U.S. patent application number 10/809823 was filed with the patent office on 2005-04-07 for installation for the preparation of hot water.
This patent application is currently assigned to Bravilor Holding B.V.. Invention is credited to Roet, Frank Petrus Nicolaas, van Steenderen de Kok, Johannes Jacobus, Verhoeven, Romanus Eduard.
Application Number | 20050072853 10/809823 |
Document ID | / |
Family ID | 32822959 |
Filed Date | 2005-04-07 |
United States Patent
Application |
20050072853 |
Kind Code |
A1 |
Roet, Frank Petrus Nicolaas ;
et al. |
April 7, 2005 |
Installation for the preparation of hot water
Abstract
Disclosed is an installation for the preparation of hot water.
The installation includes a cold water reservoir, a heating unit, a
cold water pipe between the cold water reservoir and the heating
unit, a draw-off point for drawing off hot water, a hot water pipe
between the heating unit and the draw-off point and a pump for
making water flow from the cold water reservoir through the cold
water pipe, the heating unit and the hot water pipe to the draw-off
point. A vent pipe is connected to at least one of the said
pipes.
Inventors: |
Roet, Frank Petrus Nicolaas;
(Alkmaar, NL) ; Verhoeven, Romanus Eduard;
(Heerhugowaard, NL) ; van Steenderen de Kok, Johannes
Jacobus; (Heerhugowaard, NL) |
Correspondence
Address: |
William H. Logsdon
WEBB ZIESENHEIM LOGSDON ORKIN & HANSON, P.C.
700 Koppers Building
436 Seventh Avenue
Pittsburgh
PA
15219-1818
US
|
Assignee: |
Bravilor Holding B.V.
Heerhugowaard
NL
|
Family ID: |
32822959 |
Appl. No.: |
10/809823 |
Filed: |
March 25, 2004 |
Current U.S.
Class: |
237/19 |
Current CPC
Class: |
A47J 31/36 20130101;
A47J 31/5253 20180801; A47J 31/5255 20180801; A47J 31/469 20180801;
A47J 27/21 20130101 |
Class at
Publication: |
237/019 |
International
Class: |
F24H 001/22 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 26, 2003 |
NL |
1023023 |
Claims
1-8. (canceled)
9. An installation for the preparation of hot water, comprising: a
cold water reservoir, a heating unit, a cold water pipe between the
cold water reservoir and the heating unit, a draw-off point for
drawing off hot water, a hot water pipe between the heating unit
and the draw-off point, a pump for making water flow from the cold
water reservoir through the cold water pipe, the heating unit and
the hot water pipe to the draw-off point, and a vent pipe connected
to at least one of the cold water pipe and the hot water pipe.
10. The installation according to claim 9, wherein the pump is
installed in the cold water pipe and, viewed in the direction of
flow of the water, the vent pipe is connected to the cold water
pipe downstream of the pump and upstream of the heating unit.
11. The installation according to claim 10, wherein a further vent
pipe is connected to the hot water pipe.
12. The installation according to claim 9, wherein the pump is
installed in the hot water pipe and, viewed in the direction of
flow of the water, the vent pipe is connected to the hot water pipe
downstream of the heating unit and upstream of the pump.
13. The installation according to claim 12, wherein a further vent
pipe is connected to the hot water pipe downstream of the pump.
14. The installation according to claim 9, wherein the vent pipe
runs upwards to the level above a highest water level in the
installation and runs downwards from the level.
15. The installation according to claim 14, wherein a section of
the vent pipe running downwards discharges above the cold water
reservoir.
16. The installation according to claim 9, wherein the cold water
reservoir is connected via a controllable tap to a cold water feed
pipe and a water level in the cold water reservoir is measured by a
level meter that gives a signal to open the tap when the water
level falls below a set level and gives a signal to close the tap
when the set level is exceeded.
17. The installation according to claim 10, wherein the vent pipe
runs upwards to the level above a highest water level in the
installation and runs downwards from the level.
18. The installation according to claim 12, wherein the vent pipe
runs upwards to the level above a highest water level in the
installation and runs downwards from the level.
19. The installation according to claim 17, wherein a section of
the vent pipe running downwards discharges above the cold water
reservoir.
20. The installation according to claim 18, wherein a section of
the vent pipe running downwards discharges above the cold water
reservoir.
21. The installation according to claim 10, wherein the cold water
reservoir is connected via a controllable tap to a cold water feed
pipe and a water level in the cold water reservoir is measured by a
level meter that gives a signal to open the tap when the water
level falls below a set level and gives a signal to close the tap
when the set level is exceeded.
