Abstract: A seal of the type resembling a padlock which comprises a plastic housing having a pair of apertures in the top surface for receiving the ends of a wire shackle. To provide evidence of tampering, by attempts to work a shackle end out of an aperture with a pair of pliers or the like, upwardly extending protuberance are provided on the upper surface of the body, which are mashed down by the tool being used in an attempt to open the seal, thereby giving evidence of tampering. When certain types of colored plastic are used for the seal body, the deformation of the protuberance causes them to turn white, giving further evidence of tampering.

Abstract: An infrared detector of sufficient sensitivity and stability to provide for the reliable detection of a glowing ember moving through an enclosed carrier system (duct or conveyor) in which a photo-resistive device for viewing the interior of the carrier is connected into suitable circuitry that does not respond to slowly changing ambient light, but which produces a voltage pulse in response to a moving glowing ember passing through the field of view of the detector; said voltage pulse being utilized to provide an output signal which may actuate an alarm or release extinguishant.

Abstract: A seal of the type having a hollow housing with internal resilient fingers for receiving a shouldered stud of a shackle into one end of the housing into locking engagement with the fingers, in which the opposite end is closed by a plug having resilient legs snapped into engagement with an internal recess in said opposite end. In one embodiment of the invention, the seal is formed of a single piece of molded plastic, with the plug being molded alongside the housing and being attached thereto by a flexible hinge or web.In another embodiment of the invention, the end of the shackle beyond the shoulder projects into a cavity between the resilient legs to lock said legs into the internal recess.

Abstract: A photo-electric smoke detector operating on the reflected light principle which has a rate detector for detecting the rate of increase of smoke concentration. When the rate exceeds a predetermined value, the rate detector causes the intensity of the smoke detector light source to increase, thereby increasing the sensitivity of the detector. In one embodiment of the invention, after the intensity of the light has been increased by the rate detector, it is maintained at the higher intensity for a predetermined time, even if the rate of increase of smoke concentration falls below the predetermined value.

Abstract: A flame detector which is capable of discriminating between hydrocarbon fires and background radiation produced by the sun, artificial light or black body radiation. Two radiation sensors are provided, each being responsive to separate known radiation peaks produced by a hydrocarbon fire. Logic circuitry is provided which produces an alarm signal only when the radiation received by each sensor is above a predetermined value, and when the radiation received by one specified sensor is greater than the radiation received by the other sensor.

Abstract: A lock for a railroad switch or the like, which comprises a housing having a socket at one end and an elongated shackle having an enlargement on one end and a recess on the other end for cooperating with locking members in the housing so as to be received in locking engagement therein. The operating member for the locking member is a rotatable and axially movable plunger. Springs are provided to bias the plunger in rotation to the locking position and forwardly. Pin and groove guide means is provided to maintain the plunger in the unlocking position and to allow the plunger to rotate to the locking position when the plunger is moved axially by insertion of the end of the shackle into the housing.

Abstract: A smoke detector system utilizing remote detectors of the photo-electric type connected to a central control panel. In one embodiment means is provided for monitoring both the signal lead and power lead, and in another embodiment, means is also provided for monitoring the condition of the detector light source. A normally illuminated compensating cell is provided in series with the smoke detection cell, with the bottom of the compensating cell being maintained a predetermined voltage above ground to provide a monitor voltage at the junction of the cells. The output signal lead is connected to the junction of the compensating cell and the smoke cell, and feeds a high impedence input amplifier, the output of which goes to the control panel. Means is provided at the panel for responding to the presence of an alarm signal on the signal lead or the absence of the monitor voltage which might be caused by a break in the signal lead, or the power lead.

Abstract: A machine for testing the sharpness of knives, particularly surgical knives, in which means is provided for grasping a cylindrical rod of material such as rubber or plastic so that a free end protrudes from the grasping mechanism, and means is provided for rotating the rod. A knife blade to be tested is mounted in a pivoted fixture which carries a predetermined weight and can be positioned so that the cutting edge of the blade rests in the side of the protruding end of the cylindrical rod. When the rod is rotated, the blade cuts into the rod, and the sharpness of the blade is determined by the number of turns required to cut through the rod.

Abstract: A package assembly for a surgical blade comprising a U-shaped member formed of resilient material such as plastic foam and a surgical blade assembled into the foam between the legs forming the U-shaped member. The foam member protects the cutting edge of the blade during packaging and subsequent handling, and the legs of the U-shaped member may be easily bent to one side to allow grasping of the blade by a blade holder to remove it from the package for use.

Abstract: A lock for a railroad switch or the like, which comprises a housing providing a socket at one end and an elongated shackle having an enlargement on one end and a recess on the other end for cooperating with locking balls in the housing socket to be received in locking engagement therein, in which the operating means for the locking balls in the housing is a rotatable member having an enlarged head disposed in a recess at the end of the housing opposite the socket end, the interior of said recess being cylindrical, the periphery of the enlarged head being sufficiently out of round to enable it to be rotated by a tool having a suitably shaped recess, yet not sufficiently out of round to be readily apparent from visual observation.

