EP2359071A2 - Insert for a flow through heater - Google Patents
Insert for a flow through heaterInfo
- Publication number
- EP2359071A2 EP2359071A2 EP09756061A EP09756061A EP2359071A2 EP 2359071 A2 EP2359071 A2 EP 2359071A2 EP 09756061 A EP09756061 A EP 09756061A EP 09756061 A EP09756061 A EP 09756061A EP 2359071 A2 EP2359071 A2 EP 2359071A2
- Authority
- EP
- European Patent Office
- Prior art keywords
- flow
- heater
- liquid
- insert
- duct
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Withdrawn
Links
- 239000007788 liquid Substances 0.000 claims abstract description 171
- 238000000034 method Methods 0.000 claims abstract description 12
- 238000010438 heat treatment Methods 0.000 claims description 31
- 238000007789 sealing Methods 0.000 claims description 10
- 230000008569 process Effects 0.000 abstract description 6
- 230000001603 reducing effect Effects 0.000 abstract description 5
- 238000001514 detection method Methods 0.000 description 12
- 238000013461 design Methods 0.000 description 10
- 235000015114 espresso Nutrition 0.000 description 5
- 230000008901 benefit Effects 0.000 description 3
- 230000009467 reduction Effects 0.000 description 3
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 3
- 235000013361 beverage Nutrition 0.000 description 2
- 235000013353 coffee beverage Nutrition 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 238000005259 measurement Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 241000894006 Bacteria Species 0.000 description 1
- 241000533293 Sesbania emerus Species 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
- 238000005485 electric heating Methods 0.000 description 1
- 235000013350 formula milk Nutrition 0.000 description 1
- 238000003825 pressing Methods 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 230000004044 response Effects 0.000 description 1
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24H—FLUID HEATERS, e.g. WATER OR AIR HEATERS, HAVING HEAT-GENERATING MEANS, e.g. HEAT PUMPS, IN GENERAL
- F24H1/00—Water heaters, e.g. boilers, continuous-flow heaters or water-storage heaters
- F24H1/10—Continuous-flow heaters, i.e. heaters in which heat is generated only while the water is flowing, e.g. with direct contact of the water with the heating medium
- F24H1/12—Continuous-flow heaters, i.e. heaters in which heat is generated only while the water is flowing, e.g. with direct contact of the water with the heating medium in which the water is kept separate from the heating medium
- F24H1/14—Continuous-flow heaters, i.e. heaters in which heat is generated only while the water is flowing, e.g. with direct contact of the water with the heating medium in which the water is kept separate from the heating medium by tubes, e.g. bent in serpentine form
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24H—FLUID HEATERS, e.g. WATER OR AIR HEATERS, HAVING HEAT-GENERATING MEANS, e.g. HEAT PUMPS, IN GENERAL
- F24H1/00—Water heaters, e.g. boilers, continuous-flow heaters or water-storage heaters
- F24H1/10—Continuous-flow heaters, i.e. heaters in which heat is generated only while the water is flowing, e.g. with direct contact of the water with the heating medium
- F24H1/12—Continuous-flow heaters, i.e. heaters in which heat is generated only while the water is flowing, e.g. with direct contact of the water with the heating medium in which the water is kept separate from the heating medium
- F24H1/14—Continuous-flow heaters, i.e. heaters in which heat is generated only while the water is flowing, e.g. with direct contact of the water with the heating medium in which the water is kept separate from the heating medium by tubes, e.g. bent in serpentine form
- F24H1/142—Continuous-flow heaters, i.e. heaters in which heat is generated only while the water is flowing, e.g. with direct contact of the water with the heating medium in which the water is kept separate from the heating medium by tubes, e.g. bent in serpentine form using electric energy supply
-
- A—HUMAN NECESSITIES
- A47—FURNITURE; DOMESTIC ARTICLES OR APPLIANCES; COFFEE MILLS; SPICE MILLS; SUCTION CLEANERS IN GENERAL
- A47J—KITCHEN EQUIPMENT; COFFEE MILLS; SPICE MILLS; APPARATUS FOR MAKING BEVERAGES
- A47J31/00—Apparatus for making beverages
- A47J31/44—Parts or details or accessories of beverage-making apparatus
- A47J31/54—Water boiling vessels in beverage making machines
- A47J31/542—Continuous-flow heaters
- A47J31/545—Control or safety devices
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24H—FLUID HEATERS, e.g. WATER OR AIR HEATERS, HAVING HEAT-GENERATING MEANS, e.g. HEAT PUMPS, IN GENERAL
- F24H15/00—Control of fluid heaters
- F24H15/20—Control of fluid heaters characterised by control inputs
- F24H15/212—Temperature of the water
- F24H15/219—Temperature of the water after heating
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24H—FLUID HEATERS, e.g. WATER OR AIR HEATERS, HAVING HEAT-GENERATING MEANS, e.g. HEAT PUMPS, IN GENERAL
- F24H9/00—Details
- F24H9/0005—Details for water heaters
- F24H9/001—Guiding means
- F24H9/0015—Guiding means in water channels
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24H—FLUID HEATERS, e.g. WATER OR AIR HEATERS, HAVING HEAT-GENERATING MEANS, e.g. HEAT PUMPS, IN GENERAL
- F24H9/00—Details
- F24H9/20—Arrangement or mounting of control or safety devices
- F24H9/2007—Arrangement or mounting of control or safety devices for water heaters
- F24H9/2014—Arrangement or mounting of control or safety devices for water heaters using electrical energy supply
- F24H9/2028—Continuous-flow heaters
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01K—MEASURING TEMPERATURE; MEASURING QUANTITY OF HEAT; THERMALLY-SENSITIVE ELEMENTS NOT OTHERWISE PROVIDED FOR
- G01K1/00—Details of thermometers not specially adapted for particular types of thermometer
- G01K1/14—Supports; Fastening devices; Arrangements for mounting thermometers in particular locations
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01K—MEASURING TEMPERATURE; MEASURING QUANTITY OF HEAT; THERMALLY-SENSITIVE ELEMENTS NOT OTHERWISE PROVIDED FOR
- G01K13/00—Thermometers specially adapted for specific purposes
- G01K13/02—Thermometers specially adapted for specific purposes for measuring temperature of moving fluids or granular materials capable of flow
Abstract
When feedback loop control is used for controlling a temperature of liquid at an outlet (5) of a flow through heater, a volume of an ineffective portion (4) of the flow through heater at the outlet (5) constitutes a dead volume which causes a delay in the feedback process. In order to minimize the delay, an insert (6) is applied, which serves for reducing the dead volume by occupying most of this volume. In a practical case, the insert (6) comprises a duct system (12) for conveying liquid from a liquid conveying conduit (2) of the flow through heater to an outlet (10) of the insert (6). Preferably, a volume of such a liquid conveying duct system (12) is relatively small, so that the presence of the duct system (12) in the insert (6) does not spoil the dead volume reducing effect of the application of the insert (6).
