Abstract: A latch for a combination vent and escape hatch for buses and mobile homes. The latch can be used to hold the hatch door in a closed position that is rain-tight. Alternately, with just a push on the hatch door, it can be opened to a vent position and held there by the latch. When the user pushes on a release mechanism, the hatch door can be opened completely to allow an emergency exit from the vehicle. In addition, a release handle located on the outside of the hatch allows rescue workers to gain easy access.

Abstract: A releasable mount for window grilles and the like. A wall-mounted portion is attached to a wall near the window and includes a fixed housing with a latch member having an opening therethrough and a trigger pin mounted for movement from a cocked, extended position to a release position. A grille-mounted portion is rigidly attached to the grille and includes a latch pin having a cavity with a catch assembly inserted into the fixed housing and partly through the opening in the latch member. The catch assembly expands to a catch position upon contact of the latch pin with the trigger pin. Then the catch assembly catches on the latch member and prevents the latch pin from being withdrawn from the fixed housing. The trigger pin remains biased in the cocked position, and keeps the catch assembly in its expanded position. However, when the trigger pin is moved to the release position, the catch assembly may retract and enable the latch pin to be withdrawn and separate from the fixed housing.

Abstract: Disclosed is an operator for a door mounted by frame means so as to be slidable along a track between open and closed positions. The door has a peripheral edge which is engaged to provide a positive locking of the door. The operator includes a shaft rotatably mounted alongside the door. A locking pawl is mounted to the shaft for rotation therewith so as to be movable between an unlocked position remote from a door edge and a locked position overlying the door edge so as to block the opening thereof. A lockout lever is also attached to the shaft for rotation therewith, and is movable between an idle position whereat the shaft is rotated to bring the locking pawl to its unlocked position and a lockout position whereat the shaft is rotated to bring the locking pawl to its locked position.

Abstract: The invention concerns a window specially designed for emergency use. The window comprises a fixed outer frame (1) and a sash (2) mounted for normal horizontal pivoting movement between open and closed positions about axis Y--Y. Two arms (3) extend in the respective side rebates between the frame (1) and sash (2), and opposed horizontal pivots (6) are secured to the sash (2) and the arms (3) for such normal pivoting movement of the sash (2). Each arm (3) is connected to the top (1a) of the frame (1) by a hinge (4) and each arm is acted on by a respective telescopic gas spring (5) confined within the rebate but acting on the associated arm (3) to urge it outwardly of the frame (1). For normal opening and closing movement of the sash (2) for which a casement fastener (7) is fitted, the arms (3) are retained secured to the frame (1) by a catch arrangement that is operable manually by a control handle (8) separate to the fastener (7).

Abstract: A window grille latch device comprising an arm with a hollow tube which has a pair of steel balls received in a pair of holes formed in the hollow tube, a latch means having a inner hollow tube and a outer hollow tube to receive the hollow tube, a convex ring recess formed in the inner hollow tube to receive the steel balls, a slide bar received in the inner hollow tube to contact with the steel balls, a cable with a cover connecting with the rear end of the slide bar and a control means connecting to the cable for releasing the latch means.

Abstract: A security window includes a movable window sash having an outer frame subdivided by strong metal crossbars into small spaces for window panes too small to allow entry through the window sash by an intruder breaking the glass. The window sash slides vertically or horizontally in metal channel-shaped fixed wall frame members that permit the sash from being pried loose. A spring-loaded locking bolt is contained in a cylinder mounted interiorly of the wall in wall studs next to the window. The locking bolt is connected to an elongated rigid metal control rod extending interiorly through the wall, preferably through intervening wall studs, to a lever arm and crank mechanism in a remote location within the wall sufficiently far from the window that the lever arm cannot be reached through a broken window pane by an outside intruder. A return spring holds the locking bolt in a positive locked position engaged within aligned detents in the fixed outer window frame member and in the window sash frame.

