Engine test and display apparatus

Improved apparatus for measuring the timing of a chamber of an internal combustion engine having a predetermined number of chambers and including an ignition system having fuel ignitors, said ignition system comprising a switch periodically opened and closed in synchronism with the rotation of the engine in order to create time-spaced ignition pulses for firing the ignitors, the time duration between successive closures of the switch defining a chamber timing period, said apparatus comprising:

• clock means for producing clock pulses at a predetermined rate;
• first counter means for counting the clock pulses;
• second counter means for counting the clock pulses;
• first gate means for transmitting clock pulses to the first counter means in response to a first one of the ignition pulses and for preventing the transmission of clock pulses to the first counter means in response to a second one of the ignition pulses;
• second gate means for transmitting clock pulses to the second counter means only during one or more selected chamber timing periods which occur between the first ignition pulse and the second ignition pulse;
• means for modifying the one or more selected chamber timing periods during which clock pulses are transmitted to the second counter means;
• processor means for producing a digital chamber timing signal having a value proportional to the count of the second counter means divided by the count of the first counter means;
• and
• display means for displaying a chamber timing number having a value proportional to the value of the chamber timing signal, whereby the chamber timing number displayed on the display means is associated with one or more preselected chambers and ignitors.

Apparatus for analyzing an internal combustion engine comprising:

• means coupled to the engine for generating a digital measurement signal corresponding to a predetermined engine condition;
• display means having a face for displaying at a first location on the face a first character group of alphabetic letters indicative of the unit in which the predetermined engine condition is measured and for displaying at a second location on the face a first number indicative of the value of the engine condition being measured;
• memory means for storing a first character code signal corresponding to the first character group, a first display address signal corresponding to the first location, and a second display address signal corresponding to the second location;
• display controller means for enabling the display means to display the first character group at the first location in response to the first character code signal and the first display address signal and for enabling the display means to display the first number at the second location in response to the second display address signal and a first digital display signal corresponding to the value of said engine condition in the units indicated by the first character group;
• and
• processor means for altering the value of the digital measurement signal to produce the first digital display signal, transmitting the first digital display signal and second display address signal to the display controller means and for transmitting the first character code signal and first display address signal to the display controller means, at least said first digital display signal being produced and transmitted to the display controller means in less than 8 seconds from the time the engine condition occurs, whereby the units and value of the engine condition are displayed in digital form on the face of the display means in real time, so that an operator of the apparatus can determine the value of the engine condition as the engine is operating.

Apparatus for analyzing an internal combustion engine comprising:

• means coupled to the engine for generating a digital measurement signal corresponding to a predetermined engine condition;
• display means having a face for displaying at a first location on the face a first character group of alphabetic letters indicative of the unit in which the predetermined engine condition is measured, for displaying at a second location on the face a first number indicative of the value of the engine condition being measured at a first point in time, and for displaying at a third location on the face a second number indicative of the value of the engine condition being measured at a second point in time;
• memory means for storing a first character code signal corresponding to the first character group, a first display address signal corresponding to the first location, a second display address signal corresponding to the second location, and a third display address signal corresponding to the third location;
• display controller means for enabling the display means to display the first character group at the first location in response to the first character code signal and the first display address signal, for enabling the display means to display the first number at the second location in response to the second display address signal and a first digital display signal corresponding to the value of said engine condition in the units indicated by the first character group at the first point in time, and for enabling the display means to display the second number at the third location in response to the third display address signal and a second digital display signal corresponding to the value of said engine condition in the units indicated by the first character group at the second point in time;
• processor means for transmitting the first character code signal and first display address signal to the display controller means, operative in a first mode at the first point in time for altering the value of the digital measurement signal to produce the first digital display signal and for transmitting the first digital display signal and second display address signal to the display controller means, and operative in a second mode at the second point in time for altering the value of the digital measurement signal to produce the second digital display signal and for transmitting the second digital display signal and third display address signal to the display controller means;
• and
• selection means for operating the processor means in the first mode whereby the first number is displayed on the face of the display means so that the value of the engine condition at the first point in time can be observed, and for operating the processor means in the second mode whereby the second number is displayed on the face of the display means so that the value of the engine condition at the second point in time can be observed.

