U.S. patent application number 16/804728 was filed with the patent office on 2020-09-03 for electronic continuous-flow heater and method for operating such a heater.
The applicant listed for this patent is GERDES HOLDING GmbH & Co. KG. Invention is credited to Christian Koch.
Application Number | 20200278134 16/804728 |
Document ID | / |
Family ID | 1000004715600 |
Filed Date | 2020-09-03 |
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United States Patent
Application |
20200278134 |
Kind Code |
A1 |
Koch; Christian |
September 3, 2020 |
ELECTRONIC CONTINUOUS-FLOW HEATER AND METHOD FOR OPERATING SUCH A
HEATER
Abstract
An electronic continuous-flow heater for heating a liquid
includes an electrically heatable heating channel arrangement with
at least one electric heating element, an electronic control system
including at least one microprocessor configured to electrically
control the heating element, and a display device connected by
means of the electronic control system. The display device is
designed as a bistable digital display such that the display
content remains visible even in the absence of the display supply
voltage of the display device.
Inventors: |
Koch; Christian; (Wendisch
Evern, DE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
GERDES HOLDING GmbH & Co. KG |
Luneburg |
|
DE |
|
|
Family ID: |
1000004715600 |
Appl. No.: |
16/804728 |
Filed: |
February 28, 2020 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
F24H 2240/01 20130101;
F24H 1/103 20130101; F24H 9/2028 20130101 |
International
Class: |
F24H 9/20 20060101
F24H009/20; F24H 1/10 20060101 F24H001/10 |
Foreign Application Data
Date |
Code |
Application Number |
Feb 28, 2019 |
EP |
19160106.1 |
Claims
1. An electronic continuous-flow heater for heating a liquid,
comprising an electrically heatable heating channel arrangement
with at least one electric heating element; an electronic control
system, comprising at least one microprocessor, which is configured
to electrically control the heating element; a display device
connected by means of the electronic control system, wherein the
display device is designed as a bistable digital display, such that
display content remains visible even in the absence of a display
supply voltage of the display device.
2. The continuous-flow heater according to claim 1, wherein a
display surface of the display device is formed by an electronic
paper.
3. The continuous-flow heater according to claim 1, wherein the
electronic control system has at least one electrical energy
storage device for buffering an operating voltage of the electronic
control system and the electronic control system has an
undervoltage detection circuit for detecting an undervoltage of the
mains and/or heating element voltage.
4. The continuous-flow heater according to claim 3, wherein the
electronic control system is configured to cause the display device
to output an undervoltage message in the event that an undervoltage
is detected by the undervoltage detection circuit.
5. A method for operating an electronic continuous-flow heater for
heating a liquid, wherein the continuous-flow heater comprises an
electrically heatable heating channel arrangement with at least one
electric heating element, an electronic control system comprising
at least one microprocessor, and a display device connected by
means of the electronic control system, the method comprising the
step of: electrically controlling the at least one electric heating
element by the electronic control system; and controlling the
display device, as a bistable digital display, by the electronic
control system, such that the display content remains visible even
in the absence of the display supply voltage of the display
device.
6. The method according to claim 5, further comprising: buffering
of the operating voltage of the electronic control system by the
electronic control system; and detecting an undervoltage of the
mains and/or heating element voltage by an undervoltage detection
circuit of the electronic control system.
7. The method according to claim 6, further comprising causing, by
the electronic control system, the display device to output an
undervoltage message in the event that an undervoltage is detected
by the undervoltage detection circuit.
8. The method according to claim 5, further comprising causing the
control device to write a display content for identifying a
technical test, which is carried out on the continuous-flow heater,
on the display device at the factory before the continuous-flow
heater is disconnected from the power supply after the test has
been completed.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims priority from Application No. EP
19160106.1 filed Feb. 28, 2019, the entire content of which is
incorporated herein by reference.
FIELD OF THE INVENTION
[0002] The present invention relates to an electronic
continuous-flow heater for heating a liquid, comprising an
electrically heatable heating channel arrangement with at least one
electric heating element, an electronic control system, comprising
at least one microprocessor, which is configured to electrically
control the heating element, and a display device connected by
means of the electronic control system. The invention further
relates to a method for operating such an electronic
continuous-flow heater.
BACKGROUND OF THE INVENTION
[0003] A control and safety device for a continuous-flow heater is
known from document DE 44 16 798 A1. It discloses control means,
provided with voltage monitoring means, which detect an overvoltage
or undervoltage of the supply voltage in the known manner. The
voltage monitoring means are also connected to the RESET input of
the microcontroller to cause the control means to reset when a
threshold value of the supply voltage is detected.
