pump to have a variable volume and in particular for a confining
element of the swirl chamber to be able to move relative to the
remainder of the housing. In this way, it is possible to provide an
expansion volume for the liquid without having to provide separate
expansion means. (The liquid expands when heated.) Furthermore, in
this way it is possible to exert an initial pressure in order in
particular to prevent air from entering into the system.
[0029] In particular, it is provided that the circulation pump has
a housing part which is formed flexibly and/or is movable, and in
particular is disposed movably on the housing, in such a manner
that it is possible to exert a positive pressure on the system. In
this way, it is possible to prevent air from entering into the
system. By way of example, the housing part may be a flexible
plate, a flexible diaphragm or a bellows.
[0030] Furthermore, it is expedient if the circulation pump has a
housing part which is formed flexibly and/or is movable in such a
manner that it is possible to provide an expansion volume for the
liquid, so that there is no need to provide any separate expansion
vessels in a liquid circuit.
[0031] It is possible for the flexible and/or movable housing part
to be arranged on the opposite side of the housing from the contact
element, and in particular to be arranged on a suction side of the
housing. The corresponding housing part is in this case arranged
substantially parallel to a surface of the object which is to be
cooled or heated and in particular is oriented parallel to the
contact element. However, the flexible and/or movable housing part
may also be formed by the contact element itself.
[0032] The thermal contact element is then of flexible form and/or
is mounted movably on a housing of the circulation pump. Then, by
way of example, the thermal contact element is formed as a flexible
plate which, however, still has sufficient inherent rigidity. In
this way, it is possible to provide an expansion volume for the
liquid after heating and also to exert a positive pressure on the
system.
[0033] It is also possible for the thermal contact element to be a
thin diaphragm which positions itself against the object or is
surrounded by a bellows.
[0034] In particular, it is provided that a positive pressure can
be exerted on the system by means of a fixing device for fixing the
circulation pump to the object. A fixing device of this type can be
used to fix the circulation pump with the contact element on or
with respect to the object which is to be cooled or heated. This
can be achieved by exerting a corresponding holding force. This
holding force can also be used to exert the positive pressure, it
being possible for the force to act directly on the flexible and/or
movable housing part or for this force to be imparted via the
holding force.
[0035] In particular, it is provided that the circulation pump is
held with respect to the object by means of one or more clips. In
this way, it is possible to achieve simple fixing of the
circulation pump and therefore of the device for local cooling or
heating with respect to the object.
[0036] The following description of preferred embodiments, in
combination with the drawing, serves to provide a more detailed
explanation of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0037] FIG. 1 shows a partially cutaway view of an exemplary
embodiment of a device according to the invention for the local
cooling or heating of an object;
[0038] FIG. 2 shows a plan view in the direction A of the device
shown in FIG. 1;
[0039] FIG. 3 shows a schematic illustration of an exemplary
embodiment of a thermal contact element;
[0040] FIG. 4 shows a further exemplary embodiment of a thermal
contact element;
[0041] FIG. 5 shows a further exemplary embodiment of a thermal
contact element;
[0042] FIG. 6 shows a schematic view of a fixing device for fixing
a circulation pump to the object; and
[0043] FIG. 7 shows a variant of the exemplary embodiment
illustrated in FIG. 6.
DETAILED DESCRIPTION OF THE INVENTION
[0044] An exemplary embodiment of a device according to the
invention for the local cooling or heating of an object, which is
denoted overall by 10 in FIG. 1, comprises a circulation pump 12,
by means of which a fluid, such as water or other liquids, can be
guided in a loop (FIG. 2) as a heat transfer medium. The heat
transfer medium can be used as a cooling medium, in order to cool
an object 14, such as for example an electronic component, such as
a processor, which is positioned on a circuit board 16, for
example. The heat transfer medium can also be used for heating an
object.
[0045] The circulation pump 12 comprises a housing 18. A feed line
20 is provided to allow a fluid to enter into the housing 18 by
means of an opening 22 leading into a suction side of the
circulation pump 12. A discharge line 26 leads away from the
housing 18 via an opening 24 from a pressure side (delivery side)
of the circulation pump 12.
[0046] The housing 18 may be pressed onto the object 14, for
example by means of pressure-exerting clips (not shown).
[0047] If the device is used as a cooling device, a cooling fluid,
such as water, is supplied via the feed line 20, and heated cooling
liquid which has been heated as a result of the cooling of the
object 14, is discharged via the discharge line 26.
[0048] If the device is used as a heating device, a heating fluid
is supplied via the feed line 20 and then heats the object 14 and,
in the process the heating fluid is cooled. The cooled heating
liquid is discharged via the discharge line 26.
