JPH0512061Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a large-sized printing device, and particularly relates to a large-sized printing device that prints on large roll paper such as Japanese Industrial Standard A0 size and A1 size.

[Conventional technology] Most conventional printing devices print on relatively small print paper, so the platen, feed roller, etc. need to be small, and only one line print head is installed. Furthermore, since the top cover is small and lightweight, it is common to have only one operating member for opening and closing the top cover.

[Problem that the invention attempts to solve]

However, in the case of a large printing device that prints on large roll paper as mentioned above, the platen, line print head, etc. are also inevitably large, so depending on the arrangement of these parts, the roll paper This may make setting and line print head maintenance and inspection difficult.

In addition, in such large-scale printing devices, multiple line print heads are installed and these line print heads are driven in synchronization due to the manufacturing and cost difficulties of producing a single long line print head. It is necessary to print by doing this. However, in this case, in the case of multiple line print heads, both ends of each head are non-printing areas that cannot be printed, so in order to avoid printing omissions between these line print heads, multiple line print heads must be used. It is conceivable to arrange them in a zigzag manner by shifting their positions back and forth with respect to the sub-scanning direction, which is the feed direction of the print paper. However, in such an arrangement, it becomes necessary to shift the position of the line print head by more than the width in the sub-scanning direction, and the distance between the printing parts of each line print head becomes large. As a result, the number of steps of the feed motor for feeding paper between line print heads increases, and the influence of eccentricity of the feed roller increases, making it difficult to adjust the printing timing between line print heads, and the printing equipment A problem arises in that the entire structure becomes larger.

Furthermore, in large printing devices, the upper cover, which can be opened and closed, must be wide and heavy to accommodate large rolls of paper. It is inconvenient to open and close the top cover in one place, and it is necessary to use multiple operating members. There is also a risk of erroneous operation occurring if the device gets too hot.

Therefore, the purpose of this invention is to solve the above-mentioned problems so that large roll paper can be easily set, line print heads can be easily maintained and inspected, and the printing timing between line print heads can be improved. It becomes easier to adjust the
Furthermore, it is an object of the present invention to provide a large-sized printing device that can prevent malfunctions by detecting reliable closing of a movable lid member corresponding to an upper cover when operating a plurality of operating members.

[Means for solving problems]

In the large-scale printing apparatus of the present invention, a movable lid member is provided with an air damper to open and close freely with respect to a fixed base, and the movable lid member is movable when the movable lid member is in a closed position with respect to the fixed base. In a large printing device in which the lid member is locked to the fixed base against the opening tendency, the fixed base is provided with a paper roll storage section for storing a large roll paper and two front and rear rows of platens. In addition, the movable lid member is pivoted to the left and right fixed side plates of the fixed base so as to be swingable about a support shaft, and both ends of the movable lid member are fixed as described above against the opening tendency at the closed position of the movable lid member. Left and right operating rods are respectively provided to be locked to the base, and the movable lid member is arranged in a staggered manner with different positions and orientations in the sub-scanning direction, and the roll paper is placed in the closed position of the movable lid member. The two front and rear plates contact the front and rear two rows of platens through the
a rotatable feed roller that feeds and guides the roll paper that has passed through the front and rear two rows of platens, and a paper guide unit that detects the presence of the roll paper in the vicinity of the paper roll storage unit. An empty sensor and a tension portion protruding downward at the mounting portion between the front row line print head and the rear row line print head are provided, and the left and right rotating side plates of the movable lid member are provided. When the movable lid member is in the closed position, the movable lid member is closed by being engaged with pressing pieces formed on the left and right operating rods that lock both ends of the movable lid member. The present invention is characterized in that left and right lid open detection sensors are respectively provided to detect the opening of the lid.

[Effect]

In the large-scale printing device of the present invention, line print heads in two rows of front and rear rows can be operated by operating left and right operation levers attached around a spindle to the left and right fixed side plates of a fixed base containing two rows of front and rear platens. The provided movable lid member is opened by opening correction using an air damper, and after storing a large roll paper in the paper roll storage section in this open state, the movable lid member is released from the fixed base to open the roll paper. The setting is performed, and the left and right lid opening detection sensors provided on the left and right rotating side plates of the movable lid member, respectively, detect the closing of the movable lid member by engagement with the left and right operating members.