Abstract: The invention disclosed herein provides a panic exit device for doors having in their active side vertically operating bolts extending from the top and bottom of the door and a mechanism for retracting the bolts. Usually, the retracting mechanism may be activated by using a key in an exterior door lock or by depressing a panic bar on the interior of the door. The improved panic exit device of this invention provide a device for actuating the bolt retraction mechanism which is mounted inside a semi-hollow enclosure which is integral with the door. The mounting is accomplished with screws hidden from view by the glass pane securing mouldings. The panic exit device of the invention also provides an improved dogging mechanism to lock the actuator device in the actuated position, while simultaneously preventing excessive play in the panic bar.

Abstract: An apparatus and method for controlling emergency ventilation of a liverstock building comprising an environment sensor (12), air operated trip mechanism (14), and a source(10) of compressed air. The trip mechanism (14) is connected to open or close doors, windows or other sources of ventilation in the building in response to the presence or absence of the compressed air. Upon sensing a deviation from a prescribed ventilation norm, the environmental sensor (12) controls application of the compressed air to the trip mechanism (14) via solenoid valves (24, 30) to reverse the state of the building ventilation, i.e., to close the ventilation source if open, or to open the ventilation source if closed.

Abstract: An emergency gate release for a lattice type gate having a lock on the gate for locking the gate to a static structure. The gate release includes a lock release mechanism on one side of the gate for unlocking the gate and a rotatable release knob connected to the lock release mechanism for actuating the lock release mechanism to unlock the gate without a key. The release knob is located on one side of the gate at a location remote from the lock and inaccessible from the other side of the gate.

Abstract: A barrier gate arm useful in controlling exits such as in parking lots is provided comprising a stiffening member, preferably of wood, encased in an extruded sheath, or sleeve made from polycarbonate. The arm provides for easy operation and for a quick repair after the inevitable damage by offending vehicles.

Abstract: A security grille for disposition at a window, door or the like has at least a pair of vertically spaced tubular cross bars and a vertically extending tubular side member through which the grille may be fastened to a wall. Horizontal legs of a pair of angle members telescope into the ends of the cross bars while vertical legs of the angle members telescope into opposite ends of the side member. The construction enables horizontal expansion and contraction to accommodate to different installations, enables use of the side member with grilles having different cross bar spacings in the vertical direction and enables variation of the location of the attachment of the grille to the wall without displacement of the remainder of the grille. In the preferred form, the side member is fastened to the wall by latch mechanism having an enclosed cam which normally engages a pin on the side member but which can be actuated to release the pin and open the grille with a single movement of an actuator lever.

Abstract: A circular door operating method and apparatus comprising two pairs of arcked door leaves, two pairs of arcked fixed panels arranged so as to form an enclosure defining a cylindrical wind blocking compartment. Each door leaf is hinged at an end and releasably coupled at the other end to a hanger assembly traveling on a circular track by means of a pulley mechanism. When a door leaf is released from the hanger assembly to pivot about upper and lower hinge mechanisms for operation as a hinged door, not only the upper and lower hinge mechanisms firmly support the door leaf in place but also a control unit disables the sliding door operation, thus providing a quick and safe escape from the building in the event of an emergency.

Abstract: An emergency exit in vehicles, particularly aircraft or spacecraft. The vehicle wall defines an emergency exit opening. A door is sealingly placed against and lockable with the vehicle wall. The door can be moved outwardly through the opening for completely opening the emergency exit.

Abstract: A burglar bar assembly mountable over a window or door opening in a building may be quickly manually released from an interior portion of the building. The manual release mechanism is actuatable without a need for keys, or the like, so as to allow a building occupant to escape through the window or door opening in an emergency situation.