[0049] The discharge line 26 and the feed line 20 are connected to
one another outside the housing 18 of the circulation pump 12, in
order to form a loop 28 for the liquid. This loop 28 has a cooling
section or heating section 30 which is arranged outside the housing
18 and along which heated cooling liquid can be cooled, for example
by means of air cooling, or cooled heating medium can be heated.
The cooling section or heating section 30 for this purpose has a
suitable surface area to allow effective cooling or heating.
[0050] The thermal contact between the fluid and the object 14 is
provided by a thermal contact element 32 which is integrated into
the circulation pump 12. The thermal contact element 32 preferably
provides and, in particular, forms a housing cover for the housing
18. The thermal contact element 32 may be, for example, in the
shape of a plate and made from a metallic material.
[0051] To form the thermal contact, the thermal contact element 32
touches the object 14 over the largest possible surface area. It is
preferable for that surface of the thermal contact element 32 which
faces the object 14 to be at least as large as a contact surface of
the object 14.
[0052] An interior space 36, in which an electric motor, denoted
overall by 38, is accommodated, is formed in the housing 18 of the
circulation pump 12. The electric motor comprises a rotor 42 which
can rotate about an axis of rotation 40.
[0053] The opening 22 for the feed line 20 and the feed line 20
itself, at least in the region of the opening, and also the opening
24 and the discharge line 26, at least in the region of this
opening 24, are oriented transversely, and in particular at right
angles, with respect to the axis of rotation 40, in order to be
able to maintain a low height of the circulation pump 12 and,
therefore, of the device 10 in the direction of the axis of
rotation 40.
[0054] The opening 22 and the opening 24 are preferably arranged on
the same (transverse) side 43 of the housing 18 of the circulation
pump 12.
[0055] A swirl chamber 44, in which a swirl is imparted to liquid
which has been supplied via the feed line 20, using an impeller 46
(paddle wheel) which is connected in a rotationally fixed manner to
the rotor 42, and in which swirling liquid flows, is formed in the
interior space 36 of the housing 18. Pressure conversion takes
place in a spiral housing of the circulation pump 12, in order for
the liquid to be pumped through the circuit 28. The liquid is also
guided past the thermal contact element 32 in order to transfer
heat.
[0056] The swirl chamber 44 is formed in the interior space 36
between walls 48, the thermal contact element 32 also being
positioned on these walls, facing the object 14. One or more fluid
seals 52, for example in the form of O-rings, is/are disposed
between end faces 50 of these walls 48 and the thermal contact
element 32.
[0057] The electric motor 38 of the circulation pump 12 may, for
example, be formed as a cylinder motor, as a disk motor or as an
external rotor motor, or alternatively the circulation pump may be
driven by means of a permanent-magnetic coupling.
[0058] In the exemplary embodiment shown in FIG. 1, the circulation
pump 12 is formed as a centrifugal pump with a corresponding
electric motor 38 which comprises a stator 54, which is connected
in a rotationally fixed manner to the housing 18, and a rotatably
mounted rotor 42.
[0059] The rotor 42 is mounted on a convex sliding partner 60 by
means of a bearing cap 58.
[0060] The convex sliding partner 60, which is substantially formed
in particular as a sphere, is seated on a bearing support 62 which
extends in the direction of the axis of rotation 40 and in
particular is formed concentrically with respect thereto.
[0061] The bearing cap 58 is connected in a rotationally fixed
manner to the paddle wheel 46.
[0062] The bearing cap 58 on the sliding partner 60 forms a
substantially spherical bearing. As a result, the dimensions of the
circulation pump 12 for the bearing of the rotor 42 can be
minimized in the direction of the axis of rotation 40.
[0063] The rotor 42 of the electric motor 38 has a substantially
spherical contour facing the walls 48 of the housing 18 (i.e., a
contour which matches a partial region of a spherical surface). A
wall 64, which is, for example, made from stainless steel,
surrounds the rotor 42. The rotor 42 forms a single unit with the
paddle wheel 46.
[0064] A through-flow region 66, which in particular is arranged
concentrically with respect to the axis of rotation 40 and is, for
example, approximately annular in cross section (with ribs disposed
in the annular space), is formed around the bearing support 62 at
the rotor 42. This through-flow region 66 connects an inflow region
68 of the circulation pump 12, which in turn is connected to the
feed line 20, to the swirl chamber 44. The paddle wheel 46 is
disposed in the swirl chamber 44, so that the pressure side of the
circulation pump 12 is formed here, while the inflow region 68
represents the suction side. Then, liquid is guided through the
circulation pump 12 via the through-flow space 66, and a swirl is
imparted to the liquid which is conducted through by the paddle
wheel 46; the pressure required to pump the liquid through the loop
28 is then produced.
[0065] The bearing support 62 is held on the housing 18 by means of
radial ribs 67, it being ensured that the liquid can flow past. The
bearing cap 58 is held in a rotationally fixed manner on the rotor
42 by means of radial ribs 69, it once again being ensured that the
liquid can flow past in order to form the through-flow region
66.
