JPH0615249B2 - Printer - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printer for an electronic computer, which feeds a sheet by a feed roller mechanism for pinching and feeding the sheet with a pair of opposed rollers. The present invention relates to a structure of a printer provided with a tractor for sending and capable of performing both print processing on cut sheets and continuous forms sheets.

-Summary of the Invention-The apparatus of the present invention is a printer capable of feeding single-cut sheets and pulling and feeding continuous form sheets, and is capable of feeding continuous form sheets by switching the rotation direction of a tractor for feeding continuous form sheets. It is possible to perform printing processing by pulling and feeding by pulling and feeding by pushing feeding, and the rollers of the feed roller mechanism for feeding single-cut sheets can be contacted and separated from each other and the contact force can be converted into two levels of strength and weakness. , Feeding single-cut sheets with a strong feed force between the rollers and the feed roller mechanism alone, and feeding paper with a tractor by separating the rollers from each other, and feed roller mechanism The tractor and the tractor are synchronously rotated in the opposite directions, and the tractor and the feed roller mechanism, which holds the paper lightly, cooperate with the tractor to enable the accurate and stable pushing and feeding of the continuous form paper. Furthermore, when the end of the paper passes through the tractor at the time of pushing and feeding the continuous paper, the paper holding force of the feed roller mechanism is changed from weak to strong, so that the end of the paper can be fed accurately and stably at the time of pushing and feeding. It is possible to send.

-Prior Art-Fig. 7 shows a structural example of a printer which is a prior art of the present invention. In the figure, 1 is a platen, 2 is a print head,
A print area P is formed between them. Reference numerals 3 and 4 denote feed roller mechanisms for single-sheet feeding, which are arranged close to both sides of the print area P.
a and a pair of driven rollers 3b and 4b,
The driven rollers 3b and 4b can come into contact with and separate from the drive rollers 3a and 4a. Reference numeral 50 is an automatic sheet feeder for single-cut sheets, 51 is a manual sheet feeder, and 52 is a guide plate for guiding the sheet fed from the automatic sheet feeder 50 to the feed roller mechanism 3 on the right side in the drawing. 53 is a stacker, and 5 is a tractor.
The lower back plate 55 and the bottom plate 56 are divided into the lower back plate 55 and
Is rotated about the axis shown by 57 in the figure and positioned at the position of the imaginary line, so that the tractor 5 can be fed at the time of feeding continuous paper.
The lower back plate 55 guides the sheet between the sheet and the feed roller mechanism 4 on the left side of the drawing.

The single-cut sheets supplied from the manual paper feed tray 51 or the automatic paper feeder 50 are sandwiched between the rollers of the feed roller mechanisms 3 and 4 and fed, and after being printed, discharged to the stacker 53. To be done. For continuous paper, use the manual paper feed tray 51.
Of the feed roller mechanisms 3 and 4 and the driven rollers 3b and 4b of the feed roller mechanisms 3 and 4 are separated from the drive rollers 3a and 4a, and are fed by being pulled by the tractor 5 to the rear of the printer (left side in the figure). Is discharged. That is, in the conventional printer having the structure shown in FIG. 7, the continuous form paper is fed by pulling it with the tractor 5.

-Problems to be solved by the invention-For continuous form paper, the feeding accuracy is more stable by pulling and feeding, but the continuous form paper must be removed from the tractor 5 each time when performing printing processing of cut sheets. The complication that it does not happen occurs. Therefore, there is a demand for pushing the continuous form paper and feeding it. However, when the continuous form paper is pushed in and fed by a printer as shown in FIG. 7, the feeding becomes extremely unstable, and stable and accurate printing processing is performed. There was a problem that you can not do.

Therefore, the present invention is directed to a printer capable of performing printing processing by feeding cut sheets and pulling and feeding continuous form sheets,
Further, it is an object of the present invention to provide a printer capable of stably and accurately performing printing processing of continuous paper by pushing and feeding.

-Means for Solving Problems-In the printer of the present invention, in the printer in which the feed roller mechanisms 3 and 4 are arranged in the vicinity of the print area P and the tractor 5 is arranged on one side of the print area P, 5
And the feed roller mechanisms 3 and 4 are provided so as to be switchable in the rotational direction, and by switching between these, the printing process by pushing and feeding the continuous form paper and the printing process by pulling and feeding are performed, and at least the continuous form paper is pushed and fed. At the time of feeding, the tractor 5 and the feeding roller mechanisms 3 and 4 are synchronously rotated.

