Abstract: A sound absorbing panel for use in industrial sound control is disclosed and includes a sound absorbing material completely enclosed in a heat shrunk plastic material and supported by a frame extending about the outer edge of the enclosed sound absorbing material.

Abstract: A steel floor construction for freight hauling vehicles includes a plurality of elongated floor planking members arranged in side-by-side relation to provide a load bearing floor with a nailing groove between adjacent planking members. Each plank includes a downwardly open channel member having a relatively wide central web supported along its edges by integrally formed downwardly extending flanges, with the web being reinforced along its length by an upwardly directed generally U-shaped member welded to its bottom surface and having a pattern of anti-skid projections die-formed on and project upwardly from its top surface. The channels are progressively roll formed from a continuous length of strip steel by passing the strip through a series of forming roll pairs.

Abstract: A system for double glazing existing panes in windows or the like in which a pane of translucent or lightaltering material is cut to the shape of the exposed surface of an existing windowpane within its sash. The additional pane is secured to the existing pane through the use of magnetically intermateable spacer strips which are secured to the added and existing panes around their outer periphery by means of an adhesive. The intermateable spacer strips are of a thickness which allows for separation of the two panes by a sufficient distance to create an air space therebetween to enhance the insulating properties of the structure. A thin flexible strip of decorative material is secured to the surface of the attachable pane opposite the existing pane along its periphery so as to overlap the adhesive on the opposite face of the attached pane while extending outward to overlap the inside edges of the sash and thereby additionally seal and insulate the area around the outer periphery of the attached pane.

Abstract: A wiring distribution system for fill-on-slab or fill-on-grade floor constructions, including an uninterrupted main unit providing main passageways and at least one laterally extending feeder unit providing feeder passageways supported on a substructure (-slab or -grade). A housing having a removable cover encloses a full-width segment of the main unit and an end segment of the feeder unit. A covering layer of concrete (fill-) surrounds the housing. A partition divides the interior of the enclosure into two compartments, a first communicating with one feeder passageway and a second communicating with the other feeder passageways. The main unit presents at least one common lengthwise trough extending through and beyond the opposite sides of the enclosure. First and second capping means enclose those portions of the common lengthwise trough on opposite sides of the enclosure to provide substantially unobstructed additional main passageways communicating with the second compartment.

Abstract: An attachment for attaching a precast concrete wall panel to a building in a manner which permits vertical movement of that wall panel relative to building structural elements. In one embodiment, the attachment includes inserts embedded in the wall panel near the top and bottom edges of the upright wall panel, a tongue element connecting the top inserts to a building beam, or the like, and a clamp attached to the bottom inserts to connect those inserts to a building foundation. The inserts have slots defined therein in which portions of the tongue and clamp are located to permit the wall panel and building to move vertically with respect to each other.

Abstract: Window structure for a solar collector shield or the like having a frame defining a row of separate window openings. A self-contained window unit is installed in each opening. Each window unit comprises a pair of rectangular glass panes held in laterally spaced parallel relation by a peripheral window frame. A mounting frame is provided for mounting each window unit in its window opening. Each mounting frame has overlapping frame members. Adjacent side frame members of adjacent window units also overlap. The overlap is for the purpose of excluding moisture and preventing heat loss. A peripheral window seal is provided for the same purpose.

Abstract: A prefabricated weatherproof roofing panel for new construction applicable directly to the roof rafters, or for older house construction where the existing roof and sheathing both need replacement, is described. Such prefabricated panels are complete per se and when applied by a carpenter to the roof rafters provide a completed roof construction without the need of the usual skilled roofing workman. The panels include a substrate of plywood covered with a felt sheet material saturated with asphalt. A plurality of shingle strips are secured to each panel over the felt sheet. The plywood substrates are disposed on the roof in edge-to-edge abutting relationship and the shingles of the respective panels extend over the abutting edges into an interlocking and interweaving relationship. The shingle strips of each panel are incised at there bottom edges to form a plurality of tabs.

Abstract: The present invention relates to a system for the demountable attachment of architectural components and particularly the demountable attachment of wallboard panels to conventional wall and partition framing members, in such a way as to permit individual panels to be removed for access to the wall cavity. A preferred form of the invention utilizes a series of barbed clips, mechanically fastened to conventional framing members along each panel intersection joint. The clips are provided with a series of resilient barbs, protruding in angular opposing directions so as to penetrate and engage opposing marginal edges of abutting wallboard panels. The clip barbs spear wallboard panel edges in a pawl-like manner to permit the wallboard panels to be urged inward to the framing member surface, there retained by the natural outward obstruction of the hinged barbs.

