JP2000103098A - Imaging device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent occurrence of stepwise crease in an ink ribbon when the rear end of a document sheet is drawn out after printing is performed on the surface of the document sheet by means of a thermal head and a platen roller through an ink ribbon. SOLUTION: In response to a print command from a controller, an auxiliary print part 8g elongated in the breadthwise direction of a document sheet 8 is formed in the vicinity of the rear end thereof. Since ink in an ink ribbon 15 is fused at the auxiliary print part 8g and then solidified, the ink ribbon 15 is temporarily bonded in the vicinity of the rear end of the document sheet 8. Consequently, an appropriate tension is generated in the ink ribbon 15 between the auxiliary print part 8g and the clamping part of a rotary driving platen roller 13 and a thermal head 12 even if the rear end of the document sheet 8 passes through the clamping part thus preventing occurrence of stepwise crease.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the structure of an image forming apparatus, and more particularly, to printing on a cut sheet such as a manuscript sheet via an ink ribbon, the end of the cut sheet on the upstream side of conveyance is used. The present invention relates to a configuration capable of preventing generation of step-like wrinkles in an ink ribbon when the ink ribbon comes out of a printing unit.

[0002]

2. Description of the Related Art The present applicant has previously filed Japanese Patent Application No. 10-864.
No. 72, in a state where a porous stamp face forming member containing carbon black or a light energy absorbing substance dispersed therein and having continuous cells and capable of impregnating stamp ink is pressed against a positive original, A stamp making device that melts and solidifies the surface of the stamp surface forming member corresponding to the transparent portion of the positive document by irradiating light through the stamp document. ) And a plate making unit, while a magazine containing stacked sheets of transparent film as a positive document is removably mounted on the paper feed unit, and then fed out one by one to provide an ink ribbon cartridge. It was proposed that the prints be transported to the printing unit.

On the other hand, as disclosed in Japanese Patent Application Laid-Open No. 8-301497, a printing section (image forming section) of an image forming apparatus such as a printer has a portion where a platen roller and a thermal head are sandwiched (a print heating section). When printing is performed while the cut sheet (recording medium) and the ink ribbon are superposed in parallel and conveyed, the ink in the ink ribbon solidifies after welding on the surface of the cut sheet. On the downstream side, the ink ribbon transport path is separated from the cut sheet transport path, and the ink sheet is bent at the position of the regulating roller to guide the ink ribbon toward the take-up reel, while the cut sheet is moved from the surface of the ink ribbon. It has been proposed to provide a guide plate for forcible peeling.

When it is structurally difficult to dispose a regulating roller in the printing unit, or when a guide plate having a small radius of curvature cannot be arranged on the conveyance path for conveying a cut sheet having a high rigidity. It has been considered that the downstream end (corner) of the substrate of the thermal head is bent instead of the regulating roller so that the ink ribbon transport path is separated from the cut sheet transport path.

[0005]

However, when the end (rear edge) of the cut sheet passes through the location (printing heat generating portion) between the platen roller and the thermal head, the thickness of the cut sheet is A space (gap) is suddenly generated between the ink ribbon and the surface of the platen roller and the surface of the thermal head. The ink ribbon having a weak tension is wrinkled, such as a step-like fold, so that the ink ribbon cartridge is skewed at the time of winding and the winding failure to the cartridge occurs. There was a problem.

The present invention has been made in order to solve this problem, and an object of the present invention is to provide an image forming apparatus which does not generate wrinkles such as step breaks in an ink ribbon.

[0007]

In order to achieve the above object, an image forming apparatus according to the present invention, wherein a cut sheet and an ink ribbon are conveyed to a printing section comprising a platen roller and a thermal head. In the image forming apparatus which performs printing while controlling, an auxiliary printing section for preventing relative slippage with the ink ribbon is formed at an end of the cut sheet on the upstream side of the conveyance.

[0008] The invention described in claim 2 is the first invention.
In the image forming apparatus described in (1), the auxiliary printing section is formed longer in the width direction of the cut sheet than in the transport direction of the cut sheet.

[0009]

Next, embodiments of the present invention will be described. 1 is a schematic perspective view of the stamp making apparatus, FIG. 2 is a cross-sectional view of the whole stamp making apparatus, FIG. 3 is an enlarged cross-sectional view of a main part of a magazine mounting section, FIG. 4 (a) is a plan view of an original sheet, and FIG. FIG. 9A is a plan view of an ID sheet, and FIG. 9 is an overall perspective view of a magazine body.

As shown in FIGS. 1 and 2, a large number of transparent original sheets 8 as cut sheets are laminated on the upper part of one side of a main body case 1a made of synthetic resin or the like in the stamp making apparatus 1. A magazine mounting section 3 is provided for detachably mounting the stored cassette type magazine body 2. A manual insertion slot 4 is provided adjacent to the magazine mounting section 3 for manually inserting ID sheets 9 as cut sheets one by one. In the main body case 1 a, the original sheet 8 and the ID sheet 9 are transported one by one to the printing unit 5 via the paper feeding unit 6 and the original sheet 8 printed by the printing unit 5. A xenon light-emitting unit 7 for making a predetermined stamped surface on the stamped surface member 10;

The printing section 5 includes a thermal head 12, a platen roller 13, and an ink ribbon cartridge 14. The thermal head 12 is mounted on a holder 17 with biasing means provided on the lower surface side of a cover body 16 mounted on the upper surface of the main body case 1a so as to be vertically rotatable. Thermal head 12
The ink ribbon cartridge 14 can be replaced in a state where the ink ribbon cartridge 14 is positioned outside the main body case 1a.

