Insulating body for a heating block

Abstract

Insulating body (10) for a heating block (1), in particular of an instantaneous water heater, with a flow channel (12) for guiding liquid, wherein the flow channel (12) has a measuring section (16) with an opening (17) which extends from the outside into the flow channel (12) and which is designed such that a fluid flow sensor (60) can be arranged in the flow channel (12), wherein the flow channel (12) has a nozzle section (14) located in the flow direction upstream of the measuring section (16), which reduces a cross-section of the flow channel (12), wherein the insulating body (10) with flow channel (12), measuring section (16) and nozzle section (14) is formed in one piece and is manufactured in particular by means of an injection molding process.

Description

[0001] The invention relates to an insulating body for a heating block, in particular of an instantaneous water heater, a heating block, in particular for an instantaneous water heater, as well as an instantaneous water heater and a method for manufacturing an insulating body of an instantaneous water heater.

[0002] The use of a flow sensor to measure water flow, particularly in instantaneous water heaters, is well-known. The flow rate is important for purposes such as controlling the heating elements of the instantaneous water heater to provide a desired heating output, limiting the fluid flow through the heater, or statistically evaluating water consumption.

[0003] Typically, the flow sensor is housed in a separate casing that must be connected to an insulating element of the heating block. For example, the casing is screwed to one end of the heating block. A disadvantage is that the additional casing hinders a compact design of the instantaneous water heater, as it requires extra space. Furthermore, the additional component results in additional manufacturing costs.

[0004] A heating block for hot water appliances, which has an integrated opening for a volume flow sensor in its insulating body, is disclosed, for example, in DE 10 2007 060 190 A1. An axle is inserted coaxially with the opening, which is rigidly connected to a rotary closure that seals the opening and which has a vane on its lower section that rotates freely around the inserted axle in the flow channel of the heating block.

[0005] This well-known integration of the fluid flow sensor into the flow path of the heating block results in a manufacturing-complex widening of the flow channel perpendicular to the axis of the opening and additionally leads to an unfavorable position of the impeller in the flow path, which hinders precise measurement of the flow rate. Furthermore, with such an impeller arrangement, a complex calibration is required, along with the use of a sophisticated algorithm for data evaluation.

[0006] The present invention was therefore based on the objective of improving a known insulating body for a heating block in such a way that the quantity of a fluid flowing through the insulating body can be measured more accurately and easily without complicating the design.

[0007] According to the invention, the problem is solved by an insulating body for a heating block with a flow channel for guiding liquid. The flow channel has a measuring section with an opening that extends into the flow channel from the outside and is configured such that a fluid flow sensor can be arranged in the flow channel. The flow channel has a nozzle section located upstream of the measuring section in the flow direction, which narrows the cross-section of the flow channel. The insulating body with flow channel, measuring section, and nozzle section is formed in one piece. Preferably, the insulating body is manufactured by injection molding. Preferably, the heating block is a heating block of an instantaneous water heater.

[0008] The measuring section of the flow channel is preferably the area where the inner wall of the flow channel deviates from a cylindrical or conical shape, for example, corresponding to the area designed to accommodate the fluid flow sensor. The fluid flow sensor preferably has an impeller that rotates at different speeds depending on the flow velocity through the flow channel.

[0009] The nozzle section of the flow channel increases the fluid flow velocity. In particular, turbulent flow can occur through the measuring section. Thanks to the increased flow velocity, the behavior of the fluid flow sensor, especially the impeller, can be linearized over a wide volume flow range. This advantageously reduces calibration effort and simplifies the algorithm for evaluating the volume flow by the electronics or software of the instantaneous water heater. Integrating the nozzle section into the flow channel of the insulating body also allows for a compact device design and saves manufacturing costs. This is further enhanced by the fact that the measuring section, including the opening, is also located within the insulating body.By arranging the nozzle section, measuring section and opening in a single component, tolerances are minimized, which increases the accuracy of the fluid flow measurement.

[0010] Finally, the insulating body according to the invention makes it possible to reduce the number of individual parts and interfaces, since no additional components, for example for the nozzle section, are required.