Abstract: A mounting element is provided for connecting a cladding structure to a support wall with the use of a wire anchoring member having one end mortared in the cladding structure. The mounting element has a plate-like holding portion adapted to be driven into the support wall, and an eye-like receiving portion adapted to receive the other end of the wire anchoring member. The mounting element may be manufactured from a thin sheet whose one part forms the holding portion, and another part is bent so as to form a sleeve-shaped receiving portion located centrally and extending lengthwise of the holding portion. An end face of the receiving portion may be offset relative to an end edge of the holding portion by a distance which is substantially equal to the thickness of the wire anchoring element. A leading end section of the holding portion may be bevelled so as to form an insertion tip.

Abstract: A maintenance-free post or building structural member having longitudinal grooves therein for mating with complementary brackets, which brackets are also adapted to mate with other building structural members, and end-adapters for mounting such posts and for connecting one post to other such posts at predetermined angles. The post is hollow and has a constant wall thickness. Each groove has a curved portion and a flat portion. The brackets may be moved in the grooves adjustably, and may be locked to the post without causing any deformation of the post or bracket.

Abstract: A modular building construction system having (a) a series of rectangular U-shaped in vertical cross-section modules, each having only two bearing walls opposite each other and joined by a floor panel and open on top, and (b) a series of rectangular tube-shaped in vertical cross-section modules, each having only two bearing walls opposite each other and joined by both a floor panel and a ceiling panel. The tube-shaped modules are used only on the top story, and the U-shaped modules are used generally as lower units. The modules on each level are installed end to end so as to form a continuous living space in the longitudinal direction and side by side so as to form a separate series of living spaces and double walls separating the living spaces in the transverse direction.

Abstract: Apparatus for packaging shoelaces in which flattened shoelace convolutions are moved away from a winding means for being received in an elongate lace confining channel of a first lace receiving unit which is then moved in a substantially vertical path into substantially aligned proximal relation to an elongate lace confining channel of a second lace receiving unit. The proximal portions of the units have elongate openings therein, communicating with the respective channels of the units, and through which the flattened shoelace convolutions are transferred from the channel of the first unit into the channel of the second unit. As this occurs a wrapper, previously positioned to extend across the elongate opening in the second lace receiving unit, is wrapped partially around the flattened convolutions.

Abstract: This specification discloses a manually operated portion packaging apparatus including an operating handle initiating and actuating each step in a sequence of steps to complete packaging of a portion of a substance such as food. A hand operated handle advances a conveyor carrying containers, causes a film dispenser to dispense sufficient amount of heat sealable film, causes a heated platen to press on a container covered by the film, and actuates a food dispenser and container dispenser. Manually powering such a machine reduces the cost in comparison to electrical powering yet substantially increases efficiency in comparison to manual execution of each step in the portion packaging sequence.

Abstract: A process is provided for the opening of envelopes made of cellulosic paper in which there is applied to at least one envelope edge as the sole reactant with the cellulose therein a non-noxious organic acid having at least one pK value at room temperature between about 1.5 and about 5, followed by the application of heat and mild mechanical action to the envelope edge.

Abstract: An apparatus for gently transferring delicate produce from a supply conveyor into a dry storage bin. The discharge head of the apparatus has a reversible delivery board which directs and uniformly stacks the produce within the bin without bruising the produce. The transfer apparatus utilizes a series of opposed brushes on a parallel conveyor arrangement to gently support and transfer the produce to the bin. The discharge head and the bin move relative to each other in both the horizontal and vertical planes to provide uniform layers of produce and to adjust for the increasing layers in the bin.

Abstract: In a sugar cane harvester of the type having a conveyor to carry the cane stalks, butt ends first, from a base cutter which severs the cane near ground level to a chopping cutter which cuts the stalks into billets, the conveyor consists of a series of transverse upper feed rollers and a series of oppositely rotated lower feed rollers, the cane being fed between the upper and lower feed rollers. Between succeeding lower feed rollers there are provided transverse cleaning rollers, driven in opposite direction to the lower feed rollers, and with radiating members which are adapted to catch and tear away leafy matter from the cane being conveyed.

