Abstract: An economizer control system includes a compressor including a compression area, a piston chamber, and an economizer inlet configured to receive economizer vapor into the compression area via a flow path that extends between the economizer inlet and the compression area. At least a portion of the flow path traverses the piston chamber. The economizer control system also includes a piston disposed within the piston chamber and configured to contact the economizer vapor. The piston is moveable between an open position that opens the flow path and a closed position that closes the flow path. Additionally, the economizer control system includes a biasing system configured to apply force to the piston to bias the piston toward the closed position.

Abstract: A heat exchange device may include a first pipe including a first inlet, a first outlet, and a first sidewall extending therebetween; a second pipe including a second inlet, a second outlet, and a second sidewall extending therebetween; and a plurality of dimples extending between the first sidewall and the second sidewall. The second sidewall may surround and extend about the first sidewall, the first sidewall may define a first fluid passage configured to permit flow of a first fluid, and the second sidewall and the first sidewall may define a second fluid passage configured to permit flow of a second fluid.

Abstract: A heat exchanger includes: a plurality of flat tubes arranged in a height direction of the heat exchanger; a connection portion in which a plurality of connection spaces are provided as spaces with which ends of the plurality of flat tubes are connected; and a refrigerant distributor connected to each of the plurality of connection spaces. The flat tubes each have a first side end portion located on a windward side, a second side end portion located on a leeward side, and a plurality of refrigerant passages arranged between the first and second side end portions. Each flat tube is inclined such that in the height direction, the position of the first side end portion is lower than the position of the second side end portion.

Abstract: A distributor distributes fluid to plural fluid outlets, the fluid flowing from a fluid inlet. The distributor includes plural branching flow paths having an upstream branching flow path, and downstream branching flow paths located closer to the fluid outlets than is the upstream branching flow path, and an intermediate flow path provided between the upstream branching flow path and one or more of the downstream branching flow paths, the intermediate flow path connecting the upstream branching flow path and the at least one of the downstream branching flow paths. The intermediate flow path has one end connected to the upstream branching flow path at a position facing one of the ends of the upstream branching flow path and the other end connected to one or more of the downstream branching flow paths at a center of the downstream branching flow path, and causes the fluid flowing from the one end to change a flow direction of the fluid and then flow out of the other end.

Abstract: In one instance, an isolator for a heating, ventilating, and cooling (HVAC) system is provided that is a formed plastic member that is disposed between dissimilar metals of the bottom of the condenser and a base pan that supports the condenser or between two dissimilar metals of another HVAC heat exchanger. The isolator separates the two dissimilar metals involved from each of those components and also provides gaps or apertures to drain any water that otherwise might become standing water that potentially causes oxidation or increased oxidation. Other aspects are disclosed.

Abstract: A heat pump system and a control method therefor. The heat pump system includes a compressor; an indoor heal exchanger; an outdoor heat exchanger, including a first heat exchange portion and a second heat exchange portion, wherein a flow path switching device is provided between the first heat exchange portion and the second heat exchange portion to disconnect or communicate the first heat exchange portion and the second heat exchange portion; a first four-way valve; and a second four-way valve, configured to enable a high-temperature refrigerant to be input into the first heat exchange portion in a heating mode, so as to enable the heat pump system to operate in a heating and deicing mode.

Abstract: A defrost method for a heat pump system includes running the heat pump system in a heating mode to provide heat to an enclosed space and determining if an outdoor temperature is less than an outdoor threshold temperature. Responsive to a determination that the outdoor temperature is below the outdoor threshold temperature, determining if a calibration state has been previously run. Responsive to a determination that the calibration state has not been previously run, running the heat pump system in the calibration state. Responsive to a determination that the calibration state has been previously run, determining if a temperature difference between a temperature of an evaporator coil of the heat pump system and the outdoor temperature exceeds a temperature threshold value. Responsive to a determination that the temperature difference between the evaporator coil and the outdoor temperature is greater than the temperature threshold value, running the heat pump system in a defrost state.

Abstract: Thermal management systems are described. These systems include a refrigerant receiver configured to store a refrigerant fluid, an evaporator, a closed-circuit refrigeration system having a closed fluid circuit path, with the refrigerant receiver and evaporator disposed in the closed fluid circuit path, and the closed fluid circuit path including a condenser and compressor. These systems also include a modulation capacity control circuit configured to selectively divert refrigerant vapor flow to the condenser from the compressor by diverting a portion of refrigerant vapor flow (diverted flow) from the compressor to the refrigerant receiver in accordance with cooling capacity demand.