Apparatus for automatically analyzing an internal combustion engine during a first operating state and a second operating state comprising:

• means coupled to the engine for generating first and second digital measurement signals corresponding to first and second engine conditions, respectively, which are useful for analyzing the first operating state and for generating third and fourth digital measurement signals corresponding to third and fourth engine conditions, respectively, which are useful for analyzing the second operating state;
• display means having a face for displaying simultaneously during a first time period first and second numbers corresponding to the first and second digital measurement signals, respectively, a first character group of alphabetical letters indicative of the units of the first number and a second character group of alphabetical letters indicative of the units of the second number, and for displaying simultaneously during a second time period, third and fourth numbers corresponding to the third and fourth digital measurement signals, respectively, a third character group of alphabetical letters indicative of the units of the third number and a fourth character group of alphabetical letters indicative of the units of the fourth number;
• memory means for storing first character code signals corresponding to the first character group, second character code signals corresponding to the second character group, third character code signals corresponding to the third character group and fourth character code signals corresponding to the fourth character code group;
• display controller means for enabling the display means to display the first character code group in response to the first character code signals, to display the second character code group in response to the second character code signals, to display the third character code group in response to the third character code signals, to display the fourth chacter code group in response to the fourth character code signals, to display the first number in response to a first digital display signal corresponding to the value of the first engine condition in the units indicated by the first character code group, to display the second number in response to a second digital display signal corresponding to the value of the second engine condition in the units indicated by the second character group, to display the third number in response to a third digital display signal corresponding to the value of the third engine condition in the units indicated by the third character group, and to display the fourth number in response to a fourth digital display signal corresponding to the value of the fourth engine condition in the units indicated by the fourth character group;
• processor means for operating in a first mode during the first time period to alter the digital measurement signals to produce the first and second digital display signals, respectively, and to transmit the first and second digital display signals and the first and second character code signals to the display controller means so that the first and second numbers and the first and second character groups are displayed, and for operating in a second mode during the second time period to alter the value of the third and fourth digital measurement signals to produce the third and fourth digital display signals, respectively, and to transmit the third and fourth digital display signals and the third and fourth character control signals to the display controller means so that the third and fourth numbers and the third and fourth character groups are displayed;
• and
• selection means for enabling the processor means to operate in the first mode so that the first operating state of the engine can be analyzed by observing the first and second numbers on the face of the display means and for enabling the processor means to operate in the second mode so that the second operating state of the engine can be analyzed by observing the third and fourth numbers on the face of the display means.

Apparatus for displaying a first engine condition associated with a first chamber of an internal combustion engine and for separately displaying a second engine condition associated with a second chamber of the internal combustion engine, said apparatus comprising:

• means coupled to the engine for generating a first digital measurement signal corresponding to the first engine condition and for generating a second digital measurement signal corresponding to the second engine condition;
• display means having a face for displaying at a first location on the face a first character group indicative of the unit in which the first and second engine conditions are measured, for displaying at a second location on the face a first number indicative of the value of the first engine condition and for displaying at a third location on the face a second number indicative of the value of the second engine condition;
• memory means for storing first character code signals corresponding to the first character group, a first display address signal corresponding to the first location, a second display address signal corresponding to the second location and a third display address signal corresponding to the third location;
• display controller means for enabling the display means to display the first character group at the first location in response to the first character code signals and the first display address signal, for enabling the display means to display the first number at the second location in response to the second display address signal and a first digital display signal corresponding to the value of said first engine condition in the units indicated by the first character group, for enabling the first display means to display the second number at the third location in response to the third display address signal and a second digital display signal corresponding to the value of said second engine condition in the units indicated by the first character group;
• and
• processor means for transmitting the first character code signals and first display address signal to the display controller means so that the first character group is displayed, for altering the value of the first and second digital measurement signals to produce the first and second digital display signals and transmitting the first and second digital display signals together with the second and third display address signals to the display controller means, whereby the first number and second number are simultaneously displayed on the face of the display means so that the value of the first and second engine conditions can be observed.

