Electrofluid heater

Abstract

The invention relates to an electric fluid heater having a fluid-conducting housing in which at least one tube heating body, each having a plurality of spirals, is arranged. An inner region is defined by the helix, the inner region preferably extending along the helix axis. According to the invention, a displacement body assembly having at least one displacement body is arranged in the inner region, and a flow region for the fluid is formed on the outer circumference of the displacement body assembly. A spiral is also arranged in the flow region. The inner chamber assembly having at least one inner chamber of the displacement body assembly is largely or completely fluid-tightly separated from the flow region of the fluid. Transverse flow (i.e., transverse to the helical longitudinal axis) is avoided or completely avoided as much as possible.

Description

Technical Field

[0001] The invention relates to an electric heater for a fluid, in particular for a liquid, in particular for a cooling liquid. Background Art

[0002] Such an electric fluid heater is disclosed in WO 2011 / 054970 A2. Three tube heating bodies respectively form a plurality of spirals along a common spiral axis, wherein the spirals are arranged in a housing through which the fluid flows. The fluid thus flows around the spirals and is heated thereby.

[0003] An embodiment with a fluid guide is shown, in which a tube part is arranged in the housing inside the spiral along the spiral axis. The fluid to be heated first flows inside the tube part along the spiral axis, from there flows radially outwards through the through grooves on the outer circumference of the tube part and finally flows back on the outer circumference of the tube part. Since the spiral of the tube heating body is arranged on the outer circumference of the tube part, the first contact of the fluid with the spiral is also achieved there. External strips are arranged on the circumference of the tube part, which extend along the tube part and on which the tube heating body can be supported. The external strips can also take on the function of flow guidance.

[0004] Disadvantages of such electric fluid heaters are the transverse flow and the resulting limited power density. Summary of the invention

[0005] The object of the present invention is to increase the power density of such an electric fluid heater.

[0006] This object is achieved by an electric fluid heater having the features of claim 1. Further advantageous embodiments are the subject matter of the dependent claims.

[0007] The claimed electric fluid heater has a housing for guiding fluid, in which at least one tube heating body with multiple spirals is arranged. The inner area is defined by the spiral, and the inner area preferably extends along the spiral axis. According to the present invention, a displacement body assembly with at least one displacement body is arranged in the inner area, and a flow area for the fluid is formed on its periphery. A spiral is also arranged in the flow area. The inner cavity assembly with at least one inner cavity of the displacement body assembly is separated from the flow area of ​​the fluid to a large extent or completely fluid-tight. To a large extent, for example, separation means that 90%, preferably 95% of the inner cavity assembly is surrounded by a fluid-tight wall. Transverse flow (i.e., transverse to the longitudinal axis of the spiral) is avoided as much as possible or completely avoided. The working principle according to the present invention is to minimize the dead volume and reduce the flow cross section. This leads to an increase in the flow speed. Therefore, the power density of the fluid heater according to the present invention is increased, and therefore, it is possible to increase the heat transfer to the fluid and / or it is possible to reduce the structural space and / or the technical cost of the device. Therefore, in the variant of the present invention, the number of tube heating bodies known in the prior art is reduced.

[0008] It is simple in terms of production technology if the spiral produces a cylindrical shape, whereby the inner region also has a cylindrical shape.

[0009] In terms of device technology, the displacement body assembly is supported on the screw in a simple manner.

[0010] If the housing has two opposite housing end walls, which are preferably formed on a pot-shaped housing part, the displacement body arrangement extends over at least 90%, preferably at least 95%, of the distance between the two housing end walls in order to largely prevent transverse flows. The displacement body arrangement can also be supported on the two housing end walls.

[0011] In a first embodiment variant of the invention which is simple in terms of production technology, the (preferably exactly one) displacement body is a tube. The tube can be cylindrical, i.e. have a uniform cross section over its length, or it can have a diameter reduction (contraction). If more than two tube heating bodies are provided, more than one diameter reduction (contraction) can also be provided.

