DE102014001415B4 - Adjustment device for the passage of a fluid - Google Patents

Abstract

The invention relates to an adjusting device 1 for the passage of a fluid, in particular a hydrocarbon-containing fluid, in particular injection nozzle, hydraulic valve or pneumatic valve, with an inductive heating device 2, which comprises a current-carrying coil 3 and at least partially disposed within the coil 3 heating element, which by means of the coil 3 is inductively heated and is thermally coupled to the transfer of heat to the guided within the actuator 1 fluid flow, wherein the coil 3 comprises at least a plurality of turns comprehensive first coil section 8 and at least one further several turns comprehensive second coil section 9, wherein the first coil section. 8 forms at least one disposed within the second coil portion 9 position, wherein the coil 3 forming helically arranged electrical conductors in a arranged between the first and the second coil section 8, 9 Um Steering region 7 is formed such that the helical line formed by the first coil section 8 has the same winding direction as the winding direction of the helical line formed by the second coil section 9.

Description

The heating device comprises a current-carrying coil and a heating element arranged at least in sections within the coil, which heating element can be heated inductively by means of the coil. To transfer heat, the heating element is thermally coupled to a guided within the actuator fluid flow. The coil has at least one first coil section and at least one further second coil section, wherein each of the at least two coil sections comprises a plurality of turns. The first coil section forms an inner layer arranged within the second coil section. Accordingly, the coil of the heater is formed at least two layers.

Such components are typically designed as electromagnetic actuating devices, which comprise a magnet armature arranged in the interior, which is movable via a magnetic field generated by a further coil. In particular in the area of the injection nozzles or valves, such adjusting devices are used for controlling a supply of a hydrocarbon-containing fuel in an internal combustion engine.

It has proven problematic here that the temperature of the fuel has a significant influence on the atomization and the mixing with oxygen. This has a significant influence on the pollutant emission of the internal combustion engine, which is negatively influenced depending on the fuel used, especially during a cold start.

To solve this problem has been proposed, especially in the front region of the injection nozzle, d. H. in the region of the injection nozzle, which points in the direction of the combustion chamber of the internal combustion engine, to provide a heating device. Such heaters typically have coils which are designed, for example, as resistance heaters. However, heating devices are also known which are designed as induction heaters and thus heat a heating element arranged inside the coil by means of electromagnetic induction.

The problem with such devices, in particular in the field of motor vehicle construction is that only a very limited space is available to ensure a sufficiently strong field generating coil winding, so that a sufficient inductive heating of the heating element is made possible.

The printed prior art will continue to the documents DE 10 2011 085 680 A1 . DE 10 2007 050 550 A1 . DE 41 05 999 A1 . DE 11 62 482 A . DE 601 05 080 T2 and DE 196 02 614 A1 directed.

Based on this prior art, it is an object of the present invention to provide a control device with heating device, which has a particularly compact design.

This object is achieved by an adjusting device according to claim 1 and the use of the adjusting device in an internal combustion engine according to claim 19. With regard to a method for producing the adjusting device, the object is achieved by a method according to claim 21.

Advantageous embodiments of the invention are the subject of the dependent claims.

As the gist of the invention, it is considered that a coil-shaped helical conductor is deflected in a deflection region disposed between the first and second coil portions such that the helix formed by the first coil portion has the same winding direction as the winding direction of the second coil portion formed helix. In the context of the present invention, the winding direction is defined by the so-called "right hand rule". Accordingly, a helix or helix is right-handed when it winds along an axial direction in a clockwise direction. If the helix winds counterclockwise along the axial direction, it will be left-handed.

The coil according to the invention thus has at least two layers, wherein the winding direction of each of the two layers is either left-handed or right-handed. As a result, the layer arranged inside the second coil section, which is referred to as the first coil section, is arranged such that the helical conductor of the first coil section is arranged in the region of the recesses formed between the individual turns of the second coil section , As a result, a particularly compact coil is formed in which in particular space is saved in the radial direction.

