Abstract: A system for self-testing an acoustic monitor includes a memory that stores a reference acoustic power of a reference acoustic signal; a digital signal processor (DSP) that computes a real-time acoustic power spectrum of background noise in a frequency range of about 20 Hz to about 80 kHz; a microphone including analog signal conditioning circuitry that receives an acoustic test signal at a test frequency and sound pressure level (SPL), the SPL including an attenuation level; and a processor that compares a measured acoustic power at the test frequency with a calculated acoustic power of the acoustic test signal, the calculated acoustic power including the reference acoustic power and the attenuation level; where the acoustic monitor includes the DSP in signal communication with the microphone.

Abstract: An electronic monitor is disclosed which continuously monitors the sound emanating from rotating machinery, non-rotating equipment, or any other sound-producing process or environment, as a means of detecting abnormalities and thus determining the operating condition thereof. The monitor continuously computes the power spectrum of the monitored sound and has two modes of operation: learn and operate. The monitor is placed in the learn mode during a time when the machine or process to be monitored is known to be operating normally. During the learn mode, the maximum and minimum acoustic power output from each of a plurality of digital bandpass filters is continuously maintained and updated in data memory as the acoustic signature of the machine or process being monitored.

Abstract: An apparatus (10) is disclosed including a friction clutch (12) and an overload apparatus (14) connected in parallel between an input (16) and an output (18). Encoders (20, 22) are provided for separately detecting the rotational positions of the input (16) and the output (18). A microcomputer controller (580) controls actuation of the friction clutch (12) and the overload apparatus (14) in response to the rotational positions detected by the encoders (20, 22) allowing the clutch (12) to bring the output (18) to be generally aligned with a select rotational position of the input (16) at which time the overload apparatus (14) can be actuated to rotatably relate the input (16) and the output (18) at the select rotational position and actuation of the clutch (12) can be removed. The microcomputer controller (580) also removes actuation of the overload apparatus (14) when the encoders (20, 22) detect rotation of the input (16) relative to the output (18) from the select rotational position.

Abstract: A torque and/or rotational control apparatus is disclosed in a preferred form of a brake (10) including a plurality of pairs of actuators (18) positioned on opposite sides of a friction disc (16) by spacers (120) having tear shaped cross sections. The pads (32) of the actuators (18) are removably held by a slideable locking pin (70) biased by a spring (80) into an aperture (68) of a backing plate (62) for the pad (32). A notch (64) formed in the pad (32) and the backing plate (62) is slideably received on a rail (66) axially extending from the housing (35) of the actuator (18) to prevent rotation about the locking pin (70). The friction disc (16) includes elongated and shortened fins (42, 43) upstanding between and equally circumferentially spaced intermediate first and second component discs (40, 41). The fins (42, 43) are free of circumferential interconnections to allow air to radially pass freely between the fins (42, 43).

Abstract: By measuring the power supplied to a compressor motor and by measuring four temperatures within a mechanical vapor-compression system, it is possible to develop a device for measuring and/or displaying the specific coefficient of performance of the mechanical vapor-compression system. The use of the temperatures and power supplied to the compressor motor can be used with information on motor losses and a typical temperature-enthalpy and a typical pressure-entropy diagram to allow substantially instantaneous computation of the actual specific coefficient of performance of a mechanical vapor-compression system as it operates. The measuring device can usually be installed totally external to a building in which the mechanical vapor-compression system is being used as a cooling system, or as a heat pump for heating and cooling.