Abstract: In a preferred embodiment, a steel ball having a surface coating of gold is magnetically held against each of negative and positive electrical switch contacts within a fenced-in space substantially filled with silicone fluid, the electrical switch contacts being alternately arranged in a circular series and being connected to a logic cell and mechanism adapted to count pulses resulting from each of breaking and making electrical contacts when the ball is jolted by vibration and to reset if at-least two consecutive pulses do not occur within half a second, and to send an alarm signal to a transmitter that transmits an alarm signal to a radio receiver, magnetic force lines being provided by a pole of a large bar magnet positioned behind the electrical switch contacts and a like-charge repelling-pole of a smaller bar magnet in front of and spaced-from the electrical switch contacts and ball.

Abstract: A vibration diagnosis method for a rotary machine is disclosed. The presence or absence of a self-excited vibration is determined by checking if a rotating speed is in a rotating speed range which allows the occurrence of the self-excited vibration, if an amplitude of a frequency component corresponding to a first order critical speed is larger than a predetermined level, and if phases at characteristic points of vibration signals change among cycles.

Abstract: By mounting unusual vibration transducer apparatus consisting of a piezo-electric vibration detecting member, a pre-amplifier including a gain adjust knob, a comparator including level adjust knob, a monostable multivibrator including a pulse width adjust knob, a preset counter including preset value setting switch, a flip flop memorizing signals, an amplifier amplifying signals, and an output circuit at a machine tool like a grinding machine, a lathe, a milling machine, a planer, and/or a drilling machine, or by mounting only a piezo-electric vibration detecting member and installing the other components at a separate position outside a specified machine tool, vibrations produced during machining work are taken out by a comparator as high or low signal and alarm is then issued when such a vibration reaches the preset value of the counter, causing rotation or travel of a tool to stop or feed of workpiece to stop, and/or causing the rapid infeed rate of wheelhead to be changed to an adequate roughing feedrate.

Abstract: The vibration of a moving device which has repetitive movements, for instance a rotary compressor, are sensed at the outer case and analyzed in real time in both the time and frequency plane. For the time analysis the envelope of the signal is generated; for the frequency analysis a fast Fourier transform is performed and separate power spectra for fractions of a revolution are produced. The signatures are compared with those of an acceptable device to identify rejects and abnormalities at a particular position of a moving part.

Abstract: From the viewpoint of the preventive maintenance operation of a rotary machine, it is a very important subject to monitor the shaft vibration of the rotary machine and grasp the operating state of the machine. This invention relates to input processings in the case of executing the frequency analysis of a shaft vibration signal by digital processings.This invention describes the rotational frequency synchronization of a sampling frequency, the phase synchronization of the rotary machine to a reference phase, the relationship between an analytical wave number and a sample nunber, etc. in that case.

Abstract: A surge counter for a rotating compressor is provided which detects surging by monitoring the vibration signal from an accelerometer mounted on the shaft bearing of the compressor. The circuit detects a rapid increase in the amplitude envelope of the vibration signal, e.g., 4 dB or greater in less than one second, which is associated with a surge onset and increments a counter. The circuit is rendered non-responsive for a period of about 5 seconds following the detection which corresponds to the duration of the surge condition. This prevents multiple registration of counts during the surge period due to rapid swings in vibration amplitude during the period.

Abstract: Sound monitoring device for an industrial installation to detect possible impacts of stray bodies including at least one set of two sound detectors arranged in contact with the wall of the installation or in its vicinity, and a measuring and alarm circuit. The detectors are connected to this measuring circuit which includes a device for measuring the separation in time between the reception of the sound waves at one and the other detector, a comparator for this separation with at least one set of two predetermined values, and an alarm which is triggered if the separation in time falls between the two predetermined values. The invention is particularly useful for surveillance of the primary circuit of a pressurized water nuclear reactor.

