Abstract: An earthquake actuated device includes a flapper-valve adapted to block a gas flow and a micro switch for closing or opening a circuit. A seismic sensor responds to accelerations characteristic of an earthquake. The sensor cooperates with a magnet in a flapper arm to hold the flapper-valve open. When the sensor experiences sufficient motion, the flapper arm is released and the flapper-valve falls onto a seat, thereby closing and blocking the gas flow. The closing of the flapper-valve is further coupled into an actuation of the micro switch, thereby opening or closing the circuit.

Abstract: An earthquake actuated micro switch includes a ball which falls into a micro switch actuating position when disturbed. The ball normally resides in a shallow ball seat. A sufficient disturbance causes the ball to escape the ball seat, and fall into a switch seat. When the ball comes to rest in the switch seat, a lower surface of the ball pushes a micro switch actuator, thereby actuating the micro switch.

Abstract: An earthquake actuated automatic gas shutoff valve having a valve bottom portion with a generally horizontal floor having a ball seat and a valve seat surrounding a gas outlet passageway. A ball having an elastomeric outer surface is held in the ball seat and in the event of an earthquake, the ball is shaken out of the ball seat and rolls into the valve seat to stop the flow of gas. The ball can either be a solid elastomeric ball or a metal ball with an elastomeric outer coating.

Abstract: A flapper-type gas valve automatically closable by accelerations characteristic of earthquakes. The arm is held up in the "valve open" position by a magnet attracting a soft ferromagnetic armature. The armature can be displaced to release the flapper to close the valve, either by seismic accelerations or manually by novel magnetic means--the latter for testing or for non-seismic emergencies. The latter employ movable permanent magnets or electromagnets. Additional magnets are provided to hold the valve closed. Indicating means on the flapper shaft can be viewed through a window to see the valve status--open or closed. The electromagnetic modification provides remote status indication via a magnetically-actuated switch.

Abstract: An acceleration-responsive magnetic device for closing a valve or operating a switch or the like in response to a disturbance such as an earthquake. A pendulum operates to increase the length of a magnetic path, releasing a magnetic element to perform the desired actuation.

Abstract: A safey shutoff valve for insertion into a gas line or other fluid line, that closes in response to an electrical input pulse or to a seismic disturbance. A pivoted flapper arm is held in the open position by a permanent magnet embedded in it. When the magnetic attractive force is reduced enough, the arm swings down by gravity into the closed position and a primary flapper seal element seals the valve seat. Line pressure keeps it closed. The magnetic holding force may be reduced by means of an opposing electromagnet or by the mechanical displacement of a ferromagnetic ball. The valve is manually reset by turning a reset shaft to raise the flapper arm to the open position. The reset shaft also raises a secondary flapper to uncover a small bypass tube to bleed off any residual line pressure; this bypass is automatically closed when the valve closes. No standby power is required.

Abstract: A seismometer system which provides readouts of the time integral (Cumulative Absolute Velocity or CAV) of the acceleration time history of an earthquake. CAV is found to be a measure of the structural damage potential of an earthquake. Three triaxial low frequency acceleration sensors are connected into a digital computer system. Each sensor has a capacitive pickoff, whose capacitances determines the length of an electrical pulse; the pulse gates high-frequency clock cycles into a counter. The counts are summed to give the time integral. A microprocessor provides for periodic re-zeroing and other calibration functions, and for the actuation of alarms, relays and electrical pulses for utility shutoff and the like at predetermined levels of CAV. The acceleration time history of the earthquake is stored in the memory for later retrieval if desired. The whole system is contained in a small inexpensive package.

Abstract: A device for recording directly the strain or distortion of a structural space as caused by an earthquake. Two similar light, flat rigid A-frame-like members are attached to points near the floor and ceiling, e.g., of a room, with their apex portions facing each other and overlapping. A displacement recorder is mounted in the overlap region. Earthquake distortion or strain in buildings occurs commonly as relative lateral displacement between a floor and a ceiling; the A-frame members transmit such displacement directly to the recorder. The installation may lie flat against a wall and be enclosed by a shallow cover.

Abstract: A mechanical seismic instrument for recording relative horizontal displacements between the base and foundation of base-isolated buildings or other large structures during earthquakes. A rigid tripod-like arm is connected to the base of the structure; on the other end of the arm is a marking stylus. A record plate is connected to the foundation. When base and foundation move relative to one another, the stylus scribes a record trace on the record plate. Arm and record plate are mounted respectively on mounting plates which are connected and covered by a flexible enclosure. Timing marks on the record trace may be made by striking devices which tap against the shank of the stylus.

Abstract: A three-axis scratch-recording accelerograph of the type installed in large structures to record peak magnitudes of earthquake or like motion. Hard styli coupled to seismometer elements scratch or engrave record lines on small stationary metallic record plates, which are suitably coated. No standby power is required and the records are resistant to heat, liquids, and mechanical damage. The instrument embodies various improvements over that in my prior U.S. Pat. No. 3,974,504 respecting the reed spring suspension of the proof mass; transit clamping; the magnifying lever system; and electrical status indication.

Abstract: A seismic instrument or accelerograph for recording the spectra of strong earthquake shocks or the like, having a series of mechanically-resonant recording units which trace or "scratch" linear records with styli on metallic record plates. No electrical or other power source is needed to make the records, so that the instrument may stand by for many years without attention. The case has, typically, about sixteen separate compartments with a recording unit installed in each. Each unit has a different natural (resonant) frequency, in the range between about 1 to 32 Hz. The record plates are all alike, except for keying or locating grooves, and all the recording units are made to have about the same sensitivity in terms of stylus deflection per unit acceleration. A problem addressed here is that in any simple linear mass-spring system, the static sag (deflection of the mass at 1 g) is inherently related to the natural frequency by an inverse square law.

Abstract: A low-cost accelerometer having auxiliary pointers which hold its peak readings. It is suitable as a portable instrument for vehicle testing, or may be installed in a structure to hold or retain the maximum readings that occurred during an earthquake or other shock. The accelerometer comprises a cantilever-reed-type mass-spring system with an indicating pointer disposed so as to push a pair of light-weight balanced "tell-tale" or holding pointers which are mounted on light frictional pivots and record or hold the peak deflection of the main pointer. The working parts are mounted in a flat case filled with a damping fluid. Reset knobs for the holding pointers are located on the outside of the case. The frictional torque of their pivots is adjustable from outside. A typical range for the instrument is .+-. 2 g.

Abstract: A three-axis instrument for recording peak accelerations in earthquakes and like kinds of shocks. Recording is by scratches made by hard styli on small metal record plates. No power source and no maintenance are required. The seismic recording elements have novel configurations of mass, spring, and lever arm which permit improved combinations of sensitivity and natural frequency for any given magnitude of stylus friction. For example, a sensitivity of 0.25 cm per g with a natural frequency of 32 Hz may be attained, where error due to a stylus frictional force of 70 mg is less than 1 percent of full-scale. Both hydraulic and magnetic dampers are employed. The latter also provide motional electrical signals for use in calibration.

Abstract: An earthquake actuated automatic gas shutoff valve having a valve bottom portion with a generally horizontal floor having a ball seat and a valve seat surrounding a gas outlet passageway. A ball having an elastomeric outer surface is held in the ball seat and in the event of an earthquake, the ball is shaken out of the ball seat and rolls into the valve seat to stop the flow of gas. The ball can either be a solid elastomeric ball or a metal ball with an elastomeric outer coating.