〔Example〕

Next, the present invention will be explained with reference to the drawings.

FIG. 1 is a perspective view showing a large-sized printing apparatus according to an embodiment of the present invention. This large-sized printing device is an enlarged copying machine, and an enlarged printing section 1 is connected to an original reading section 2 via a cable (not shown). In this large-sized printing device, for example, an A4-sized document read by a document reading section 2 is enlarged by four times vertically and horizontally by an enlarged printing section 1, and printed as an A0-sized enlarged copy.

The enlarged print section 1 has a support frame 4 with casters.
The main body is fixed base 5.
and a movable lid member 6.

A paper tray 3, which is formed by bending and welding a metal rod, is detachably attached to the horizontal rod 4a of the support frame 4 so as to hook the rear end bent portion 3a. As shown in FIGS. 13a and 13b, the front end upright portion of the paper tray 3 has a ratchet portion bent inward in a dogleg shape so as to securely capture the printed roll paper 51. It has become 3b.

As shown in FIG. 3, the fixed base 5 has a paper roll storage in the rear half position (left half position in the figure) for storing a paper roll 50 wound with a roll paper 51 made of A0 size thermal paper. A recess 5a is provided. Support plate bodies 53 are disposed at both left and right ends of the paper roll storage section 5a so that the paper roll 50 can be detachably and rotatably arranged, and are disposed at the rear and upper side of the upper end surface of the support plate body 53. A bearing recess 53a is formed by cutting out the bearing recess 53a slightly obliquely toward the front and lower side. This bearing recess 53
The central convex shaft 52a of the rim portions 52 at both ends of the paper roll 50 is fitted into the central convex shaft 52a of the paper roll 50, so that the paper roll 50 can be freely rotated by drawing out the roll paper 51, and the central convex shaft 52a can be easily removed from the bearing recess 53a. The role is to prevent this from happening.

Further, platen rollers 10a to 10 are located at the front half position of the fixed base 5 (right half position in the figure).
d, dummy platens 11a to 11d, a rotary cutter 7, etc. are provided.

As shown in FIG. 2, the platen rollers 10a to 10d and the dummy platens 11a to 11d are
Front row platen roller 10a, dummy platen 1
1b, platen roller 10c, and dummy platen 11d, and a rear row of dummy platen 11a, platen roller 10b, dummy platen 11c, and platen roller 10d.

For example, as shown in FIG. 6, the dummy platens 11b and 11d in the front row are formed of plates having a U-shaped cross section, and are screwed onto a platen pedestal 18 (see FIG. 3) fixed to the fixed base 5. The rear surface (the front side in FIG. 6) is fixed to the support member 14 fixed to the support member 14 by screws. Further, the front row platen rollers 10a and 10c are formed in the shape of rollers from an elastic body such as rubber, and have the rotating shaft 12 inserted therethrough.
Both ends of the rotating shaft 12 are inserted into the bearing member 13, and the bearing member 13 is fitted onto the support member 14 and is prevented from coming out by the dummy platens 11b and 11d or the fixing member 16 narrower than the dummy platens 11b and 11d. has been done. Note that the rear row dummy platens 11a and 11c and the rear row platen rollers 10b and 10d are similarly formed and arranged in the same manner.

Originally, it is desirable for the platen roller to receive the pressing force of a plurality of line thermal heads 20a to 20d arranged in a staggered manner with one large platen roller. Thermal head 20a
Eccentricity is likely to occur from a pressing force of ~20 d, and extremely high precision is required, which is difficult to realize. It is also conceivable to use one fixed platen for the plurality of line thermal heads 20a to 20d arranged in a staggered manner, but in this case, the line thermal heads 20a to 20d
Because a large frictional force is generated between the roll paper 20d and the platen, the roll paper 5
1 may cause wrinkles. Therefore, a plurality of platen rollers 10a to 10d are provided to reduce the frictional force and prevent the occurrence of wrinkles, and to stabilize the feeding of the roll paper 51.

