DE102008042686A1 - Magnetic coil, motor vehicle component with magnetic coil and use - Google Patents

Abstract

The invention relates to a coil (18) wound from a coil wire (22), in particular for a motor vehicle component. According to the invention, it is provided that the cross-sectional area of the coil wire (22) is contoured in a square manner.

Description

State of the art

The The invention relates to a coil wound from a coil wire, in particular for a motor vehicle component, such as a fuel injector, a solenoid valve or a sensor according to the preamble of claim 1, a motor vehicle component with a magnetic coil according to claim 8 and a use according to claim 10th

From the DE 10 2006 058 073 A1 For example, a solenoid valve for a fuel injection system is known. This comprises an electromagnetic actuator with a wound from a coil wire magnetic coil. The coil wire has a circular contoured cross-sectional area and is provided with a, usually applied in the wet-coating process, insulation. The copper fill factor (winding density) of known magnetic coils for the automotive sector is about 63%, which adversely affects the space requirement and the maximum achievable power density.

Out Japanese entertainment industry are insulated coil wires (Winding wires) with a rectangular cross-section known. These typically have a width / thickness ratio two to five and are with insulation wall thicknesses provided by having less than 10 microns insulating layers, wherein the insulating layers typically by electrostatic methods be applied.

Disclosure of the invention

Technical task

Of the Invention is based on the object, with respect to the space requirement optimized magnetic coil, in particular for a motor vehicle component to specify. Preferably, with the magnetic coil large power densities be feasible. Furthermore, the object is a motor vehicle component, such as a fuel injector, a solenoid valve or a sensor to provide with a correspondingly optimized magnetic coil.

Technical solution

These Task is with respect to the solenoid with the characteristics of Claim 1 and by a use according to claim 10 solved. With regard to the motor vehicle component is the problem solved by the features of claim 8. advantageous Further developments of the invention are in the subclaims specified. All fall within the scope of the invention Combinations of at least two of in the description, the claims and / or features disclosed in the figures.

The invention has recognized that large coil wire fill factors (winding densities), in particular copper fill factors, can not be realized with circularly contoured coil wires. Furthermore, the invention has recognized that even rectangular contoured coil wires do not lead to optimal Spulendrahtfüllfaktoren, since at least in areas of the winding layer transitions unfilled areas result that are larger with increasing wire width due to the then inevitably in the heat increasing winding pitch. The invention is based on the idea of using coil wires (winding wires) with a square cross-section for producing a magnet coil, in particular for the motor vehicle sector, thereby avoiding unfilled gussets and minimizing unfilled areas at the winding layer junctions. In addition, square coil wires basically have a more favorable volume surface ratio than rectangular coil wires and thus with the same insulation wall thickness a lower need for insulation material. This also accommodates the demand for a large coil wire fill factor. A trained according to the concept of the invention solenoid is particularly suitable for modern diesel injection technology with increasing demands on consumption, CO ₂ emission and particulate emission. These requirements are met only highly dynamic fuel injectors with short switching times for the realization of a multipoint injection, with which also high magnetic forces to control the increasing diesel pressures can be realized. Quite essential here is the minimization of the required installation space, which can be realized with a coil wire shaped according to the concept of the invention in a square cross-section. A trained according to the concept of the invention magnetic coil can be realized with an extremely compact electrical winding with a high coil wire fill factor, in particular Kupferfüllfaktor, sufficiently large wire cross section and low number of turns. Preferably, the edge length of the coil wire is chosen so that it is optimally adapted to the winding window and the windings of this, at least approximately, completely fill.

In Development of the invention is provided with advantage that the Coil wire is provided with an insulating layer by an electrostatic process is applied. This can be very uniform insulation layers with layer thicknesses of 10 μm or less can be achieved.

