Abstract: A clutch assembly for a turning gear includes an overspeed clutch, an output shaft, and a centrifugal clutch. The overspeed clutch is disposed at the input shaft. The output shaft is in mechanical communication with the input shaft via the overspeed clutch. The centrifugal clutch is disposed at a portion of the output shaft.

Abstract: A rotary flow inducing device having a rotary flow inducing blade and a protection mechanism including a trigger to move the protection mechanism between an operational flow configuration and a protective no-flow configuration with respect to the rotary flow inducing blade.

Abstract: A wind power system (1) for generating power is proposed, comprising a rotor which is axially flowed through, is rotatably held on a shaft (2) and is provided with blades (3), as well as a guide device (5) which accelerates the air flow through the rotor (4). In order to provide advantageous conditions for generating power it is proposed that the guide device (5) consists of several flow conduits (6) tapering in the direction of flow, which conduits are arranged on the rotor (4) in a distributed way in the manner of a rim around the shaft (2), that the blades (3) are associated with one flow conduit (6) each and that the rotor (4) comprises an outside jacket (7) enclosing the same.

Abstract: The present invention discloses a wind driven power generator.

Abstract: An impeller, and impeller and rotor assembly, for use with a permanent magnet motor that provide uni-directional rotation. The impeller and rotor assembly includes an interconnecting arrangement and a locking arrangement that permit continuous rotation in a first direction and prevent continuous rotation in a second opposite direction.

Abstract: A fan is modified by replacing its rigid rotor shaft by a flexible shaft so the normal operating speed range is above the first transverse critical speed. During run-up, the assembly of the fan impeller 12 and the drive shaft 11 is accelerated rapidly through the first critical speed at which the peak transverse vibrations could be encountered, and during run-down the shaft 11 is braked to minimize the same exposure to transverse vibrations. The use of a more flexible fan drive shaft of smaller diameter, allows a higher fan operating speed to be used without risk of detrimental shaft aerodynamic chokage effects, and the utilization of the existing fan foundation.

Abstract: A wind power system includes a rotary drive, used in conjunction with a mechanical and self-energizing coupling system. The rotary drive can be used as a wind power system in all areas. The electromagnetic coupling system can be used in all industrial areas, in all areas and types of vehicle technology, and in all electrical engineering areas. The combination of a wind power system with a rotary drive with mechanical and self-energizing coupling system indicates that the wind force can be utilized more effectively than in the case of conventional wind-driven rotors, irrespective of the physical size. This is achieved by virtue of the blade arrangement and the special design of the housing. The self-energizing coupling system furthermore has the physical advantage that the magnet is combined in one space with the iron core and, on the other hand, a short-circuited coil is energized. The current for the electromagnetic coupling may also be taken directly from the generator stage.

Abstract: A turning device for compressed air tools. which is operated by a compressed fluid, is provided with a housing and with a rotor, which is rotatably arranged in a front housing part and into whose turbine element the fluid, which is under pressure, can flow, has a braking arrangement and a switch for the compressed fluid. The switch which is operatively connected with the braking arrangement and is arranged on a rear housing part in line with a compressed fluid supply conduit. Such a turning device requires fewer components and can be stopped in a simpler and faster way by a fluid switch, in the form of a sliding switch, which encloses the rear housing part in the area of the supply conduit and is provided with axially oriented control pins, which are connected, fixed against relative displacement, with a brake disk of the braking arrangement.

Abstract: An improved oil seal is provided for sealing passage of a rotatable shaft through an end wall of a bearing housing in a turbomachine or the like, wherein the shaft is rotatably supported within the bearing housing by oil-lubricated bearings. The improved oil seal comprises a dynamic oil-air separator and a slinger rotor mounted on the shaft for rotation therewith, the slinger rotor having an outwardly extending slinger ring with an outboard seal face with radially oriented slots and a circumferential groove or grooves.

Abstract: An air turbine starter with an improved seal assembly is provided. A fluid conduit or channel allows higher pressure fluid into one side of a bearing seal. For example, the seal assembly may include a face seal, and a second seal forming a chamber therebetween and a flow passage opens into the chamber for exposing the chamber to the higher pressure.