[0012] If the end sections of the tube are each at a distance from two mutually opposite housing end walls, two end covers are required to form a largely or completely fluid-tight wall according to the invention, which covers each face one of the two housing end walls. Alternatively, an internal partition wall can also be present in the tube. If more than two tube heating bodies are provided, more than one internal partition wall can also be provided.

[0013] In a second embodiment variant of the invention, two or more displacement bodies are provided, which can be easily manufactured in a substantially identical manner and in the case of two displacement bodies can be arranged, for example, mirror-symmetrically to one another.

[0014] In an exemplary embodiment of a second embodiment variant, the displacement bodies are corresponding cups which each have a bottom.

[0015] In the case of two cups, the two bottoms can face each other. The inner chamber component then has two separated inner chambers. Alternatively, each base plate can also be arranged adjacent to the corresponding housing end wall. The two cups can then be fastened to each other at their respective circumferential edges and / or inserted into each other. The two cups then together form a tubular displacement body component, wherein the inner chamber component in this case has exactly one inner chamber.

[0016] In a particularly preferred development, at least one displacement body (for example a tube or a cup) has a plurality of longitudinal ribs distributed over the jacket. In the case of a cylindrical tube or in the case of a cup, these longitudinal ribs can extend over the entire length of the displacement body, for example if they form a contact section with all turns of the tube heating body or if they form a flow element with a maximum length. Alternatively, the longitudinal ribs can also extend only over part of the length of the displacement body, for example if they form a contact section for only a few turns of the tube heating body.

[0017] It is also possible to provide exactly two longitudinal ribs lying opposite one another, which in a specific embodiment are shaped (homogenized) in such a way that an oval cross section of the tube results.

[0018] In order to also enable or improve the heat transfer from the inner side of the spiral to the fluid, it is important that inner flow sub-areas, which are designed, for example, as longitudinal grooves, remain between the longitudinal ribs, through which the fluid can flow between the spiral and the jacket of the corresponding displacement body and absorb heat. Such inner flow sub-areas also reduce undesired heat input into the interior.

[0019] According to a particularly preferred first basic principle of the present invention, the inner cavity of the displacement body component is a stagnant space into which the fluid penetrates. To this end, the displacement body component has at least one opening. The at least one opening can be a slot or a slit.

[0020] For example, during startup or after disassembly of the fluid heater, it is important that air can escape from the housing and, according to the first basic principle of the invention, also from the stagnant space for the fluid, ie that complete venting of the stagnant space also takes place via the at least one opening.

[0021] The elongated holes or slots can be introduced into the jacket of the displacement body (tube or cup) and / or extend approximately parallel to the screw axis.

[0022] In the case of a cup, at least one of the openings can also be arranged on the bottom of the cup. In the case of a tube, at least one of the openings can also be arranged on the end cover of the tube, so that the fluid can enter the stagnant space from the area between the end cover and the adjacent housing end wall and fill it. The openings can be formed by gaps arranged between triangular or circular arc sections of the cover.

[0023] According to the second basic principle of the invention, the displacement body assembly can also be formed by a fluid-tight tube, so that the inner cavity of the tube is separated from the fluid. Then the tube must be connected to the two housing end walls in a fluid-tight manner and at least one housing end wall has an opening, so that the inner cavity is connected to the ambient air. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 An electric fluid heater according to the invention is shown in a perspective view from below;

[0025] Figure 2 Shown in longitudinal section Figure 1 A fluid heater having a first variant of a displacement body assembly;

[0026] Figure 3 Shown in longitudinal section Figure 1 A fluid heater having a second variant of a displacement body assembly;

[0027] Figure 4 Shown in longitudinal section Figure 1 A fluid heater having a third variation of a displacement body assembly;

[0028] Figure 5 Shown in longitudinal section Figure 1 The electric fluid heater of claim 1, wherein the electric fluid heater has a first embodiment of a two-piece displacement body assembly;

