Abstract: An electric indicator that includes an indicating light mounted in a small case containing electronic circuitry, a numerical keyboard, and a battery, the case being attached to a door or door frame, to show the returning user of the indicator whether or not the door has been opened since the indicator was last enabled by the user, typically by entering a secret sequence of numbers into the keyboard. An auxiliary input jack, for electrical connection to other doors and windows, is provided so that the indicator can indicate whether any of several doors and windows has been opened. An auxiliary output jack is provided for a remote indicating light, usually inserted into the peephole existing in many front doors so that the indicator light may be seen from the outside before opening the door. The same output jack may be used for triggering separate audible alarm devices. The indicator is easily adapted for use with drawers, bins, or windows if so desired.

Abstract: An electrical arrangement for a handbag including a switch unit having at least one electrical terminal on its exterior, a magnetically resposive switch in its interior connected to the terminal, and a battery in the handbag connected to the terminal and to the magnetically responsive switch. The terminal is adapted to receive either an illumination device or an alarm device at the option of the handbag owner. A magnet is utilized in conjunction with my novel switch unit, with the switch unit being mounted on one interior wall of the handbag, and the magnet being mounted on another interior wall of the handbag in a position opposite, and in substantial alignment with, the switch unit. The magnet is supportable in at least two different positions on its mounting such that when in a first position it can interact with the magnetically responsive switch as the handbag is opened or closed, thus causing the illumination of a bulb or sounding of the alarm as the handbag is opened.

Abstract: A cover for a fill pipe opening of an underground fuel tank which contains a transmitter which will be activated when the cover is disturbed to transmit an alarm signal to a remote location. The signaling equipment is fully contained within the cover and the cover is sealed to protect the equipment from contamination. A rechargeable power source such as a battery is also contained within the cover, and it can be charged without breaking the sealed cover. The cover can be used in place of the existing cover without any modification to the fill line or fill access opening.

Abstract: An intrusion detecting switch is disclosed having an operator and a sensing device for sensing the detection of intrusions and to a protected area. The operator may be a magnet and the sensing device may be Hall effect switches the resistance of which will switch between high and low values in the presence and absence of the magnetic field. A mounting device may be provided for mounting the housing containing either the sensing device or the operator to its support. The mounting device is located behind the operator or sensing device such that if the housing is to be removed from its support, the sensing device or operator must be first removed which will result in an alarm.

Abstract: There is provided an alarm, which includes a mounting base, and means for securing the mounting base to an item whose movement is to be signalled by the alarm. A magnetic reed switch constitutes a first element, and a magnet constitutes a second element. One of these elements is mounted on a pivotal member capable of pivoting with respect to the mounting base, while the other of the elements is capable of retaining a given position with respect to the mounting base.

Abstract: A container for an alarm transmitter used in combination with components of a transmitter circuitry which includes voltage control for providing a gated voltage and controlled by a timing circuit. The components also include an audio multivibrator which is electrically coupled to the voltage control in order to receive the gated voltage, a microfork audio filter which is electrically coupled to the audio multivibrator and a modulator which is electrically coupled to the audio multivibrator. The components further include a radio frequency oscillator whose frequency is modulated by the modulator and which has an antenna electrically coupled to its output terminal. The container includes a tubular member which is adapted to be installed into a hole in a wall adjacent to a door or a window and an elongated, rectangular member adapted to be inserted into the tubular member and also adapted to have the components of the transmitter circuitry placed thereon.

Abstract: A security device for protecting premises having three separate variable time delays. A first time delays allows a legitimate user of the device to enter the premises and de-activate the device before the alarm sounds. The second time delay permits a legitimate user to exit from the premises without sounding the alarm. The third time delay ensures that the alarm will sound for a minimum period once the loop has been opened by an intruder. The device has an integrated circuit and each of the time delays are achieved through the use of a resistor in combination with a capacitor. The device also has a supervisory loop and the alarm becomes activated when the loop has been opened.

Abstract: An intrusion alarm is provided in a compact enclosure permitting its movement from location to location as needed. The alarm includes one or more motion detectors, some of which may be battery operated, one or more alarm devices, such as horns, sirens, etc., door switches and appropriate relays for operating the system. A battery back up system insures that the alarm is always activated.

Abstract: An alarm system signals an attempt at intrusion through an opening framed to receive first and second panel members movable between opening and closing positions, as specifically shown in the form of a sliding glass door and screen door combination. An electrical switch mounted upon one panel has an element responsive to a magnetic field for developing a signal. A magnet mounted upon the other panel is productive of a magnetic field that interacts with the element of the switch upon movement of both the first and second panels to their closed positions. A signaling device coupled to the switch yields an alarm indication upon the beginning of the movement of either one of the panel members away from its closed position.

Abstract: Matching components of a magnetic locking assembly are magnetically attracted into mating relationship until a predetermined magnetic flux is established in one of the components. Such established predetermined flux is monitored to detect locking power diminutions between the locking assembly components. External magnetic fields applied to the locking assembly in an attempt to counterfeit the mentioned predetermined magnetic flux may be detected and indicated for security reasons.

Abstract: A protective barrier and burglar alarm in the form of a window blind includes a plurality of slats which may be compacted to open the blind, the slats being supported by flexible cords including electrical conductors establishing an electrically-conductive pathway through the length of the window blind. The lower end of the blind carries retaining means for retaining the blind in its closed position, and circuit-interrupting means effective when the blind is raised or severed to actuate an alarm. In one described embodiment, the retaining means and circuit interrupting means include mating pins and sockets; and in a second described embodiment, they include magnetic retainer elements adapted to actuate a magnetic reed switch carried at the lower end of the blind.