In addition, when the feeding speed of the roll paper 51 is uneven between the positions of the platen rollers 10a to 10d and the positions between the platen rollers 10a to 10d, the dummy platens 11a to 11d are used to feed the roll paper 51.
1 is jammed, wrinkled, or fed diagonally, and normal printing cannot be performed. Therefore, the paper is provided to prevent such inconveniences. At this time, the reason why the dummy platens 11a to 11d were not made into rotating rollers was to increase the frictional load on the roll paper 51 by the dummy platens 11a to 11d, and to prevent the line thermal heads 20a to 20d on the same line and the platen rollers 10a to
This is because it was made to be as close as possible to the frictional force between 10d and 10d.

The platen pedestal 18 to which the platen rollers 10a to 10d and dummy platens 11a to 11d are attached extends further diagonally forward and downward from the position where the platen rollers 10a to 10d and dummy platens 11a to 11d are attached, and has a Feed rollers 30a to 30e, the surfaces of which are pasted with elastic sheets subjected to low friction treatment, form a feed roller pressure contact portion 18a. Further, a rotary cutter 7 is attached to the lower surface side of the platen pedestal 18.

The main part of the rotary cutter 7 is composed of a fixed blade member 71 and a rotary blade member 72, and the rotation of the cutter motor 73 is transmitted to the rotary blade member 72 via a reduction gear mechanism 74 etc. It rotates to cut the roll paper 51 sandwiched between the fixed blade member 71 and the rotary blade member 72.

On the other hand, the movable lid member 6 has a front die-cast part 6
1 and a rear sheet metal part 62. Line thermal heads 20a to 20d are attached to the inner rear part of the front die-casting part 61, and feed rollers 30a to 30 are attached to the inner front part.
0e is attached.

The line thermal heads 20a to 20d are flat type line thermal heads, and the line thermal heads 20a and 20c in the front row apply a predetermined pressure to the platen rollers 10a and 10c with the printing section facing backward (to the left in FIG. 3). The line thermal heads 20b and 20d in the rear row are attached to the platen roller 10 with the printing section facing forward (to the right in FIG. 3).
b and 10d so as to be in pressure contact with each other with a predetermined pressure. As a result, the line thermal heads 20a to 20d are arranged in a staggered manner with their positions and orientations being staggered with respect to the sub-scanning direction.

In this way, a plurality of line thermal heads 20a
~20d are arranged in a staggered manner with different positions and orientations in the sub-scanning direction.
In addition to preventing printing omissions between the line thermal heads 20a to 20d, the interval in the sub-scanning direction between the line thermal heads 20a to 20d is narrowed to facilitate adjustment of the printing timing of the line thermal heads 20a to 20d. This is to improve printing quality.

As a result of arranging a plurality of line thermal heads 20a to 20d in a staggered manner with alternating positions and orientations in the sub-scanning direction, the timing for providing print control information to the line thermal heads 20b and 20d in the preceding printing phase and subsequent printing can be improved. The timing of giving the print control information to the line thermal heads 20a and 20c in the phase to be printed is shifted by the phase difference, and the order in which the print control information is given to the line thermal heads 20b and 20d in the phase to be printed in advance is changed from the timing in which the print control information is given to the line thermal heads 20b and 20d in the phase to be printed in the preceding printing. phase line thermal head 2
Needless to say, it is necessary to reverse the order in which print control information is given to 0a and 20c.

