Abstract: A phase-control type of closed-loop control system for motors. A reference signal generator generates a digital reference signal having a binary value which varies between first and second values n times during each a-c input voltage cycle. An error signal generator generates a digital error signal having a binary value which varies in accordance with the difference between the desired and actual values of a motor variable such as armature current. The most significant bits of the digital error signal are utilized to select the angular range within which firing signals will be applied to a phase-controlled rectifier network that is arranged to drive the motor. The least significant bits of the digital error signal are compared with the digital reference signal to determine the time, within the selected angular range, when firing signals will be applied to the controlled rectifier network.

Abstract: A cooling system for gear reducers having a housing with a lubricant therein, in which a motor for the pump and heat exchanger are mounted on a base structure to form a unitary assembly which can be fully assembled in the manufacturing plant and delivered to and installed at the site of the gear reducer. The temperature of the lubricant in the line from the gear reducer to the pump is sensed by a temperature responsive device and a control valve in the coolant line is regulated thereby for producing an intermittent flow to control the efficiency of the heat exchanger and thereby regulate the temperature of the lubricant in a predetermined range. A second temperature responsive device may be utilized to sense the temperature of the lubricant in the hot lubricant line and to shut down the equipment in the event the temperature of the lubricant, and consequently the temperature of the gear reducer, exceeds a predetermined value.

Abstract: A motorized conveyor pulley in which a rim and two end discs form a closed compartment and an electric motor and speed reducer are disposed in axial alignment with one another in the compartment. The motor is supported by a nonrotatable shaft extending through one end disc, and the speed reducer is connected to the motor by an input shaft and has an output shaft which is rigidly connected to the other end disc for rotating the pulley in response to the operation of the motor. A bearing is provided on said first shaft for permitting free rotation of the pulley with respect to the motor and the shaft, which are preferably prevented from rotating by a torque arm connected to the shaft. The air in the compartment is recirculated through the motor and along the inside surface of the pulley rim to cool the motor.

Abstract: A lubricated bearing assembly with rollable elements such as balls is disclosed. The rollable elements may be in a bearing cage and disposed between inner and outer races as in typical ball bearing unit. The inner race is secured to a rotatable shaft and the outer race is mounted in a frame of a machine. A first grease cavity is provided on one axial side of the rollable elements and a second grease cavity is provided on the opposite axial side of the rollable elements. The grease is introduced into one of the cavities, for example, the first cavity and is directed in an axial direction toward the rollable elements and to the spaces between such rollable elements to make sure that grease is provided in such spaces. The opposite grease cavity, for example, the second grease cavity, is provided with walls forming vanes in a radial direction.

Abstract: A digital firing control for a three-phase full wave silicon controlled rectifier converter. An error signal, in digital form, representing a desired change in firing angle which is a function of the difference between the current being supplied by the converter and a desired current, is utilized to advance or retard the firing angle of the SCR's as required to eliminate the error. Each subsequent firing command is referenced on a time basis from the firing command of the previously fired SCR in the firing sequence rather than being referenced from the zero voltage point of the alternating current supply voltage. The error signal is averaged over the time interval between firing commands so that the control responds to the average difference between the current being supplied and the desired current.

Abstract: A multiple power path concentric speed reducer in which a center shaft having a pinion thereon and an axle having an externally toothed gear thereon are disposed coaxially with respect to one another, and a plurality of gear trains operatively connect the pinion with the gear to provide multiple power path between the pinion and gear. The power or load is distributed equally between the several gear trains, and the center shaft may be the power input member, a housing the power output member and the axle the reaction member; or the center shaft may be the power input member, the axle the power output member, and the housing the reaction member. The concentric speed reducer is particularly adapted for use in vehicle wheel drives, especially in off-the-highway heavy duty equipment, wherein the speed reducer for each wheel is driven by a separate motor, such as a DC motor, mounted in or on the axle of the respective wheel.

Abstract: A drive mechanism for a belt conveyor system having a driven pulley and a belt trained thereon, the mechanism including a speed reducer disposed in the pulley and having coaxial input and output shafts, the output shaft being a reaction shaft for the rotatable housing of the speed reducer. The housing of the speed reducer is in axial alignment with the pulley and is connected thereto for driving the pulley. A brake is provided for restraining the rotation of the output shaft, and may consist of a disc rotatable with the output shaft and a hydraulically operated head controlled by a system including a pump driven by the output shaft in response to the load on the belt of the conveyor. The drive for the pump senses the load on the conveyor belt by the reaction response of the output shaft, thereby varying the rate at which the pressure in the hydraulic system increases to control the friction head indirectly in response to the conveyor load.

