Abstract: Apparatus including two two-degree-of-freedom gyroscopes and at least two accelerometers mounted on a turntable on a vehicle. The turntable can be positioned about a vehicle vertical axis in one or the other of two positions 180 degrees apart for alignment. After alignment, the turntable is caged into its zero degree position, and the instruments thereafter operate in a strap-down mode with the yaw, roll and pitch angles of the vehicle computed by computer mechanisms which are sensitive to signals from the gyroscopes and accelerometers.

Abstract: Apparatus for measuring papillary muscle contractility when subjected to electrical stimulus while immersed in a test bathing liquid includes a test chamber for maintaining the liquid at a controlled temperature and having a membrane for diffusion of oxygen into the liquid, arms for mounting a muscle specimen in the liquid, electrodes for providing an electrical stimulus, and a system for measuring the contractile response of the muscle when subjected to electrical stimulus.

Abstract: A method and apparatus for determining the tension of mine roof bolts and/or mine roof stability which utilizes the natural vibration frequency of the seated roof bolt and/or roof structure to provide indication of bolt tension and/or roof stability.

Abstract: A fluid flow monitor of the sort which detects the rate of formation of Karman vortices caused by a blunt obstruction in a fluid stream. The invention mitigates problems associated with the formation of spurious electrical signals not related to the Karman vortices by providing an amplifier which amplifies frequencies selected by a comparator arrangement the comparator arrangement being controlled by the value of a further signal proportional to the number of detected Karman vortices.

Abstract: The invention relates to a force limiting assembly that includes a force transmitting reciprocating output member carried by an actuator member mounted at one end for rotation in a force limiting assembly housing. A power input member is secured to the actuating member in the housing. The assembly is provided with a release mechanism secured to the assembly housing and mechanically releasably secured to the actuating member to thereby permit the actuating member to move axially into the housing. The axial movement into the housing occurs only when an axial force present in the actuating member, which force is directed towards the housing, exceeds a preset value which results in the sudden release and movement of the actuating member and the power input member into locking cooperation with a portion of the assembly housing.

Abstract: A tractor transmission is synchronized between four different speeds in each of two different high and low ranges and a reverse range. A top shaft coupled to be driven by the tractor engine has four different gears which are concentrically and rotatably spaced along the length thereof in constant mesh with a different one of a second group of four gears formed on the outer surface of a counter shaft. The counter shaft is selectively coupled to the top shaft by either of two pairs of synchronizers concentrically mounted on the top shaft between different pairs of the first four gears. High and low ranges are respectively provided by a first splined collar capable of coupling the counter shaft directly to a differential drive shaft and a second splined collar capable of coupling the differential drive shaft to the fourth gear disposed about the top shaft via a low range driven gear.

Abstract: A shaft centering device for assisting in the coaxial alignment of a drive pinion in relation to a driven member with which the pinion is selectively engageable by intermeshing of respective gear teeth thereon is proposed which comprises a spring ring element having radial projections thereto supported in the driven member and which bears on the gear teeth of the pinion about the periphery of such pinion.

Abstract: A brake operating device for a bicycle has a bracket which carries a control lever pivoted thereto and is adjustable mounted to a fixed member fixed to a handle bar of the bicycle. Structures are provided to enable the bracket position to be changed with respect to the fixed member to adjust the distance between the grip of the control lever and the handle bar without changing the relative position of an outer sheath of a control cable supported at the bracket with respect to a control wire of a control cable supported at the control lever.

Abstract: There is provided a cable tension regulator having a pivotable hub which is rigid with an operating lever. Two quadrants are pivotably mounted on the hub and have fixed on their peripheries respective cables for connection to a control or controlled element. Resilient means urge the quadrants to pivot in the direction corresponding to tensioning of the cables. Means are provided for locking the quadrants on the hub when an additional traction is exerted on one of the cables by the control element and for releasing the quadrants when the tensions of the two cables change simultaneously. Each quadrant is pivotably mounted on the hub by means of a disengageable one-way coupling which prevents, when in operation, the quadrant from pivoting under the effect of the resilient means. There is provided means for disengaging the one-way coupling when the respective cable is taut.