The mounting portions of the line thermal heads 20a to 20d of the front die-cast portion 61 of the movable lid member 6 include
Front row line thermal heads 20a and 20c
and the line thermal heads 20b and 20 in the back row.
A tension portion 61a is provided to protrude downward between d and d. When the movable lid member 6 is closed, the tension portion 61a is connected to the front row of platen roller 10a, dummy platen 11b, platen roller 10c, and dummy platen 11d, and the rear row of dummy platen 11a, platen roller 10b, dummy platen 11c, and platen roller. 10b so as to enter below the upper end surfaces of the platen rollers 10a to 10d, and when the movable lid member 6 is closed, the platen roller 10a of the front row, the dummy platen 11b, the platen roller 10c and the dummy It serves to apply tension to the roll paper 51 stretched between the platen 11b and the dummy platen 11a, platen roller 10b, dummy platen 11c, and platen roller 10d in the rear row. With the movable lid member 6 closed, the tension section 61a applies tension to the roll paper 51, so that the roll paper 51 can be moved to the front and rear platen rollers 10a simply by closing the movable lid member 6.
and 10c and platen rollers 10b and 10
d, and the platen rollers 10a and 10
To eliminate overlapping line printing by line thermal heads 10b and 10d in the rear row at the start of printing caused by slack in roll paper 51 between c and platen rollers 10b and 10d, and to prevent the occurrence of wrinkles in roll paper 51. I can do it.

As shown in FIG. 7, each feed roller 30a to 30e is fixed by press-fitting fixing rings 33a and 33b into both ends of a roller cylinder 31 thickly coated with an elastic body 32 made of rubber or the like. are inserted through the peripheral surface of the cylindrical feed shaft 34, and fixing rings 33a and 33b are screwed and fixed to the feed shaft 34 at positions 180° apart by screws 35a and 35b.

In this way, each feed roller 30a to 30e
At two 180° different positions on both ends of the feed rollers 30a to 30e, use a pair of screws 35a and 35b.
By screwing and fixing at the points, the screw fixing work is reduced compared to the conventional method of fixing the feed roller at two locations 180 degrees apart at both ends, for a total of four locations. This provides advantages such as eliminating the need for balance adjustment between each screw, as well as eliminating the need for multiple feed rollers 30a to 30a.
In a printing device equipped with 30e, higher accuracy can be obtained, and paper feeding can be performed smoothly.

Although not particularly shown, the feed shaft 34
The feed shaft 34 is inserted into a pair of left and right oval guide shaft holes bored in the rotating side plate 55 (see Fig. 4) and is prevented from coming out by a bushing. It is arranged so that it can slide inside. In addition, as shown in FIG. 2, the feed shaft 34 has
Feed shaft pressing rings 42 are attached at equal intervals between the feed rollers 30a to 30e and at both ends, and as can be seen from FIG. A plurality of leaf spring members 43 arranged at equal intervals in the axial direction of the feed shaft 34 of the portion 61 bias the feed rollers 30a to 30e so as to press against the feed roller pressure contact portion 18a of the platen pedestal 18.

By the way, the feed rollers 30a to 30e are
The number of line thermal heads 20a to 20d is different from that of the line thermal heads 20a to 20d. Line thermal head 20a~
At the position where the rollers 20d overlap, one of the feed rollers always corresponds to the position. The feed rollers 30a to 30e are arranged in this way because the line thermal head 20a
At the overlapping position of ~20d, an additional load is applied to the roll paper 51 due to the contact pressure of the line thermal heads 20a to 20d, and there is a risk that the paper cannot be fed evenly. This is to ensure that this is done.

As shown in FIG.
6 is fixed thereto, and this feed pulley 36 is connected to a feed motor 39 via a timing belt 37 and a reduction gear mechanism 38.

The tension of the timing belt 37 is adjusted by a tension adjustment mechanism 40, and the timing belt 37 is stretched around the feed pulley 36 via an idle gear 41 that changes the direction of the load applied to the feed shaft 34.

As shown in FIG. 3, a circuit board 45 and the like are disposed on the rear sheet metal portion 62 of the movable lid member 6.
It is shielded by a decorative plate 46 so that it is not exposed to the outside when the movable lid member 6 is opened. Note that a paper guide section 47 is attached to the decorative board 46, and a paper empty sensor 48 consisting of a micro switch is provided on the paper guide section 47.

