Abstract: A method for testing the integrity of a stack during ultrasonic welding, includes the steps of: (i) ultrasonically welding two or more work pieces with a stack, the stack including a convertor and a horn; (ii) measuring a frequency profile based on a vibration of the horn during the welding step; and (iii) comparing the measured frequency profile to a standard frequency profile to obtain an error rate, the error rate being indicative of a difference between the measured frequency profile and the standard frequency profile. A system employing the aforementioned method is also provided.

Abstract: A method for testing the integrity of a stack during ultrasonic welding, includes the steps of: (i) ultrasonically welding two or more work pieces with a stack, the stack including a convertor and a horn; (ii) measuring a frequency profile based on a vibration of the horn during the welding step; and (iii) comparing the measured frequency profile to a standard frequency profile to obtain an error rate, the error rate being indicative of a difference between the measured frequency profile and the standard frequency profile. A system employing the aforementioned method is also provided.

Abstract: An ultrasonic welder for splicing a plurality of workpieces has four anvils, each formed with a meeting surface and displaceable to form a workpiece nest, which has a rectangular shape of a predetermined width. The width of the workpiece nest is sufficient to receive only at least one vertical column of workpieces to be welded, so as to produce a vertical splice. The ultrasonic welder further has a controller controlling a starting position of tooling, which forms the predetermined width of the workpiece nest, and displacing at least one of tools, which form side faces of the nest in reciprocal and time controlled manner. The displaceable tool is brought back to its starting position corresponding to the predetermined width of the workpiece nest before a new bundle of workpieces is loaded therein.

Abstract: An ultrasonic welder for splicing a plurality of workpieces has four anvils, each formed with a meeting surface and displaceable to form a workpiece nest, which has a rectangular shape of a predetermined width. The width of the workpiece nest is sufficient to receive only at least one vertical column of workpieces to be welded, so as to produce a vertical splice. The ultrasonic welder further has a controller controlling a starting position of tooling, which forms the predetermined width of the workpiece nest, and displacing at least one of tools, which form side faces of the nest in reciprocal and time controlled manner. The displaceable tool is brought back to its starting position corresponding to the predetermined width of the workpiece nest before a new bundle of workpieces is loaded therein.

Abstract: An ultrasonic welder for splicing a plurality of workpieces has four anvils, each formed with a meeting surface and displaceable to form a workpiece nest, which has a rectangular shape of a predetermined width. The width of the workpiece nest is sufficient to receive only at least one vertical column of workpieces to be welded, so as to produce a vertical splice. The ultrasonic welder further has a controller controlling a starting position of tooling, which forms the predetermined width of the workpiece nest, and displacing at least one of tools, which form side faces of the nest in reciprocal and time controlled manner. The displaceable tool is brought back to its starting position corresponding to the predetermined width of the workpiece nest before a new bundle of workpieces is loaded therein.

Abstract: An ultrasonic welder is provided which automatically recognizes and reliably welds varying weld zone sizes of material The welder comprises a base, a transducer, a tip, an anvil, a gathering tool, and an actuator for moving both the anvil and gathering tool to define a weld zone. An encoder reads movement of the actuator and a microprocessor determines weld zone size to control the transducer for maximizing weld efficiency. Preferably, a horn is mounted between the transducer and tip and the horn is dynamically mounted along an axis of the transducer to transmit the maximum amount of ultrasonic energy to the weld. In another aspect, the invention relates to a method of operating an ultrasonic welder to automatically recognize and reliably weld varying weld zone sizes.

Abstract: An apparatus to indicate a low level of liquid in a vessel, such as an automobile crankcase. A light-emitting diode and a phototransistor are coupled at the crankcase so that the light received by the phototransistor varies with rising or falling oil levels. The diode has a given maximum current rating. A unique pulse generating circuit applies a short duration, high-current pulse to the light-emitting diode to produce a correspondingly short but intense burst of radiant energy that is received by the phototransistor. The sensitivity of response is superior to that of a phototransistor employed with a light-emitting diode driven by low-level voltages giving rise to currents equal to or less than its steady-state rating. False readings are eliminated when the vehicle is on an incline, or when the ignition switch is improperly operated. Reliable functioning is had, even at high operating temperatures.