Abstract: In a fuel assembly for a nuclear reactor a fuel element spacer formed of an array of laterally positioned cojoined tubular ferrules each providing a passage for one of the fuel elements, the elements being laterally supported in the ferrules between slender spring members and laterally oriented rigid stops.

Abstract: A device for quickly stopping a remote controlled automatic cannon having a breech block which can be moved by means of an endless control groove in an essentially rotationally symmetrical control roller, with each region of the control groove being associated with a respective function step within the firing cycle of the cannon. The device includes an element which rotates in dependence on the control roller and is provided with a stop abutment which is associated with a region of the control groove; and a control piston, which corresponds with the stop abutment, and which, during operation, can be moved axially, by propellant gases developed during firing of the cannon, so that one free end of the piston moves out of the circular path of movement of the stop abutment against a return force, and thus from a blocking position with respect to the stop abutment, into a release position with respect to the stop abutment.

Abstract: A piston head structure in which a piston head made of a ceramic is firmly secured to the top portion of a metallic piston body through the medium of a metallic ring fitted to the lower part of the piston head. In assembling, the ceramic piston head to which the metallic ring is fitted beforehand is secured to the top portion of the piston body by a shrink fit or, alternatively, the assembly of the ceramic piston head and the metallic ring is inserted to the metallic material of the piston body during casting of the latter, and the cast piston body is then subjected to necessary mechanical processing. In this structure, the separation of the piston head from the piston body is prevented due to the close fit of the ceramic piston head and the metallic ring to the metallic piston body. Such a fit prevents separation even when the piston body is expanded due to the heat generated during operation of the engine.

Abstract: A semiautomatic shotgun having a gas operating mechanism for unlocking a bolt and moving it from battery position. The operating mechanism includes an action bar and an inertia weight assembly which comprises a plurality of inertia elements. The inertia elements, the action bar and the bolt are arranged for movement relative to each other and impact at different times during the operating cycle. A return spring cooperates with the inertia weight assembly to maintain the various parts of the mechanism in fixed position relative to each other when the bolt is locked in battery.

Abstract: Seismic restraint means are provided for mounting an elongated, generally cylindrical nuclear radiation detector within a tubular thimble. The restraint means permits longitudinal movement of the restraint means and the radiation detector into and out of the thimble. The restraint means includes spring bias means and thimble constant means whereby the contact means engage the thimble with a constant predetermined force which minimizes seismic vibration action on the radiation detector.

Abstract: A lamp assembly for an automobile comprises a tilting member such as a lamp unit or reflector adapted to be moved by optical axis adjusting rods threadedly engaged with self-locking nuts relative to a support member such as a lamp unit casing or the like fixed to a vehicle body or the like so as to adjust an optical axis of the lamp unit or reflector. According to the invention, each self-locking nut is formed with two engaging grooves extending in directions perpendicular to each optical axis adjusting rod. One of the grooves has two opposite surfaces formed with round extensions extending toward each other. The other groove has a bottom having a convex along its generatrix.

Abstract: A pressure surge attenuation system for pipes having a fluted region opposite crushable metal foam. As adapted for nuclear reactor vessels and heads, crushable metal foam is disposed to attenuate pressure surges.

Abstract: The present invention discloses a blank firing attachment for gun tubes of utomatic or semi-automatic weapons when firing blank cartridges. The attachment includes a flash suppressor having milled axial slots threadably attached to the gun tube, a slidable cam pivotally mounted to a collar threadably attached to a shaft containing a restricted passage for gas flow from the gun tube, and a number of locking lugs pivotally connected to the collar. Axial movement of the shaft causes the lugs to engage the axial slots and the shaft to engage the gun tube end, thereby restricting gas flow from the gun and providing back pressure to permit automatic or semi-automatic firing of the weapon when using blank ammunition. Thus, the attachment is made compact and is fireable in all modes for various weapons, including M231 weapon.

Abstract: A firearm, particularly a sporting gun, having a rotatable bolt with a locking head and being equipped with a trigger mechanism accommodated in a trigger housing is disclosed. An angled reset member is engaged by the rotatable bolt through a pressure pin, in order to transform the rotary motion into a linear motion. For this purpose, the pressure pin is connected to the reset member, cooperates with a locking projection of the bolt. Upon turning the bolt, the reset member is caused to butt against a contact surface of the pivotally mounted first trigger which is connected to a pivotally mounted hair trigger. The hair trigger is thus pivotable to a safety position.

Abstract: This invention teaches an encapsulated fuel unit for a nuclear reactor, such as for an enriched uranium fuel plate of thin cross section of the order of 1/64 or 1/8 of an inch and otherwise of rectangular shape 1-2 inches wide and 2-4 inches long. The case is formed from (a) two similar channel-shaped half sections extended lengthwise of the elongated plate and having side edges butted and welded together to define an open ended tube-like structure and from (b) porous end caps welded across the open ends of the tube-like structure. The half sections are preferably of stainless steel between 0.002 and 0.01 of an inch thick, and are beam welded together over and within machined and hardened tool steel chill blocks. The porous end caps preferably are of T-316-L stainless steel having pores of approximately 3-10 microns size.

Abstract: An infrared decoy member is provided with a pyrotechnic chain for ejection and ignition incorporated in a unit. The ejection charge is mounted to slide in a cavity which allows the ejection of the unit as well as of adjacent infrared charges. A slide, which can be released when an acceleration threshold is crossed and on condition of ejection could ensure the transmission of fire to a transverse channel leading to useful charges. A second fire-transmitting chain which is independent, makes it possible to excite previously a similar decoy member located below.