Such a coil can be made particularly inexpensive from round wire. In particular, materials such as copper and copper-containing alloys are suitable for producing the coil.

According to the invention, provision is made for the production of the adjusting device comprising the coil, in that the first coil section forming the inner layer of the coil is formed by winding the electrical conductor over an expansion core in one direction of rotation with simultaneous displacement in the axial direction. The conductor is deflected in the deflection region and then the outer layer, which consists of the second coil section, formed by that the conductor is wound against the original direction of rotation with simultaneous displacement against the original axial direction. According to the "right-hand rule", it follows that the helices formed by the first and the second coil section has the same winding direction. In particular, the winding direction of the two coil sections is right-handed when, with simultaneous displacement in the axial direction, the direction of rotation is in the clockwise direction. Otherwise, the winding direction of the two coil sections is left-handed.

It is understood that the pitch of the coil in the first and in the second coil section is preferably the same. This allows the first coil section to be disposed within the second coil section over its entire axial length such that the turns of the first coil section are each arranged between the turns of the second coil section. Overlaps or "Überseilungen" are completely avoided with such an arrangement. The space available in particular in the radial direction space is used optimally.

In a further development of the invention, it has proved to be advantageous to interconnect the first and the second coil section parallel to one another. This results in a minimization of the electrical resistance of the coil thus formed, maintaining the design-related high fill factor. It is thus possible to provide relatively large currents for generating the field causing the inductive heating of the heating element. As a result, such an embodiment of the invention allows a compact design, which ensures a particularly good inductive heating of the heating element.

In a particularly advantageous embodiment of the invention, a contact element is provided for parallel connection of the two coil sections, which contacts the coil in the deflection region in an electrically conductive manner. The deflection region, which is naturally arranged at the end of the coil, thus additionally functions as a connection region for the electrical connection of the two coil sections.

The contact element may be formed rail-shaped in a first embodiment and preferably has a flat shape in order to save space.

Alternatively, it is possible, starting from the deflection region to form a wire loop, which is formed by the angle wire of the two coil sections and passes into this. This wire loop is then returned parallel to the coil axis to a connection region of the device and thus forms a formed of two linear winding wire sections feedback element.

In a further development of the invention, it is provided to receive the rail-shaped contact element or the wire loop in a longitudinal recess of a shielding housing, which is designed substantially cylindrical and surrounds the coil. The shield case serves as a magnetic shield to the outside and thus forms an outer iron circle. The inclusion of the rail-shaped contact element within the longitudinal receptacle causes the contact element no further space in the radial direction is claimed. In addition, the longitudinal recess in the shielding housing advantageously prevents magnetic field generating eddy currents.

As a particularly simple, yet robust way to produce the electrically conductive connection between the contact element and coil, it has been found to connect the rail-shaped contact element by means of a resistance welding to the coil.

Outside the deflection region, the contact element is electrically insulated from the coil in sections by means of a plastic sheath. The plastic covering preferably comprises a heat-resistant thermoplastic, in particular a polyphenylsulfide, in order to ensure adequate thermo-mechanical robustness in the intended use of the adjusting device. In particular, in terms of manufacturing, it is advantageous if the plastic casing is a plastic encapsulation enclosing the coil in sections, in particular a "pre-encapsulation".

Advantageously, a deflecting element is arranged for deflecting the electrical conductor in the deflection region. The deflecting element is used to attach the coil. The conductor is at least partially guided around the deflecting element. For example, the deflection element is part of a drum-like coil support arranged inside the coil, which is produced from a heat-resistant thermoplastic. Such an arrangement contributes in a particularly advantageous manner to the mechanical stability of the overall structure.

