Abstract: A current source inverter power supply for an ozone generator which results in improved efficiency and reliability in operation of such generators has an AC/DC converter coupled through a large inductance to a DC/AC inverter that, in turn, is coupled at its output to the primary of a high voltage transformer. Such transformer has an air gap in its core to supply the electrical characteristics necessary for resonance with the load which is capacitive in nature. Thyristors in the inverter are naturally commutated so the switching frequency is close to, but slightly above, the natural resonant frequency of the inverter/transformer/ozone generator circuit.

Abstract: A current source inverter power supply for an ozone generator which results in improved efficiency and reliability in operation of such generators has an AC/DC converter coupled through a large inductance to a DC/AC inverter that, in turn, is coupled at its output to the primary of a high voltage transformer. Such transformer has an air gap in its core to supply the electrical characteristics necessary for resonance with the load which is capacitive in nature. Thyristors in the inverter are naturally commutated so the switching frequency is close to, but slightly above, the natural resonant frequency of the inverter/transformer/ozone generator circuit.

Abstract: A meter base drive assembly (4) is a part of a postage meter base (2), to which a postage meter is mounted. The assembly includes envelope drive (62), a tape dispenser (86) and a print head drive (84) mounted to a base frame (12). The drive assembly includes a motor drive (6), pivotally mounted (10, 14) to the frame, which drive a pulley (8) in a first rotary direction. First, second and third driven pulleys (16, 18, 56) are operably coupled to the envelope drive, print head drive tape dispenser respectively. A dual pulley (20), including first and second ppulley element (28, 53), is pivotally mounted (34, 36; 102, 104) to the frame. One side (30) of a first drive belt (26) engages the drive pulley and the second driven pulley. The second side (32) of the first drive belt engages the first pulley element. A second drive belt (52) engages the second pulley element and the second driven pulley so that the first and second driven pulleys are rotated in opposite rotary directions.

Abstract: An assembly for preventing reverse rotary rotation of a disc includes openings having circumferentially spaced-apart ends formed in the disc. The leading end has an abutment surface perpendicular to the plane of rotation of the disc. The trailing end of the opening is ramped. Pins are mounted to a stationary support opposite the openings in the disc and are biased toward the disc. The outer end of each pin is sized to fit within the openings and has an abutment surface oriented perpendicular to the plane of rotation of the disc and configured for complementary mating engagement with the abutment surface defining the forward edge of the opening. The outer end of the pin is an angled or ramped surface. Forward rotation of the disc causes the two ramped surfaces to engage, biasing the pin away from the disc. The pin then slides along the surface of the disc until another opening is encountered at which time the process is repeated.

Abstract: A value wheel rod lock is used to selectively lock value rods, mounted to a rotatable shaft of a postage meter, against axial movement according to the rotary position of the shaft. The rod lock includes a knife blade pivotally mounted to the shaft for rotation with the main shaft. The knife blade is spring biased away from engagement with the value rods. The knife blade is mounted to a cam follower which engages a circumferential cam surface surrounding the shaft. The cam surface is configured so that over a range of angular positions of the shaft the knife blade is biased against the value rods. This forces the value rods against a high friction backing pad mounted to the shaft with sufficient force to keep the value rods from being moved axially. When the shaft is at its home position, during which the meter values can be changed, the knife blade is biased away from the value rods to allow the value rods to be freely movable.