22. The installation according to claim 12, wherein the cold water
reservoir is connected via a controllable tap to a cold water feed
pipe and a water level in the cold water reservoir is measured by a
level meter that gives a signal to open the tap when the water
level falls below a set level and gives a signal to close the tap
when the set level is exceeded.
Description
FIELD OF THE INVENTION
[0001] The invention relates to an installation for the preparation
of hot water, comprising:
[0002] a cold water reservoir,
[0003] a heating unit,
[0004] a cold water pipe between the cold water reservoir and the
heating unit,
[0005] a draw-off point for drawing off hot water,
[0006] a hot water pipe between the heating unit and the draw-off
point,
[0007] a pump for making water flow from the cold water reservoir
through the cold water pipe, the heating unit and the hot water
pipe to the draw-off point.
STATE OF THE ART
[0008] An installation of this type is described in EP 0 771 542.
In this installation the pump is installed in the cold water pipe
between the cold water reservoir and the heating unit, However, the
invention yet to be described is not restricted to this and also
covers installations where the pump has been installed in the hot
water pipe between the heating unit and the draw-off point.
[0009] One problem that arises in such an installation is the
occurrence of vapour bubbles and air bubbles in the various
components of the installation. These bubbles can disturb the flow
of water through the installation and thus, for example, have a
severe adverse effect on the functioning of measurement systems
that function on the basis of an undisturbed uniform flow of water.
In general, the operation of the pump will also be influenced by
vapour bubbles or air bubbles in the water. The pump will
consequently no longer deliver a uniform stream of water, as a
result of which the measurability of the pumping process is
adversely affected.
[0010] The vapour bubbles and air bubbles can get into the water in
various ways.
[0011] The heating unit constitutes a first source of vapour
bubbles. In a number of cases what is concerned here is
flow-through heating, where the cold water is fed through a
reservoir which has a feed connection and a discharge connection,
an (in general electric) heating element being arranged in the
reservoir. The water in the reservoir is kept close to boiling
point by the thermostat-controlled heating element. Certainly in
the vicinity of the element, boiling phenomena will arise and air
bubbles and vapour bubbles will be formed.
[0012] In other cases what is concerned is a heat exchanger with a
reservoir which contains hot water that is kept at a desired
temperature by means of a thermostat-controlled heating element. A,
for example spirally wound, pipe through which the cold water is
fed also runs through this reservoir. If the sizing is chosen
correctly, cold water flowing in at the inlet connection will be
heated in the heat exchanger to a high temperature that can
approach the boiling point. As a result of the incipient boiling
process, air and vapour bubbles will be able to develop, certainly
close to the outlet connection, which bubbles are entrained by the
flowing water or cling to a pipe wall and impede the flow at this
location.
[0013] The pump constitutes a second source of air bubbles. In
general, a certain amount of gas will be dissolved in the water. As
a result of the turbulent movements of the water in the pump some
of these gases can be liberated and form air bubbles, as a result
of which the operation of the pump is impaired. These air bubbles
as well will be entrained by the flowing water. If the flow ceases,
air and vapour bubbles present in the pipes can deposit on the wall
of the pipe and thus disturb a further flow of water.
[0014] The cold water reservoir is another source of air bubbles.
Fresh water from a supply line is introduced into this reservoir in
order to keep the water in the reservoir at a desired level. This
introduction of fresh water frequently gives rise to turbulence, as
a result of which air can be entrapped in the water, which then can
lead to the problems indicated above in other parts of the
installation
[0015] The aim of the invention is, now, to avoid the
abovementioned disadvantages.
BRIEF DESCRIPTIONS OF THE INVENTION
[0016] In order to meet this aim, an installation of the type as
described in the first paragraph is now provided, which
installation according to the invention is characterised in that a
vent pipe is connected to at least one of the said pipes. By
removing vapour bubbles and air bubbles via this (these) vent
pipe(s) the abovementioned disadvantages are avoided and the
abovementioned aim is met.
[0017] In principle, there are two locations where the pump can be
incorporated in the system, i.e. between the cold water reservoir
and the heating unit or between the heating unit and the draw-off
point.
[0018] A first preferred embodiment of the invention is, now,
characterised in that the pump is installed in the cold water pipe
and in that, viewed in the direction of flow of the water, a vent
pipe is connected to the cold water pipe downstream of the pump and
upstream of the heating unit. Bubbles that have formed in the pump
or possibly were already present in the water are removed from the
water through this vent pipe.
