JP2890437B2 - Paper feeder - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a paper feeding device such as a printer.

[Prior Art] Conventionally, for example, in a paper feeder of a printer, a separation roller is provided on an upper portion of a hopper in order to supply cut sheets stacked and housed in a hopper constituting the paper feeder to a printing mechanism of the printer. .

However, in the case of multi-sheet paper made by laminating a large number of carbonless papers with only the peeling roller, the upper and lower sheets are displaced and curved until the leading end reaches the printing mechanism, so that the paper can be fed smoothly. Absent. Further, in the case of paper having a short length such as a postcard, there is a problem that the paper separates from the peeling roller before its leading end reaches the printing mechanism, and the paper cannot be sent out.

In view of this, a main feed roller and a sub feed roller that rotates following by frictional contact with the main feed roller are provided between the peeling roller and the printing mechanism of the printer. A proposal was made to prevent the removal when sending. In this apparatus, each sheet is sent to the printing mechanism by always rotating each roller regardless of the length of the sheet.

[Problems to be Solved by the Invention] However, since the upstream peeling roller and the downstream main and sub feed rollers are driven by one motor,
There is a problem that a large load is constantly applied and the life is shortened.

The present invention has been made in view of the fact that the load applied to the motor is large for driving the peeling roller. The present invention prevents the paper from being bent when the paper is fed, and makes the paper smooth regardless of the length of the paper. It is an object of the present invention to provide a paper feeder capable of reducing the load applied to a motor while being able to feed the paper.

[Means for Solving the Problems] In order to achieve the above object, the present invention provides a separation roller for separating the topmost one of stacked and stored single-sheet paper from another paper and feeding the separated paper in the paper feeding direction. A platen arranged opposite a print head for printing on the cut sheet sent by the peeling roller, and a cutout sent from the peeling roller, arranged between the peeling roller and the platen. A feed roller that feeds paper toward the platen, a motor that can rotate forward and reverse, and when the motor rotates in the forward direction, the power is transmitted to the peel roller and the feed roller to move the peel roller and the feed roller in the paper feed direction. When the motor rotates in the reverse direction, the power is transmitted to the feed roller to rotate the feed roller in the paper feed direction and the peel roller. A power transmission mechanism that shuts off power to the motor, the motor is rotated in the reverse direction by the forward rotation of the motor while the leading edge of the sheet is conveyed to a position where it reaches the feed roller and does not reach the platen. Paper feeder.

[Operation] When the motor rotates in the forward direction, the power is transmitted to the peeling roller and the feed roller by the power transmission mechanism, and the peeling roller and the feed roller are rotated in the paper feeding direction. As a result, the topmost one of the stacked sheet papers is separated from the other sheets, and the leading end of the sheet is
The sheet is conveyed to a position where it reaches the feed roller and does not reach the platen.

Then, the motor is rotated in the reverse direction. At this time, the power of the motor is transmitted only to the feed roller by the power transmission mechanism, and the feed roller is rotated in the sheet feeding direction. Thereby, the cut sheet is sent out to the platen.

Embodiment An embodiment in which the present invention is embodied in a printer will be described below with reference to the drawings.

As shown in FIG. 4, a platen 2 is rotatably supported on a printer frame 1 (only part of which is shown).
On the outer periphery of the platen 2, a plurality (two) of paper press rollers 5 and a platen 2 that rotate following the rotation of the platen 2
Is provided with a paper veil 8 which can be approached and separated from the vehicle. A carriage (not shown) movable along the platen 2 is provided with a print head 6 and a platen 2.
A detachable ribbon cassette 7 accommodating a print ribbon that can travel along the line.

Above the platen 2, a paper supply / discharge device 21 is detachably mounted. That is, the frame 22 of the sheet feeding / discharging device 21 includes a pair of left and right side frames 22A and a front wall plate 22B provided between the left and right side frames. On the side frame 22A of the frame 22, a pair of connection arms 23 (only one is shown) that can be engaged and disengaged from both ends of the shaft portion 2a of the platen 2 are protruded. Also, both connecting arms 23
A pair of paper guides 23a and 23b are provided at a predetermined interval therebetween.