[0066] In a variant of an embodiment, a circuit board 70 is
positioned in the housing 18. Coils for the motor and electrical
connectors for the coils may be mounted on the circuit board
70.
[0067] The stator 54 is formed by means of coil windings (not shown
in the drawing) and magnetic return path elements 71 (yoke
elements).
[0068] Between the rotor 42 and the stator 54 there is a
substantially spherical wall 72 which is made, for example, from a
plastics material. Between the rotor 42 and the spherical stator 54
an air gap 74 is defined, which is substantially spherical, i.e. is
bounded with respect to the wall 72 by a part of a substantially
spherical surface and is likewise bounded with respect to the rotor
42 by part of a substantially spherical surface, the two spherical
surfaces lying essentially concentrically with respect to one
another. The centers of the spheres lie on the axis of rotation 40
in the center of the sliding partner 60, via which, once again by
means of the bearing cap 58, the rotor 42 is mounted rotatably in
the housing 18 of the circulation pump 12. The spherical surfaces
may be slightly non-concentric with regard to the direction along
the axis of rotation 40.
[0069] The paddle wheel 46 is positioned in the swirl chamber 44,
facing the thermal contact element 32. It is possible for the
paddle wheel 46 to be provided with a cover plate 76 facing the
thermal contact element 32.
[0070] The device 10 according to the invention for cooling or
heating the object 14 functions in the following way:
[0071] The housing 18 of the circulation pump 12 is positioned with
respect to the object 14 in such a way that the thermal contact
element 32 is seated on the contact surface 34 of the object
14.
[0072] By way of example, the object 14 is a microprocessor which
is to be cooled using water.
[0073] Then, cooling water is guided in the loop 28, by the
circulation pump 12, past an inner side 78 of the thermal contact
element 32, which is opposite to the contact surface 34 of the
object 14.
[0074] In this arrangement, it is possible for this inner side to
have fins in order to increase the surface area, these fins being
provided in particular with a structure which increases the
turbulence. By way of example, circular or spiral walls project
toward the paddle wheel 46. In this way, the flow and in particular
the flow of the cooling water past the thermal contact element 32
can be improved and the thermal contact can be improved, so that
heat can be optimally dissipated and as a result the object 14 can
be optimally cooled.
[0075] Cool cooling water is guided into the inflow region 68 via
the feed line 20. It then flows through the through-flow region 66
coaxially with respect to the axis of rotation 40. A swirl is
imparted to this cooling water by the paddle wheel 46; this is then
followed by pressure conversion in the spiral housing, in order to
pump the cooling water through the loop 28.
[0076] At the paddle wheel 46, the cooling water flows spirally
outward with respect to the axis of rotation 40 and past the inner
side 78 of the thermal contact element 32. As a result, heat can be
dissipated from the thermal contact element 32 and therefore in
turn from the object 14 through the cooling water, which
correspondingly has taken up this heat.
[0077] The cooling section 30 has, by way of example, a
heat-transfer surface area which is three times to thirty times
larger than the surface area of the inner side 78 of the thermal
contact element 32 via which heat can be dissipated to the cooling
water.
[0078] As an alternative or in addition to the paddle wheel 46, it
is possible for blades to be disposed on the rotor 42 in the air
gap 74, with the spherical symmetry of the arrangement being
substantially retained.
[0079] According to the invention, a centrifugal pump is provided
as circulation pump 12, with substantially spherical bearing of the
rotor 42. This spherical bearing via the bearing cap 58 and the
sliding partner 60 results in a high freedom of play and therefore
a long service life of the circulation pump 12 combined, at the
same time, with a low level of noise being produced during
operation.
[0080] Furthermore, it is possible to produce low overall heights
in the direction of the axis of rotation 40, so that it is possible
to produce a compact device for example for cooling a
microprocessor 14. The fact that the thermal contact element 32 is
integrated in the circulation pump 12, and in particular the fact
that it is designed as a housing cover, means that it is possible
to achieve a simple and space-saving structure of the device 10. In
particular, there is no need for an external thermal contact
element. The high flow velocities within the housing 18 of the
circulation pump 12 can be utilized directly to dissipate heat from
the object 14. The paddle wheel 46 directly faces the thermal
contact element 32 and therefore the object 14.
[0081] In the exemplary embodiment shown in FIG. 1, the thermal
contact element 32 is formed as a rigid plate which is made from a
material with a good thermal conductivity, such as copper.
[0082] It is also possible for the thermal contact element to be
elastic. In an exemplary embodiment which is shown in FIG. 3, a
flexible plate 80 is provided as thermal contact element 32, this
flexible plate having sufficient inherent rigidity. In particular,
the flexible plate 80 comprises a thermal contact region 82 and a
flexibility region 84, in order to effect optimum contact between
the plate 80 and the object 14.