Abstract: An adjustable valve assembly as disclosed wherein a plurality of valve blocks may be stacked or ganged side by side, and each used to control a machine part. Each valve block has a solenoid actuated valve to control flow of fluid such as air into a piston and cylinder assembly to move a part of the machine. The air flow is adjustably throttled by a needle valve in either the forward stroke or return stroke of the machine part. The needle valve has a normal at-rest position and may be moved in two directions toward opening and toward closing to establish a variable orifice in the valve block. First and second line shafts extend transversely to all of the various valve blocks for actuating the needle valves in the several valve blocks. Such actuation includes for each valve block first and second drive trains from the line shafts to the needle valve member with first and second clutches in the first and second drive trains and selectively actuable for opening and closing movements of the valve member.

Abstract: A programmable system controller stores in memory a sequence of program words directly simulating a planar ladder diagram characterizing the desired operation of a controlled system. The ladder diagram is a set of n rung-by-m column arrays of contacts interconnected with particular controlled devices of the system. The program words are read out of the memory in a sequence to directly represent the ladder diagram on a rung-by-rung basis for each column. The controller includes an interface unit coupled to a set of input switches for providing switch signals that are indicative of the operating status of the machine. A data processing unit is provided with an accumulator having a plurality of at least n storage units respectively corresponding to each rung of the ladder diagram.

Abstract: A direct current motor control system for generating current command signals to a unidirectional armature controller and a bidirectional field controller. A motor speed command is compared with the actual motor speed to generate a speed error signal. The system generates a current command signal from the average of the speed error signal wherein the current command signal is proportional to the square root of the desired motor torque. The absolute value of the current command signal is the input to the armature controller and the field controller receives the current command signal wherein the polarity of the signal determines the direction of current flow in the field winding for controlling the direction of rotation of the motor.

Abstract: A controlled glassware-forming machine is disclosed which has a plurality of individual machine sections each capable of individually forming glassware. Fluid actuators such as pneumatic pistons and cylinders are connected to move the various machine elements within each of the individual sections. These actuators are used to open and close the molds and to move the invert-revert arms, for example. The initiation of the movement of these machine elements is by way of a plurality of main valves to start and stop the movements. These valves are controlled by solenoids in turn controlled by electronic outputs of a computer or control means. The speed of movement of the machine elements is controlled by variable aperture valves such as needle valves, and a power means is provided to vary the aperture of such needle valves, also controlled by outputs of the computer.

Abstract: An improved electronic apparatus for accurately weighing, computing a value and printing a label showing the weight, the price per unit weight and the computed value of each of a plurality of successive articles. The scale generates a predetermined number of significant weight digits which are used in computing values and at least one additional least significant weight digit. A digital indicator is provided for normally displaying the significant digits of the corrected net article weight obtained from the measured gross article weight less the zero correction factor and any tare weight. The displayed weight may be shifted and the correcting of errors inhibited to permit displaying the additional least significant weight digit while checking or manually aligning the zero of the uncorrected scale output.

Abstract: A dry fluid drive having a housing with a center axis about which the housing rotates, and a cavity therein concentric with the housing, a dry fluid in the cavity, and a rotor with two spaced sections disposed in the cavity with the hub of the rotor in alignment with the center axis of the housing. A reaction vane of generally annular configuration is connected to the housing at the periphery of the cavity and extends inwardly from the periphery between the rotor sections. The reaction vane is provided with openings such as spaces, notches or holes to facilitate uniform distribution of the dry fluid in the cavity as the housing accelerates to full operating rotational speed. The vane may be of either a straight or undulated configuration, and in the latter configuration, the grooves and ribs increase in magnitude from the outer periphery toward the center.