Abstract: A turbine controls testing device is disclosed that can be adapted to test the control systems of most turbine rotors without the use of steam. The turbine controls testing device comprises an operator control system, a drive motive power assembly and a purge gas assembly. The novel device controllably spins, accelerates, and decelerates a turbine with a relatively high level of precision, minimizing the likelihood that, in the event an overspeed mechanism malfunction occurs, the turbine will be damaged as a result of sonic velocity or any other mechanical failure.

Abstract: A stator has a pocket portion (8) of a notch type resin-made stator, in which strength of an outer corner R (12b) provided in the pocket portion (8) is increased to thereby prevent the resin-made stator body (1) from being broken from the outer corner R (12b). A stator has a pocket portion (8) encasing a strut 9 of a notch type one-way clutch (5). The pocket portion (8) is provided in a stator body (1) made of resin, and corner Rs (12a, 12b) are provided on both inner and outer sides of a strut engaging surface (13) in the pocket portion (8). The outer corner R (12b) is formed to be larger than the inner corner R (12a).

Abstract: A hydro-electric generator for producing electricity in areas of flowing water. The hydro-electric generator includes a flotation device. An electric generator is mounted on the floatation device. A paddle wheel is rotatably mounted to the floatation device. The paddle wheel is mechanically coupled to the electric generator. The floatation device is anchored in an area of flowing water such that a current rotates the paddle wheel and electricity is produced.

Abstract: An improved oil seal is provided for sealing passage of a rotatable shaft through an end wall of a bearing housing in a turbomachine or the like, wherein the shaft is rotatably supported within the bearing housing by oil-lubricated bearings. The improved oil seal comprises a dynamic oil-air separator and a slinger rotor mounted on the shaft for rotation therewith, the slinger rotor having an outwardly extending slinger ring with an outboard seal face with radially oriented slots and a circumferential groove or grooves.

Abstract: Fan brakes for decelerating blower impellers particularly for modular equipment enclosures are described. A module includes a blower having an impeller with a plurality of blades. The brake engages the impeller body or blades when the module is at least partially removed from the enclosure and disengages the impeller when the module is inserted into the enclosure. One brake includes an arm coupled to a braking surface. The arm applies the braking surface to the impeller when disengaged by a cam and retracts the braking surface from the impeller when engaged by the cam. A solenoid may be used in lieu of a cam for directly or indirectly applying the braking surface.

Abstract: A windmilling brake system for a turbine engine includes a brake drum (14) on an interior surface of an engine rotor. The drum circumscribes a brake unit (37) that includes a brake ring (38) with brake shoes (42) each connected to the ring by respective springs (44). A leg (45) extends from each shoe and toward the ring. The ring is sandwiched axially between bolting flanges (28, 29) on forward and aft carrier portions (24, 25) of a two piece, variable stiffness, dual load path rotor bearing support. Nonsacrificial fasteners secure the ring to one of the flanges while frangible fasteners (52) secure the flanges to each other. The frangible fasteners also extend through an eye (47) in each leg to deflect the springs and hold the brake shoes in an armed state out of contact with the drum. Upon being exposed to abnormal imbalance loads, the frangible fasteners fail in tension to disable one of the two load paths.

Abstract: A portable working machine provided with a centrifugal air blower, which is featured in that a prime mover (50) for driving the air blower (20) is mounted via a supporting coupling member (30) on a volute case (22) of the air blower (20) which is mounted in an upright state; and that an air inlet port of the air blower (20) is positioned on the side of the volute case (22) which is closer to the prime mover (50).

Abstract: A damping coupling is provided to reduce the oscillations of the yawing device of a wind power plant. The damping coupling transmits forces from a driving device to a yaw drive, and the damping coupling is arranged and positioned in such a way that the transmitted moment is dependent on the difference in the rotational speeds between the input and the output shafts of the coupling. The damping coupling is preferably a hydrodynamic coupling.

Abstract: A high bypass ratio turbojet engine comprising a fan rotated by the shaft of a low pressure turbine via a speed reducer is provided with a thrust reverser device by providing the speed reducer with first and second epicyclic gear trains which are mounted in parallel between the low pressure turbine and the fan and which are arranged in such a way as to drive the fan in a first direction of rotation when the engine is operated in a direct thrust mode, and to drive the fan in the opposite direction of rotation when the engine is to be operated in the reverse thrust mode.