A hopper 25 for accommodating the cut sheets 3 in a stacked state is mounted on the frame 22 in an inclined state in which the upper surface thereof is inclined rearward of the printer. The frame 22 has a hopper
A separation roller 26, which separates the uppermost cut-sheet paper 3 on the other paper 25 from other paper and then sends it out to the platen 2, as well as a main feed roller 27 and a sub-feed roller 28, via their shaft portions 26a, 27a, 28a. Each is rotatably supported. Main feed roller
27 and the sub-feed roller 28 are in contact with each other, and the cut sheet 3 is sent out between the rollers 27 and 28.

A stacker 30 shown in FIG. 4 is mounted on the frame 22. The stacker 30 is open in both upper and lower surfaces and has a box shape elongated in a direction parallel to the platen 2. A lower support portion 31 for supporting the lower end of the cut sheet 3 discharged from the platen 2 is provided at the lower front inside the stacker 30.

A support piece 3 for supporting the upper portion of the cut sheet 3 with the printing surface facing the printer frame 1 is provided on the support portion 31 so that the upper end of the support piece 3 is inclined forward of the printer. .

The rear wall of the stacker 30 is formed as a guide wall 35, and inside the guide wall 35, an unloading roller 36 for sending the cut sheet 3 sent from the platen 2 toward the support piece 33. Is rotatably supported via the shaft portion 36a, and a flexible film 34 for pressing the cut-sheet paper 3 toward the discharge roller 36 is provided.

Next, a driving mechanism for driving each roller will be described.

As shown in FIG. 1 and FIG.
On the outer surface of the A, the peeling roller 26, the main feed roller 27,
On each shaft portion 26a, 27a, 36a of the unloading roller 36, a peeling gear 18,
The main feed gear 40 and the carry-out gear 43 are mounted so as to be integrally rotatable. On the other hand, on one side of the peeling gear 18, a drive motor M that rotates in response to an electric pulse is provided on the outer surface of the outer frame 22A. The motor gear 11 provided at the motor shaft end of the drive motor M meshes with a large-diameter gear of a reduction gear 12 in which two gears having different radii are formed so as to be able to rotate integrally. On the other hand, a power transmission gear 14 is rotatably supported in the vicinity of the reduction gear 12, and the rotation of the reduction gear 12 is transmitted through the small-diameter gear and the idle gear 13.
Is transmitted to

A swing arm 15 is swingably mounted at an intermediate portion on a rotation center shaft 14a protruding integrally with the power transmission gear 14. The swing arm 15 is frictionally coupled so as to swing integrally with the rotation center shaft 14a, and slippage occurs with the rotation center shaft 14a when the swing arm 15 stops. A main oscillating gear 16 and a sub oscillating gear 17 are rotatably attached to both ends of the oscillating arm 15, respectively, and both the main and sub oscillating gears 16 and 17 are meshed with the power transmission gear.

A pair of large and small idle gears 19 and 20 for transmitting the rotation of the sub oscillating gear 17 to the main feed gear 40 are rotatably supported between the sub oscillating gear 17 and the main feed gear 40.

Then, as shown in FIGS. 1 and 3, the main swing gear
The gear 16 is selectively engaged with the peeling gear 18 or the large-diameter idle gear 19 in accordance with the swing of the swing arm 15. On the other hand, the sub oscillating gear 17 is removably meshed with the idle gear 20 in accordance with the swing of the oscillating arm 15. At the same time, when the main swing gear 16 is engaged with the idle gear 19, the main swing gear 16 is separated from the idle gear 20. Accordingly, the idle gear 19 is always drivingly connected to the power transmission gear 14 via the main swing gear 16 or via the auxiliary swing gear 17 and the idle gear 20.

