Abstract: A self-insulating air delivery system maintains a desired air temperature of the conditioned air supplied thereinto for delivery to an aircraft. The system uses insulating airflow layers; a parallel layer and a counterflow layer. A starting section connects to a PCA unit and delivers conditioned air therefrom to an interior supply hose. The starting section also either creates bleed conditioned air or accepts conditioned insulating air and supplies it to an interior insulating hose that is annularly outward of the supply hose and in which air flows parallel to airflow in the supply hose. A reversing connector indirectly connects the supply hose to the aircraft and reverses the flow of air from the interior insulating hose to flow back toward the PCA unit in an exterior counterflow hose that is annularly outward of the interior insulating hose.

Abstract: Technologies are described for a recirculating evaporative air conditioning system. A pre-cooling evaporator may be coupled to a pre-cooling compressor and a pre-cooling condenser by a first closed refrigerant loop. A post-cooling evaporator may be coupled to a post-cooling compressor and a post-cooling condenser by a second closed refrigerant loop. A blower can draw ambient air through the pre-cooling evaporator and then blow the air out through the post-cooling evaporator. A discharge plenum can collect the air blown out through the post-cooling evaporator. A recirculation duct can recirculate a portion of the air collected at the discharge plenum back into the pre-cooling evaporator, into the post-cooling evaporator, or into any ducts or plenums associated therewith. A discharge duct can conduct a portion of the air collected at the discharge plenum into an aircraft, electrical equipment, an aircraft ground power unit, a passenger bridge, or other such aircraft ground support systems.

Abstract: A fluid coupling device for coupling torque between two members and utilizing a magnetorheological fluid having a controllable yield strength in shear in response to a magnetic field and having a determinable viscosity in the absence of a magnetic field and with the coupling device having a rotor, rotatably supported in a cavity in a housing with the cavity filled with the magnetorheological fluid and with the cavity and rotor having similarly shaped contours and constructed to concentrate the magnetic coupling effect through the fluid at the radially outer end of the rotor and a torque load simulator system utilizing the fluid coupling for determining the performance of a torque tool or other torque related apparatus relative to a predetermined standard of performance.

Abstract: Generally there is provided an improved design for a nutrunner appliance drive mechanism and strain gauge mounting. The design for the drive mechanism and strain gauge mounting of the nutrunner appliance facilitates placement of the strain gauge nearer the nut engagement extremity. The drive mechanism includes a shaft member mounted at an angle transverse to the motor shaft, and having a beveled gear at one extremity and a nut engaging member on the other extremity. A strain gauge is mounted between these extremities and provides signals to contacts rotating with the shaft. A brush contact protruding from a removable terminal block is used to pick up the electrical signals from the strain gauge contacts.

Abstract: A method of and apparatus for editing half-inch tape used for home recording of video material applies pulse-width modulation to prerecorded synchronizing pulses in predetermined time intervals. The interval is started with an eleven-bit header that is compatible with that of a commercially available system known as the VASS system. Time blocks are then encoded by pulse-width modulation with information identifying the particular recording session and the number of elapsed seconds minutes and hours since the beginning of the session. A check code completes the modulation during the interval for television systems such as PAL and SECAM that are adapted for fifty-Hz operation. For systems such as NTSC that operate at sixty Hertz, a ten-bit dummy code is added to complete the two-second interval. The code is entered without writing over the leading edge of the prerecorded synchronizing pulse, allowing the timing of those pulses to continue without interruption.

Abstract: An improved tensiometer for measuring the amount of tension in a wire or cable comprises a hand-held sensor unit having a handle, two spaced support arms supporting cable-engaging support nibs, an extensible sensor nib protruding from the handle, and a trigger grip operable to extend the sensor nib upwardly between the support nibs to deflect a portion of cable clamped therebetween. The support nibs are eccentric and rotatably adjustable between a plurality of settings to permit the sensor unit to accommodate a number of different cable diameters, and the throw ratios of the nibs are arranged to minimize their eccentricity and the resulting variation in length of the deflected portion of cable at different settings. The sensor unit measures the force required to deflect the cable with a load cell, the output of which is converted into and displayed as a tension value by a microprocessor display meter connected to the sensor unit.

Abstract: Generally there is provided a nutrunner appliance for automatically driving a nut having an electrical motor, gearing, and a strain gauge to monitor the applied torque. The control system employs analog comparator circuits acting on analog signals from the strain gauge to determine the torque being applied. During operation, the comparator detects a predetermined torque and shifts the motor to a lower velocity to lower the inertia of the system. When the strain gauge output corresponds to the desired final torque, a braking action is applied to the motor to quickly terminate the applied torque.

Abstract: A method and apparatus for measuring the torque generated by a slip-type fastening device (e.g. an air driven wrench) that generates multiple torque spikes. The method measures the torque by monitoring the torque output of the device as the torque increases. When the torque reaches a peak and drops, the measured torque value is displayed. No further torque outputs of the device are then displayed. The apparatus includes a first section which receives the torque output of the device and converts it into a torque signal. A second section displays the highest torque value received. The improvement is a third section which connects and disconnects the first and second sections based on the torque output of the device. When the torque output first increases, the first two sections are connected so that torque signals are passed from one to another. After a drop in the torque output, the two sections are disconnected and the highest torque value is displayed.