Abstract: A removable window bar for mounting inside a window structure, which window bar is characterized by a parallel top and bottom bar and crossbar, spaced by vertical bars. The bottom bar is removably seated in a pair of bar seats fastened in oppositely disposed relationship to the window facing. A pair of latch stays are also mounted in the window facing above and in spaced relationship with respect to the bar seats, respectively, and a rotatable latch is provided on each of the extending ends of the top bar, which latch is designed to removably engage the latch stay on each window facing and removably secure the removable window bar in position in the window. Rotational manipulation of each latch facilitates removal of the latch from the companion latch stay and lifting of the removably window bar from the bar seats, in order to remove the removable window bar from the window.

Abstract: An electromechanical device for activating a rotating post that moves the leaf of a swinging door on a vehicle, especially a mass-transit vehicle. An electric motor activates the column by means of an intermediate worm gear. The motor outtake shaft is coupled to the worm-gear intake shaft. A worm wheel is coupled to the worm-gear outtake shaft, which activates the rotating post. The electromechanical activating device contains an emergency mechanism for uncoupling the worm-gear outtake shaft from the worm wheel in relation to their rotation. The mechanism incorporates a coupling that can be disengaged between the outtake shaft and the worm wheel, which is mounted over it coaxially. The mechanism also involves several balls situated such that they can be forced into recesses in the outtake shaft while simultaneously engaging axial grooves in the inner surface of the worm wheel.

Abstract: A window assembly controls ventilation and prevents passage through the window opening. Provides hardened steel horizontal bars spaced apart vertically a distance that prevents passage. The bars are welded to hardened steel frame members. The steel assembly is anchored in the wall by resistant anchoring elements. The bars may be secured in place by other means. Glazed aluminum vents have top rails that enclose the bars and pivot upon them. Aluminum frame members enclose the steel frame members and support operator means that rotate the vents on the bars to open and close the vents. The angle of opening may be limited to prevent the vent extending beyond the wall at walkways.

Abstract: A latch actuating handle system for a door comprises a bar along and carried by the inside of the door; a bar along and carried by the outside of the door; pivot mounting means carried by the door adjacent a perimeter edge thereof and for mounting the bars for limited pivotal movement between positions toward and away from the door; a latch mechanism longitudinally disposed in the inside handle and terminating in a latch bolt at the end of the bar adjacent the door edge; and a stationary actuator post carried by the door at a location spaced from the pivot mounting means and operatively engagable with the latch mechanism for movement of the latch mechanism between latched and unlatched positions in response to movement of either of the bars.

Abstract: A door pivotable open in one direction is made unhingeable from an opposite side. The door is mounted in a door frame having stop molding rebates disposed on different sides of the door for the left and right sides of the frame, and no stop molding or rebate on the top. The door is hinged at the left or right side by means of a mating pivot pin and receptacle in the door and frame or vice versa. A mechanism is accessible at least on the outer face of the door when the door is closed, to disengage the hinge parts and release the door. The door can also include alternative hinges on opposite edges of the door, the door being openable when one set of hinges is disengaged.

Abstract: A revolving door (10) adapted to be mounted in a doorway to provide access and egress. The door (10) revolves about a vertical axis and has an upper cam housing (20) and a lower cam housing (22). Radial slots (24) extend through cam housings (20, 22). Pins (26) engage slots (24) and secure doorwings (12) to upper and lower cam housings (20, 22). A mechanism is mounted within at least one of cam housings (20, 22) for permitting doorwings (12) to be collapsed in panic situations or to accommodate large objects. At least one of the upper and lower cam housings has lateral bores (34) extending therethrough and intersecting the radial slots (24) at right angles. The mechanism for permitting the cam housings to be collapsed includes a cam mounted on each pin securing the doorwing to the cam housing and a spring-biased detent mechanism mounted within the lateral bore.

Abstract: A window guard latch with emergency release comprising a bracket having a channel for receiving a portion of the window guard, a lock for engaging the portion of the window guard received in the channel, the lock having a trigger for releasing the engagement with the window guard, and a solenoid linked to the trigger to operate it. A control box, mounted inside the building has an RF signal detector and means to activate the solenoid in response to the detector to release the window guard. Smoke detectors which trigger an RF transmitter and portable push button RF transmitters can transmit an RF signal to remotely activate the release mechanism.

