JPH0523343Y2 - - Google Patents

Description

[Detailed explanation of the idea] [Industrial application field]

The present invention relates to a paper feed mechanism for conveying continuous printing paper in printers such as dot printers and serial printers, and more particularly to a paper feed mechanism for printers that facilitates the insertion and setting of paper and prevents paper jams.

[Conventional technology]

As shown in FIG. 1, the paper feed mechanism of a conventional printer has a conveyance path for continuous paper 5, which includes a push-in pin tractor 2, a paper guide 3, and an overfeed roller 4 around a platen 1. , continuous paper 5 fed out in the direction of arrow A by the pin tractor 2
is guided by the paper guide 3 to the platen 1.
and the printing head 6, and the overfeed roller 4
The rotation of the platen 1 and the platen 1 causes the platen 1 to be sent in the direction of arrow B. In FIG. 1, reference numeral 7 is a scale indicating the printing position of characters, etc. In order to set the continuous paper 5 in such a paper feeding mechanism, the continuous paper 5 is inserted into the gap between the overfeed roller 4 and the outer peripheral surface of the platen 1 and advanced.
Thereafter, the overfeed roller 4 is rotated and lifted up to the position C in FIG. The overfeed roller 4 is inserted into the gap between a certain overfeed roller 4 and the outer peripheral surface of the platen 1, and then the overfeed roller 4 is moved to the first overfeed roller 4.
It was set between the overfeed roller 4 and the platen 1 by rotating and lowering it to the original position shown in the figure.

[Problem that the idea aims to solve]

However, in this case, the operator must hold the leading end of the continuous paper 5 by hand each time and insert it into the gap between the lifted overfeed roller 4 and the platen 1, which makes the insertion and setting process cumbersome. Ta. Furthermore, since the continuous paper 5 is wound around the outer peripheral surface of the platen 1 over approximately 1/2 of the circumference, the contact area between the continuous paper 5 and the platen 1 increases, and the diameter of the platen 1 increases. The platen is easily affected by changes in expansion and contraction and frictional force, and paper jams are likely to occur. Furthermore, in the case of continuous paper 5 that has a perforation in the middle and folds into a bellows shape, the continuous paper 5 may swell outward at the perforation near the front of the overfeed roller 4. This resulted in uneven spacing between printed lines, resulting in poor line feed accuracy. The present invention has been made to solve the above-mentioned problems, and it is an object of the present invention to provide a paper feed mechanism for a printer that facilitates the insertion and setting of paper and prevents paper jams.

[Means to solve the problem]

According to the present invention, the above purpose is achieved by installing a push-in pin tractor 2 around the platen 1, as shown in FIG.
, a paper guide 8 that guides the continuous paper 5 sent out by the pin tractor 2 to a position facing the print head 13 of the platen 1; and a paper guide 8 that rotates in contact with the outer peripheral surface of the platen 1 to a position facing the print head 13. and a paper pressing roller 9 that presses the continuous paper 5 that has passed through the platen 1.
and the printing head 13 facing the platen 1 so as to rise substantially vertically, and the paper presser roller 9 is moved between a closed position where it rotates in contact with the platen 1 and a position where it is in contact with the platen 1. when the contact state is released and above the print head 13,
The continuous paper 5 can be moved between an open position where it is deviated toward the print head 13 side from the upward extension line of the conveyance path 10 at the opposing position between the platen 1 and the print head 13, and does not interfere with the extension line. The paper press roller 9 is mechanically fixed in the closed position, and when the paper press roller 9 is moved from the closed position to the open position, the paper press roller 9 is moved. An operating lever 17 having a latch 20 that releases the mechanical fixation of the paper press roller 9 in conjunction with the paper press roller 9 is connected, and a paper cutter that opens and closes together with the paper press roller 9 is provided near the paper press roller 9. This is achieved by providing a paper feeding mechanism characterized in that it is provided with 11.

[Effect]

In the present invention, the continuous paper 5 pushed out by the push-type pin tractor 2 is guided by a paper guide 8 and transported on a transport path 10 that includes a position where a print head 13 and a platen 1 face each other. The paper guide 8 is connected to the print head 13 and the platen 1.
Continuous paper 5 rises almost vertically in a position opposite to
This reduces the contact area with the platen 1 and reduces the effects of expansion and contraction of the platen 1, changes in frictional force, etc. Further, the paper press roller 9 that presses the continuous paper 5 against the platen 1 can be moved between a closed position where the continuous paper 5 is pressed against the platen 1 during printing operation and an open position where it is separated from the platen 1 by operating the operation lever 17. can be moved and in the open position,
The continuous paper 5 is retracted to a position deviated toward the printing head 13 from the upward extension line of the conveyance path at the opposing position between the platen 1 and the printing head 13, and the continuous paper 5 is moved upward from the opposing position between the platen 1 and the printing head 13. Interference with the continuous paper 5 being conveyed is prevented. Under such a configuration, the continuous paper 5 is operated by the operation lever 17.
The continuous paper 5 can be set by simply operating the operating lever 17 in the opening direction to feed out the continuous paper 5, and then operating the operating lever 17 in the closing direction, and the paper pressing roller 9 is retracted to a position where it does not interfere with the continuous paper 5. The continuous paper 5 is reliably prevented from being drawn into the presser roller 9 side.