In a further development of the invention, it is provided to provide a plurality of further layers of the coil forming coil sections, wherein between the individual coil sections lying deflection areas are arranged. In the respective deflection regions, the electrical conductor forming the coil is deflected in such a way that each of the helices formed by the coil sections has the same winding direction. In other words, it is intended to form the coil in multiple layers. According to the basic idea of the invention, the particularly compact design of the multilayer coil is achieved in that each layer of the coil has the same winding direction. The turns of the radially inwardly applied to a further layer of the coil coil sections are arranged in the intermediate regions between the turns of the outer layer.

It is understood that a coil formed in this way can have any number of layers in order, if necessary, to generate a sufficiently large electromagnetic field in the interior of the coil while at the same time minimizing the space available in particular in the radial direction.

The heating element arranged inside the coil is preferably substantially tubular and flows through the fluid flow in order to provide a sufficiently good thermal coupling.

Preferably, the coil is made of copper round wire with a thickness of less than 1 mm. The wall thickness of the plastic wrap, the bobbin and the shield case is typically less than 1 mm each.

It is envisaged to provide the adjusting device according to the invention in internal combustion engines, in particular in internal combustion engines of motor vehicles. The adjusting device according to the invention is particularly suitable for taking over the control of the supply of a fuel for the internal combustion engine. Especially in the field of motor vehicle construction space is limited, making compact designs are desirable. The heating device of the adjusting device is suitable for heating the hydrocarbonaceous fuel, if necessary, in order to improve the cold starting properties or to minimize a pollutant emission of the internal combustion engine.

In particular, in alternative drives, which use an alcohol as a fuel or an alcoholic fuel mixture as the drive means, such heating has proved to be advantageous, since such fuels generally have only moderately good cold-starting properties. In particular, with a view to the progressive development of alternative drives, it is desirable to simultaneously minimize pollutant emission.

The coil of the heating device is formed by the fact that the electrical conductor is wound over a spreading core in a rotational direction with simultaneous displacement in the axial direction. Subsequently, the conductor is deflected in a deflection and the outer layer of the coil wound. This is done by forming the second coil section forming the outer layer by winding the conductor against the original direction of rotation with simultaneous displacement against the original axial direction. The first and the second coil portion of the coil thus formed have helices with the same winding direction, whereby the particularly compact design is possible.

In a subsequent manufacturing step, the coil is partially encapsulated with a heat-resistant thermoplastic such as polyphenyl sulfide. This contributes to the mechanical stability and thermo-mechanical robustness of the actuator. Furthermore, an electrical insulation is thus provided between the coil and the rail-shaped contact element, which in a further method step is electrically conductively connected to the coil by means of resistance welding in the deflection region.

The coil is arranged in the substantially cylindrical shielding housing. The shield housing is made of a metal and forms an outer magnetic circuit to shield the magnetic field to the outside. The rail-shaped contact element is placed in the longitudinal recess of the shielding housing in order to optimally use the available space.

Then the coil is overmolded with the shielding housing arranged above it with thermoplastic material. In this case, an outer housing of the adjusting device is formed by means of an injection molding process, which provides adequate protection of the components arranged in the interior against liquid or gaseous media, in particular fuel mixtures.

In the following an embodiment of the invention will be explained in more detail with reference to drawing figures. Showing:

1 a greatly simplified schematic sectional view of an injection device according to the invention designed as actuating device;

2 a side view of a coil used in the adjusting device according to the invention with a rail-like return element;

3 a detailed view in the direction of arrow III, according to 2 ;

4 a perspective view of a coil used in an adjusting device according to the invention with a return element, which is formed from a wire loop;

5 a side view according to 4 ;

6 a detailed view in the direction of arrow VI according to 5 ;

7 a section along section line VII in 6 ,

Corresponding parts are provided in all figures with the same reference numerals.

1 shows a sectional view of an electromagnetic actuator 1 , which is designed as an injection nozzle for use in a motor vehicle. The adjusting device 1 is intended to control the supply of a hydrocarbon-containing fuel, in particular alcohol in an internal combustion engine. For the invention, not essential parts of the adjusting device are in 1 not shown.