An idle gear 41 meshing with the main feed gear 40 is provided on the side frame 22A between the main feed gear 40 and the output gear 43, and the output gear 43 is provided on the outer frame of the stacker 30. An idle gear 42 that meshes is provided, and both idle gears 41 and 42 are meshed.

The operation and effect of the paper feeder of the printer configured as described above will be described with reference to the drive characteristic diagram of the drive motor shown in FIG.

As shown in FIG. 4, in a state in which the cut sheet 3 is stacked on the hopper 25, the drive motor M is rotated forward for 30 pulses at 100 pps (pulses / second), and then 390 at 270 pps.
Rotate forward by the number of pulses. With this rotation, when the motor gear 11 is rotated in the forward direction (the direction of the arrow in FIG. 1), the power transmission gear 14 is rotated in the counterclockwise direction via the reduction gear 12 and the idle gear 13. As the rotation center shaft 14a of the power transmission gear 14 rotates, the swing arm 15 also swings in the same direction due to frictional contact, and the main swing gear 16 meshes with the separation gear 18. Accordingly, the peeling roller 26 is rotated and the hopper
The uppermost sheet in the cut sheet 3 stacked on the sheet 25 is separated from the lower sheet, and fed between the main feed roller 27 and the sub feed roller 28.

On the other hand, the sub-oscillating gear 17 meshes with the idle gear 20 by the counterclockwise rotation of the oscillating arm 15, so that the rotation of the auxiliary oscillating gear 17 is mainly transmitted through the idle gear 20 and the idle gear 19. The power is transmitted to the feed gear 40, and the main feed roller 27 is rotated integrally with the main feed gear 40 in the sheet feeding direction. Then, with the cooperation of the main feed roller 27 and the sub-feed roller 28 which rotates following the main feed roller 27, the cut sheet 3 is fixed along the paper guide 23b while being held between the main and sub-feed rollers 27, 28. Will be sent in quantity. At this time, as shown in FIG. 4, the leading end of the cut sheet 3 is located above the sheet pressing roller 5.

Next, the drive motor M is kept stopped for 20 ms (milliseconds) as shown in FIG. 8, and thereafter, is reversely rotated (in the direction of the arrow in FIG. 3) at 250 pps for 103 pulses. The rotation of the drive motor M is transmitted to the power transmission gear 14 via the motor gear 11, the reduction gear 12, and the idle gear 13, and rotates this clockwise. Accordingly, the swing arm 15 rotates clockwise, the main swing gear 16 separates from the separation gear 18, and the sub swing gear 17 separates from the idle gear 20. Then, only the main swing gear 16 meshes with the idle gear 19 to transmit rotational power.
Turn 19 clockwise. Therefore, after the cut sheet 3 is nipped between the main and sub feed rollers 27, 28, the separation roller 2
6 changes from a rotating state by the power of the driving motor M to a freely rotatable state. The sheet 3 is sent to the platen 2. Subsequently, when the drive motor M is rotated reversely for 30 pulses at 100 pps, as shown in FIG.
And the paper pressing roller 5.

After that, the drive motor M is kept in a stopped state for 40 ms, and then is rotated in reverse by 200 pulses at 100 pps. In synchronization with the reverse rotation of the drive motor M at this time, the platen 2 which has been in a freely rotatable state until now rotates counterclockwise in FIG. Based on the reverse rotation and the rotation of the platen 2, the leading end of the cut sheet 3 is reliably positioned and pinched between the platen 2 and the sheet pressing roller 5. The drive motor M is driven for 400 ms until the paper bale 8 of the platen 2 is once separated from the platen 2 by an actuator (not shown).
The power supply to is stopped. On the other hand, the platen 2 is kept stopped during this time. Subsequently, simultaneously with the rotation of the platen 2 in the counterclockwise direction, the drive motor M is driven at 480 pps for 213 pulses,
It is reversed. Therefore, after the cut sheet 3 is fed to the position of the paper bale 8 by the platen 2 and the main and sub-feed rollers 27 and 28, the paper bale 8 is returned to contact the platen 2 again, and The cut sheet 3 is sandwiched between the paper veil 8. By the operation described above, the setting of the cut sheet 3 is completed, and the driving motor M
Is stopped.