Abstract: A fluid power storage device is provided in which, the prime mover directly or through a slow-down gear train winds up a spring device having a latch attached therein. The spring device can be a spiral spring or simply a rubber band. When the stored up energy is great enough, an adjustable stopper automatically releases the spring device being latched. The spring device in turn, releases the stored energy which then activates a mechanism or drives an electric generator. After a certain amount of energy stored up is released, the latch will automatically be caught by the stopper. Hence the mechanism or the electric generator will be stopped and the fluid power storage device starts to store up energy again for the next release of the spring device.

Abstract: In a torque converter, in order to reduce the cost, simplify the manufacturing process and ensure the centering precision of of the stator relative to the outer race of a one-way clutch, the stator and the outer race of the one-way clutch have first engaging surface portions preventing relative rotation therebetween and second engaging surface portions providing concentricity therebetween. The first and second surface portions are axially offset from each other.

Abstract: Manual rotation of a turbomachine rotor in order to bring the blades of the rotor one by one in front of an endoscope to check the blades is effected by a shaft which is rotatably connected to the rotor and which may be, for example, a shaft of the auxiliary equipment of the turbomachine, the shaft being manually rotatable by a driving shaft which is mounted in an opening in the casing housing the shaft and which is engageable with the shaft by self-disengaging coupling, a seal being provided between the driving shaft and the casing.

Abstract: A vertical axis wind turbine is supported by a frame held in place by an encircling series of crescent-shaped tubular deflector vanes. The vanes widen towards the turbine core, concentrating the wind. The wind is trapped momentarily on entering the turbine cavities. Air can be supplied to such cavities from a compressed air source driven by wave action on a body of water.

Abstract: A torque converter stator made by injection molding of plastic material includes a metallic one-way clutch outer race which is insert molded within the stator hub. A plurality of recesses forming lubricant passages extend through the wall of a radial flange of the hub. The lubrication recess (30) is defined by a part-cylindrical outer wall (32) and a pair of planar side walls (34) spaced apart by a distance d. The juncture of the outer wall (32) and the side wall (34) is filleted to form a rounded corner (36) having a radius of curvature R1. To relieve the weld line (60) from concentration of residual stress due to post-molding shrinkage while avoiding stress concentration at the rounded corners (36), the ratio R1/d is selected to be 0.18-0.35.

Abstract: A braking mechanism for a rotary apparatus having a housing adapted to receive a pressurized fluid and a rotor rotatably mounted in the housing. The braking mechanism enables the rotor to rotate in the housing in response to the receipt of the pressurized fluid and inhibits the rotor from rotating in the absence of the receipt of the pressurized fluid.

Abstract: An exhaust gas turbocharger for an internal combustion engine is described, in the turbine housing of which there is arranged upstream of the turbine wheel a turbine guide wheel which is mounted rotatably relative to the turbine wheel. In order to be able to improve the response of the internal combustion engine after a positive load change without any impairment of the overall efficiency of the internal combustion engine, it is proposed to provide at least one braking device which reduces the speed of the turbine guide apparatus in higher load.

Abstract: A coolant pump system driven initially by an electric motor in-line with the pump shaft to the pump housing incorporates a ram air-assisted cooling system. The ram air-assisted cooling system includes an electric motor whose rotating shaft drives the primary fan member. A second fan member is located about and connected to the periphery of the primary fan member and is rotated by high velocity air streams purposefully directed at the secondary fan blades. The air which drives the secondary fan member is preferably gathered by one or more air inlet funnels. Typically, two air inlet funnels are equiangularly disposed adjacent the periphery of the secondary fan blade members so that a balanced current of air is swept across the secondary fan blades. A shroud extends over the secondary fan blade members to force the inlet air over the fan blade members.

Abstract: A coolant pump system driven by an electric motor mounted in-line with the pump shaft to the pump housing. The system minimally includes a pump body having a bore therein, a coolant pump impeller, a pump shaft passing through the bore and having the impeller mounted on one end thereof, and a bearingless seal shaft assembly disposed in the bore which prevents coolant from leaking out of the body around the rotating pump shaft. The outer end of the pump shaft and the drive shaft of the electric motor preferably include a quick-disconnect coupler which allows the two shafts to be repeatedly coupled and uncoupled without damage and without tools. This coupling mechanism may take the form of a socket with bayonet slot on one shaft and mating pin on the other shaft that fits in the slot. A face-mounted electric motor is rigidly but removably bolted to the pump housing, and its drive shaft provides complete support for the pump shaft which rotates therewith.