At a front, pointing in the direction of the engine end of the actuator 1 is a heater 2 arranged a coil 3 and one inside the coil 3 arranged heating element comprises, which is not shown in detail in the drawing figures. The heating element is made of a metal and formed substantially tubular. During operation of the adjusting device 1 the heating element is flowed through by a fluid flow of the hydrocarbon-containing fuel. The heating element is by means of the coil 3 inductively heated. This is done by means of electromagnetic induction inside the coil 3 , which is designed to generate an electromagnetic field of sufficiently great strength in the interior.

The sink 3 surrounds a coil carrier 4 made of polyphenyl sulfide by an injection molding process.

The sink 3 is from a plastic cladding 5 surrounded in sections, which was injected by means of a pre-injection. The plastic wrap 5 consists in the exemplary embodiment shown also from polyphenyl sulfide to ensure a sufficiently good thermo-mechanical stability. The plastic wrap 5 also serves to electrically isolate the coil 3 from a rail-shaped contact element 6 , which in a deflection area 7 the coil 3 with the coil 3 is electrically connected. The provision of the electrically conductive connection between coil 3 and contact element 6 takes place by means of a resistance welding and serves for the parallel connection of a first coil section 8th with a second coil section 9 the coil 3 , The first coil section 8th forms an inner layer of the coil 3 which of which is the outer layer of the coil 3 forming the second coil section 9 is surrounded.

The parallel connection of the two coil sections 8th . 9 the two-ply coil 3 serves to minimize the electrical resistance so that from the coil 3 generate electromagnetic fields which are adapted to inductively heat the heating element arranged in the interior.

A substantially cylindrical shielding housing 10 surrounds the coil 3 and their plastic wrap 5 except for the area around the contact element 6 , There has the shield case 10 a longitudinal recess 11 on that in detail in 3 and 4 is shown. The shield housing 10 is made of metal and forms the shield of the coil 3 generated magnetic field an outer iron circle.

The heater 2 also has an outer housing 12 made of plastic, which is formed by means of an injection molding process. The housing 12 has a connection part 13 with connection elements arranged therein 14 for supplying an electric current for controlling the coil 3 and another coil 15 serves. The further coil 15 is adapted to the movement of one inside the adjusting device 1 arranged and not shown to control armature to regulate the fuel supply. The further coil 15 is on another coil carrier 16 arranged.

The sink 3 is from the plastic cladding 5 partially surrounded, which has a thickness of 0.35 to 0.5 mm in the exemplary embodiment shown.

Accordingly, in the exemplary embodiment, the coil 3 made of copper round wire, which has a diameter of about 0.63 mm.

Radially outward closes the shield housing 10 on, the wall thickness, for example, is about 0.9 mm. The entire assembly is from the outer housing 12 surrounded for protection against external influences.

At the in 2 shown side view of the coil 3 is clearly an uppermost winding section of the first coil section 8th and the entire second coil section 9 to see.

For parallel connection of the two coil sections 8th and 9 is in the deflection area 7 the lowest winding of the first coil section 8th deflected and returned so that they are in the lowest winding 9 ' of the second coil section 9 goes over and then back to the connection element 14 is guided. Both the first coil section 8th as well as the second coil section 9 have the same winding direction, so that an arrangement of the turns is possible, in which the turns of the inner layer of the first coil section 8th in the recesses of the turns of the outer layer forming second coil section 9 are arranged. This results in the invention according to the desired very slim design of the coil.

