Abstract: A seal between the opposing surfaces of two joined members, wherein at least one of the surfaces is disposed about a bore or cavity. A salient portion (edge or bead) is formed on at least one of the surfaces and around the bore or cavity, and a gasket of resilient material is disposed between the surfaces to overlay the salient portion. The portions of the opposing surfaces other than the salient portion are substantially planar, and the gasket extends across the salient portion. Each salient portion is preferably formed by its opposing surface being disposed at an incline to an apex and the gasket is configured to have a thickness such that some extending portion thereof aside the salient portion is subjected to compression, of lesser degree than that applied by being at the salient portion.

Abstract: Method and apparatus for plasma flame-spraying coating material onto a substrate by means of passing a plasma-forming gas through a nozzle electrode, passing an arc-forming current between said nozzle electrode and a rear electrode to form a plasma effluent, introducing coating material into the plasma effluent, passing the plasma effluent axially through a wall shroud extending from the exit of said nozzle electrode and forming a flame shroud for the plasma effluent at least within the wall shroud.

Abstract: The invention relates to a method and apparatus for measuring the temperature of an object within a temperature range of between about 100.degree. C and about 2700.degree. C by deriving a signal indicative of the temperature of the object from the total radiation within a limited wavelength range extending from about 8 to about 14 microns. In one form of the invention, a device is provided which includes a radiation detector, a reference member, a temperature control device for automatically maintaining the temperature of the reference member at a substantially constant value, a device for alternately directing radiation from the object and from the reference through a filter to the radiation detector, a signal processing system for receiving signals from the radiation detector and outputting a signal indicative of the temperature of the object, responsive to the difference between the radiation detected from the object and from the reference member.

Abstract: Method and apparatus for plasma flame-spraying coating material onto a substrate by means of passing a plasma-forming gas through a nozzle electrode, passing an arc-forming current between said nozzle electrode and a rear electrode to form a plasma effluent, introducing spray coating material into the plasma effluent, passing the plasma effluent axially through a wall shroud extending from the exit of said nozzle electrode and forming a hot gas shroud for the plasma effluent at least within the wall shroud.

Abstract: A stepping motor control circuit for precisely controlling the motion thereof. The control circuit energizes the motor windings according to the design sequence for rotation in a given direction. Each winding is energized by a signal having an ascending staircase for its leading edge, a descending staircase for its trailing edge and a steady state level between the leading and trailing edges. The ascending staircase and the descending staircase each comprise one quarter of the terms for each winding energizing signal. The steady state level occurs for one half the time of each energizing signal. The total number of steps in all ascending and decending staircases is controlled and selects the total rotation of the motor. When the motor reaches the desired position whether in the middle of a staircase or not, the signals coupled to the stepping motor windings are frozen at the level when the total step count is reached.

Abstract: A tunable electrical filter is disclosed wherein an RC (resistor-capacitor) network comprising a plurality of switchable capacitors among the components determining the time constant of the filter provides a given minimum value of filter time constant and, therefore, a given minimum bandwidth, when all the capacitors are continuously connected in the network. Each capacitor is coupled to the network through the output means of an electronic switching means. A pulse generator connected to the input means of said switching means provides a train of pulses having an adjustable ON-time to OFF-time ratio. When all the capacitors are periodically switched by the output of the pulse generator, the effective filter time constant increases from said given minimum value as the ON-time compared with the OFF-time decreases. The pulse generator is provided with control means for adjusting the ON-time to OFF-time ratio.

Abstract: There is described an improvement for an apparatus employing a plurality of operational elements adapted to cooperate for producing an electrical signal representing the variation of an ordinate quantity with respect to an abscissa quantity changing at a controlled rate. At least one of said elements requires an adjustment during operation such as is capable of causing spurious transients in the electrical signal. The apparatus further comprises a filter for filtering the electrical signal before feeding the signal to a suitable utilization device such as a recorder. The improvement includes control means which operate to interrupt the ordinate quantity signal and cut off the filter response prior to any element adjustment. There is disclosed means for storing the output of the filter at cut off and for memorizing the point along the impulse characteristic of the filter at which cut off takes place.

Abstract: Sample preparation apparatus for forming a thin layer of diluted blood specimen on a substrate by centrifugal force includes a sample probe having coaxial blood and diluent conduits coupled to respective reversibly-drivable peristaltic pumps having forward operation intakes connected to a diluent supply. A one-way clutch limits the diluent pump to forward operation and the pumps are geared to produce a blood-to-diluent displacement ratio of 2:1. A substrate holder is mounted on a carriage for selective insertion into and removal from a sealed centrifuge chamber in which it is spun at a high angular rate by a drive motor. Means are provided to form a curtain of flowing liquid within the chamber surrounding the spinning substrate to collect spun-off blood particles and aerosol. The liquid forming the curtain is drained by an exhaust pump which operates after spinning has ceased so as to create a partial vacuum for draining off residual aerosol prior to unsealing the centrifuge chamber.

Abstract: An a.c. to d.c. converter is disclosed which includes two resetable integrators each for sampling an alternate half-wave of the a.c. voltage to be converted. During each alternate half-wave, when a given integrator is not integrating the input signal, the integrator output is sampled by an analog memory circuit. After the sampling has taken place, the integrator which has been sampled is reset so that it can again operate properly during the succeeding half-wave. The difference of the output for both analog memory circuits is formed so that the d.c. component of the incoming a.c. signal is removed and the remaining residual ripple in the output results only from changes in amplitude of the a.c. signal itself from one-half wave to the next.