Abstract: Magnetic key and barrel device wherein the magnets (8) of the key (1) cooperate by repulsion with magnets (25-225) embedded into bascule elements (21-221) movable between a locking position of the lock and an operating position wherein the bascule elements release the rotor-stator interface. The rod (7) of the key (1) is configured as a tube in the wall of which are embedded the magnets (8), and the rotor is configured as a sleeve (14) in the wall of which are arranged the bascule elements (21 and 221). The sleeve (14) has in its center a cylindrical ferrous core (17) which permanently attracts the magnets (25 and 225). The stator (3) which surrounds the rotor (2) is drilled with ports (26 and 226) wherein the magnet-free bascule (21 and 221) ends are sunk. Application to any locking and control lock.

Abstract: A magnetic lock which may serve, itself, as a locking device, or may form part of an otherwise conventional locking device, is provided with a body member, detent balls, and a detent locking plunger that is disposed in an axially extending interior space of the body member in a manner enabling the locking plunger to be displaced within the body member between a first location, at which the locking plunger causes the detent balls to be locked in a position protruding from the body member, and a second location at which the locking plunger enables the detent balls to retract into the body member. The body member is provided with a sealed end having a key seat upon which a key may be seated for shifting the locking plunger between its first and second locations.

Abstract: In a cylinder for locks having an outer barrel and an inner cam with a keyhole. In order to lock the movement of the inner cam, a pin is provided in the outer barrel and the pin is engaged into a hole defined in the inner cam to lock the inner cam. The pin is urged by a spring so as to eject the pin from the hole and the pin is inserted into the hole by a driving mechanism utilizing a manual force. The engaging state of the pin with respect to the hole is held by a hold mechanism without any electric power consumption. The hold mechanism is responsive to an electric signal to release the engaging state between the pin and the hole.

Abstract: A number of bearers concurrently use card-keys, having a common access code, and a unique lockout code to open a single lock. If a particular bearer is to be selectively locked out, the lockout code sensing device in the lock is changed to lockout the particular bearer but not all other bearers concurrently using their card keys to open the same lock.

Abstract: A closure lock system comprising a lock assembly, a lock actuator for locking or unlocking the lock assembly and a lock circuit including a reed switch which when closed by a magnet of a key causes the lock actuator to lock the lock assembly.

Abstract: Safety mechanism for locks (electronic lock) comprising a pick-up performing the function of a key and a sensor performing the function of a lock part. The pick-up is provided with a pre-determined surface arrangement of magnetically permeable, preferably inactive material in the form of soft-iron pins forming exciting elements, which forms a code. For detecting the code of the pick-up, the sensor is provided with an arrangement of sensor elements in a surface matrix of the same geometrical extension, which sensor elements can be varied as to their ohmic resistance by a change in the distribution of the magnetic field lines and take the form of magnetically controllable magneto-resistors. The magneto-resistors are set up, preferably, in the manner of an integrated circuit.

Abstract: The invention concerns a system for the unsupervised control of the use of lockers or the like in bath houses, reading rooms, hotels or the like in which the locker doors are provided with a deposit lock; in order to optimize the possibilities of variation while retaining the most favorable structural shape, the locks are operated with codes such that the deposit locks can be brought into the position of readiness to receive a code and store the code and the memory is automatically erased upon the return of the deposit coin.

Abstract: A device is provided, designed to prevent unauthorized operation of fire hydrants by completely concealing the hydrant operating nut and weather shield within freely rotating sleeves, thereby rendering the hydrant inoperable. The hydrant is made operable by the use of a specially designed self-contained magnetic operating wrench. The hydrant again becomes inoperable when the magnetic wrench is disengaged. The device is externally mounted for easy, quick field installation with common tools, and requires no modification of the internal hydrant mechanism. The device is designed to be used on all hydrant makes and models having an operating nut extending vertically above the hydrant bonnet.

Abstract: An electronic locking system including a lock cylinder having an electronically actuable release assembly which is selectively enabled to disengage a pin from a cylinder plug, to permit the rotation of the plug by an inserted key. The lock cylinder and key each contain non-volatile, electronically alterable memory devices, such as EEPROM integrated circuits, which house keying system codes. The key EEPROM is preferably housed within the key blade, in a key design which closely resembles a traditional mechanical key without the usual bitting. The release mechanism incorporates a locking pin which is moveable between plug-engaging and non-engaging positions, along a radius of the lock cylinder. The release mechanism may include a primary actuator which directly moves the locking pin, or may act indirectly upon the locking pin via a latching member.