[0029] Figure 6 Shown in cross section Figure 5 Fluid heater in;

[0030] Figure 7 Show Figure 5 and Figure 6 One of the two displacing bodies in ;

[0031] Figure 8 Shown to be used in Figure 1 Various embodiments of a one-piece displacement body assembly in a fluid heater;

[0032] Fig. 9 Shown to be used in Figure 1 Another embodiment of a one-piece displacement body assembly in a fluid heater;

[0033] Fig.10 Shown to be used in Figure 1 Another embodiment of a one-piece displacement body assembly in a fluid heater;

[0034] Fig.11 Shown to be used in Figure 1 Another embodiment of a one-piece displacement body assembly in a fluid heater;

[0035] Fig.12 Shown to be used in Figure 1 Another embodiment of a one-piece displacement body assembly in a fluid heater;

[0036] Fig.13 Shown to be used in Figure 1 Another embodiment of a one-piece displacement body assembly in a fluid heater; and

[0037] Fig.14 Shown to be used in Figure 1 Embodiment of a two-piece displacement body assembly in a fluid heater;

[0038] Fig.15 Shown to be used in Figure 1 Another embodiment of a two-piece displacement body assembly in a fluid heater; and

[0039] Fig.16 Shown to be used in Figure 1 Another embodiment of a two-piece displacement body assembly in a fluid heater. DETAILED DESCRIPTION

[0040] Figure 1 The electric fluid heater 100 according to the invention is shown in a perspective view from below. The fluid heater 100 has a housing in which a fluid chamber can be provided with reference to the following. Figures 2 to 16 Variants and exemplary embodiments of the displacement body arrangement according to the invention are described.

[0041] The housing consists of a pot-shaped housing part 6 and a substantially flat housing cover 10. To fluid-tightly close the fluid chamber defined in the pot-shaped housing part 6 and the housing cover 10, the two housing parts 6, 10 are materially connected to one another, for example welded or soldered.

[0042] On the bottom side of the pot-shaped housing part 6 (at Figure 1Two connections 8 for the fluid are formed at a distance from each other (in the middle and upper part), one of which is used as an inlet and the other as an outlet. In addition, two fastening tabs 6a are arranged on the pot-shaped housing part 6, by which the fluid heater 100 can be fastened in a vehicle whose coolant is to be heated, for example.

[0043] The housing cover 10 is on one side (on Figure 1 The protrusion is protruded from the pot-shaped housing part 6 (center right). The high-voltage connector 10a for supplying voltage to the fluid heater 100 is screwed onto the protrusion and the heavy bolt 10b is welded. In addition, the low-voltage connector 10c is screwed onto the protrusion, through which the LIN communication with the fluid heater 100 is realized.

[0044] An electronics housing 11 is arranged on the upper side of the housing cover 10 facing away from the fluid chamber in the operating position and is fastened sealingly to the housing cover 10 by means of a crimping web. The crimping web is formed uniformly on the edge of the electronics housing 11 and completely surrounds the edge of the housing cover 10. The electronics installation space is bounded by the housing cover 10 and the electronics housing 11. Electronics, power distribution rails and switching elements, such as IGBTs, are arranged in this electronics installation space (not visible).

[0045] With the help of Figures 2 to 16 General variants and specific embodiments of a displacement body assembly according to a first basic principle of the invention are described. The first basic principle is characterized in that at least one stagnant space 25 is formed in at least one inner cavity of the displacement body assembly, into which the fluid enters.

[0046] Figures 2 to 4 Shown separately Figure 1 The housing of the fluid heater 100 in the embodiment of the present invention. The respective spirals of the two tube heating bodies 2 extend along the spiral axis 4. The two end sections of the two tube heating bodies 2 with electrical connections extend in a sealed manner through the housing cover 10 to (at Figure 1 In the electronic device structure space of the electronic device housing 11 shown in Figures 2 to 4 In each case only the end section with the electrical connections is shown.

