Abstract: A fish cage having a frame structure defining an enclosure with a top and a bottom and an intersecting side. The frame is adapted to rest on the bottom of an outdoor body of water and is covered with a first netting on the top and side but not the bottom. The first netting has mesh openings sized to permit ambient water and suspended particles therein to circulate through the cage but prevent predators and competitors for food of the fish under study from entering the cage. A second netting covers the bottom of the enclosure. The second netting has second mesh openings larger than the first mesh openings and sized to prevent the fish being studied from leaving the enclosure as well as permit plant and animal life at the bottom of the body of water to enter the enclosure, thereby providing a more natural environment for the fish under study. The enclosure includes a door to permit access to the interior of the enclosure.

Abstract: A hydraulically powered surgical device (20) includes a surgical instrument (24) having a tool (36) is mounted to one end of a handle (26). A hydraulic actuator (62) is mounted to the opposite end of the handle (26) and is also operatively connected to the tool (36). A source of hydraulic pressure includes a fluid reservoir (46) mounted with respect to an actuating element (21). The actuating element (21) is used to selectively apply a hydraulic pressure to the hydraulic actuator (62), thereby operating the tool (36).

Abstract: A surgical head clamp having a C-shaped frame with a fixed head engaging pin on one side and a pair of head engaging pins on the opposite side. The opposite side of the clamp also has a rotation mechanism for adjusting the angular position of the pair of head engaging pins and a translation mechanism for linearly moving the pair of head engaging pins with respect to the fixed head engaging pin.

Abstract: An injection molding machine utilizing brushless DC motors in its servomechanism drive systems. Brushless DC motors provide a cost effective high power drive system which has the simplicity of control of brush-type DC motors. By utilizing higher resolution encoders and controlling pressure with the servomotor velocity control loop, motor cogging and zero velocity oscillatiions are minimized.

Abstract: The identity of a desired video disk is compared to the identity of a video disk in use in a video disk player. If the desired video disk is not the same as the video disk in the player, instructions are given to change the video disk, and a comparison is again made.

Abstract: Use is made of crystalline alkali metal aluminum silicates of the zeolite type, having the formula (A.sub.2 O).sub.x.sup..multidot. Al.sub.2 O.sub.3.sup..multidot. (SiO.sub.2).sub.y wherein A=alkali metal, x has a value of 0.7-1.5 and y has a value of 0.8-4 and having a particle size between 0.1 and 100 .mu.m in an aqueous metal working fluid composition.

Abstract: A reheat blow molding machine has an improved article handling system that carries heated preforms by a carriage assembly from an oven to a roller chain conveyor which moves them to a blow mold from when the blown product is moved to an eject station. The motions are linear and cyclical or periodic, drive means for such intermittent motions being provided. Preforms are handled in groups of four, each one being supported by its capping ring in a locating notch on the carriage and by the finish groove in a holder notch above it when it is transferred to the conveyor. All notches are open on the side facing the oven and have self-centering features to get and keep alignment for transfer and positioning at the blow mold. The carriage which moves preforms horizontally toward the conveyor and raises them to the elevation for transfer to the holder notches of the conveyor.

Abstract: A reheat blow molding machine has an improved article handling system that carries heated preforms by a carriage assembly from an oven to a roller chain conveyor which moves them to a blow mold from when the blown product is moved to an eject station. The motions are linear and cyclical or periodic, drive means for such intermittent motions being provided. Preforms are handled in groups of four, each one being supported by its capping ring in a locating notch on the carriage and by the finish groove in a holder notch above it when it is transferred to the conveyor. All notches are open on the side facing the oven and have self-centering features to get and keep alignment for transfer and positioning at the blow mold. The carriage which moves preforms horizontally toward the conveyor and raises them to the elevation for transfer to the holder notches of the conveyor.

Abstract: A reheat blow molding machine has an improved article handling system that carries heated preforms by a carriage assembly from an oven to a roller chain conveyor which moves them to a blow mold from when the blown product is moved to an eject station. The motions are linear and cyclical or periodic, drive means for such intermittent motions being provided. Preforms are handled in groups of four, each one being supported by its capping ring in a locating notch on the carriage and by the finish groove in a holder notch above it when it is transferred to the conveyor. All notches are open on the side facing the oven and have self-centering features to get and keep alignment for transfer and positioning at the blow mold. The carriage which moves preforms horizontally toward the conveyor and raises them to the elevation for transfer to the holder notches of the conveyor.

Abstract: A reheat blow molding machine having an article handling system that carries heated preforms by a carriage assembly from an oven to a chain conveyor which moves them to a blow mold from whence the blown product is moved to an eject station. Attached to the chain conveyor are preform holder assemblies each of which contains a resilient spindle nose which supports the preforms by engaging an internal surface at one end of the preform.

Abstract: A method is disclosed for detecting the presence of a workpiece characteristic and controlling the sequence of execution of operational steps in a machining program. First instructions in a machining program cause a sensing element to execute a scanning cycle to detect workpiece characteristics. Second instructions in the machining program test for the presence of the workpiece characteristics to determine the next operational step to be executed. The next operational step may be sequentially located in the program or may be identified by third instructions which define a nonsequential program location. Jump instructions are also provided to execute an unconditional jump to operational steps defined by a jump location instruction in the program.