Abstract: A refrigerator appliance, as disclosed herein, may include a cabinet, a door, a dispensing assembly, an ice-making assembly, and an ice storage bin. The door may define a dispenser recess having a transverse opening extending vertically from a top recess end to a bottom recess end and laterally from a first recess side to a second recess side. The dispensing assembly may be positioned within the dispenser recess and define an ice delivery passage. The ice-making assembly may be attached to the cabinet. The ice storage bin may include a bin body defining a storage cavity. The bin body may be selectively mounted to the door within the dispenser recess to receive ice from the dispensing assembly. The bin body may extend vertically from the top recess end to the bottom recess end and laterally from the first recess side to the second recess side.

Abstract: A refrigerator include: an inner case having a storage chamber; a thermoelectric module including a thermoelectric element and a cooling sink; a fan configured to circulate air, to the storage chamber; a fan cover configured to cover the fan and having an upper discharge hole, a lower discharge hole, and an inner suction hole formed between the upper discharge hole and the lower discharge hole; a first receiving member disposed in the storage chamber; and a second receiving member disposed over the first receiving member to be spaced apart from the first receiving member. At least a portion of each of the inner suction hole and the lower discharge hole faces a portion between the first receiving member and the second receiving member, and at least a portion of the upper discharge hole faces a portion between a top surface of the storage chamber and the second receiving member.

Abstract: Embodiments disclosed herein are directed to a shelf and shelving system for a refrigerator door having a door liner with opposing side walls, where each side wall includes a row of ditch steps. The shelf or shelves includes a gap wall at each end of the shelf. A switch is positioned above each gap wall. Each switch includes a handle, a mounting rod and a biasing member for biasing a long component of the handle outwardly away from the gap wall such that an engagement surface of the long component will engage a ditch step and thereby secure the shelf in place within the refrigerator door. The switch is actuatable by a user to allow for vertical adjustment of the shelf along the rows of ditch steps or to remove the shelf therefrom.

Abstract: A cooler access control system locks a cooler when occurrence of an event is detected that requires limiting access to the inside of the cooler. Examples of such events include the loss of power to the cooler for a predetermined period of time, the opening of the cooler door for longer than an allowed time, the loss of functionality of a temperature probe and others. In an embodiment, a service mode is supported wherein the door is left unlocked despite the occurrence of such an event, to allow a stocker or other personnel to leave the cooler door open while stocking the cooler with product.

Abstract: The present disclosure relates to a refrigerator and a transparent panel assembly for a refrigerator. The transparent panel assembly for a refrigerator comprises: a front panel defining at least a part of a front appearance of a refrigerator door and made of a glass material; a rear panel defining at least a part of a rear appearance of the refrigerator door and made of a transparent material; and an intermediate member connected between the front panel and the rear panel and made of a transparent plastic member, wherein the intermediate member comprises: an edge portion having both ends connected to a screening area formed at peripheries of the front panel and the rear panel; and a partition portion formed to cross an inner surface of the edge portion to partition a gap between the front panel and the rear panel to thereby form a sealed insulation layer.

Abstract: Provided is a refrigerator having a supporting frame whose installation structure is enhanced. The refrigerator includes an inner case defining a storeroom and having a projection formed to protrude to the inside of the storeroom, a drawer arranged to be inserted or pulled out from the storeroom, and a supporting frame arranged in the storeroom to guide movements of the drawer, and installed at the projection, wherein the supporting frame includes a fixer arranged on a side of the supporting frame to prevent the supporting frame from deviating from the projection, the fixer being deformed when pressurized by the projection and restored to an original state when the pressure from the projection is released.

Abstract: The subject matter of this specification can be embodied in, among other things, a method for time shifting when a cold storage facility is cooled that includes determining a thermal model of a cold storage facility, obtaining an energy cost model that describes a schedule of variable energy costs over a predetermined period of time in the future, determining an operational schedule for at least a portion of a refrigeration system based on the thermal model, the energy cost model, and a maximum allowed temperature, and powering on the portion the refrigeration system based on the operational schedule, cooling, by the powered portion of the refrigeration system to a temperature below the maximum allowed temperature, reducing power usage of the powered portion of the refrigeration system based on the operational schedule, and permitting the facility to be warmed by ambient temperatures toward the maximum allowed temperature.

