Abstract: Contact plates are provided including a base member and a lid. The base member has a sidewall extending circumferentially around a peripheral edge portion thereof to define a sample receiving area. The lid has a sidewall extending circumferentially around a peripheral edge portion thereof. A plurality of ribs extend from an inner surface of the sidewall of the lid. The ribs are configured to provide an interference fit engagement between the sidewall of the base member and the sidewall of the lid when the lid is attached to the base member.

Abstract: Over-voltage protection circuits are provided for power supplies that may limit input voltage spikes to a power converter and amplifiers including a damping loop that may damp filter resonance. Active damping systems incorporating the over-voltage protection circuits and/or damping loops of the present invention are also provided which may be particularly advantageous in applications such as aircraft or other vehicle applications where size and power consumption are important design considerations. The over-voltage protection circuit in various embodiments senses AC and/or DC voltage levels above a detection threshold level and momentarily disconnects the voltage input to thereby reduce the maximum voltage level input transients seen by the power converter. A capacitor may be provided to maintain the input voltage to the power converter while the input is switched out.

Abstract: Vibration absorbers are provided which utilize a torsional spring and a dynamic mass to control vibrations that occur within the structure to which they are attached. Additionally, pipeline systems are provided which utilize such vibration absorbers including a mass and a torsional spring to control the vibrations that occur within the pipeline system. In various embodiments of the present invention, the torsional spring is one or more elastomer elements coupled between the dynamic mass and a support frame to produce a spring force responsive to pivotal rotation of the dynamic mass relative to the support frame. In various embodiments, one or more elastomer elements arranged in series or in parallel may be used as the torsional spring to provide a desired vibratory dampening characteristic for applications, such as pipelines. Use of such torsional springs may provide a more simplified design with less mechanical joints which may be less susceptible to failure in harsh environments.

Abstract: A point of sale printer includes a magnetic reader for processing transactions and payment by check at a checkout point of a retail establishment. The printer includes a magnetic or MICR reader located at a predetermined point on the printer's document travel path and a print head located at the same point on the document travel path but laterally offset from the MICR reader to allow the printer to print customer receipts and a journal as well as reading MICR information from checks and endorsing the check after it is cleared. A pressure pad is used with the magnetic read head of the MICR reader which utilizes a pressure film which flexes when a document is inserted between the magnetic read head and the pressure film to provide a spring loading force on the magnetic read head while still allowing the document to be moved smoothly past the magnetic read head.