EP1706634A1

EP1706634A1 - Method for production of a fuel injection valve and fuel injection valve

Info

Publication number: EP1706634A1
Application number: EP04801921A
Authority: EP
Inventors: Ferdinand Reiter; Martin Maier
Original assignee: Robert Bosch GmbH
Current assignee: Robert Bosch GmbH
Priority date: 2003-12-23
Filing date: 2004-11-10
Publication date: 2006-10-04
Anticipated expiration: 2024-11-10
Also published as: CN1898467A; DE10360774A1; EP1706634B1; JP4096008B2; BRPI0406513A; JP2006510852A; CN100449141C; WO2005064148A1; DE502004009983D1

Abstract

The invention relates to a fuel injection valve with a valve longitudinal axis (10), a fuel inlet nozzle (41), a valve closing body which moves axially along the valve longitudinal axis (10) and cooperates with a valve seat, provided on a valve seat body and at least one spray opening, downstream of the valve seat. The fuel inlet nozzle (41), made from a thin-walled tube (44), runs, starting at an inlet opening (60), with an upstream section (62) at an angle (A) to the valve longitudinal axis (10) which is larger than 0° and less than or equal to 90°. The fuel inlet nozzle (41) finally terminates at the downstream section (63) thereof on the valve longitudinal axis (10). The fuel injection valve is particularly suitable for application in fuel injection units in mixture-compressing, spark-ignited, internal combustion engines.

Description

Method of manufacturing a fuel injector and fuel injector

State of the art

The invention relates to a method for producing a pulp injection valve according to the preamble of claim 1 and a fuel injection valve according to the preamble of claim 5.

1 shows a known fuel injector from the prior art

Technology shown, which has a classic top feed structure, which is characterized in that all the flow-guiding components of the

The ice injection valve extends in alignment along a longitudinal valve axis, the flow inlet being connected to a connecting piece of a fuel distributor and the flow outlet downstream of the sealing seat

Intake pipe or is directed directly into a combustion chamber of an internal combustion engine.

From DE 21 53 286 AI a fuel injector is already known which can be actuated electromagnetically in a conventional manner. The injection valve has an inlet connection which is arranged off a longitudinal axis of the valve. The injection valve also has a housing body in which all relevant valve components are installed, so that fuel can be supplied under pressure between the inlet connector and a fuel outlet to a valve seat with which a valve closing body interacts. The case body will on the inflow side covered with a cover-like closure body which, in addition to the inlet connector, also has an outlet connector aligned with the longitudinal axis of the valve for excess fuel and electrical plug contacts. The closure body is held firmly on the housing body by a flanged edge of the housing body encompassing the closure body. A sealing ring is also provided in the connection area between the closure body and the housing body.

Advantages of the invention

The method according to the invention for producing a pulp injection valve with the characterizing features of claim 1 has the advantage that fuel injectors with low overall heights for cramped conditions, e.g. can be produced on motorcycles. It is particularly advantageous that the brake fuel injection valve according to the invention with the characterizing features of claim 5 is already completely set in the actual functional part of the injection valve with respect to the stroke of the axially movable valve part and the dynamic and static flow rate, so that subsequently there is no problem

Assembly of an angled fuel inlet connector that even deviates from the alignment of the valve longitudinal axis in a connecting part of the injection valve on the functional part can be carried out by firm connection.

In a particularly advantageous manner, fuel injection valves can be produced which have fuel inlet connections, the angle of which to the longitudinal axis of the valve is variable between 0 ° and 90 °.

Such an inlet connector, which is angled on one side, also very simply offers the possibility of precise positioning of the injection valve or a simplified rotation fixation.

The measures listed in the subclaims provide advantageous developments and improvements to that specified in claim 1 Method or the fuel injector specified in claim 5 possible.

