Flow heater

Abstract

A flow heater includes: a housing having a base portion and a cover portion; a channel for the liquid to be heated, the channel extending from the inlet to the outlet; a heating plate adjacent to the channel; the fins are arranged in the channel and are in contact with the heating plate, and the printed circuit board is arranged between the inner wall of the shell and the cover part. The inner wall has at least one portion inclined relative to the heating plate. Between the heating plate and the inner wall, the channel has a first wedge-shaped portion downstream of the inlet and a second wedge-shaped portion leading to the outlet. The two wedge-shaped portions taper from one end of the heating plate adjacent the inlet and the outlet to the opposite end. The wedge portions are connected by an intermediate portion of the flow channel, and a flow direction in the intermediate portion intersects a flow direction in the wedge portions. The printed circuit board is inclined with respect to the heating plate and inclined with respect to the cover portion and disposed in a wedge-shaped space defined by the inner wall and the cover portion. The wedge-shaped space is tapered in a direction opposite to a direction in which the first and second wedge-shaped channel portions are tapered.

Description

Technical Field

[0001] The invention relates to a flow heater for heating a liquid. Background Art

[0002] A flow heater having the features listed in the preamble of claim 1 is disclosed in US 2022 / 0082297 A1.

[0003] For example, flow heaters are required in automobiles to heat various liquids (especially water and aqueous solutions). Constant goals in developing flow heaters for automobiles are compact design, low manufacturing costs and high efficiency. Summary of the invention

[0004] It is an object of the present invention to provide a flow heater which achieves these objects to a greater extent.

[0005] The flow heater according to the invention comprises a channel for a liquid to be heated, the channel being arranged between a heating plate and an inner wall, the inner wall having at least one portion inclined relative to the heating plate. Thus, the channel has a first wedge-shaped portion adjacent to the inlet and a second wedge-shaped portion adjacent to the outlet, the two wedge-shaped portions tapering from one end of the heating plate adjacent to the inlet and the outlet to the opposite end. The wedge-shaped portions are connected by a middle portion of the flow channel, the flow direction in the flow channel intersecting the flow direction in the wedge-shaped portions.

[0006] Along the length of the first wedge-shaped portion of the channel, the liquid to be heated enters the middle portion of the flow channel and flows in the middle portion in a direction intersecting the length of the first wedge-shaped portion. Therefore, only a small portion of the liquid to be heated reaches the end of the first wedge-shaped portion. The rest of the liquid enters the middle portion along the path. Similarly, when the liquid enters the second wedge-shaped portion along the path, the amount of liquid in the second wedge-shaped portion increases in the direction toward the outlet. This channel allows a large amount of liquid to be efficiently heated in a short time.

[0007] The compactness of the design achieved by the passage arranged as described above is further improved by arranging the printed circuit board obliquely relative to the heating plate in the wedge-shaped space defined by the inner wall portion and the cover of the housing. As a result, the length of the circuit board can be greater than the length of the housing. Furthermore, by arranging small flat components of the end portions of the circuit board in the end portions adjacent to the inlet and outlet, and arranging large components such as capacitors in the opposite end portions, the volume enclosed by the housing can be used very effectively, thereby forming a very compact flow heater. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] The above aspects of the exemplary embodiments will become more apparent and will be better understood by referring to the embodiments described below in conjunction with the accompanying drawings, in which:

[0009] Figure 1 A flow heater according to the invention is shown.

[0010] Figure 2 is a cross-sectional view of the flow heater along line AA.

[0011] Figure 3 is a cross-sectional view of the flow heater along line CC.

[0012] Figure 4 is a cross-sectional view of the flow heater along line BB, wherein arrows indicate the flow direction of the liquid;

[0013] Figure 5 is a cross-sectional view of another embodiment of a flow heater in addition to the appended claims; and

[0014] Figure 6 is a cross-sectional view of another embodiment of a flow heater in accordance with the appended claims. DETAILED DESCRIPTION

[0015] Figure 1 A flow heater is shown. Figure 2 In the cross-sectional view along line AA, Figure 3 In the cross-sectional view along line CC and Figure 4 The same flow heater is schematically shown in a cross-sectional view along line BB.