Abstract: A switch and alarm system capable of detecting any one or more of the conditions of angular tilt, vibration or sudden movement includes a conically shaped movable contact suspended within an aperture in a fixed contact. The cone forming the movable contact is preferably suspended with its apex down to thereby render it inherently unstable, and hence sensitive to any applied vibrations. The sensitivity of the switch to the conditions to be detected can be adjusted by varying the height of the movable contact relative to the stationary contact to thereby vary the spacing between the two contacts. In addition, the radial position of the cone relative to the aperture in the stationary contact can be adjusted to permit the switch to be used in a variety of applications.

Abstract: An apparatus and method for detecting overstroke, understroke and/or overspeed, underspeed conditions in vibratory equipment includes a vibratory member mounted on the equipment to vibrate therewith and to operate solid-state switches over a large number of cycles. The preferred switches are Hall effect switches operable by a magnet carried by the vibratory member. During normal vibratory motion, a normal stroke Hall effect switch resets a timing means which will operate as a missing pulse detector and will generate an abnormal pulse if it is not reset during a predetermined period of time. If the amplitude is too large, the overstroke Hall effect switch is operated and causes an abnormal condition pulse. A control circuit means is operable by an abnormal pulse to generate an alarm and/or shut down the vibrating equipment.

Abstract: A system for detecting whether a machine is in the normal or abnormal state by comparing detected values of waveforms of signals such as vibration generated from the machine with a set value a plurality of times to indicate failure of the machine when the detected values reach the set value a predetermined number of times.

Abstract: To increase the responsiveness of a vehicle alarm system to, for example, unauthorized entry through windows, jacking up for removal of parts or vehicle theft as well violent impact by another vehicle, at least one position sensitive sensor has its output signal, which represents the instantaneous position of the vehicle stored after activation of the alarm system. Any change in that position is detected and triggers a warning device when the deviation exceeds a predeterminable amount. The position sensitive sensor may be a fluid-filled vessel the internal resistance of which is measured in a resistance bridge or it may be a variable inductance sensor which is connected to a frequency generator whose output signals are counted and compared with a given value. The system according to the invention may also serve as an accelerometer.

Abstract: An apparatus is provided for use as an onboard monitor and warning system attached to a fiberglas boom to detect potentially hazardous loads by detecting and counting acoustic emissions produced in the boom by the breakage of glass fibers. The monitor and warning system produce a warning signal when the number of acoustic emissions detected in a selected period of time indicates the existence of a potentially hazardous load. The apparatus includes a piezoelectric transducer which may be placed in contact with the surface of the fiberglas to produce electrical signals corresponding to pressure waves detected in the fiberglas. Apparatus is provided for distinguishing by the electrical signals those pressure waves which are acoustic emissions associated with the breakage of glass fibers from all other pressure waves.

Abstract: According to the invention, an accelerometer (G) is attached on the spring suspension (U) of the wheel (H) in question and capable upon passing of the vehicle over road irregularities to emit a decaying A.C. signal (S) with information on the oscillations of the axle (A) and the damping of the tire. After integration in an integrator (I) the signal is a measure of the difference between the damping of the shock absorber at expansion and at compression. This signal is compared in a comparator (K) with a reference signal (V.sub.ref) for the permissible damping difference and results in alarm (L) upon achieving said difference.

Abstract: A self-powered monitor unit with a tuned mechanical resonator power unit and a radio transmitter is mounted on every piece of rotating equipment being monitored, such as machinery with ball bearings. Bearing vibrations are sensed and the generation of a defect signal triggers the transmission of a radio signal modulated to identify the source. A central station receives and demodulates an emitted radio signal and displays the location with a fault condition. Large numbers of equipment can be monitored conveniently by unattended units.

Abstract: A refiner plate clash detection system and method for plate clash detection is provided herein. The system includes a receiver for a first signal having a significant increase in level at at least one distinct predetermined frequency related to the clash and the characteristics of the discs of the refiner. A filter is provided having a passband matched to pass the distinct frequency of the signal to provide a filtered output signal in which the center frequency of the passband of the filter is determined by the formulaf.sub.o =n.SIGMA..sub.Rwhereinf.sub.o is the center frequency (expressed in Hertz) of said passbandn=the number of segments at a given radius, per single disc and.SIGMA..sub.R =the sum of the rotational rates (expressed in Hertz) of the two discs enclosing a given refining volume.The filtered signal is then smoothed. A threshold level is established.

