Engine analyzer

• US 4,375,672 A
• Filed: 05/05/1980
• Issued: 03/01/1983
• Est. Priority Date: 05/07/1979
• Status: Expired due to Term

• Current Assignee: KK Toyota CHUO Kenkyusho
• Original Assignee: KK Toyota CHUO Kenkyusho
• Inventors: Kato, Takayuki, Tsuji, Toshio, Konishi, Kiyokazu
• Primary Examiner(s): Krass, Errol A.
• Application Number:
  US06/146,481
• Time in Patent Office: 1,030 Days
• Field of Search: 364/424, 364/550, 364/551, 364/431, 73/116, 73/117.2, 73/117.3, 324/278, 324/379, 324/384, 324/393
• US Class Current: 701/102
• CPC Class Codes: G01M 15/05 by combined monitoring of two or more different engine parameters
• CPC Class Codes: G01R 31/007 using microprocessors or computers

Abstract

During analysis, sensors are connected to portions of an engine and thereabout and a starter driven by an auxiliary battery incorporated in a system. An engine of a motor car and electrical systems thereabout are automatically diagnosed by use of a computer to discriminate the good or bad condition thereof, whereby the results of diagnosis are outputted as a print out and a fault point or points is indicated by an indicating device. The indicating device successively shows in graphic display the contents of working performed by a worker in the predetermined order of working. Additionally, an engine drive control section automatically sets the analyzer in one of modes including an engine stopped mode, a cranking driven mode, an idling operation mode and the like in accordance with point or points of diagnosis of the vehicle being diagnosed.

Claims

1. An engine analyzer comprising:

detecting means including a plurality of sensors which when engine analysis is to occur are connected to given portions around an engine such as an internal combustion engine for detecting the characteristics of the respective given portions as electric signals;

engine drive control means including an auxiliary electric power source, which when engine analysis is to occur is connected from outside to an engine starter motor as the power source for said engine starter motor which is independent from the battery connected to the engine, and a control circuit capable of controlling a drive circuit of said engine starter motor from outside;

signal processing means for converting electric signals fed from said detecting means and said engine drive control means to indicate the characteristics of the respective portions of the engine into signal aspects to be easily processed;

centralized control means including a computer for successively operating and processing the outputs fed from said signal processing means according to a preset program, comparing and determining said operation results with values preset in accordance with the respective signals and feeding command signals for the inspection and diagnosis of the engine; and

diagnosis indicating means being operable by the command signals fed from said centralized control means, including means for displaying each portion being inspected on a graphic display of a planar pattern, means for successively instructing the predetermined work procedures to an operator and means for giving the results of diagnosis of predetermined items of inspection.

2. The engine analyzer as set forth in claim 1, further comprising:

a plurality of diagnosing probe means for feeding inspection signals from outside an engine and engine accessory to a high voltage circuit section in an engine ignition circuit; and

multi-cylinder engine inspecting means including a plurality of electric power sources for generating inspection signals in accordance with the purposes of inspection and a switching circuit for separately supplying the inspection signals selected in accordance with the respective cylinders to said plurality of diagnosing probe means.

3. The engine analyzer as set forth in claim 2, further comprising:

remote control means having a switch for carrying out, discontinuing or interrupting a set mode of said engine analyzer.

4. The engine analyzer as set forth in claim 3, further comprising:

fault point indicating means for indicating the condition of inspection on the points of inspection and the results of inspection.

5. The engine analyzer as set forth in claim 4, wherein:

said diagnosis indicating means further comprises;

an item indicating section for indicating each item under inspection; and

a determined value indicating section for indicating determined values for the items of inspection.

6. The engine analyzer as set forth in claim 5, further comprising record means for recording the measured and determined values and the results analyzed based on the above measured values.

7. The engine analyzer as set forth in claim 6, wherein:

said fault point indicating means has a graphic display of planar pattern for showing the fault point in figures with letters and signs.

8. The engine analyzer as set forth in claim 7, wherein said remote control means further comprises timing light means which includes:

a timing light for flashing in synchronism with an ignition signal detected by the engine ignition circuit; and

a switch for regulating the flash timing of said timing light through outputs fed from said centralized control means.