Abstract: An artificial intelligent refrigerator is disclosed. The artificial intelligent refrigerator includes: one or more first temperature sensor that senses refrigerating compartment-internal temperature in a refrigerating compartment of the refrigerator; one or more second temperature sensor that senses freezing compartment-internal temperature in a freezing compartment of the refrigerator; and a refrigerator processor that calculates a load accumulation amount for food put in the refrigerator on the basis of the refrigerating compartment-internal temperature or the freezing compartment-internal temperature, and performs a load correspondence operation using the calculated load accumulation amount.

Abstract: A refrigerator and/or freezer unit and system for storing, monitoring, and maintaining a supply of temperature sensitive pharmaceutical products in compliance with regulatory requirements. The unit contains compartments for each product type in multiple controlled temperature zones with sensors to track product status and content. In a system, each unit communicates with an application service provider to provide remote inventory management capability.

Abstract: Temperature-controllable container with vacuum insulation elements and with an interior space, which container comprises a wall with an opening for objects to be placed into the interior space, and a door element closing the opening, wherein transport elements are arranged on an outer surface of the container, which transport elements are designed to enable lifting by means of a transport vehicle, and wherein the container further comprises a temperature control unit which is designed so as to bring the interior space to a predetermined temperature T, wherein the temperature control unit comprises a heating/cooling unit operated via a solar energy device or a heating/cooling unit operated via a power supply network, and wherein a receptacle means for melt-storage elements or sample bodies is arranged in the interior space, which receptacle means is designed so as to position at least two melt-storage elements or sample bodies at a distance from each other.

Abstract: A main heat exchanger receives and partially condenses an effluent fluid stream so that a mixed phase effluent stream is formed. A primary separation device receives and separates the mixed phase effluent stream into a primary vapor stream including hydrogen and a primary liquid stream including an olefinic hydrocarbon. The main heat exchanger receives and warms at least a portion of the primary vapor stream to provide refrigeration for partially condensing the effluent fluid stream. The main heat exchanger also receives, warms and partially vaporizes the primary liquid stream. A mixed refrigerant compression system also provides refrigeration in the main heat exchanger.

Abstract: A nitrogen liquefier configured to be integrated with an argon and nitrogen producing cryogenic air separation unit and method of nitrogen liquefaction are provided. The integrated nitrogen liquefier and associated methods may be operated in at least three distinct modes including: (i) a nil liquid nitrogen mode; (ii) a low liquid nitrogen mode; and (iii) a high liquid nitrogen mode. The present systems and methods are further characterized in an oxygen enriched stream from the lower pressure column of the air separation unit is an oxygen enriched condensing medium used in the argon condenser.

Abstract: The present disclosure provides an energy-efficient process for preparing nitrogen and oxygen for a glass melting furnace. A device required by the process includes a filter, a turbine air compressor, an air pre-cooling unit, alternately used molecular sieve adsorbers, an electric heater, a main heat exchanger, a rectifying tower I, a main condenser-evaporator I, a rectifying tower II, a main condenser-evaporator II, a rectifying tower III, a main condenser-evaporator III, a supercooler, an expander I and an expander II. The three rectifying towers are used to prepare a low-pressure nitrogen product and an oxygen product with a certain pressure at the same time. The oxygen product with a certain pressure is used for oxygen-enriched combustion for the glass melting furnace, and the low-pressure nitrogen product is used as shielding gas of a tin bath.

Abstract: A method of manufacturing ceramic tape includes a step of directing a tape of partially-sintered ceramic into a furnace. The tape is partially-sintered such that grains of the ceramic are fused to one another yet the tape still includes at least 10% porosity by volume, where the porosity refers to volume of the tape unoccupied by the ceramic. The method further includes steps of conveying the tape through the furnace and further sintering the tape as the tape is conveyed through the furnace. The porosity of the tape decreases during the further sintering step.

Abstract: A method of producing a graphite-containing refractory within which carbon fiber bundles are placed, the graphite constituting 1% to 80% by mass, the method including a bundling step of bundling carbon fibers to form the carbon fiber bundles; a mixing step of mixing a refractory raw material with graphite to prepare a graphite-containing refractory raw material; a pressing step of pressing the graphite-containing refractory raw material in which the carbon fiber bundles are placed to prepare a formed product; and a drying step of drying the pressed product, wherein the bundling step includes bundling 1000 to 300000 of the carbon fibers with a fiber diameter of 1 to 45 ?m/fiber to form carbon fiber bundles 100 mm or more in length.