Description
Insert for a flow through heater
FIELD OF THE INVENTION
The present invention relates to a device for heating liquid, comprising a flow through heater having a conduit for conveying liquid and means for heating the liquid while flowing through the conduit; and means for detecting a temperature of liquid at an outlet of the flow through heater, which are part of a device for controlling a temperature of liquid at the outlet of the flow through heater.
Furthermore, the present invention relates to a method for increasing accuracy in controlling a temperature of liquid at an outlet of a flow through heater.
BACKGROUND OF THE INVENTION
In many types of devices, there is a need for means which are capable of heating a quantity of liquid to be used during operation of the device. For example, in a device which is suitable for making hot coffee, a quantity of water is heated before being made to flow through a quantity of ground coffee beans. For the purpose of heating a liquid such as water, many devices are equipped with a boiler, i.e. a device having a container for containing a quantity of liquid, and heating means which are associated with the container, and which serve for heating liquid that is present inside the container. As soon as the temperature of the liquid is at a desired level, the liquid may be drawn from the boiler and used for its intended purpose. However, the application of a boiler has some notable disadvantages, and therefore, another way of heating liquid has been developed, which involves the application of a flow through heater, i.e. a device having a conduit for conveying liquid and means for heating the liquid while flowing through the conduit. In practical embodiments of the flow through heater, electric heating elements are arranged around the liquid conveying conduit. Some important advantages of applying a flow through heater are that the heating process of the liquid is performed almost instantaneously, so that there is hardly any waiting time, that less energy is needed when compared to the application of a boiler, and that the flow through heater is not only suitable to be used as a substitute of the boiler, but also in high pressure systems such as espresso devices.
For the purpose of controlling a temperature of liquid at an outlet of the flow through heater, a feed back control loop is likely to be used. However, in practice, it appears to be difficult or even impossible to meet high demands in respect of the outlet temperature as mentioned. In other words, it appears to be difficult or even impossible to control the operation of the flow through heater on the basis of a detection of the outlet temperature in a sufficiently accurate manner.
SUMMARY OF THE INVENTION
It is an object of the present invention to optimize the feedback control loop in a device comprising a flow through heater and the feedback control loop for controlling the outlet temperature. The object is achieved by providing an insert which is partially inserted in the liquid conveying conduit of the flow through heater, at an outlet side of the flow through heater, wherein a portion of the insert that is located inside the liquid conveying conduit of the flow through heater is occupying at least a substantial portion of space which is present in a portion of the liquid conveying conduit which is not directly associated with the heating means of the flow through heater.
According to an insight underlying the present invention, the difficulties in controlling the outlet temperature are caused by a delay in the feedback process, which is related to the usual design of the flow through heater. In particular, in this design, the liquid conveying conduit and the heating elements are arranged with respect to each other in such a way that the conduit is protruding over some length with respect to the heating elements, at both an inlet side and an outlet side of the flow through heater. Hence, when the temperature of liquid is detected at the outlet of the flow through heater, which is in fact the outlet of the conduit, there is a delay caused by the fact that the liquid has first traveled through a length of the conduit which is not directly associated with heating elements before reaching the place where the detection takes place. In the following, this phenomenon will be referred to as the presence of dead volume in the flow through heater, and the portion of the conduit which is not directly associated with heating elements is referred to as ineffective portion of the flow through heater. With respect to the dead volume and the associated delay time, it is noted that the larger the dead volume, the harder it is to realize a desired average outlet temperature under all circumstances. This is especially apparent when the dead volume is significant when compared to a total volume of the flow through heater, which is the case in flow through heaters which are suitable to be used in espresso devices, for example. In general, the
longer the delay time, the slower the response of a feedback control loop, and the earlier an occurrence of instability. Therefore, a longer delay time leads to a restriction of the applicability of the flow through heater. For example, an application in an espresso device is practically not possible, as such an application requires a fast responding feedback control loop.