[0047] Figure 2 A first variant of a displacement body arrangement is shown. Figure 1The housing of the fluid heater 100 in the embodiment of the present invention. The displacement body assembly comprises a tube 101; 201; 301; 401; 501; 601 which is radially spaced from the spiral of the tube heating body 2 and which here rests on the end side preferably in a sealing manner against two housing end walls 12 of a preferably pot-shaped housing part 6. For this purpose, the tube 101; 201; 301; 401; 501; 601 is stretched or clamped between the two housing end walls 12. The initial filling of the stagnant space 25 thus provided is achieved by the radial openings 22 of the tube 101; 201; 301; 401; 501; 601. During the operation of the fluid heater 100, transverse flows are avoided to the greatest extent possible.

[0048] Figure 3 A second variant of the displacement body arrangement is shown. Figure 1 The housing of the fluid heater 100 in the embodiment of the present invention. The displacement body assembly comprises a tube 101; 201; 301; 401; 501; 601 which is radially stretched or clamped on a spiral of the tube heating body 2. The two end sides of the tube 101; 201; 301; 401; 501; 601 are spaced apart from the corresponding housing end wall 12 of the preferably pot-shaped housing part 6. The initial filling of the stagnant space 25 achieved in this way is achieved by two annular openings 23 in the region of the housing end wall 12. During the operation of the fluid heater 100, a small transverse flow is possible, more precisely along the two housing end walls 12 and from one annular opening 23 through the stagnant space 25 to the other annular opening 23.

[0049] In a sub-variant of the second variant, an end cover 26 is also provided on the tube 401; 501, or an internal separation wall is provided at any position along the spiral axis 4 in the tube 101; 201; 301; 601 (both are not provided in Figure 3 An opening is provided in the cover 26 or in the separating wall.

[0050] Figure 4 A third variant of the displacement body assembly is shown. Figure 1 The housing of the fluid heater 100 in the embodiment of the present invention. The displacement body assembly comprises two cups 1; 701; 801, which are radially stretched or clamped on the spiral of the corresponding tube heating body 2. The bottoms 16 of the two cups 1; 701; 801 are adjacent to each other and have a small distance between each other. The edges of the end sides of the two cups 1; 701; 801 are spaced apart from the corresponding housing end walls 12 of the preferably basin-shaped housing part 6. The initial filling of the two stagnant spaces 25 thus achieved is carried out respectively through the annular openings 23 formed between the edges of the cups 1; 701; 801 and the adjacent housing end walls 12. During operation of the fluid heater 100, a small lateral flow can be achieved directly along the two housing end walls 12 and between the bottoms 16 of the cups 1; 701; 801.

[0051] In the third variant (in Figure 4 In a sub-variant (not shown in FIG. 1 ), in order to minimize the lateral flow, the two cups 1; 701; 801 are against each other. Here, the two bottoms 16 are also or differently the two edges of the cups 1; 701 are against each other.

[0052] Specific embodiments of the present invention are described below based on the accompanying drawings.

[0053] Figure 5 An electric fluid heater 100 according to the invention is shown with a first embodiment of a displacement body assembly formed from two separate displacement bodies which are designed as respective cups 1 .

[0054] Two tube heating bodies 2 are provided, each with a plurality of turns, resulting in a cylindrical inner region which extends along the turn axis 4. Such an arrangement is known in principle from the prior art and therefore requires no further explanation.

[0055] The two cups 1 of the displacement element assembly are each inserted into a tube heating element 2. It is also possible to use two cups of different lengths, of which the longer cup is inserted into both tube heating elements 2.