Abstract: Methods and systems are provided for heat exchangers including a first outer plate, a second outer plate, and an intermediate plate. The intermediate plate is positioned between the outer plates. Fluid flow passages are formed between the intermediate plate and each of the outer plates.

Abstract: The invention relates to a heat exchanger for vaporizing a coolant fluid by heat exchange with a calorigenic fluid, said exchanger comprising several parallel plates defining a plurality of passages between them which are suitable for the coolant fluid or calorigenic fluid to flow, a first wave and a second wave extending between two successive plates so as to define a plurality of channels within the same passage, said first and second waves comprising two adjacent edges, at least one assembly member extending from one edge to the other so as to connect the waves to one another. According to the invention, the assembly member is forcibly engaged in at least one part of a channel of the first wave on one hand, and in at least one part of a channel of the second wave on the other hand.

Abstract: The present invention relates to a method of manufacturing a cooling device using a heat pipe in which, using casting, the heat pipe is embedded inside a housing, and the method includes a filling step in which a predetermined support member is filled inside a pipe to prevent deformation of the pipe by a pressure of a melt being injected into a cavity of a mold that is closeable, a pipe seating step in which the pipe filled with the predetermined support member is seated in the cavity, a melt injecting step in which the melt is injected into the cavity to surround the pipe, a cooling and withdrawing step in which the injected melt is cooled and a molded product is withdrawn, an injecting step in which a working fluid is injected into the pipe through an injection end, and a finishing step in which, after the injecting step, the pipe is sealed.

Abstract: An example sensor bracket assembly can include one or more cold plates forming a core bracket structure, wherein the core bracket structure and the one or more cold plates provide structural support for the sensor bracket assembly; a housing enclosing the core bracket structure; one or more sensor mounts for mounting one or more sensors on the sensor bracket assembly; and one or more attachment portions for attaching the sensor bracket assembly to a body of a vehicle.

Abstract: A firearm includes a barrel having a breech end. A receiver is engaged with the breach end of the barrel and defines a chamber. A vent path is through the barrel downstream from the breech end. A latch is downstream from the vent path. A bolt is at least partially inside the chamber. The bolt has a locked position to prevent the bolt from moving away from the breech end of the barrel and a released position that allows the bolt to move away from said breech end of the barrel.

Abstract: An AR-pattern firearm comprises an upper receiver, a housing positioned above the upper receiver and containing a recoil spring assembly, a bolt carrier assembly positioned in the upper receiver, and a bridge plate operably connecting the bolt carrier assembly to the recoil spring assembly. Discharge of the firearm causes rearward movement of the bolt carrier assembly out of battery and hence rearward movement of the bridge plate which stores energy in the recoil spring assembly, whereupon the stored energy in the recoil spring assembly causes the bolt carrier assembly to move forward back into battery.

Abstract: A trigger activated arm may use a piston moving within a cylinder to dampen gun bolt speed. In some embodiments, gun bolt motion increases pressure within the cylinder bore to dampen rearward gun bolt speed. The pressure may be high enough to unseat the cylinder creating a vent that cylinder fluid exits. In other embodiments, gun bolt motion decreases pressure within the cylinder bore to dampen forward gun bolt speed.

Abstract: A rifle with an auto-loading mechanism having a gas chamber with a guiding tube connected to a gas adapter, and a piston assembly including an impact damper, a piston slidingly movable within the gas chamber, a guide fixed to the piston at one end and provided at its other end with a blind hole, a fixed piston slidingly movable at one end within the blind hole of the guide and fixed to the impact damper at the other end, a helical spring arranged within the blind hole of the guide and a return helical spring arranged around the guide in a way to lean against a stop in the guiding sleeve with one end and against the impact damper with the other end, wherein the gas chamber is arranged on the rifle barrel in the area of the barrel receiver. The advantage of the rifle lies in that it allows for more accurate shooting, has lower weight and less recoils.

Abstract: The inventive technology is directed to a bolt hold-open system configured to lock the bolt of an AK-47 firearm, or variants of the AK-47, in an open position after the last cartridge in a magazine has been ejected.

Abstract: Trigger assembly for use in a weapon. Components of the trigger assembly include a spring, a hammer, a disconnector, a trigger and other components related to a trigger assembly.

