Vehicle speed control system with dual interrupt safety circuit
First Claim
1. Vehicle speed control system to control a fuel supply element (42) of an internal combustion (IC) engine driving the motor vehicle comprisingmeans (10) providing an actual speed signal;
- means (14) providing a command speed signal;
comparator means (16) connected to said actual and said command speed signal providing means and providing a speed error signal;
an automatically controllable positioning element (40) controlling the position of the fuel supply element (42) of the engine;
a control stage (20) and a power stage (30) connected to and controlled by the comparator means (16) and providing output energization for automatic control of the positioning element (40);
a selectively engageable coupling (41) interposed between the positioning element (40) and the fuel supply element (42);
electromagnetic control means (46) controlling, in response to an "engage" and a "disable" signal, respectively, selective engagement and disengagement of the coupling (41) to thereby engage or disable control of the fuel supply element position as a function of speed error signals, andmeans (50, 55,
56) applying the "disable" signal as an overriding speed control signal to the automatically controllable positioning element to command operation of the positioning element (40) in a direction to move the fuel supply element to idle speed fuel supply position.
0 Assignments
0 Petitions
Accused Products
Abstract
A motor drives a fuel supply control element, typically the throttle of an automotive-type gasoline engine through a solenoid controlled coupling. Upon brake, clutch, manual switch, or other interrupting operation, the solenoid is de-energized so that a spring can permit interruption of the coupling and a throttle return spring can return the throttle to idle position. To prevent dangerous conditions from arising, and run-away of the engine in case of malfunction of the coupling, an electronic circuit is provided to introduce a signal to the speed control system which tends to move the throttle positioning motor to change the position of the throttle to idle speed condition if a disabling signal is sensed. Preferably, additionally, a first timing circuit interrupts energization of the positioning motor servo loop after a predetermined period of time; a second timing circuit may be provided which has a time constant which is long with respect to the return time of the throttle under its spring connection and controlling a malfunction memory which provides a visual indication of malfunction in the system.
-
Citations
12 Claims
-
1. Vehicle speed control system to control a fuel supply element (42) of an internal combustion (IC) engine driving the motor vehicle comprising
means (10) providing an actual speed signal; -
means (14) providing a command speed signal; comparator means (16) connected to said actual and said command speed signal providing means and providing a speed error signal; an automatically controllable positioning element (40) controlling the position of the fuel supply element (42) of the engine; a control stage (20) and a power stage (30) connected to and controlled by the comparator means (16) and providing output energization for automatic control of the positioning element (40); a selectively engageable coupling (41) interposed between the positioning element (40) and the fuel supply element (42); electromagnetic control means (46) controlling, in response to an "engage" and a "disable" signal, respectively, selective engagement and disengagement of the coupling (41) to thereby engage or disable control of the fuel supply element position as a function of speed error signals, and means (50, 55,
56) applying the "disable" signal as an overriding speed control signal to the automatically controllable positioning element to command operation of the positioning element (40) in a direction to move the fuel supply element to idle speed fuel supply position. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12)
-
Specification