Abstract: A center locking device of intermediary plate type for a disc wheel of motor vehicle. The device has a cap nut screwed onto a threaded section of a flange fixed to the axle of the disc wheel. The disc wheel is clamped between the cap nut and the flange. A locking device is provided to lock the cap nut to the threaded section of the flange for preventing the disc wheel from becoming loose and/or theft of the disc wheel.

Abstract: A rotatable magnetic tumbler apparatus for a magnetic lock comprises at least one rotatable magnetic tumbler, whose rotary orientation is adjustable by a magnetic key corresponding to a preselected magnetic code, and which is contactable by a contacting element of the lock. The rotatable magnetic tumbler is movable in the direction of the rotation axis of the tumbler, and the contacting element is suitably mounted in the magnetic lock for making contact with the rotatable magnetic tumbler in a predetermined position on the rotation axis.

Abstract: The lock housing has a slot in a top wall via which a coded card key can be inserted to bring into alignment coded magnetic areas on the card with magnetically responsive elements of the lock to unlock the locking mechanism and enable rotation of either a knob or lever arm to open the door. The card moves a spring actuator against a coupling spline to engage it with a spindle spline carried by a shaft interconnected with the knob or lever arm handle. The sliding coupling spline is integral with parts which interrelate with the door lock mechanism such that rotation of the knob or lever arm will now effect release of the door locking mechanism. When the card is fully inserted, the mechanism is maintained in the unlocked condition and the card may be released to turn the knob or handle with the same hand. Spring-loaded members separate the coupling and spindle splines as the magnetic card key is withdrawn from the housing slot.

Abstract: A lock cylinder comprises a cylinder housing and a cylinder core having at least one rotatable magnetic tumbler supported therein, in which at least one axially slidable locking element is provided. The locking element has projections thereon directed toward the exterior. The locking element has a contacting slider having contacting elements projecting toward the rotatable magnetic tumblers, and a locking slider engaged with and fit together with the contacting slider, on which are mounted the projections. The lock cylinder is also provided with a pressing member fixed with respect to the cylinder housing, by which the locking element in the O-position of the cylindrical core is held against the force of a compressible spring engaged to the locking element, and is pushed into an unlocking position on rotation of the cylindrical core.

Abstract: The lock cylinder comprises a cylinder housing and a cylinder core having at least one rotatable magnetic tumbler supported therein, wherein in the cylinder core at least one axially slidable bolt member is provided, whose slidability is controlled by the rotatable magnetic tumblers. The bolt member has two control tips positioned at opposite ends thereof, which are guided with two control surfaces mounted, so as to be nonrotatable with respect to the cylinder housing and positioned opposing each other. Thus a positively actuated control of the bolt member is provided, which is independent of the sliding force, which would be provided by a spring. One of the control tips is slidable against an elastic restoring force, whereby, after a certain limiting force has been exceeded, a relative displacement between the control surfaces of the bolt member occurs so that a subsequent rotation of the cylinder core without collateral axial displacement of the bolt member is made possible.

Abstract: A magnetic lock is provided which has a housing carrying a rotatable core with magnetic rotors and an axially displaceable lock bar which is rotationally connected to the core. A catch ring is provided with means engagable with the lock bar to drive the lock bar axially away from an initial position upon rotation of the core, and a return ring is provided with means engagable with the lock bar to drive the lock bar axially toward the initial position upon a further rotation of the core.

Abstract: An electric lock comprising a solenoid which has a permanent magnet for attracting a plunger and an electromagnetic coil which is positioned adjacent the permanent magnet so as to control the magnetic flux of the permanent magnet. A cam member which has a cam surface formed at one end thereof engages an engaging pin when a bolt operating member is rotated so as to lock the electric lock so that an engaging rod is forced to move in the direction opposite to the direction in which an engaging bolt is biased, the other end of the engaging rod being connected to the plunger of the solenoid. A positive voltage application unit responds to an unlocking signal so as to temporarily cause a current to flow through the electromagnetic coil in such a way that the flux produced by the electromagnetic coil cancels the magnetic flux produced by the permanent magnet.

Abstract: A door lock in which the lock bolt is not retracted by direct action of the handles but is instead retracted by slide members acted upon by the handles, the slide members having means for engaging a further slide which carries the bolt. One of the engagement means includes an electromagnet and an engagement member. The engagement member engages the bolt carrying slide only when the electromagnet is energized, which occurs when an appropriate key has been inserted into the lock and verified.