Abstract: A rotary lawnmower includes a dish-like body defining the chassis of the lawnmower. The dish-like body has an upwardly extending side wall and a substantially continuous bottom wall. A set of wheels are mounted on this dish-like body. A motor is mounted in the body so as to cause the free end of the motor drive shaft to penetrate the bottom wall. The free end of the motor drive shaft is adapted for carrying a cutting blade thereon. A cover interfaces with the dish-like body to conjointly define therewith a housing enclosing the motor.

Abstract: An apparatus for separating intermixed heavier and lighter materials of varied dimension and mass-to-area ratios, being particularly adapted to harvesting fallen nuts intermixed with leaves and other foreign matter. The separator element is used where the fruit and foreign matter are being borne in a common air stream by means of imposing the separator in said air stream whereby a perforated surface on said separator carries the debris in a direction opposite from the movement of the fruit towards a collection zone. The debris is carried away from the separator zone by the mechanical action of the moving surface in addition to the debris carrying propensity of the air stream.

Abstract: In a down-the-row type of tree shaking apparatus, a support frame is pivotally mounted to a carrier vehicle for rotation about an axis which is parallel to the longitudinal axis of the vehicle, and a suspension frame, from which a tree shaking and clamping assembly depends, is pivotally mounted to the support frame for rotation about an axis which is transverse to the longitudinal axis of the vehicle. The shaking and clamping assembly includes a housing and a pair of clamping arms which are pivotally mounted to the housing for rotation about parallel axes which are perpendicular to the transverse axis of rotation of the suspension frame. Each clamping arm is retractable from the position it assumes during shaking through an arc of approximately 90.degree., and each arm is operated by a separately controllable hydraulic cylinder.

Abstract: The disclosure is of a haymaking machine with rotary rake heads and a chassis connected by a beam to a hitch device for coupling to a tractor three-point power lift, characterized in that the said connection beam is on the one hand pivoted at its forward end to the hitch device about a substantially vertical pivot spindle and on the other hand is fixed rigidly at its rear end to the support chassis of the rotary rake heads in such manner as to retain the said support chassis during operation in a position in which it constantly forms an obtuse angle with the direction of travel of the machine.

Abstract: Apparatus and method for displaying information regarding the operating conditions of ring spinning machines in a textile mill wherein at least one traveling unit, supported for travel along a predetermined path for traversing one or more ring spinning machines, carries detectors for monitoring ends of strand material normally being formed by traversed machines and a data system responds to the detectors for determining the condition of the traversed machines from the condition of the monitored ends. In accordance with this invention, additional sensors are provided on each machine for signalling operating characteristics of the machines.

Abstract: The thread deflecting element is provided with an arcuate groove through which the thread passes as well as with compressed air ducts which deliver compressed air at the entrance of the groove on the side within the groove curvature and at a point downstream of the groove apex on the side outside the groove curvature. The air is delivered via ducts within the plate forming the deflecting element. The travelling thread is relieved of a degree of tension in the deflecting element so as to equalize the tension in the two lengths of the thread loop passing over the two heating paths of the heater.

Abstract: An electronic timepiece having a molded casing made of resin for incorporating in one body, timepiece components including a windshield, display means including an electro-optical display element or pointers, timepiece driving means, battery cell case and external switch means.

Abstract: A 13-element array of digital time display elements is selectively energizable to display relatively large hour digits of value 0 to 9, or relatively small minute digits of value 0 to 9 in a relatively upper or a relatively lower position. Three such arrays, together with two vertical line display elements, in ordered horizontal alignment, provide a compact, multi-functional display capable of performing balanced or quadribalanced digital time keeping. Four such arrays aligned horizontally provide another compact, multi-functional display capable of performing balanced, quadri-balanced or chronographic digital time keeping.

Abstract: Analog display calendar watch having a window or windows and an hour spindle changing device in which the movements of the hour hand and the disc or discs of the calendar are synchronized.The calendar disc is driven once every 24 hours by a rocker lever which supports a plate having a catch engaging the calendar disc, the plate being rotated by a 24-hour wheel and effecting a whole number, greater than one, of turns in 24 hours. The width of the catch is slightly less than the space between two teeth of the calendar disc, so that any forward or backward movement of the hour hand, controlled by the hour setting spindle, permits an immediate forward or backward movement of the calendar disc.