Abstract: A method and apparatus are disclosed for controlling a machine tool as a function of the torque load on a cutting tool. The apparatus detects the spindle motor current which may vary over four decades, the spindle motor voltage which may vary over two decades and the cutting tool angular velocity which may vary over three decades. The decimal values of the detected variables are converted to corresponding logarithmic values and stored in digital form. A microprocessor utilizes the stored values to calculate the value of torque on the cutting tool which may vary over five decades. A microprocessor determines the idle torque by averaging the torque which is measured several times over one spindle revolution. The idle torque is subtracted from subsequent gross torque measurements to provide an indication of actual cutting load on the tool. The operation of the machine is modified in response to the actual torque exceeding a predetermined reference torque value.

Abstract: The invention relates to a computer operated robot arm in which the operation of the robot arm is controlled by a first program defining absolute coordinate values of points necessary for a basic cycle of operation and at least one second program defining absolute coordinate values of points necessary for a conditional cycle of operation. After being initially defined a single time during a teaching mode of operation, the invention allows the second program to be recalled many times during the execution of the first program by merely utilizing an address code. Consequently, even though the second program is defined by absolute coordinate data, the second program may be used to control the robot arm at any spatial location.

Abstract: A method and apparatus are disclosed for using a numerically controlled turning machine to automatically cut a thread in response to programmed data defining certain thread cutting parameters. The programmed data defines an initial thread cutting pass and the final thread depth. The method and apparatus cause the cutting tool to make a number of iterative thread cutting passes relative to the rotating workpiece with successive passes being made at correspondingly smaller cutting depths. The threading cycle is terminated by two finish passes at a predetermined minimum depth of cut.

Abstract: The present invention is a DC motor drive circuit in which each end of a center tapped supply transformer is connected through a pair of back-to-back thyristors to corresponding ends of a center tapped choke coil. The motor armature is connected between the two center taps. After each zero crossing of an AC input signal, a ramp signal is generated. The ramp is comprised of two linear segments of different slopes to improve the linearity of the output of the thyristors as the conduction angle approaches the zero crossing point. Comparator circuits are responsive to the ramp signal and a command signal for generating trigger pulses to the thyristors. The comparators are biased so that with no command signal present, the comparators operate the thyristors to produce a small alternating loop current through the transformer and the choke with each half cycle of the AC input signal. This maintains conduction through all the thyristors without dithering the motor armature.

Abstract: On a machine having a cutting tool moving relative to a rotating workpiece, a method and apparatus are disclosed for holding a constant relationship between the cutting tool and an angular position of the workpiece for different velocities of the cutting tool which produce correspondingly different following errors. The invention is applicable to a numerically controlled turning machine of the type maintaining a constant initial contact point between the cutting tool and an angular position of a rotating workpiece in response to a constant following error during successive machining passes. A first machining pass is executed in response to a first velocity signal which causes the cutting tool to initially contact the rotating workpiece at a first angular position thereof. Before the execution of a subsequent machining pass, the velocity signals associated with the first and subsequent machining passes are used to calculate the difference in following errors between machining passes.

Abstract: A machine control system including a programmable machine function controller comprised of a logic processor and a data processor. The logic processor is responsive to first devices on a machine, e.g. limit switches and push buttons, for controlling second devices on the machine, e.g. motor starters and solenoids, in accordance with a program representing a desired machine operation. The data processor operates asynchronously with the logic processor but responds thereto for selecting programs of arithmetic instructions relating to the machine operation. The system includes a panel of push buttons, lights and read-outs located remotely from the controller. Signals are transmitted between the controller and the panel using asynchronously operating receiver/transmitters which multiplex and transfer the signals on a serial basis. The machine includes at least one movable member in mechanical communication with a driving mechanism.

Abstract: An apparatus is provided for moving a machine element along a straight line path in a plane defined by two orthogonal axes of motion. A switching device is provided for producing an input signal representing the slope of the straight line path which is defined by the tangent of the angle formed between the path and a first axis of motion. In accordance with mechanisms known in the prior art, first output pulses are generated for moving the machine element along the first axis of motion at an arbitrary velocity. The invention provides a counter circuit having a modulus as a function of the component of slope along the first axis of motion. Further in response to the input signal and each of the first output pulses, the counter circuit increments a number of times represented by the component of slope along the second axis of motion.

Abstract: A multiprocessor system is disclosed for controlling a cycle of operation of a machine. The cycle of operation of the machine is governed by a first set of devices and is monitored by a second set of devices. The multiprocessor system includes a logic processor unit containing a first program of logic instructions defining the cycle of operation of the machine. A bus and associated circuits are connected between the logic processor and the devices on the machine. The logic processor is responsive to the second set of devices and makes logic decisions in a continuous and cyclic manner to control the operation of the first devices thereby causing the cycle of operation of the machine to conform with the first program. The multiprocessor system further includes one or more independent data processors which are connected to the bus and operate asynchronously with the logic processor. The data processors respond to output signals from the logic processor which select preprogrammed sets of arithmetic instructions.

Abstract: A method and apparatus are disclosed for modifying command signals representing predetermined positions of a machine element relative a workpiece as a function of measurable unprogrammed changes in the relative position therebetween. The machine element is responsive to a servomechanism circuit which in turn responds to a control device producing the command signals to command motion of the machine element to programmed points relative to the workpiece. The servomechanism circuit produces interrupt signals for transferring the command signals thereto. A measuring circuit is responsive to the unprogrammed change in relative position between the machine element and the workpiece and is operative to produce feedback signals representing the direction and magnitude of the change in relative position. A first circuit is responsive to the measuring circuit for producing a first signal representing a current unprogrammed change in relative position with reference to a predetermined point.