Abstract: An apparatus for detecting tip damages of a milling cutter comprising a motor for driving the milling cutter, a vibration detector mounted on the milling cutter, a vibration increase calculating device connected with the vibration detector for calculating vibration increase at every preset time, an abnormal vibration increase preset device, a comparator connected with the vibration increase calculating device and with the abnormal vibration increase preset device for comparing the output signals thereof, a memory connected with the comparator for storing abnormal signal from the comparator, and a gate connected with the comparator and with the memory wherein the gate is adapted to send out cutter abnormal condition indicating signals as an output only when both output signals from the comparator and the memory are abnormal.

Abstract: A monitoring system for detecting and indicating typical operating conditions, particularly vibration of an aircraft engine, wherein at least two measuring feelers such as accelerometers are exposed to the same conditions, the output signals from said feeler are compared with each other and logical means detect normal conditions when the output signals are equal, system defect conditions when the output signals differ from each other and alarm conditions when the output signals both exceed a safety limit. Such a system greatly increases the reliability and at the same time avoids false alarms.

Abstract: Method of monitoring equipment wherein a measured value signal in the form of an electrical a-c signal is fed to the measuring channel of an electric circuit and a mean value output signal is formed by the electronic circuit in accordance with the amplitude of the measured value signal, which includes setting an amplitude limit as a function of the mean value signal and the amplitudes of the measured value signal, automatically adapting the amplitude limit with a predetermined time constant to changes in the mean value signal, setting a limit of a number of occurrences when the amplitudes of the measured value signal exceed the amplitude limit, and activating an alarm if the occurrence limit is surpassed within a settable time period, and system for carrying out the method.

Abstract: A cylindrical movable member is forcedly fitted into two spaced annular leaf springs and disposed within a main detector body on its longitudinal axis with the lower end of the movable member put in point contact with the bottom of the main body. The leaf springs have outer peripheries fixed to the peripheral wall of the main body. The upper end of the movable member faces an operating rod for a limit switch having a spacing between them.

Abstract: A data acquisition system utilizing a microcomputer and incorporating a plurality of monitors each adapted to produce an electrical signal indicative of a physical condition of apparatus to be monitored. The electrical signals are fed via multiplexing equipment and analog-to-digital converters into the microcomputer which is equipped with print-out means. The system is such that the level of any one or all of the signals from the respective monitors can be printed out as well as a change in the condition of any signal. Means are incorporated into the computer for calculating and printing the trend (i.e., the slope of a plot of signal amplitude versus time) of a succession of stored signals from any monitor which would indicate a probable malfunction of a device being monitored and the probable time to failure. In the case where the signals from the monitors comprise vibration signals, the system performs an automatic frequency spectrum analysis whenever a probable or actual malfunction is detected.

Abstract: Novel device for detecting knot-like thick places in travelling textile threads, comprising a plate-shaped or rectangular vibratory member which is fixed at one end and has a straight edge at its other end. A plate-shaped piezoelectrical transducer element is fixed at one of the major surfaces of said vibratory member. A thread guiding member having a straight edge is arranged in essentially parallel relationship to the straight edge of the vibratory member such as to form a thread passage gap between said straight edges. Means adjust the width of said thread passage gap, and a case or support structure is provided for receiving the vibratory member, electromechanical transducer element and thread guiding member.

Abstract: An impact sensing detector for monitoring the operation of metal forming impact presses. The detector operates on an analog electric signal corresponding to the shock wave produced as the press ram impacts the fixed press platen and workpiece to produce a plurality of samples of the amplitude of said analog signal. These samples are digitized and compared against time corresponding standard samples previously derived from normal press operation. The detector may also be applied to other working areas of the press where waveform analysis can detect improper operation in order to avoid catastrophic failures. Predetermined differences between compared samples produce warning indicator signals which may be used to stop the press and also a fault analysis tool to help the press operator pinpoint the malfunction.