[0056] according to Figure 5 The fluid heater of the embodiment of the present invention has a pot-shaped housing part 6, on the bottom side of which two connections 8 for a fluid, preferably a cooling liquid, are formed at a distance from one another along the screw axis 4. On the top side, the pot-shaped housing part 6 is sealed with a housing cover 10. The two end sections of the two tube heating bodies 2 with electrical connections extend outward in a sealed manner through the housing cover 10, wherein the two end sections of the two tube heating bodies 2 with electrical connections are sealed to the outside. Figure 5 Only the end section with the electrical connections is shown in each case.

[0057] Each cup 1 has a jacket and a bottom 16, wherein a rounded area is formed on the jacket adjacent to the bottom 16. The two cups 1 are designed identically and are inserted in the inner region of the spiral in a mirror-symmetrical manner so that the two bottoms 16 face each other and are at a small distance from each other. The two edges of the cups 1 each rest on the housing end wall 12 of the pot-shaped housing part 6. In particular, due to the distance between the two bottoms 16, the displacement body arrangement shown extends over at least 90%, preferably at least 95%, of the distance between the two housing end walls 12 along the spiral axis 4.

[0058] Figure 6 In the observation direction AA along the screw axis 4 (according to Figure 5 ) shows a cross section Figure 5A fluid heater in the tube. Here, a view of the bottom 16 of the cup 1 and of the flow areas 18, 20 for the fluid at the periphery of the cup 1 is obtained. It can be seen that the cup 1 has four longitudinal ribs 17 distributed on the circumference of its jacket, with which the cup 1 is held, for example, tensioned in the spiral of the tube heating body 2, and four longitudinal grooves are retained between the four longitudinal ribs 17. The longitudinal grooves each form an internal flow part area 18 for the fluid, through which the fluid can flow between the spiral and the jacket of the cup 1 and absorb heat. Undesirable heat input into the inner cavity of each cup 1 is also reduced by the internal flow part area 18. An external flow part area 20 is formed on the outer circumference of the spiral.

[0059] According to a first basic principle of the invention, the cup 1 has four openings formed as through-holes 22 , which are arranged in the region of the rounded corners of the jacket.

[0060] Figure 7 Show Figure 5 and Figure 6 One of the two cups 1 in the embodiment of the invention. Of the four through-holes 22 in the region of the rounded corners of the jacket, only one through-hole 22 can be seen. It is also shown that the jacket of the cup 1 has four longitudinal ribs 17, wherein an opening formed as a slot 24 is provided on one of the longitudinal ribs 17. A total of five openings allow the fluid to enter the interior of the cup 1 from the flow regions 18, 20, whereby 90%, preferably 95%, of the interior is separated from the flow regions 18, 20 by fluid-tight walls, whereby the fluid can enter the stagnant space 25 thus formed.

[0061] Figure 8 Different embodiments of a displacement body assembly are shown, which consists of a tube 101 which is provided for insertion into Figure 2 Or in the inner region of the spiral of the two tube heating body 2 in 3. The tube 101 has a cylindrical shape with five longitudinal ribs 17 distributed unevenly over the circumference and a corresponding number of inner flow part regions 18.

[0062] exist Figure 8 The longitudinal ribs 17 at the top are made in an overlapping manner so that a gap 17 can be produced there. In addition, the end edges of the tube 101 do not rest fluid-tightly on the two (at Figure 1 ) on the housing end wall 12, so that an opening is also produced there, whereby the interior cavity forms a stagnant space for the fluid.

[0063] Figure 8 The tube 101 can be constructed with a first variant (according to Figure 2 ) and the second variant (according to Figure 3 ) of the closed gap.

[0064] Fig. 9 Another embodiment of a one-piece displacement body assembly formed by a tube 201 is shown for insertion into Figure 2 and Figure 3 The tube in the heating element 2 is the inner region of the spiral. The tube 201 has a cylindrical shape with eight longitudinal ribs 17 distributed over the circumference and a corresponding number of inner flow section regions 18.

[0065] In two (in Fig. 9 An inner flow section area 18 is arranged between the longitudinal ribs 17 (which are located on the upper side) and is deeper than the other inner flow section areas 18.