[0011] The insulating body is preferably made of plastic material. In the preferred injection molding process, the nozzle section in the plastic insulating body is produced directly by two mold cores that axially form the contour for the nozzle section. The production of the insulating body according to the invention is therefore possible with minimal effort.

[0012] In one embodiment, the nozzle section has a conical section adjacent to the measuring section. The conical section, through its simple shape, ensures a defined taper and a defined nozzle effect of the nozzle section, that is, a defined effect of increasing the flow velocity.

[0013] In one embodiment, the cross-sectional area of ​​the flow channel is smaller at the beginning of the measuring section than at the end. The flow velocity through the channel is therefore higher at the inlet than at the outlet. This simplifies a more accurate measurement of the volumetric flow rate through the measuring section.

[0014] In one embodiment, the flow channel has several parallel flow channel sections. The nozzle section and the measuring section are thus formed within one of these parallel flow channel sections. Multiple parallel flow channel sections lengthen the flow path through the insulating body without increasing the dimensions of the device, such as the instantaneous water heater. This allows for a compact device design. The parallel flow channel sections can be formed, for example, by injection molding, using mold cores guided along parallel axes. A long flow path is desirable, for instance, to ensure sufficient insulation between the heating elements and the water outlet of the instantaneous water heater.

[0015] In one embodiment, the flow channel has at least one heating section. When the insulating body is used, for example in the instantaneous water heater, a heating element is installed in this at least one heating section. The heating element can, for example, be a bare wire heating element.

[0016] In one embodiment, the at least one heating section is arranged parallel to the nozzle section and the measuring section. For example, the heating section and the nozzle section, or the measuring section, are thus formed in different of the several parallel flow channel sections. This design enables a more compact device.

[0017] According to the invention, the problem is further solved by a heating block comprising an insulating body according to the invention and at least one heating element. The heating element is arranged in a heating section of the flow channel. In particular, the heating element is a bare heating wire element. Advantageously, the heating block thus integrates the function of heating the liquid in the flow channel as well as determining the fluid flow rate through the flow channel.

[0018] In one embodiment, the heating block further comprises a screen between the nozzle section of the flow channel and the opening. The screen enables a further optimized flow to the fluid flow sensor and thus allows for a further improvement in the evaluation of the volume flow passing through the flow channel.

[0019] The problem is further solved by an instantaneous water heater comprising a heating block according to the invention and a fluid flow sensor that closes the opening of the measuring section. The fluid flow sensor particularly includes a Hall sensor that measures a varying magnetic field generated by a magnet rotating within the flow channel through the flowing fluid. Preferably, the rotating magnet is attached to a rotating impeller.

[0020] The problem is further solved by a manufacturing process for an insulating body, wherein the insulating body is produced using an injection molding tool by means of an injection molding process, and wherein the nozzle section and the measuring section are formed directly by two tool cores of the injection molding tool during injection molding.

[0021] Manufacturing the insulating body, including the nozzle section and measuring section, directly using an injection mold in a single injection molding step simplifies production. Furthermore, manufacturing tolerances are minimized because the same injection mold can always be used, eliminating the need to match components.

[0022] Further advantages and embodiments are described below with reference to the accompanying figures. These show...

[0023] Fig. 1. Schematic and exemplary perspective view of a heating block according to the invention,

[0024] Fig. 2. A schematic and exemplary cross-section through the heating block in a first plane and

[0025] Fig. 3. A schematic and exemplary cross-section through the heating block in a second plane.

[0026] Fig. Figure 1 shows an example heating block in a perspective view. 1 , as it is used, for example, in an instantaneous water heater. The heating block 1 shows an entrance 2 , via the water, for example, from a pipe connection into the heating block 1 reached, as well as an outlet 4 up from the heating block 1 For example, heated water flows out for use. Through the heating block 1 A flow path runs through channels in insulating caps. 20 on both sides of an insulating body 10 as well as through flow channels 12 in the intermediate insulating body 10 runs within the insulating caps. 20 The liquid, for example water, is diverted and directed into one of the flow channels. 12 of the insulating body 10 guided.