Abstract: A self cleaning pulley for conveyor belts in which a layer of elastomeric material such as polyurethane is applied to a cylindrical steel member, the layer having a plurality of generally longitudinally positioned resilient ribs extending radially outwardly from the body and spaced uniformly around the periphery thereof. The spaced ribs define generally longitudinally spaced grooves for receiving foreign material carried between the pulley and the belt. The surface of the body between the ribs slopes from a point near the longitudinal center of the pulley inwardly toward the opposite ends to assist in the flow of material dislodged from the belt and pulley to travel to the ends of the pulley where it is discharged. The ribs are resilient but firm and are of such a shape that they will produce a scraping and vibrating action on the belt to dislodge any foreign material between the pulley and belt, causing it to be moved along the grooves of the pulley and to be discharged therefrom.

Abstract: This invention relates to an improved digital weight measuring and computing apparatus with automatic zero correction which automatically corrects the zero indication of the apparatus.The weight measuring apparatus comprises a scale which employs a load cell and strain gauge to develop an analog voltage representing the weight on the scale. An analog-to-digital converter is then employed to change the analog voltage into a digital representation of the load on the scale. The digital converter provides a digital indication in addition to the digital indications employed to indicate the weight on the scale. The additional digital indication represents fractions of the least weight increment indicated of the weight on the scale. The additional digital indication is then employed to control the generation of a zero correction factor and this factor is then combined with the weight indications from the scale to indicate the correct weight of articles placed on the scale.

Abstract: Improved electronic scale system for weighing, computing a value and printing a label showing the weight, price per unit weight and the computed value for each of a plurality of successive articles. An integrated circuit microcomputer is periodically supplied with the article weight from a load cell scale and is supplied with the price per unit weight either from a manual keyboard or automatically from a commodity plate in a label printer. After the system corrects for scale error, checks for scale no motion, compensates for any tare weight and checks various interlocks, the microcomputer computes an article value. A no motion signal is generated by the microcomputer when a predetermined number of successive weight measurements deviate from one another by no more than a predetermined small fractional weight less than the least significant weight digit used by the microcomputer in computing an article value.

Abstract: An adjustable valve assembly as disclosed wherein a plurality of valve blocks may be stacked or ganged side by side, and each used to control a machine part. Each valve block has a solenoid actuated valve to control flow of fluid such as air into a piston and cylinder assembly to move a part of the machine. The air flow is adjustably throttled by a needle valve in either the forward stroke or return stroke of the machine part. The needle valve has a normal at-rest position and may be moved in two directions toward opening and toward closing to establish a variable orifice in the valve block. First and second line shafts extend transversely to all of the various valve blocks for actuating the needle valves in the several valve blocks. Such actuation includes for each valve block first and second drive trains from the line shafts to the needle valve member with first and second clutches in the first and second drive trains and selectively actuable for opening and closing movements of the valve member.

Abstract: A drive system is disclosed which is particularly suitable for use in the glass industry. The drive system is for a plurality of conveying mechanisms to support and to move a load which may be discrete glass objects or a strip or sheet of glass. An electrical line shaft is created by using a plurality of squirrel cage synchronous motors which are connected to drive the conveying mechanisms, whether they be transfer mechanisms for discrete objects or rolls for conveying the strip of glass. One or more electrical inverters supply power to the motors so that not only are the motors operated in synchronism but also in phase register. Thus where discrete glass objects are conveyed the phase register of the transfer mechanisms between glass machines prevents glass breakage, and where rolls are conveying a strip of float glass, the phase register prevents difference in phase rotation of the rolls which could mar the surface of the float glass.

Abstract: A sensing circuit using a polarity discriminator with feedback means for selecting one polarity component of a bi-polar non-symmetrical waveshape signal input, while rejecting the opposite polarity component. The circuit operates on both the amplitude and the frequency characteristics of the input signal, to produce an output signal responsive to these characteristics. The circuit may be used to process signals generated from toothed wheels by electromagnetic sensors, or the like, typically used in tachometer control.

Abstract: A tachometer for generating a digital output signal representing velocity which is a stepped approximation to a 1/t velocity versus time curve where t is the time required to travel a fixed distance. High resolution is obtained by dividing the 1/t curve into octaves and an approximate straight line portion. A nonlinear counter counts a predetermined number of pulses during each octave as the time of the counting interval for succeeding octaves is doubled. Therefore, the counter total and the number of octaves completed after time t represents velocity. After completing eight octaves, the nonlinear counter counts at a predetermined frequency to generate a straight line approximation of the 1/t curve as it approaches zero velocity. The digital output can be converted to analog form by a digital-to-analog converter and operational amplifiers having an amplification factor determined by the number of octaves completed.