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US 4,852,481 AGranted
Print hammer mechanism
AssigneesL. James Hubbard, Virginia M. Hubbard
InventorsRonald J. Kobryn, Justin Gaskins
Life of this patent
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AssigneesL. James Hubbard, Virginia M. Hubbard
InventorsRonald J. Kobryn, Justin Gaskins
Estimating the term…
A print hammer mechanism for use in an impact printer such as a band printer or other printer which has printing elements which are impacted to make impressions on paper or other record medium. The hammer of the mechanism is impacted by dual armatures in forward motion toward the paper and return motion away from the paper so that the hammer is positively driven and does not depend upon the bounce back of the hammer from the paper or need a return spring on the hammer. This reduces the time for each hammer stroke and increases printing speed (characters per second). The armatures are normally decoupled from the hammmer and strike the hammer only after accelerating sufficiently to transfer sufficient speed to the hammer upon impact therewith. Springs are used to bias the hammer to a home position in the return direction and to maintain the armatures against a stop spaced from the hammer so that the armatures are normally decoupled from the hammer. The spring forces are light; forward and return hammer drive being provided by the armatures. A magnetic field structure for independently actuating each armature can be used for actuating the hammer in timed relationship with printing operations.
A print hammer mechanism comprising a print hammer moveable toward and away from a printing position, first and second armatures moveably disposed for engagement with said hammer, and means for mounting said first and second armatures in non-interfering relationship with said hammer until engagement therewith to drive said armatures toward and away from said printing position, said spacing being sufficient to enable said armatures to accelerate prior to contacting said hammer in impact delivering relationship and means for actuating said armatures into motion.
A print hammer mechanism comprising a hammer moveable in forward and return directions, first and second armatures for moving said hammer in said forward and return directions, respectively, said hammer having a first surface opposed to said first armature and a second surface opposed to said second armature, said first and second surfaces respectively facing in different ones of said forward and return directions, means mounting said first armature for movement between first and second positions where said first armature is spaced from said first surface and where said first armature is in contact with said first surface, means mounting said second armature for movement between third and fourth positions where said second armature is spaced from said second surface and where said second armature is in contact with said second surface, said spacing being sufficient to enable said armatures to accelerate prior to contacting said hammer in impact delivering relationship, means for actuating said first and second armatures independently for impacting said hammer to drive it in the forward direction to printing position and then in the return direction after said hammer has reached the printing position.
In a printer having printing elements for printing by impact of the elements against a record medium and having a print hammer mechanism including at least one print hammer for impacting upon the printing elements, an improved actuator for said print hammer comprising a pair of armatures normally spaced from and moveable into contact with said hammer for driving said hammer in forward and return directions against and away from said print elements, said spacing being sufficient to enable said armatures to accelerate prior to contacting said hammer in impact delivering relationship and means for independently actuating said armatures.
Dependencies are inferred from the claim text.