Abstract: In an open state of a valve, when a valve outside sleeve is rotated in the rear portion of a housing, a valve inner sleeve is moved forward to close a fluid channel, thus stopping supply of compressed driving air. Simultaneously, a front end of the valve outside sleeve is moved forward while it abuts against the rear surface of a retainer. Therefore, brake rods biased by compression coil springs are also moved forward, and front surfaces of the brake rods are abutted against a brake disk to effect braking, thereby immediately stopping rotation of a rotor. The urging force applied on the brake disk is the compression force of the compression coil springs.

Abstract: A brake mechanism used in a vehicle comprises: a gear connected to an engine of the vehicle; a casing; a radial compressor disposed in the casing and having an impeller, an impeller shaft extending from the back of the impeller in the casing, a suction port, and an outlet port for sucking in air from the suction port, compressing it within the casing, and delivering it from the outlet port by the impeller; a gear that connects the impeller shaft with the engine output shaft gear; a shaft support for rotatably supporting the impeller shaft; and a recess formed in the back of the impeller for accepting the shaft support. The arrangement substantially raises the resonant vibration frequency of the impeller shaft due to a coupling imbalance derived from the impeller construction so that resonant vibration is prevented during ordinary engine operation since the length of the impeller shaft between the point of rotational support and its rear end is substantially elongated whereas the overhang, i.e.

Abstract: An air turbine starter for use aboard aircraft includes a dual range power train and a clutch automatically shifting between the ranges according to the use being experienced by the starter. Main engine starts may be achieved more quickly, while ground check out of aircraft systems using the starter to power main engine accessory devices via the engine gear box may be performed with better power input to the accessories and improved efficiency.

Abstract: A gas turbine engine is provided with a braking device for stopping the compressor drive turbine if a common shaft interconnecting the turbine and compressor rotors breaks, the braking device including a conical ring carried by the turbine rotor at its downstream end and a structural member of a generally conical shape carried by the upstream end of the turbine exhaust casing such that the ring will frictionally interlock with the structural member if the shaft breaks.

Abstract: A portable electric appliance including a fan device comprising a rotatable blade assembly and an electrical motor operatively coupled thereto; a standard having an upper end fixed to the fan device; a pedestal base; a coupling including an upper member joined to a lower end of the standard and a lower member pivotally coupled with the upper member and joined to the pedestal, the upper member being freely demountable from the lower member; a manually operable latch for preventing demounting of the upper member from the lower member; and a positioning mechanism for selectively fixing the relative angular positions of the upper and lower members.

Abstract: A torque limiting decoupler shaft transmits driving torque in a first sense without torque limiting action. However, torque applied to the shaft in a reverse sense opposite the driving torque results in an axial separating force between two portions of the decoupler shaft. When the reverse torque reaches a certain level a frangible tensile bar member fractures to permit decoupling of the shaft portions. A component of the shaft prevents undesirable recoupling of the shaft portions while also insuring that the relatively rotating portions of the shaft do not flail. An air turbine starter includes such a decoupler shaft.

Abstract: A temperature activated fan assembly preferably for an electric motor. The assembly includes a fan, a torque transfer means engagable with the fan for transferring torque to the fan and a first member which expands in response to a temperature increase. The expansion of the first member causes the torque transfer means to engage the fan. The first member is situated within the motor such that the first member causes the fan to operate when a critical temperature in the motor is reached. The first member can be fabricated as a rod or coil from a material having a suitably high coefficient of thermal expansion. The first member can also be fabricated from a memory material.

Abstract: A pneumatic system is disclosed for regulating the acceleration and running speed of an air turbine and alternator used in electrostatic spray apparatus having a self-contained electrical power supply. The air turbine includes a rotor which is arranged to be biased in a first direction of rotation by a flow of impinging drive air and in a second opposite direction by a flow of impinging brake air. The flows of air cooperatively result in rotation of the turbine in a desired direction of operation and enable a minimized period of acceleration for a predetermined running speed.