Abstract: A torsional vibration damper of the type having an inertia ring coupled to a hub by an elastomer member. The inertia ring is formed of two axially spaced ring parts. Each ring part carries an annular groove. A radially extending disc locking element (in the form of a flat washer) carries an axially extending key, the ends of the key being deformed towards a radially extending position by pushing the two ring parts together, the deformed key ends thus holding the two ring parts in assembly. The disc locking element also is compressed and thus exerts an axial force urging the two ring parts apart. In an embodiment, the disc locking element carries a second axially extending key, radially spaced from the first key and is similarly deformed into a second annular groove. In still another embodiment, one inertia ring part carries an integral, axially extending locking key. This key is received by a complementary annular groove in the other ring part, the disc locking element being optionally omitted.

Abstract: A chain gear for a bicycle is formed from an approximately rectangular metallic band-shaped plate which has gear teeth formed along one edge and which is equal in length to the peripheral length of the chain gear. The band-shaped plate is wound into a ring-shape and end portions of the band-shaped plate are secured together to form the chain gear. The chain gear is secured to a chain gear adapter of a bicycle by a fixing means, the adapter rotating in accordance with a pedalling operation.

Abstract: In a transmission having input and output shafts drivingly connected by fluid pressure operated ratio establishing devices an improved centrifugally actuated valve is provided to disestablish the driving connection maximum angular velocity of the input shaft. The valve includes a sphere disposed in a stepped bore which sphere is spring biased to a closed position for normal operation and which shifts in response to centrifugal force to an open position in a fluid flow path thereby exhausting the drive establishing device and also being flushed of any contaminants.

Abstract: A gear shift control system for an automatic transmission comprises an air flow sensor for sensing the quantity of air taken into an internal combustion engine and supplying a corresponding electrical signal to a differentiator which provides a derivative of the sensed intake air quantity. A vehicle speed sensor senses the speed of rotation of the engine crankshaft to generate a corresponding signal. A gear shift decision circuit is receptive of signals from the air flow sensor and vehicle speed sensor to define a gear shift control line on a two-dimensional coordinate system as a function of the received input signals on respective coordinate axes. The derivative of the sensed air quantity is used to shift the gear shift control line to a higher speed side of the coordinate system to permit the transmission to effect downshift operation.

Abstract: Tweezer forceps in which the gripping arms and end section at which they are joined are formed of a single sheet of resilient sheet material, the arms and end section forming an integral spring-element disposed within the plane of the sheet material, such that the arms flex edgewise into and out of gripping engagement at their tips. Finger pieces are provided on the arms for engagement by the user's fingers when squeezing them together. Provision may also be made for aligning the arms against lateral displacement, and a jaw-locking device may be provided.

Abstract: There is disclosed a novel ratchet wrench assembly comprised of a barrel assembly visa-versa. a clutching mechanism positioned for rotational movement about a drive shaft of the ratchet wrench assembly including a drive stud and gear assembly. The clutching mechanism of the barrel assembly is interconnected to the drive shaft whereby rotation of the barrel assembly about the axis of the drive shaft in either direction causes the drive shaft to rotate in response thereto and thereby rotate the drive stud through the drive stud and gear assembly in a responsive rotational direction. In a preferred embodiment of the present invention, the clutching mechanism is designed such that the rotational movement of the barrel assembly and the drive stud are coincident, i.e. counter-clockwise rotational movement of the barrel assembly results in a counter-clockwise rotational movement of the drive stud, and thus loosening of a bolt or nut mounted on a right hand threaded stud, and vice-versa.

Abstract: A split socket ratchet wrench is provided. The wrench has an elongate handle terminating at jaws at the head end of the wrench. The jaws receive a rotatable split socket and ratchet wheel rotatable therein. A manually actuable pawl has extending projections engageable with the ratchet teeth. A separate cable spool at the handle end of the wrench is fitted with a torsion spring. A cable or filament extends between the cable spool and the ratchet wheel. As the socket is rotated, it carries with it the cable which is spooled around a hub of the socket. When the wrench is disengaged from the nut, the pawl can be released and the cable spool will rewind returning the socket to the normal "open" position at which point a registry stop on the socket prevents the socket from rewinding past the open position. A separate locking device senses when the cable spool is completely payed out and prevents the mechanic from further turning the socket.