[0004] Although the control means or the electronic control system
are reset in this way to a defined state in the event that
undervoltage occurs, when performing a reset of the electronic
control system, any display or display device connected will also
regularly perform a reset and thus lose the display content
previously displayed. After such an undervoltage event has
occurred, it is no longer possible for the user, operator or the
specialist staff to see afterwards the reason for which a reset was
performed or why the continuous-flow heater is not in a functional
state.
SUMMARY OF THE INVENTION
[0005] It is therefore the object of the present invention to
propose a continuous-flow heater which displays information about
the respective device status even when it is without power or mains
voltage. The object is also to provide a continuous-flow heater
which, in the event of undervoltage, provides details of the
undervoltage and/or overvoltage fault event that has occurred. The
object is further to propose a corresponding method for operating
such a continuous-flow heater.
[0006] The object is achieved by an arrangement with the features
referred to hereinbefore in that the display device is designed as
a bistable digital display, such that the display content remains
visible even in the absence of the display supply voltage of the
display device. Advantageously, it is thus achieved that the
display device of the continuous-flow heater according to the
invention always indicates the display content even when it is in
the de-energised state or is without supply voltage. In addition,
it is possible in this manner for the user and/or the specialist
staff to see on the continuous-flow heater that an undervoltage has
occurred. In this way, such an error status can always be seen
directly from the display content of the display device,
irrespective of whether or not the continuous-flow heater is being
properly supplied with mains voltage. According to an alternative
embodiment of the invention, the display device is also designed to
indicate display contents in shades of grey or in colour. In this
case, the display device is configured in each case such that the
display content is retained even when the display device is in the
de-energised state.
[0007] One advantageous development of the invention is
characterised in that the display surface of the display device is
formed by an electronic paper. This has the advantage that the
display device only has to be written on if the relevant display
content is to change. In addition, the display content most
recently written on the display device remains visible even if the
display device is no longer supplied with the display supply
voltage.
[0008] According to an advantageous development, it is provided
that the electronic control system has at least one electrical
energy storage device for buffering the operating voltage of the
electronic control system and the electronic control system has an
undervoltage detection circuit for detecting an undervoltage of the
mains and/or heating element voltage. Advantageously, the operating
voltage of the electronic control system is thus maintained, at
least temporarily, even when an undervoltage occurs, such that it
is possible to write a display content on the display device which
provides information about the type of undervoltage that has
occurred or the type of error. Furthermore, the electronic control
system can thus be brought into a defined state before the supply
voltage of the electronic control system finally breaks down.
[0009] A preferred embodiment of the invention is characterised in
that the electronic control system is configured to cause the
display device to output an undervoltage message in the event that
an undervoltage is detected by the undervoltage detection circuit.
This has the advantage that each undervoltage event can be seen on
the display device of the continuous-flow heater even when said
continuous-flow heater is in the de-energised state.
[0010] The object is further achieved by a corresponding method
with the features referred to hereinbefore in that the display
device, as a bistable digital display, is controlled by the control
device, such that the display content remains visible even in the
absence of the display supply voltage of the display device.
[0011] According to an advantageous embodiment of the invention,
the operating voltage of the electronic control system is buffered
by the electronic control system and an undervoltage of the mains
and/or heating element voltage is detected by an undervoltage
detection circuit of the electronic control system.
[0012] An advantageous embodiment is characterised in that the
electronic control system causes the display device to output an
undervoltage message in the event that an undervoltage is detected
by the undervoltage detection circuit.
[0013] According to a further advantageous embodiment, it is
provided to cause the control device to write a display content for
identifying a technical test, which is carried out on the
continuous-flow heater, on the display device at the factory before
the continuous-flow heater is disconnected from the power supply
after the test has been completed. In this way, it can be seen from
the display device, particularly in the de-energised state of the
continuous-flow heater, whether the continuous-flow heater has
successfully passed the required technical function test at the
factory. Furthermore, it can be seen from this that the device in
question is new.
[0014] The advantages associated with the method according to the
invention have already been explained in detail in connection with
the continuous-flow heater according to the invention, to which
reference is therefore made here.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] FIG. 1 is a block diagram of the electronic control system
of the continuous-flow heater according to the invention;
[0016] FIG. 2 is a flow chart of the mode of operation of the
electronic control system or the method according to the
invention;
[0017] FIG. 3 is an example of a first display content;
[0018] FIG. 4 is an example of a second display content; and
[0019] FIG. 5 is an example of a third display content.
DETAILED DESCRIPTION OF THE INVENTION
[0020] FIG. 1 shows a block diagram of the electronic control
system of the continuous-flow heater according to the invention.