[0019] In a further development of this first embodiment, a further
vent pipe is connected to the hot water pipe. The vapour bubbles
and air bubbles that have formed in the heating unit are discharged
via this further vent pipe.
[0020] A second embodiment of the invention is characterised in
that the pump is installed in the hot water pipe and that, viewed
in the direction of flow of the water, a vent pipe is connected to
the hot water pipe downstream of the heating unit and upstream of
the pump.
[0021] In a further development of this second embodiment, a
further vent pipe is connected to the hot water pipe downstream of
the pump. The vapour bubbles and air bubbles that have formed in
the pump are discharged via this further vent pipe.
[0022] In all cases it is furthermore preferable that each vent
pipe runs upwards to a level above the highest water level in the
installation and runs downwards from that point. As a result any
moisture that has formed in the vent pipe as a result of
condensation is not picked up in the stream of water, where it
would interfere with any measurements of the water flow, but is
discharged to the outside via the section running downwards. In
this context it is preferable that the section of a vent pipe
running downwards discharges above the cold water reservoir. In
this case the condensate will serve as feed water for topping up
water in the cold water reservoir and will not reach an
uncontrolled location in the installation.
DESCRIPTION OF THE FIGURES
[0023] The invention will now be discussed in more detail with
reference to the appended drawings, in which:
[0024] FIG. 1 shows an installation from the state of the art,
[0025] FIG. 2 shows a first diagrammatic embodiment of an
installation according to the invention,
[0026] FIG. 3 shows a second diagrammatic embodiment of an
installation according to the invention, and
[0027] FIG. 4 shows a third, more detailed embodiment of an
installation according to the invention
DETAILED DESCRIPTION
[0028] FIG. 1 shows an installation from the state of the art. This
installation is provided with a cold water reservoir 10, a heating
unit 11, a cold water pipe 12 between the cold water reservoir 10
and the heating unit 11, a draw-off point 13 for drawing off hot
water, a hot water pipe 14 between the heating unit 11 and the
draw-off point 13, and a pump 15. The pump 15 provides for the flow
of water from the cold water reservoir 10 through the cold water
pipe 12, the heating unit 11 and the hot water pipe 14 to the
draw-off point 13.
[0029] The heating unit 11 is filled with a liquid (generally
water) that is kept at a predetermined temperature (just below 100
degrees C) by an electric heating element 17. This element is
actuated in a known manner by a controller 21 on the basis of
signals from a thermostat (not shown). This is assumed to be known
to those skilled in the art.
[0030] The level of the water in the reservoir 10 can, for example,
be controlled by a level sensor 18 that gives a signal to a
controller 19 that controls a tap 20 to allow water to flow from a
feed pipe into the reservoir as soon as the water falls below the
level of the sensor. The various aspects are also considered to be
clear to those skilled in the art and not to require any further
explanation.
[0031] Furthermore, a flow meter 22, by means of which the quantity
of water flowing through is measured, is fitted in the cold water
pipe. On the basis of signals from this flow meter, the controller
21 will control the pump in such a way that after switching on the
pump a predetermined quantity of hot water is supplied via the
draw-off point 13, after which the pump is switched off.
[0032] As has already been indicated above, vapour bubbles and air
bubbles that have an adverse effect on the operation of a pump can
be formed at various locations in this installation, which bubbles
have an adverse effect on the functioning of the flow meter 22 and
can impede the uniform flow of the water because these bubbles can
cling to the wall of the pipes.
[0033] The invention now proposes to remove these vapour bubbles
and air bubbles via vent pipes. An installation adapted in
accordance with the invention for this purpose is shown
diagrammatically in FIG. 2.
[0034] The installation in FIG. 2 is provided with the same
components as in FIG. 1 and these are indicated by the same
reference numerals, The components 10-22 thus do not need to be
discussed again. In accordance with the invention a vent pipe 23
has been added that is connected downstream of the pump 15 but in
any event upstream of the flow meter 22. Air bubbles that have
formed in the pump 15 or possibly were already present in the pipe
12 upstream of the pump are discharged via this vent pipe into the
atmosphere. The result is that a calm stream of water without
bubbles is fed to the flow meter, as a result of which this flow
meter is able to function well and is able to give an accurate
signal. The vent pipe is, for example, connected at a high point,
in particular the highest point, of the cold water pipe 12 between
the pump 15 and the flow meter 22 assuming that the majority of the
air and vapour bubbles will collect at this location.
