DE1576476A1 - Control and monitoring device for an internal combustion engine - Google Patents

Description

R. 8950
2.8.1967 Lr / Sz

Attachment to
Patent- »a4
-

KOBE R T B OS CH GHBH, Stuttgart V, Breitscheidstrasse 4 Control and monitoring device for an internal combustion engine

The invention relates to a control and monitoring device for an internal combustion engine working with mixture compression, the a throttle valve arranged in its intake duct with a die Has the closed position of the throttle valve limiting stop, in particular to a control unit for an internal combustion engine equipped with an electrically controlled gasoline injection system.

To reduce fuel consumption and make emissions more harmful Reduce exhaust gas components when the internal combustion engine when the throttle valve is closed by the inertia forces of the vehicle at speeds significantly above idle speed is driven and runs in overrun mode, the fuel supply to the internal combustion engine is appropriately shut off. These Fuel shut-off takes place with the help of the aforementioned control

009820/0664 - 2 -

Robert Bosch GmbH 'R. 8950 Lr / Sz

Stuttgart

and monitoring device to which the invention relates. This device can either be installed in the intake manifold of the internal combustion engine prevailing negative pressure or by one with the throttle valve coupled switch can be controlled. In the latter In addition, there is a case of the speed of the internal combustion engine or the vehicle speed dependent switch, which the fuel cut off at low speeds or low vehicle speeds so that the The internal combustion engine continues to idle below these limit values can. The control by a throttle switch and an additional, speed-dependent switch is more complex ^ however, results in a significantly greater reduction in the harmful exhaust gas components in the overrun mode of the internal combustion engine than in a control that is carried out exclusively by a switch that is dependent on the negative pressure in the intake manifold of the internal combustion engine.

In the experiments preceding the invention, it was used as a throttle valve switch a microswitch has already been used, which is rotatably mounted to the shaft of the throttle valve connected lever arm is operated. Such a commercially available microswitch, however, has a snap-action behavior, which therein shows that the switch during the closing movement of the throttle valve closed about 3 to 5 ° before the idle division, however is only opened again when- the throttle valve is 5 to 8 ° has opened beyond the idle position. The one between the The switch-on position and the angle of rotation lying around the switch-off position are referred to below as switching hysteresis. This should if possible be small. In addition, it is desirable that the contacts of the switch are already at a very small opening angle of the throttle valve be brought into their open position. If the contacts only at a throttle valve opening angle of 5 to 8 ° in their open position are brought and thereby the fuel shut-off cancel, -so this results in a very hard onset of the torque.

- 3 -, 009820/0664

Robert Bosch GmbH R. 8950 Lr / Sz

Stuttgart

The invention is based on the objects, taking advantage of the above According to the test results described, a control and monitoring device that becomes effective depending on the respective throttle valve position to create that responds even at very small opening angles of the throttle valve and the smallest possible sehalt hysteresis Has. In addition, it should be easily adjustable and offer the possibility of jerk-free idling of the internal combustion engine required, in the idle position of the throttle valve to make the passage cross-section kept free. According to the invention is provided for this purpose that the closed position of the Throttle valve limiting stop as an electrical, a fixed one Contact and a movable mating contact comprehensive switch is formed and that with the throttle valve shaft Lever is connected, in the pivoting range of which the two contacts are located.

Further details and appropriate further developments arise from that shown in the drawing, described below Embodiment.

The intake manifold 1, shown partially in section, of an internal combustion engine, not shown otherwise, contains a throttle valve 2, which is firmly connected to its throttle valve shaft 3. The throttle valve shaft, which is rotatably mounted in the intake manifold Ϊ, is off at its end the suction pipe projecting end connected to a lever 4, which at its end eirr ~ insulating piece 5 carries. There is a holder on the suction pipe 1 6 attached. On this sit against each other and against the holder 6 insulates a contact carrier 7 with a stationary contact and a contact spring 9 which carries a movable contact 10.

If that is not shown in the drawing, with the. throttle coupled accelerator pedal is not actuated, a return spring, also not shown in the drawing, attempts the throttle valve shaft turn counterclockwise while pivoting the throttle valve into its closed position. Here

003820/0664 "*"

Robert Bosch GmbH R. 8950 Lr / Sz

Stuttgart

the contacts 8 and 10 pressed on each other and thereby the switch closed. In addition, the contact carrier 7 acts as an idle stop for the throttle valve and ensures that the internal combustion engine runs smoothly Gap between the throttle valve edge and the inner wall of the intake pipe. This gap can be used for idling the internal combustion engine sufficient amount of idle air in the internal combustion engine reach. To set this amount of idle air, the holder 6 Elongated holes are provided that allow the holder 6 with respect to the To move suction pipe 1.

Through the combination of the throttle valve stop and idle contact two main advantages are achieved: On the one hand, the switching contacts open after a very small opening movement of the Throttle valve out of the idle division and on the other hand can the idle speed can easily be readjusted by moving the holder 6, which serves as a throttle valve stop, to the side, without a change in the throttle valve angle which is decisive for the opening or closing movement of the switching contacts compared to the idle position. With the one that has been common since then A microswitch had to be used to avoid this disadvantage that occurs when changing the idle speed provide a laterally bypassing the closed position of the throttle valve for the idle air, which in its effective cross-section could be changed by a regulating screw. Due to the inventive arrangement of one at the same time as a throttle valve stop effective contact carrier arrangement therefore also results in a much simpler structural design of the Throttle valve zone of the intake pipe.

The adjustability of the contact carrier 7, which simultaneously acts as a throttle valve stop, can also be achieved in such a way that that an eccentric screw known as an adjusting device in ignition interrupters is provided. It is also conceivable that the Replace contact carrier 7 and contact 8 with a screw

009820/0664 " ⁵ "

Kobert Bosch. GmbH R. 8950 Lr / Sz

Stuttgart

and to arrange the screw with its longitudinal axis so that its head faces the contact spring 9 and its shaft is at least approximately runs in a plane that intersects the intake pipe axis perpendicularly.

009820/0664

Claims (3)

Robert Bosch GmbH R. 8950 Lr / Sz '.; ■ Stuttgart. . Expectations 1. Control and monitoring device for a mixture compression working internal combustion engine, the one in its intake duct arranged throttle valve with a stop limiting the closed position of the throttle valve, in particular on a Control unit for an internal combustion engine of a motor vehicle equipped with an electrically controlled gasoline injection system, characterized in that the stop as an electrical, a fixed contact (8) and a movable one Counter-contact (.10) comprising switch is formed and that a lever (4) is connected to the throttle valve shaft (3), the two contacts are in the pivoting range. 2. Apparatus according to claim 1, characterized in that the fixed contact (8) on a contact carrier serving as a stop (7) sits, which is adjustable to adjust the idling of the internal combustion engine in the pivoting range of the lever (4). 3. Apparatus according to claim 1 or 2, characterized in that the Movable switching contact (10) is seated on a leaf spring (9) and in the pivoting range of the lever (4 ·) between this and the stationary one Contact (8) is arranged. - 2 00982070664 Robert Bosch GmbH ^T R. 8950 Lr / Sz Stuttgart M-, device after. Claim 3, characterized in that the leaf spring ^ '(9) together with the carrier (?) For setting the idle air. Gap is adjustable. Yy. Device according to claim 1 or 2, characterized in that the fixed contact (8) connected to the shaft of a screw is, whose longitudinal axis is approximately parallel to the pivot plane of the lever (4 ·) and at least approximately at right angles to that through its screwing in place runs in a carrier and through the axis of rotation of the throttle valve shaft (3) going connecting line. 009820/0664 L e τ s e i t