In many applications, it is important to have the lowest possible manufacturing costs. Therefore, in many cases, it is not a feasible option to change the design of the flow through heater in order to solve the above-sketched problems. Instead, another solution is needed on the basis of the assumption that conventional flow through heaters are applied. The present invention provides such solution by proposing the application of an insert which is partially inserted in the liquid conveying conduit of the flow through heater, at an outlet side of the flow through heater, wherein a portion of the insert that is located inside the liquid conveying conduit of the flow through heater is occupying at least a substantial portion of the dead volume. When the insert according to the present invention is applied, it is achieved that the dead volume is significantly reduced. This is due to the fact that the portion of the insert that is located inside the liquid conveying conduit of the flow through heater fills up the dead volume. In many practical cases, this portion of the insert is longer than necessary for keeping the insert in place in the liquid conveying conduit, as seen in a flow direction of liquid in the flow through heater.
Due to the reduction of the dead volume which is achieved by applying the insert as mentioned, the delay time in detecting the outlet temperature of liquid is significantly reduced, as an advantageous result of which controlling the outlet temperature can be performed more effectively and accurately. According to the present invention, it does not take a modification of the design of the flow through heater, nor does it take an upgrade of the components used in the temperature controlling process to achieve such an advantageous result, but it only takes the application of a simple additional component, namely the insert.
In order to reduce the dead volume of the ineffective portion of the flow through heater as much as possible, and in order to have a secure arrangement of the insert in the conduit, it is preferred if only little play is present between the inner surface of the liquid conveying conduit of the flow through heater and the outer surface of the portion of the insert that is located inside the liquid conveying conduit.
In a practical case, the insert comprises a duct system for conveying liquid from the liquid conveying conduit of the flow through heater to an outlet of the insert. In that case, the duct(s) of the liquid conveying duct system of the insert serve for transporting the liquid through the ineffective portion of the flow through heater. Preferably, a diameter of the duct(s) of such a liquid conveying duct system is significantly smaller than a diameter of the liquid conveying conduit of the flow through heater at the outlet of the flow through heater, so that the volume of the duct(s) is much smaller than the volume of the ineffective portion of the flow through heater, and the dead volume reducing effect of the application of the insert may be optimal. The insert according to the invention may comprise a duct which is extending from an outer surface of the insert to the liquid conveying duct system, in a portion of the insert that is located outside of the liquid conveying conduit of the flow through heater, wherein the means for detecting a temperature of liquid at the outlet of the flow through heater are associated with this duct. Preferably, this duct is located as close as possible to the end of the liquid conveying duct of the flow through heater, so that the detection of the outlet temperature may take place at a location which is as close as possible to the end of the liquid conveying duct, and the length over which a dead volume exists, albeit a relatively small dead volume, is kept to a minimum.
With respect to the liquid conveying duct system which may be part of the insert it is noted that this duct system may comprise at least two ducts which are oriented at an angle with respect to each other. In an advantageous design, the duct system comprises at least one duct for letting in liquid to the duct system, wherein this at least one inlet duct is oriented substantially perpendicular to a flow direction of liquid in the flow through heater, and is extending from one side of the insert to another; and a duct for letting out liquid from the duct system, wherein this outlet duct is oriented substantially parallel to the flow direction of liquid in the flow through heater, and wherein the at least one inlet duct and the outlet duct are connected to each other.
An advantage of applying a design of the liquid conveying duct system of the insert in which the at least one inlet duct is oriented at an angle to the outlet duct, and in which the inlet duct is extending from one side of the insert to another is that a situation in which liquid might remain at an outlet of the insert is prevented. The inlet duct functions as a kind of shortcut, and liquid cannot reach the outlet of the insert unless a sucking and/or pressing force is applied. Furthermore, it is possible to create various inlet passages when the concept of having an angle between the inlet duct(s) and the outlet duct is applied, so that
mixing of the liquid is realized at the connection of the inlet duct(s) to the outlet duct, which results in an even more accurate temperature detection.
In a practical embodiment, in particular an embodiment in which the insert comprises a liquid conveying duct system, the device according to the present invention may further comprise means for sealing a space between an outer surface of a portion of the insert that is located inside the liquid conveying conduit of the flow through heater and an inner surface of the liquid conveying conduit. By using suitable sealing means, leakage of liquid from the liquid conveying conduit through a (narrow) space between the outer surface of the insert and the inner surface of the conduit is prevented. Naturally, the sealing means, which may comprise an O-ring or the like, are located behind the inlet(s) of the liquid conveying duct system of the insert as seen in the flow direction of liquid in the flow through heater.
Many of the above-described aspects of the present invention appear from the insert when being considered separately. In that case, these aspects are worded as follows.
The insert is described in general as an insert which is intended for use in the device for heating liquid as described in the foregoing, comprising:
- an end portion which is suitable to be inserted in a conduit for conveying liquid, in particular a liquid conveying conduit which is part of a flow through heater further having means for heating liquid while flowing through the conduit; and
- a duct system for conveying liquid through the insert, wherein a diameter of the duct(s) of the liquid conveying duct system is significantly smaller than an outer diameter of the end portion.
In the insert according to the present invention, it is advantageous if the liquid conveying duct system comprises at least two ducts which are oriented at an angle with respect to each other. Preferably, in that case, the liquid conveying duct system comprises at least one duct for letting in liquid to the duct system, wherein this at least one inlet duct is oriented substantially perpendicular to an axial direction of the insert, i.e. a longitudinal direction of the insert, and is extending from one side of the insert to another; and a duct for letting out liquid from the duct system, wherein this outlet duct is oriented substantially parallel to the axial direction of the insert, and wherein the at least one inlet duct and the outlet duct are connected to each other.