[0066] Since the end edge of the tube 201 does not rest in a fluid-tight manner on the two ( Figure 1 ) on the housing end wall 12, so that an opening 23 is produced there, whereby the inner cavity forms a stagnant space 25 for the fluid. Thus, a second variant (according to Figure 3 ) tube 201.

[0067] Fig. 9 The tube 201 can also be inserted into the sheath after the opening is introduced in the first variant (according to Figure 2 )structure.

[0068] Fig.10 Another embodiment of a one-piece displacement body assembly formed of a tube 301 is shown for insertion into Figure 2 and Figure 3 The inner region of the spiral of the heating element 2 is similar to Fig. 9 In the exemplary embodiment of FIG. 3 , the tube 301 has a cylindrical shape with eight longitudinal ribs 17 evenly distributed over the circumference and a corresponding number of inner flow section areas 18 .

[0069] Since the end edge of the tube 301 does not rest in a fluid-tight manner on the two ( Figure 1 ) on the adjacent housing end wall 12, so that an opening is produced there, whereby the inner cavity forms a stagnant space 25 for the fluid. Thus, a second variant (according to Figure 3 ) tube 301.

[0070] Fig.10 The tube 301 can also be introduced into the sheath after the opening is introduced in the first variant (according to Figure 2 )structure.

[0071] Fig.11 Another embodiment of a one-piece displacement body assembly formed of a tube 401 is shown for insertion into Figure 2 and Figure 3The tube in the heating element 2 is the inner region of the spiral. The tube 401 corresponds to Figure 8 The tube 101 is different in that the tube has a cover 26 formed by a triangular or arc-shaped cover section at the end side. Due to the two covers 26, when the two end sides should be connected with the corresponding (at Figure 1 Even when the housing end wall 12 (shown in FIG. 1 ) has a significant distance, the interior space used as stagnation space is as closed as possible according to the invention.

[0072] Fluid can enter from the region between the end cover 26 of the tube 401 and the adjacent housing end wall 12 into the dead space and fill it, since the cover 26 has slots 24. These are arranged between the triangular or circular arc-shaped sections of the cover 26.

[0073] Fig.11 The tube 401 can be (according to Figure 3 The above-mentioned sub-variant scheme of the second variant scheme is constructed.

[0074] Fig.12 Another embodiment of a displacement body assembly is shown formed of a largely cylindrical tube 501 for insertion into Figure 2 and Figure 3 501 . The inner region of the spiral of the tube heater 2 in the embodiment of FIG. 501 . On the outer circumference, a group of four longitudinal ribs 17 distributed on the circumference are provided for each of the two tube heaters 2, which do not extend over the entire length of the tube 501 and serve as stop sections. The cross section of the inner flow section region 18 is thus maximized.

[0075] The tube 501 has a cap 26 at each end. Figure 1 Even when the housing end wall 12 (shown in FIG. 1 ) has a significant distance, a large degree of sealing of the interior space serving as stagnation space according to the invention is produced.

[0076] The fluid enters the interior of the tube 501 via corresponding openings in the cover 26 , which are designed as through-holes 22 , and via corresponding slots 24 provided on both sides of the longitudinal ribs 17 .

[0077] Fig.12 The tube 501 can be (according to Figure 3 The above-mentioned sub-variant scheme of the second variant scheme is constructed.

[0078] Fig.13 Another embodiment of a one-piece displacement body assembly formed of a tube 601 is shown for insertion into Figure 2 and Figure 3 The inner region of the spiral of the heating element 2 is heated by the tube. Fig.10The tube 301 in FIG. 6 has eight longitudinal ribs 17 evenly distributed on the circumference and a corresponding number of inner flow section areas 18. Differently, the tube 601 is not continuously cylindrical, but is provided with a constriction 28 in the middle, thereby Figure 2 and Figure 3 A corresponding cup-shaped section of the tube 601 is inserted into each tube heating body of the tube heating body 2 (shown in FIG. 1 ).