Abstract: A first set of pivoted latching fingers having hook ends facing in a first direction are provided, together with a second set of pivoted latching fingers interlaced with the first set in accordance with a particular combination which unlocks the device. The fingers of the second set of latching fingers have hook ends facing in a direction opposite to the direction of orientation of the hook ends of the first set and actuation of only the proper combination of fingers causes the hooks of all fingers to be displaced away from a pair of facing lock anchor members to unlock the lock. All of the fingers are pivoted so that slight amounts of magnetically permeable material in the card key are sufficient to move the hooks of the pivoted latching fingers bearing permanent magnets, through a substantial distance, to enable the use of a thin, flexible card key for positive lock actuation.

Abstract: For an electronically motivated door lock there is a key carrying magnetic coding for actuating an electronically triggered release mechanism to unlock a door. Insertion of the key in the keyway initially closes a switch to energize the electronic circuit. The electronic circuit is programmed to motivate a motor driven mechanism in successive stages to move a blocking finger into and out of engagement with a notch in a rotatable disc on a cylinder plug which operates the latch bolt. The motor rotates preferably in one direction but by use of a rotating drive pin shiftable from end to end of a transverse slot, the blocking finger is moved alternately into and out of engagement with the notch in response to the successive energizations of the motor.

Abstract: A lock for operation by a magnetic key has some locking elements which are moved circumferentially from locking to releasing positions by the key and further locking elements which are moved axially by the key from locking to releasing positions.

Abstract: In a locking system, a combination of mechanical tumblers which are moved into a release position by the shape of the key and at least one magnetic tumbler which is drawn into the release position by a visually nondiscernible magnet placed on the key. The lock style being standard in that it includes inner and outer cylinders wherein the inner cylinder rotates between an open and locked position. In an alternate embodiment of the subject invention, an additional tumbler made from a magnetically attractible material is placed in the cylinders and biased to the open position. Should the key being used to open the lock contain a magnet substantially adjacent to this additional magnetic tumbler, the tumbler will be drawn to the locked position thereby preventing the rotation and opening of the inner cylinder.

Abstract: A special type of key is made use of to actuate an electronically triggered release mechanism to unlock a door. To enable the electronic means to function, insertion of the key in the keyway initially closes a switch to energize the electronic circuit. Also when the key reaches the switch closing position, a read head for the electronic circuit, located adjacent the keyway, interprets magnetic coding carried by the key. The electronic circuit is programmed to motivate a motor driven mechanism to move a locking pin out of engagement with a latch bolt where the latch bolt has been acting to hold a door locked. Once the locking pin has been removed, the latch bolt is in fact withdrawn from its locked position by rotation of the key in a substantially normal fashion.

Abstract: In a magnetic locking system for locking a door to a fixed member, comprising a key cylinder connected to the door, a magnetic sensor connected to the door near the key and operating when sensing a predetermined magnetic force, control means for locking the door to the fixed member when the magnetic sensor operates, and a magnet-mounted key including a key cylinder proper which is to be engaged with the key cylinder and a key head which is equipped with an elongate magnet piece, there is proposed an arrangement in which when the key is operatively engaged with the key cylinder to turn same, an imaginary plane which the axis of the magnet piece describes when the key turns about the axis of the key cylinder intersects the axis of the magnetic sensor.

Abstract: Two control rings (29a, 29b) are arranged between the cylinder (2) and lock body (1) which are provided with latch grooves (9) receiving that part of the latch (8) which prevents cylinder (2) rotating. The rotor housing has a latch channel (11) formed along the chord of the magnetic body (5) in the rotor (6) and can receive the other part of the latch (8) in a state of magnetic equilibrium determined by the magnets in the key (3) and the magnetic body (5). When a proper key (3) is fitted into the keyhole (10), the latch channel (11) is arranged partly in the rotor (6) housing and partly in the rotor support (4): in this position the cylinder is freely rotatable. When the proper key (3) is removed, the latch channel (11) in the rotor housing is outside the line of action of the latch (8), the latch (8) being arranged in the rotor support (4) and in the latch grooves (9) of the control rings (29a, 29b).

Abstract: A wheel locking device is a locking means wherein one of a plurality of fastening nuts with which a wheel plate covering both the inner face part of a vehicle tire and the external face of a wheel is secured to the wheel by a lockable nut which cannot be removed without using a key.