In the deflection area 7 is the rail-shaped feedback element 6 contacted with the returning copper wire portion, in particular welded and thus forms a common lower terminal for the first and the second coil portion 8th . 9 ,

In 3 is again clearly the lowest turn 8th' of the first coil section 8th shown, the coming out of this section copper wire is in the deflection 7 U-shaped deflected and runs back into the lowest turn 9 ' of the second coil section 9 ,

Referring now to the drawings 4-7, there is shown a modified embodiment relating to the arrangements of the turns of the first and second coil sections 8th . 9 Although essentially the same design, ie here are the turns corresponding to each other, but that is in the 1 - 3 provided rail-shaped return element 6 replaced by that the return element 6 through conductor sections 6 ' is replaced, in the axial direction of the coil sections 8th . 9 , ie in the longitudinal direction of the coil 3 to the upper terminal 15 the adjusting device 1 run. As a result, the separate line or rail-shaped return element 6 omitted, the return is almost by a continuous wire loop, according to 5 . 6 and 7 within the turns of the second coil section 9 is led upwards. This means for the manufacturing process that initially the first coil section 8th is wound, then the winding wire over the deflection 7 is placed, as shown in 4 in the arrow direction 20 is placed in the axial direction upwards and then back down to a loop 21 to build. In the area of the loop 21 is the wire to a connection element of the actuator 1 connected.

It should be noted that the two upper ends of the coil sections 8th and 9 interconnected and on another connection element 14 are placed so that the two coil sections 8th . 9 can be operated in parallel.

In 7 is again shown in section, as the turns of the first and the second coil section 8th . 9 on the bobbin 4 are attached and how the return element 6 in the form of in the axial direction 20 returned wire loop 21 within the turns of the second coil section 9 is arranged.

Claims (26)

