Abstract: An arrangement at rotating shafts with a wheel fixedly mounted to the shaft, which wheel rotates in a housing surrounding the wheel, an essentially pipe-shaped element surrounding the shaft, an with essentially axially sealing surface provided sealing device between the pipe-shaped element and the wheel and a passage in the housing for the shaft with a sealing device, which seals against the pipe-shaped element. There is mounted a fastening device on the shaft for axial displacement of the pipe-shaped element in order to cause a sealing effect by means of the sealing device between the pipe-shaped element and the wheel. The fastening device is fixed in sealing position by a locking device.

Abstract: A self-flushing, magnetic separator technique including feeding the medium to be separated to one end of a matrix in a container; collecting separated fluid from the other end of the matrix; accumulating at least one matrix volume of the separated fluid in a chamber in the container adjacent one of the ends of the matrix stopping flow to and from the matrix, trapping the accumulated fluid in the chamber; and in one embodiment introducing a pressurized drive fluid to the chamber and venting the other end of the matrix to urge the accumulated fluid to move through and flush the matrix.

Abstract: Apparatus for uniformly grinding the peripheral surface of a kiln ring of a rotating rotary kiln to axial flatness includes a grinder; an electrical motor for continually driving the grinder; a pneumatic cylinder for urging the grinder against the surface of the kiln ring; a current transformer for sensing the magnitude of current flow to the motor; and a controller which compares the magnitude of sensed motor current to a set point reference of desired current flow to the motor and supplies pressurized fluid to the pneumatic cylinder at a pressure which varies as an inverse function of the difference between sensed current and set point references and maintains the current flow to the motor equal to the set point reference.

Abstract: Apparatus for detecting a load within a preselected bin of an automatic storage rack has a transducer for directing an ultrasonic beam into the bin and for detecting an echo reflected from a load struck by the beam; a digital counter adapted to generate plural bit binary pulses which is started upon initial transmission of the ultrasonic beam; and a programmable memory coupled to the counter and programmed to generate a given bin-ful output signal upon initial transmission of the beam and to subsequently generate the opposite binary bin-empty output signal if no echo has been detected when the pulses from the counter stored in the memory indicate that sufficient time has elapsed after initial transmission for the beam to travel a predetermined distance into the bin and for an echo from a load struck by the beam to return to the transducer.

Abstract: An oil shale retorting method and apparatus moves a bed of oil bearing shale particles along a generally horizontal path and passes through the bed at spaced points a plurality of discrete nonoxidizing gas streams heated to different oil educting temperatures to vaporize and educe different weight fractions of oil from the kerogen in the shale into the gas streams. Preferably the heated gas streams are also passed through the moving shale bed upstream from distillation of the volatile oil constituents to preheat the shale particles and condense the educted oils which become suspended as stable mists and are mechanically separated from the gas streams. Heat energy is preferably removed from the spent shale particles of the moving bed by burning them with combustion air downstream from the retorting sites, and such heat energy is transferred to the nonoxidizing streams to raise them to different oil educting temperatures before they are passed through the moving bed to educe oil from the shale particles.

Abstract: A ground speed control for an agricultural combine driven by a turbocharged engine through a variable transmission continuously monitors a plurality of speed and load parameters of the combine and engine, identifies the controlling parameter representing the limiting capacity in the harvesting process as field conditions change, and varies combine ground speed in response to such controlling parameter to maximize the harvest cutting rate. Sensors monitor ground speed, boost pressure and engine speed parameters and convert them to electrical signals which are compared to boost pressure and ground speed setpoint signals selected by the operator and to a fixed engine speed setpoint signal to derive error signals for such parameters. Voltage level sensitive OR-means and AND-means establish deadbands for the error signals having upper and lower limits on opposite sides of the corresponding setpoint signals.