[0016] The flow heater comprises a housing having a base 1, a first cover 2 and a second cover 3. The housing may be in the shape of a rectangular parallelepiped as shown in the figure. The base 1 has two opposite short sides 1a, 1b and two opposite long sides 1c, 1d, and the two short sides 1a, 1b and the two long sides 1c, 1d are arranged between the two covers 2, 3.

[0017] The base 1 is provided with an inlet 4 and an outlet 5, for example on one short side 1a of the base 1. The liquid to be heated flows from the inlet 4 to the outlet 5 through a channel inside the housing. Figure 2 The cross-sectional view shows the end portion 6 of the channel adjacent to the outlet 5, and Figure 3 The cross-sectional view of shows another part 7 of the channel, which is downstream of the inlet 4. The parts 6 and 7 of the flow channel are arranged between and defined by the heating plate 8 and a part of the inner wall 9 of the housing. The inner wall 9 is part of the base 1 and may be integral with the base 1.

[0018] like Figure 2 As shown, a portion of the inner wall 9 is inclined relative to the heating plate 8. The end portion 6 of the channel is wedge-shaped. The channel portion 6 tapers away from the outlet 5, and the channel portion 7 tapers away from the inlet 4.

[0019] exist Figure 4 In FIG. 4 , arrows are used to schematically show the route of the channel. The liquid to be heated flows from the inlet 4 to the Figure 3 The flow through the wedge-shaped portion is formed in a similar structure to the end portion 6. Figure 4 The liquid flows from this wedge-shaped portion into a middle portion 14 of the channel which is bounded on one side by the heating plate 8 and on the opposite side by a portion 11 of the inner wall 9. The flow in this portion is Figure 3 It is shown by arrow 12. It should be noted that for space reasons, arrow 12 is shown outside the housing, but the middle part of the flow channel is of course inside the housing. The middle part 14 of the channel leads to Figure 2 The end portion 6 of the flow passage is shown and is Figure 4 This is indicated by arrow 13.

[0020] Figure 4 is limited to the details necessary to understand the route of the passage. Figure 2 The printed circuit board 16 and other details shown in FIG. Figure 3 Shown in.

[0021] The wedge-shaped portion 7 downstream of the inlet 4 is also referred to as the first wedge-shaped portion, and the wedge-shaped portion 6 leading to the outlet 5 is also referred to as the second wedge-shaped portion. The two wedge-shaped portions are connected by a middle portion 14, which may have a constant height measured perpendicularly to the heating plate 8. The flow direction in the wedge-shaped portion 6 is cross-sectional (e.g., perpendicular) to the flow direction in the middle portion 14. Fins 20 in contact with the heating plate 8 are arranged in the channel, particularly in the middle portion 14 of the channel.

[0022] The fins 20 may be corrugated metal sheets connected to the heating plate 8, for example by brazing. The heating plate 8 is provided with heating resistors, for example resistive tracks, arranged on a substrate. The substrate may be a metal plate covered by a dielectric layer, in which resistive tracks are arranged as heating resistors, in particular on the side of the substrate facing away from the fins 20.

[0023] like Figure 4 As shown, the inner wall 9 defining the heating channel can have a middle portion 11 parallel to the heating plate 8 and inclined portions on both sides of the middle portion 11. The middle portion 14 of the channel thus has a constant height, while the portions 6, 7 on both sides of the middle portion are wedge-shaped. These wedge-shaped portions 6, 7 of the flow channel taper towards the heating plate 8 and away from the ends of the inlet 4 and the outlet 5.

[0024] The two covers 2, 3 and the heating plate 8 are parallel to each other. Parallel here means that any deviation from a geometrically perfectly parallel orientation is within the manufacturing tolerance range.

[0025] like Figure 2 As shown, the inclined portion 9 of the inner wall and the first cover 2 of the housing define a wedge-shaped space 15, which tapers in a direction opposite to the direction in which the first and second wedge-shaped portions 6 of the channel taper. A printed circuit board 16 with control electronics is arranged inside this wedge-shaped space 15. The printed circuit board 16 is inclined relative to the heating plate 8 and also inclined relative to the covers 2, 3. As a result, a longer printed circuit board 16 can be arranged in the housing compared to if the printed circuit board 16 is oriented parallel to the heating plate 8 and the covers 2, 3. In addition, by the inclined arrangement of the printed circuit board 16 in the wedge-shaped space, the distance between the printed circuit board 16 and the first cover 2 gradually increases from one end of the printed circuit board 16 adjacent to the inlet 4 and the outlet 5 to the opposite end of the printed circuit board 16. Therefore, there is enough space at the end of the printed circuit board 16 for mounting large components such as capacitors 18 on the printed circuit board 16, while the other end can be used for smaller components of the control electronics.