The rollers 3b and 4b of the feed roller mechanisms 3 and 4 can be brought into contact with and separated from the opposing rollers 3a and 4a, and the abutting force can be converted into two levels of strength and weakness. Change to weak when pushing and feeding the book paper,
The above-mentioned rollers are separated from each other when the continuous form paper is pulled and fed.

Further, when the continuous paper sheet is pushed in and fed, in which the contact force of the feed roller mechanisms 3 and 4 is weak, when the end of the continuous paper sheet is separated from the tractor 5, the contact force of the feed roller mechanisms 3 and 4 is reduced. It transforms from weak to strong.

-Operation- In the printer having the above-mentioned configuration, the single-cut sheet is only pressed by the friction driving force of the feed roller mechanisms 3 and 4 in a state in which the rollers 3a and 3b, 4a and 4b facing each other are strongly pressed to firmly sandwich the sheet. The continuous paper fed and pulled and fed is fed only by the pin feed of the tractor 5 with the rollers 3a and 3b, 4a and 4b separated from each other. These are similar to the feeding in the conventional printer. Then, the continuous form paper by pushing and feeding is in the opposite direction to the case of pulling and feeding by pulling the tractor 5 and the feed roller mechanisms 3 and 4 in a state in which the rollers of the feed rollers 3 and 4 are weakly pressed and the paper is lightly sandwiched. The paper is fed after being rotated synchronously with. At this time, the feed force is applied to the push-in continuous form paper from the feed roller mechanisms 3 and 4 close to the print area, so that the paper does not bend or bend between the tractor 5 and the print area P. Moreover, since the feed force applied from the feed roller mechanisms 3 and 4 is weak, the line feed accuracy and the like are regulated by the rotation of the tractor 5, so that stable and accurate push-feeding can be performed.

Further, when the continuous form paper is pushed and fed in this way, if the pressure applied to the feed rollers 3 and 4 is increased when the trailing end of the paper is separated from the tractor 5, the feed rollers 3 and 4 are strengthened. Since the continuous form paper is continuously fed by the clamping force, the pushed continuous form paper can be reliably fed to the end.

-Embodiment- Next, a drawing showing an embodiment in which the present invention is applied to the printer of FIG. 7 will be described. FIG. 1 is a side view showing the main part of the printer, FIGS. 2 and 3 are side views showing the operation of the pressure mechanism of the feed roller, and FIG. 4 is a diagram showing the tractor drive system linked with the pressure mechanism. FIG. 5 is a perspective view showing a mechanism for removing the mechanism, FIG. 5 is a flow chart showing a control procedure, and FIG. 6 is a flow chart showing a feeding control procedure for the push-in continuous form paper. In the figure, those explained with reference to FIG. 7 are assigned the same reference numerals as in FIG. Reference numeral 6 denotes a sensor provided at the position of the tractor 5 for detecting the sheet end.

The drive rollers 3a and 4a of the feed roller mechanism are pivotally supported in a non-moving position by a frame (not shown). Although not shown in the drawing, the platen 1 and the driving rollers 3a and 4a are linked by a timing belt at the end opposite to the end shown in FIG. 1, and are synchronously driven by a pulse motor rotating in the forward and reverse directions. It has a structure that

Reference numeral 8 denotes a control shaft that is axially supported immediately below the platen 1, and a cam 9 is fixed to one end of the control shaft. Cam 9
Has a two-stepped projecting portion 91, 92 on its outer circumference and also has an outwardly extending arm 94 provided with an inclined surface 93.

The driven rollers 3b and 4b of the feed roller are pivotally attached to the tips of arms 12 and 13 fixed to support shafts 10 and 11 which are mounted in a stationary position. First links 14 and 15 extending downward are fixed to the support shafts 10 and 11, and forks 141 and 151 are formed at the lower ends thereof. 1st link 1
Below the pins 4 and 15, L-shaped second links 18 and 19 are provided so as to be swingable around the pins 16 and 17 in the non-moving position. Cam followers 181 and 191 facing the cam 9 are formed at one ends of the second links 18 and 19, and the pin 1 is provided at the other ends.
82, 192 are planted and the pins 182, 192 are first
The forks 141 and 151 of the link are engaged with each other with a large play gap. Numerals 20 and 21 are tension springs mounted between the second links 18 and 19 and a frame (not shown).

