Abstract: A welding system includes a welding power supply, wire feeder, and welding circuit connecting the power supply to the wire feeder. The power supply and the wire feeder are configured for bidirectional communication over the welding circuit. The power supply includes a voltage sensor that measures a voltage level, and a current sensor that measures a current level, on the welding circuit. The power supply is configured to operate in a first welding mode to output a power voltage level to the welding circuit to power the wire feeder in response to a communication from the wire feeder over the welding circuit. The power supply generates periodic voltage dip pulses on the welding circuit, and automatically switches to a second welding mode different from the first welding mode based on the voltage level on the welding circuit falling below a threshold voltage level during a voltage dip pulse.

Abstract: Systems, methods, and apparatus providing advanced controls in a foot pedal device used in arc welding. The foot pedal device is configured to interface with a welding power source and provide one or more selectable modes of operation, allowing an operator to control one or more waveform characteristics of an output welding waveform. The advanced control logic for controlling the one or more waveform characteristics resides in the foot pedal device and is responsive to a depressed position of the foot pedal device. Such a foot pedal device, having advanced controls, allows for the advanced, real-time control of the output of a simple welding power source during a welding process.

Abstract: A system for controlling a welder supports remote operation of the welder by either a hand or a foot of the user. The controls of the system share components such that the user can readily change from hand control of the welder to foot control of the welder and vice versa.

Abstract: A system for controlling a welder supports remote operation of the welder by either a hand or a foot of the user. The controls of the system share components such that the user can readily change from hand control of the welder to foot control of the welder and vice versa.

Abstract: A standing aid for use with a checkout counter to assist an operator of the checkout counter while standing above a floor, comprising a base frame adapted to be mounted above the floor adjacent the checkout counter, a buttocks cushion adapted for engaging the buttocks of the operator of the checkout counter while standing, and support structure mounted to the base frame for movably supporting the buttocks cushion above the floor in a plurality of vertical positions and in a plurality of lateral positions, the buttocks cushion being pivotally mounted to the support structure.

Abstract: A standing aid for use with a checkout counter to assist an operator of the checkout counter while standing above a floor, comprising a base frame adapted to be mounted above the floor adjacent the checkout counter, a buttocks cushion adapted for engaging the buttocks of the operator of the checkout counter while standing, and support structure mounted to the base frame for movably supporting the buttocks cushion above the floor in a plurality of vertical positions and in a plurality of lateral positions, the buttocks cushion being pivotally mounted to the support structure.

Abstract: An improved method and apparatus for heating fluids wherein separate gas streams of natural gas and air are compressed to a preselected pressure, passed to an injection and mixing zone for thorough mixing including expansion of one gas and compression of the other, passed to a combustion chamber for burning with the combustion products being further contracted and passed to a heat exchanger conduit where such combustion products are progressively further contracted as they are brought into heat exchange with the fluid to be heated.

Abstract: Apparatus and method for sorting scrap metal pieces dependent on the type of metal therein. The apparatus includes a conveyor and a feeding arrangement to feed the scrap metal pieces on to the conveyor, together with an X-ray fluorescence detector to examine each metal piece and determine the type of metal as a result of the characteristic X-rays emitted. A respective control signal is utilized to move pegs on the conveyor so as to permit the respective metal piece to exit from the conveyor along a respective path and to enter a bin for that particular type of metal. In this way scrap metal pieces of different metal are collected in different bins for subsequent processing.