Abstract: An emergency exit structure for a personnel housing chamber including an exit opening sized and positioned relative the floor of the chamber to permit personnel to exit from the chamber in a crawling position on the floor of the chamber in the event of an emergency, a door assembly, including a releasably locked door panel covering the exit opening when not in emergency use.

Abstract: A window guard assembly having a first stationary frame rigidly attached to a window opening having a second frame hingedly attached thereto and sized to closely fit within the first frame. A grate is rigidly attached to the second frame. To prevent unauthorized entry, a channel attached to the second frame has a pair of locking bars slidably mounted in the channel and movable into engagement with apertures in both frames to lock the second frame in its closed position. A lever handle and extension arm are pivotally attached to the locking bars to cause movement between their locking and release positions.

Abstract: A collapsible revolving door in which a plurality of leaves (32, 34, 36) are mounted to an upper cam housing (52) and a lower cam housing (56) for rotation about a central axis. Each of the leaves is mounted to a cam (80) through a pivot shaft (60) for rotation about a central axis of the cam (80) and the pivot axis (60). Each cam (80) has substantially opposed engaging sockets (84, 86) and substantially opposed collapsing sockets (88, 90). Dentent mechanisms (92) have semispherical cam followers (96) which are positioned in the engaging sockets (84, 86) when the leaves are radially oriented about the central axis. Under panic conditions, the door leaves (32, 34, 36) rotate about the pivot shafts (60) against the retaining force of the detent mechanism (92), whereby the detent mechanisms will register with the collapsing sockets (88, 90). Adjustment blocks (98) are adjustable mounted in the housing (52, 54) to simultaneously adjust the bias on two adjacent detent mechanism springs (94).

Abstract: In a hinged security window grating that cannot be opened from the outside but which is readily releasably from within by the lowering of a vertical locking bar that engages the closed grating. The release mechanism includes a tubular member attached to the building wall for slideably engaging the lower end of the locking bar. The tubular member and corresponding point on the locking bar have slots which are engaged by one end of a pivoted lever, the opposite end of which has a pedal which, when depressed, pivots the lever so that it withdraws from the slots to permit the locking bar to vertically drop to release its lock on the grating.

Abstract: A release mechanism for a vehicle escape sash employs a latch mechanism of novel construction, with parts configured as keeper, hinged latch member, and sash bar. The keeper has a keeper flange that projects upward from a web of the keeper, and has a generally cylindrical undercut recess at its juncture with the web. The recess defines a latch seat. The latch member has a sash plate mounted to the window sash rail and a latch plate hingedly connected to the sash plate. A depending flange on the latch plate has a cylindrical head at its free end that fits into the keeper recess and makes continuous rolling contact therewith when the keeper and latch member are latched together. The sash bar is mounted onto the latch plate and extends inwardly over the latch member, the keeper, and the sash subframe. The sash bar both serves as a cover and as a release handle.

Abstract: A window guard with concealed hinges and standoff members, one standoff member having therein a pin member configured for being engaged by a rotatable double cam cylinder on a shaft member extending through a bushing into the interior of the structure, with a door knob or door handle connected to the other side thereof for ready disengaging of the latch mechanism.

Abstract: A system to prevent unauthorized entry into a room through a door or a window opening. The system includes a grille hinged on one side of the opening and bar means attached at one end to the grille and extending through a port in a wall. Means are provided to hold the bar means against an inner wall to prevent opening the grille.