[0027] In this example, water flows through the inlet. 2into the insulating cap shown on the left in the drawing 20 one and then, before they enter an inlet opening 11 into the first flow channel 12 of the insulating body 10 enters through a cooling section 6 , which is intended for cooling the (not shown) power electronics of the instantaneous water heater. After the inlet opening 11 The fluid passes a fluid flow sensor 60 , which passes through the flow channel 12 The flowing amount of liquid is measured. Before the liquid first enters the insulating cap. 20 is deflected, and flows in the opposite direction in a parallel flow channel 12 As it flows, it passes a flow restriction. 30 , which is designed, for example, in the form of a motor-adjustable valve and limits the fluid volume flow through the flow channel 12 made possible.

[0028] In some of the flow channels12 of the insulating body 10 between the insulating caps 20 Heating elements (not shown) are provided. These heating elements can, for example, be bare wire heating elements. After passing through the flow channel sections with heating elements, the water flows through a flow channel. 12 , in which a temperature sensor 50 and a safety temperature limiter 40 is installed. The temperature sensor 50 determines the temperature of the fluid flowing at this point and the safety temperature limiter. 40 Ensures that the water heater shuts off if a temperature exceeds a dangerous limit.

[0029] The fluid flow sensor 60 includes a bracket 64 , which is designed, for example, as a one-piece injection-molded part, and a recording 66for accommodating sensor electronics and mounting openings for accommodating fasteners 62 defined. The fasteners 62 In this example, the screws are those that hold the fluid flow sensor. 60 on the insulating body 10 attach.

[0030] The insulating body 10 In this example, it is a one-piece injection-molded part, for example made of a plastic material. The respective insulating caps 20 are attached to the insulating body 10 for example, fastened with screws. The cooling section 6 includes a copper pipe that is attached to the inlet opening 11 to the insulating body 10 is adapted. The safety temperature limiter. 40 and the temperature sensor 50 are attached to the insulating body by means of a common bracket 10 fastened, in particular screwed in.

[0031] The use of the fluid flow sensor 60in the insulating body 10 This will now be explained in more detail with reference to two cross-sections through the insulating body. 10 in Fig. 2 and Fig. 3 described. Fig. Figure 2 shows a cross-section along the insertion axis of the fluid flow sensor. 60 and Fig. Figure 3 shows a cross-section perpendicular to the insertion direction of the fluid flow sensor. 60 .

[0032] In Fig. 2 is the flow channel 12 of the insulating body 10 before and after the fluid flow sensor 60 shown. The flow channel 12 passes through a nozzle section 14 , in which a cross-section of the flow channel 12 The value is reduced from d1 to d2. After the nozzle section 14 The flow channel runs 12 through a measuring section 16 After the measuring section 16 the flow channel 12a cross-section d3 that is larger than the cross-section d2 at the beginning of the measuring section 16 is. The nozzle section 14 includes a conical section 18 , which is located on the inner edge of the flow channel 12 is formed, and ensures a narrowing of the cross-section. In the measuring section 16 the flow channel 12 an opening 17 on, which in Fig. 2. Example on the upper side of the flow channel 12 is shown. Through the opening 17 Part of the fluid flow sensor protrudes 60 into the fluid flow of the flow channel 12 inside. The bracket 64 of the fluid flow sensor 60 is by means of sealing elements 68 , for example an O-ring, against the insulating body 10 sealed so that no liquid can escape from the flow channel 12 about the opening 17 can escape.

[0033] The part of the fluid flow sensor 60 , which is in the flow channel 12 The arrangement includes a rotor. 70 , which revolves around an axis 72 rotates when liquid passes through the flow channel 12 flows. Together with the impeller 70 It rotates behind the impeller in the drawing. 70 lying magnet 74 around the axis 72 . Due to the rotation of the magnet 74 The generated, time-varying magnetic field is reflected in the recording. 66 The sensor to be placed is detected and the rotational speed of the magnet is determined. 74 , or rather the impeller 70 , inferred from the flowing volumetric flow rate. Hall sensors, for example, are used for this purpose. The axis 72 stands vertically on the insertion opening 17 , through which the fluid flow sensor 60 is introduced. Thus, the ones attached to the insulating body 10The necessary modifications for flow measurement are minimal. Furthermore, optimal measurement of the flowing liquid volume is achieved, especially compared to a paddle wheel. 70 , which rotates around an axis that corresponds to the insertion direction of the fluid flow sensor 60 If the arrangement shown corresponds to this, a more accurate and less error-prone measurement can be achieved.