[0083] The flexibility of the thermal contact element 80 means that
the volume of the swirl chamber 44 is variable. As a result, it is
possible to absorb expansion of the liquid without any load being
imposed on the housing 18. Moreover, in this way it is possible to
exert a pressure bias on the system.
[0084] It is also possible for the thermal contact element to
comprise a membrane which rests against the object 14 or to
comprise a flexible membrane.
[0085] In an exemplary embodiment which is shown in FIG. 4, the
thermal contact element comprises bellows 86 with a contact plate
88 for placing onto the object 14. The fact that the structure is
formed as bellows 86 means that the contact plate 88 is moveable
relative to the paddle wheel 46, with the result that, once again,
the volume of the swirl chamber 44 can be varied.
[0086] It is also possible to provide a thermal contact element 90
in conical form, as shown in FIG. 5, which may be a rigid
arrangement or a flexible arrangement.
[0087] The device 10 according to the invention can also be used
for local heating of the object 14 via the thermal contact element
32 and the contact surface 34 of the object 14 if, in a
corresponding way, in particular hot water is conducted past the
inner side 78 of the thermal contact element 32 as heating
liquid.
[0088] As shown in FIG. 6, the circulation pump 12 is fixed to the
object 14 which is to be cooled or heated by means of a fixing
device 92. By way of example, the fixing device 92 comprises one or
more holding clips 94. If there is a plurality of holding clips 94,
these clips are spaced apart from one another.
[0089] A holding clip 94 is formed in the shape of a bracket and
can be placed onto a side of the housing 18 which is remote from
the thermal contact element 32. Ends 96a, 96b can be used to fix a
holding clip 94 to the object 14, which has corresponding holding
recesses 98a, 98b. However, these holding recesses may also be
arranged on the circuit board 16 or on a base which holds the
circuit board 16.
[0090] The holding clip 94 is formed as a clamping bracket with a
tensioning lever 100. When this tensioning lever 100 is open, the
circulation pump 12 can be placed onto the object 14 or the
circulation pump 12 can be pushed into the space between the
holding clip 94 and the object 14. If the tensioning lever is then
closed, which is the position illustrated in FIG. 6, a force is
exerted in the direction of the object 14 via a bracket region 102,
with the result that, in turn, the housing 18 of the circulation
pump 12 is pressed onto the object 14 and as a result the
circulation pump 12 with the contact element 32 is fixed on the
object 14 or is fixed with respect to this object 14.
[0091] With holding clips 94 of this type, it is possible to
achieve rapid fixing of the circulation pump 12 to the object 14 or
to rapidly exchange the circulation pump 12.
[0092] If the thermal contact element 32 is not formed as a rigid
plate, but rather as a flexible contact element or as a contact
element which can move with respect to the housing 18, as shown in
FIGS. 3 to 5 and outlined in this context, it is possible for a
positive pressure to be exerted on the system via the fixing device
92 and the holding clips 94, in order to prevent the penetration of
air. In this case, the thermal contact element forms a housing part
which is flexible or is mounted movably on the housing 18 and with
the aid of which it is possible to exert the positive pressure on
the system.
[0093] It is also possible, as shown in FIG. 7, for a housing part
104 which is not formed by the contact element to be formed
flexibly and/or arranged movably on the housing 18. This
corresponding housing part 104 may, for example, be formed as
bellows, as a flexible plate or as a flexible membrane, as
described above. In this case, in particular this housing part 104
is arranged on the opposite side from the thermal contact element
32, parallel to the thermal contact element 32, and in particular
parallel to a surface of the object 14. In the exemplary embodiment
shown in FIG. 7, this flexible and/or movable housing part is
disposed on the suction side of the circulation pump 12.
[0094] In the variant shown in FIG. 7, the circulation pump 12 is
once again held on the object 14 by means of holding clips 94. The
bracket region 102 in this case acts directly on the flexible
and/or movable housing part 104 and therefore exerts a positive
pressure on the system in order to prevent air from entering into
the system. The fixing device 92 and the holding clips 94 therefore
serve both to fix the circulation pump 12 to the object 14 and to
exert said positive pressure on the system.
[0095] In the exemplary embodiment shown in FIG. 6, the positive
pressure is exerted indirectly via the holding clips 94 as a result
of the housing 18 of the circulation pump 12 being pressed onto the
object 14 if the thermal contact element is flexibly and/or
movably.
[0096] In the embodiment shown in FIG. 7, the fixing device 92
exerts a force directly on the flexible and/or movable housing part
104.
[0097] While particular embodiments of the present invention have
been disclosed, it is to be understood that various different
modifications and combinations are possible and are contemplated
within the true spirit and scope of the appended claims. There is
no intention, therefore, of limitations to the exact abstract and
disclosure herein presented.
* * * * *