Abstract: An automatic level device for sensing the height and pitch of an aircraft and for adjusting a loader platform to align with the aircraft. An umbilical cord connected between the platform and the aircraft includes a tube partially filled with mercury and having a plurality of electrodes spaced along one end of the tube. As the height of the aircraft changes the mercury contacts a different number of electrodes and the electrodes provide signals for adjusting the level of the platform and aligning the platform with the aircraft.

Abstract: Apparatus for mounting on a crane or other construction equipment for detecting the presence of an electrical power line. A reference pickup coil mounted on an upper machinery works or other portion of the equipment generates a reference signal proportional to the strength of a magnetic field in a work area. Other pickup coils mounted on a crane boom or other portions of the equipment which may extend into closer proximity to power lines develop signals which are compared with the reference signal. When any of these signals exceed the reference signal by a predetermined amount a warning signal is developed. Coils having the proper ratio of core length to diameter and having coil winding which extend along approximately half the core length provide output signals which have a predictable amplitude.

Abstract: Apparatus for removably connecting a strain cell to a polished rod of a well pumping unit and for preventing the development of strain cell output signals due to bending of the polished rod. The strain cell is connected to a frame member which can be clamped to the polished rod where strain cell output signals are obtained due to a change in tensile load on the rod. A pair of hinges, between the frame member and the polished rod, minimizes the development of strain cell output signals due to bending of the polished rod. The frame member can be adapted to mount on a variety of sizes of polished rods. The apparatus can be removed or replaced without the use of special skills or special equipment.

Abstract: A lightweight pup joint comprising a length of pipe with male and female union subs on the ends and having integral metallic fluid contacting components. The pipe is formed with a minimum wall thickness required for the intended pressure rating and includes a radially enlarged portion on one end to form a male sub. The other end of the pipe includes a small radial flange sized so a union nut can be moved over the flange. A split female sub is assembled over the flange and held together by a snap ring. An annular sealing member seals gaps between portions of the female sub, seals an interface between the flange and the female sub, and seals a gap between the flange and a male sub of an adjacent pipe. At least one ear on the pipe fits into a slot in the female sub to prevent rotation of the female sub when the union nut is threaded onto the female sub.

Abstract: Apparatus for detecting fluid pound in a sucker-rod oil well, using values of sucker-rod position and of sucker-rod load to calculate a reference position and a selected load value. The apparatus continually updates the reference positions and selected load values to compensate for drift in characteristics of transducers used in determining rod load and rod position and for a gradual change in well characteristics. When the sucker-rod moves downward to the updated reference position, the actual rod load is checked against the updated selected value and a warning signal develops when the amount of load exceeds the updated selected value.

Abstract: An actuator for converting axial movement into incremental rotation. Axial movement of a plunger provides successive increments of rotary motion of a shaft in a first direction through a predetermined angle, then automatically provides successive increments of rotation of the shaft in a reverse direction. After moving through a predetermined angle in the reverse direction the shaft rotation is again automatically reversed so the shaft rotates in the first direction.

Abstract: A synchronized subharmonic controller for a dual coil electromagnetic vibrator, which derives both power and timing from a single phase AC line, having a trigger circuit which operates the coils at one-third the power line frequency. A timing circuit is optically coupled to alternately fire a pair of oppositely-directed SCR's with each SCR connecting one of the coils across the AC line. The optical coupling reduces feedback from the coil circuitry to the timing circuit. A pair of capacitors supply additional power to operate the coils and to reduce the peak values of current supplied by the power line.

Abstract: A hydraulic circuit for selectively extending and retracting a mobile telescoping boom assembly and for independently extending and retracting an articulated pipe service line mounted on the boom assembly. The circuit can be used with a hydraulic ram to extend and retract the boom assembly or a winch and cable arrangement can be used. A pair of winches are used to extend and retract the articulated service line.

Abstract: Method and apparatus for checking a sucker-rod pumped well for defects by weighing the well. A load cell connected between the sucker-rod and a power unit develops a signal representative of the load on the sucker-rod. The sucker-rod load is checked with the rod and an associated downhole pump plunger in a stationary position. The load readings are corrected for load cell drift by a computer, and a corrected load value displayed on a digital display unit. The load readings are updated periodically and any changes in load reading can be used to determine the presence of a defect and to ascertain the type of defect in the pumping apparatus.

Abstract: Method and apparatus for detecting problems in sucker-rod well pumps and for determining which type of problem occurs. A first transducer provides a signal representative of the load on a sucker-rod string and a second transducer provides a signal representative of the sucker-rod position. The load signal and the position signal are used to generate a dynagraph of rod load vs. rod position with the pump working normally. A working dynagraph is continually compared with the normal dynagraph and a working load signal is continually compared with a normal rod load signal to detect problems in the pumping system and to determine the type of problem detected if one does develop.