Abstract: The locking system comprises a magnetic key having a plurality of parallel rows of magnets arranged in a pattern one behind the other and forming a locking code of the magnetic key, and a reading device into which the magnetic key can be inserted in the direction of the rows of its magnets. The reading device comprises magnetic field sensors for the serial reading of the locking code formed by the magnets. A control circuit which compares the information of the read locking code with the information of a predetermined locking code generates a control signal in dependence upon the conformity or difference of the locking codes. At least the magnets of the pattern positions of each row which are immediately adjacent in the row direction are oppositely polarized.

Abstract: An electronic lock system senses codes on a key by means of opto-electronic, magnetic or other electrical means and compares the key code to a code stored internally in a memory. When the key code is equal to its respective stored code the lock activates an electrical clutch operated bolt, and may also change the internal code to a new code.This invention relates to electronic locks, and is more particularly directed to the provision of an electronic lock which can be operated by a key having a code in the form of an electric parameter or optical parameter thereon.

Abstract: The publication relates to a lock system of the type which may be activated and/or recoded by means of a preferably plate formed key and/or recoding unit. The publication relates also to a method for recoding such system and to a key member for recoding the system. The lock system comprises a reading unit reading the code on the key and/or recoding unit, a unit comparing and memorizing the detected code and means for activating the mechanical parts of the lock thereby suspending its locking effect. The purpose of the system is to enable recoding of lock independent of a priority determined sequence of codes on the key and without being dependent of a centrally arranged memorizing unit, memorizing the various codes in sequence. The proposed effects are achieved by including a code section on the key member on to which a recoding command may be recorded.

Abstract: A closure device has a cylinder core turnable in a housing and a key insertable into a key channel in the core. A ball provided in a circumferential groove in the inner wall of the housing cooperates with an edge portion of the key. A pin is arranged in the same plane and 180.degree. away from the ball.

Abstract: A cylinder lock-key combination includes a cylinder housing (1) having arranged therein a rotatable cylinder plug (2) having a slot (3) for a key (8). Arranged on the spine of the key is coded information in the form of regions (8a, 8b) of mutually different magnetic permeability. When the key moves relative to the housing these regions cause variations in a magnetic flux generated by a magnetic body (5k) and passing the key slot (3). A differential field plate (5) arranged in the housing and incorporated in an electric circuit, which also incorporates a bridge coupling, is arranged to convert said magnetic flux variations to momentary changes in resistance in the electric circuit, causing the bridge coupling to become unbalanced so that an electric pulse train corresponding to the coded information is generated in the circuit. This pulse train is sensed and evaluated by means, for example, of a data processing device. The invention also relates to a cylinder lock and a key for said combination.

Abstract: A lock for operation by a magnetic key has a magnetic locking element (47) which moves in aligned, longitudinal grooves formed in inner (10) and outer (18) members of the lock. When the locking element is aligned with a transverse channel (57) in the inner member, limited relative rotation of the members can occur.

Abstract: A combination lock is disclosed which employs magnetic forces to rotate the tumblers in unison when not being urged by aligning means. The aligning means are pins on the tumblers and abutment surfaces in the front and back plates of the lock so that the combination can be dialed without the necessity of rotating the tumblers through a complete 360.degree..

Abstract: A package comprises a cover closing an article housing formed in a baseplate. A contiguous compartment closed by a plate contains a spring assembly comprising two arc members joined at their ends and bearing on abutment members. A profiled rod inserted through a complementarily profiled opening pushes on thrust member against the abutment of the ends of the spring assembly on the abutment members so as to bring about, by symmetrical reaction, retraction of the bar supporting the bolt members. However, if a fly-weight has not previously been retracted by a magnetic field a projection engages in a groove in the fly-weight to lock the lock. The consecutive action of the magnetic field and the pressure on thrust member are applied by a key device retained at the checkout of the self-service store. The invention has one particular application in the merchandizing of prerecorded magnetic tape cassettes.

Abstract: A control device for a magnetic cylindrical lock having a cylindrical housing and a cylindrical plug disposed for rotational and axial movements in the housing, comprises a longitudinal bore in the plug, magnetic rotary members arranged for rotation across the longitudinal bore, and arresting means for blocking the rotation of the plug in one axial position of the latter and for permitting the rotary movement in another axial position.