Abstract: The tool of the present invention comprises a pair of locking pliers with jaws specifically designed to include a threaded cavity complementing a threaded hanger rod, so that the jaws may be quickly closed and locked to grip the rod and support an object to be hund thereon until a permanent threaded support nut can be threaded on the rod and run up to the support position. In one version of the invention, the threaded cavity is formed in a pair of adapter inserts, so that different pairs of inserts may be interchangeably received and held in the plier jaws, which are thus adapted to grip threaded hanger rods of different size and different threads.

Abstract: An apparatus for assembling the components of a trophy includes a socket for engaging a nut employed to connect the components, a bidirectional motor coupled to the socket, a clutch mechanism coupling the bidirectional motor to the socket, a spring retained between the motor and the socket to allow axial movement of the socket relative to the motor, and a bracket for adjustably mounting the motor, clutch mechanism, and spring beneath a work surface for supporting the components of the trophy. The socket is biased upward by the spring so that it projects above the working surface. The motor is operable in a first direction to tighten the nut and in a second direction to loosen the nut. The clutch mechanism provides a torque-limited connection between the motor and the socket in the first direction to prevent excessive tightening of the nut and a positive connection in the second direction to loosen the nut.

Abstract: A cutting tool, preferably in the form of a cutting insert of hard material, having a narrow land area or ledge along the cutting edge, forming a shallow recessed groove promoting the formation of a false cutting tip build-up during use of the cutting tool, the cutting tip build-up resulting from the transfer of material from the chip to the ledge surface. The cutting tool of the invention enhances and favors the formation of a cutting tip build-up by providing the shallow recessed groove with a width which is a function of the cut taken by the cutting tool in a workpiece such that the chip removed from the workpiece during a cutting operation bridges the recessed groove.

Abstract: A sealing ring is disclosed which is formed of an elastomeric material wherein the cross section thereof has a plurality of substantially flat surfaces, and wherein the inner and outer diameter surfaces, which are the sealing surfaces thereof, are molded surfaces. The remaining surfaces are machined or cut surfaces. The preferred number of surfaces or faces in cross section is 8, and this has been found to give the best results, although other numbers of surfaces may also be used. Since the ring itself is not a molded ring, but has only the inner and outer surfaces thereof which are molded, there is also disclosed a novel method of making such a ring, as well as a novel apparatus for use in a carrying out the method of making the ring, wherein a molded elastomeric sleeve is provided and wherein inclined surfaces are cut therein in such a way that when the ring is severed from the sleeve it will have the desired number of flat surfaces.

Abstract: Method for removing camber from strip preparatory to forming helical pipe is taught utilizing the steps of feeding the strip longitudinally along a directional line of feed, sensing lateral deviations of the strip relative to the directional line of feed, laterally moving and realigning the strip in response to lateral deviations, then severing both side edges of the strip on lines parallel with the directional line of feed.

Abstract: A cutting apparatus for cutting blocks of e.g. cheese into portions for delivery to an automatic packaging machine comprises a platen 15 mounted on a hydraulic ram 16 which can be advanced in steps to force a block of cheese 14 located on the platen upward through fixed cutting wires mounted in a frame 17. After each advance of the platen a cutter 19 severs a layer of portions which are transferred to the packaging machine. Signals from a digital encoder 39 are supplied to a micro-processor which controls the steps in which the platen is advanced so that the block 14 is completely cut into portions none of which in thinner than a predetermined thickness whereby remnant waste is eliminated.

Abstract: There is disclosed an envelope processing machine in the form of an improved envelope cutter apparatus adapted to sever one edge of envelopes in one by one relationship. The apparatus includes a supply hopper for retaining the envelopes to be processed, cutting means for severing one edge of the envelopes, means for removing envelopes in one by one relationship from the supply hopper and for transmitting the removed envelopes to the cutting means, and means for orienting the envelopes in respect to the cutting means. The orienting means includes a plurality of angularly disposed feed belts operable upon the envelope and an abutment member against which an envelope is engaged in its movement to the cutting means.

Abstract: In a band saw (10) particulaly adapted for cutting meat, blade scrapers (25, 26) remove debris from the band saw blade (18) and throw it laterally and forward of the blade (18) into an enclosure (40), which can be removed without the use of tools for cleaning and for disposing of the collected debris. The location of the blade scrapers (25, 26) is slaved to the location of the saw blade (18) to automatically maintain the proper relationship for most efficient debris removal without adjustment.