For the purpose of allowing temperature detection of liquid at the inside of the insert, it is advantageous if the insert further comprises a duct which is extending from an outer surface of the insert to the liquid conveying duct system, in another portion of the insert than the end portion which is suitable to be inserted in a conduit for conveying liquid.
The sealing means which are preferably used for avoiding leakage of liquid from the liquid conveying conduit of the flow through heater may be provided as (a) component(s) of the insert. In such a case, the insert further comprises means such as an O- ring which are suitable to be used for sealing a space between two surfaces, wherein these sealing means are located at the end portion which is suitable to be inserted in a conduit for conveying liquid.
Besides a device for heating a liquid as described in the foregoing, the present invention also provides a method for increasing accuracy at an outlet of a flow through heater having a conduit for conveying liquid and means for heating the liquid while flowing through the conduit, wherein at least a substantial portion of space which is present in a portion of the liquid conveying conduit of the flow through heater which is not directly associated with the heating means of the flow through heater is filled up by providing an insert and introducing at least a portion of the insert in the liquid conveying conduit into the flow through heater, at an outlet side of the flow through heater. Preferably, when the method according to the present invention is carried out, only little play is allowed between an inner surface of the liquid conveying conduit of the flow through heater and an outer surface of the portion of the insert that is inserted in the liquid conveying conduit.
The insert which is applied when the method according to the present invention is carried out, may be the insert as defined in the foregoing, or any other suitable insert, provided that a reduction of the dead volume can be achieved through an occupation of this volume, and that a flow of liquid is not blocked.
The above-described and other aspects of the present invention will be apparent from and elucidated with reference to the following detailed description of an embodiment of the insert according to the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will now be explained in greater detail with reference to the figures, in which equal or similar parts are indicated by the same reference signs, and in which: figure 1 diagrammatically shows a flow through heater; figure 2 diagrammatically shows a portion of a flow through heater and an insert according to the present invention;
figures 3 and 4 show views of two longitudinal sections of an end of a liquid conveying conduit of the flow through heater and the insert.
DETAILED DESCRIPTION OF EMBODIMENTS Figure 1 diagrammatically shows a flow through heater 1 as known in the art.
In general, the flow through heater 1 comprises a conduit 2 for conveying liquid and heating elements 3 which are arranged such as to closely surround the liquid conveying conduit 2. In most cases, a cross-sectional area of the liquid conveying conduit has a circular shape, which does not alter the fact that other shapes are possible as well. In figure 1, it can clearly be seen that not all of the length of the liquid conveying conduit 2 is covered by the heating elements 3. At both an inlet side and an outlet side of the flow through heater 1, a length 4 of the liquid conveying conduit 2 is not directly associated with the heating elements 3. These lengths 4 are referred to as ineffective portions 4 of the flow through heater 1. During operation of the flow through heater 1, a liquid such as water is made to flow through the liquid conveying conduit 2, while the heating elements 3 are operated for supplying heat to the liquid in order to achieve an increase of the temperature of the liquid. Three important factors in achieving a desired temperature of the liquid at an outlet 5 of the flow through heater 1 are the initial temperature of the liquid, the flow rate, and the supply of heat. In order to check whether an actual outlet temperature of liquid is within a desired range, and to determine whether parameters of the flow through heating process such as a power supply to the heating elements 3 of the flow through heater 1 need to be adjusted, it is common practice to have a feedback control loop, wherein the outlet temperature is detected and used as a basis for possible adjustments. However, due to the presence of an ineffective portion 4 at the outlet of the liquid conveying conduit 2 of the flow through heater 1, there is a delay in the feedback control loop, which has a negative influence on the accuracy of the temperature controlling process.
The delay in the feedback control loop is directly related to the volume of the ineffective portion 4 at the outlet of the flow through heater 1, which is referred to as dead volume. For example, when the ineffective portion 4 has a length of 2 cm, an inner diameter of the liquid conveying conduit 2 is 1 cm, the flow rate is 5 ml/s and the outlet temperature is detected at the outlet 5 of the flow through heater 1, the delay time appears to be 0.314 s. This value is found by determining the dead volume, and dividing the dead volume by the flow rate. The dead volume equals pi * r2 * 1 = pi * 0.52 * 2 = 1.57 ml, wherein r stands for
the inner radius of the liquid conveying conduit 2, and wherein 1 stands for the length of the ineffective portion 4 of the flow through heater 1. Hence, the delay time equals 1.57 / 5 = 0.314 s. For example, for applications related to making espresso, a dead volume of 1.57 ml is significant compared to a total volume. Therefore, in such cases, the dead volume has a significant influence on a final temperature of the beverage.
In order to minimize the delay in the feedback control loop, the present invention proposes measurements to make the dead volume as small as possible. These measurements involve the application of an insert 6 which is partially inserted in the liquid conveying conduit 2 of the flow through heater 1, as is illustrated by figure 2 in which the insert 6 is indicated by dashed lines. Furthermore, figure 2 indicates an appropriate position of a temperature sensor 7, which is in a portion of the insert 6 right outside of the flow through heater 1. The insert 6 is preferably designed such as to remove as much of the dead volume as possible, while at the same time allowing for a required flow of liquid. The design of the insert 6 will be further elucidated on the basis of figures 3 and 4, in which longitudinal sections of the insert 6 are shown, as well as a portion of the liquid conveying conduit 2 of the flow through heater 1 , in which the insert 6 is partially inserted.
