Internal-combustion engines – Charge forming device – With fuel pump
Patent
1987-11-06
1989-08-15
Miller, Carl Stuart
Internal-combustion engines
Charge forming device
With fuel pump
123494, 123500, 2511291, F02M 3900
Patent
active
048564826
DESCRIPTION:
BRIEF SUMMARY
PRIOR ART
In fast-acting solenoid valves, which are used, for example, for controlling diesel injection pumps, it is necessary to keep the opening and closing times and the end of the opening of tee valve needle as accurate as possible in order to determine the quantity of fuel that is supplied as precisely as possible. In order to achieve particularly short switch-off times (opening), the exciting current of the electromagnetically actuated valve is decreased as quickly as possible starting from the holding current value and is even briefly forced into the negative area in order to overcome the disadvantageous magnetic adhering. Recognizing the closing time from the current and/or voltage curves on the excited valve is relatively simple, since, in this case, a great change in speed of the valve needle occurs with a relatively small air gap and strong excitation of the magnetic circuit, which results in a change in induction which can be evaluated in a reliable manner. On the other hand, the evaluation of the opening process is substantially less reliable, since a stop results when there is a large air gap, and the excitation is substantially smaller because of the current reduction. In very fast-acting valves, the exciting current is often reduced to zero already before, or at the latest during, the needle movement, so that an evaluation of the opening process with the aid of characteristic current and voltage values is no longer possible at all.
ADVANTAGES OF THE INVENTION
In contrast, the method according to the invention, with the characterizing features of the main claim, has the advantage that the switch-off behavior of the electromagnetic valve can also be determined in a simple manner by means of the characteristic current or voltage curve so that the functioning of the combustion engine can be controlled in a more precise way.
Developments of the method and of circuit arrangements for implementing the method are indicated in the subclaims.
DRAWING
The method and circuit arrangements suitable for implementing the method are shown in a simplified manner with the aid of the drawing and are explained in more detail in the following description.
FIG. 1 shows a fuel injection pump in a simplified presentation;
FIG. 2 shows a diagram showing exciting current, exciting voltage and the path of the valve needle with conventional controlling of a valve;
FIG. 3 shows a diagram which shows the exciting current, the path of the valve needle and the curve of the exciting voltage, as a function of time in each instance, with the use of the method according to the invention;
FIG. 4 shows a block wiring diagram of a circuit arrangement for implementing the method according to the invention;
FIGS. 5 and 6 show additional diagrams of the type described more closely in the context of FIG. 3 in order to explain developments of the invention;
and FIGS. 7, 8 and 9 each show a circuit arrangement for implementing the method according to the invention.
DESCRIPTION OF THE EMBODIMENT EXAMPLE
In the fuel injection pump shown in FIG. 1, for example, a bush 2 is arranged in a housing 1, a pump plunger 3 executes a reciprocating and simultaneously rotating motion in this bush 2. The pump plunger 3 is driven by means of a cam drive 4 via a shaft 5 which rotates synchronously with the rate of rotation of the combustion engine provided with fuel by the injection pump. The front face of the pump plunger 3 and the bush 2 define a pump work space 6 which is connected with an inlet chamber or suction space 8 in the housing 1 of the fuel injection pump via a supply duct 7. The suction space 8 is supplied with fuel from a fuel container 10, for example, by means of a delivery pump 9. The fuel is distributed to pressure lines 12 from the pump work space 6 via an elongated distributor groove 11 of the pump plunger 3 when the pump plunger 3 is in the corresponding rotational position; the pressure lines 12 lead to injection nozzles 13 at the combustion engine via the bush 2 and the housing 1. A discharge duct 16 branches from the
REFERENCES:
patent: 3942485 (1976-03-01), Suda
patent: 3982505 (1976-09-01), Rivere
patent: 4112477 (1978-09-01), Sherwin
patent: 4392632 (1983-07-01), Gast
patent: 4718391 (1988-01-01), Rembold
patent: 4727835 (1988-03-01), Kobayashi
Linder Ernst
Rembold Helmut
Teegen Walter
Miller Carl Stuart
Robert & Bosch GmbH
Striker Michael J.
LandOfFree
Method of controlling the demagnetization phase of electromagnet does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method of controlling the demagnetization phase of electromagnet, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method of controlling the demagnetization phase of electromagnet will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-114586