Abstract: A cutting machine having a circular cutting tool, such as a saw blade for cutting a workpiece in two, has the blade mounted on an arm to swing from an inactive or raised position above the workpiece down into engagement with the latter. A guard protects the operator of the machine from the blade and includes a cylindrical cover journaled to turn relative to the blade and enclosing both sides and the edge of the blade. A notch is formed in the cover and faces away from the operator when the blade is in the raised position and a link turns the cover automatically as the blade is lowered so that the notch faces downwardly and exposes the blade to the workpiece. When the blade is in the raised position, the notched portion of the cover projects into a shell so that the blade is completely enclosed at that time.

Abstract: A press drive with a central cam shaft actively connected through a connecting rod with a slide guided in a linear guide. Side bars are symmetrically articulated with respect to each other on the slide. Mass balancing weights are driven in opposed directions corresponding to reciprocating masses of the press, with the weights being connected with the slide by other linkages. Pairs of toggle joint linkages are disposed symetrically with respect to the cam shaft. The pairs of toggle joint linkages include a first almost horizontally disposed toggle joint linkage that is articulated on the respective side bars and presents a bearing point on the press frame. A second almost vertically disposed toggle joint linkage that is connected with the first toggle joint linkage and is articulated so as to be guided by the press frame on the mass balancing weight.

Abstract: An electronic organ, particularly of the institutional type employing classical voicing, having Swell and Great manuals as well as a full pedalboard wherein the manuals and pedalboard are multiplexed simultaneously to produce a plurality of synchronized serial data streams. Intermanual coupling is accomplished by connecting the data stream from one manual to the footage generation circuit of another manual, and footages are generated for each manual by utilizing tapped shift registers introducing controlled amounts of delay of the keyboard data before demultiplexing thereof. There is a bank of multiplexers for each voice, such as flutes, principals, complex and percussion, which receive the serial data streams from one or more of the footage generators. The demultiplexer-keyers are supplied with tones and function to demultiplex the serial data streams and provide tones selected in accordance with the keydown pulses in the serial data streams to the voicing circuitry.

Abstract: A multimode digital display assembly is configured to provide a real time alphanumeric display of notes and chords being played on stringed musical instruments, such as a guitar, as a learning or teaching aid. The display assembly is particularly well adapted to be retrofitted to a minimally modified guitar, and the display generating circuitry is specially selected for a low cost/low complexity implementation. Basic operating modes provide both a track, and latch display type, and an alternate operating mode uses sound produced by the instrument to initiate and update displays of the notes and chords being played.

Abstract: A carrier including one or more guide tracks, an endless positioning chain associated with each guide track for supporting a payload item, and one or more drive motors for moving the chains in unison with respect to the guide tracks to move a payload item toward an ejection station. A fairing may be mounted in association with the guide tracks. The guide tracks encircle the aircraft fuselage and are maintained under sufficient tension to apply a radial compressive force to the fuselage for securing them thereto. The guide tracks are laterally rigid but are flexible radially to conform to a range of fuselage contours when subjected to a tensile force. The guide tracks thus may be secured to different aircraft in order to temporarily transform the aircraft into a military payload carrier, with minimal modification. Following military employment, the aircraft may be refurbished for non-military usage by removal of the carrier.

Abstract: Portable anti-tank weapon including a projectile launch tube for firing a projectile at a target. A firing device having at least one firing tube for an illuminating projectile or flare is mounted on the launch tube, with the firing tube being at an angle of elevation relative to the launch tube. A combatant can fire the illuminating projectile or projectiles so as to illuminate to the approach to and the target area, thereby enabling him to sight and fire the anti-tank projectile.

Abstract: A method and apparatus for precisely aligning a top-mounted individually stabilized weapon on an armored vehicle by means of a fire control system including an optical observation and aiming system controlled by the vehicle gunner after a target, which has been optically sighted by the vehicle commander by means of a stabilized panoramic optical device, has been taken over by the vehicle gunner in his own individually stabilized optical device. After sighting a target the vehicle commander initiates a control signal which causes the actual values of position of his panoramic optical device to be transmitted to the stabilization control of the gunner's optical device as rated values resulting in the two optical devices being aligned.