9. The engine analyzer as set forth in claim 8, wherein said detecting means has a battery sensor.

10. The engine analyzer as set forth in claim 9, wherein said engine drive control means comprises:

two switches contacting polarities of a vehicle-mounted battery through battery sensors, respectively;

two other switches including one inserted between one of said former two switches and an engine control terminal and the other inserted between one of said former two switches and a charger;

a switch drive circuit connected to said former two switches and latter two switches for driving said switches;

an auxiliary power source having a potential equivalent to said vehicle-mounted battery;

a charge discriminator circuit connected to said auxiliary power source for discriminating the charge condition;

a charger connected to one of said former two switches and one of said latter two switches;

a power relay for connecting said auxiliary power source to said vehicle-mounted battery; and

a polarity discriminator circuit connected to said battery sensors for discriminating the conditions of said battery sensors.

11. The engine analyzer as set forth in claim 10 wherein said multi-cylinder engine inspecting means comprises:

a switching circuit section including;

a plurality of high voltage switches connected to a group of detectors and applied thereto with high voltage; and

a switch drive circuit for actuating and controlling said high voltage switches in a manner to combine the ignition order with the inspection purposes.

a first inspecting section including;

a DC high voltage power source for generating a DC high voltage;

a capacitor connected to said DC high voltage power source; and

a divider circuit connected to said DC high voltage power source, for dividing an output voltage from said power source;

a second inspecting section including;

a DC constant voltage power source for delivering a stabilized DC voltage; and

a plurality of resistors for dividing said output voltage from said DC constant voltage power source;

a third inspecting section including;

a resistor circuit selectively connected to said plurality of high voltage switches, for dividing output voltages from said high voltage switches;

a boosting transformer connected to a transistor controllable by a signal process circuit section;

a fourth inspecting section including;

a power relay included in an output circuit of said transistor, for on-off operating said transistor;

a diode connected to a secondary winding of said boosting transformer, for half-wave rectifying a high output voltage from the secondary wiring; and

two resistors connected to the secondary winding of said boosting transformer, for dividing an output voltage from said boosting transformer; and

a relay drive circuit connected to said power relay for driving and controlling said power relay.

12. The engine analyzer as set forth in claim 11, wherein said detecting means comprises:

a battery current sensor for detecting a current flowing from said vehicle-mounted battery to a starter motor;

a coil current sensor connected to an ignition coil, for detecting a current flowing to said ignition coil;

detachable clips connected to said ignition coil, a point of an interruptor and the engine body, respectively; and

voltage detecting probes connected to said vehicle-mounted battery and said point, respectively, for detecting voltages from said vehicle-mounted battery and said point.

13. The engine analyzer as set forth in claim 12, wherein said probe means comprises:

a diagnosing probe inserted between said ignition plug and a plug cord; and

a diagnosing attachment inserted between an output terminal of said ignition coil on the secondary winding and a coil cord.

14. The engine analyzer as set forth in claim 13, wherein said signal processing means comprises:

an input circuit connected to the group of sensors of said detecting means, the engine drive control means and the multi-cylinder engine inspecting means;

a battery voltage signal process circuit connected to said input circuit;

a battery discharge signal process circuit connected to said input circuit;

a starter current signal process circuit connected to said input circuit;

a primary voltage signal circuit connected to said input circuit;

a primary current signal process circuit connected to said input circuit;

a point voltage signal process circuit connected to said input circuit;

a trigger signal process circuit connected to said input circuit;

an ignition signal process circuit connected to said input circuit;

a plug discharge voltage process circuit connected to said input circuit;

a plug leaking current process circuit connected to said input circuit;

a high voltage circuit applying signal process circuit connected to said input circuit; and

a high voltage circuit current signal process circuit connected to said input circuit.

15. The engine analyzer as set forth in claim 14, wherein said centralized control means comprises:

an interface connected to the process circuit of said processing means;

a control panel for feeding the specific predetermined items of the diagnosis;

an input device connected to said control panel;

a computer connected to said input device and said interface for operating and processing the outputs from the process circuits of said signal processing means so as to make the determination; and

a memory section connected to said computer for storing the specific predetermined items of vehicle to be diagnosed, such as running distances, ignition systems, the reference values for each vehicle.

16. The engine analyzer as set forth in claim 15, wherein said fault point indicating means comprising:

an indicating section consisting of;

said planar pattern;

a box portion having partition frames corresponding to the items of inspection of said pattern; and

flashers arranged for the respective partition frames; and

an indication drive circuit connected to the flashers of said indicating section for indicating the portions of diagnosis and fault points in response to signals from computer.

