Abstract: A dual-line time recorder includes a barrel cam, printer, motor, and slide plate. The motor rotates the barrel cam. The rotational motion of the barrel cam translates into lateral movement of the printer in forward and reverse directions. A slide plate is adapted for moving the printer in a transverse direction relative to the barrel cam between a first line of print and a second line of print. After printing in a forward direction along a first line of print, the slide plate shifts the printer for printing along a second line of print in the reverse direction. After printing in a reverse direction, the slide plate shifts the printer back to its original position. The printer is fully programmable for printing a variety of data on the print medium.

Abstract: A smoke detection unit has a detection chamber for sampling smoke from a surrounding environment. The detection chamber allows air circulation but is optically opaque. This configuration is typical of photoelectric smoke detectors, for example. A housing defines a window though which air from the environment circulates into and out of the detection chamber. The window's height is approximately the same as the chamber. A cage vane is positioned in the window and is configured as an inverted frustoconical member. An inner edge of the cage vane is spaced away from the chamber. The angled vane, along the other aspects of the unit's configuration, improves sensitivity by increasing smoke circulation through the chamber. This configuration guides the air currents typically created by fires at the ceiling so that the smoke flows easily into the detection chamber.

Abstract: A smoke/fire detector assembly having a base section and a removable sensor section. The base section includes a plurality of electrical contacts and the sensor section includes a corresponding plurality of electrical contacts. Each one of the sensor section electrical contacts includes a member having a first end, extending from the sensor section, and a second end electrically connected to electrical components within the sensor section. Each one of the base section electrical contacts has: a first section having a surface adapted for mounting to a surface of the base section; a second section, having an edge common with the first section and a surface extending perpendicular to the surface of the first section; and, a pair of finger-like members, extending from a second edge of the second section. The second edge of the second section is perpendicular to the common edge. The finger-like members are laterally spaced along, and cantilevered from, the second edge of the second section.

Abstract: An emergency strobe light for warning the hearing impaired of emergency situations includes a bulb extending outwardly from a base along an axis. Reflectors extending outwardly from the base direct a high percentage of light output from the bulb along a horizontal plane and a vertical plane which intersect each other along the axis of the bulb. The strobe light draws little power and can be powered by a battery.

Abstract: In a building fire alarm system, the light strobes of a network of strobes are synchronized to flash simultaneously. Each strobe has a charging circuit to charge a capacitor which discharges through a flash tube. Once a capacitor is charged, the charging circuit is disabled. A synchronization pulse is applied through common power lines to trigger discharge of each strobe capacitor through the flash tube followed by recharging of the capacitor.

Abstract: A fire alarm system automatically adjusts sensitivity of individual sensors based on evaluation of background level over a period of time. High sensor signals which do not trigger a fire alarm may, after a delay time, result in decreased sensitivity to avoid false alarms. On the other hand, low peak values stored over a period on the order of months result in an automatic increase in sensitivity of the system. The sensitivity is adjusted by changing the delta threshold of an alarm threshold over a quiescent sensor signal average.

Abstract: A time recorder stores on and off times of technician repair jobs and receives repair order numbers and flat rate times through a key pad input. The time recorder prints flag tickets on adhesive-backed paper for application to repair orders. The system also prints daily time cards and efficiency in progress reports when requested by a supervisor. Technicians are identified to the time recorder by key pad input or by a bar code wand and supervisors are identified through key pad input or badges having magnetic stripes.

Abstract: An electronic heat detector provides a fire alarm with a rapid rate of rise of temperature. The rate of rise indication is obtained from a comparison of outputs from a first temperature sensor which responds rapidly to environmental temperature, referenced to a second temperature sensor which has an intermediate response between that of the first sensor and an electronics board. The second sensor is positioned within a protuberance from the heat detector housing.

Abstract: A method and apparatus multiplexing multiple alarm and head type values in a peripheral fire alarm device includes a head component for sensing the presence or absence of smoke or heat and a base component for communicating with the control panel. A communication interface between the base and head components with no more than three connectors for multiplexing the values between the head component and the base component. The control panel stores algorithms particular to each type of head which may be used to determine if an alarm condition exists. Using data received from the peripheral fire alarm device, the control determines which type of head component is currently installed at the base component and selects the correct algorithm.

Abstract: A monitor/control communication net with intelligent peripherals, that is, peripherals which are capable of monitoring and/or controlling various devices in accordance with messages received from a central panel cpu and which are also capable of reporting to the central panel the status of one or more devices monitored by the peripheral. Each peripheral is assigned a unique address by which it is polled by the central panel. All communication messages between the central panel and peripherals include a format code which indicates the nature of the message and the length of any data field in the message. Communication time is minimized by permitting the data field to vary in length from one peripheral to another, depending on the number and type of devices being monitored and/or controlled by the peripherals.

Abstract: Walk through test system for testing devices such as pull stations, smoke detectors, alarm bells and the like for alarm and trouble conditions without the assistance of a central panel operator. The devices are connected in a loop or loops distributed throughout one or more zones remote from a central panel. Alarm and trouble conditions are detected at the central panel. When a device is placed in alarm by the workman, a coded alarm is sounded which is aurally detectable by the workman at the location of the device, remote from the central panel. The coded alarm identifies the zone loop in which the device is connected. When a trouble condition is created in a loop by the workman, an alarm is sounded which is aurally detectable at the location of the loop, remote from the central panel. The alarm is coded to indicate to the workman that a trouble condition has been detected at the central panel.

Abstract: A time card carrier has means for alterably storing employee identification, time and attendance data, and means for releasably retaining an employee time card having an imprintable portion. The time card has an extended tab portion for proper orientation of the card on the carrier. The time card carrier is reusable to allow a fresh time card to be inserted onto the time card carrier at the beginning of each new payroll period.

Abstract: A single piece trigger and knock off mechanism for a switch operated card printer includes a lever integrally connected to a resilient mounting bracket which provides a first flexural pivot. The lever comprises a pair of integrally connected arms, each provided with an ear. A moving card contacts the ear on one arm, causing the lever to swing about the first flexural pivot. As the lever swings, the ear on the other arm contacts a switch which triggers a card printer solenoid. The solenoid operates a card printer hammer. The card printer hammer is driven towards the card when the solenoid is triggered. As the hammer is driven towards the card, a moveable element associated with the card printer strikes the arm whose ear is in contact with the switch, causing the arm to swing about a second flexural pivot formed by a bend in the arm. As the arm swings, the ear releases the switch. This knocks off the solenoid just before the hammer contacts the card.