Abstract: Apparatus for measuring the distance between an electric welding torch and a workpiece especially useful with an aluminum workpiece. A nonconsumable electrode is mounted adjacent the consumable electrode of the welding torch with the nonconsumable electrode electrically isolated from the consumable electrode. A power supply connected to the consumable electrode provides an auxiliary arc and develops a consumable electrode voltage proportional to the distance between the torch and the workpiece. The consumable electrode voltage can be used to develop signals which guide the torch along a groove in the workpiece.

Abstract: A chordal action isolation wheel assembly for reduction of noise in track-laying vehicles by using a pendulous isolation wheel to isolate chordal track forces from a smaller drive sprocket. The drive sprocket is mounted on a drive shaft and one end of a pendulous arm is rotatably connected to the drive shaft. The isolation wheel is rotatably mounted on the other end of the pendulous arm and an endless track is trained about both the isolation wheel and the drive sprocket with only a small portion of the periphery of the drive sprocket contacting the endless track. The larger diameter of the isolation wheel causes a gentle lowering of the endless track onto the drive sprocket to reduce the force transmitted to the sprocket wheel and reduced noise. Chordal impacts of the track shoes occur against the isolation wheel, and the resulting vibrational energy is absorbed by the pendulous action of the isolation wheel assembly.

Abstract: A telescoping boom assembly supported articulated well service pipeline for the transfer of pressurized fluids from service vehicles to petroleum wellheads for the treatment and stimulation of production oil wells. The boom assembly is mounted on a truck, trailer, or other suitable mobile transport, and the articulated pipeline comprises a plurality of long straight pipeline sections interconnected by a plurality of shorter pipe sections and by swivel joints. The inboard end of the pipeline is connected to a supply line by an inboard pipe and a pair of swivel joints. The pipeline can be folded into a cluster and tilted for storage adjacent the inboard end of the boom assembly and the clustered pipeline moved away from the service vehicle before unfolding the pipeline from the cluster.

Abstract: A rotary irrigation system comprises a continuous length of irrigation pipe having sprinkler heads spaced along the length thereof with an inboard end of the irrigation pipe connected to a fixed upstanding water supply pipe and with an outboard end of the irrigation pipe connected to power apparatus for rotating the outboard end of the pipe about the axis of the irrigation pipe. The inboard end of the irrigation pipe is connected so it cannot rotate about the axis of the irrigation pipe, but can move about the water supply pipe. The irrigation pipe is supported at uniformly spaced intervals along its length by a plurality of wheels with the wheels having hubs which receive the irrigation pipe and allow the wheels to rotate in one direction only. The power apparatus applies a torque to rotate the outboard end of the irrigation pipe in a first direction to wind up the pipe.

Abstract: A fire-safe seal for use in a swivel joint in a pressurized fluid system subject to fire risk, the seal having both a metal anti-extrusion ring and an annular resilient non-metallic seal member to provide essentially zero fluid linkage at normal operating temperatures, and the anti-extrusion ring to provide an extremely low rate of leakage in the event high temperature should destroy the resilient seal member. A curved spring or other metal anti-cocking device biases the anti-extrusion ring tightly against the junction of a male and a female joint to ensure that the ring remains in position after the resilient seal member is destroyed to prevent leakage through the junction.

Abstract: A driving and braking system having solid state switches for use with an electric motor. A first switch in series with a motor armature carries current from a power supply to the motor during the driving operation. A second switch couples a voltage from the motor armature to the first switch to render the first switch nonconductive and place the motor in a braking mode in response to a braking signal. The first switch provides armature current and couples a voltage from the motor armature to the second switch to render the second switch nonconductive and place the motor in a driving mode in response to a driving signal. The motor can be switched between the braking mode and the driving mode without bringing the motor to a stop.

Abstract: Methods and apparatus for detecting fluid pound in a sucker-rod oil well, using maximum and minimum values of sucker-rod position and of sucker-rod load to calculate a reference position and a selected load value. The apparatus automatically calculates the reference position and the selected load value according to the characteristics of the well and of the well pumping equipment. When the sucker-rod moves downward to the reference position, the actual load value is checked against the selected value and in one embodiment of the invention a warning signal develops when the amount of the load exceeds the previously selected load quantity. In another embodiment a warning signal develops when the rate of change of the load is at a maximum below the reference position. In a third embodiment a warning signal develops when a minimum rate of change of the load occurs below the reference position.

Abstract: A rotary irrigation system comprises a continuous length of irrigation pipe having sprinkler heads spaced along the length thereof with an inboard end of the irrigation pipe connected to a fixed upstanding water supply pipe and with an outboard end of the irrigation pipe connected to power apparatus for rotating the outboard end of the pipe about the axis of the irrigation pipe. The inboard end of the irrigation pipe is connected so it cannot rotate about the axis of the irrigation pipe, but can move about the water supply pipe. The irrigation pipe is supported at uniformly spaced intervals along its length by a plurality of wheels with the wheels having hubs which receive the irrigation pipe and allow the wheels to rotate in one direction only. The power apparatus applies a torque to rotate the outboard end of the irrigation pipe in a first direction to wind up the pipe.