Abstract: A device for automatically opening and closing a hinged door includes a motor having a drive shaft, a speed reducer, an operating shaft adapted to be connected to the hinged door and operatively coupled through the speed reducer to the drive shaft, a chain sprocket fixed to the operating shaft, a chain trained in mesh around the chain sprocket, a first rod having an end coupled to an end of the chain, with a first fixed to an opposite end of the first rod, a second rod having an end coupled to an opposite end of the chain, with a second flange fixed to an opposite end of the second rod, a first tubular body in which the first rod is axially movably disposed, a first spring disposed around the first rod within the first tubular body for normally urging the first flange in a direction away from the chain sprocket, a second tubular body in which the second rod is axially movably disposed, and a second spring disposed around the second rod within the second tubular body for normally urging the second flange in a

Abstract: An emergency exit is provided through a revolving door, having leaves angularly spaced from each other and rotatable in an enclosure in an operating condition, by automatically aligning all of these leaves parallel to a line of exit traffic through the enclosure. The revolving door leaves may be so aligned by first biasing the leaves toward each other, but maintaining the leaves angularly spaced by releasable retention against the bias exerted by such biasing, and by thereafter releasing such retention in response to an emergency condition and aligning the leaves automatically by force of the bias.

Abstract: A sensor activated, automatic sliding door assembly for installation in building entrance openings for automatic opening and closing of sliding doors. The roller track, drive belt pulley, door carrier, and door guide allow adjustment to compensate for distortion of the system as a result of stress caused by use or expansion and contraction of the building. The rotatable safety hinges, one-way hinges, door stops and electrical interruptors provide integrated safety devices to the automatic door assembly. Linear sliding devices such as linear bearings provide improved movement of the sliding doors on a linear track.

Abstract: An emergency release handle is pivotally mounted within an interior wall of a railcar and connected to pull a cable under emergency conditions to actuate a mechanism, such as a mechanism to open a door. The handle is normally maintained inside the wall by a flexible guard plate and retaining screws passing through screw holes which are connected to the wall surface. Manual gripping means is connected to the handle to permit a person to grip it and pull to cause the flexible guard to flex and pass the retaining elements and permit the handle to pivot and pull the cable.

Abstract: A latching mechanism for basement windows adapted to allow the basement window to be moved from a closed position to an opened one for emergency escape.

Abstract: An entrance for buildings comprises first and second doors mounted in a common door frame, each door including a lock stile positioned adjacent a lock stile of the other door when the doors are closed. A panic device is mounted on at least one of the doors for emergency opening thereof and a retractable latch is extended between the stiles of the doors when closed for minimizing or eliminating the unauthorized forced separation of the stiles into a position wherein the panic device can be actuated with an implement inserted from outside the entrance to release and open the door. Mechanism is included for interconnecting the latch and the panic device for retraction of the latch when the panic device is actuated for opening the door, thus providing both a safe and a secure entrance system.

Abstract: An automatic gate arrangement has a hollow and tubular lower post part defining an upright post axis and fixed to one side of the path, an upper end wall transverse to the post axis, and lower fasteners releasably securing the upper end wall to the lower post part. A support fixed to the upper end wall extends upward along the post axis therefrom and pivotally supports a gate shaft at the post axis. A reversible drive motor fixed on and underneath the upper end wall in the lower post part has a rotary output extending through the upper end wall. A transmission between the rotary output and the shaft converts rotation of the output into oscillation about the post axis of the shaft. A C-shaped gate projects laterally from the post axis and is secured to the shaft by connecting means for joint rotation about the post axis unless the gate and shaft are relatively rotated about the post axis with a force exceeding a predetermined maximum force.

Abstract: To prevent passengers in an elevator from opening the hoistway door when the car is well above the floor, a rotatable arm is located below the car and engages the hall door to prevent it from being opened. This arm may be reached from the floor, by opening the hoistway doors slightly, and rotated to disengage it from the door, which may then be fully opened.

Abstract: A wall mountable safety hatch comprising a pair of telescopically engagable door frames that insert through a conventional studded wall forming an emergency exit. A pair of flush mounted doors insert into the wall mounted frame and are held in proper alignment by a seat belt type fastener. Upon releasing the conventional seat belt clasp, the door falls from the frame exposing the emergency escape hatchway.

