摘要:
For a stepping motor having a rotatable stator magnetic field for driving the rotor, there is disclosed a method of damping the oscillations of the rotor which occurs when the rotatable stator magnetic field is stopped upon arriving at a desired rotational position by measuring quantities related to the instantaneous velocity of the rotor due to the oscillations of the rotor about the desired rotational position, rotationally displacing the stator magnetic field from the desired rotational position in a direction opposite to the direction of the oscillation, and thereafter returning the stator magnetic field to the desired stopping position.
摘要:
A paper tray having a bottom, front and rear walls extending upwardly from the bottom, and side walls extending upwardly from the bottom to define an open boxlike structure for storage of sheets of paper in readiness for use. A paper receiver is pivotably mounted on the tray for receiving sheets of paper after printing thereof. The paper receiver has a first position in which paper can be fed automatically from the tray to a print roller and a second position in which paper can be manually fed to the print roller. In the automatic mode, the paper is fed by a drive roller to produce a buckle at its leading position to insure alignment at the print roller and subsequent straight, unskewed feed. The paper receiver carries a conveyor belt driven from the print roller at a greater linear speed to insure positive feed of the paper from the print roller to a receiving station.
摘要:
A method of stopping a feedback-controlled stepping motor having a stator and a rotor wherein the drive of the stator field is leading the rotor by more than one step and the rotor is rotating with an angular velocity within a first range of values is performed by decreasing the drive lead of the stator field from its slewing value to another value whereby the angular velocity of the rotor decreases below the first range and sensing for the decrease of the angular velocity of the rotor to within a second range of values so that when the angular velocity of the rotor is within the second range of values the rotation of the stator field is stopped to brake the rotor.
摘要:
A paper tray has a first bottom, first front and rear walls extending upwardly from the first bottom, first and second side walls extending upwardly from this bottom. The walls and bottom define an open boxlike structure for storage of sheets of paper prior to use. A cover is pivotably mounted to the top of the lower side walls in the region of the rear wall extends toward the first front wall. The cover is shorter than the first bottom to provide a feed gap between the free end of the cover and the front wall so that paper can be removed from the boxlike structure. Each of the lower side walls has an extension upwardly extending beyond the level of the cover. Paper receiving means has a second bottom upwardly displaced from and overhanging the feed gap and the front wall. First and second upper side walls are connected to the ends of the extensions remote from the rear wall and extend upwardly from the upper bottom. A front wall extending upwardly from the edge of the second bottom remote from the connection to the extensions. The second bottom, the upper side walls and front wall define a receptacle for receiving after use sheets of paper initially stored in the defined open boxlike structure.
摘要:
Apparatus for recording characters on a photographic record medium including spaced feed and takeup reels for carrying a roll of the medium. A support such as a cylinder is disposed between the reels supports the record medium. A carriage is controllably movable opposite the support and in a direction transverse to the direction of record medium movement. A recording head on the carriage has a radiation emitter device for emitting intensity modulated radiation toward the cylindrical support along a scan line which makes an angle with the direction of the transverse movement.
摘要:
A clock generator for establishing working clock pulses occurring for constant increments in a scan path of a laser scanner which cyclically sweeps over a record medium at a non-constant velocity includes: a generator of a fiducial pulse at least once per cycle of sweep; a frequency synthesizer responsive to the fiducial pulses for generating radio-frequency clock pulses having a frequency greater than the fiducial pulses, and in synchronization therewith; a storage for storing a plurality of count values, each of the count values being associated with a given increment along the scan path; a working clock pulse generator, including a counter which counts the radio-frequency clock pulses, for emitting a working clock pulse each time the counter counts a count value received by the working clock pulse generator. For each working clock pulse a new count value stored in the storage is transmitted to the working clock pulse generator.
摘要:
Apparatus for recording characters on a photographic record medium including spaced feed and takeup reels for carrying a roll of the medium. A cylindrical support disposed between the reels supports the record medium. A carriage is controllably movable opposite the cylindrical support and in a direction along the cylindrical axis of the latter. A recording head on the carriage has a radiation emitter device for emitting intensity modulated radiation toward the cylindrical support along a scan line which is in a plane intersecting such cylindrical axis.
摘要:
A vibrating thermal printer transfers thermoplastic ink from a ribbon to a record medium by selectively heating resistive elements on a substrate of electrically conductive material. While the record medium and ribbon are passing the print head, the print head, by means of piezoelectric phenomenon, induces vibration in the head to facilitate the deposition of thermoplastic ink onto the paper. There is also shown the preheating of the ribbon to improve throughput.
摘要:
A stepping motor-driven system includes a stepping motor, an output device, and a belt and pulley system operably coupling the stepping motor with the output device to impart rotation therebetween. The belt and pulley system includes an input pinion engaged with the stepping motor, an output pinion engaged with the output device, and a timing belt. The timing belt is disposed about the input and output pinions, inhibits elongation, and defines a plurality of spaced-apart grooves on an inwardly-facing surface thereof that are wider than the teeth of the pinions and are configured to receive the teeth of the pinions in meshed engagement therewith. As a result, a gap is defined within each groove. The gaps permit backlash of the timing belt in response to changes in a rotational speed input to the belt and pulley system from the stepping motor, thereby inhibiting loss of control.
摘要:
An ink ribbon cartridge for a printer comprising a storage reel for an ink ribbon, a take-up reel for the ink ribbon, drive wheels for longitudinally advancing the ink ribbon from the storage reel to the take-up reel for printing on the ribbon, and a pulley or roller which rides on the cam and which is coupled to a further pulley or roller, these parts cooperating for transversely displacing the ribbon during its longitudinal advance to offset the area of the ribbon utilized in printing.