[0026] The printed circuit board 16 and the heating plate 8 form an acute angle, which may be, for example, 3° to 10°. Figure 2 As shown, there may be a wedge-shaped gap 19 between the printed circuit board 16 and the inclined portion of the inner wall 9. The wedge-shaped gap 19 may taper in a direction opposite to the taper direction of the wedge-shaped space 15 in which the printed circuit board 16 is disposed. Thus, the gap 19 tapers toward the inlet 4 and the outlet 5.

[0027] exist Figure 5 and Figure 6 In, according to Figure 2 The cross-sectional view of FIG. 1 shows another embodiment of the flow heater. The same and corresponding parts of the flow heater of all embodiments are indicated by the same reference numerals in the various drawings. Figure 4 and Figure 5 The embodiment shown differs primarily in the interpretation of the printed circuit board 16. Figure 2 In the embodiment of the present invention, the printed circuit board 16 is tilted relative to the heating plate 8, and Figure 5 In the embodiment of the present invention, two separate, smaller circuit boards 16a, 16b are used, which are electrically connected by electrical conductors 21 such as wires. Figure 6 In the embodiment shown, a single printed circuit board 16 is used which is arranged parallel to the heating plate 8. Large components of the control electronics (e.g. capacitors) are arranged at the end of the printed circuit board 16 facing away from the inlet 4 and outlet 5 and on the surface of the printed circuit board 16 facing away from the first cover part 2.

[0028] Figure 5The illustrated embodiment relates to a flow heater, comprising: a housing, the housing comprising a base 1 and a cover 2; a channel for a liquid to be heated, the channel extending from an inlet 4 to an outlet 5; a heating plate 8 adjacent to the channel; a fin 20 arranged in the channel and in contact with the heating plate 8; and a printed circuit board 16 arranged between an inner wall 9 of the housing and the cover 2, wherein the inner wall 9 has at least one portion inclined relative to the heating plate 8. Between the heating plate 8 and the inner wall 9, the channel has a first wedge-shaped portion located downstream of the inlet and a second wedge-shaped portion 6 leading to the outlet 5, the two wedge-shaped portions gradually taper from one end of the heating plate 8 adjacent to the inlet 4 and the outlet 5 to the opposite end. The wedge-shaped portions are connected by a middle portion of the flow channel, and the flow direction in the middle portion intersects the flow direction in the wedge-shaped portion 6. And, the first printed circuit board 16a and the second printed circuit board 16b are arranged in a wedge-shaped space defined by the inner wall 9 and the cover 2, the wedge-shaped space gradually tapers in a direction opposite to the direction in which the first and second channel portions taper. The first printed circuit board 16 a and the second printed circuit board 16 b are disposed at different distances from the cover 2 .

[0029] Figure 6 The embodiment shown relates to a flow heater, comprising: a housing, the housing comprising a base 1 and a cover 2; a channel for a liquid to be heated, the channel extending from an inlet 4 to an outlet 5; a heating plate 8 adjacent to the channel; a fin 20 arranged in the channel and in contact with the heating plate 8; and a printed circuit board 16 arranged between an inner wall 9 of the housing and the cover 2, wherein the inner wall 9 has at least one portion inclined relative to the heating plate 8. Between the heating plate 8 and the inner wall 9, the channel has a first wedge-shaped portion located downstream of the inlet and a second wedge-shaped portion 6 leading to the outlet 5, the two wedge-shaped portions taper from one end of the heating plate 8 adjacent to the inlet 4 and the outlet 5 to the opposite end. The wedge-shaped portions are connected by a middle portion of the flow channel, and the flow direction in the middle portion intersects the flow direction in the wedge-shaped portion 6. And, the printed circuit board 16 is arranged in a wedge-shaped space defined by the inner wall 9 and the cover 2, the wedge-shaped space tapers in a direction opposite to the direction in which the first and second channel portions taper. The printed circuit board is disposed adjacent to the cover 2 , parallel to the cover 2 , and has components such as capacitors disposed on a surface facing away from the cover 2 .