Abstract: A multi-stage turbine has an inflow disc pack that directs motivating fluid to an outflow disc pack on the same shaft. The packs are fitted to rotate between plates that web a turbine casing interior and fluid entry into the casing to the inflow pack is via nozzles in a ring assembly fixed to the casing. Each disc pack is made up by spaced apart discs with fences that guide the motivating fluid first through the inflow pack and then the outflow pack. A central passageway in the packs and adjacent the shaft communicates fluid inflow to outflow. Fluid exhaust is through exits at the casing bottom. In one version, the disc packs are conical and when seen from the side, the packs with webbed plates are X configured in section. In another version, the inflow pack is flat, the outflow pack conical and the casing of both versions are configured to provide low losses and maximum strength. The nozzles can be convergent-divergent in a plenum located adjacent the inflow pack circumference.

Abstract: The segments (1) of the braking track (112) fixed to the rotor of an alternator driven by a water turbine are cooled by circulating water by means of a thermosiphonic effect from tanks (5) which are also fixed to the rotor.Application to the security of safety water-driven turbo-alternator units.

Abstract: A propeller brake for a twin spool turbo-prop engine which permits the propeller to be locked in a stationary position with the engine running is disclosed. The propeller brake has a hydraulically actuated friction brake and hydraulically actuated locking mechanism rotatably connected to the engine spool turning the propeller. The friction brake stops the propeller from rotating in response to an external command. A hydraulic signal indicating the propeller has stopped rotating actuates the mechanical lock holding the propeller in a stationary position. A safety latch prevents the mechanical lock from being actuated in event of a hydraulic pressure or engine failure in flight.

Abstract: The present application discloses an electric fan apparatus comprising a fan, a wind direction shifting plate disposed in front of said fan and adapted to be rotated by the pressure of a wind generated by said fan, a rotary shaft disposed at the center of said wind direction shifting plate and adapted to be rotated integrally with said wind direction shifting plate, a speed governor mechanism interlocked with said rotary shaft and a housing box for housing said speed governor mechanism.With said wind direction shifting plate rotated, a wind may be provided in a wide range. Provision is made to improve the durability of said speed governor mechanism, which is formed with a gear mechanism and a blade. Said housing box contains a liquid into which at least a portion of said gear mechanism is immersed, so that said wind direction shifting plate is rotated at a substantially constant low speed.

Abstract: A shaft drive alternately for both directions of rotation, comprises, a shaft rotatably supported on bearings having first and second turbines connectable thereto, each including a respective first and second turbine wheel freely rotatable on the shaft in respective opposite first and second directions. The turbine wheels are driven by fluid which rotates the wheels in a selected direction and, in addition, displaces the turbine wheels so that a friction disc carried thereby is engaged with a respective first and second clutch to connect it to the shaft to impart the selected direction of rotation. When the turbine is stopped by not directing the fluid into the blades, in which case the clutch mechanism is moved out of engagement and the turbine wheel may run free of the shaft, the second turbine wheel may be connected in a similar manner by effecting engagement of the associated second clutch with the shaft when the fluid is directed to the second turbine for rotating the turbine wheel.

Abstract: In a hydroelectric facility, a vertically mounted rotatable shaft is connected to a motor-generator and carries a pump-turbine with a supplying pump disposed below and immersed in water, the supplying pump disengaging from the shaft when the pump-turbine is driving the motor-generator and engaging the shaft when the motor-generator is driving the pump-turbine and supplying pump, thereby providing a two-stage pumping mode and a single-stage generating mode.

Abstract: A pump assembly to be used for mining, and the like, is supported on rope-like members (32, 110, 112, 140, 181,190) of an endless conveyer. In one type of embodiments a channel-shaped mounting member (20, 72, 138, 164, 192) of the pump assembly straddles the rope-like support members and allows the weight distribution of the pump assembly to cause a drive wheel (16, 68, 142, 146, 196) of the pump assembly to come into contact with the endless conveyer (28, 144, 198) to thereby drive a pump (18, 76, 134, 160, 182) of the pump assembly. In a particular one of these types of embodiments the pump (134) is mounted inside the rope-like support member (140) to urge the drive wheel (142) downwardly against the return portion (144) of the endless conveyer and in other particular ones of these types of embodiments the pump (18, 76, 160) is located outside the rope-like support member (32, 181, 164) so that the drive wheel (16, 68, 146) is urged upwardly against the conveying portion (28) of the endless conveyer.