Abstract: A machine for detaching a surgical blade from a continuous strip in which it is manufactured and presenting the blade to a position for assembly into a blade holder. The disclosed embodiment of the invention is designed for use with a continuous strip of material which has blades formed integrally along an edge thereof, and joined thereto by pre-scored lines. The machine breaks the connection between an individual blade and the strip along the pre-scored lines while grasping the blade, and then moves the separated blade to a pre-determined position for assembly with a blade holder.

Abstract: A smoke detector of the photo-electric type having a photo-responsive device viewing a volume illuminated by a light beam, in which a test member is provided for being temporarily positioned in the light beam so that one side of said member is exposed to the light and the other side is in the view of the photo-responsive device.The test member has a translucent area at the forward edge which is small in relation to the cross-sectional area of the light beam. The translucent area illuminated by the beam simulates a pre-determined percentage of smoke in the beam with a high degree of accuracy since the transmission characteristics of the translucent area can be consistently maintained within production tolerances, and the exact position of the translucent area in the light beam for the smoke simulation is not critical.

Abstract: A smoke detector of the photo-electric type having a photo-responsive device viewing a volume illuminated by a light beam, in which a test member is provided for being temporarily positioned in the light beam so that one side of said member is exposed to the light and the other side is in the view of the photo-responsive device.The test member has an area near the forward edge which is thin in relation to the thickness of the rest of the test member. In one embodiment of the invention this area is thin enough to be translucent, so that the translucent area illuminated by the beam simulates a predetermined percentage of smoke in the beam with a high degree of accuracy, since the transmission characteristics of the translucent area can be consistently maintained within production tolerances, and the exact position of the translucent area in the light beam for the smoke simulation is not critical.

Abstract: A slug rejector for use with coin-operated devices, in which a pair of grippers grasp an inserted coin and move it past restraining mechanism to drop it into an entrance chute of the device. The motion of the coin past the restraining mechanism is made possible by engagement of the grippers with the protrusions of the embossed surface of the coin. In the case of a slug, having a smooth surface, the grippers cannot grasp the slug tightly enough to move it past the restraining mechanism, and consequently as the grippers move they slide off of the slug, allowing it to drop into a different chute.

Abstract: A smoke detector and housing assembly therefore in which the housing components are designed to allow rapid assembly of the detector with a minimum amount of labor. In a preferred embodiment of the invention a retainer for a photo-cell and light source is provided with a medial portion retaining the photo-cell and portions extending forwardly from the ends of the medial portion for projecting a light beam through the field of view of the photo-cell. The retainer is molded in two similar halves and fastened together after assembly of the photo-cell, light source, and other components therein.A base plate is provided with suitable apertures for receiving the forwardly projecting portions of the retainer so that after assembly they protrude from the forward face thereof. A cylindrical member and cover are mounted on the forward face of the base plate between the forwardly projecting portions of the retainer, forming a dark chamber across which the light beam projects, and into which the photo-cell views.

Abstract: A smoke detector of the type utilizing a pulsing light source and photo-responsive means producing an output signal in response to the receipt of a pulse of light from said source reflected from smoke particles and means for amplifying said output signal to produce an alarm signal, which has exceptionally low current drain so as to be adapted for being powered by a battery, and exceptional immunity to false alarms even when operated at a high sensitivity. On each pulse, the amplifier is energized and allowed to achieve a stabilized condition, prior to energizing the light source, and after the light source is energized, the amplified output signal is not allowed to create an alarm signal until the circuit has again stabilized from transients caused by the energizing of the light, thereby preventing false alarms from circuit transients resulting from internal and external causes.

Abstract: A particle detector which during periods of high ambient light is responsive to a particle concentration of a predetermined value to provide an output signal and during periods of low ambient light, is responsive to a substantially lesser particle concentration to sound an alarm.

Abstract: A smoke detector having manual means or automatic timing means for changing the sensitivity of response.

Abstract: A smoke detector operating on the reflected light principle, in which the detector housing components are designed to provide recesses in which the light and photo-cell assemblies are retained, with a slot disposed between the light and photo-cell recesses through which ambient air is drawn into a chamber illuminated by the light source and viewed by the photo-cell. When smoke is present in the incoming ambient air, it diffuses throughout the chamber to provide a large volume of illuminated smoke for viewing by the photo-cell thereby giving a fast response to the presence of a small concentration of smoke in the ambient air.The provision of the smoke inlet slot between the light and photo-cell recesses also prevents the accumulation of dust and lint therebetween which could cause a false alarm.

Abstract: A smoke detector operating on the reflected light principle, utilizing a pulsing light source and means requiring several consecutive pulses of light reflected from smoke to actuate an alarm. During normal standby operation, the light pulses at a predetermined slow rate, when smoke is present, the first pulse of light reflected from the smoke causes the time interval to the next pulse to increase, so that if smoke continues to be present, the number of reflected pulses required to actuate the alarm are received in a shorter time. The time to alarm is thereby shortened without increasing the current drain of the device and without shortening the life of the pulsing light source.