Abstract: In accordance with the centrifugal erosion testing method of the invention, a material specimen is rotated with a flat surface facing the direction of rotation and a narrow stream of an abrasive particle slurry is concurrently flowed at a preselected rate in a radial direction across the flat surface, the rotating step being at sufficiently high angular velocity to urge the abrasive particles by Coriolis acceleration into a compacted mass against the flat surface and erode material therefrom by scouring type action as the particles flow radially outward. The rotating and flowing steps are continued for a sufficient preselected duration to erode material to a measurable depth, and the depth to which the flat surface is worn by the abrasive particles is measured as an indication of the erosion resistance of the specimen material.

Abstract: A combine harvester vehicle having threshing, separating and cleaning stages for cut crop material and a tailings return elevator for conveying tailings to one of the stages for recycling, is provided with a tailings monitor including a photodiode for transmitting a radiant energy beam across the path of tailings being conveyed in the elevator, an electrical circuit including a photodetector for deriving digital signals indicative of whether the beam is impinging on the photodetector or is being interrupted by the tailings, and an RC circuit which charges a capacitor through a resistance when the digital signal is present indicating that the beam is interrupted and discharges it when the opposite digital signal is present to thereby develop an average voltage across the capacitor which is an analog of the percentage of time that the beam is interrupted by the tailings being conveyed in the elevator and can be visually displayed on a voltmeter to the combine operator as a measure of tailings volume.

Abstract: Apparatus for destroying weeds in and around crop rows has a high voltage source of electricity mounted on a vehicle; a coulter wheel for connecting the high voltage source to the ground; a plurality of weed contacting electrodes carried on the vehicle and insulated therefrom; and a plurality of isolating electrical reactance inductors each of which connects a weed contacting electrode to the high voltage source and limits the magnitude of current flowing through the high voltage source when the electrode contacts a weed to thereby minimize the voltage drop across the high voltage source and maintain substantially constant voltage on the remaining electrodes.

Abstract: A self-flushing, magnetic separator technique including feeding the medium to be separated to one end of a matrix in a container; collecting separated fluid from the other end of the matrix; accumulating at least one matrix volume of the separated fluid in a chamber in the container adjacent one of the ends of the matrix; stopping flow to and from the matrix, trapping the accumulated fluid in the chamber; and in one embodiment introducing a pressurized drive fluid to the chamber and venting the other end of the matrix to urge the accumulated fluid to move through and flush the matrix.

Abstract: A method and apparatus for recovering oil from shale comprises forming a bed of oil bearing shale particles on a plurality of rotatable apertured cylindrical rollers having filler members in the nip between adjacent rollers; transporting the bed by rotating the rollers to frictionally engage the shale particles and transfer them onto and across the filler members to continuously agitate the particles as they are being transported at a velocity substantially lower than the circumferential velocity of the rollers; passing through the moving bed at spaced points a plurality of discrete streams of nonoxidizing gas heated to different temperatures sufficiently high to educe different weight fractions of oil from the kerogen in the shale as vapors into the gas streams; and separating the different weight oil fractions from the gas streams.

Abstract: An oil shale retorting method and apparatus moves a bed of oil bearing shale particles along a generally horizontal path and passes through the bed at spaced points a plurality of discrete nonoxidizing gas streams heated to different oil educting temperatures to vaporize and educe different weight fractions of oil from the kerogen in the shale into the gas streams. Preferably the heated gas streams are also passed through the moving shale bed upstream from distillation of the volatile oil constituents to preheat the shale particles and condense the educted oils which become suspended as stable mists and are mechanically separated from the gas streams. Heat energy is preferably removed from the spent shale particles of the moving bed by burning them with combustion air downstream from the retorting sites, and such heat energy is transferred to the nonoxidizing streams to raise them to different oil educting temperatures before they are passed through the moving bed to educe oil from the shale particles.

Abstract: A fork lift truck has a safety system for inhibiting further raising of the carriage or further forward tilting of the mast when an excessive tilting moment is acting on the truck and permits the truck operator to selectively simulate an overload on the truck and provides a visual indication that the safety system has responded properly to such simulated overload, thereby permitting the truck operator to test whether or not the truck is protected from picking up an overload.