An ink ribbon 15 wound around a take-up reel 14b from a winding side reel 14a of the ink ribbon cartridge 14 is disposed so as to pass between the thermal head 12 and the platen roller 13. On the rotating surface of the feed roller 20, which is a rotating roller serving as a paper feeding unit in the paper feeding unit 6, is slightly adhered over substantially the entire width of the document sheet 8 (the dimension between the left and right stripe layers 8c, 8c described later). By coating and forming the material layer,
At the time of paper feeding, dust adhering to the surface of the document sheet 8 is transferred to the slightly adhesive layer of the feeding roller 20 and can be removed.

The document sheet 8 fed from the magazine 2 by the feed roller 20 passes between the guide plate 18a and the auxiliary guide plate 18b for preventing the document sheet from rising, and then passes between the ink ribbon 15 and the platen roller 13. Let through
While being intermittently transported by the platen roller 13, the thermal head 12 is operated in accordance with platemaking data such as characters and images to be plate-transmitted from an external device such as a personal computer, and a document made of a transparent film such as polyethylene terephthalate. An image to be stamped is printed on the surface of the sheet 8.

Thereafter, the original sheet 8 is sent to the plate making section 11 through a pair of rollers 22 in the downstream transfer guide section 21. As shown in FIG. 1 and FIG. 2, the plate making section 11 includes the stamp face member 10 on the upper right side of the main body case 1a.
Setting unit 24 for setting the stamp body 23 by fixing the stamp body 23 to the lower surface side from front to back and right and left, and xenon light emission that can be laterally inserted and removed from the right side of the main body case 1a into the storage chamber below the stamp body 23. And a unit 7.

The xenon light emitting unit 7 includes a transparent plate 26 disposed on the upper surface side of a unit case made of an electrically insulating material such as a synthetic resin material, a xenon tube 27 disposed below the transparent plate 26, and the transparent plate 26. A light reflecting umbrella 28 for reflecting light in the direction, a power receiving side plug fixed to the end of the unit case 25 in the insertion direction, and the like.
Connected to the power supply side plug.

The surface of the stamp face member 10 is irradiated with the light emitted from the xenon tube 27 to form a stamp face. The ID sheet 9 sent from the manual insertion slot 4 is sent to the printing unit 5 via the pair of conveying rollers 33 in the sheet feeding unit 6, where the same image as the original sheet 8 is printed, and the stamp body 23 Is discharged from the take-out port 32 through the discharge roller pair 31 in the state where no stamp exists, and is attached to a grip portion or the like of the stamp body so that the stamp surface can be easily identified.

In the lower portion of the main body case 1a, a capacitor for inputting from an external commercial power supply (100V) to supply high-voltage power to the xenon light emitting unit 7 and accumulating high-voltage power. High-voltage power supply unit equipped with a xenon tube light emission control circuit having a charging circuit for charging by charging, a charging voltage detection circuit, a xenon light emission circuit, and the like, and a CPU
And the like are arranged. FIG. 6 shows a sheet conveying drive system of the stamp forming apparatus 1 of the present invention, in which the rotational force of a first drive motor 70 in the first drive system is transmitted from a pinion gear 71 via a first power transmission system 72 composed of a plurality of gears. The rotation is transmitted to the feeding roller 20 and the conveying roller pair 33 in the paper feeding unit 6. The rotational force of the second drive motor 73 in the second drive system is
4 rotates the platen roller 13 through a plurality of gears of the second power transmission system 75, and further rotates the ink ribbon cartridge 1 through a plurality of gears 76, 77 and the like on the downstream side.
4 by rotating the take-up reel 14b.
And a first endless belt 78 such as a timing belt.
, One of the roller pairs 22 disposed between the printing unit 5 and the plate making unit 11 is driven. Further, the second
The first pulley 79 is driven via a plurality of gears of the power transmission system 75, and the second pulley that rotates integrally with the first pulley 79 and one of the discharge roller pairs 31 on the downstream side of the plate making unit 11. 80 and a second endless belt 8 such as a timing belt
1 is wound around to transmit the torque.
As described later, the control device 84 shown in FIG. 4 switches the transport drive between the first drive system and the second drive system at a predetermined timing.

Next, the structure of the original sheet 8 will be described in detail. As shown in FIGS. 4A and 4B, the original sheet 8 is a transparent synthetic resin film (for example, An image receiving layer 8b is applied and formed on the entire surface (one surface) of the base sheet 8a (polyethylene terephthalate), and a stripe layer 8c is formed by printing along both left and right edges in the longitudinal direction of the base sheet 8a. The image receiving layer 8b is for making the ink with the ink ribbon easily adhere at the time of printing in the printing section 5. For example, polyethylene terephthalate has very low polarity and excellent chemical stability. An inorganic oxidizing agent is applied to the surface of the sheet 8a, and a cyclized rubber, shellac, rosin ester, cellulose derivative, polyvinyl chloride-vinyl acetate copolymer, or the like is applied as a solid binder. Stripe layers 8c1, 8c2, 8 as mark portions
c3 is an ink layer of black or the like for discrimination by a first sensor 63 of a light reflection type or the like, a second sensor 64 of a light transmission type, or the like, which will be described later. Along a narrow band.