Ideally, the fuel inlet connection is provided with a sawtooth-like profile at its upstream end, so that a simple connection with a fuel supply hose, which is pushed onto the sawtooth-like profile, and a hose clamp is made possible. In this way, additional sealing measures, such as O-rings, can be omitted.

drawing

An embodiment of the invention is shown in simplified form in the drawing and explained in more detail in the following description. FIG. 1 shows a fuel injection valve according to the prior art with a top feed supply that is aligned with the longitudinal axis of the valve

Fuel, Figure 2 with a fuel inlet connector

Hose connection option and also aligned with the valve longitudinal axis

Fuel supply and FIG. 3 a brake fuel inlet connection with hose connection possibility and fuel supply angled by approximately 90 ° to the longitudinal axis of the valve.

Description of the embodiments

Before the method steps of the method for producing a fuel injection valve are described with reference to FIGS. 2 and 3, the basic structure of a fuel injection valve of the prior art, which is designed as a so-called top-feed injection valve, is to be explained in more detail with reference to FIG. 1.

The electromagnetically actuated valve in the form of an injection valve for fuel injection systems of mixture-compressing, spark-ignited internal combustion engines shown by way of example in FIG. 1 has one of a largely tubular tubular core 2, which serves as an inner pole and partially serves as fuel flow. The magnetic coil 1 is made of an outer, sleeve-shaped and stepped, z. B. ferromagnetic valve jacket 5, which serves as an outer pole outer magnetic circuit component, completely surrounded in the circumferential direction. The

Solenoid 1, the core 2 and the valve jacket 5 together form an electrically excitable actuating element.

While the magnet coil 1 embedded in a coil former 3 surrounds a valve sleeve 6 from the outside, the core 2 is introduced into an inner opening 11 of the valve sleeve 6 which is concentric with a longitudinal axis 10 of the valve.

The e.g. Ferritic valve sleeve 6 is elongated and thin-walled.

The opening 11 serves inter alia. as a guide opening for one along the

Longitudinal valve axis 10 axially movable valve needle 14. The valve sleeve 6 extends in the axial direction e.g. about half of the total axial extent of the fuel injector.

In addition to the core 2 and the valve needle 14, a valve seat body 15 is also arranged in the opening 11, which is attached to the valve sleeve 6 e.g. is fixed by means of a weld 8. The valve seat body 15 has a fixed

Valve seat surface 16 as a valve seat. The valve needle 14 is formed, for example, by a tubular armature section 17, a likewise tubular needle section 18 and a spherical valve closing body 19, the valve closing body 19 being e.g. is firmly connected to the needle section 18 by means of a weld seam. On the downstream face of the

Valve seat body 15 is arranged, for example, a cup-shaped spray perforated disk 21, the bent and circumferential circumferential retaining edge 20 is directed upward against the direction of flow. The fixed connection of valve seat body 15 and spray orifice plate 21 is, for. B. realized by a circumferential dense weld. One or more transverse openings 22 are provided in the needle section 18 of the valve needle 14, so that fuel flowing through the anlcer section 17 can escape to the outside in an inner longitudinal bore 23 and flow along the valve closing body 19, for example along flats 24 as far as the valve seat surface 16. The injection valve is actuated electromagnetically in a known manner. For the axial movement of the valve needle 14 and thus for opening against the spring force of a return spring 25 engaging the valve needle 14 or closing the injection valve, the electromagnetic circuit is used with the

Solenoid coil 1, the inner core 2, the outer valve jacket 5 and the armature section 17. The armature section 17 is aligned with the core 2 with the end facing away from the valve closing body 19.

The spherical valve closing body 19 interacts with the valve seat surface 16 of the valve seat body 15 which tapers in the shape of a truncated cone and is formed in the axial direction downstream of a guide opening in the valve seat body 15. The spray hole disk 21 has at least one, for example four, spray openings 27 formed by eroding, laser drilling or punching.

The insertion depth of the core 2 in the injection valve is, among other things, decisive for the stroke of the valve needle 14. The one end position of the valve needle 14 when the solenoid coil 1 is not energized is fixed by the valve closing body 19 resting against the valve seat surface 16 of the valve seat body 15, while the other End position of the valve needle 14 when the solenoid coil 1 is excited results from the contact of the armature section 17 at the downstream core end. The stroke is adjusted by axially displacing the core 2, which is produced, for example, by a machining process such as turning, and which is subsequently firmly connected to the valve sleeve 6 in accordance with the desired position.

