This application claims priority to DE 10 2017 121 341.4, filed Sep. 14, 2017, the entire disclosure of which is hereby incorporated herein by reference.
This disclosure relates to a flow heater having an inlet and an outlet of the type generally described in DE 10 2013 105 270 A1.
In such a flow heater a plate-shaped heating insert defines a flow path in a housing by separating the interior of a housing into a part above and a part below the heating insert. Thus, heat is transferred to the liquid via both sides of the plate shaped heating insert.
Flow heaters are needed, e.g., in cars, for heating various liquids, especially water or water-based solutions. Common goals in developing flow heaters for cars involve a compact design, low manufacturing cost and a high efficiency such that a large amount of liquid can be heated in a short time.
This disclosure teaches a flow heater that meets the above goals to a larger extent.
In a flow heater according to this disclosure, the plate shaped heating insert comprises a first heating plate, a second heating plate, and a plate support arranged between the first heating plate and the second heating plate. Thus both heating plates can be exposed to the liquid to be heated so that an efficient heat transfer can be achieved. The first and the second heating plate are arranged on opposite sides of the plate support. The first and the second heating plate each comprise a substrate plate carrying a resistive layer. This enables a much more compact design than prior art flow heaters comprising PTC blocks arranged between two contact sheets.
The resistive layer may for example be a printed layer or a layer deposited by other means on a substrate, e.g., by vapor deposition. Resistive layers can be provided with a thickness of 0.2 mm or less. Hence, the plate shaped heating insert of this disclosure and the heating plates comprised therein can be very thin.
The substrate may be a ceramic plate, e.g., a plate of alumina or some other electrically insulating ceramic. The substrate may also be electrically conducting, e.g., the substrate may be a metallic sheet, like an aluminum sheet. If the substrate is an electrical conductor, an electrically insulating layer may be provided between the metal sheet and the resistive layer.
In a refinement of this disclosure, the plate support is a frame. A frame can be provided with very little mass so that the weight and thermal capacity of the heating insert is rather small. For example, the frame may have an outline that corresponds to the outline of the heating plates such that rim sections of the heating plates rest on the frame. The outline of the frame may surround an empty space or a space that is intersected by webs. In any case a frame can provide the heating insert with hollow spaces reducing its weight and thermal capacity.
The above-mentioned aspects of exemplary embodiments will become more apparent and will be better understood by reference to the following description of the embodiments taken in conjunction with the accompanying drawings, wherein:
The embodiments described below are not intended to be exhaustive or to limit the invention to the precise forms disclosed in the following detailed description. Rather, the embodiments are chosen and described so that others skilled in the art may appreciate and understand the principles and practices of this disclosure.
The flow heater shown in
The heating insert comprises a first heating plate 6, a second heating plate 7 and a plate support 8 arranged between the heating plates 6, 7. The heating plates 6, 7 may be fixed to the plate support 8, e.g., by means of an adhesive, welding or screwed fixations points, or be merely held in place by compression forces applied through the housing parts 3, 4.
The heating plates 6, 7 may be equal (the same or mirror images). An embodiment of heating plate 6 is shown in
The resistive layer 11 and the insulating layer 12 may be printed, e.g., as a paste or ink, or deposited by other means, e.g., vapor deposition. The resistive layer may be a PTC layer, e.g., based on barium titanate. The resistance layer 12 can be rather thin, e.g., 0.02 mm to 0.2 mm.
The heating plates 6, 7 are arranged such that their resistive layers 12 are facing each other. Thereby the resistive layer 12 is shielded by the substrate plate 10 from contact with liquid flowing along the flow path 5 through the flow heater.
The heating insert has an opening 14 (
The plate support 8 is a frame which also has a corresponding opening 15. The plate support may comprise gaskets (not shown) for sealing such that liquid passing through the opening 15 does not enter the dry space between the heating plates 6, 7.
The plate support 8 comprises a circumferential web 16 supporting the rim of the heating plates. The plate support 8 may comprise additional webs 17 for increased mechanical stability that traverse the interior space of the heating insert.
The flow heater may also comprise control electronics 18, e.g., arranged on a printed circuit board. Control electronics may be arranged on the dry side of housing part 4 and protected by a cover 19.
While exemplary embodiments have been disclosed hereinabove, the present invention is not limited to the disclosed embodiments. Instead, this application is intended to cover any variations, uses, or adaptations of this disclosure using its general principles. Further, this application is intended to cover such departures from the present disclosure as come within known or customary practice in the art to which this invention pertains and which fall within the limits of the appended claims.
Number | Date | Country | Kind |
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10 2017 121 341 | Sep 2017 | DE | national |
Number | Name | Date | Kind |
---|---|---|---|
1985830 | Hynes | Dec 1934 | A |
5438642 | Posen | Aug 1995 | A |
8346069 | Yeung | Jan 2013 | B2 |
20050047768 | Kuebler | Mar 2005 | A1 |
20130186966 | Taguchi | Jul 2013 | A1 |
20140348497 | Giffels et al. | Nov 2014 | A1 |
20150131979 | Kohl et al. | May 2015 | A1 |
20160069588 | Kominami et al. | Mar 2016 | A1 |
20160360574 | Bohlender et al. | Dec 2016 | A1 |
Number | Date | Country |
---|---|---|
104903658 | Sep 2015 | CN |
295 15 932 | Feb 1996 | DE |
197 20 880 | Nov 1998 | DE |
103 40 362 | Mar 2005 | DE |
10 2011 003 296 | Aug 2012 | DE |
10 2011 050 992 | Dec 2012 | DE |
10 2013 105 270 | Nov 2014 | DE |
2 689 945 | Jan 2014 | EP |
2 797 382 | Mar 2016 | EP |
2 734 007 | Sep 2016 | EP |
Entry |
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CN-104903658-A, Sep. 2015, Kwon, partial translation (Year: 2015). |
Number | Date | Country | |
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20190077224 A1 | Mar 2019 | US |