【Example】

Embodiments of the present invention will be described in detail below with reference to the accompanying drawings. FIG. 2 is an explanatory side view showing the paper feeding mechanism of the printer according to the present invention. Around the platen 1, there is a push-in pin tractor 2 and a paper guide 8.
A conveying path 10 for the continuous paper 5 is formed by the outer circumferential surface of the platen 1 and the paper pressing roller 9 that rotates in contact with the outer circumferential surface of the platen 1. A paper cutter 11 is provided near the paper presser roller 9 and also serves as a scale for indicating the printing position of characters and the like. In FIG. 1, reference numeral 12 is a print mask provided between the platen 1 and the print head 13. Here, in the present invention, the paper guide 8
is combined with an upper guide 8u and a lower guide 8l with a space between them that allows the continuous paper 5 to pass through. This paper guide 8 allows the continuous paper 5 guided by it to rise approximately vertically between the platen 1 and the printing head 13 facing it, and as shown in FIG. It slopes downward from the rear end of the tractor 2 as a starting point, bulges downward below the platen 1, and ends at the print mask 12 on the front side of the platen 1, that is, on the printing head 13 side. It is formed in a substantially semicircular arc shape. Further, the paper presser roller 9 rotates in the directions of arrows C and E in FIG. 2 and moves between a closed position in which it contacts the platen 1 and an open position in which the contact state with the platen 1 is released. It is considered possible. That is, plates 16, 16 (this plate 16 is shown in FIG. The paper cutter 11 is provided on both sides of the platen 1, and is pivoted on the lower surface of a paper cutter 11 which also serves as a scale. The open position of the paper presser roller 9 is set at a position offset toward the print head 13 from the upward extension of the transport path of the continuous paper 5 at the opposing position between the platen 1 and the print head 13. When the presser roller 9 is in the open position, the paper presser roller 9 is prevented from interfering with the continuous paper 5 that has been conveyed substantially vertically upward from the position where the platen 1 and the print head 13 face each other. Therefore, the mounting arm 15 is shown by arrows F and G.
When the paper presser roller 9 rotates in the
also rotates in the directions of arrows D and E. When the paper press roller 9 rotates in the direction of arrow D, that is, in the open position, the paper guide 8 guides the platen 1 and the print head 1 facing it.
3, and the continuous paper 5 moves up between the platen 1 and the print head 13 as it is. Further, an operating lever 17 is provided at the upper end of the mounting arm 15.
By rotating 7 in the directions of arrows H and I, the paper pressing roller 9 is opened and closed, and is fixed in the closed position. That is, the mounting base 18 of the operating lever 17 is pivotably supported by the pivot 19 of the mounting arm 15, and the rear end surface can come into contact with the rear wall of the mounting arm 15 during rotation, and A latch 20 at the tip of the mounting base 18 is removably engaged with a stopper piece 21 erected on the front side of the platen 1 body. A spring 23 is tensioned between the vicinity of the latch 20 and the mounting arm base 22, and the contracting force of the spring 23 engages and fixes the latch 20 of the operating lever 17 and the stopper 21. A toggle spring 25 is interposed between the right end of the mounting arm base 22 in FIG. 2 and a stop shaft 24 implanted at a predetermined position on the main body. The mounting arm 15 is urged in the direction of arrow G. Then, as shown in FIG.
7 to open the paper pressing roller 9, the stopper portion 26 formed at the upper right side of the mounting arm base 22 comes into contact with the stop shaft 24 and is fixed in the open position. Therefore, the paper pressing roller 9 is moved to the platen 1.
In order to open the
7 in the direction of arrow H. At this time, as shown in FIG.
9, the rear end surface of the mounting base 18 comes into contact with the rear wall of the mounting arm 15, and at the same time, the latch 20 at the tip end and the stopper piece 21 are disengaged. Once the fixation at the closed position is released in this way, if a force is further applied in the direction of arrow H, the rear end surface of the mounting base 18 will press the mounting arm 15 and rotate the entire mounting arm 15 in the direction of arrow F. move. Then, toggle spring 2
5, the mounting arm 15 is rotated about the support shaft 14 in the direction of arrow F, and as shown in FIG. 4, the stopper portion 26 of the mounting arm base 22 comes into contact with the stop shaft 24 and stops. do. As a result, the paper press roller 9 and the paper cutter 11 are fixed in the open position. In this state, the continuous paper 5 guided approximately perpendicularly by the paper guide 8 at the opposing portion of the platen 1 and the print head 13 moves onto the platen 1 without interfering with the paper presser roller 9.
and the paper pressing roller 9. Next, in order to close the paper pressing roller 9 with respect to the platen 1, the operating lever 17, which is in the H position in FIG. 4, is rotated in the direction of the arrow I. At this time,
The upper part of the mounting base 18 of the operating lever 17 comes into contact with the upper wall of the mounting arm 15, and the mounting arm 15 is rotated in the direction of arrow G. And the mounting base 18
When the latch 20 reaches the upper end of the stopper piece 21, the tapered portion of the front part of the latch 20 climbs over the stopper piece 21, and the stopper piece 21
and the latch 20 are engaged and fixed by the contraction force of the spring 23. As a result, the paper pressing roller 9 presses the continuous paper 5 inserted between the platen 1 and the platen 1 onto the outer peripheral surface of the platen 1 and is closed, completing the setting of the continuous paper 5. At this time, the paper cutter 11 is also fixed in the closed position together with the paper press roller 9.