[0030] Reference numerals list

[0031] 1 Base

[0032] 1a Short side

[0033] 1b Short side

[0034] 1c Long side

[0035] 1d Long side

[0036] 2 cover

[0037] 3 cover

[0038] 4 Entrance

[0039] 5. Exit

[0040] 6 Channel Section

[0041] 7 Channel Section

[0042] 8 Heating Plate

[0043] 9 Inner wall

[0044] 10 Arrow

[0045] 11 Inner wall

[0046] 12 Arrow

[0047] 13 Arrow

[0048] 14 The middle part of the channel

[0049] 15 Wedge Space

[0050] 16 Printed Circuit Board

[0051] 16a Printed Circuit Board

[0052] 16b Printed Circuit Board

[0053] 18 Capacitor

[0054] 19 Gap

[0055] 20 fins

Claims

1. Flow heater, comprising: The housing comprises a base (1) and a cover (2). a channel for the liquid to be heated, extending from the inlet (4) to the outlet (5), a heating plate (8) adjacent to the channel, a fin (20) disposed in the channel in contact with the heating plate (8), and A printed circuit board (16) is arranged between the inner wall (9) of the housing and the cover (2), Features: The inner wall (9) has at least one portion inclined relative to the heating plate (8); Between the heating plate (8) and the inner wall (9), the channel has a first wedge-shaped portion (7) located downstream of the inlet and a second wedge-shaped portion (6) leading to the outlet (5), the two wedge-shaped portions (6, 7) gradually becoming thinner from one end of the heating plate (8) adjacent to the inlet (4) and the outlet (5) to the opposite end; The wedge-shaped parts (6, 7) are connected via a middle part (14) of the flow channel, and the flow direction in the middle part (14) intersects with the flow direction in the wedge-shaped parts (6, 7); The printed circuit board (16) is tilted relative to the heating plate (8); and The printed circuit board (16) is inclined relative to the cover (2) and is arranged in a wedge-shaped space (15) defined by the inner wall (9) and the cover (2), and the wedge-shaped space (15) tapers in a direction opposite to the direction in which the first wedge-shaped channel portion (6) and the second wedge-shaped channel portion (7) taper.

2. The flow heater according to claim 1, wherein: The cover (2) and the heating plate (8) are parallel to each other.

3. A flow heater according to any one of the preceding claims, wherein: The capacitor (18) is arranged at an end portion of the printed circuit board (16) facing away from the inlet (4) and the outlet (5).

4. A flow heater according to any one of the preceding claims, wherein: The printed circuit board (16) and the heating plate (8) are arranged at an angle of 3° to 10° relative to each other.

5. A flow heater according to any one of the preceding claims, wherein: The gap (19) between the inner wall (9) and the printed circuit board (16) is wedge-shaped, and the gap (19) gradually becomes thinner toward the inlet (4) and the outlet (5).

6. A flow heater according to any one of the preceding claims, wherein: The fins (20) are oriented crosswise to the tapering direction of the wedge-shaped portion (6) of the channel.

7. A flow heater according to any one of the preceding claims, further comprising a second cover part (3) covering a surface of the heating plate (8) facing away from the channel.

8. The flow heater according to claim 7, wherein: The two cover parts (2, 3) are parallel to each other.

9. The flow heater according to claim 7 or 8, wherein: The base (1) has two opposite short sides (1a, 1b) and two opposite long sides (1c, 1d), and the two short sides (1a, 1b) and the two long sides are connected to the cover (2, 3).

10. The flow heater according to claim 9, wherein: The inlet (4) and the outlet (5) are both arranged on the same short side (1a) of the base (1).

11. A flow heater according to any one of the preceding claims, wherein: The shell is in a rectangular parallelepiped shape.

12. A flow heater according to any one of the preceding claims, wherein: The channel comprises a middle portion (14) having a constant height and connecting the wedge-shaped portions (6, 7).

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