A mark 8d of an ink layer is provided at a position near the front end of the surface of the document sheet 8 to indicate the direction of insertion into the magazine body 2. Since the ink layers in the portions such as the stripe layer 8c and the mark 8d have higher adhesiveness than other portions, the surface of those portions is provided with an overcoat layer 8e made of a substance having a small coefficient of friction. (See the hatched portion in FIG. 4A). Thereby, when the original sheets 8 are stacked, it is possible to prevent the original sheets 8 from sticking to each other and becoming difficult to separate from each other. The sheet 8 does not adhere, so that the feeding operation can be lightened. As shown in FIG. 4A, by cutting one side corner of the rear end side of the document sheet 8 obliquely, this cutout 8f is formed on the bottom plate 43b of the inner case 43 of the magazine body 2 to be described later. When the user makes contact with the protruding portion 43e (see FIG. 11) of the rear part, the user sets the original sheet 8 on the magazine body 2 without error in the transport direction (in the embodiment, a first stripe layer described later). 8c
1 is located on the leading end side in the transport direction).

Then, as shown in FIG. 4A, the first stripe layer 8c1 is formed to be short at one side edge near the leading end side of the document sheet 8 in the conveying direction, and is formed after the first stripe layer 8c1. Second stripe layer 8c on the same side edge from the end
2, the distance (L1 + α) from the leading edge of the document sheet 8 in the transport direction to the leading edge of the second stripe layer 8c2 is determined by the distance from the first sensor 63 to the surface of the platen 13 and the thermal head 12 Is set to be slightly longer than the distance L1 to the printing portion that contacts the printing portion (the line of the heating element) (see FIG. 7A). On the other hand, the distance L2 from the printing unit to the second sensor 64 is set to correspond to the distance from the leading edge of the document sheet 8 in the transport direction to the beginning of the printing area.

Thus, according to a print command described later,
The first drive motor 70 is driven by the paper feed unit 6 on which the magazine body 2 is mounted, and one sheet of the original 8 is fed by the feed roller 20, and the start end of the first stripe layer 8 c 1 is set to the light reflection type When the blank portion (or the rear end of the first stripe layer 8c1) is detected after the detection by the first sensor 63, it is determined that the transport direction of the original sheet 8 is correct, while the second drive motor Drive 73 is started. When the starting end of the document sheet 8 reaches the position where the platen roller 13 and the thermal head 12 are sandwiched, the document sheet 8 is conveyed at a constant speed by the sandwiched portion and the feeding roller 20.

Subsequently, when the first end of the second stripe layer 8c2 is detected by the first sensor 63, the drive of the first drive motor 70 is stopped. Thereafter, only the second drive system operates. (In other words, the drive between the first drive system and the second drive system is switched), and the ink ribbon 15
Between the platen roller 13 and the thermal head 12,
The document passes along the surface of the document sheet 8 synchronously.

Next, at the position of the light-transmitting second sensing sensor 64, the starting end of the original sheet 8, ie, the first stripe layer 8
When the start end of c1 is sensed, the printing area reaches the printing section of the thermal head 12, so that a printing operation is performed, and the original sheet 8 inherited by the roller pair 22 is transferred to the plate making section 11. When the rear end of the original sheet 8 (the rear end of the second stripe layer 8c2) is detected by the light transmitting type second sensor 64, the second drive motor 73 stops driving a predetermined time after that. Thus, the document sheet 8 is stopped in a state where the front end of the document sheet 8 is nipped at the position of the discharge roller pair 31 and the rear end of the document sheet 8 is nipped by the roller pair 22. As a result, the printed portion of the original sheet 8 can be arranged substantially at the center of the plate making section 11.

On the other hand, the ID sheet 9 has a substantially rectangular shape in a plan view as shown in FIG. 5 (a), and as shown in FIG. 5 (b), one side (a side) of a base sheet 9a made of PET (polyethylene terephthalate). An image receiving layer 9b, on which the ink of the ink ribbon is easily fixed, is formed on the front surface), and an adhesive layer 9c is formed on the entire back surface of the base sheet 9a. The adhesive layer 9c is covered with a cover sheet 9e (made of PET film) having a release layer 9d such as a silicone material. Further, on the front side of the image receiving layer 9b, a stripe layer 9f as a mark portion is formed by printing with black ink or the like along the left and right side edges in the longitudinal direction of the base sheet 9a. Has a blank 9g
Are formed intermittently. The number and interval of the blank portions 9g can be determined according to the type of the ID sheet 9 (the color of the base sheet 9a, the number of portions to be printed, the size of the printing range, and the like). . As shown in FIG. 5A, a blank portion 9g is formed from the leading end on the short side of the stripe layer 9f.
(L1 + α) is set to be the same as that of the original sheet 8.