Abstract: A weigh scale apparatus in which forces caused by the applied load are transformed into moments of opposite sense and applied to opposite ends of a substantially rigid beam. Bending deflection of the beam is measured by centrally disposed strain gauge resistors to produce an electrical signal quantity proportional to the applied load. The conversion of applied load to moments of opposite sense is accomplished by a pair of spaced parallel pivot members which are suspended between the load receiving pan and the base such that the pivots tend to rotate in opposite directions. The beam is mechanically connected between the pivots such that it is subjected to the bending moment over substantially its entire length.

Abstract: The base of a weigh scale includes openings in the bottom thereof at each corner. The base is raised above a supporting surface by way of rigid foot members aligned with the openings in the corners of the base. Load cells in the form of deflection beams each having one of their ends fixed to the base while their other end contacts upper surfaces of their respective foot members. Damage to the load cells by side shock loads is eliminated by way of resilient coupling members connected between the foot members and the base.

Abstract: A low profile weigh scale includes a rectangular frame constructed on two opposite sides by U-shaped channel members. A plurality of removable platform members bridge central portions of the frame and are supported on their edges by angle irons on the sides of the channels. While the weigh scale has a relatively large weighing capacity, the frame and platform members can be easily disassembled and manually carried to different locations. In the preferred embodiment, load cells are mounted within the channel members at each corner. Removable covers are provided for the channel members to enable the user to gain easy access to the load cells for leveling purposes and the like.

Abstract: A microcomputer based system is designed to accurately detect the amount of previously applied torque to a fastener by way of a retorque test in which torque is subsequently applied to the fastener in the tightening direction until breakaway occurs. As torque is subsequently applied to the fastener a microprocessor operates to sample an analog torque input signal and convert it into discrete digital samples. These digital samples are stored in sequential memory locations during the tightening process. The microprocessor stops generating any further samples once a window containing the values of interest has been defined in memory. Then, the microprocessor examines the stored window samples in more detail to detect the sample value associated with the amount of torque previously applied to the fastener.

Abstract: The amount of previously applied torque to a fastener is measured by analyzing a series of digital torque values generated during a test of the fastener.

Abstract: Techniques are disclosed for supplying positive and negative voltages to electrical components in a system where power demand from the components needing voltage of one polarity is different from the power demand from components needing voltage of the other polarity. At least two batteries of substantially the same capacity are connected in series and used to supply the positive and negative voltages to the system components. In order to permit the batteries to be recharged simultaneously in series without damage to them the interconnection between the batteries and the loads are alternately reversed so that the batteries will discharge at substantially the same rate.

Abstract: Tension in a cable of a parking brake assembly is measured by way of a force measuring transducer device which is removably attachable to the lever arm bracket of the assembly located in the cabin of the automobile. The lever arm is lifted and the transducer device is positioned such that the arm presses against the load receiving surface of the transducer, such pressure being a function of the cable tension. Preferably, the transducer includes at least one flexure element connected to the load receiving surface operative to convert the force applied by the lever arm to electrical signals as a function thereof. The transducer device incorporates a retractable pin which engages an opening in the mounting bracket for the lever arm. The transducer is thus wedged between portions of the bracket and a pawl on the lever arm in a predetermined orientation such that the forces exerted by the pawl are applied generally perpendicularly to the flexure element.

Abstract: A weigh scale includes a flexure beam disposed between a platform and the base. Load transmitting devices operate to deflect the beam as a function of the load placed on the platform. Overload protection is provided for the beam to restrict the amount of beam deflection to maintain it within its elastic limits to thereby prevent yielding of the beam.

Abstract: Apparatus for sensing the force necessary to pull the lever arm of an automobile parking brake to a predetermined position. An elongated body includes a cavity for receiving the lever arm of the parking brake assembly. The body includes a switch arranged to come into contact with portions of the parking brake assembly when the lever arm is lifted to a predetermined position. A transducer is operative to measure the amount of force required to lift the lever arm to the position at which the switch contacts the parking brake assembly.

Abstract: A weigh scale includes a flexure beam disposed between a platform and the base. Load transmitting devices operate to deflect the beam as a function of the load placed on the platform. Overload protection is provided for the beam to restrict the amount of beam deflection to maintain it within its elastic limits to thereby prevent yielding of the beam.

Abstract: Apparatus for measuring the amount of previously applied torque to a fastener. A transducer is utilized to sense the amount of a subsequently applied torque to the fastener and provides an output signal representative of the applied torque. The torque is applied until further motion or breakaway of the fastener is obtained. Typically, the signal from the transducer increases until breakaway of the fastener is obtained and then the signal decreases momentarily to a valley before it again increases with further applied torque. In those instances where the particular fastener does not exhibit a well-defined valley torque signal, provision is made for detecting the value of the transducer torque signal upon breakaway. Preferably, circuitry is provided for artificially creating the valley when there is a change of slope in the torque signal above a given threshold level.