The example of the insert 6 as shown in figures 3 and 4 comprises three portions. A first portion 8 is an end portion which is suitable to be located inside the ineffective portion 4 of the flow through heater 1. Hence, an outer diameter of this end portion 8 of the insert 6 is smaller than an inner diameter of the liquid conveying conduit 2 of the flow through heater 1. A second portion 9 is another end portion which allows for connection of a hose or the like to the insert 6, and has an outlet 10 for the liquid at its free end. A third portion 11 is an intermediate portion which is intended to be arranged such as to abut against an end of the liquid conveying conduit 2 of the flow through heater 1. Hence, an outer diameter of this intermediate portion 11 of the insert 6 is larger than an inner diameter of the liquid conveying conduit 2 of the flow through heater 1.
Inside the insert 6, a duct system 12 for conveying liquid through the insert 6 is arranged. At an inlet side, i.e. a side closest to the flow through heater 1, the duct system 12 comprises two ducts 13a, 13b which are extending in a radial direction of the insert 6, i.e. a direction perpendicular to a flow direction of liquid in the flow through heater 1. These ducts 13 a, 13b serve for letting in liquid to the insert 6 and conveying the liquid to a central location inside the insert 6 where the ducts 13a, 13b are crossing. Extending from this location to the outlet 10 of the insert 6, an outlet duct 14 is present inside the insert 6. For
sake of completeness, it is noted that the flow direction of liquid in the flow through heater 1 is indicated by means of arrows in the figures.
It should be clear that other designs than the above-described design of the liquid conveying duct system 12 of the insert 6 are possible within the scope of the present invention. For example, there could be a single, central duct extending through the insert 6. However, the configuration with the radially oriented inlet ducts 13a, 13b is preferred, as it is possible to avoid a situation in which liquid is not refreshed and remains at an outlet side of the insert 6 when this configuration is realized. This is important in view of the fact that a remaining quantity of liquid can be a source of bacteria growth. Furthermore, by letting in liquid from various sides of the insert 6, mixing of the liquid is achieved, which contributes to a smooth temperature detection.
Besides ducts 13 a, 13b, 14 for conveying liquid, the insert 6 has a duct 15 for accommodating one or more components or portions of components (now shown in figures 3 and 4) which are to be used in a process of detecting the outlet temperature of liquid. In the following, this duct 15 will be referred to as detection duct 5. The detection duct 15 is arranged in the intermediate portion 11 of the insert 6, and is extending from an outer surface of the insert 6 to the outlet duct 14, in order to allow free access of the detection component(s) to liquid flowing through the outlet duct 14. In the shown example, the detection duct 15 has a radial orientation in the insert 6, like the inlet ducts 13a, 13b. For the purpose of avoiding leakage of liquid from the liquid conveying conduit 2 of the flow through heater 1, sealing means are arranged between an inner surface of the conduit 2 and the outer surface of the insert 6, at a position behind the position where the inlet ducts 13a, 13b of the insert 6 are located. Within the scope of the present invention, any suitable type of sealing means may be applied. In the shown example, the sealing means comprise an O-ring 16 which is accommodated in a groove that is arranged in the outer surface of the insert 6.
Figures 3 and 4 show that the dimensions of the end portion 8 of the insert 6 which is suitable to be located inside the ineffective portion 4 of the flow through heater 1 are chosen such that only minimal space is present between an outer surface of this portion 8 of the insert 6 and the inner surface of the liquid conveying conduit 2 of the flow through heater 1 when the insert 6 is in its proper position. All in all, when the insert 6 is put in place at the outlet side of the flow through heater 1, most of the volume of the ineffective portion 4 of the flow through heater 1 is filled up, wherein the volume causing delay in the detection of the outlet temperature of liquid is no more than a volume which is the sum of the space which is
present between the outer surface of the inserted portion 8 of the insert 6 and the inner surface of the liquid conveying conduit 2 of the flow through heater 1, the volume of the inlet ducts 13a, 13b of the insert 6, and the volume of the outlet duct 14 between the connection to the inlet ducts 13a, 13b and the position of the detection duct 15. It is most advantageous if the diameters of the ducts 13a, 13b, 14 of the liquid conveying duct system 12 of the insert 6 are significantly smaller than the diameter of the liquid conveying conduit 2 of the flow through heater 1 at the outlet side of the flow through heater 1, so that the dead volume can actually be as small as possible. Due to the reduction of the dead volume of the ineffective portion 4 of the flow through heater 1, the present invention allows for an improved way of controlling the outlet temperature, which results in better performances of the devices in which the invention will be applied. Examples of such devices which are worthy of mention here are beverage making devices, in particular coffee devices and espresso devices of various types, including the drip filter type and the pad processing type, and baby milk devices. During a manufacturing process of a device in which the present invention is applied, a conventional flow through heater 1 is provided, wherein the dead volume at the outlet side of the flow through heater 1 is reduced by providing the insert 6 according to the present invention and introducing the end portion 8 of the insert 6 into the liquid conveying conduit 2 of the flow through heater 1.