A pinion 30 is fixed to the shaft of the rear drive roller 4a, and the rotation of the drive roller 4a is transmitted to the tractor 5 via the intermediate gear 31, the pinion 32, and the timing belt 33. As shown in FIG. 4, the intermediate gear 31 is slidably and rotatably mounted on the fixed shaft 34.
By moving the intermediate gear 31 in its axial direction, the pinion 30 and the intermediate gear 31 are disengaged from each other, and the tractor 5
The structure is such that the feed rollers 3 and 4 and the platen 1 can be rotated without rotating. The inclined surface 93 of the arm 94 provided on the cam 9 serves as an operation source for moving the intermediate gear 31, and when the intermediate gear 31 is pushed toward the inclined surface 93 and the inclined surface 93 moves backward. A compression spring 35 is provided for returning the intermediate gear 31 to the position where it meshes with the pinion 30.

The control shaft 8 is rotationally controlled by a pulse motor (not shown), and the state shown in FIG.
1, 191 are separated from the peripheral surface of the cam 9 and the driven roller 3
b and 4b are driven by the springs 20 and 21 to drive rollers 3a,
It is strongly pressed by 4a, and the intermediate gear 31 is moved by the pushing motion of the inclined surface 93 of the arm 94 extending from the cam 9 so that the linkage with the pinion 30 is cut and the tractor 5 is not driven.

Next, the operation of the printer having the above configuration will be described with reference to the flowchart of FIG.

When the printing process is instructed, the control asks in step 60 the type of paper used. When the single-cut processing is instructed, the control shaft 8 is rotated in step 61 to set the apparatus in the state shown in FIG. 1, and steps 62 and 64 are repeated to feed roller mechanisms 3, 4 and Printing is performed while the platen 1 is rotated in the forward direction to feed the paper. At this time, the feed roller mechanisms 3 and 4 firmly hold the paper, and the tractor 5 does not rotate.

If continuous form paper is ordered in step 60,
In step 65, the control further asks for the difference between push-feeding and pull-feeding. When the pulling and feeding instruction is given here, in step 66, the control shaft 8 rotates the cam 9 to the position shown in FIG. In this state, the pushing motion of the intermediate gear 31 by the inclined surface 93 is released, and the intermediate gear 31 and the pinion 3
0 meshes with each other, and the cam followers 181 and 191 ride on the higher protruding portion 92 of the cam 9 and swing the links 18, 19 and 14, 15 to separate the driven rollers 3b and 4b from the drive rollers 3a and 4a. Step 62 in this state
Through 64 are repeated, the platen 1, the feed roller mechanisms 3 and 4, and the tractor 5 are rotated in the forward direction to feed the sheet and perform the printing process. At this time, since the driven rollers 3b and 4b are separated from the drive rollers 3a and 4a, the drive rollers 3a and 4a simply rotate, and all the sheet feeding force is applied from the tractor 5.

When the pushing and feeding is instructed in step 65, the control shaft 8 rotates the cam 9 to the position shown in FIG. 3 in step 67. The drive system of the tractor 5 is connected in this position in the same manner as when pulling and feeding, but the cam follower 18
Since the pins 1 and 191 are in contact with the lower protrusion 91 of the cam 9, the pins 182 and 1 of the second links 18 and 19 are in contact with each other.
92 is the forks 141 and 151 of the first links 14 and 15.
And the driven rollers 3b and 4b are weakly contacted with the drive rollers 3a and 4a only by their own weight.
In this state, steps 62 to 64 are repeated, and the printing process is performed while the paper is being fed by the synchronous reverse rotation of the tractor 5 and the feed rollers 3 and 4.

During this push-in continuous book processing, the continuous paper is fed by the tractor 5 and is also weakly nipped by the feed roller mechanisms 3 and 4 in the vicinity of the printing area P, so that the feeding force is also applied from the feed roller mechanism. , Stable paper feeding is performed. Further, since the feeding force applied from the feed roller mechanisms 3 and 4 is small, the feeding accuracy is regulated by the tractor 5, and accurate feeding is performed.
Even if there is a difference in the feeding amount from Nos. 4 and 5, the marginal punch hole of the sheet is not damaged.

