Temperature responsive open/closed loop switching for lambda control

• US 4,392,470 A
• Filed: 06/24/1981
• Issued: 07/12/1983
• Est. Priority Date: 06/28/1980
• Status: Expired due to Term

• Current Assignee: Robert Bosch GmbH
• Original Assignee: Robert Bosch GmbH
• Inventors: Horbelt, Michael, Gunther, Dieter, Arnold, Herbert, Bertsch, Richard, Schnurle, Hans, Bottcher, Siegfried
• Primary Examiner(s): Nelli, Raymond A.
• Application Number:
  US06/276,757
• Time in Patent Office: 748 Days
• Field of Search: 123/440, 60/276, 60/285
• US Class Current: 123/676
• CPC Class Codes: F02D 41/1488 Inhibiting the regulation

Abstract

A regulating device is described for regulating or adjusting the composition of the operating mixture of an internal combustion engine. When the engine or exhaust gas probe is still cold, the composition of the fuel-air mixture is controlled in an open-loop manner, and upon the attainment of a minimum operating temperature, the closed-loop regulating device for influencing the fuel-air mixture is activated. The activation of the regulating device is effected, when the engine is being operated under a load, after the attainment of a first, low temperature value; during engine idling, this is effected after the attainment of a second, higher temperature value. Via the throttle valve, a switchover is effected between two threshold values of a threshold switch.

Claims

1. A lambda regulating device for the composition of the operating mixture being combusted in an internal combustion engine comprising, an exhaust gas probe producing an output signal and being applied to said lambda regulating device for correcting the operating mixture composition, a means supplying a temperature signal a means for deactivating and activating said lambda regulating device in accordance with the evaluation of said temperature signal, a threshold switch having two inputs connected to said lambda regulating device, one of said inputs being responsive to said temperature signal, a threshold value generating means responsive to said threshold switch, and a switchover means controllable in accordance with a position of a throttle valve of said engine for switching said threshold switch between a low and a high value with respect to said temperature signal, said switchover means being reversible up to the point where the higher value has been attained.

2. A regulating device as defined by claim 1, wherein in the idling position of the throttle valve, a first switching input takes effect, and in the remaining operational range a second switching input takes effect.

3. A regulating device as defined by claim 2, wherein said throttle valve in the idling position, actuates said switchover means, whereby one of said inputs of said threshold switch is capable of being additionally connected with a predetermined voltage potential.