Abstract: A home security and garage door operator system includes a gas sensor for detecting the level of toxic gas in the garage. When the gas level exceeds a predetermined threshold the garage door is automatically opened. Lock out circuitry is provided for preventing the door from being accidentally closed as long as the gas sensor detects an excessive level of toxic gas in the garage. A two button transmitter is used to sequentially close the garage door and set a security alarm subsystem. Warning devices are activated if the security alarm is attempted to be set without the garage door and windows in the home being closed. Once the security alarm has been set, the lock out circuitry also disables the garage door motor control circuitry until the security alarm is first deactivated. The transmitter generates a digital pulse train according to a preselected code, with the operation of the dual buttons changing the state of a particular control bit in the pulse train.

Abstract: An improved barrier assembly for selectively preventing and allowing travel along a path includes a frame assembly situated beside the path, at least one elongated barrier arm having a blocking position projecting laterally from the frame assembly across the path for preventing travel past the barrier arm along the path when the barrier arm is in the blocking position, and a connecting assembly connecting the barrier arm to the frame assembly for swinging movement with respect thereto about a substantially horizontal axis between the blocking position extending across the path and a non-blocking position wherein the barrier arm extends substantially vertically along the frame assembly to be situated with the latter beside the path to permit travel therealong. According to the invention the frame assembly comprises a channel enclosure to which a barrier arm is connected by the connecting means, the channel enclosure being constituted by a member having a substantially C-shaped cross-section.

Abstract: A panel structure for mounting on any of various enclosures susceptible to explosions or excessive internal pressures, is formed as a self-contained unit mountable in sealing relation to a pressure-relief opening of the enclosure. Disclosed is a one-piece back plate with an integral mounting flange isolating all other frame components from the area in which a sealing function takes place. A peripheral seal on the closure panel exerts pressure against the back plate in a normal position of the closure panel, in a direction parallel to the lines along which internal pressure is exerted against the closure panel, thus providing an efficient seal about the entire periphery of the relief opening, without the necessity of precisely dimensioning the sealing gasket and frame components at the locations where they are interfaced for sealing engagement. The gasket includes side-by-side primary and secondary sealing beads, one of which projects forwardly a distance less than the other.

Abstract: The following disclosure shows a window security system. The window security system comprises a grate or security bar assembly that is hinged to the outside of a window and includes louvres attached to the grate for protecting against the elements and in particular, sunlight. The grate is hinged to the window at one side, while on the other side, it is secured by means of a latch comprising a pointed latch pin which is engaged by a pair of jaws that are pivotally actuated by a toggle member. The toggle member can be actuated by a solenoid or by a hand operated cable or other assembly attached thereto. The solenoid can be either pushbutton operated or operated by means of a smoke detector. The entire assembly, including the grate and the louvres are opened at the time of the smoke detector detecting combustion to protect against entrapping occupants in the building.

Abstract: A window assembly including a storable fire escape ladder is described including a first frame mounted in the wall of the building and having a window support frame positioned therein with the window support frame being pivotally connected at its upper end to the first frame to enable the support frame to be pivotally moved from a closed position outwardly to an escape or open position. The first frame includes a storage compartment at its lower end in which the fire escape ladder is stored. A panel member extends downwardly from the window in the window support frame and normally closes or covers the open outer end of the storage compartment when the window support frame is in its closed position.

Abstract: A lid for a vehicle roof opening has linkage hinging it to the roof structure accommodating tilting the lid upwardly in either of two directions, or elevating it bodily, for use of the opening to ventilate the vehicle, including provision for manually actuatable means both internal and external of the vehicle for separating parts of the hinging linkage to permit swinging the lid fully open for use of the roof opening as an escape hatch. In a modification, the lid is hinged for tilting in only one direction to a ventilating position or swinging to the full open position in the same direction.

