Method and apparatus for optimized gear shifting indication

A gear shifting operation indication apparatus comprising:

• an engine rotation sensor for detecting current engine speed;
• a speed meter for detecting actual speed of a car;
• an air flow meter for detecting an intake arir flow;
• control unit means, responsive to said sensor and said meters, for determining shifting operation indications;
• an indicator, responsive to said control unit means, for indicating either shift-up or shift-down operation based on said control means determinations;
• said control unit means comprising means for
• calculating current engine load Q/N from the intake air flow Q and the engine speed N,
• comparing said current engine load thus calculated with a predetermined engine load constant,
• recalculating said current engine load if said comparison finds said current engine load less than or equal to said predetermined constant,
• calculating current shift position from current engine speed N, current vehicle speed V and the known transmission gear ratio,
• determining a first engine load operation function Y=f (N) and a second operating engine load function .beta.=g (N) from known equal fuel consumption rate curves,
• compring said first operating load operation function Y with said current engine load Q/N,
• indicating a shift-down operation to be performed if said first function has a value greater than said current engine load Q/N,
• performing additional functions for indicating subsequent shift-up operation if said first function has a value less than or equal to said current engine load Q/N,
• calculating current engine horsepower PS from said current engine speed N and current engine load Q/N, and
• calculating expected engine speed N' necessary for maintaining said current car speed V if there is a one shift-up operation performed on said transmission.

A method for indicating gear shifting operation for a vehicle transmission, comprising the steps of;

• calculating current engine load Q/N from the intake air flow Q and the engine speed N;
• comparing said current engine load thus calculated with a predetermined engine load constant;
• re-starting at the first step of the method if said comparison finds said current engine load less than or equal to said predetermined constant;
• calculating current shift position from current engine speed N, current vehicle speed V and the known transmission gear ratio;
• determining a first engine load operation function Y=f (N) and a second operating engine load function .beta.=g (N) from known equal fuel consumption rate curves;
• comparing said first operating load operation function Y with said current engine load Q/N;
• indicating a shift-down operation to be performed if said first function has a value greater than said current engine load Q/N;
• performing additional steps for potential shift-up operation indication if said first function has a value less than or equal to said current engine load Q/N;
• establishing a data map based on said current engine speed N and current engine load Q/N;
• dividing said map into roughly four quadrants by said first and second engine load operation functions;
• indicating a shift-up operation when said calculated engine load is in a lower right-hand quadrant;
• indicating a shift-down operation when said calculated engine load is in either of the left-hand quadrants;
• and
• indicating no shifting operations when said engine load is in the upper right-hand quadrant of said data map.

A gear shifting operation indication apparatus comprising:

• an engine rotation sensor for detecting current engine speed;
• a speed meter for detecting actual speed of a car;
• an air flow meter for detecting an intake air flow;
• control unit means, responsive to said sensor and sait meters, for determining shifting operation indications;
• an indicator, responsive to said control unit means, for indicating either shift-up or shift-down operation based on said control means determinations;
• and
• said control unit means including means for calculating current engine load Q/N from the intake air flow Q and the engine speed N,
• comparing said current engine load thus calculated with a predetermined engine load constant,
• recalculating said current engine load if said comparison finds said current engine load less than or equal to said predetermined constant,
• calculating current shift position from current engine speed N, current vehicle speed V and the known transmission gear ratio,
• determining a first engine load operation function Y=f (N) and a second operating engine load function .beta.=g (N) from known equal fuel consumption rate curves,
• comparing said first operating load operation function Y with said current engine load Q/N,
• indicating a shift-down operation to be performed if said first function has a value greater than said current engine load Q/N,
• performing additional functions for indicating subsequent shift-up operation if said first function has a value less than or equal to said current engine load Q/N,
• establishing a data map based on said current engine speed N and current engine load Q/N,
• dividing said map into roughly four quadrants by said first engine load operation function Y and said second engine load operation function .beta..
• indicating a shift-up operation when said calculated engine load is in a lower right-hand quadrant,
• indicating a shift-down operation when said calculated engine load is in either of the left-hand quadrants, and
• indicating no shifting operations when said engine load is in the upper right-hand quadrant of said data map.

Method for indicating optimum gear shift operation for minimizing fuel consumption in a vehicle having a manual transmission, detecting means for detecting various engine parameters, a microprocessor including a read-only memory, a random-access memory, and a central processing unit for maintaining constant vehicle speed and constant engine power responsive to signals from said detecting means and for outputting an indicating signal indicative of the optimum gear shift operation, and indicating means responsive to said indicating signal for indicating said gear shift operation, said method comprising the steps of:

• (a) storing isometric curved lines that represent curves of equal fuel-consumption as defined on a load/speed diagram, and separating said map into three areas by two curves, one curve represented by Y=f (N) and crossing the points representing the minimum fuel consumption rate of each of said isometric curved lines and the other curve represented by .beta.=g (N), for determining whether engine load is defined as high, wherein said three areas defined on said map comprise:
• a first area (I) in which the value Y corresponds to a currently detected engine speed which is less than the current engine load;
• a second area (II) in which the value of Y corresponds to the detected engine speed being more than the value of the current engine load with the value corresponding to the detected engine speed being more than the current engine load;
• and
• a third area (III) in which the value of Y corresponding to the detected engine speed is more than the value of engine load with the value corresponding to currently detected engine load being less than the current engine load;
• (b) outputting a signal from said microprocessor to said indicating means to cause said indicating means to output a signal indicative of one-step downshifting, whenever the detected point determined by a combination of said detected engine speed and said engine load is in said first area;
• (c) indicating no gear changing operation if said detected point is in said second area;
• and
• (d) outputting a signal from said microprocessor to said indicating means to cause said indicating means to output a signal indicative of one-step upshifting, whenever said detected point determined by said combination of said detected engine speed and engine load is in said third area.