DE1807773A1 - Injection device for gasoline engines - Google Patents

Description

Injection device for gasoline engines

The invention relates to a device for indirect fuel injection for Otto gates, d. H. an institution where the f | Fuel does not enter the cylinder directly at high pressure, but rather at a significantly lower pressure in the intake manifold the inlet valves is injected. Mechanical gate directions for the variable total measurement of the fuel are due relatively complex due to the high precision requirements. There are therefore injectors with electromagnetic controllable injection valves are known in which the fuel is injected at constant pressure and the fuel quantity is dosed by electrical means by changing the valve opening time.

The present invention seeks a reduction in price and a similar

increased operational reliability of such a device, and provides for metering by means of variable injection pressure The valve opening time remains constant. Mach the invention is to provide a pressure relief valve for pressure control of the upstream Fuel can be controlled by the throttle valve adjustment.

On the basis of an exemplary embodiment, the invention is to be explained below with reference to the attached figure.

The fuel is sucked from the bar 1 through a filter 2 of an eccentric pump 3 and pumped with a variable corresponding to the engine conditions pressure of 2-15 a ^ ü ⁱⁿ d-ie leads 4 to the injectors. 5 The variable pressure is in

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Range from 2 - -12 atmospheres regulated by an adjustable pressure relief valve 6. An eccentric '], which - as indicated by the dotted line - is firmly connected to the throttle valve 9:', is, when the throttle valve 9 is closed, your pressure relief valve C is the smallest and when the throttle valve 9 is open, the greatest bias. The pressure is 2 atmospheres when idling and 12 atmospheres at maximum speed. To further increase the pressure during the acceleration side of the vehicle, a solenoid shut-off valve IC is provided which can be closed by a contact switch 12 which is closed when the accelerator pedal 11 is in the full throttle position. In this case, the flow resistance in the return line 13, 13'i is increased. The pressure rises to 15 atm and is kept there by the pressure relief valve 14. The electrical control of the solenoid shut-off valve 10 will be described further below.

Throttle valve 9 ″ ^{on (} i eccentric 7 are actuated by gas pedal 11. A pulse generator 15 for the electronic control of the injection valves 5 is located in the ignition distributor 16 and runs at half the engine speed. The eccentric pump 3 delivers four times the amount of fuel required.

The pulse generator 15 consists of one in the right, upper, part of the Figure separately shown slip ring body 17 with a trapezoidal Impulse cam 17a. The pulse cam 17a has an upper width that a current pulse of 2 msec at the idling speed to the corresponding injection valve 5 there. With increasing speed A centrifugal device 18 lifts up to 3u maximum speed the slip ring body I7 in such a way that the pulse cam 17a respectively has the effective width corresponding to the pulse side of 2 msec. At an idle speed of 1000 rpm, and one Full load speed of 5000 rpm, must therefore be the lower I-cam width 5 times wider than the upper I-cam width.

The power supply from the battery 20 to the injection valves 5 takes place whenever the sliding contact 21 (which is constantly 'on the * conductive ring 17b grinds) over the pulse cam 17a the sliding contact 22 is connected. The - seen in the direction of rotation - The front edge of the impulse cam 17a is inclined, while the rear edge is perpendicular. In this way

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BATH ORIGINAL

becomes - with the same injection duration - the opening phase of the injection valves 5, brought forward in time, as is operationally desired.

The power supply for the solenoid valve 10 is also via the slip ring body 17 out. At low engine speeds and fully depressed accelerator, the contact piece 19 grinds on the Stroa-conducting part 17b of slip ring 17. At higher speeds the slip ring body 17 is raised and the flow of current is interrupted, since the contact piece 19 now grinds on the lower currentless part 17c of the slip ring body 17. The injection pressure can then only be a maximum of 12 atm "

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Claims (4)

Expectations 1. Injector for gasoline engines with by electric Impulse controllable, in the intake manifold arranged injection valves, which the fuel with variable pressure is upstream, characterized in that a pressure relief valve (6) for pressure control of the upstream fuel can be controlled by the throttle valve adjustment. 2. Apparatus according to claim 1, characterized in that Constant opening impulses generated by means of a contact arrangement (1?) driven by the distributor at which the effective contact path (17 &) through a centrifugal force direction (ΙΟ) inversely proportional to the Dr eh ζ aiii is changed. 3. Apparatus according to claim 2, characterized by a slip ring body (17) which can be raised by centrifugal force a trapezoidal pulse cam (l7a), whose - in the direction of rotation against - front edge sloping and its rear edge perpendicular to the contact tooth. 4. Apparatus according to claim 1, characterized by a solenoid valve serving for injection pressure increase (lO), the by one controlled when the accelerator pedal (ll) is depressed Switch (12) and a speed-dependent contact device (17, IQ) can be controlled. 009832/0796 BATH ORIGINAL