Abstract: A vent-type window structure, having one or more vent sashes each mounted by means of a pair of hinges respectively disposed at the opposite sides of the sash, wherein at least one of the sashes is positively secured to each of its associated hinges only by a single manually removable pin, to facilitate rapid removal of the sash or sashes for use of the window opening as an emergency egress opening. Each pin has a manually graspable ring at the inner side of the sash, and projects through the side of the sash and the associated hinge, being retained by a yieldable element abutting the hinge; when the pin is pulled manually in an axial direction toward the center of the sash, the latter element yields to enable extraction of the pin. The two pins respectively on the opposite sides of a sash are positioned so that they can be easily withdrawn together by pulling them toward each other.

Abstract: An emergency release and rotary actuator including a cylinder containing compressed gas or ignitable chemical material, a pressure tube and electrically fired detonation means for releasing the gas into such pressure tube or igniting the chemical material to release the gaseous products of combustion there under pressure into such pressure tube, a piston within such pressure tube, the shaft of which extends outside the pressure tube and carries a lug which engages diverging slots in closely surrounding tubes, all except one of which is rotatable, and a shaft, gear, pulley, or arm attached to one or more of the rotatable concentric tubes. An electrical impulse from a sensing or manual switch causes a detonating force releasing gas or igniting the chemical to drive the piston, the shaft lug of which moves through the diverging slots to rotate at least one rotatable concentric tube to operate a latch, tighten a strap or position a panel or air bag.

Abstract: A break away wall structure including a door panel aligned edge to edge with a wall panel. The wall panel is locked in place by spring-loaded plungers which can be actuated by a handle kept from normal use. In the event of panic, due to a fire or an explosion, the force of the explosion or the pressure of people against the wall panel will force the wall panel open causing the door panel to open with the wall panel.

Abstract: A lid for a vehicle roof opening including a linkage hinging it to the roof structure to accommodate tilting of the lid upwardly in either of two directions, or elevating it bodily, for use of the opening to ventilate the vehicle and including provision for separating the linkage from the roof supporting structure to permit swinging the lid to a fully open position relative to the roof opening to provide an escape hatch.

Abstract: An escapable guard system includes means for securance of a grill having at each side thereof to be attached to a window frame or the like a channel with legs outturned; for co-acting with channels of this type a self-protective fastening system is provided which on unlocking provides instant full access to the window opening; the fastening system includes for one side of such a grill an angled guard latch which fits within a channel where it is secured by carriage bolts passing through respective square holes in the channel and into square holes in base members of this invention which the square under-portion of each rounded head of the carriage bolt type machine screw fits, leaving exposed only the featureless semi-spherical portion of the bolt head; this guard latch co-acts with a frame latch which covers the nuts on the carriage bolts when attached to a window frame and which can be locked to the guard latch by a padlock; for the other side of such a grill similarly secured hinge hooks are provided which

Abstract: Pressure equalization between the upper and lower compartments of an aircraft is provided through normally covered openings along the edges of the floor of the upper compartment. The covers each are comprised of a double-flap arrangement in which one flap is constructed as two hinged panels with locking features in order to hold the other flap in a clinging position. The space between the flaps participates in the air-conditioning circulation. In the case of a pressure drop in the lower compartment, the pressure differential tends to fold the winged panels, thereby releasing the locks so that air pressure can be equalized through uncovering of the openings.

Abstract: An air lock has a chamber and a pair of doors in respective walls of the chamber. Operators associated with the doors include closers normally biasing the doors to closed positions and fluid powered openers associated with the closers capable of overriding the bias of the closers. A control system, operation of which may be initiated by initial opening displacement of one of the doors or (in one embodiment of the invention) by manually operable remote switch means, provides for opening of one of the doors and latching of the other to prevent simultaneous opening of both doors. The latch means for the doors may be overriden by direct displacement of the doors for safety purposes. The control system also triggers air handling apparatus associated with the chamber.