[0035] Furthermore, in accordance with the invention a second vent
pipe 24 is connected to the hot water pipe, for example close to
the outflow connection of the heating unit 11. Air bubbles and
vapour bubbles that have been generated in the heating unit are
discharged via this pipe 24 into the atmosphere. As a result a calm
stream of water without bubbles and without sputtering is supplied
via the draw-off point to the user.
[0036] Vent pipes can also be used successfully in an embodiment
where the pump is downstream of the heating unit in order to remove
vapour bubbles and air bubbles from the installation. FIG. 3 shows
this diagrammatically.
[0037] FIG. 3 shows, diagrammatically, a second embodiment of an
installation according to the invention. This installation is
provided with a cold water reservoir 30, a heating unit 31, a cold
water pipe 32 between the cold water reservoir 30 and the heating
unit 31, a draw-off point 33 for drawing off hot water, a hot water
pipe 34 between the heating unit 31 and the draw-off point 33, and
a pump 35. In this case the pump 35 is accommodated in the hot
water pipe 34.
[0038] In this case the heating unit is of the flow-through type.
The unit is provided with a boiler 36 with an inlet connection to
which the cold water pipe 32 is coupled and an outlet connection to
which the hot water pipe 34 is coupled. In the heating unit there
is a heating element 37 that is thermostatically powered by the
controller 38 and that is in direct contact with the water flowing
over it.
[0039] The tap 41, the level sensor 42 and the controller 43 have
the same function as the corresponding components 18, 19 and 20
described above and therefore require no further discussion.
[0040] In this embodiment vent pipes 39 and 40 are fitted to the
hot water pipe 34 and specifically just downstream of the heating
unit 31 and just downstream of the pump 35, respectively. Under
certain circumstances the pipe 40 can optionally be omitted in
those cases where air bubbles and/or vapour bubbles in the hot
water pipe downstream of the pump are considered to be less
important because they cannot influence the functionring of the
installation any more.
[0041] In FIG. 3 there is no longer a flow meter. It has been found
that by virtue of the measures according to the invention such a
uniform stream of water through the installation is achieved that
it suffices to activate the pump 35 for a predetermined period and
thus to supply a predetermined quantity of hot water via the
draw-off unit 33.
[0042] Finally, FIG. 4 shows an embodiment of the type with the
pump in the cold water pipe and with further more practically
oriented details.
[0043] The installation is provided with a cold water reservoir 50,
a heating unit 51 of the flow-through type, a cold water pipe 52
between the cold water reservoir 50 and the heating unit 51, a
draw-off point 53 for drawing off hot water, a hot water pipe 54
between the heating unit 51 and the draw-off point 53, and a pump
55 driven by a motor 68. In this case the pump 55 is accommodated
in the cold water pipe 52. In the heating unit 51 the water flows
over the heating element 57 and is heated. The temperature is
controlled by a controller 58 on the basis of signals from a
temperature sensor 64.
[0044] The water in the reservoir 50 is kept at the desired level
by means of the tap 61 connected to a water feed pipe 62, which tap
61 is opened and closed by the controller 58 on the basis of
signals from the float 63. The mode of operation of the components
61, 62 and 63 is once again assumed to be known. There is also an
overflow pipe 65 in the reservoir 50, which overflow pipe 65 is
intended only for emergencies.
[0045] The installation is provided with a first vent pipe 59 that
is connected to the cold water pipe 52 at a location downstream of
the pump 55 and preferably close to the highest point of the pipe
52. The pipe 59 runs upwards to a level that is above the highest
level that the water can reach in the installation. From this level
the pipe bends over and further extends downwards over a certain
distance. This downward extension is indicated by 66 in the figure.
What is achieved by this means is that any condensation occurring
in the vent pipe, which can be expected in particular in the
relatively cold section 66 running downwards, does not flow back to
the pipe 52. To keep the installation clean, the downward section
66 is positioned above the reservoir 50 in which the condensed
water is collected.
[0046] The installation is furthermore provided with a second vent
pipe 60, the function of which will now be clear after the above.
This pipe also runs up to a high level that is above the highest
level that can be reached by the water in the installation and is
then provided with a section 67 running downwards. This section 67
is oriented towards the reservoir 50. The pipe 60 is preferably
coupled to the hot water pipe 54 at the highest point of the
latter.
[0047] A separate flow meter is not used in the installation
according to FIG. 4 because, by virtue of the vent pipes, such a
calm flow of water through the various pipes is achieved that
activation of the pump for a predetermined period is sufficient to
supply a predetermined quantity of hot water. A flow meter is a
relatively expensive component that is susceptible to malfunction
and that has thus become superfluous by virtue of the measures
according to the invention.
* * * * *