[0079] Fig.13 The tube 601 can be (according to Figure 3 A second variant of the invention and the introduction of an opening in the sheath is also carried out (according to Figure 2 ) A first variant is constructed.

[0080] for Figures 8 to 10 and Fig.13 The embodiment shown in the figure can provide an internal separation wall (not shown) in the tube 101; 201; 301; 601. In particular, when the end edge at the end of the tube 101; 201; 301; 601 does not abut against the housing end wall 12, a transverse flow can be prevented.

[0081] Fig.14 Shown to be used in Figure 1 Another embodiment of a two-piece displacement body assembly in the fluid heater 100 of FIG. Figure 7 The bottoms 16 of the cups 1 are in contact with each other.

[0082] Fig.14 The displacement body assembly with two cups 1 is shown in reference Figure 4 A sub-variant of the third variant mentioned is constructed.

[0083] Fig.15 An embodiment of a displacement body assembly is shown formed of two cups 701 for insertion into Figure 4 The two cups 701 are inserted into each other at their respective circumferential edges. Thus, the two cups 701 together form a tubular displacement body assembly with just one inner cavity.

[0084] The bottom 16 is arranged to be aligned with the corresponding Figure 4 The housing end wall 12 (shown in FIG) is adjacent.

[0085] Each cup 701 has four longitudinal ribs 17 evenly distributed over the circumference and a corresponding number of inner flow section areas 18 .

[0086] The fluid enters the interior of the tubular displacement body component via openings in the two bases 16 , each designed as a through-hole 22 , and via a plurality of slots 24 arranged between the longitudinal ribs 17 (in the flow section region 18 ).

[0087] At least one slit 24 is provided in the jacket of the cup 701, spaced from the edge of the cup, and at least one slit 24 extends to the respective edge of the cup 701, whereby two slits 24 formed on different cups 701 enable a longer slit of the displacement body assembly to be obtained.

[0088] Fig.15 The displacement body assembly with two cups 701 is shown in reference Figure 4 A sub-variant of the third variant mentioned is constructed.

[0089] Fig.16 Shown for Figure 1 Another embodiment of a two-piece displacement body assembly for use in the fluid heater 100 of FIG. 1 has two cup portions 801 for inserting Figure 4 The inner region of the spiral of the tube heating body 2. The two cups 801 are designed identically and are inserted into the inner region of the corresponding spiral in a mirror-symmetrical manner.

[0090] The two cups 801 abut against each other at their respective circumferential edges, so that the two cups 801 together form a tubular displacement body component with just one inner cavity.

[0091] The bottom 16 is arranged to be aligned with the corresponding Figure 4 The housing end walls 12 (shown in FIG) are adjacent and spaced apart.

[0092] Each cup 801 has a plurality of longitudinal ribs 17 evenly distributed over the circumference and a corresponding number of inner flow section areas 18 .

[0093] The ingress of the fluid into the interior of the tubular displacement body component is achieved via corresponding openings in the two bottoms 16 , which are designed as through-holes 22 .

[0094] Fig.16 The displacement body assembly with two cups 801 is shown in reference Figure 4 A sub-variant of the third variant mentioned is constructed.

[0095] and Figures 1 to 6 Unlike the fluid heater 100 shown in the drawing with two tube heating bodies 2, a housing extended along the spiral axis 4 can of course also be provided, wherein a spiral with three tube heating bodies 2 is arranged similarly to the prior art according to WO 2011 / 054970 A2. Thus, the performance compression according to the invention will be specifically manifested as a performance increase compared to WO 2011 / 054970 A2.

[0096] It is of course also possible to provide a housing which is elongated along the spiral axis 4 and in which four or more spirals of tube heating bodies 2 are arranged.

[0097] It is also possible to connect a plurality of the fluid heaters 100 shown and / or mentioned with their corresponding interfaces 8 in succession to one another in order to multiply the performance of a fluid heater assembly designed in this way.