The printing process by pushing and feeding the continuous form paper can be performed by repeating steps 40 to 42 in the flowchart of FIG. Here, step 41 is a procedure for collating the sensor 6 to detect the presence or absence of paper. When the sensor 6 detects that the end of the sheet has passed, that is, the absence of the sheet is detected, the cam 9 is rotated from the state of FIG. 3 to the state of FIG. Increase the clamping force of. That is,
The paper feeding force that is no longer applied from the tractor 5 is compensated by strongly pinching the paper by the feed roller mechanisms 3 and 4 so that the paper can be fed accurately to the end. Steps 44 to 47 in FIG. 6 are a repeating procedure of the printing process after the feeding is transferred to the feeding roller mechanisms 3 and 4, and when the page ends in this procedure, that is, all the data to be printed is If printed, the printing process ends there. If line feed is not possible during this procedure, that is, if the number of line feeds allowed after the end of the sheet is detected by the sensor 6 has been reached and there is still data to be printed, the paper end lamp is turned on. Prompts the operator to set the paper and interrupts the printing process.

-Effects of the Invention As described above, according to the printer of the present invention, in addition to the printing process by pulling and feeding continuous form paper and the printing process on cut-sheet paper, the printing process on continuous form paper by push-feeding. It is also possible to stably and accurately feed the sheet at the time of pushing and feeding. Further, even after the end of the continuous paper fed by pushing is removed from the tractor, the feeding of the end portion of the paper can be accurately and reliably performed, and troubles due to the paper feeding failure or defect at the end portion of the paper can be avoided. be able to.

[Brief description of drawings]

1 to 6 show an embodiment of the present invention. FIG. 1 is a side view showing the main part of the printer, and FIGS. 2 and 3 show the operation of the pressure mechanism of the feed roller. FIG. 4 is a side view showing the same, FIG. 4 is a perspective view showing an engagement / disengagement mechanism of the tractor drive system that is linked to the pressure applying mechanism, and FIG. 5 is a flow chart showing a procedure for converting the pressure contact force of the feed roller mechanism depending on the type of paper. The figure is a flow chart showing the feeding control procedure of the push-in continuous form paper. FIG. 7 is a side view showing an example of the structure of a conventional printer which is the premise of the present invention. In the figure, 1: platen, 2: print head 3, 4: feed roller mechanism, 3a, 4a: drive roller 3b, 4b: driven roller, 5: tractor 6: sensor, 8: control shaft 9: cam, 91, 92: Protrusions 10, 11: Support shafts, 12, 13: Arms 14, 15: First link, 141, 151: Forks 18, 19: Second link 181,191: Cam followers 182,192: Pins, 20, 21: Tension springs

Claims (3)

[Claims] 1. Feed roller mechanisms (3), (4) for feeding single-cut sheets are provided in the vicinity of a printing area formed between a platen (1) and a print head (2). In a printer equipped with a tractor (5) for feeding continuous forms paper on one side of the printing area, the tractor (5) and the feed roller mechanisms (3), (4) are provided so that their rotation directions can be switched. By switching this, the printing process by pushing and feeding the continuous form paper and the printing process by pulling and feeding are performed, and the tractor and the feed roller mechanism can rotate synchronously at least when the continuous form paper is pushed in and fed. In addition, the feed roller mechanisms (3) and (4) are provided with a pressure mechanism capable of abutting and separating the opposing rollers from each other and converting the abutting force into two levels of strength and weakness. Strong when sending voting paper,
A printer characterized in that when the continuous form paper is pushed and fed, it is weakly switched, and when the continuous form paper is pulled and fed, the rollers are separated from each other. 2. The contact force between the rollers of the feed roller mechanisms (3) and (4) is changed from weak to strong when the trailing end of the paper passes through the tractor (5) when the continuous form paper is pushed and fed. The printer according to claim 1, characterized in that: 3. The pressure mechanism is a two-stage projecting portion (91), (92) mounted on a control shaft (8) that is driven to rotate when switching sheets.
(9) having a cam and cam followers (181), (19) of the cam.
Claim 1 or claim 1, which is constituted by a link for operatively connecting 1) and the driven rollers (3b), (4b) of the feed roller mechanism, and biasing springs (20), (21). The printer according to item 2.