[Effect of the idea]

Since the present invention is configured as described above, when inserting and setting continuous paper, the operator does not have to pinch the leading end of the continuous paper each time to insert it, and simply operates the operating lever in the opening direction to insert the continuous paper into the platen. The paper can be set simply by feeding out the continuous paper to the front side of the machine and then operating the operating lever in the closing direction. Therefore, the continuous paper can be inserted and set extremely easily. In addition, since the continuous paper is guided by the paper guide and rises almost vertically between the platen and the print head facing it, the contact area with the platen is reduced, and the expansion and contraction of the platen and the frictional force are reduced. It is less affected by changes, etc., and paper jams can be prevented. Further, the presser roller is retracted to a position deviated toward the print head from an upward extension of the conveyance path at a position facing the platen and the print head, and the presser roller is moved toward the print head side from the upward extension line of the conveyance path at the opposite position between the platen and the print head. Since interference is prevented, the continuous paper is reliably prevented from being drawn into the presser roller side, and the reliability of the insertion and setting operation can be improved. Furthermore, since the continuous paper rises almost vertically in the area facing the platen and print head, even if the continuous paper is perforated in the middle and folded into a bellows shape, the paper presser will not work. Continuous paper does not bulge outward near the front of the rollers.
The line spacing between prints becomes uniform, and line feed accuracy can be prevented from deteriorating. In addition, since the paper press roller is fixed with a latch, the paper press roller will not lift up even when using thick continuous paper, making it possible to achieve stable feeding of continuous paper. The upper presser roller can be locked and unlocked simply by the operation of , which improves operability and further simplifies the overall structure.

[Brief explanation of drawings]

Fig. 1 is an explanatory side view showing a paper feeding mechanism of a conventional printer, Fig. 2 is an explanatory side view showing a paper feeding mechanism of a printer according to the present invention, Fig. 3 is a plan view thereof, and Fig. 4 shows its operating state. FIG. 1...Platen, 2...Pin tractor, 5...
Continuous paper, 8... Paper guide, 9... Paper press roller, 10... Conveyance path, 11... Paper cutter,
13...Print head, 17...Operation lever, 20
...Ratsuchi.

Claims (1)

[Claims for Utility Model Registration] A push-in pin tractor is placed around the platen,
A paper guide that guides the continuous paper sent out by the pin tractor to a position facing the print head of the platen, and a paper guide that rotates in contact with the outer peripheral surface of the platen and presses the continuous paper that has passed the position facing the print head against the platen. the paper guide is formed so that the continuous paper rises substantially vertically between the platen and the print head facing the platen, and the paper press roller is in contact with the platen. Printing is performed from an upward extension of the conveyance path at a position where the continuous paper platen and the print head are opposed to each other, and the contact state with the platen is released, and the print head is located above the print head and faces the platen of the continuous paper and the print head. The paper presser roller is formed to be movable between an open position that is deviated toward the head side and does not interfere with the extension line, and the paper presser roller is mechanically fixed in the closed position, and the paper presser roller is mechanically fixed in the closed position. When moving the rollers from the closed position to the open position,
An operating lever equipped with a latch that releases the mechanical fixation of the paper presser roller in conjunction with the movement of the paper presser roller is connected, and a sheet of paper that opens and closes together with the paper presser roller is connected near the paper presser roller. A paper feed mechanism characterized by a cutter.