Abstract: A weld monitoring and evaluating circuit (10) for non-destructively determining if a just-completed weld is a satisfactory or an unsatisfactory weld. The circuit is used to derive the temperature at the weld zone in real time by determining the total power input to the weld zone, taking into account losses experienced at the weld zone, and dividing the result by the thermal mass of the weld zone. The predicted temperature at the weld zone is compared against an electrical signal representing at least a minimum desired welding temperature needed to be attained at the weld zone to produce a satisfactory weld at the time that the stud (16) contacts the weld pool (18a) (e.g., the "plunge event"). If the derived weld temperature signal has exceeded the reference signal at the time the plunge event occurs, then it is assumed that a satisfactory weld has occurred.

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: The specification discloses an improved weigh scale of the dual beam type having large and small flow buckets adapted to receive a flow of fluid therein, and an encoder connected to a ball screw having a poise weigh driven by a drive motor for keeping the scale continually balanced while a fluid is being introduced into one of said flow buckets, and having a power supply circuit, a pulse encoder circuit, and a poise control circuit for operation thereof, the improvement including an improved poise control circuit having low gain with high integration for use during the run mode, but being switchable to a circuit having high gain and derivative action during the calibration mode.

Abstract: The specification discloses a two-directional switched driver for use either independently or in a method of controlling production processes and apparatus therefor. The driver, whether used independently or in a process controller, utilizes polarity signals and a retriggerable timer to produce separate forward and reverse output signals which may be used to drive reversible motors or two-directional actuators by way of standard switching techniques. Examples of such uses are the use of most any reversible motor, or two-directional actuators to control mechanical, pneumatic or hydraulic circuits, such actuators operated by the driver may be rotational or non-rotational in nature.

Abstract: The specification discloses a novel method for controlling production processes of a pneumatic, electrical or hydraulic nature and apparatus therefor. The method, and therefore the apparatus for performing said method, counteracts any process change by utilizing the error difference and the rate of change of the error difference between a feedback signal related to a current condition of the process and a desired value related to the desired condition of the process.The error difference and rate of change and then utilized to produce a correction signal which is adapted to remain unchanged as long as the process being controlled, and the desired value signal, both remain in static condition, but which also has a unique look ahead feature such that said correction signal attempts to become saturated as soon as a new desired value is supplied, or a process change occurs.