When the ID sheets 9 are inserted one by one into the manual insertion slot 4, the presence of the ID sheet 9 is confirmed by sensing the stripe layer 9f at the position of the light reflection type third sensing sensor 82 (FIG. 7 (b)), the stripe layer 9
When the third sensing sensor 82 detects a blank portion 9g between f and f, the type of the ID sheet 9 is determined, and the ID sheet 9 is displayed on a display unit 83 such as a liquid crystal provided on the upper surface of the main body case 1a.
And the like are displayed. When the first drive motor 70 starts to drive and the first sensing sensor 63 detects the beginning of the blank portion 9g (the end of the short stripe layer 9f), the second drive motor 70 operates in the same manner as in the case of the original sheet 8. 73, the platen roller 13 is rotated to transfer it to the thermal head 12 and the second sensor 6
When the start of the short stripe layer 9f is detected at 4, printing is started. Since the printed ID sheet 9 is not stopped at the plate making section 11, the ID sheet 9 is placed in the take-out port 32.
Is controlled to drive the second drive motor 73 for a predetermined period until the second drive motor 73 is released.

As described above, when the first sensing sensor 63 detects the starting end of the original sheet 8 or the ID sheet 9, the printing unit 5
Is operated to control the cueing of the sheet conveyance. When the second sensor 64 detects the start end of the document sheet 8 or the ID sheet 9, the cueing control of the printing unit is performed so as to start printing. Therefore, the manner of controlling the driving system for conveying the sheet is extremely simplified, and the configuration of the driving system is also simplified.

In this embodiment, the original sheet 8 made of PET is used.
Is 100 μm, the thickness of the base sheet 9 a of the PET ID sheet 9 is 70 μm, and the thickness of the cover sheet 9 e is 50 μm. When the thickness of these sheets is small, a tailing phenomenon occurs in which the printing portion of a line extending in a direction crossing the sheet conveying direction in the printing unit 5 becomes thicker in the conveying upstream direction. Using a thing eliminated the tailing phenomenon.

The stamp member 10 is a porous plate material containing carbon black or a light energy absorbing substance dispersed therein and having open cells so as to be able to be impregnated with the stamp ink. By irradiating light through the positive original while pressing the printed original sheet 8 which is a positive original, the surface portion of the stamp surface member corresponding to the transparent portion of the positive original is melted and solidified, while the opacity of the positive original is The surface portion of the stamp face member corresponding to the portion (light blocking portion) can produce a stamp that remains porous.

Next, referring to FIGS. 8 and 9, a push-up mechanism 35 for pressing the original sheets 8 stacked on the magazine body 2 in the direction of the feed roller 20 as a paper feeding means in the paper feeding section 6. Will be described. As shown in FIG. 8, the push-up mechanism 35 includes a pair of left and right arm portions 36,
36, a connecting piece 36b connecting between them, and the connecting piece 3
6b, at least one, preferably a pair of pressing pieces 37, 37, which are bent and formed so as to protrude upward, and a round pin-shaped protruding sideways facing the inner surfaces of the left and right arms 36, 36. Of the bases of the left and right arms 36, 36.
“a” is pivotally supported by a chassis frame or the like of the main body case 1a via pins or the like so as to be vertically rotatable.

The connecting piece 36b is located on the lower surface side of the bottom plate 3a of the magazine mounting section 3, and the pair of pressing pieces 37,
37 is disposed so as to penetrate through the through hole 41 formed in the bottom plate 3a from below, and the hooks 36c at the distal ends of the left and right arms 36, 36 and the bracket 39 projecting to the lower surface side of the guide plate 18a. The pair of pressing pieces 37, 37 are urged so as to move upward by urging means 40 such as a tension spring locked to the pair. In a state where the magazine body 2 is pulled out of the magazine mounting portion 3, the connection piece 3 of the lifting mechanism 35 is provided at an appropriate position on the lower surface of the bottom plate 3a.
6b abut substantially in parallel, and the pair of pressing pieces 37, 3
The tip of 7 largely projects from the bottom plate 3a. The rigidity of each of the pressing pieces 37 is increased by a bulging portion 37a or the like so that the pressing pieces 37 are not easily plastically deformed by a buckling force or a bending force from the tip side.

As shown in FIGS. 9, 10 (a) to 10 (c), the magazine body 2 has an outer case 42 having an open top.
And an inner case 43 having an open upper surface movable relative to the outer case 42 in a longitudinal direction (a mounting / removing direction with respect to the paper feeding unit 6), and covering a rear side of an upper surface of the inner case 43. Up and down pivotable cover 44 and inner case 43
A receiving plate 45, on which the rear side is pivotally supported and the front side is largely rotatable up and down, and on which the original sheets 8 as the cut sheets can be placed in a stack, The inner and outer cases 43 and 42 and the cover 44 are preferably formed of a synthetic resin material.