The continuous-flow heater, which is not shown in the drawing,
comprises an electrically heatable heating channel arrangement with
at least one electric heating element which is preferably
configured as a bare wire heating coil. The electronic control
system comprises at least one microprocessor 10 which is configured
to electrically control the heating element. For this purpose, the
control device is connected to power electronics 11 which are
configured to switch the electric heating element on or off as well
as to control its heat output. Such power electronics are
sufficiently well known and are therefore not to be explained in
greater detail here.
[0021] The electronic control system is electrically connected to a
display device 12. As shown in FIG. 1, the display device 12 is
preferably electrically connected to the microprocessor 10. In this
case, the display device 12 is designed as a bistable digital
display. Once a display content is written to the display by the
electronic control system, it remains visible in this way even in
the absence of the display supply voltage of the display device 12.
Thus, it is always only necessary to write on the display device 12
if a changed display content is to be displayed.
[0022] The display surface of the display device 12 is preferably
formed by an electronic paper. In other words, the display device
12 is designed as an e-paper display. The display device 12 is thus
designed as a passive display on which display contents, such as
texts and/or graphics are permanently displayed without requiring
the presence of the display supply voltage. Once a display content
is displayed, it stays there, even if there is no display supply
voltage present, until a new write access with differing display
content is made by the electronic control system.
[0023] Advantageously, the electronic control system has at least
one electrical energy storage device 13 for buffering the operating
voltage of the electronic control system. The energy storage device
13 preferably comprises at least one supercap or ultracap. If any
undervoltages of the mains voltage occur or if a phase fails, the
energy storage device 13 serves as an intermediate storage device
to supply the electronic control system with power for a sufficient
length of time so that it can still carry out necessary control
steps before the operating voltage of the electronic control system
also becomes too low.
[0024] The electronic control system also comprises an undervoltage
detection circuit for registering or detecting an undervoltage of
the mains and/or heating element voltage. For this purpose, the
microprocessor 10 of the control circuit is connected via an
electrical line 14 to the power electronics which provide the
microprocessor 10 with a signal to query the mains and/or heating
element voltage. The line 14 and line 15 shown in FIG. 1 are
intended to symbolise the connection of the said components to each
other. The lines 14, 15 may be executed physically as electrical
signal lines or as a bus system.
[0025] The electronic control system is further configured to cause
the display device to output an undervoltage message in the event
that an undervoltage is detected by the undervoltage detection
circuit. The intention is to explain below the sequence during
detection of a/the undervoltage based on the flow chart in FIG. 2.
If the undervoltage detection circuit detects in step 15 that the
mains and/or supply voltage of the power electronics is lower than
a specified minimum voltage, then the voltage supply of the control
circuit, including the microprocessor 10 and the display device 12,
is first ensured via the energy storage device 13. The energy
storage device 13 optionally comprises necessary switching
components to automatically switch over to a supply by the energy
storage device 13 if the regular supply voltage of the electronic
control system fails. This changeover takes place in step 16.
[0026] In step 17, the display device 12 is written on with a
display content which informs about the type of undervoltage. If
the undervoltage detection circuit detects an undervoltage or a
failure of the mains phases, the display content shown in FIG. 3,
for example, is written on the display device 12. If the
undervoltage detection circuit detects an undervoltage of the
supply voltage of the heating element, the display content shown in
FIG. 4, for example, is outputted by the display device 12.
[0027] Further preferably, the microprocessor 10 and the display
device 12 are then put into a "hibernation mode" in step 18.
[0028] The method according to the invention has already been well
documented in connection with the previously described device
according to the invention, such that only selected aspects of the
method according to the invention will be enlarged upon below to
avoid repetitions.
[0029] The method according to the invention is used to operate the
electronic continuous-flow heater previously described. Electrical
control of the at least one electric heating element takes place by
the control device. The display device 12 is controlled as a
bistable digital display by the control device. This means that the
microprocessor 10 only writes a display content on the display
device 12 once in each case, since the display device
12--irrespective of whether or not it is supplied with the display
supply voltage--retains the display content written once by the
microprocessor. The display content thus always remains visible
even in the absence of the display supply voltage of the display
device 12.
[0030] Once the continuous-flow heater has passed all the necessary
tests for technical function and quality assurance on a test rig in
the production line, the third display content shown in FIG. 5 is
preferably written on the display device 12 at the factory. In
other words, the control device is caused to write a display
content, namely the said third display content, for identifying a
technical test, which is carried out on the continuous-flow heater,
on the display device 12 at the factory before the continuous-flow
heater is disconnected from the power supply after the test has
been completed. Advantageously, the said display content is
retained even in the de-energised state. When the continuous-flow
heater is removed from its packaging, the fitter can immediately
read from the display device 12 that he has received a new device
that has been tested and is in perfect condition. The control
device is further preferably designed to display this third display
content by the display device 12 only after successful performance
of the said tests. After initial commissioning, this third display
content is not displayed in any other operating state.
* * * * *