Further, on the upper surface of the movable lid member 6, as shown in FIG. 1, an operation panel 63 for the enlarged print 1 is provided.

As shown in FIG. 4, the fixed base 5 and the movable lid member 6 are arranged so that the movable lid member 6 is attached to a pivot shaft 54 implanted near the rear end of a fixed side plate 81 fixed to the fixed base 5. Rotating side plates 55 fixed to both sides of the inner surface are rotatably attached, thereby connecting them to each other.

One end of an air damper 23 is swingably supported on a pin 22 near the front end of a support plate 21 (see FIG. 9) that integrally extends outward from the fixed side plate 81 and stands upright. The other end of the air damper 23 is swingably supported by a pin 24 implanted near the rear end of the rotating side plate 55. Therefore,
During normal life, the rotational side plate 55 is given a rotational force that causes it to rise upward about the rotational support shaft 54 due to the elasticity of the air damper 23 .

As shown in FIG. 9, support shafts 82 are implanted in fixed side plates 81 provided on the left and right sides of the fixed base 5, respectively, and a swing lever 8 is attached to the support shafts 82.
3 is pivotally mounted so that it can swing freely. As shown in FIG. 8, the swing lever 83 rotates clockwise around the support shaft 82 by a compressible coil spring 86, which has one end attached to the swing lever 83 and the other end fixed to the fixed side plate 81. (in FIG. 8). The rotation of the swing lever 83 due to the elasticity of the coil spring 86 is regulated at a predetermined position by a stopper pin 81a implanted in the fixed side plate 81. In addition, the coil spring 86
The rotation of the swinging lever 83 against the elasticity of the 12th
As shown by the dashed line in the figure, it is regulated at a predetermined position by a stopper pin 81b implanted in the fixed side plate 81.

One end of an operating rod 84 is fixed to the lower end of the swing lever 83, and a grip ball 84a is attached to the other end of the operating rod 84.

Further, a pin 85 is implanted at the upper end of the swing lever 83 to engage with a cam plate 87 and a cam member 88 (see FIG. 9) fixed to the inner surface of the swing side plate 55. A pressing piece 83a made of a bent piece is formed at the upper end of the L-shape of the movable lever 83. This pressing piece 83a is adapted to engage with a lid open detection sensor 89, which is a micro switch attached to the rotating side plate 55.

As shown in FIGS. 10a and 10b, the cam plate 87 is formed of a plate with a step in the middle, and has a cam surface 87a that engages with the pin 85 and a locking piece 87b on its upper end surface. is provided. The cam member 88 has a slanted cam surface 88a at its lower end, and is integrally joined to the upper inner surface (left side in FIG. 10b) of the cam plate 87 by welding or the like. A cam plate 87 whose lower part is fixed to the outer surface of the rotating side plate 55 with screws or the like is bent at the upper part and extends inside the rotating side plate 55 through a through hole 55a formed in the rotating side plate 55. It's being served. A cam member 88 fixed to the inner surface of the upper part of the cam plate 87
is located inside the rotating side plate 55.

On the other hand, as shown in FIG. 1, the image reading section 2 opens the lid member 2a, places the original on a document table (not shown), closes the lid member 2a again, and presses the reading switch 2b. When operated, the image of the document is read as digital image information by a built-in line image sensor (not shown). The image reading section 2 is capable of transferring the read digital image information to the enlarged print section 1 via a cable (not shown).

Next, the operation of the large-sized printing apparatus of this embodiment configured as described above will be explained.