[0098] Reference numerals list

[0099] 1;701;801 cups

[0100] 2-tube heating element

[0101] 4 Helical axis

[0102] 6 Basin-shaped housing part

[0103] 6a Fastening tab

[0104] 8 Connectors

[0105] 10 Housing cover

[0106] 10a high voltage connector

[0107] 10b Heavy Bolts

[0108] 10c low voltage connector

[0109] 11 Electronic device housing

[0110] 12 Shell end wall

[0111] 16 Bottom

[0112] 17 Longitudinal ribs

[0113] 18 Internal flow area

[0114] 20 External flow area

[0115] 22 Through Holes

[0116] 23 Annular opening

[0117] 24 Gap

[0118] 25 Stagnant Space

[0119] 26 Cover

[0120] 28 Contraction

[0121] 100 Electric fluid heater

[0122] 101; 201; 301; 401; 501 cylindrical tube

[0123] 601 pipe

Claims

1. An electric fluid heater having a housing for conducting a fluid, in which a plurality of spirals of at least one tube heating element (2) are arranged, wherein: An inner area is defined by the spiral, and is characterized in that a displacement body assembly having at least one displacement body (1; 101; 201; 301; 401; 501; 601; 701; 801) is arranged in the inner area, wherein a flow area (18, 20) for the fluid is formed on the outer circumference of the displacement body assembly, and the spiral is arranged in the flow area.

2. The electric fluid heater according to claim 1, wherein: The displacement body assembly is supported on the screw.

3. An electric fluid heater according to any one of the preceding claims, wherein The housing has two mutually opposite housing end walls (12) which are preferably formed on a pot-shaped housing part (6) which is preferably closed by a housing cover (10).

4. The electric fluid heater according to claim 3, wherein: The displacement body arrangement extends over at least 90%, preferably at least 95%, of the distance between the two housing end walls (12).

5. The electric fluid heater according to claim 3 or 4, wherein: The displacement body assembly is supported on the two housing end walls (12).

6. An electric fluid heater according to any one of the preceding claims, wherein The displacement body is a tube (101; 201; 301; 401; 501; 601).

7. The electric fluid heater according to claim 6, wherein: The tube (601) has at least one reduced diameter portion or constriction.

8. The electric fluid heater according to claim 6, wherein: The tube (101; 201; 301; 401; 501) is cylindrical.

9. An electric fluid heater according to any one of claims 3 to 5 and any one of claims 6 to 8, wherein The tube (401) has one or two end covers (26), which are respectively facing one of the two housing end walls (12), or the tube (101; 201; 301; 601) has at least one inner separating wall.

10. The electric fluid heater according to any one of claims 1 to 5, wherein: The displacement body assembly has two or more displacement bodies.

11. The electric fluid heater according to claim 10, wherein: The displacement bodies are cups (1; 701; 801) each having a bottom (16).

12. An electric fluid heater according to any preceding claim, wherein The at least one displacement body has a plurality of longitudinal ribs (17) distributed over the circumference or the jacket.

13. An electric fluid heater according to any preceding claim, wherein The at least one displacement body has at least one opening (22, 24) through which a fluid can enter a stagnant space (25) for the fluid and fill the stagnant space, which is formed in the displacement body component or in the displacement body.

14. The electric fluid heater according to claim 13, wherein: At least one of the openings is an elongated hole or slot (24) which is arranged approximately parallel to the screw axis (4) and / or is introduced into the jacket of the displacement body.

15. An electric fluid heater according to claim 9 and claim 13 or 14, wherein: At least one of the openings (22, 24) is arranged on a cover at the end of the tube (401; 501) or in the at least one inner separating wall.

16. An electric fluid heater according to any one of claims 12 and 13 to 15, wherein At least one of the openings (22) is arranged on the bottom (16) of the cup (701; 801).

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