In addition to the return spring 25, an adjusting element in the form of an adjusting sleeve 29 is inserted into a flow bore 28 of the core 2, which runs concentrically to the longitudinal axis 10 of the valve and serves to supply the fuel in the direction of the valve seat surface 16. The adjusting sleeve 29 is used to adjust the

Spring preloading of the return spring 25 resting on the adjusting sleeve 29, which in turn is supported with its opposite side on the valve needle 14, whereby also an adjustment of the dynamic spray quantity with the Adjustment sleeve 29 takes place. A fuel filter 32 is arranged above the adjusting sleeve 29 in the valve sleeve 6.

The injection valve described so far is characterized by its particularly compact design. These components form a pre-assembled independent

Assembly, which is called functional part 30 below. The functional part 30 thus essentially comprises the electromagnetic circuit 1, 2, 5 as an actuator and a sealing valve (valve closing body 19, valve seat body 15) with a subsequent jet processing element (spray hole disk 21) and the valve sleeve 6 as a threaded body.

Regardless of the functional part 30, a second assembly is produced, which is referred to below as the connecting part 40. The connecting part 40 is characterized above all by the fact that it comprises the electrical and the hydraulic connection of the fuel injector. With the invention

In particular, method steps are intended to further increase the compactness of the entire fuel injector by specifically shaping the connecting part 40 by reducing the overall height of the fuel injector.

The connection part 40, which is partially designed as a plastic part, has a metal fuel inlet connector 41 and a tubular basic body 42 made of plastic which stabilizes, protects and surrounds this fuel inlet connector 41. A flow bore 43 of a tube 44 of the fuel inlet connector 41 which runs concentrically to the longitudinal axis 10 of the valve serves as

Fuel inlet and is flowed through by the fuel in the axial direction from the inflow end of the fuel injector.

A hydraulic connection of connection part 40 and functional part 30 is achieved in the fully assembled fuel injector in that the

Flow bores 43 and 28 of both assemblies are brought together so that an unimpeded flow of fuel is ensured. When the connecting part 40 is mounted on the functional part 30, a lower end 47 of the tube 44 projects into the opening 11 to increase the connection stability the valve sleeve 6 into it. The base body 42 made of plastic can be sprayed onto the functional part 30, so that the plastic immediately surrounds parts of the valve sleeve 6 and the valve jacket 5. A secure seal between the functional part 30 and the base body 42 of the connecting part 40 is achieved, for example, via a labyrinth seal 46 on the circumference of the

Valve jacket 5 achieved.

The base body 42 also includes an injection molded electrical connector 56. At its end opposite the connector 56, the contact elements are electrically connected to the magnetic coil 1.

FIGS. 2 and 3 partially show two connecting parts 40 with fuel inlet connecting pieces 41 in order to clarify the invention. In this case, it is again indicated in FIG. 2 that, in the case of conventional fuel injection valves, it is necessary to arrange the fuel inlet connection 41 axially parallel and in alignment with the valve longitudinal axis 10 in order to have access to appropriate adjustment tools at any time for the necessary adjustment measures within the valve.

The method according to the invention for producing a pulp injection valve is characterized in that it is possible to provide a fuel inlet connection 41 on the fuel injection valve which, starting from an upstream inlet opening 60, extends at an angle α to the valve longitudinal axis 10 which is greater than 0 ° and less than or equal to 90 ° is. An exemplary embodiment is shown in FIG. 3, in which the fuel inlet connector 41 is under a

Angle a of 90 ° to the valve longitudinal axis 10 extends in a first angled section 62. In this case, the inlet opening 60 spans a plane that runs parallel to the longitudinal axis 10 of the valve. Ultimately, the fuel inlet connector 41 ends with a second axially parallel section 63 on the valve longitudinal axis 10. In the ideal case, the section 63 of the fuel inlet connector 41 is aligned and thus coaxial with the valve longitudinal axis 10.

