Abstract: The specification discloses an electronic dynamic balance leak testing system utilizing a "live zero", wherein a source of test medium at a predetermined desired pressure or vacuum is connected to a part to be tested, and after the part is filled with the test medium, and an interval is provided for the system to stabilize the affects due to wave front oscillations, the test part is momentarily isolated from said test media and a microcomputer system is utilized, both to cause said isolation, and to measure the differential pressure existing at two points during the test. In a modification of our system which can dynamically project leak and accept or reject parts much sooner because of this projection feature, the rate of change of the differential pressure transducer is examined and is compared to a curve which is characteristic of the rate of change of a volume which is experiencing a predominately leak based change of pressure.

Abstract: The specification discloses a method and apparatus for calibrating liquid flow meters of all types. The system includes a scale for dynamically determining the weight of a liquid flowing through a flow meter, together with means for measuring the flow through the flow meter being tested. In the case of a glass tube flow meter, a float detection system is used, whereby the operator will set the flow through the flow meter to a desired point, use the float detection system to make certain the float stays in a fixed position during the test, as well as to locate the float from a reference point, and use the system to measure the flow through the flow meter during a fixed period of time, thereby obtaining a reading, in engineering units, for each predetermined position of the float.

Abstract: A method and apparatus for hot testing on a production basis, automobile engines as they come off the assembly line for performing a final check on such engines before they are installed in the automobile. The engines are tested for exhaust emissions at three points or KEY MODES of operation at which emission related engine malfunctions are most likely to appear. These points of operation are high cruise, low cruise, and idle. The engine, after it comes off the assembly line is placed in a production test stand wherein the connections for water, oil and exhaust are made, the engine is started, accelarated to the high cruise speed, and allowed to warm up for a predetermined time, after which time, measurements of hydrocarbons and carbon monoxide are taken and an appropriate indicator light lit to indicate that the engine either is within limits at this speed, or does not pass for some reason. The same procedure is followed in the low cruise and idle speeds.