Then, as shown in FIG. 6, after printing is performed on the cut sheet 3 based on the operation of the print head 6, the cut sheet 3 is transferred to the stacker 30 with the rotation of the platen 2, and It is introduced between the carry-out roller 36 and the flexible film 34 through the space between the support portion 31 and the support portion 31. When the printing of one page is completed, the leading end of the cut sheet 3 is moved out of the discharge roller 36.
And the flexible film 34, the drive motor M is rotated again in the reverse direction. With the rotation of the main feed gear 40 based thereon, the carry-out roller 36 is rotated via the idle gears 41 and 42 and the carry-out gear 43, and the printed cut-sheet paper 3 is supported by the stacker 30 as shown in FIG. It is laminated on the piece 33.

As described above, according to the paper feeding device of the printer of the present embodiment, the separation roller 26 is driven to drive the cut sheet 3 from the hopper 25.
After the front end of the cut sheet 3 is inserted between the main and sub feed rollers 27 and 28, the drive motor M is rotated in the reverse direction to interrupt the transmission of power to the separation roller 26, The load on the motor M can be reduced.

The present invention is not limited to the above embodiment,
The present invention can be embodied in the following modes. That is, although the drive motor M is provided in the paper supply / discharge device 21 in the above embodiment, it may be provided in a printer, and may also serve as a motor for rotating and driving the platen 2.

[Effects of the Invention] According to the present invention, it is possible to prevent the sheet from being bent at the time of feeding the sheet,
Since the paper can be smoothly fed regardless of the length of the paper, and the peeling roller and the downstream-side feed roller, the peeling roller having a large load at the time of driving can be driven only when necessary, so the motor This has an excellent effect that the load applied to the substrate can be reduced.

[Brief description of the drawings]

1 to 8 show an embodiment of a printer embodying the present invention, FIG. 1 is a side view showing a drive mechanism, FIG. 2 is a plan view of the same, and FIG. Side view,
FIG. 4 is a side sectional view of the printer, FIGS. 5 to 7 are explanatory views of the paper position in paper feeding, FIG. 5 is a view showing a state in which the leading edge of the paper has been moved between a platen and a paper pressing roller, FIG. 6 is a diagram showing a printing state of a sheet, FIG. 7 is a diagram showing a state in which the sheet is fed onto a stacker by an unloading roller, and FIG. 8 is a schematic diagram showing driving characteristics of a driving motor. 2 ... platen, 3 ... cut paper, 6 ... print head,
14 to 17: a power transmission gear, a rocking arm, a main rocking gear, and a sub rocking gear, which constitute a power transmission mechanism;
27: a main feed roller as a feed roller; 28: a sub feed roller as a feed roller; M: a drive motor.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) B41J 13/00 B41J 13/02

Claims (1)

(57) [Claims] 1. A peeling roller for peeling off the uppermost one of the stacked sheet papers from another sheet and sending out the paper sheet in a paper feed direction, and printing on the cut sheet paper sent out by the peeling roller. A platen arranged to face a print head for performing the operation, a feed roller arranged between the peeling roller and the platen, and for feeding cut-sheet paper sent from the peeling roller toward the platen; A reversible motor, when the motor rotates in the forward direction, the power is transmitted to the peeling roller and the feed roller to rotate the peeling roller and the feed roller in the paper feeding direction, and when the motor rotates in the reverse direction, the feed is performed. A power transmission mechanism that transmits the power to the roller to rotate the feed roller in the paper feed direction and shuts off the power to the peeling roller; Data, set its by forward rotation, sheet feeding apparatus characterized by being reverse rotation in a state of being transported to a position where the leading edge of the paper does not reach the reached and the platen to the feed roller.