First, in order to set the roll paper 51 in the enlarged print section 1, hold the grip balls 84a of the operation rod 84 that protrudes to the left and right lower sides of the fixed base 5 in both hands, and press the grip balls 84a toward the front side (counterclockwise in FIG. 8). ). Then, as shown in FIG. 11, the swing lever 83 rotates around the support shaft 82 against the elasticity of the biasing spring 86, and the pin 85 moves. As a result, the pin 85 slides down the cam surface 87a of the cam member 87, and as shown in FIG.
Detects the opening of. As the pin 85 continues to move, the pin 85 finally touches the cam surface 87a of the cam member 87.
When the movable lid member 6 is released from the fixed base 5, the movable lid member 6, which is no longer regulated by the pin 85, is rotated together with the rotation side plate 55 around the rotation support shaft 54 due to the elasticity of the air damper 23. The movable lid member 6 is opened. After this, the swing lever 83 collides with the stopper pin 81b and becomes unable to rotate any further, allowing the user to press the operating rod 84.
When the lever is released, the swing lever 83 moves back around the support shaft 82 due to the elasticity of the coil spring 86 to the position where it abuts against the stopper pin 81a.

In the open position of the movable lid member 6, the line thermal heads 20a to 20d and the feed roller 30
a to 30e are separated from the platen rollers 10a to 10d, dummy platens 11a to 11d, and platen pedestal 18, and the paper roll 50 can be stored in the paper roll storage section 5a.

In order to store the paper roll 50 in the paper roll storage section 5a, as shown in FIG. The paper roll 50 is placed within a certain range of the upper end surface of the supporting plate body 53, and then the paper roll 50 is pushed backward while being rolled. Then, the paper roll 50 rotates around the central convex shaft 52a.
When it reaches the position of the bearing recess 53a of the support plate body 53, it falls into the paper roll storage recess 5a due to its own weight, the central convex shaft 52a fits into the bearing recess 53a, and the paper roll 50 is set in a predetermined position. Ru. In this way, the paper roll 50 can be set up simply by placing the paper roll 50 in a certain permissible position and then pushing it backwards, making it extremely easy to store the paper roll 50.

Pull out the leading edge of the roll paper 51 from the set paper roll 50 and place it on the platen roller 1.
0a to 10d, the fixed blade member 71 and the rotary blade member 72 of the rotary cutter 7 are extended along the dummy platens 11a to 11d and the platen pedestal 18.
It can be inserted through the space between the enlarged print section 1 and pulled out to the front side of the lower surface of the enlarged print section 1. By doing this, the roll paper 51 can be set in the enlarged print section 1.

Further, in the open position of the movable lid member 6, platen rollers 10a to 10d, dummy platens 11a to
11d, line thermal heads 20a to 20d,
Since the feed rollers 30a to 30e and the like are exposed to the outside, maintenance such as repair and replacement can be performed easily. Furthermore, by removing the decorative board 46, maintenance of the circuit board 45 and the like can be easily performed.

When the front side of the movable lid member 6 is pressed from above in a state in which the roll paper 51 can be set, the movable lid member 6 resists the elasticity of the air damper 23 and the rotating side plate 55 rotates around the pivot shaft 54. is closed by In the process of closing the movable lid member 6, the cam plate 87
The cam surface 8 of the cam member 88 attached to the back surface of
8a, the pin 85 is moved to a position where it does not collide with the cam plate 87 (the swing lever 83 is moved by the coil spring 8
6), and then the pin 8
5 rides over the cam surface 88a of the cam member 88 and stops at the position where it comes into contact with the cam surface 87a of the cam plate 87 as shown in FIG. In this state, the movable lid member 6 is not in a completely closed state, and the user further holds the grip balls 84a of the left and right operating rods 84 in both hands and pushes them firmly downward.
The pin 85 pushes up the cam surface 87a of the cam plate 87 and stops at the position where it hits the locking piece 87b, and the movable lid member 6 is locked against the fixed base 5 and is completely closed. In this state, the pressing pieces 83a of the left and right swinging levers 83 are moved back, so that these pressing pieces 83a and the left and right rotating side plates 5
5 and lid open detection sensors 89 provided respectively are engaged with each other. Then, due to the simultaneous detection action of both lid open detection sensors 89 due to these engagements, when the movable lid member 6 is opened by a display member (not shown) provided on the operation panel 63, for example, a light emitting diode, etc. The operator can confirm that the movable lid member 6 is closed by the display mode in which the lit light goes out, and the paper empty sensor 48 detects whether the roll paper 5 is closed due to the expansion of the roll paper 51.
1 is detected.