The rear end of the outer case 42 is integrally formed with a downwardly opening handle 42a which can be pushed and pulled by an operator. The front end of the bottom plate 42b of the outer case 42 has rear sides on both left and right sides. A notched section (not shown)
Engaging part 4 projecting upward at the left and right center end (free end)
8 is provided. As shown in FIGS. 9 and 10A, the left and right side plates 42c, 42c of the outer case 42 include:
A first inclined surface 49a inclined downward from the front end side toward the rear; and a downwardly convex curved surface 49b continuously provided at a lower end of the first inclined surface 49a and reaching the same height as the lower surface of the bottom plate 42b.
A second inclined surface 49c that is connected to the downwardly convex curved surface 49b and that is inclined upward; and a second inclined surface 49c that is connected to the upper end of the second inclined surface 49c and extends rearward in parallel with the bottom plate 42b. A guide portion 49 is formed, which comprises a loose fitting portion 49d formed so as to descend in the direction. Therefore, when the magazine body 2 is pulled out so as to be attached to and detached from the paper feeding unit 6, the sliding protrusions 38 protruding from the left and right arms 36 of the push-up mechanism 35 are the lower surfaces of the guides. The arm 36 (and the pressing piece 37) is vertically rotated by being slidably contacted with the first inclined surface 49a, the downwardly convex curved surface 49b, and the second inclined surface 49c. In addition, as shown in FIG. 9, from the second inclined surface 49c to the loose fitting portion 49d, the connecting corner between the bottom plate 42b and the left and right side plates 42c has:
A through hole 51 is formed, and through this through hole 51, the front end side of the horizontal sliding protrusion 38 can face the auxiliary guide portion 50 formed on the outer surface of the side plate 43c of the inner case 43. It is configured as follows.

A laterally extending rib-like auxiliary guide portion 5 integrally formed on the outer surfaces of the left and right side plates 43c of the inner case 43.
Reference numeral 0 denotes an auxiliary inclined surface 50a having substantially the same inclination angle as that of the first inclined surface 49a, and is parallel to the lower end of the auxiliary inclined surface 50a so as to be able to slide on the upper surface of the bottom plate 42b of the outer case 42. Bottom guide surface 50b and the bottom guide surface 50b
And an engagement guide surface 50c that is connected to the rear end and extends substantially vertically upward (see FIGS. 9 and 10B). Further, the pressing piece 37 of the lifting mechanism 35 is configured to be able to pass from below through an insertion hole 52 formed at a position near the front of the bottom plate 43b of the inner case 43 (see FIG. c) and FIG. 11).

As shown in FIG. 9, FIG. 10 (c) and FIG. 13, the separation frame 46 disposed at a position near the front part in the inner case 43 is formed on the inner surfaces of the left and right side plates 43c, 43c of the inner case 43. A pair of left and right side plates 46a, 46a each having a hole whose base end is rotatably supported by the pivotal support portion 53 provided on the base plate, a connection bottom plate 46b for connecting between lower ends of the both side plates 46a, 46a,
It comprises a front plate 46c raised from the front end of the connecting bottom plate 46b, and separation claws 54, 54 and the like bent substantially horizontally at both left and right ends of the upper end of the front plate 46c. The original sheet 8 stacked on the left and right corners of the front end of the receiving plate 45 pivotally supported by a pair of left and right pivots 60 (only one is shown in FIG. 10C) on the rear side of the inner case 43. The left and right corners of the front end can contact the lower surfaces of the pair of separation claws 54, 54, and the pressing piece 37 of the push-up mechanism 35 moves the connection bottom plate of the separation frame 46 in accordance with the pushing movement of the magazine body 2. When the receiving plate 45 is pushed up through a hole formed in 46b, the separating frame 46 is rotated upward through the receiving plate 45.

The separation frame 46 is provided in the inner case 43.
The lowering mechanism 56 mounted between the upper surface of the bottom plate 43b and the connecting bottom plate 46b can be lowered so as to approach the bottom plate 43b. That is, FIG. 9 and FIG.
As shown in FIG. 7, the pulling-down mechanism 56 includes a front and rear longitudinal bulging portion 43 d protrudingly formed on the upper surface side of the bottom plate 43 b of the inner case 43.
The distal end portion (connecting portion of a pair of foot portions) of the torsion bar 58 having a U-shape in a plan view in which a pair of base ends are engaged with mounting hook portions 57 protruding to both left and right sides of the separating frame body 46 is provided. The pair of foot portions of the torsion bar 58 is engaged with the inner case 4
The lowering plate 43b is configured so that the pulling-down force is reduced in a posture substantially parallel to the upper surface thereof.

As described above, when the separation frame 46 is turned upward so that the connecting bottom plate 46a is separated from the bottom plate 43b, the pair of feet of the torsion bar 58 is turned downward with the mounting hooks 57, 57 as starting points. The biasing force acts to elastically deform the convex frame to pull the separation frame 46 downward. In the middle of the separation frame 46 in the front-rear longitudinal direction of the both side plates 46a, 46a, lifting control pieces 62, 62 are formed to be bent inward. As will be described later, after the original sheet 8 stacked on the receiving plate 45 is pressed against the rotating surface of the feeding roller 20 by the push-up mechanism 35 and the sheet feeding operation is performed, the push-up mechanism 35 is rotated downward to extract the magazine body 2. Then, the uppermost one of the stacked original sheets 8 remains attached to the fine adhesive layer formed on the rotating peripheral surface of the feeding roller 20, so that the original sheet 8 is separated via the torsion bar 58 as the pulling-down mechanism. When the frame body 46 is forcibly moved downward, the separation claw 54 and the lifting regulating piece 62 are located on both sides of the feeding roller 20, so that the document sheet 8 can be efficiently separated from the feeding roller 20. .