Abstract: A portable alarm device senses movement of the device and actuates an alarm. A pendulum with attached magnet, set in motion by movement of the device, causes closing of alarm circuit reed switches to actuate a continuous alarm. The pendulum may be set by a control member and removable key to a hold position to prevent its oscillation or to a release position to allow its oscillation.

Abstract: A security device adapted for use with a slidable-type window or the like basically comprises a two-part electrical contact switch, one switch part being mounted on the molding surrounding the window frame and being electrically connectible to an alarm system, and the other switch part being slidably associated with a longitudinal bracket mounted on the window frame adjacent the first switch part. The window frame can be slid open or closed, without activation of the alarm system, by holding the two switch parts in electrical contact with each other.

Abstract: In an alarm control system for protecting a premises, a four conductor bus line leading from a master control station is extended about the interior perimeter of the premises. Sensors positioned near each port of entry to be monitored are connected in parallel relationship to the bus line, as is at least one remote station for manually arming, disarming or activating the system. Each sensor comprises a biased reel carrying line secured to window, door, screen, or the like. Disturbance of a sensor causes a magnetically responsive switch therein to generate a pulse triggering circuitry within the control station to activate the desired alarm device for a predetermined period of time. The system then resets automatically to an armed or ready condition to continue protecting the premises against subsequent intrusions. Preferably, the lines in the sensors are of a thermoplastic material so that the system is also activated by abnormally high temperature in the event of fire.

Abstract: The device includes a housing, a keyboard on the housing, and a loudspeaker and electric components within the housing. The housing is mounted on a door adjacent a magnet mounted on the door frame. The device includes an audio alarm circuit including a loudspeaker for generating an audio alarm, a control circuit coupled to the alarm circuit for controlling operation of the alarm circuit, and signal generating curcuitry including door motion sensing logic for sensing when the door has been opened and for generating an alarm signal which is applied to the control circuit for operating the alarm circuit. The device further includes a programmable alarm inhibiting circuit including the keyboard which comprises a plurality of keys and pushbutton switches operated by the keys. The alarm inhibiting circuit includes keyboard decoding logic. A code setting circuit includes three leads which are coupled to the keyboard decoding logic and which are releasably connected to one side of the pushbutton switches.

Abstract: A lock for the door of an automobile which is provided with an electrical signalling circuit for indicating to the driver whether the lock is opened, partially closed, or fully closed. The lock has a main supporting body. A movable member is held on the body and assumes a first position when the lock is closed, a second position when the lock is partially closed and a third position when the lock is open. The lock also includes a magnet switch which is connected in the electrical signalling circuit. A projection is connected with the movable member such that when the movable member is in the first position at which the lock is fully closed, the projection is interposed between the reed relay and the permanent magnet and this interrupts the magnetic flux lines between the magnet and the reed relay contacts, causing the contacts to open and opening the electrical signalling circuit.

Abstract: A magnet and one or more magnetic field responsive switches, preferably Hall effect sensors, are respectively mounted in alignment on opposing edges of a two door refrigerator in one preferred embodiment. Movement out of alignment of either the magnet or switch generates a door ajar signal to activate visual and/or audio alarms. Embodiments employing mono-polar and bipolar Hall effect sensors are shown. A single door embodiment is shown with the magnet held in a fixed position opposite the sensor mounted on the door edge.

Abstract: An alarm actuating roller shutter of interconnected armor links is disposed for movement within a pair of opposed guide rails each of which has an outer cross sectional chamber partitioned off from a guide cross sectional chamber. The alarm is actuated by a magnetic switch consisting of a magnetic actuator portion on at least one of the armor links and a stationary switch portion within the outer cross sectional chamber. The actuator and stationary switch portion are arranged so that the actuator portion will actuate the stationary switch portion when the roller shutter is in the closed position.

Abstract: An intrusion sensor circuit for protecting building openings having at least one moveable closure member, the sensor circuit including a magnet and a pair of magnetically operated switches mounted on the building opening and/or the moveable closure member therefor, the magnetic switches being commonly moveable relative to said magnet. An alarm circuit connected to the magnetically operated switches transmits an alarm signal to a receiving or monitoring station upon movement of the closure member a selected distance relative to the building opening when the circuit is armed. The pair of magnetic switches are positioned a short selected distance from each other, the first of the switches being positioned opposite a permanent magnet member on either the moveable closure member or the building opening and the first magnetic switch is adjacent thereto when the opening is closed.

Abstract: A burglar alarm that has a series of switches located close to each other and that are responsive to the application of a magnetic field. One of the switches terminates current flow to a sentinel current device while the others initiate current flow to the sentinel current device. The sentinel current device operates to supply voltage for an alarm circuit when it conducts only. Thus, in order to render the device ineffective, one must know how to apply a magnetic field to the terminating switch only without activating any of the switches that initiate current flow. The switches are all located close together so that special knowledge is required to cut off supply voltage to the alarm circuit.

Abstract: A normally-open magnetic reed switch is mounted on the bottom of a venetian blind or similar barrier and a magnet is mounted in the window sill to hold the switch closed when the barrier is in its normal position. When closed, the switch shorts a timing capacitor in an associated alarm circuit. If the switch moves away from the magnet (thus allowing the switch to open) long enough for the timing capacitor to charge, an alarm signal is produced. Thus an alarm will not be produced by trivial movements of the barrier.