摘要:
Means to control feeding of a multi-strike ink ribbon (19) housed in a reversible cassette (12) is disclosed. The cassette carries a magnetisable element (20; 30,31) and when the cassette is inserted in printing apparatus (10, 26) the element is located in operative alignment with a magnetic sensing device (21; 32,33) and with an electromagnet (25; 34). Upon insertion of the cassette, the polarity of magnetisation is sensed and provided the polarity is correct printing is enabled. If the polarity is incorrect printing is disabled. When the end of the ink ribbon is sensed, the electromagnet (25; 34) is energised to reverse the polarity of magnetisation of the element (20) so that when the cassette is removed and re-inserted with reversed orientation, the correct polarity of magnetisation is sensed and printing is enabled. A counter may be provided to limit the number of permitted reversals of the cassette.
摘要:
Means to control feeding of a multi-strike ink ribbon (19) housed in a reversible cassette (12) is disclosed. The cassette carries a magnetisable element (20; 30,31) and when the cassette is inserted in printing apparatus (10, 26) the element is located in operative alignment with a magnetic sensing device (21; 32,33) and with an electromagnet (25; 34). Upon insertion of the cassette, the polarity of magnetisation is sensed and provided the polarity is correct printing is enabled. If the polarity is incorrect printing is disabled. When the end of the ink ribbon is sensed, the electromagnet (25; 34) is energised to reverse the polarity of magnetisation of the element (20) so that when the cassette is removed and re-inserted with reversed orientation, the correct polarity of magnetisation is sensed and printing is enabled. A counter may be provided to limit the number of permitted reversals of the cassette.
摘要:
A bidirectional ribbon drive in which a pair of stepper motors (20, 21) have their windings (30-33, 50-53) crosscoupled so that a drag current flows through one stepper motor to apply drag torque to the ribbon when the other stepper motor is operated for driving. Cross-coupling connections include diodes (66-69, 73-76) and resistors (71,72,78,79) which determine current and thus drag. Applicable for, e.g., an ink ribbon in a printer.
摘要:
A bidirectional ribbon drive in which a pair of stepper motors (20, 21) have their windings (30-33, 50-53) crosscoupled so that a drag current flows through one stepper motor to apply drag torque to the ribbon when the other stepper motor is operated for driving. Cross-coupling connections include diodes (66-69, 73-76) and resistors (71,72,78,79) which determine current and thus drag. Applicable for, e.g., an ink ribbon in a printer.
摘要:
La commande et le contrôle de l'entraînement du ruban sont réalisés par le bloc de commande (300) comprenant un élément de commande (301) qui délivre des signaux d'entraînement aux moteurs (49, 50) entraînant les bobines réceptrices du ruban, par l'intermédiaire des étages de commande analogique (302,303). Si l'une des bobines réceptrices n'est pas entraînée (absence de ruban ou mou du ruban), aucun signal n'est délivré sur les lignes (305 et 306) et l'élément (301) commande l'inversion du déplacement du ruban. Cette commande d'inversion se répète soit jusqu'à l'apparition d'un signal sur les lignes (305 ou 306) indiquant que le ruban est normalement tendu, soit pendant un nombre de fois déterminé, l'élément (301) engendrant alors un signal de mauvais fonctionnement sur la ligne (305).