Next, the operation of the push-up mechanism 35 at the time of inserting and removing the magazine body 2 with the above configuration will be described. In a state where the magazine body 2 is removed from the magazine mounting portion 3 of the main body case 1a, as shown in FIG. Further, in the sheet feeding unit 6, the pressing piece 37 of the push-up mechanism 35 is moved by the urging force of the tension spring as the urging means 40 so that the bottom plate 3a
In this state, the pin-like sliding projections 38, 3 of the pair of left and right arms 36, 36 of the push-up mechanism 35 in this state.
8 are arranged at a predetermined height position. Then, outer case 4
Holding the handle 42a at the rear end of the magazine body 2, the magazine body 2 is inserted into the magazine mounting section 3 from the front end thereof (the direction of arrow A in FIG. 12). With the insertion movement of the magazine body 2, the auxiliary inclined surfaces 5 of the auxiliary guide portions 50 on both the left and right sides of the inner case 43.
The first inclined surfaces 49a, 49a of the guide portions 49 on the left and right sides of the outer case 42 abut against the sliding protrusions 38, 38, and the arm portion 36 opposes the urging force of the urging means 40. , 36 are pushed downward.

The locations of the downwardly convex curved surfaces 49b, 49b on the left and right sides of the outer case 42 are combined with the sliding projections 38,
38 passes. At this time, the tips (upper ends) of the pair of left and right pressing pieces 37, 37 of the push-up mechanism 35 are at the lowest position located below the through hole 41 in the bottom plate 3a, and the magazine body 2 is placed on the pressing pieces 37, 37. It can be pushed further without distraction. When the magazine body 2 is further pushed in, the sliding projections 38, 38 slide on the bottom guide surfaces 50 b, 50 b of the inner case 43, so that the push-up mechanism 35 is maintained at the lowest position.

When the front end of the magazine body 2 is finally pushed into the predetermined position of the paper feeding section 6 and set, the sliding projections are provided on the rear sides of the engagement guide surfaces 50c on both left and right sides of the inner case 43. The tip (upper end) of the pair of left and right pressing pieces 37 of the push-up mechanism 35 urged upward by the urging means 40 so that the portions 38, 38 are located,
1. The upper surface of the receiving plate 45 is pushed upward by passing the notch 47 of the outer case 42, the insertion hole 52 of the inner case 43, and the holes 61, 61 of the separation frame 46 upward.

In this state, as shown in FIG.
The upper surface of the uppermost sheet among the original sheets 8 stacked on the sheet 5 is pressed against the feeding roller 20 in the sheet feeding section 6 with a strong pressing force. FIG. 14 is a functional block diagram of the control device 84 of the stamp creation device 1 of the present invention, which includes a ROM storing a control program, a RAM storing various data (detection values) for control, and various calculations and controls. The above-mentioned first sensor 63, second sensor 64, third sensor 82, first drive motor 70,
The second drive motor 73 and a display unit 83 such as a liquid crystal are connected, and the original sheet 8 and the ID
It is configured to control the cueing control of the conveyance of the sheet 9, the trailing edge detection, the printing operation in the printing unit 5, the stop of the original sheet 8 in the plate making unit 11, the discharge of the ID sheet 9, and the like.

When a print command is received from an external device such as a personal computer, the feed roller 20 is first rotated and driven to feed the uppermost original sheet 8 toward the transfer guide plate 18a. When the front end left and right corners of the fed original sheet 8 are separated from the separation claws 54, 54, the fed original sheet 8 can be transferred onto the transfer guide plate 18a in a flat state. When the leading edge of the original sheet 8 is detected by the first sensor 63 at the position of the auxiliary guide plate 18b, the feed roller 20 and the roller pair 22 in the downstream side transfer guide section 21 start driving, and the leading edge of the original sheet 8 is started. Is detected by the second sensor 64, the start end of the print area of the original sheet 8 reaches the heating element of the thermal head 12, and the ink ribbon is moved between the rotating platen roller 13 and the thermal head 12. Printing starts via 15. On the other hand, the platen roller 13 and the thermal head 1
2, the first drive motor 7
0 stops and the feed roller 20 rotates freely.

By the way, in the printing section 5 in the present embodiment, as shown in FIG. 15A, the heating element section 12a of the thermal head 12 (extending in the direction perpendicular to the conveying direction of the original sheet 8) is connected to the ink ribbon 15. Is melted and adhered to the surface of the document sheet 8 to print an image. Since the ink once melted is quickly solidified by air cooling, the solidified portion (ink adhesion portion) is parallel to the surface of the original sheet 8 in parallel with the ink ribbon from the heating element portion 12a to an appropriate position on the downstream side of the conveyance. The ink ribbon 15 is moved downstream of the thermal head 12 with respect to the transport path of the original sheet 8 (the horizontal direction in FIG. 15A). ) Are separated diagonally upward and downstream, so that the ink ribbon 1
5 and the original sheet 8 are peeled off.