The fuel injector is manufactured in such a way that first the functional part 30 of the valve is manufactured, which includes the actuators 1, 2, 5 and the sealing valve 15, 19 comprises. For example, the valve sleeve 6 is provided as the base body. This manufacturing process is followed by an adjustment process in which the stroke of the axially movable valve part (valve needle 14, valve closing body 19) and the dynamic and static flow rate are already completely adjusted. Below is the

Fuel inlet connector 41 is firmly connected to functional part 30 in such a way that fuel inlet connector 41 ends on valve longitudinal axis 10. The fuel inlet connector 41 is inserted with its end 47 of the axially parallel section 63, for example, into the opening 11 of the valve sleeve 6 and subsequently on the valve sleeve 6 of the functional part 30 by welding, in particular

Laser welding attached. In addition to welding, other joining methods such as soldering, gluing or locking can also be used.

Around the angled metal pulp inlet connection 41, which e.g. a thin-walled tube 44 represents, to stabilize and protect the

In the following, fuel inlet connector 41 is extrusion-coated, for example, with the tubular base body 42 made of plastic. In this case, a molded connector plug 56 can also belong to the base body 42. Adequate stability and good protection of the fuel inlet connection 41 are already provided if the base body 42 only largely extends the axis-parallel one

Absclmitt 63 of the fuel outlet nozzle 41 surrounds, while the angled portion 62 of the tube 44 is exposed at its desired angle and is therefore not covered by plastic.

Ideally, the fuel inlet port 41 is sawtooth-like

Provide profile 61 at its upstream end in the area of the angled section 62, so that a simple connection with a fuel supply hose, not shown, which is pushed onto the sawtooth-like profile, and a hose clamp is made possible. In this way, additional sealing measures, such as O-rings, can be omitted.

Claims

Expectations

1. A method for producing a fuel injection valve which has a longitudinal valve axis (10), a fuel inlet connection (41), a valve closing body (19) which can be moved axially along the longitudinal valve axis (10) and which is provided with a valve seat (15) provided on a valve seat body (15). 16) cooperates, and has at least one spray opening (27) downstream of the valve seat (16), characterized in that

a functional part (30) of the valve is produced, which comprises an actuator (1, 2, 5) and a sealing valve (15, 19),

- This functional part (30) is set with regard to stroke and flow quantities,

- Separately, a fuel inlet connector (41) is provided, which starts from an inlet opening (60) at an angle (oc) to the valve longitudinal axis (10), which is greater than 0 ° and less than / equal to 90 °, and

- The fuel inlet connector (41) is firmly connected to the functional part (30) in such a way that the fuel inlet connector (41) ends on the valve longitudinal axis (10).

2. The method according to claim 1, characterized in that the fuel inlet connector (41) on a valve sleeve (6) of the functional part (30) is attached.

3. The method according to claim 2, characterized in that the fastening of the fuel inlet connection (41) is carried out by means of welding, in particular laser welding.

4. The method according to any one of claims 1 to 3, characterized in that the fuel inlet connector (41) is at least partially covered with a base body (42) made of plastic after it is fastened.

5. Fuel injection valve for fuel injection systems from

Porridge engines, with a longitudinal valve axis (10), with a fuel inlet connection (41), with a valve closing body (19) which can be moved axially along the longitudinal valve axis (10) and which cooperates with a valve seat (16) provided on a valve seat body (15), and with at least one spray opening (27) downstream of the valve seat (16), characterized in that the brake inlet fitting (41), starting from an inlet opening (60), extends at an angle (α) to the valve longitudinal axis (10) which is greater than 0 ° and is less than / equal to 90 ° and ultimately ends on the valve longitudinal axis (10).

6. The fuel injector according to claim 5, characterized in that the inlet opening (60) spans a plane which runs parallel to the valve longitudinal axis (10).

7. Fuel injection valve according to claim 5 or 6, characterized in that the fuel inlet connection (41) is formed by a thin-walled tube (44) which is at least partially embedded in a base body (42).

8. Fuel injection valve according to claim 7, characterized in that the base body (42) consists of a plastic.

9. The fuel injector according to claim 7 or 8, characterized in that the base body (42) only largely surrounds an axially parallel section (63) of the fuel outlet nozzle (41).

10. Fuel injection valve according to one of claims 5 to 9, characterized in that the fuel inlet connection (41) is provided at its upstream end with a sawtooth-like profile (61).