Apparatus for determining and displaying the value of a predetermined parameter of an internal combustion engine having a plurality of chambers fitted with ignitors operated by a series of time-spaced firing signals, said apparatus comprising:

• means coupled to the engine for generating a digital measurement signal proportional to the value of the predetermined parameter;
• display means having a face for displaying at a first location a scale of numbers indicative of the predetermined parameter and for displaying a variable graphic image adjacent the scale;
• memory means for storing first character code signals corresponding to the scale of numbers and first number display address signals corresponding to the first location;
• display controller means for enabling the display means to display the scale of numbers at the first location in response to the first character code signals and the first number display address signals, and for producing a graphic image at a position adjacent the scale of numbers determined by the value of a digital display signal, so that the predetermined parameter is visually represented;
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• processor means for transmitting the first character code signals and first number display address signals to the display controller means so that the scale of numbers is displayed and for converting the digital measurement signal into a digital display signal and transmitting the digital signal to the display controller means so that the graphic image is displayed on the display means.

Apparatus for measuring and displaying a parameter useful for diagnosing an internal combustion engine comprising:

• transducer means for generating a digital calibration signal corresponding to the ambient value of the parameter adjacent the engine during a first time period and for generating a digital measurement signal corresponding to the value of the parameter produced by the engine as well as the ambient value of the parameter during a second time period;
• display means including a face for displaying a digital measurement number indicative of the value of the parameter produced only by the engine;
• memory means for storing the digital calibration signal;
• processor means for combining the digital calibration signal and the digital measurement signal to produce a digital calculated signal having a value which eliminates the effect of the ambient value of the parameter on the digital measurement signal;
• and
• display controller means for enabling the display means to display the digital measurement number in response to the digital calculated signal.

Apparatus for measuring and displaying a parameter useful for diagnosing an internal combustion engine comprising:

• transducer means coupled to the engine for generating a digital measurement signal corresponding to the value of the parameter produced by the engine;
• display means including a face for displaying a digital measurement number indicative of the value of the parameter produced by the engine if the digital measurement number is within a predetermined range of values and for displaying a symbol if the digital measurement signal is outside the predetermined range of values;
• memory means for storing range signals indicative of the range of values of the digital measurement number acceptable for display on the display means;
• processor means for comparing the digital measurement signal with the range signals, for producing the error signal if the value of the digital measurement signal is outside the predetermined range of values indicated by the range signals, and for producing a digital display signal corresponding to the value of the digital measurement signal is within the predetermined range of values indicated by the range signals;
• and
• display controller means for enabling the display means to display the digital measurement number in response to the digital display signal and for enabling the display means to display the symbol in response to the error signal.

Apparatus for automatically determining the relative power produced by at least the first and second chambers of an internal combustion engine, the first and second chambers being fitted with first and second ignitors fired by time-spaced firing signals generated by the engine, said apparatus comprising:

• disabling means for preventing a firing signal from being transmitted to the first ignitor in response to a first disable signal and for preventing a firing signal from being transmitted to the second ignitor in response to a second disable signal;
• speed detection means for generating a digital base speed signal having a value proportional to the base speed of the engine when the first or second ignitors are enabled to receive firing signals, for generating a first digital disabled speed signal proportional to the first disabled speed of the engine when the first ignitor is prevented from receiving firing signals and for generating a second digital disabled speed signal having a value proportional to the second disabled speed of the engine when the second ignitor is prevented from receiving firing signals;
• memory means for storing the digital base speed signal in response to a store signal;
• display means for displaying a first speed change number indicating the difference between the speed of the engine when both first and second ignitors are enabled and when the first ignitor is prevented from receiving firing signals and for displaying a second speed change number indicating the difference between the speed of the engine when both first and second ignitors are enabled and when the second ignitor is prevented from receiving firing signals;
• display controller means for enabling the display means to display the first speed change number in response to a first speed change signal and for enabling the display means to display the second speed change number in response to a second speed change signal;
• and
• processor means for enabling the production of the first disabled speed signal at a first point in time and for calculating the first speed change number in response to the digital base speed signal and the first disabled speed signal, whereby the first speed change number is displayed, and
• for enabling the production of the second disabled speed signal at a second point in time and for calculating the second speed change number in response to the digital base speed signal and the second disabled speed signal, whereby the second speed change number is displayed.