Abstract: A locking and release mechanism includes two interlocked members, and two detents which hold the two interlocked members together. One of the two detents is magnetically operated and the other is mechanically operated. The mechanically operated detent involves the use of a mechanical operating member which moves through a channel, and an additional movable magnetic element which selectively blocks the channel. A special release member, which may be thought of as a key, carries both the mechanical member for extending through the channel and two magnets for operating the magnetically-operated detent, and the movable blocking member for the mechanically operated latch.

Abstract: A magneto-electronic lock includes a key body having a magnetic combination. In the interior of a receiver of the key body are arranged magnetic detectors, a bolt, and an electronic circuit device connected between the bolt and the detectors. Positive and negative magnetization devices cooperate, depending on the position thereof, in opening, closing or blocking an electronic circuit including an electric opening pulse of a gate. A device determines the electric continuity both in the key and in the receiver thereof. An electric derivation device opens a code. Passive positive and negative relays are in combination with positive and negative magnetic elements. Positive and negative magnetic devices have potentials to act on the passive relays in the contact threshold.

Abstract: A key-operated lock, which comprises a reading head with a Hall generator, whereby the key is provided with magnetically readable data locations each of which forms at least a dual code. Between the individual data locations, magnetically readable time pulse planes are located. The data locations are represented by coded segments of soft magnetic material or permanent magnets. The timing pulse planes are either represented by these coded segments or are identified by the Hall generator in that the inductance between successive data locations drops to a value close to zero without rendering necessary any coded segments. Furthermore, circuits are described for analyzing the signal voltages supplied by the Hall generator for receiving clear signals or blocking signals for the lock.

Abstract: A card operable magnetic lock apparatus comprising an elongated non-magnetic plate member and a plurality of tumbler members which are normally biased into engagement in longitudinally spaced recesses of the plate member to prevent longitudinal movement thereof. The tumbler members pivot about a common axis and have north and south magnetic poles which are substantially opposite relative to the axis. A properly encoded magnetic card can be positioned adjacent the tumbler members to urge the tumbler members out of engagement in the recesses to free the plate member for longitudinal movement.

Abstract: A lock device comprising a fixed cylindrical member, a rotatable member fitted into said fixed member and rotated to cause a dead bolt to be reciprocated and having a key hole extending along the axial center line thereof, and a means for locking said fixed member to said rotatable member by a plurality of permanent magnets arranged according to a predetermined pole pattern, wherein said locking means can be released so as to enable the lock device to be locked and unlocked when a key having a plurality of permanent magnets embedded on both sides thereof according to the predetermined pole pattern is inserted into the key hole, characterized by a fixed guide cylinder rotatably housed in said fixed member, an engaging means for fixing the fixed guide cylinder to said fixed member and releasing the fixed guide cylinder from said fixed member, a pattern reading means for detecting the pole pattern of said key, and a driving means for driving said engaging means to fix said fixed guide cylinder to the fixed membe

Abstract: The present invention relates to a magnetic tumbler cylinder lock mechanism having enhanced safety because of a key disengagement preventive device that prevents the key from disengagement from the key hole when the lock mechanism is in the fully locked or fully unlocked position.

Abstract: A magnetic locking device for a door comprises a latch slidable from a locking position to an unlocking position and vice versa, a locking element provided with a number of webs and slidably mounted within the latch for moving the latch between the locking and unlocking position, and a number of magnetic rotors in the latch. Each magnetic rotor is formed with a recess in which the respective web of the locking element is engageable when the latch is moved from the locking position to the unlocking position. The magnetic locking device is further provided with a blocking element engageable with the locking element in the locking position and unlocking position.

Abstract: A magnetically locked fluid valve having a particular utility in a fire hydrant to prevent unauthorized usage thereof. The fire hydrant includes an operating nut mounted on top of one end of a hydrant actuator shaft, and a magnetic lock is located in immediate proximity thereto. A shaped magnet is adapted to be placed around the actuator shaft adjacent to the magnetic lock, after which a wrench can be applied to the operating nut to control operation of the fire hydrant. The magnetic lock includes magnetic tumblers which are shifted in position in response to placement of the magnet on the actuator shaft. The actuator shaft includes an upper section coupled to the operating nut and a lower section coupled to the hydrant valve. The magnetic lock is positioned between the upper and lower shaft sections, and the upper shaft section is freely rotatable relative to the lower section when the magnet is removed, but is locked relative thereto when the magnet is positioned thereon.