Abstract: At an armored vehicle containing a firing weapon, such as for instance a cannon, there is required an automatic loading apparatus, by means of which the rounds of ammunition or projectiles can be automatically infed to the firing weapon from an ammunition magazine arranged behind an armored turret of the armored vehicle. The loading apparatus removes the projectiles from two different containers. This loading apparatus comprises two withdrawal or removal devices, two pivot devices, a rotatable table containing two cartridge receiving locations or stations as well as an ammunition infeed device. This ammunition device comprises a lifting or hoisting device, a loading cradle or shell and a rammer.

Abstract: In a hydraulic apparatus, operating oil delivered from a fixed delivery hydraulic pump is divided into two parts, one end of which is discharged into an oil tank by passing through a serial circuit of a normally open valve and an orifice and the other end of which is supplied to a piston-cylinder mechanism by passing through a parallel circuit of a normally closed valve and a check valve. When the normally closed valve is closed and the normally open valve is gradually closed, the piston is raised while gradually increasing in velocity. On the other hand, when the normally open valve is totally opened to stop the piston and the normally closed valve is gradually opened, the piston is lowered while gradually increasing in velocity. When the valves are operated to cause the piston to move vertically, the impact applied thereto at the time when the valve opening is large is largely mitigated by using the orifice.

Abstract: A bidirectional, multiple speed hydraulic actuator, including a differential piston (10, 24, 26). First and second ports (28, 30) are respectively in fluid communication with opposite sides of the piston and there is provided a pressure fluid supply line (40) along with a pressure fluid drain line (44). A control valve (14) is disposed between the ports and the lines and is movable step-wise through five positions providing for nulling of piston movement, and slow and rapid piston movement in either of two directions. A shifting device (60) is provided for the valve.

Abstract: A torque control for a fluid operated motor includes a first gear to be driven through operation of the motor and a second gear in driving engagement with said motor and maintained in a generally stationary position during normal operation thereof. The torque control further includes a drive mechanism connected to the first gear and to a load to be rotationally driven through operation of the motor. A valve is provided in the fluid supply to the motor to open and close the supply of fluid thereto. Disconnect means is operatively connected to the second gear and the valve to maintain said valve in an open position to permit supply of fluid to said motor when the second gear is stationary. The second gear rotates when the torque required from the motor to rotate the load exceeds a predetermined magnitude to move the disconnect means relative to the valve to close the valve to terminate the supply of fluid to the motor.

Abstract: Pressure control valves for mechanically controlled power brake units include a control casing with an approximately cylindrical guide member. The control casing houses a valve piston to which a piston rod extending through the guide member and projecting therefrom is secured. Prior to the mounting of the power brake unit, the piston rod may be subjected to lateral knocks which has to be absorbed by the control casing. Under increased knock impact, the result is frequently a damaged control casing. In accordance with the present invention this is overcome by arranging the piston rod shank which is adjacent to the end of the piston rod carried in the valve piston, at least partially within a bore of the valve piston and to dimension the radial distance between the bore and the piston rod shank such that the valve piston serves as a stop to limit the crosswise or radial movement of the piston rod.

Abstract: A hydraulic motor has a stationary housing, a hollow rotor having a plurality of hollow radially extending pistons each provided with two concentric annular walls forming inner and outer chambers communicating with separate fluid-conveying passages, a plurality of cylinders displaceable over the pistons and each having a projection received in the inner chamber of the respective piston, and a central control member having a plurality of fluid-conveying passages cooperating with the fluid-conveying passages of the pistons and displaceable in the axial direction between a plurality of operating positions.

Abstract: Apparatus for providing source capture of fumes produced at a work station including a molded aerodynamically designed fume capture hood positionable above the work station, a mounting mechanism for providing vertical movement of the hood such that the orientation of the hood opening remains constant, a fume collection system for removing material contained in air captured by the hood, and a flexible conduit connecting the collection system to the hood. The contours associated with the forward parts of the upper and side wall portions of the hood minimize entrance loss and turbulence to provide a coefficient of entry of at least about 0.93, while the contour associated with the forward part of the upper wall portion permits a higher velocity near the top of the hood for insuring suction of fumes, vapors or smoke near an operator's breathing zone.

Abstract: Louver structures having horizontally disposed overlapped members, whereby in one disposition, the louver structure sheds precipitation at one of its sides, and in reversed inverted disposition, the louver structure sheds precipitation at the other of its sides, in said one disposition the louver elements projecting from a wall in which the louver structure is installed, and in said reversed inverted disposition the louver elements being recessed into the wall in which the louver structure is installed.

