JPH0723014B2 - Printer automatic paper feeding method - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic paper feeding method for a printing apparatus. 2. Description of the Related Art Conventionally, in a printing device such as a typewriter, a printer or a word processor, a platen is manually rotated, a sheet for printing is wound around the platen and the sheet is inserted, and then the platen is used. Manually release the pressure contact with the pressure roller, set the paper in a free state, manually overlap the leading edge line and the trailing edge line of the paper, and visually check the parallelism of the paper. The platen and the pressure roller were pressed against each other and the paper was aligned to complete the setting of the paper in the printer. SUMMARY OF THE INVENTION It is an object of the present invention to provide an automatic sheet feeding method which eliminates the troublesome work of setting the sheet and stably feeds the sheet to the printing means. To do. According to the present invention, the above objects are achieved by a platen for feeding paper, a platen driving means for driving the platen, a first position away from the platen, and the paper. A paper bail that moves between a second position for pressing the platen, a control unit that controls the operation of the platen driving unit, and a storage unit that stores a fixedly determined paper feed amount. In a printing device comprising desired print start position setting means capable of setting a desired print start position, when setting the paper by driving the platen by the platen drive means controlled by the control means, In tandem with the movement operation to the first position, the paper is fed by the fixed amount of the first movement stored in the storage means, and the second of the paper bail is fed. This is achieved by further interlocking with the movement operation to the position, and feeding the paper by the second movement amount based on the set value set by the desired print start position setting means. Further, in order to achieve the above-mentioned object, the present invention proposes that the desired print start position setting means is a setting means that represents the distance to the desired print start position or the number of lines by a numeral. . [0006] In tandem with the movement of the paper bail to move to the first position away from the platen, the paper is fed by the fixed amount of the first movement stored in the storage means, and the paper of the paper bail is fed. The paper is printed by a method of sending the paper by a second moving amount based on the set value set by the desired print start position setting means in conjunction with the movement operation to press the platen to the second position. To feed. The details of the present invention will be described with reference to the embodiments shown in the drawings. In FIG. 1, the paper 3 stored in the cassette 2 installed in the automatic paper feeder 1 is fed by a start command from the controller of the printer 4. That is, the motor 5 is driven by the start command, the hopper roller 6 is rotated in the direction of the arrow, and the paper 3 is frictionally fed by being pressed by the hopper roller 6 that rotates the paper 3 by the pushing-up member 7. . The paper 3 is separated by the action of the separation claw 8, and only the uppermost one sheet of paper is fed along the guide member 9 toward the platen 10 of the printer 4. Platen 10 and first pressure roller 1
After the tip of the paper comes into contact with the contact point of 1, the paper is fed by an extra amount by the hopper roller 6,
As shown by the broken line in the figure, the paper is bent. The extra amount of feeding the paper is set so as to correspond to the distance rθ from the contact point of the platen 10 with the first pressure roller 11 to the contact point with the second pressure roller 12. In this case, r is the radius of the platen 10, and θ is the angle formed by the contact point between the platen 10 and the first pressure roller and the contact point between the platen 10 and the second pressure roller with respect to the center of the platen 10. After feeding the excess amount, the rear hopper roller 6 is stopped, and thereafter, a command is given to rotate the platen by an amount corresponding to the number set in the indicator 13 provided in the automatic paper feeder 1. 10 rotates. The pressing force of the first pressure roller 11 is weakened so that wrinkles do not occur when the paper 3 is fed to the printing position by the rotation of the platen 10. Even if the pressing force of the first pressure roller 11 is weak, since the paper is bent as shown by the broken line, the paper can be fed without being affected by the load of the hopper roller 6. The second pressure roller 12 does not cause wrinkles even if the pressing force is strong. Therefore, if the pressing forces of the first pressure roller 11 and the second pressure roller 12 are properly designed, the paper is placed on the platen. Paper can be fed without causing slippage or wrinkling. It is convenient to use a one-way clutch 14 or the like so as to reduce the load on the hopper roller 6 when the paper is fed by the platen 10. The paper fed by the rotation of the platen 10 is
After passing through the second pressure roller 12, it is guided by the paper guide 15 on the movable carriage having the printing means which is moved to the center of the printing device 4 in advance, and moves upward. By moving this carriage,
The paper that is fed is easily guided by the paper guide on the carriage inside the paper.Therefore, when there is no carriage at the position corresponding to the paper, the paper floats from the platen, or the carriage near one edge of the paper. If there is, it is possible to prevent the edge of the other paper from largely floating from the platen. At the same time as the rotation of the platen 10, the magnet 16 is excited, the arm 17 is moved to the left in the figure, and the paper bail 18 is moved to the position shown by the chain line.
The paper advances to a specified position without being obstructed by the paper bail 18, where the magnet 16 is de-energized, the paper bail 18 retreats, and presses the paper against the platen 10. When the paper pressed by the paper bail 18 reaches the print start position designated by the operator, the platen 10
Stops. The carriage returns to the home position, and the print wheel 19 provided on the carriage in response to the print signal.
Printing is performed by the action of the hammer 20. The printed paper is sequentially sent upward along the front guides 21 and 22, and is sent to the stacker 24 by the paper discharge roller 23. The indicator 13 comprises, for example, a numeral ring 25 as shown in FIG. 2, a contact 26 is attached as shown in FIG. 3, and the contact of the printed circuit board 27 with which the contact 26 comes into contact by rotation of the numeral ring 25. 27a are sequentially changed, and a signal corresponding to the numeral is output according to the contact of the printed circuit board 27 with which the contact 26 of the numeral ring 25 comes into contact. This signal is output by the coder 28 as shown in FIG. Code. The indicator 13 represents the distance from the set position determined by the paper device to the position where printing is to be performed, the number of lines, and the like by numbers. The code signal indicating the distance from the set position to the print position and the feed amount 29 indicating the distance from the contact point of the first pressure roller 11 to the set position, which is determined in advance by the device, are fed to the coder 3
The signal coded by 0 is added by the adder 31, the platen drive motor 32 is operated by the added amount, and the platen 10 is rotated by the amount added by the adder. According to the present invention, it is possible to reduce the risk of jamming and to stably feed paper to a desired position.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an explanatory diagram of a printing apparatus to which the method of the present invention can be applied. FIG. 2 is a front view of an indicator. FIG. 3 is an explanatory diagram of an indicator. FIG. 4 is a control block diagram of the sheet feeding device according to the present invention. [Explanation of Codes] 1 ... Cassette 3 ... Paper 6 ... Hopper roller 10 ... Platen 11 ... First pressure roller 12 ... Second pressure roller 13 ... Indicator 19 ... Printing wheel 20 ... Hammer

Claims (1)

(1) A platen for feeding a sheet of paper, a platen driving means for driving the platen, a first position separated from the platen, and a second position for pressing the paper against the platen. A paper bail that moves between the two, a control means that controls the operation of the platen drive means, a storage means that stores a fixedly determined paper feed amount, and a desired print start position that can set a desired print start position. In a printing device comprising a setting means, when setting the paper by driving the platen by the platen driving means controlled by the control means, in conjunction with a movement operation of the paper bail to a first position, The paper is further fed by a fixedly fixed first movement amount feed stored in the storage means, and the paper bail is further interlocked with the movement operation to the second position. Automatic paper feeding method of printing apparatus characterized by serial was to send the second movement amount based on the values set in the desired printing start position setting means. (2) The sheet feeding method according to claim 1, wherein the desired print start position setting means is a setting means that represents a distance to the desired print start position or the number of lines by numbers.