Serial impact calculator printer with dual feed and validation mechanism
AssigneeEaton Corporation
InventorDean H. Cranston
Life of this patent
Estimating the term…
Abstract
A printer having a movable print head for printing on a first record medium fed by one feed mechanism also contains a second feed mechanism capable of performing line-by-line feeding of a separate record medium across the print head independently of the main drive and is capable of performing single line or multi-line printing on the separate record medium.
Claims20
In a printer having a frame upon which is mounted a pair of record media advancing rollers having external surfaces engageable with one another to form a guide path for advancement of a record medium therebetween and into position for impression of characters thereon by a print head, the improvement comprising:
- incremental drive means associated with one of said record medium drive rollers including a ratchet member mounted on said one recording medium drive roller and indexing means having a pivotal feed pawl of generally U-shaped configuration, said feed pawl defining a drive arm and limit arm movable into engagement with circumferentially spaced teeth on said ratchet member, said indexing means including means normally urging said drive arm and limit arm into engagement with said ratchet member, releasing means selectively energizable to advance said drive arm and limit arm away from engagement with said ratchet member, said indexing means operative when said releasing means is de-energized to move said drive arm into engagement with one of said ratchet teeth to advance said one record medium advancing roller a limited distance prior to engagement by said limit arm with a circumferentially spaced tooth on said ratchet member to prevent further advancement of said one record medium advancing rollers.
In a printer apparatus wherein a first line feed mechanism controls the advancement of a record medium past a stationary print bar in correlation with the lateral line printing movement of a print head, the improvement comprising:
- a document feed mechanism for selectively controlling the indexing of a document superimposed on the record medium independently of said line feed mechanism past said print head, said document feed mechanism having means establishing a guide path for insertion of a document between said print bar and said print head, said last named means including document advancing rollers provided with external surfaces engageable with one another on said guide path;
- and
- incremental drive means associated with one of said document advancing rollers including a ratchet member mounted on said one roller and indexing means having a pivotal feed pawl of generally U-shaped configuration movable into engagement with circumferentially spaced teeth on said ratchet member, and feed pawl drive means selectively energizable to control movement of said feed pawl with respect to said ratchet member whereby to effect line feeding of said document along said guide path independently of line feeding of said record medium.
In a printer having a frame upon which is mounted a pair of record media advancing rollers having external surfaces engageable with one another to form a guide path for advancement of a first record medium therebetween and into position for impression of characters thereon by a print head, the combination therewith comprising:
- a first line feed mechanism associated with one of said record medium drive rollers including a ratchet member mounted thereon and indexing means having a pivotal feed pawl provided with a drive arm and limit arm movable into engagement with circumferentially spaced teeth on said ratchet member, means normally urging said drive arm and limit arm into engagement with said teeth, releasing means selectively energizable to advance said drive arm and limit arm away from engagement with said ratchet member, said drive means operative to move said feed pawl into engagement with said ratchet member when said release means is de-energized whereby said drive arm is caused to move into engagement with one of said ratchet teeth to advance said record medium advancing roller a limited distance prior to engagement by said limit arm with a circumferentially spaced tooth on said ratchet member;
- and
- a second line feed mechanism for selectively controlling line feeding of a second record medium independently of said first line feed mechanism past said print head, said second line feed mechanism having means establishing a guide path for insertion of the second record medium between said print bar and said print head, said last named means including pressure feed rollers provided with external surfaces engageable with one another on said guide path, incremental drive means associated with one of said pressure feed rollers including a ratchet member mounted on said one roller and indexing means having a pivotal feed pawl of generally U-shaped configuration movable into engagement with circumferentially spaced teeth on said ratchet member, and feed pawl drive means selectively energizable to control movement of said feed pawl with respect to said ratchet member whereby to effect line feeding of said second record medium along said guide path independently of line feeding of said first record medium.
Dependencies are inferred from the claim text.