Adjusting device ( 1 ) for the passage of a fluid wherein the adjusting device ( 1 ) is designed as a fuel injection nozzle, with an inductive heating device ( 2 ), which has a current-carrying coil ( 3 ) and at least in sections within the coil ( 3 ) arranged heating element, which by means of the coil ( 3 ) is inductively heated and for the transfer of heat thermally to the inside of the adjusting device ( 1 ) is coupled to the fluid flow, wherein the coil ( 3 ) at least one multi-turn first coil section ( 8th ) and at least one further multiple coil turn second coil section ( 9 ), wherein the first coil section ( 8th ) at least one within the second coil section ( 9 ) arranged position, characterized in that a coil ( 3 ) forming a helically arranged electrical conductor in a between the first and the second coil section ( 8th . 9 ) arranged deflection region ( 7 ) is formed such that from the first coil section ( 8th ) has the same winding direction as the winding direction of the second coil section ( 9 ) formed in the interior of the second coil section ( 9 ) arranged helically arranged conductor of the first coil section ( 8th ) is arranged in the region of the recesses which, between the individual turns of the second coil section (FIG. 9 ) are formed. Adjusting device according to claim 1, characterized in that the winding direction of the first and the second coil portion ( 8th . 9 ) is left-handed or the winding direction of the first and the second coil section ( 8th . 9 ) is right-handed. Adjusting device according to claim 1 or 2, characterized in that the winding direction of the first and the second coil portion ( 8th . 9 ) when viewing the coil sections ( 8th . 9 ) reverses in the same axial direction. Adjusting device according to claim 1-3, characterized in that the pitch of the coil ( 3 ) in the first and in the second coil section ( 8th . 9 ) is equal to. Adjusting device according to one of the preceding claims, characterized in that the first and the second coil section ( 8th . 9 ) are connected in parallel to each other. Adjusting device according to claim 5, characterized in that for parallel connection of the coil sections ( 8th . 9 ) a return element is provided, which with the coil ( 3 ) in the deflection area ( 7 ) is electrically connected. Adjusting device according to claim 6, characterized in that the return element is rail-shaped, in particular highly conductive, is formed. Adjusting device according to one of the preceding claims 1-6, characterized in that the return element by conductor sections of the coil sections ( 8th . 9 ) formed in the axial direction of the coil sections ( 8th . 9 ) to a connection element ( 14 ) of the adjusting device ( 1 ). Adjusting device according to claim 7, characterized in that the coil ( 3 ) in a substantially cylindrical shielding housing ( 10 ) is arranged, which has a longitudinal recess ( 11 ), in which the rail-shaped contact element ( 6 ) or the conductor sections are arranged. Adjusting device according to one of claims 7 to 9, characterized in that the contact element ( 6 ) by means of a resistance welding with the coil ( 3 ) connected is. Adjusting device according to one of the preceding claims, characterized in that the contact element ( 6 ) and the coil ( 3 ) in sections by means of a plastic sheath ( 5 ) are electrically isolated from each other. Adjusting device according to claim 11, characterized in that the plastic sheath ( 5 ) comprises a heat-resistant thermoplastic, in particular polyphenylsulfide. Adjusting device according to claim 11 or 12, characterized in that the plastic sheath ( 5 ) one the coil ( 3 ) Envelope enveloping plastic extrusion is. Adjusting device according to one of the preceding claims, characterized in that for deflecting the electrical conductor in the deflection region ( 7 ) a deflecting element ( 16 ) is arranged. Adjusting device according to one of the preceding claims, characterized in that further layers of the coil ( 3 ) forming coil sections with intermediate deflection areas ( 7 ) are provided, in which deflection areas ( 7 ) the coil ( 3 ) is deflected such that each of the helices formed by the coil sections has the same winding direction. Adjusting device according to one of the preceding claims, characterized in that the heating element is substantially tubular and flows through the fluid flow. Adjusting device according to one of the preceding claims, characterized in that the the return element ( 6 ' ) forming conductor sections or the rail-shaped contact element ( 6 ) within at least one outer coil section. Actuating device according to one of the preceding claims, characterized in that the return element ( 6 ) forming conductor sections ( 30 ) by a conductor loop ( 21 ) between the first and second coil sections ( 8th . 9 ) are formed. Use of the adjusting device ( 1 ) according to one of the preceding claims in an internal combustion engine, in particular in an internal combustion engine of a motor vehicle, characterized in that the actuating device ( 1 ) is used to control the tempered or gaseous supply of a fuel. Use of the adjusting device according to claim 19, characterized in that the fuel is an alcohol. Method for producing an adjusting device ( 1 ) according to one of claims 1 to 18, with a coil ( 3 ) having heating device ( 2 ), characterized in that an inner layer of the coil ( 3 ) forming the first coil section ( 8th ) is formed by winding an electrical conductor over an expansion core in one direction of rotation with simultaneous displacement in the axial direction, the conductor in a deflection region (FIG. 7 ) is deflected and an outer layer of the coil ( 3 ) forming the second coil section ( 9 ) is formed by winding the conductor in the opposite direction to the direction of rotation while being displaced in the opposite direction to that of the first and second coil sections ( 8th . 9 ) have the same winding direction. Method according to claim 21, characterized in that the coil ( 3 ) is partially encapsulated with a heat-resistant thermoplastic. A method according to claim 21 or 22, characterized in that a rail-shaped contact element ( 6 ) with the coil ( 3 ) by means of a resistance welding electrically conductive in the deflection region ( 7 ) is connected. A method according to claim 21 or 22, characterized in that the conductor starting from the deflection ( 7 ) between the first and second coil sections ( 8th . 9 ) as a conductor loop ( 21 ) is formed along the coil longitudinal axis ( 20 ) to a connection area ( 14 ) and a common connection of the parallel-connected first and second coil sections ( 8th . 9 ) contacted. Method according to claim 23, characterized in that the coil ( 3 ) in a metallic and substantially cylindrical shielding housing ( 10 ) is arranged such that the rail-shaped contact element ( 6 ) in a longitudinal recess ( 11 ) of the shielding housing ( 10 ) is arranged. Method according to claim 25, characterized in that around the coil ( 3 ) and the shield case ( 10 ) an outer housing ( 12 ) is formed from plastic by means of an injection molding process.

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