Abstract: A conduction limit protective arrangement for a power transistor switch regulated by a train of control pulses is disclosed which automatically changes the conduction limit as a function of the voltage, current, and temperature conditions to which the switch is subjected so that it is within its safe operating area limits at all times, thereby permitting the switch to carry maximum current while being fully protected at all times.

Abstract: A calcining combustor for the suspension preheater of a rotary kiln cement manufacturing plant having a cooler for the clinker comprises an upright furnace vessel having an outwardly spiraling gas exhaust duct at its upper end leading to a preheater gas/meal separator and a mixing portion at its lower end; an inlet for hot combustion air from the cooler into the mixing portion; an inlet for cement meal from the preheater into the mixing portion downstream from the combustion air inlet to entrain the meal in the rising combustion air; and burners for injecting fuel into the air/meal stream downstream from the meal inlet to calcine the meal by heat released by burning of the fuel with the combustion air.

Abstract: A power transistor switch is protected against thermal destruction that might be caused by accidental short circuiting of the load being switched by a protective circuit having a base-drive-removing transistor in shunt to the base-emitter junction of the power transistor; an RC circuit including a capacitor in series with a resistor connected across the power transistor with the capacitor coupled across the base-emitter junction of the base-drive-removing transistor; a forward-biased shunting transistor connected across the capacitor; a shunt-removing transistor connected across the base-emitter junction of the shunting transistor; and a turn-on transistor triggerable to the conductive state by a turn-on signal for applying base drive to the power transistor and for forward biasing the shunt removing transistor to thereby turn off the shunting transistor and permit the capacitor to charge.

Abstract: A weed destroying system carried on a vehicle and having electrodes for contacting weeds and a high voltage generator and a step-up transformer for supplying high voltage to the electrodes is provided with a tamper-proof safety system having redundant safety interlocks to effectively ground the vehicle and redundant safety interlocks to prevent energization of the generator until the vehicle is traveling at a predetermined speed and which de-energizes the generator if any one safety interlock is bypassed or fails in an unsafe condition, thereby requiring plural simultaneous failures to create a condition that is hazardous to the operator or to a bystander. The safety system also provides immediately-visible warning of the electrical hazard created by the apparatus and provides visual and aural indications to the operator when a safety interlock has been bypassed or is jammed closed.

Abstract: Weed destroying apparatus carried on a vehicle has a generator; a step-up transformer having its secondary winding coupled to electrodes for contacting and killing weeds; a programmable semiconductor logic array; a first contactor coupled to an output of the logic array for connecting the generator to the transformer primary winding in the weed killing mode; a second contactor coupled to an output of the logic array for connecting the generator to electrical outlets for supplying electrical power to auxiliary farm equipment in a standby mode; a run/standby switch for providing binary signals to the logic array indicative as to whether the apparatus is to operate in the weed killing mode or the standby mode; a plurality of safety systems each of which has redundant interlock means for preventing an unsafe condition in which high voltage would be a hazard in the weed killing mode and sensing means for providing binary signals to the logic array indicative of whether each interlock means is in the safe condition

Abstract: Roller grate method and apparatus for simultaneously transporting, agitating and exchanging heat with a bed of solid mineral particles has elongated cylindrical horizontal rollers with gas passage apertures therethrough, a hopper for feeding mineral particles onto the rollers and forming a bed having a depth several times greater than the average diameter of the particles; a drive source to rotate the rollers and frictionally engage the cylindrical surfaces with the particles in the lowermost layer of the bed and urge the bed along a path of travel transverse to the axes of the rollers; elongated filler members disposed in the nip between adjacent rollers to prevent the particles from jamming the rollers and to provide resistance to the flow of the bed along said path of travel; and a heat chamber spanning the rollers and a fan for forcing a heat transfer gas stream through the gas passage apertures in the rollers and through the bed as it is being transported, the rollers and the filler members being adapted

Abstract: A multi-stage cement calcining plant suspension preheater has a calcining combustor flow connected with a cyclone separator in the uppermost stage and helical duct inertial separators in the remaining stages which are lower in height and in pressure drop than conventional cyclone separators and permit reduction in height of the preheater tower and use of a lower horsepower fan to move kiln-off gases through the preheater.