It will be clear to a person skilled in the art that the scope of the present invention is not limited to the examples discussed in the foregoing, but that several amendments and modifications thereof are possible without deviating from the scope of the present invention as defined in the attached claims. While the present invention has been illustrated and described in detail in the figures and the description, such illustration and description are to be considered illustrative or exemplary only, and not restrictive. The present invention is not limited to the disclosed embodiments.
Variations to the disclosed embodiments can be understood and effected by a person skilled in the art in practicing the claimed invention, from a study of the figures, the description and the attached claims. In the claims, the word "comprising" does not exclude other steps or elements, and the indefinite article "a" or "an" does not exclude a plurality. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage. Any reference signs in the claims should not be construed as limiting the scope of the present invention.
The present invention can be summarized as follows. In a flow through heater 1 of common design, an effective portion and two ineffective portions 4 located at ends of the flow through heater 1 can be discerned, wherein the ineffective portions 4 are portions where a liquid conveying conduit 2 of the flow through heater 1 is not directly associated with heating means 3 of the flow through heater 1. When feedback loop control is used for controlling a temperature of liquid at an outlet 5 of the flow through heater 1, a volume of the ineffective portion 4 at the outlet 5 constitutes a dead volume which causes a delay in the feedback process, resulting in instability and inaccuracy of the temperature control. In order to prevent this, the delay should be minimized. Therefore, it is desired to detect the outlet temperature as quick as possible after the effective portion of the flow through heater 1 as seen in a flow direction of liquid in the flow through heater 1. This is realized by applying an insert 6 for reducing the dead volume by occupying most of this volume. In a practical case, the insert 6 comprises a duct system 12 for conveying liquid from the liquid conveying conduit 2 of the flow through heater 1 to an outlet 10 of the insert 6. Preferably, in such a case, a diameter of the duct(s) 13a, 13b, 14 of the liquid conveying duct system 12 is significantly smaller than a diameter of the liquid conveying conduit 2 of the flow through heater 1 at the outlet 5 of the flow through heater 1, so that a volume of the liquid conveying duct system 12 is relatively small, and the presence of the duct system 12 in the insert 6 does not spoil the dead volume reducing effect of the application of the insert 6.
Claims
1. Device for heating liquid, comprising:
- a flow through heater (1) having a conduit (2) for conveying liquid and means (3) for heating the liquid while flowing through the conduit (2);
- means (7) for detecting a temperature of liquid at an outlet (5) of the flow through heater (1), which are part of a device for controlling a temperature of liquid at the outlet (5) of the flow through heater (1); and
- an insert (6) which is partially inserted in the liquid conveying conduit (2) of the flow through heater (1), at an outlet side of the flow through heater (1), wherein a portion (8) of the insert (6) that is located inside the liquid conveying conduit (2) of the flow through heater (1) is occupying at least a substantial portion of space which is present in a portion (4) of the liquid conveying conduit (2) which is not directly associated with the heating means (3) of the flow through heater (1).
2. Device according to claim 1, wherein only little play is present between an inner surface of the liquid conveying conduit (2) of the flow through heater (1) and an outer surface of the portion (8) of the insert (6) that is located inside the liquid conveying conduit
(2).
3. Device according to claim 1, wherein the insert (6) comprises a duct system (12) for conveying liquid from the liquid conveying conduit (2) of the flow through heater (1) to an outlet (10) of the insert (6), and wherein a diameter of the duct(s) (13a, 13b, 14) of the liquid conveying duct system (12) is significantly smaller than a diameter of the liquid conveying conduit (2) of the flow through heater (1) at the outlet (5) of the flow through heater (1).
4. Device according to claim 3, wherein the liquid conveying duct system (12) of the insert (6) comprises at least two ducts (13a, 13b, 14) which are oriented at an angle with respect to each other.
5. Device according to claim 4, wherein the liquid conveying duct system (12) of the insert (6) comprises at least one duct (13a, 13b) for letting in liquid to the duct system (12), wherein this at least one inlet duct (13a, 13b) is oriented substantially perpendicular to a flow direction of liquid in the flow through heater (1), and is extending from one side of the insert (6) to another; and a duct (14) for letting out liquid from the duct system (12), wherein this outlet duct (14) is oriented substantially parallel to the flow direction of liquid in the flow through heater (1), and wherein the at least one inlet duct (13a, 13b) and the outlet duct (14) are connected to each other.
6. Device according to claim 3, wherein the insert (6) further comprises a duct
(15) which is extending from an outer surface of the insert (6) to the liquid conveying duct system (12), in a portion (11) of the insert (6) that is located outside of the liquid conveying conduit (2) of the flow through heater (1), and wherein the means (7) for detecting a temperature of liquid at the outlet (5) of the flow through heater (1) are associated with this duct (15).
7. Device according to claim 3, further comprising means (16) for sealing a space between an outer surface of a portion (8) of the insert (6) that is located inside the liquid conveying conduit (2) of the flow through heater (1) and an inner surface of the liquid conveying conduit (2).
8. Method for increasing accuracy in controlling a temperature of liquid at an outlet of a flow through heater (1) having a conduit (2) for conveying liquid and means (3) for heating the liquid while flowing through the conduit (2), wherein at least a substantial portion of space which is present in a portion (4) of the liquid conveying conduit (2) of the flow through heater (1) which is not directly associated with the heating means (3) of the flow through heater (1) is filled up by providing an insert (6) and introducing at least a portion (8) of the insert (6) into the liquid conveying conduit (2) of the flow through heater (1), at an outlet side of the flow through heater (1).