17. The engine analyzer as set forth in claim 16, wherein said record means comprises:

a printer for printing the determined results, measured values, and reference values on printing paper.

18. The engine analyzer as set forth in claims 2 or 15, further comprising:

plug discharge voltage detecting means for applying high voltages to the plugs of the respective cylinders of the engine, detecting the discharge dielectric breakdown voltage generated between the electrodes of the plugs and processing the detected discharge dielectric breakdown voltages so as to detect unusual sooty conditions of the spark gaps of the plugs.

19. The engine analyzer as set forth in claims 2 or 15, further comprising:

plug insulation resistance detecting means for detecting plug leaking currents flowing between the plugs and the engine body when high voltages are applied to the plugs of the respective cylinders of the engine, and processing the detected plug leakage current so as to detect the insulation resistances of the plugs.

20. The engine analyzer as set forth in claims 2 or 15, further comprising:

high voltage circuit dielectric strength detecting means for detecting voltage leakage in high voltage circuits and detecting the discharge dielectric strength and abnormalities of the high circuit section of the engine comprising a coil cord, a distributor and a plug cord based on the minimum values of the voltage leakage thus obtained, when the engine is cranked and high voltage is applied to said high voltage circuit section of the engine in synchronism with the top dead center or the ignition timing of the engine.

21. The engine analyzer as set forth in claims 2 or 15, further comprising:

high voltage circuit resistance detecting means for detecting the current flowing through the high voltage circuit when the engine is cranked in a condition where portions between the plugs and the plug cords of the respective cylinders of the engine are grounded with cords of low resistance and high voltages are applied to the high voltage circuit section of the engine consisting of a coil cord, a distributor and a plug cord in synchronism with the top dead center or the ignition timing of the engine and processing the detected high voltage circuit current so as the detect the resistance value of said high voltage circuit section.

22. The engine analyzer as set forth in claims 2 or 15, further comprising:

battery capacity detecting means for detecting the voltage drop rate of the battery when a high current is applied from the battery of the engine to a load of low resistance and processing the detected voltage drop rate so as to detect the battery capacity.

23. The engine analyzer as set forth in claims 2 or 15, further comprising:

battery terminal resistance detecting means for detecting the potential difference between the center electrode and the terminal of the battery and the current flowing through a load of low resistance when a high current is applied from the battery of the engine to the load of low resistance and processing the detected potential difference so as to detect the resistance value of the battery terminal.

24. The engine analyzer as set forth in claims 2 or 15, further comprising:

engine compression ratio balance detecting means for detecting the current flowing from the battery to the starting motor when the engine is cranked so as to apply the peak value of the current to the respective cylinders, and detecting the relative ratios between compression ratios of the respective cylinders of the engine by calculating the relative ratios.

25. The engine analyzer as set forth in claims 2 or 15, further comprising:

belt slip rate detecting means for detecting the slip rate of the belt by comparing the frequencies of the primary voltage signal of the coil with the frequencies of the ripple component of the output from the alternator, and subsequently, detecting the difference between the comparative values of both when the engine is repidly accelerated.

26. The engine analyzer as set forth in claims 2 or 15, further comprising:

starter current detecting means for detecting the starter current flowing from the battery to the starting motor when the engine is cranked, and further, detecting an abnormality in the starting motor based on the value of the current.

27. The engine analyzer as set forth in claims 2 or 15 further comprising:

points resistance detecting means for detecting the contact resistance of the points in a manner that the points of the ignition systems are closed when the engine is stopped, and then, the current and voltage applied to the points are detected when the engine is turned on, and a ratio between the detected current and voltage is calculated.

28. The engine analyzer as set forth in claim 2 or 15, further comprising:

primary current resistance detecting means for detecting the resistance value of the primary circuit in a manner that the primary current flowing to the primary circuit of the ignition system is detected during idling of the engine, and simultaneously, the voltage of the battery is detected and the ratio between the detected primary current and voltage is calculated.

29. The engine analyzer as set forth in claim 10, wherein timing light means of said remote control means includes:

a Xenon tube, a focusing convex lens provided close to a light emitting portion of said Xenon tube; and

a trigger coil driven and controlled by said signal process circuit section, for triggering the Xenon tube.