Patent Application
20110259163
The present invention relates to the field of cutters for printers. More specifically, the present invention relates to guillotine knife blade type cutters for a printer and methods of cutting paper media in a printer using such guillotine knife blades.
High speed printers, such as inkjet, thermal, dye sublimation and dot matrix printers are used to provide vouchers, coupons, tickets, receipts and the like (all generally referred to herein as “tickets”) to consumers. Such printers typically use a roll of paper media which is cut by a cutter. Different types of cutters may be used in such printers, including a rotary cutter or a guillotine knife blade type cutter. The guillotine knife cutters typically employ a fixed blade and a movable blade which is displaced in the direction of, and engages against, the fixed blade during a cutting action after the ticket is printed on the paper media. While such guillotine knife blades are generally simpler and less expensive than rotary knife blades, such guillotine knife blades are prone to jamming and difficult to service. It is also typically difficult to load paper into printers having guillotine knife blades.
It would be advantageous to improve the prior art guillotine knife blade type cutters to provide improved serviceability and reliability, and to enable easy loading of paper and clearance of paper jams. It would be advantageous to enable easy separation of the guillotine knife blades for service and jam clearance.
The cutting apparatus and methods of the present invention provide the foregoing and other advantages.
The present invention relates to a cutter for a printer having guillotine knife blades that are easily separable, along with corresponding methods for cutting paper media using such knife blades.
In one example embodiment of the invention, a cutter for a printer is provided. The cutter comprises a fixed blade and a movable blade. The fixed blade is arranged on a cover bracket. The cover bracket is movable between an open and a closed position. The movable blade is arranged on a printer frame. Means are also provided for moving the movable blade from a home position into engagement with the fixed blade for cutting paper media during a cutting action. In the open position of the cover bracket the fixed blade and movable blade are separated, enabling paper jams to be cleared and paper to be loaded.
The movable blade may be V-shaped, enabling side portions of the movable blade to engage with the fixed blade before a center portion of the movable blade engages with the fixed blade. The fixed blade may be bowed in a center section. For example, the fixed blade may be bowed approximately 0.06 inches in the center section.
The means for moving the movable blade may comprise two spaced apart rotating cams which support and lift the movable blade up into engagement with the fixed blade during the cutting action and a drive mechanism for rotating the two cams simultaneously during the cutting action. Return springs may be provided for biasing the movable blade downward into the home position against the operation of the two cams.
A spring-loaded blade bearing may be provided for biasing the movable blade transverse to a cutting plane against a stop when the cover bracket is in the open position. The stop may be located on the frame.
In one example embodiment, corresponding fingers may be provided which extend off of the fixed blade and the movable blade outside of a cutting width of the blades. The fingers serve to guide the blades into engagement with one another during the cutting action. Further, the corresponding fingers of the fixed blade and the movable blade may engage with one another when the cover bracket is in the closed position and the movable blade is in the home position, ensuring proper alignment for the engagement of the movable blade and the fixed blade during the cutting action.
A sensor may be provided for sensing the home position of the movable blade and which is in communication with the means for moving the movable blade.
The movable blade and the fixed blade may be mounted such that the blades are at a slight angle with respect to one another during the cutting action.
The fixed blade and the movable blade may be coated with different ultra-hard coatings such that a differential hardness between the respective coatings is chosen to focus wear on the fixed blade.
The present invention also includes methods corresponding to the above-described apparatus. An example embodiment of a method for cutting paper media in a printer in accordance with the present invention may comprise: providing a fixed blade arranged on a cover bracket, the cover bracket being movable between an open and a closed position; providing a movable blade arranged on a printer frame; and moving the movable blade from a home position into engagement with the fixed blade for cutting the paper media during a cutting action. In the open position of the cover bracket the fixed blade and movable blade may be separated, enabling paper jams to be cleared and paper to be loaded.
The method embodiments of the present invention may also include various features of the apparatus embodiments discussed above.
The present invention will hereinafter be described in conjunction with the appended drawing figures, wherein like reference numerals denote like elements, and:
The ensuing detailed description provides exemplary embodiments only, and is not intended to limit the scope, applicability, or configuration of the invention. Rather, the ensuing detailed description of the exemplary embodiments will provide those skilled in the art with an enabling description for implementing an embodiment of the invention. It should be understood that various changes may be made in the function and arrangement of elements without departing from the spirit and scope of the invention as set forth in the appended claims.
The present invention relates to a cutter for a printer having guillotine knife blades that are easily separable, along with corresponding methods for cutting paper media using such knife blades.
An example embodiment of a cutter 10 for a printer in accordance with the present invention is shown in
The cover bracket 16 may be pivotally connected to the printer frame 18 for pivoting between the open and closed positions, for example at pivot point 21 as shown in
The movable blade 14 may be V-shaped, enabling side portions 22 of the movable blade 14 to engage with the fixed blade 12 before a center portion 24 of the movable blade 14 engages with the fixed blade 12. As shown in
As can be seen from
Return springs 32 may be provided for biasing the movable blade 14 downward into the home position against the operation of the two cams 28.
In one example embodiment, corresponding fingers 40, 42 may be provided which extend off of the fixed blade 12 (fingers 40) and off of the movable blade 14 (fingers 42). The fingers 40, 42 are positioned outside of a cutting width of the blades 12, 14. The fingers 40, 42 serve to guide the blades 12, 14 into engagement with one another during the cutting action.
The corresponding fingers 40, 42 of the fixed blade 12 and the movable blade 14 may engage with one another when the cover bracket 16 is in the closed position and the movable blade 14 is in the home position, ensuring proper alignment for the engagement of the movable blade 14 and the fixed blade 12 during the cutting action. The home position of the movable blade 14 when the cover bracket 16 is closed is shown, for example, in
When the cover bracket 16 is opened and the movable blade 14 returns to an unengaged position (i.e., fingers 40 and 42 are no longer in engagement with one another), the movable blade 14 may be located by the blade bearing 34. The stops 36 prevent the movable blade 14 from being able to freely pivot about the blade bearing 34. These stops 36 may comprise two small protrusions off of the sides of the frame 18 to limit the pivoting of the movable blade 14 and allow for better control when closing the cover bracket 16 and re-engaging the fingers 40, 42 of blades 12 and 14.
A sensor 44 may be provided for sensing the home position of the movable blade 14. The sensor 44 may be in communication with the means for moving the movable blade 14. The sensor 44 may comprise an optical sensor.
The movable blade 14 and the fixed blade 12 may be mounted such that the blades are at a slight angle with respect to one another during the cutting action.
The fixed blade 12 and the movable blade 14 may be coated with different ultra-hard coatings such that a differential hardness between the respective coatings is chosen to focus wear on the fixed blade 12.
In operation of an example embodiment of the cutter 10, when the cover bracket 16 is closed, the movable blade 14 resides in the home position as shown in
In order to ensure edge-to-edge contact of the blades 12, 14 during the cutting action, a tail section 46 of the movable blade 14 is supported at a rear portion 48 of the frame 18 while the cutting edge of the movable blade 14 is position on the fixed blade 12 (which at this point is resting and bowed against the frame 18.) This creates a slight angle between the blades 12, 14 which ensures that the blade cutting edges are in contact during the cut.
It should now be appreciated that the present invention provides improved guillotine knife blade type cutters and corresponding methods.
Although the invention has been described in connection with various illustrated embodiments, numerous modifications and adaptations may be made thereto without departing from the spirit and scope of the invention as set forth in the claims.