Abstract: A recoil assembly for a rifle includes a barrel assembly, a bolt, bolt actuator, and a buffer assembly. The barrel assembly includes a barrel secured to a barrel extension. The barrel assembly is configured to be movably received through the fore end of a receiver and to move axially relative to the upper receiver when the rifle is fired. The barrel extension is coupled to a hydraulic buffer assembly located below the barrel extension and counteracts recoil forces acting on the barrel extension when the rifle is fired. An op-rod spring is coupled to an op rod extending from a gas piston assembly on the barrel. The op-rod spring counteracts recoil forces acting the bolt actuator when the rifle is fired.

Abstract: A cranking mechanism preferably includes a planetary gear, a drive shaft, a one way bearing, a clutch assembly, and at least one drive unit. The clutch preferably includes a clutch pressure plate, a flywheel, friction surfaces and at least one friction plate. Each drive unit includes a carrier, a spool and a flywheel. The one way bearing and the clutch assembly are axial on the drive shaft. A pressure locking nut is threaded on to a threaded end of the crank shaft to exert pressure on the clutch assembly. The sun gear is fixed on the drive shaft. The at least one drive unit is axial with the drive shaft, and fixed with the carrier of the planetary gear set. The pressure locking nut is tightened against the clutch assembly to frictionally engage the drive shaft with the at least one drive unit.

Abstract: A device for illuminating BBs emanating from an airsoft gun has a lighting element positioned proximate a breech area of the airsoft gun to illuminate the breech area. A switching device is coupled to the lighting element. A power source is coupled to the switching device and the lighting element.

Abstract: Example implementations relating to a deep concealment holster assembly are disclosed herein. In one particular implementation, a holster specifically designed and/or structured for a waist belt concealment may be adapted for a deep concealment.

Abstract: This invention herein described is a firearm mountable, illumination and projection system for projecting, detecting and/or receiving electromagnetic radiation (waves) from across the electromagnetic spectrum by utilizing a variety of technologies such as LED's, Infrared Illuminators, Laser Emitters, and FLIR sensors (examples not limitations). This invention, herein described, is unique in that the embodiment(s) for Illumination and Projection are separate, unique, and isolated (distally) from the embodiment providing the necessary power (Current, Voltage, Electromotive Force) for the illumination and/or projection of electromagnetic radiation.

Abstract: A long-range optical device (1), in particular a telescopic sight, comprising a reticle (6), the position of which is adjustable, and an associated reticle adjustment device (7) for adjusting the position of the reticle (6), a magnetic device (16) comprising a plurality of magnetic elements (16a, 16b), a detection device (18) associated with the magnetic device (16), wherein the magnetic device (16) is mounted so as to be movable relative to the detection device (18) and/or the detection device (18) is mounted so as to be movable relative to the magnetic device (16), wherein the detection device (18) is configured to detect the relative movements between the magnetic device (16) and the detection device (18) and, based on detected relative movements between the magnetic device (16) and the detection device (18), to generate reticle position information describing the position of the reticle (6).

Abstract: A zoom cell has a main zoom cell body having a central axis, at least two fingers extending from the main zoom cell body parallel to the central axis, and at least two grooves separating the at least two fingers. A zoom cell system has at least two zoom cells disposed in an erector tube, with the fingers of the at least two zoom cells pointed towards one another, with the at least two zoom cells positioned such that the fingers of a first of the at least two zoom cells align so as to correspond with at least one of the at least two grooves of the other of the at least two zoom cells.

Abstract: An automated weapon system [preferably a human transported weapon] is comprised of a barrel, a targeting subsystem, a computational subsystem, a positioning subsystem, and, a firing subsystem. The barrel is utilized for propelling a fired munitions as aimed towards an area of sighting. The targeting subsystem identifies a chosen target in the area of sighting. The computational subsystem, responsive to the targeting subsystem, determines where the chosen target is and where the barrel needs to be aimed so that the munitions will strike the chosen target. The positioning subsystem adjusts the aim of the munitions responsive to the computational subsystem. The firing subsystem, fires the munitions at the chosen target responsive to the positioning subsystem. In one embodiment, the system is further comprised of an additional linked automated weapon having a separate barrel, separate munitions, a separate positioning subsystem, and a separate firing subsystem.

Abstract: A modular illumination and aiming apparatus, a preferred embodiment of which includes an optical head module, mounting module, and an end cap module. The modular illumination and aiming apparatus is configured to be quickly and intuitively adjusted by a user in response to changing target and environmental conditions. The modular illumination and aiming apparatus is configured to be ergonomically supportive such that a user may maintain a consistent firing grip while activating the illumination and aiming functions. The optical head module is configured to allow the user to change radiation types by adjusting an end cap. The alignment mechanism in the optical head module for the radiation source and optics is configured to provide a robust and zero-play optical mount in order to resist recoil and general physical shock.