Abstract: Disclosed is a timer provided with a cord so that the same may be worn as a pendant. The timer comprises two mating half housings, one of which carries a cap having a notch and secured to the adjacent housing by a screw or other suitable means. Intermediate the cap and the adjacent housing half is a stirrup shaped along its length to conform generally to the contour of the housing and extending through the notch and into the cap where it has an eyelet on one end through which the screw holding the cap passes to secure the stirrup in place. The other outer end of the stirrup has a loop. The ends of the cord pass frictionally through the loop and along the length of the stirrup, through the notch in the cap and are positioned within the cap and gripped securely between the cap and the adjacent housing half.

Abstract: A connection structure for a watch casing and a watch band comprises internal modules incorporated in the watch casing and external modules secured to the watch band which are electrically and positively connected through a relay connector having electronic conductors at the position where the watch band is fixed to the casing.

Abstract: The invention relates to a wrist watch and thermometer arrangement. The thermometer is carried in a channel which surrounds the dial face of the watch, and the channel is formed by a platform, surrounding the dial face and disposed on one side of the thermometer, and a removable member, disposed on the other side of the thermometer. Hold down means, consisting of thin strips of a material having spring-like characteristic, extend over the thermometer from the removable means towards the platform. To remove the thermometer, it is merely necessary to lift the removable means off the platform. The removable means may be attached to the platform by a plurality of screws. The thermometer is carried in the channel by a plurality of y-shaped stands, at least the top portions of which are made of an insulating material.

Abstract: A temperature control system safely and efficiently protects critical aircraft surfaces from reaching fuel auto ignition temperature with cooling provided by a relatively small and light heat exchanger.

Abstract: A double annular combustor is provided with a main stage section disposed on the radially outer side such that its length is thereby minimized to reduce the resulting NOX emissions and its profile is thereby linearized so as to reduce the impingement of hot gases against the combustor wall. The pilot stage section is located radially inward so that its increased length tends to increase the residence time for idle and thereby reduce the hydrocarbon and carbon monoxide emissions.

Abstract: The performance of the diffuser action of burner shrouds is improved by establishing a substantially uniform velocity profile across the shroud passage by introducing a strong secondary flow in the form of vortices that lead to a better velocity profile and much improved diffuser action in the shroud passages.

Abstract: The invention relates to a power take-off arrangement, particularly a power take-off arrangement from an engine, comprising a pump including a fixed casing defining an annular liquid chamber, a rotor with a vaned annulus rotatable in said annular liquid chamber and intended to be rotated over a relatively wide speed range, a liquid inlet to said annular chamber, a liquid outlet from said annular chamber, a gate between said inlet and said outlet intended to allow passage of the rotor thereby while obstructing the flow of liquid along said annular chamber externally of the vanes of the rotor, and means for maintaining the liquid outlet from said pump at a substantially constant pressure at speeds above a predetermined speed within said speed range.

Abstract: To permit mechanical override of an electrical command system to control deflection of the swash plate or eccentricity of an axial or radial piston pump, for example upon failure of the electrical control system, a group of valves 5-8 are connected to an electrical control unit 23 and an additional control valve 4, 4' with a manual control lever 18', 30' is provided, the deflection of the swash plate 1 or eccenter ring 28 of the pump being sensed by a position transducer 22 moved by a linkage which includes the manual control lever. In normal operation, the manual control lever is maintained by spring pressure to deactivate the control valve but, under emergency conditions, the manual control lever will operate the first control valve 4, 4' to admit hydraulic control fluid to position the swash plate, or eccenter ring, respectively, the consequent movement of which is fed back through the linkage to the manual control lever.

Abstract: The control system has an adjustable flow-rate pump and a fixed flow-rate pump which is supplied with hydraulic fluid via a supply conduit. A first throttle is interposed in this conduit and produces first signals in form of pressure differentials in dependence upon variations in the rotational speed of an ungoverned combustion engine which powers the hydraulic drive, which signals trigger flow-rate adjustments of the main pump. A second throttle is also interposed in the supply conduit and produces second signals in form of pressure differentials in dependence upon variations in the load upon the hydraulic motor of the hydraulic drive, which signals trigger movements of the throttle flap of the internal combustion engine towards the open or closed position thereof.

Abstract: A fluid horsepower control system is adapted to operate a fluid load by output of a variable delivery pump having a control cylinder governed by a pressure compensated variable orifice connected in multiple with a load sense control valve for causing fluid flow to be inversely proportional to pump discharge pressure and maintaining constant drop across the orifice, without requiring mechanical feedback from the variable delivery pump to the load sense control valve.