On the other hand, when the print area is only substantially at the center of the original sheet 8 in the longitudinal direction (transport direction), the rear end of the original sheet 8 (conveyance upstream from the print area) is in contact with the ink ribbon 15. Since there is no bonding portion, FIG.
As shown in FIG. 7, the document sheet 8 and the ink ribbon 15 are easily separated from each other near the rear end of the thermal head 12. By the way, immediately after the trailing edge of the original sheet 8 has passed the pinched portion between the rotating platen roller 13 and the thermal head 12, a step corresponding to the thickness of the original sheet 8 is suddenly generated. When the thermal head 12 is approached rapidly to the surface of the platen roller 13 and the weak ink ribbon 15 is clamped at the step, the wrinkles in a stepped state occur. Due to the wrinkles, the winding direction of the ink ribbon 15 is skewed or the like, and a winding failure occurs.

Therefore, in order to solve this inconvenience, in the present invention, as shown in FIG. 15C, the controller 84 controls the vicinity of the rear edge of the original sheet 8 (for example, from the rear edge to the rear edge of the original sheet 8). A print command is issued so that an auxiliary printing unit 8g, such as a thin line-shaped auxiliary printing unit, is provided in the direction intersecting with the transport direction (width direction of the original sheet 8) and in the transport direction of the original sheet 8 at a position of about 3 mm. Is issued.

With this configuration, the auxiliary printing unit 8
g, the ink of the ink ribbon 15 is melted and then solidified, so that the ink ribbon 1 near the trailing edge of the document sheet 8
5 is temporarily adhered, even if the trailing edge of the original sheet 8 passes through the pinching position between the rotationally driven platen roller 13 and the thermal head 12, the original sheet 8 is pulled in the downstream direction of conveyance. As a result, a tension is generated in the ink ribbon 15 between the auxiliary printing section 8g and the holding portion. Therefore, as shown in FIG. 15B, even if the thermal head 12 being pressed suddenly approaches the surface of the platen roller 13, no step-like wrinkles are generated on the ink ribbon 15. In addition, since the adhesive force of the ink ribbon 15 and the document sheet 8 in the auxiliary printing unit 8g due to the solidification of the ink is weak, the ink ribbon 15 and the document ribbon 8 need to be moved in a direction away from the transport path of the document sheet 8 and the transport path of the ink ribbon 15. Thus, the ink ribbon 15 can be easily peeled off from the surface of the document sheet 8.

Instead of forming the auxiliary printing section 8g, the shape of the trailing edge 8h (the end face on the upstream side of the conveyance) of the original sheet 8 in plan view is shown in FIGS. 16 (a), 16 (b) and 16 (b). 16 (c)
As shown in the figures, the zigzag, triangular, arcuate, and other non-orthogonal portions are formed in the transport direction. In this way, by making the rear edge 8h a non-orthogonal portion in plan view, the rear edge 8h passes at once in the width direction of the document sheet 8 at the place where the platen roller 13 and the thermal head 12 are sandwiched. Therefore, immediately after the passage, a step corresponding to the thickness of the document sheet 8 does not occur long in the width direction of the document sheet 8, and the above-described wrinkles can be eliminated.

In the case of the ID sheet 9 as a cut sheet, the ink ribbon 1 can be formed by forming the auxiliary printing portion 8g or forming the rear end edge to be a non-orthogonal portion in plan view.
5 can be easily prevented from occurring. When the trailing end of the original sheet 8 conveyed to the plate making section 11 is sensed by the second sensor 64 during the printing, the roller area 22 is driven by a predetermined number of rotations to drive the printing area (plate making area) of the original sheet 8. The roller pair 22 is stopped because the central position of ()) is set at the central position of the plate making section.

Next, when the original sheet 8 stops at a predetermined position of the transparent plate 26 in the xenon light emitting unit 7, the stamp face member 10 of the stamp body 23 is pressed against the printed original sheet 8 via the stamp setting unit 24. Is made by the light emission of the xenon tube 27. When pulling out the magazine body 2 from the magazine mounting portion 3 when exchanging the document sheet 8 or the like, the operator holds the handle 42a at the rear end of the outer case 42 and pulls it in the direction of arrow B in FIG. Then, first, only the outer case 42 has the arrow B
The sliding contact projections 38 on the left and right sides of the push-up mechanism 35 are pushed toward the bottom of the magazine body 2 while slidingly contacting the second inclined guide surfaces 49c, 49c of the outer case 43. Thereby, the urging means 4
The distal end side of the arm portion 36 of the push-up mechanism 35 rotates downward against the urging force of 0, and the distal end of the pressing piece 37 descends in a direction to come out of the bottom of the magazine body 2. When the outer case 42 is further pulled, the sliding contact projection 38 reaches the position of the downwardly convex curved surface 49b of the outer case 42, and in the vicinity thereof, the tip of the pressing piece 37 completely comes out of the bottom of the magazine body 2. State.

Receiving plate 45 by the above-described push-up mechanism 35
Is released, the separation frame 35 is pulled back downward by the urging force of the torsion bar 58 of the pulling-down mechanism 56, and as a result, for example, the separation frame 35 is formed on the slightly adhesive layer formed on the rotating peripheral surface of the feeding roller 20. Even if the original sheet 8 is adhered, the separation claw 5 at the front and rear positions with the feeding roller 20 interposed therebetween.
The document sheet 8 can be forcibly pulled down by the lifting control piece 4 and the lifting control piece 62.