As a result of the above, the line thermal heads 20a to 2
0d and feed rollers 30a to 30e are connected to platen rollers 10a to 10d via roll paper 51.
and the platen pedestal 18, and the roll paper 5
1 is set in the enlarged print section 1.

Next, open the cover member 2a of the document reading section 2, set the document on the document table, close the cover member 2a again, and press down the reading switch 2b. scans the original and transfers the digital image information of the original to the enlarged print section 1 via a cable (not shown).

In the enlarged print section 1, the digital image information transferred from the original reading section 2 is temporarily stored and held in a page memory (not shown).

When the roll paper 51 is set in the enlarged print section 1 and the digital image information of the document is stored in the page memory, the operation panel 63 of the enlarged print section 1 is opened.
When the start switch provided on the printer is pressed down, the printing operation is started.

When the printing operation is started, the feed motor 39 rotates, and the feed shaft 34 is rotated via the reduction gear mechanism 38, timing belt 37, and feed pulley 36. As a result, the feed rollers 30a to 30e rotate and the roll paper 51 is fed. At the same time, the line thermal heads 20a to 20d are driven based on the digital image information stored in the page memory, and printing is sequentially performed on the roll paper 51. Note that at this time, the line thermal heads 20a to 20d are
Needless to say, the driving is performed in consideration of the phase difference and driving order based on the position and orientation in the sub-scanning direction.

The printed roll paper 51 discharged from the enlarged print section 1 is fed while hanging downward due to its own weight, and its leading end reaches the paper tray 3 attached to the support frame 4, as shown in FIG. 13a. After that, when the roll paper 51 is sequentially discharged, the upright end of the paper tray 3 serves as the ratchet part 3b, so the roll paper 51 is sequentially folded on the paper tray 3 as shown in FIG. 13b. You can receive it by stacking it on top of each other.

When printing for one page is completed, driving of the line thermal heads 20a to 20d is stopped. Further, the feed motor 39 is further driven automatically or based on an external instruction to move the line thermal head 20a to the printing end position.
After the paper is fed by a distance corresponding to the distance between the position of ~20d and the position of the rotary cutter 7 which is the paper cutting position, the drive is stopped.

As a result, the printing end position of the roll paper 51 comes to the paper cutting position, and at this position, the cutter motor 74 is energized to drive the rotary cutter 7, and the roll paper 51 is cut at the print end position. The cut end of the roll paper 51 falls from the enlarged print section 1 and is captured by the paper tray 3.

[Effect of idea]

As explained above, according to the present invention, by providing a plurality of line print heads on the movable lid member side, it is easy to set up a large roll paper, and moreover, line printing can be performed with the movable lid member open. This has the effect that the head can be inspected and maintained simply and easily.

In addition, by arranging the plurality of line print heads provided on the movable lid member side in two rows in front and back in a staggered manner with their positions and orientations being alternated in the sub-scanning direction, the line print heads are The spacing can be narrowed, and the printing timing between the front and rear two rows of line print heads is shortened, so the number of steps of the feed motor for feeding paper between these line print heads is reduced, and problems such as eccentricity of the feed roller are reduced. This has the effect that the influence is reduced, and printing misalignment between the front and rear two rows of line print heads can be reduced.

Furthermore, by narrowing the distance between the two rows of line print heads, the printing mechanism can be made smaller, thereby making it possible to downsize the entire large printing apparatus.

Furthermore, lid opening detection sensors are provided at both ends of the movable lid member, and when the movable lid member is closed by operating the operating members provided at both ends of the fixed base, these operating members detect the opening of the lid. Since the closing of the movable lid member is detected by engagement with the sensor, for example, by operating only one detection operation member, the movable lid member is half open and not completely closed. This has the effect of preventing malfunctions in which the printing device is activated in advance.

Furthermore, by installing a paper empty sensor that detects the presence of roll paper in the paper guide section near the paper roll storage section, it is possible to reliably prevent malfunctions when roll paper is not loaded. There is.