9. Method according to claim 8, wherein only little play is allowed between an inner surface of the liquid conveying conduit (2) of the flow through heater (1) and an outer surface of the portion (8) of the insert (6) that is inserted in the liquid conveying conduit (2).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| EP09756061A EP2359071A2 (en) | 2008-11-14 | 2009-11-11 | Insert for a flow through heater |
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| EP08169083 | 2008-11-14 | ||
| EP09756061A EP2359071A2 (en) | 2008-11-14 | 2009-11-11 | Insert for a flow through heater |
| PCT/IB2009/055013 WO2010055472A2 (en) | 2008-11-14 | 2009-11-11 | Insert for a flow through heater |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| EP2359071A2 true EP2359071A2 (en) | 2011-08-24 |
Family
ID=42170476
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| EP09756061A Withdrawn EP2359071A2 (en) | 2008-11-14 | 2009-11-11 | Insert for a flow through heater |
Country Status (8)
| Country | Link |
|---|---|
| US (1) | US20110217027A1 (en) |
| EP (1) | EP2359071A2 (en) |
| JP (1) | JP2012515891A (en) |
| KR (1) | KR20110095886A (en) |
| CN (2) | CN102317703A (en) |
| DE (1) | DE202009015187U1 (en) |
| RU (1) | RU2011123882A (en) |
| WO (1) | WO2010055472A2 (en) |
Families Citing this family (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP2407069A1 (en) | 2010-07-12 | 2012-01-18 | Bleckmann GmbH & Co. KG | Dynamic flow-through heater |
| ES2534083T3 (en) * | 2011-04-29 | 2015-04-17 | Nestec S.A. | Insert for use in a food preparation machine |
| CN104411218B (en) | 2012-05-15 | 2020-07-07 | 布莱克曼两合公司 | Beverage preparation device, flow-through heater apparatus and method of producing the same |
| CN105051461A (en) | 2013-04-02 | 2015-11-11 | 皇家飞利浦有限公司 | Electrochemical descaling by pulsed signal reversal |
| JP6363695B2 (en) | 2013-04-02 | 2018-07-25 | コーニンクレッカ フィリップス エヌ ヴェＫｏｎｉｎｋｌｉｊｋｅ Ｐｈｉｌｉｐｓ Ｎ．Ｖ． | Electrochemical scale removal by pulse signal inversion |
| CN203898082U (en) * | 2014-01-14 | 2014-10-29 | 宁波金阳光电热科技有限公司 | Pressure type liquid quick heater |
| CN104535206A (en) * | 2014-12-01 | 2015-04-22 | 江门市君盛实业有限公司 | Mounting structure of thermometer |
Family Cites Families (25)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US978808A (en) * | 1908-07-07 | 1910-12-13 | Simplex Electric Heating Co | Electric circulation water-heater. |
| US1513087A (en) * | 1922-03-29 | 1924-10-28 | Nat Electric Water Heater Comp | Electric heater |
| US3898428A (en) * | 1974-03-07 | 1975-08-05 | Universal Oil Prod Co | Electric in line water heating apparatus |
| DE2549619A1 (en) * | 1975-11-05 | 1977-05-12 | Zink Co John | Measurement of temperature of hot flowing gases - involves thermocouple surrounded by concentric thin walled tubes to protect against radiation loss |
| DE3116951C2 (en) * | 1981-04-29 | 1984-12-20 | Drägerwerk AG, 2400 Lübeck | Device for adding liquid anesthetics to the breathing gas to be supplied to the patient |
| US4604515A (en) * | 1984-10-16 | 1986-08-05 | Cmr Enterprises, Inc. | Tankless electric water heater with staged heating element energization |
| DE3810736A1 (en) * | 1988-03-30 | 1989-10-19 | Bentz & Sohn Melitta | CONTINUOUS HEATER, ESPECIALLY FOR A COFFEE OR TEA MACHINE |
| CH675819A5 (en) * | 1988-06-10 | 1990-11-15 | Nestle Sa | |
| US5415024A (en) * | 1992-12-16 | 1995-05-16 | Marathon Oil Company | Composition analyzer for determining composition of multiphase multicomponent fluid mixture |
| FR2721381B1 (en) * | 1994-06-20 | 1996-08-02 | Seb Sa | Device for producing hot water or steam. |
| US6078032A (en) * | 1998-08-07 | 2000-06-20 | Bmg Holdings, Llc | Hot water beverage maker with voltage transformer type water heating unit |
| US6459854B1 (en) * | 2000-01-24 | 2002-10-01 | Nestec S.A. | Process and module for heating liquid |
| NL1014601C2 (en) * | 2000-03-10 | 2001-09-11 | Ferro Techniek Bv | Heating element, liquid container and method for detecting temperature changes. |
| US20040146289A1 (en) * | 2001-04-20 | 2004-07-29 | Atsunobu Sakamoto | Electric water heater, liquid heater, steam generator |
| DE20120611U1 (en) * | 2001-12-20 | 2003-02-13 | Eichenauer Gmbh & Co Kg F | Heating system for a steam generator |
| GB2399527B (en) * | 2003-03-21 | 2005-08-31 | Pyrotek Engineering Materials | Continuous casting installation & process |
| FR2855359B1 (en) * | 2003-05-19 | 2005-07-01 | Seb Sa | DEVICE FOR HEATING A LIQUID FOR AN ELECTRICAL APPLIANCE, AN ELECTRICAL APPLIANCE EQUIPPED WITH SUCH A DEVICE. |
| EP1532905A1 (en) * | 2003-11-20 | 2005-05-25 | Steiner AG Weggis | Device for supplying hot water, steam or hot milk to a coffee machine |