Abstract: An arrangement for controlling the operation of a fluid-displacement machine, such as a hydraulic pump or motor, which is equipped with an adjuster that adjusts the machine toward higher and lower throughputs in dependence upon the pressure of a control fluid acting thereon, includes a control valve which communicates the adjuster either with a high-pressure zone or with a low-pressure zone of a control circuit in different ones of its terminal positions. In addition thereto, the arrangement includes a pressure-limiting valve interposed between the low-pressure and the high-pressure zones of the control circuit. Both the control and pressure limiting valves are acted upon by the control fluid, the pressure of which is controlled by a common regulating valve.

Abstract: A control system for stopping a hydraulic motor in a predetermined position comprises a valve connected in parallel across the motor, the valve having a closed position and an open position in which flow is via a throttle orifice. When the motor is being driven normally the valve is closed. When the main control regulator for the motor is moved to stop the motor, the valve is automatically opened to allow limited fluid flow through the motor during a slowing down phase. A detector senses when the motor is a predetermined distance from its desired stopping position, and moves the valve to its closed position. Overload valves are provided to prevent overpressures.

Abstract: A two speed valve and bi-directional motor system is provided having a pair of motors, means for delivering pressure fluid selectively to either side of said motors, a two speed valve means receiving fluid on one side of said motors to selectively direct the fluid to one or both motors to provide high or low speed operation thereof and flow sensing means automatically connecting the discharge from the motors to the one motor not receiving fluid when the two speed valve is shifted to divert all fluid to one motor so that fluid is recirculated through said motor.

Abstract: In an apparatus for producing ice a compressor which via a liquid separator is supplied with cooling medium from an evaporator, transfers compressed medium to a condenser, the condenser being connected to a liquid collector which in turn is connected to the evaporator. A first controllable valve is connected in the communication path between the liquid collector and the evaporator, and a second controllable valve is connected in the return path between the liquid separator and the evaporator.

Abstract: A conventional split system air conditioner is combined with a compression cycle or heat pump system for supplying heat to a domestic water heater. The units are combined in such a way that significant energy savings can be achieved by circulating air in series through the outdoor evaporator coil of the hot water heating system and then through the condensing coil of the heat pump, or vice-versa. This has the advantage of increasing the coefficient of performance for both systems. The direction of air flow will be selected on the basis of achieving the greatest improvement in energy savings and can be provided with automatic reversal of the air flow direction, depending on the ambient air quality and/or the operating state of either unit.

Abstract: Viable fluids such as blood components are rapidly frozen in plastic or the like pouches for transportation and/or storage by placing a flat pouch slack filled with fluid between two substantially planar parallel restraining surfaces such as metal plates of greater perimeter than the flattened slack filled pouch which are rigid enough to prevent sagging of the pouch when it is vertically disposed and flexible enough to accommodate expansion of the pouch flat sides during the freezing operation. The restraining surfaces are retained against separation by retaining means applied against at least a portion of the outer surfaces of each pouch restraining means and the entire assembly is immersed in a cryogenic medium to rapidly freeze the fluid.

Abstract: A mechanical refrigeration system and method of operating the same with a combined hermetic compressor and suction accumulator unit. The compressor includes an electric motor and gas pump driven thereby enclosed within a hermetically sealed first casing having a top wall disposed thereabove in the normal operational orientation of said motor and pump. The accumulator comprises a second casing superimposed on the first casing, of inverted cup shape with the lower edge thereof joined to the first casing such that said first casing top wall closes the lower end of said second casing. Refrigerant fluid from the system suction return line enters the second casing via inlet means oriented to induce a whirling flow of refrigerant fluid in the accumulator casing generally concentric with the upright axis thereof, and a gas liquid-separating standpipe means is disposed within said second casing having a gas outlet extending through said first casing top wall and communicating with an inlet to said gas pump.

Abstract: A mechanical refrigeration system and method of operating the same with a combined hermetic compressor and suction accumulator unit. The compressor includes an electric motor and gas pump driven thereby enclosed within a hermetically sealed first casing having a top wall disposed thereabove in the normal operational orientation of said motor and pump. The accumulator comprises a second casing superimposed on the first casing, of inverted cup shape with the lower edge thereof joined to the first casing such that said first casing top wall closes the lower end of said second casing. Refrigerant fluid from the system suction return line enters the second casing via inlet means oriented to induce a whirling flow of refrigerant fluid in the accumulator casing generally concentric with the upright axis thereof, and a gas liquid-separating standpipe means is disposed within said second casing having a gas outlet extending through said first casing top wall and communicating with an inlet to said gas pump.