Furthermore, by providing a tension portion protruding downward from the mounting portion between the front row line print head and the rear row line print head of the movable lid member, the tension portion closes the movable lid member. Sometimes, it comes into contact with the roll paper stretched between the front row platen and the rear row platen to apply tension, so line prints in the rear row at the start of printing caused by slack in the roll paper between the front and back two rows of platens. This has the effect of eliminating overlapping line printing by the head and preventing wrinkles from forming on the roll paper.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing a large-sized printing device according to an embodiment of the present invention, FIG. 2 is a fragmented plan view of essential parts showing an enlarged printing section of the large-sized printing device shown in FIG. 1, and FIG. is a cross-sectional view showing the internal structure of the enlarged print section shown in FIG. 2, FIG. 4 is a side view of the main part of the enlarged print section shown in FIG. 2, and FIG. Diagram 6 for explaining the setting of paper rolls in the enlarged print section
The figure is an exploded perspective view showing the structure of the platen roller and dummy platen shown in FIG. 2, FIG. 7 is a top sectional side view showing the feed roller shown in FIG. 2, and FIG. FIG. 9 is a side view showing the main parts of the opening/closing mechanism provided in the enlarged print section shown in the figure, FIG. 9 is a front view showing the main parts of the opening/closing mechanism shown in FIG. A front view and a side view showing the cam plate and the cam member shown in FIG. 9, FIG. FIGS. 13a and 13b, which are diagrams showing other operational aspects of the main parts of the opening/closing mechanism shown, are diagrams for explaining the operation of the paper tray shown in FIG. 1. In the figure, 1...Enlarged print section, 2...Document reading section, 3...Paper tray, 4...Support frame, 5...Fixed base, 5a...Paper roll storage section, 6...Movable lid member, 7...Rotary cutlet,
10a-10d... platen roller, 11a-1
1d...Dummy platen, 18...Platen pedestal, 20a to 20d...Line thermal head,
23...Air damper, 30a-30e...Feed roller, 34...Feed shaft, 39...Feed motor, 48...Paper empty sensor, 5
0... Paper roll, 51... Roll paper, 52...
Both end rim portions, 52a...Central convex shaft, 53...Support plate body, 53a...Bearing recess, 54...Rotating shaft, 55...Rotating side plate, 81... Fixed side plate, 83
... Swinging lever, 84 ... Operating rod, 85 ... Pin, 87 ... Cam plate, 88 ... Cam member, 89 ...
...This is a lid open detection sensor.

Claims (1)

[Scope of Claim for Utility Model Registration] A movable lid member is provided with an air damper to open and close freely with respect to a fixed base,
In a large-sized printing apparatus, in which the movable lid member is locked to the fixed base against the opening tendency when the movable lid member is in the closed position relative to the fixed base, a large roll paper is attached to the fixed base. A paper roll storage section for storing paper rolls and two front and rear rows of platens are provided, and the movable lid member is pivotably pivoted about a support shaft to the left and right fixed side plates of the fixed base, and the movable lid member is placed in the closed position of the movable lid member. Left and right operating rods are respectively provided to lock both ends of the movable lid member to the fixed base against the opening habit, and the movable lid member is staggered by alternating positions and orientations with respect to the sub-scanning direction. two rows of front and rear line print heads which are arranged in the shape of a movable cover member and contact the two rows of front and rear platens through the roll paper at the closed position of the movable lid member;
a rotatable feed roller that feeds and guides the roll paper after passing through the platen of the row; a paper empty sensor that detects the presence of the roll paper in a paper guide section near the paper roll storage section; and a line print in the front row. A tension portion protruding downward is provided at the mounting portion between the head and the line print head in the rear row, and a tension portion is provided on the left and right rotating side plates of the movable lid member in the closed position of the movable lid member. Left and right lid open detection sensors detect the closing of the movable lid member by being engaged with pressing pieces respectively formed on the left and right operating rods that lock both ends of the movable lid member. A large-sized printing device characterized by being provided with each.