Abstract: A device for turning the rotor of a gas turbine engine for purposes of inspection has a tubular rod projecting through the casing of the engine into proximity with rotor blades of the engine. The rod has a nozzle directing a jet of air onto the blades to turn the rotor. The rod is movable axially so that when it is desired to stop the rotor the free end of the rotor engages an annular surface of the rotor to exert a braking force thereon. The rod moves under the action of a spring. Air to the nozzle is supplied through a hand-operated valve and the air supply is taken through a cylinder having a piston connected to the rod. The arrangement is such that when the valve is opened to feed the nozzle and turn the rotor, the air pressure moved the piston in the sense of retracting the rod from the braking position.

Abstract: In a preferred embodiment, a drill gas turbine motor in which the housing structure directs pressurized gas both radially inwardly and axially along the longitudinal axis of the elongated housing, against vanes arranged along a circumscribing surface of the revolvable (rotatable) rotor mounted within rotor space within the housing to effect rotation of the rotor, and a drivable shaft extending from an opening at one end of the housing, and a dampening-spring mechanism at an opposite end of the housing and rotor arranged to dampen pressure and movement of the rotor in a direction away from the end of the drivable shaft thereby reducing wear on bearings supporting the rotar at opposite ends thereof, together with brake mechanism for manually exerting braking pressure against the rotor, and key mechanism for locking the rotor in a non-revolvable state during change of chuck on the drivable shaft, and the drivable shaft having formed in a distal end thereof a female receptacle receivable of a male end of a chuck.

Abstract: A clutch mechanism suitable for connecting a rotatable member to an output shaft of a motor, which mechanism comprises a body which is attachable to the output shaft and a resilient arm, one end of which is fixed to the body the other end of which is capable of engaging the rotatable member or part thereof, wherein the body is capable of gripping the output shaft in secure frictional contact to transfer rotational drive from the output shaft to the rotatable member only when the rotatable member is not restrained against rotation.

Abstract: An omnidirectional windmill employing lift type airfoils mounted about a vertical axis. The windmill includes a support frame which defines the vertically oriented axis about which the elongate airfoils rotate. Five vertically oriented stators are positioned outwardly of the airfoils about the windmill to form an omnidirectional diffuser. These stators extend radially from the vertical axis to substantially enhance the efficiency of the windmill. The stators also make the windmill self-starting. A friction heater is also disclosed in association with the windmill.

Abstract: A centrifugal compressor has at least one stage with its own impeller shaft, an inlet and an outlet for gas, and an epicyclic gear train for driving the impeller shaft. The epicyclic gear train comprises three members, a sun gear, a ring gear and a carrier on which a series of planet gears are mounted in mesh with the sun and ring gears. Means is provided for connecting a power input to one of the members of the epicyclic gear train, and means is provided connecting a second of the members to the impeller shaft. Means are provided for controlling the rotational speed of the third of the members to vary the speed of the impeller shaft of the compressor, and actuating means are provided for actuating the control means in response to the pressure of the compressed gas at the outlet.

Abstract: A fuel pump assembly for a gas turbine engine incorporates an impeller pump and a vane pump which are driven by a common drive shaft. A centrifugally operated clutch functions to disengage the vane pump from the drive shaft at a predetermined angular velocity. The vane pump is designed to fulfill dry lift, starting flow and pressure requirements for the engine. The impeller pump, alone, provides fuel to the engine near idle speed and above after the vane pump has been disengaged from the drive shaft.

Abstract: A pump assembly to be used for mining, and the like, is supported on rope-like members (32, 110, 112, 140, 181, 190) of an endless conveyer. In one type of embodiments a channel-shaped mounting member (20, 72, 138, 164, 192) of the pump assembly straddles the rope-like support members and allows the weight distribution of the pump assembly to cause a drive wheel (16, 68, 142, 146, 196) of the pump assembly to come into contact with the endless conveyer (28, 144, 198) to thereby drive a pump (18, 76, 134, 160, 182) of the pump assembly. In a particular one of these types of embodiments the pump (134) is mounted inside the rope-like support member (140) to urge the drive wheel (142) downwardly against the return portion (144) of the endless conveyer and in other particular ones of these types of embodiments the pump (18, 76, 160) is located outside the rope-like support member (32, 181 .[.164.].) so that the drive wheel (16, 68, 146) is urged upwardly against the conveying portion (28) of the endless conveyer.