Abstract: A storage structure for storing radioactive materials. It includes tubular storage members provided near the bottom thereof with a plurality of horizontal bolts the longitudinal axes of which intersect at a common point of said axes. A plurality of support plates for said tubular member is provided at the lower end thereof. Each support plate is adapted to support one of said plurality of bolts and each support plate includes an upstanding portion. Said upstanding portion of each of said plurality of support plates is provided with an open recess including an upper relatively wide slanting entrance adapted for insertion of one of said plurality of bolts and a lower bolt-bearing surface coaxial with one of said plurality of bolts. One support plate may have several upstanding portions of which each has a recess for the insertion and the support of a bolt projecting from a different tube for storing radioactive materials.

Abstract: There is disclosed in the present application, a decontamination system for reactor vessels. The system is operatable without entry by personnel into the contaminated vessel before the decontamination operation is carried out and comprises an assembly which is introduced into the vertical cylindrical vessel of the typical boiling water reactor through the open top. The assembly includes a circular track which is centered by guideways permanently installed in the reactor vessel and the track guides opposed pairs of nozzles through which water under very high pressure is directed at the wall for progressively cutting and sweeping a tenacious radioactive coating as the nozzles are driven around the track in close proximity to the vessel wall. The whole assembly is hoisted to a level above the top of the vessel by a crane, outboard slides on the assembly brought into engagement with the permanent guideways and the assembly progressively lowered in the vessel as the decontamination operation progresses.

Abstract: Heat retarding closure system for partitions having pressure relief openings formed therein especially in nuclear reactor buildings where main coolant nozzles of a reactor pressure vessel penetrate a biological shield, including lightweight construction closure elements having a side facing the reactor and anchors for holding the closure elements, the closure elements being pushable out of the anchors by an overpressure in a given pressure difference direction on the reactor side, and an outer sealing blowout skin, the closure elements being in the form of heat-retarding cassette inserts having a front surface with a peripheral shearing edge formed thereon resting against the blowout skin, and the blowout skin having a given thickness in the given pressure difference direction enabling the cassette insert to shear off the blowout skin and be pushed out of the anchors when a given pressure difference is at least reached.

Abstract: A gas cooled, high temperature nuclear reactor is provided with a base plate arranged under the reactor core and over the bottom of the prestressed concrete pressure vessel serving as the bottom shield. The bottom shield comprises at least two plates arranged coaxially with respect to each other, one above the other. Each plate comprises several partially interconnected parts with the lower plate being placed at an axial and vertical distance from the bottom liner of the prestressed concrete pressure vessel and also from the upper plate.

Abstract: An apparatus for removing a radioactive substance from a molten metal which comprises a cold trap for crystallizing an impurity out of the molten metal; a radioactive substance-adsorbing unit which communicates with the cold trap and in which a radioactive substance-adsorbing material is filled with a specific surface area of at least 10 cm.sup.2 /cm.sup.3 to eliminate a radioactive substance from the impurity; means for heating the molten metal conducted from the cold trap to the radioactive substance-adsorbing unit; and means for controlling the temperature of the heating means by measuring the temperature of the cold trap and radioactive substance-adsorbing unit.

Abstract: A nuclear reactor fuel assembly for a nuclear reactor comprises a housing with a wall and spacer means removably located within the housing, the spacer means comprising a plurality of spacer cells each adapted to receive an elongated fuel rod for the purpose of locating a bundle of such fuel rods in spaced-apart relationship within the housing. A portion of the housing which confronts the spacer means is provided at least at one location with a first locking means, and one of the spacer cells is provided with a second locking means movable between active and inactive positions. This second locking means is prevented from moving past the first locking means in the direction of elongation of the fuel rods when the second locking means is in its active position but is able to move past the first locking means when in its inactive position. The second locking means is moved from its inactive position to its active position by the insertion of a fuel rod into said one spacer cell.

Abstract: Fuel assemblies of a nuclear reactor are transferred during fueling or refueling or the like by a crane. The work-engaging fixture of the crane picks up an assembly, removes it from this slot, transfers it to the deposit site and deposits it in its slot at the deposit site. The control for the crane includes a strain gauge connected to the crane line which raises and lowers the load. The strain gauge senses the load on the crane. The signal from the strain gauge is compared with setpoints; a high-level setpoint, a low-level setpoint and a slack-line setpoint. If the strain gauge signal exceeds the high-level setpoint, the line drive is disabled. This event may occur during raising of a fuel assembly which encounters resistance. The high-level setpoint may be overridden under proper precautions. The line drive is also disabled if the strain gauge signal is less than the low-level setpoint.

Abstract: A hydraulic shock absorber of the dash pot kind for use with electrically conducting liquid such as sodium, has magnet means for electro magnetically braking a stream of liquid discharged from the cylinder. The shock absorber finds use in a liquid metal cooled nuclear reactor for arresting control rods.

Abstract: A drum magazine particularly intended for feeding shotgun shells to a firearm such as an autoloading assault shotgun. The drum magazine includes a cartridge-carrying rotor having a pair of sprockets, and powered by a torsion spring disposed on a central post within the drum. A last-round cartridge follower, removably carried by the rotor, can move either to a radially-extended position to feed the last round from the drum, or to a position of reduced effective radius to accommodate the first round in the fully-loaded drum. The drum magazine is adaptable to shells of different lengths.