Apparatus for measuring and displaying a parameter of an internal combustion engine which is capable of varying over a first and second range of values, said apparatus comprising:

• analog measuring means operable with a first degree of sensitivity for generating a first analog measuring signal having a first value proportional to the parameter and operable with a second degree of sensitivity for generating a second analog measuring signal having a value proportional to the parameter times a scale factor;
• converter means for converting the first analog measuring signal to a first digital measurement signal and for converting the second analog measuring signal to a second digital measurement signal;
• display means having a face for displaying at a first location on the face a first character group indicative of the units in which the parameter is measured and for displaying at a second location on the face a first number indicative of the value of the parameter in the first range and a second number indicative of the value of the parameter in the second range;
• display controller means for enabling the display means to display the first number at the second location in response to a first digital display signal and to display the second number at the second location in response to a second digital display signal;
• memory means for storing a scale factor signal corresponding to the scale factor;
• and
• processor means for operating the analog measuring means with the first degree of sensitivity when the parameter is within the first range of values so that the first digital measurement signal is produced and for converting the first digital measurement signal into the first conversion signal to form the first digital display signal whereby the first number is displayed, and for operating the analog measuring means with the second degree of sensitivity when the parameter is within the second range of values so that the second digital measurement signal is produced and for combining the second digital measurement signal with the scale factor signal to form the second digital display signal whereby the second number is displayed.

Apparatus for measuring and displaying the maximum value of a parameter of an internal combustion engine which varies in value comprising in combination:

• means for generating during a predetermined time period a series of time-spaced digital measurement signals having values corresponding to the values of the parameter as it varies;
• memory means for storing at any one instant in time the measurement signal having the largest value of all the measurement signals generated during the predetermined time period;
• processor means for repetitively comparing the value of the stored measurement signal with the value of a subsequently-generated measurement signal and for storing the subsequently-generated measurement signal in place of the stored measurement signal in the memory means if the value of the subsequently-generated measurement signal is greater than the value of the stored measurement signal;
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• display means for displaying a number corresponding to the value of the measurement signal remaining in the memory means at the end of the predetermined time period, whereby the maximum value of the parameter occurring during the predetermined time period is displayed.

Apparatus for measuring and displaying the minimum value of a parameter of an internal combustion engine which varies in value comprising in combination:

• means for generating during a predetermined time period a series of time-spaced digital measurement signals having values corresponding to the values of the parameter as it varies;
• memory means for storing at any one instant in time the measurement signal having the smallest value of all the measurement signals generated during the predetermined time period;
• processor means for repetitively comparing the value of the stored measurement signal with the value of one or more subsequently-generated measurement signals and for storing the subsequently-generated measurement signal in place of the stored measurement signal in the memory means if the value of the subsequently-generated measurement signal is less than the value of the stored measurement signal;
• and
• display means for displaying a number corresponding to the value of the measurement signal remaining in the memory means at the end of the predetermined time period, whereby the minimum value of the parameter occurring during the predetermined time period is displayed.

Apparatus for determining the timing of an internal combustion engine having a plurality of chambers fitted with ignitors which are operated by a series of time-spaced firing pulses and having a timing mark which passes a timing location when the engine is located at a predetermined number of degrees prior to a top dead center position, said apparatus comprising:

• a register for storing the predetermined number of degrees;
• manually operable means for entering the predetermined number of degrees into the register;
• generator means for generating a timing pulse when the timing mark passes the timing location;
• clock means for producing clock pulses at a predetermined rate;
• a counter means for counting clock pulses;
• gate means for transmitting clock pulses to the counter means between the occurrence of a first and second one of the firing pulses to obtain a first count proportional to the time period between the first and second ignition pulses, and for transmitting clock pulses to the counter means between the occurrence of one of the firing pulses and the timing pulse to obtain a second count proportional to the time period between the last said firing pulse and the timing pulse;
• processor means for generating a timing number proportional to the second count divided by the first count plus the predetermined number of degrees;
• and
• display means for displaying a timing display number proportional to the timing number in digital form.

Apparatus for measuring and displaying a parameter useful for diagnosing an internal combustion engine comprising:

• transducer means for generating a digital measurement signal corresponding to the value of the parameter produced by the engine;
• display means including a face for displaying a digital measurement number indicative of the value of the parameter;
• memory means for storing first and second linearization constants;
• processor means for multiplying the value of the digital measurement signal times the value of the first linearization constant to produce a first partial result signal, for multiplying a power of the value of the digital measurement signal times the value of the second linearization constant to produce a second partial result signal, and for summing the values of the first and second partial result signals in order to produce a digital calculated signal, whereby the value of the digital measurement signal is linearized;
• and
• display controller means for enabling the display means to display the digital measurement number in response to the digital calculated signal.