Engine control
AssigneeCaterpillar Tractor Co.
InventorsJoe E. Fuzzell, Paul E. Turnquist
Life of this patent
Estimating the term…
Abstract
An engine control wherein a shaft driven by the engine causes a first signal to be generated and then a second signal after the shaft has rotated through a predetermined degree. The first signal starts a timer into operation, the timer producing a timer pulse of predetermined duration. Time coincidence of the timer signal and second signal indicates that a critical engine speed has been reached and such time coincidence is used to effect a control function. If the shaft rotates in the opposite direction the sequence of generation of the first and second signals in such direction is detected and used to generate a reverse-direction signal which is used to effect a control function. An automatic impedance-changing circuit enables the control to be used with a wide range of batteries.
Claims43
Apparatus for controlling the functioning of an engine comprising:
- a shaft driven by said engine at a speed proportional to the engine speed,
- means responsive to rotation of said shaft through a predetermined degree of rotational movement for generating a first signal at the beginning of such movement and a second signal at the end of such movement,
- timer means for producing a timer signal of predetermined time duration,
- means for starting said timer in response to generation of said first signal,
- means for effecting a control function in response to time coincidence of said second signal and said timer signal.
Control apparatus comprising:
- a housing,
- a shaft mounted in said housing for rotation about the axis of said shaft,
- a magnet mounted on said shaft for movement by said shaft through an orbital path relative to said housing,
- magnetically actuated sensor means mounted on said housing adjacent said orbital path for generating a first signal when said magnet has been moved to a fixed point in its orbital path and a second signal when said magnet has been moved a predetermined distance from said fixed point,
- timer means for producing a signal of predetermined time duration,
- means for starting said timer means into operation in response to generation of said first signal,
- means for effecting a control function in response to time coincidence of said second signal and said timer signal.
Apparatus of the character described, comprising:
- a housing,
- a shaft mounted in said housing for rotation about the axis of said shaft,
- a magnet mounted on said shaft for movement thereby through an orbital path relative to said housing,
- first and second magnetically actuated sensors mounted on said housing and disposed adjacent said orbital path, said sensors and magnet being dimensioned and said sensors being disposed relative to each other such that as said magnet is moved past said sensors said magnet will first actuate one of said sensors alone, then actuate both sensors simultaneously, then actuate the other of said sensors alone.
An automatic impedance-changing circuit for connecting a load to a direct current voltage source, said circuit having an input connected to one side of said voltage source and an output connected to said load, said load being also connected to the other side of said voltage source for current flow from a voltage source through said circuit and said load, said current comprising:
- a first current path from the input of said circuit to the output thereof, said first current path having a resistor therein,
- a second current path from the input of said circuit to the output thereof, said second current path having a switch means therein for allowing current flow through said second current path when said switch means is closed and for preventing current flow through said second current path when said switch means is open,
- means connected between the input of said circuit and said other side of said voltage source for closing said switch means if the voltage at said input is below a predetermined magnitude.
An automatic impedance-changing circuit for connecting a load to a direct current voltage source, said circuit having an input connected to one side of said voltage source and an output connected to said load, said load also being connected to the other side of said voltage source for current flow from a voltage source through said circuit and said load, said circuit comprising:
- a first current path from the input of said circuit to the output thereof, said first current path having a resistor therein,
- a second current path from the input of said circuit to the output thereof, said second current path having a transistor therein to allow or prevent current flow through said second current path if said transistor is on or off, respectively,
- means including a zener diode connected between the input of said circuit and said other side of said battery, said Zener diode being conductive if the voltage at said input exceeds the breakdown potential of said zener diode,
- means responsive to conduction of said zener diode for turning said transistor off and responsive to non-conduction of said zener diode for turning said transistor on.
Dependencies are inferred from the claim text.