Next, when the outer case 42 is pulled, the engaging portion 48 at the end of the bottom plate 42b of the outer case 42
3 and comes into contact with the leading edge of the bottom plate 43b, and the inner case 43 is also pulled out rearward. At this time, the sliding projection 38 comes into sliding contact with the bottom guide surface 50c of the inner case 43, so that the bottom guide surface 50c is
Has a function of restricting access to the bottom plate 43b of the inner case 43. Further, when the sliding protrusion 38 slides on the auxiliary inclined surface 50a or the first inclined guide surface 49a, the pushing-up mechanism 35 is rotated upward by the urging force of the urging means 40. In this state, since the tip of the pressing piece 37 is located outside the tip of the magazine body 2, even if the lifting mechanism 35 returns to the original state (see FIG. 12), the pressing piece 37 and the magazine body 2 Does not interfere.

[0051]

According to the first aspect of the present invention,
At the time of printing, the heating element of the thermal head melts the ink of the ink ribbon, and the ink once melted is quickly solidified by air cooling. The ribbon and the surface of the cut sheet can move while being parallel.

Therefore, according to the present invention, if an auxiliary printing portion is formed near the rear edge of the cut sheet, the ink of the ink ribbon is melted and solidified in the auxiliary printing portion, thereby forming the rear end of the cut sheet. Since the ink ribbon is temporarily bonded in the vicinity of the edge, even if the trailing edge of the cut sheet passes through the position where the rotary head is held between the platen roller and the thermal head, the cut sheet is pulled in the transport downstream direction. Accordingly, an appropriate tension is generated in the ink ribbon between the auxiliary printing section and the holding portion. Therefore, even if the thermal head being pressed suddenly approaches the surface of the platen roller, step-like wrinkles do not occur in the ink ribbon having a weak stiffness. In addition, since the adhesive force of the ink ribbon and the cut sheet in the auxiliary printing section due to ink solidification is weak, the ink ribbon is moved in the direction away from the cut sheet transport path and the ink ribbon transport path so that the cut sheet moves. It can be easily removed from the surface.

Further, the invention described in claim 2 is the same as that in claim 1
In the image forming apparatus, the auxiliary printing section is formed longer in the width direction of the cut sheet than in the transport direction of the cut sheet. Is formed longer in the width direction of the cut sheet, and the ink ribbon is pulled uniformly in the width direction. You can do it.

[Brief description of the drawings]

FIG. 1 is a schematic perspective view of a stamp producing apparatus.

FIG. 2 is a cross-sectional view of the entire stamp making device.

FIG. 3 is a sectional view of a main part including a magazine mounting part.

4A is a plan view of an original sheet, and FIG.
FIG. 4A is an enlarged cross-sectional view taken along line IVb-IVb of FIG.

5A is a plan view of an ID sheet, and FIG.
FIG. 5A is an enlarged cross-sectional view taken along line Vb-Vb of FIG.

FIG. 6 is a side view showing a drive system.

FIG. 7A is an explanatory diagram illustrating a document sheet conveyance path,
FIG. 4B is an explanatory diagram illustrating a conveyance path of the ID sheet.

FIG. 8 is a perspective view of a push-up mechanism.

FIG. 9 is a perspective view of a magazine body.

10A is a side view of a magazine body, and FIG.
9 is a cross-sectional view taken along line Xb-Xb of FIG.
FIG.

FIG. 11 is a plan view of the inner case.

FIG. 12 is a side sectional view showing a state where a magazine body is inserted.

FIG. 13 is a perspective view illustrating a state in which a document sheet is fed.

FIG. 14 is a functional block diagram of a control device.

FIG. 15A is an explanatory view showing the relationship between the ink ribbon and the original sheet when the vicinity of the rear end of the original sheet is not printed in the printing unit, and FIG. FIG. 4 is an explanatory diagram illustrating a relationship between an ink ribbon and a document sheet when a printing unit is formed, and FIG. 4C is a diagram illustrating a plan view shape of an auxiliary printing unit.

16A is a diagram in which the trailing edge of the document sheet is formed in a zigzag shape in plan view, FIG. 16B is a diagram in which the trailing edge of the document sheet is formed in a triangular shape in plan view, and FIG. FIG. 5 is a diagram in which a rear end edge is formed in a convexly curved shape in plan view.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 stamp producing device 2 magazine body 3 magazine mounting section 5 printing section 6 paper feeding section 8 original sheet as cut sheet 8 g auxiliary printing section 8 h trailing edge 9 ID sheet as cut sheet 12 thermal head 13 platen roller 14 ink ribbon cartridge 15 Ink Ribbon 20 Feeding Roller 22 Roller Pair 33 Transport Roller Pair 84 Controller 85 Controller

Claims (2)

[Claims] 1. An image forming apparatus which prints a cut sheet and an ink ribbon on a printing section including a platen roller and a thermal head while transporting the cut sheet and the ink ribbon in an overlapping manner. An image forming apparatus which controls so as to form an auxiliary printing unit for preventing relative slippage. 2. The image forming apparatus according to claim 1, wherein the auxiliary printing unit is formed longer in the width direction of the cut sheet than in the transport direction of the cut sheet.