Abstract: A flexible drive coupling for innerconnecting a pair of rotatable shafts includes a hub and an outer member. The outer member has formed in it a central opening and is disposed so as to circumscribe the hub and to be generally concentric with the central axis of the hub. Secured to and disposed between the hub and the outer member is a flexing section. The flexing section includes a plurality of helically wound, radially alternating layers of a resilient material and a substantially inextensible material. The layers of the flexing section, when viewed in section taken transversely through the layers and generally parallel to the central axis of the hub, have widths that diminish with increasing radial distance from the hub. The widths of successive resilient layers, however, diminish with increasing radial distance from the hub at a faster rate than the widths of successive and intervening inextensible layers.

Abstract: A shock isolation coupling located in a drive train between a transmission and the engine flywheel. The coupling includes a drive plate and a driven plate, the driven plate being centrally located within an opening provided within the drive plate. The driven plate is connected to a driven shaft which supplies input torque to the transmission. The driven plate includes a plurality of protuberances, each of which is located within a separate recess formed within the wall of the opening of the drive plate. In the space between the drive plate and the driven plate, there is located an elastomeric material. Openings are formed in the material to control deflection. Different deflection characteristics can be achieved on opposite sides of the protuberances. Breaks in between the elastomeric material are caused in selected areas to control shear stress in the movements between the drive plate and the driven plate.

Abstract: A process for knitting a single-faced pile fabric is disclosed, based on the raising and lowering of conventional needles and the movement of throated sinkers, each sinker having the throat extended and provided with a sloping shoulder in the lower edge thereof, a re-entrant bevel on the upper leading edge and a notch on the upper edge.

Abstract: An apparatus for adjusting the thread feed rate and hence the thread tension of a multiple-feed circular knitting machine includes transducer means in the form of a resiliently biased rocker mountable on the machine. The rocker can operate one of two microswitches whenever the tension of a thread engaging the transducer is greater than a predetermined value and can operate the other when it is less than the predetermined value. The microswitches control the energization of a servomotor operable to increase or decrease the speed of a rotary drive for driving the machine's thread feed device as necessary in order to bring the thread tension to the predetermined value.

Abstract: A leather press in which two wedges are synchronously driven to raise a lower platen in the press from an open condition to a position adjacent an upper platen of the press. The lower platen is movably mounted on a support. The support and the wedges are in slidable engagement with one another to effect a preliminary closing of the press. A pressurizable expandable member such as a flexible diaphragm may be mounted between the movable platen and the support so that the platens are secondarily urged together by the application of hydraulic pressure, to apply the required working pressure, to a leather workpiece disposed between the platens. The diaphragm is preferably provided by a wall portion of an inflatable sac.

Abstract: Automobile door lock assembly of push-button type including a rotatable element axially movable with a push-button and an annular element co-axial with the rotatable element. The rotatable element is formed with an axially extending slot having a shoulder defined by a wide and narrow portions of the slot. The annular element has a lug adapted to be placed in the slot of the rotatable element so that, when the lug is placed in the position engageable with the shoulder, the axial movement of the rotatable element is prohibited but, when the rotatable element is rotated to place the lug out of the path of the shoulder, the axial movement of the rotatable element is allowed to release the latch in the lock assembly. The annular element has manually actuatable lever so that it can be actuated into locking position without using a key.

Abstract: The following specification describes a plurality of combination lock cylinders, each of the axially movable tumbler pin type and each having a drive plate initially rotatable in a selected one of two directions by the tumbler operating pins of a respective operating key to control a bolt. A lock cylinder extraction key having tumbler pins universal to each lock cylinder rotates the drive plate in the direction opposite the selected direction to align a slot in the drive plate with a boss in the housing for enabling removal of a respective lock cylinder from its housing.Each lock cylinder has one pair of bayonet slots extending in the selected direction and engaged only by bayonet pins on the respective operating key for enabling rotation of the drive plate only in the selected direction and another pair of axially offset bayonet slots extending in the opposite direction and engaged only by bayonet pins on the lock cylinder extraction key to enable rotation of the drive plate only in the opposite direction.