| 摘要 |
<p>A micro computerized, miniature postage meter comprises an ink jet printing device adapted to project ink droplets onto a document. A micro computer, which performs the control and data processing functions of the meter, includes a logic circuit programmed to actuate the ink jet printing device to project ink droplets on the document in a postage indicia forming pattern. In the preferred form of the postage meter, the ink jet printing device is mounted to be moved in close operative proximity relative to the document and the logic circuit is programmed to sequentially actuate the printing device during this relative movement. The rate of movement of the printing device relative to the document is observed by an optical monitor, mounted with the printing device. The micro computer also includes a clock circuit, connected to the optical monitor, that computes the instantaneous rate of relative movement of the printing device and document and then generates a feedback signal to the logic circuit to coordinate the instantaneous rate of actuation of the printing device to the computed instantaneous rate of relative printing device-document movement. A postage memory register stores a purchased amount of postage and is addressable by the logic circuit to reduce the stored amount of postage by the amount printed during each meter use. A disabling lock-out circuit disables the meter when postage stored in the memory register is depleted to a predetermined minimum amount.</p> |