[0034] Through the nozzle section 14 will change the behavior of the wheel 70 linearized over a large volume flow range, since the flow velocity through the flow channel 12 The flow rate is increased, resulting in turbulent flow. Linearization reduces the effort required to calibrate the fluid flow sensor. 60required, and the evaluation by the electronics or software is possible with a simpler algorithm. Also, since the nozzle is part of the insulating body 10 Once trained, no additional component is required.

[0035] Fig. Figure 3 shows a cross-section through the flow channel 12 and the fluid flow sensor 60 perpendicular to an insertion direction of the fluid flow sensor 60 . elements that are similar to those in Fig. The sections corresponding to 2 were labelled with the same reference numerals. It should be noted that although the cross-sections d1, d2, d3 in this case have the same designation as in Fig. 2. The cross-sections do not necessarily have to be round. Rather, the cross-sections at points d1, d2 and / or d3 can also have other shapes, such as oval or otherwise non-round shapes.

[0036] Fig. 3 shows the axis 72, perpendicular to the flow channel 12 and on the insertion direction of the fluid flow sensor 60 (perpendicular to the plane of the drawing). The wheel 70 is with the magnet 74 coupled so that they are concentric around the axis 72 proportional to the flow through the flow channel 12 rotate the flowing fluid. QUOTES INCLUDED IN THE DESCRIPTION

[0037] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0038] DE 102007060190 A1

[0004]

Claims

[1] Insulator ( 10 ) for a heating block ( 1 ), in particular an instantaneous water heater, with a flow channel ( 12 ) for guiding liquid, where the flow channel ( 12 ) a measuring section ( 16 ) with an opening ( 17 ) exhibits, which enter the flow channel from the outside ( 12 ) is sufficient and is set up in such a way that a fluid flow sensor ( 60 ) in the flow channel ( 12 ) can be ordered, where the flow channel ( 12 ) in the direction of flow in front of the measuring section ( 16 ) located a nozzle section ( 14 ) which has a cross-section of the flow channel ( 12 ) rejuvenates, where the insulating body ( 10 ) with flow channel ( 12 ), measuring section ( 16 ) and nozzle section ( 14 ) is formed in one piece and is manufactured in particular by means of an injection molding process. [2] Insulators ( 10 ) according to claim 1, wherein the nozzle section ( 14 ) one attached to the measuring section ( 16 ) adjacent conical section ( 18 ) exhibits. [3] Insulators ( 10 ) according to claim 1 or 2, wherein the cross-section of the flow channel ( 12 ) in the direction of flow at the beginning (d2) of the measuring section ( 14 ) smaller than at the end (d3) of the measurement section ( 14 ) is. [4] Insulators ( 10 ) according to one of the preceding claims, wherein the flow channel ( 12 ) has several parallel flow channel sections. [5] Insulators ( 10 ) according to one of the preceding claims, wherein the flow channel ( 12 ) has at least one heating section. [6] Insulators ( 10 ) according to claim 5, wherein the at least one heating section is parallel to the nozzle section ( 14 ) and the measuring section ( 16 ) is. [7] Heating block ( 1 ), which is an insulating body ( 10 ) according to one of the preceding claims and comprising at least one heating element, in particular a bare heating wire element, which is located in a heating section of the flow channel ( 12 ) is arranged. [8] Heating block ( 1 ), which further includes a sieve between the nozzle section ( 14 ) and opening ( 17 ) of the measuring section ( 16 ) exhibits. [9] Instantaneous water heater, which has a heating block ( 1 ) according to claim 7 or 8 and a fluid flow sensor ( 60 ) has the opening ( 17 ) of the measuring section ( 16 ) closes. [10] Manufacturing process for an insulating body ( 10 ) according to any one of claims 1 to 6, wherein the insulating body ( 10 ) is produced using an injection mold by means of an injection molding process, wherein the nozzle section ( 14) and the measuring section ( 16 ) are formed directly by two tool cores of the injection mold during injection molding.

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