Abstract: A magnetic lock wherein the movable portion is sandwiched between two stationary portions. The movable portion carries a plurality of transversely slidably movable magnets which serve as pin tumblers that fit into recesses or cavities in either stationary part to lock the movable member against movement. Fixed to one of the stationary parts are means for biasing the pin tumbler magnets toward the other stationary part whereby to hold the lock in unlocked condition. The key is placed adjacent the other stationary part and carries magnets poled to repel the pin tumbler magnets with an equal and opposite force to the biasing means to locate the pin tumblers wholly within the movable part so that the movable part may be moved. Preferably, at least two of the biasing means have different strengths for biasing the pin tumbler magnets.

Abstract: The invention relates to a magnetic tumbler lock comprising an inner cylinder adapted to turn in an external housing, said inner cylinder having a keyhole for receiving a key, locking means including at least one magnetic tumbler, which is adapted to rotate about a rotary axis extending substantially transversely of the longitudinal axis of the inner cylinder, and a key which is provided with a magnet for co-operating with the magnetic tumbler causing the magnetic tumbler to rotate into an unlocked position when the key is inserted into the lock.

Abstract: An anti-theft device for a vehicle having an internal combustion engine provided with an electrical circuit constituting an ignition or engine-heating circuit. The device includes a first circuit member having an output, a second circuit member having an input, the first and second circuit members being parts of the electrical circuit. A plurality of magnetic switches are disposed in a housing. One or more of the magnetic switches are electrically connected in series between the output of the first circuit member and the input of the second circuit member, all remaining ones of magnetic switches are connected between the input of said second circuit member or the output of the first circuit member and ground of the electrical circuit. One or more magnets are carried on a support in the form of a key which can be inserted into a slot in the housing.

Abstract: A mechanical magnetic key operated door lock structure particularly adapted for use in hotel locksets. An occupancy indicator is incorporated in the lock structure to indicate that the lockset is locked from the inside, thus insuring privacy for the hotel guest. In addition, means operable from outside the lock structure is provided for changing the combination of the lock so that a newly arriving guest may be provided with a key having a different combination from that used by the previous guest.

Abstract: A lock comprises a cylindrical case with a turnable member rotatably mounted therein. A latch member is also rotatably mounted in the case. The latch member is rotatable in a first direction to lock the lock and in an opposite second direction to unlock the lock. A drive member is co-rotatably mounted in the case between and with the turnable member and the latch member. At least one magnetically attractable tumbler is movably mounted on the interior of the turnable member and has a portion which projects into engagement with a receiving cavity of the drive member when the lock is in an unlocked position. This permits the drive member to move axially away from the latch so that rotation of the drive member to rotate the latch to an unlocked position will release the latch.

Abstract: A control device for a magnetic cylindrical lock having a cylindrical housing and a cylindrical plug disposed for rotational and axial movements in the housing, comprises a longitudinal boring in the plug, magnetic rotary members arranged for rotation across the longitudinal boring, and arresting means for blocking the rotation of the plug in one axial position of the latter and for permitting the rotary movement in another axial position.

Abstract: A cylinder lock has a lock body with a cylindrical throughbore and two longitudinally extending grooves in its internal surface. A lock cylinder is mounted in the throughbore for rotation therein between a locking position and an unlocking position and has a longitudinally extending key passage and is responsive to the insertion of a suitable magnetic key in the key passage to enable rotation thereby from a locking to an unlocking position. A plurality of magnetic bodies are mounted on both sides of the key passage for rotation about an axis perpendicular to the longitudinal axis of the cylinder to a unique angular position when the suitable key is inserted with corresponding recesses which are longitudinally aligned in two lines when the magnetic bodies are in their unique position.

Abstract: A security door system includes an actuator mechanism housed in a box-like, closed housing to minimize the possibility of tampering with the actuator mechanism such as would permit unlawful entry through the door. The actuator mechanism drives one or more, and illustratively two, bolts which extend horizontally across the door. One of the bolts enters a receiver in the jamb along the edge of the door opposite the hinged edge. The other bolt enters a receiver provided in the jamb along the hinged door edge. The security door system further includes a jamb and frame construction in which the jamb and surrounding frame cooperate to provide the bolt receivers. A metal reinforcing plate which is fixed to the frame by long wood screws, or the like, forms a wall of the receiver. This metal walled, deep receiver is less susceptible to damage by tampering, such as by springing the jamb or ramming against the door, than prior art security door systems.