Abstract: A method for cold peeling citrus fruit is disclosed wherein the fruit is first cored and sliced into a plurality of segments and the pulp is thereafter severed from the peel by forcing the segment through a knife. An apparatus is disclosed where the fruit segment is secured and compressed on a concave rotary carrier which is then rotated through a concave severing knife which severs the peel and albedo from the pulp.

Abstract: A continuous motion ribbon imprinter moves with and marks a moving web on a packaging machine and has an easily set control adjusting step-by-step advance of the ribbon across the type block to accommodate wide variations in the size of the printed indicia so as to always present just enough length of fresh ribbon to cover the type for the next imprint. A frame mounting the type block and ribbon reels swings in either a clockwise or counterclockwise orbital path having a dwell stroke on the moving web, and a lift stroke spacing the ribbon from the web. The ribbon remains stationary on the type block during the dwell stroke and is advanced across the type block on the lift stroke. A single input shaft drives the frame through its orbital path and also drives the mechanism for unwinding the fresh ribbon from one reel and winding the spent ribbon on a second reel.

Abstract: An ink fountain construction for a printing press having a trough extending adjacent and parallel to the fountain roller to define a control space occupied by a flow control strip. The control strip is made up of a series of separate and independent flow control segments in the form of identical blocks of rectangular shape arranged snugly side-by-side for zonal control of the ink film fed to the roller. Each segment is rigidly secured to the frame at its lower end. Each segment has a relatively thin central section and is sprung forwardly to bias the presented upper edge of the segment against the fountain roller. A set of pull rods connected to the upper ends of the segments have adjusting means at the rear end to draw the connected segment rearwardly to define a gap with the fountain roller to establish the rate of ink feed in the respective zonal position.

Abstract: A projectile having a light-settable photodetector pickup assembly, in the form of a plurality of photovoltaic cell units, circumferentially mounted on the annular surface of the projectile, and also having an angular-position-indicating index reflector on the surface thereof. Each discrete photovoltaic cell unit is electrically connected with an electrical signal storage unit which is activated as a function of light acting on the respective photovoltaic cell unit associated therewith. A further photovoltaic cell unit is preferably provided as a source of energy for storage unit and/or logic or other circuit of operation.

Abstract: A dual mode incendiary bomblet which combines the effects of a jetting indiary and a slow burning incendiary. A gas producing ejection means within the housing of the bomblet ejects the incendiary package (burning portion) of the bomblet and assures that it will burn adjacent to a target.

Abstract: This invention relates to a combustible sabot and process for its preparan for a spinning tubular projectile. This combustible sabot is prepared in such a way and of such materials that it combusts spontaneously while exiting the gun barrel. The sabot is fabricated from an anhydride cured epoxy binder, boron, molybdenum trioxide, ammonium perchlorate and a metallic fuel selected from either aluminum or magnesium in the presence of a catalyst.

Abstract: A vestibule connection for the adjoining ends of two cars of a rapid-transit vehicle includes an apron which is maintained centered in the space between turntables at the adjoining ends, by being mounted on two transverse parallel shafts via telescopable units that are pivoted to these shafts and alternate ones of which, as considered in direction lengthwise of the shafts, exert a biasing action on the apron in mutually opposite directions along the centerline of the two cars.

Abstract: An overhead suspension load transporting trolley which is suspended from a track, such as the flange of an I beam, which has a drive wheel suspended below a carriage, which wheel is biased against the I beam by a counterweight on the opposite end of a lever from the drive wheel.

Abstract: A side bearing assembly for railway rolling stock having an elastomeric body, containing granular solid substance, disposed between the body bolster and the truck bolster or side frame. The assembly is an inexpensive yet durable means for accomplishing increased support of static and dynamic loads without inhibiting the body bolster movement in a horizontal plane relative to its trucks.

Abstract: A flexible diaphragm can be moved to line opposite surfaces of a tank vehicle so that incompatible fluids alternately can be transported in the vehicle without the need for cleaning it. The diaphragm is prevented from entering a manway on the vehicle, and an outage gauge is confined entirely within the manway to prevent damage to the diaphragm.

Abstract: An auto railway car having a plurality of decks is provided with a pair of folding door structures for closing the loading end of the car. The doors are hinged on spherical bearing structures and include locking mechanisms for locking the doors in open or closed positions.