Abstract: A blast resistant container includes a rigid outer cylinder, a rigid inner cylinder and at least one pumice brick. The rigid inner cylinder has a longitudinal axis. The at least one pumice brick is within the interior of the rigid inner cylinder.

Abstract: A device and a method of anti-unmanned aerial vehicle based on multi-camera tracking and positioning, including: a bracket, defined a center, a circumference surrounding the center and a central axis passing through the center; at least three cameras, the cameras are evenly distributed and inclined outwardly on the circumference of the bracket, and center lines of view of the cameras forms an inverted cone; a directional antenna, configured to be arranged on the central axis of the bracket; an electromagnetic module, configured to be coupled to the directional antenna; a pan-tilt, connected to the center of the bracket and configured to drive the bracket to rotate; and a control unit, configured to control the pan-tilt to track a target and lock on to the target according to the video image provided by the cameras, such that the electromagnetic module is manipulated to attack the target.

Abstract: The invention provides a suspended catamaran target boat, including a deck, a suspension structure and two buoyancy units, the suspension structure is connected to upper sides of the two buoyancy units, and the deck is mounted on the suspension structure; the suspension structure includes at least two suspension assemblies including an upper base, a lower base and two support rods. The support rods are hinged between the upper base and the lower base, and the upper base, the lower base and the two support rods form a four-bar linkage mechanism, where a shock absorber and a restricting mechanism are installed between the upper base and the lower base. The deck is provided with a main controller, an acceleration sensor and a heel sensor, and the main controller is respectively electrically connected with the acceleration sensor, the heel sensor and each of the restricting mechanisms of the two suspension assemblies.

Abstract: An opto-thermal laser detonator uses resonantly absorptive tuned nano-material associated with secondary explosives for optical absorption and initiation by an integral laser diode. The opto-thermal laser detonator includes main explosive material; resonantly absorptive tuned nano-material; secondary explosive material, wherein the resonantly absorptive tuned nano-material and the secondary explosive material are associated to form associated material made of the resonantly absorptive tuned nano-material and the secondary explosive material; and a laser diode operatively connected to the associated material, wherein the laser diode initiates the associated material which in turn initiates the main explosive material.

Abstract: A circuit for controlling the firing of an exploding-foil pyrotechnic component including at least one capacitor and switch means, the capacitor being connected to the pyrotechnic component by an array of at least three diodes connected in series and in a direction that prevents the capacitor from discharging, the sum of the reverse voltages of these diodes being greater than the maximum voltage that can be delivered by the capacitor, the switch means including at least two field-effect transistors associated with the array of diodes.

Abstract: A mechanism for extraction caseless ammunition, the mechanism for extraction including a receiver (84) interacting with the lid of the receiver (85); lock frame (86) which interacts with the lid of the receiver; bolt (88) made in the lock frame; a conical bushing (93) installed inside the bolt through the firing pin (89); an extractor (95), wherein lock frame is made with a front ledge (87); on the front end of the firing pin the conical part (90) is made; conical bushing (93) is made with interior ledges (94); a shaft (103) with a circular groove (104); the rear part (102) passes into the lower ledge (106) which has a front inclined area (107) and a rear horizontal area (108) and the lower ledge (106) passes into the upper ledge (109) which has a front inclined area (110), an upper horizontal area (111) and a rear inclined area (112).

Abstract: An archery shaft is disclosed herein. The archery shaft, in an embodiment, includes an elongated member having an outer surface. The archery shaft also includes a formation arranged at least partially around the outer surface of the elongated member. The formation has a braided characteristic. Furthermore, the formation has a plurality of reinforcement fibers.

Abstract: A nock for an archery arrow or bolt. The nock includes a radial indention configured to be engaged by a biased retainer of a trigger mechanism of a crossbow to retain the arrow or bolt in a desired position relative to the trigger mechanism and/or a bowstring. The radial indention may optionally comprise a groove defined generally continuously around a circumference of the nock. The radial indention is exposed when the nock is coupled with an arrow or bolt such that the radial indention may be engaged by a biased retainer within the trigger mechanism. The nock may further include a generally planar rearward bearing surface configured for being engaged by a bowstring. The nock of the present invention may be suitable for use with a multiple-shot crossbow or a single-shot crossbow. Other aspects of the present invention are directed to a projectile, a projectile retention system, and a crossbow.