Particularly preferred is an embodiment in which the coil wire is wound on a coil carrier, preferably made of plastic, wherein the coil wire particularly preferably with egg ner, in particular as Finalumspritzung (protective layer of plastic) formed, preferably thin-walled, envelope is provided, preferably in order to protect the coil wire from corrosive media, such as fuel, optimally. It is particularly preferred if the sheath has a wall thickness of less than 200 microns, preferably less than 175 microns, more preferably of about 150 microns or less. This can be achieved particularly well by the use of highly flowable thermoplastics (for example, modified polyphenylene sulfide trade name Ryton R4 or Xtel XK 2340). Through the use of highly flowable thermoplastics, the necessary process pressure and the necessary process temperature for realizing the final extrusion can be reduced so far that thermal and / or mechanical damage to the coil wire and / or displacement of the coil wires of the uppermost winding are avoided. It is also conceivable to realize the enclosure by casting with reaction resin.

Especially preferred is an embodiment in which the coil wire fill factor, especially the copper fill factor, larger than 70%, preferably greater than 80%, especially preferably greater than 90%.

optimal Power densities can be achieved with a coil wire, the inside of the insulating layer a square in cross-section contoured Copper core has.

The Invention also leads to a motor vehicle component with at least a trained according to the concept of the invention magnetic coil. The motor vehicle component is particularly preferably to a fuel injector or to a solenoid valve, in particular a control valve (servo valve) of the fuel injector. This can by providing a trained according to the concept of the invention Magnet coil can be realized with a minimal space requirement. In addition, high power densities and thus high magnetic forces realizable. Furthermore, it may be in the motor vehicle component, for example to a solenoid valve, for example, an ABS and / or driving dynamics valve or act around a hydraulic valve. Also, the use of a formed according to the concept of the invention magnetic coil in dynamic electromagnetic sensors, in particular in the automotive sector realizable.

About that In addition, the invention leads to the use of a square contoured, in particular a copper core having wire to Winding a magnetic coil, in particular for a motor vehicle application. Preferably, the solenoid is in a fuel injector, a Solenoid valve or an electromagnetic sensor integrated.

Brief description of the drawings

Further Advantages, features and details of the invention will become apparent the following description of preferred embodiments as well as from the drawings. These show in:

1 in a schematic, fragmentary illustration of a fuel injector with a solenoid coil having a control valve (servo valve), and

2 a sectional view of a solenoid coil and an enlarged view of the cross section of the coil wire of the coil winding.

embodiments the invention

In The figures are the same elements and elements with the same Function marked with the same reference numerals.

In 1 is a fragmentary fuel injector 1 (Common rail injector) shown for injecting fuel into a combustion chamber of an internal combustion engine, not shown. The fuel injector 1 comprises an adjustable between an open position and the fuel flow into the combustion chamber releasing opening position injection valve element 2 , which can be made in one piece or in several parts. With its upper end in the plane of the drawing is the injection valve element 2 in a sleeve-shaped section 3 a throttle plate 4 guided and limited with its upper side in the drawing plane 5 one within the sleeve-shaped portion 3 trained control chamber 6 ,

The control chamber 6 is via an inlet throttle 7 permanently hydraulically with a substantially under pressure rail pressure chamber 8th of the fuel injector 1 connected. From the control chamber 6 opens an outlet throttle 9 out, which is the control chamber 6 with a valve chamber 10 connects, the radially outward of a sleeve-shaped control valve element 11 a control valve 12 (Servo valve) is limited. With the help of the control valve 12 is the valve chamber 10 and thus the control chamber 6 hydraulically with a low pressure area at low pressure 13 of the fuel injector 1 connected, which is connected via a return connection, not shown, to a reservoir, also not shown. The valve chamber 10 is in the axial upward direction of a pressure pin 14 bounded by the top of the plane in a centric bore 15 the control valve element 11 protrudes.

For axial adjustment of the control valve element 11 is an electromagnetic actuator 16 provided, one on a bobbin 17 arranged magnetic coil 18 includes.