| WO2005057090A1 (en) * | 2003-12-10 | 2005-06-23 | Matsushita Electric Industrial Co., Ltd. | Heat exchanger and cleaning device with the same |
| EP1634520A1 (en) * | 2004-09-13 | 2006-03-15 | Nestec S.A. | Device and method for heating a liquid |
| JP4029092B2 (en) * | 2004-10-26 | 2008-01-09 | 日本ピラー工業株式会社 | Fluid heater and fluid heating device |
| FR2891720B1 (en) * | 2005-10-06 | 2007-12-14 | Seb Sa | LIQUID HEATING DEVICE FOR AN ELECTRICAL APPLIANCE. |
| US7477836B2 (en) * | 2006-11-02 | 2009-01-13 | Dolphin Industries, Inc. | Tankless water heater |
| US7567750B2 (en) * | 2007-08-16 | 2009-07-28 | Phile Yang | Instantaneous water heater with a heating tube |
| US8396356B2 (en) * | 2009-07-24 | 2013-03-12 | Balboa Water Group, Inc. | Bathing installation heater assembly |
-
2009
- 2009-11-09 DE DE202009015187U patent/DE202009015187U1/en not_active Expired - Lifetime
- 2009-11-11 US US13/128,285 patent/US20110217027A1/en not_active Abandoned
- 2009-11-11 JP JP2011543873A patent/JP2012515891A/en not_active Withdrawn
- 2009-11-11 RU RU2011123882/06A patent/RU2011123882A/en not_active Application Discontinuation
- 2009-11-11 EP EP09756061A patent/EP2359071A2/en not_active Withdrawn
- 2009-11-11 KR KR1020117013265A patent/KR20110095886A/en not_active Application Discontinuation
- 2009-11-11 CN CN2009801455266A patent/CN102317703A/en active Pending
- 2009-11-11 WO PCT/IB2009/055013 patent/WO2010055472A2/en active Application Filing
- 2009-11-13 CN CN2009202693926U patent/CN201569131U/en not_active Expired - Fee Related
Non-Patent Citations (1)
| Title |
|---|
| See references of WO2010055472A2 * |
Also Published As
| Publication number | Publication date |
|---|---|
| US20110217027A1 (en) | 2011-09-08 |
| CN201569131U (en) | 2010-09-01 |
| JP2012515891A (en) | 2012-07-12 |
| KR20110095886A (en) | 2011-08-25 |
| CN102317703A (en) | 2012-01-11 |
| DE202009015187U1 (en) | 2010-06-24 |
| WO2010055472A3 (en) | 2013-01-10 |
| WO2010055472A2 (en) | 2010-05-20 |
| RU2011123882A (en) | 2012-12-20 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US20110217027A1 (en) | Insert for a flow through heater | |
| JPH11347115A (en) | Cassette for distributing fluid, especially dialytic solution | |
| WO2007103131A3 (en) | Improved induction heater | |
| KR102447439B1 (en) | hot water creation module for water treatment apparatus | |
| WO2014205771A1 (en) | Thick film heating device | |
| US20110265354A1 (en) | Boiler having a section for preheating water | |
| GB2575942A (en) | Isolation valves and water systems | |
| JP2007315647A (en) | Fluid heater and control device of fluid heater | |
| GB0722350D0 (en) | Apparatus, system and method | |
| CN209006833U (en) | A kind of lower heating system and series welding device | |
| WO2018074165A1 (en) | Warming device and infusion system | |
| CN116717907A (en) | Continuous flow type water heating assembly and production method | |
| JP6097561B2 (en) | Food heat treatment apparatus and food heat treatment method | |
| KR101592536B1 (en) | Fluid circulation type heating apparatus | |
| CN113038857B (en) | Two-stage boiler for hot beverage vending machine | |
| RU2788353C2 (en) | Two-stage water-heating boiler for vending machine for hot drinks | |
| CN218495361U (en) | Water supply system | |
| KR101952890B1 (en) | Boiler that can control hot water temperature smoothly | |
| US10986956B2 (en) | Method and machine for preparing beverages | |
| EP3364836B1 (en) | Method and heat exchanger for preparing beverages | |
| JP2011163481A (en) | Thermosensitive pressure regulator | |
| JP2003202158A (en) | System for heating or warming liquid or fluid material instantly or in very short time period by electromagnetic induction heating system | |
| JP2024027605A (en) | label attachment device | |
| KR20120035899A (en) | Apparatus for circulating hot water | |
| KR20140011896A (en) | A induction heating hot water boilers using waste heat from heating equipment |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PUAI | Public reference made under article 153(3) epc to a published international application that has entered the european phase |
Free format text: ORIGINAL CODE: 0009012 |
|
| AK | Designated contracting states |
Kind code of ref document: A2 Designated state(s): AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO SE SI SK SM TR |
|
| AX | Request for extension of the european patent |
Extension state: AL BA RS |
|
| DAX | Request for extension of the european patent (deleted) | ||
| STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: THE APPLICATION HAS BEEN WITHDRAWN |
|
| R17D | Deferred search report published (corrected) |
Effective date: 20130110 |
|
| 18W | Application withdrawn |
Effective date: 20130201 |