When the solenoid is energized 18 becomes one-piece with the control valve element 11 trained anchor plate 19 in the drawing plane upwards in the direction of the electromagnetic actuator 16 adjusted, reducing the fuel flow from the control chamber 6 in the low pressure area 13 and is released from there to the return port. The flow cross sections of the outlet throttle 9 and the inlet throttle 7 are matched to one another in such a way that when the control valve is open 12 a net outflow of fuel from the control chamber 6 results, with the result of a rapid pressure drop, which in turn for an opening direction of the injection valve element 2 acting hydraulic opening force ensures, so that the injection valve element 2 lifts off from its injection valve element seat, not shown.

To end the injection process, the energization of the solenoid 18 interrupted, causing the control valve element 11 with the help of a closing spring 20 again on his at the throttle plate 4 trained control valve seat 21 is adjusted. The over the inlet throttle 7 inflowing fuel causes a pressure increase in the control chamber 6 and thus for a closing movement of the injection valve element 2 ,

As it turned out 1 gives, is the magnetic coil 18 from a wound coil wire 22 formed, which has a cross-sectionally square peripheral contour. This allows a high Spulendrahtfüllfaktor within a coil carrier 17 formed circumferential groove 23 (Winding window) can be achieved. It can be seen that the circumferential groove 23 radially outward from an axially extending annular final injection 24 (thin-walled envelope) is closed in the radial direction. This prevents direct contact of the coil wire 22 with fuel. The wall thickness of the final extrusion 24 in the radial direction is about 150 microns in the embodiment shown. With radial distance to the final encapsulation 24 is an inner, the circumferential groove 23 limiting peripheral wall 25 of the bobbin 17 to recognize. The wall thickness of this peripheral wall 25 is also about 150 microns.

In 2 is a cross section through a solenoid 18 shown. You can see this by winding a coil wire 22 formed coil winding. 2 can be seen that the windings of the coil wire 22 fit snugly against each other, so that a high Spulendrahtfüllfaktor is achieved. In the embodiment shown, the width B of the magnetic coil 18 about 2.0 mm and the height H is about 1.2 mm. From the detailed representation in the drawing plane according to 2 top right results in the cross-sectional contour of a coil wire 22 , To recognize is a square contoured copper core 26 that of a circumferentially closed insulation layer 27 is surrounded. The insulation layer 27 can be applied in an electrostatic process.

The side length 1 of the copper core 26 is in the illustrated embodiment about 0.187 mm and the side length L of the entire coil wire 22 about 0.20 mm. Thus, the wall thickness of the insulation layer 27 about 0.013 mm.

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• - DE 102006058073 A1 [0002]

Claims (10)

From a coil wire ( 22 ) wound magnet coil ( 18 ), in particular for a motor vehicle component, characterized in that the cross-sectional area of the coil wire ( 22 ) is contoured square. Magnetic coil according to claim 1, characterized in that the coil wire ( 22 ) with an electrostatically applied insulation layer ( 27 ) is provided. Magnetic coil according to one of claims 1 or 2, characterized in that the coil wire ( 22 ) on a bobbin carrier ( 17 ) and with one, in particular as final injection ( 24 ) or formed as a reaction resin layer, preferably thin-walled, envelope is provided. Magnetic coil according to claim 3, characterized in that the wall thickness of the final encapsulation ( 24 ) is less than 200 microns, preferably less than 175 microns and / or about 150 microns. Magnetic coil according to one of claims 3 or 4, characterized in that the final encapsulation ( 24 ) is formed from a highly flowable thermoplastic, in particular modified polyphenylene sulfide (PPS). Magnetic coil according to one of the preceding claims, characterized in that the coil wire fill factor greater than 70%, preferably larger than 80%, most preferably greater than 90% is. Magnetic coil according to one of the preceding claims, characterized in that the coil wire ( 22 ) a copper core ( 26 ) having. Motor vehicle component with a magnet coil ( 18 ) according to any one of the preceding claims. Motor vehicle component according to claim 8, characterized in that the motor vehicle component is a fuel injector ( 1 ), a solenoid valve, or a dynamic electromagnetic sensor. Use of a coil having a square contoured cross-sectional area ( 22 ) for winding a magnetic coil ( 18 ), in particular for a motor vehicle component.