JP6274951B2 - Cut sheet conveyance aid - Google Patents

Description

  The present invention relates to an image forming apparatus (hereinafter referred to as a printer) that forms an image on a cut sheet, and more particularly, to a cut sheet conveyance assisting tool used to assist the conveyance of a cut sheet printed by a printer. .

  Among printers that use ink to form an image on a sheet of paper or resin, a printer that prints the sheet in the image forming unit and then heats the printed image downstream of the image forming unit to fix the ink There is. In such a printer, when a sheet as a printing medium is a long sheet such as a roll paper, the sheet portion on the upstream side of the image forming unit is nipped and conveyed by a pair of conveying rollers to be formed on the sheet. The image area is conveyed to the heating area to fix the ink.

However, in the above printer, if the printing medium is a cut sheet and there is no pair of conveyance rollers on the downstream side of the image forming unit, the conveyance of the cut sheet occurs when the rear end in the conveyance direction of the cut sheet passes through the conveyance roller. Cannot be carried out and the image area cannot be conveyed to the heating area. Therefore, a means for enabling the cut sheet to be conveyed even after the rear end of the cut sheet passes the conveyance roller is required. As the means, there is a mount described in Patent Document 1.
In Patent Document 1, a notch capable of inserting the rear end of a cut sheet (hereinafter referred to as cut sheet) in the conveyance direction is formed at the end of the mount, and the cut sheet is arranged on the front surface of the mount. In addition, it is disclosed that the rear end of the cut sheet in the conveyance direction is inserted and held in the notch of the mount. By using such a mount, the cut sheet moves together with the mount. The transport roller pair grips the mount after the cutting of the cut sheet is completed, and can transport the cut sheet. In other words, the part of the mount that is upstream of the rear end of the cut sheet functions as a part that enables the cut sheet to be conveyed. In addition, the part of the mount that supports the back side of the cut sheet is fed with the cut sheet, so it functions as a part to prevent problems during feeding such that the cut sheet buckles during feeding. It will be.

Utility model registration No. 3069033 (see Fig. 3)

By the way, the material of the cut sheet to be printed by the printer is not only paper but also a resin sheet such as a vinyl chloride sheet. Since the ink does not soak into the resin sheet, the ink dots formed on the front surface of the cut sheet in the image forming unit contain a lot of moisture. In this state, when ink dots are continuously formed on the front surface of the cut sheet, adjacent ink dots are adsorbed and the graininess of the printed image is deteriorated. For this reason, the image forming unit is provided with heating means for heating the back side of the cut sheet, thereby promoting the evaporation of moisture to the ink dots formed on the front surface of the cut sheet. However, in such a printer, when the mount described in Patent Document 1 is applied at the time of transporting a cut sheet, the following problem occurs.
The mount described in Patent Document 1 is arranged between the cut sheet and the heating means. For this reason, heat transfer to the cut sheet becomes poor, moisture of the ink dots is not sufficiently evaporated, and there is a possibility that the granularity of the printed image is deteriorated. In addition, since the cut sheet and the mount are not completely in close contact with each other, a part that is in contact with each other and a part that is not in contact with each other are generated, and the heat distribution in the cut sheet surface is not uniform. The non-uniformity of the heat distribution in the cut sheet surface may partially deteriorate the image quality of the printed image. As described above, the mount disclosed in Patent Document 1 can support the back surface of the cut sheet and prevent problems during paper feeding, but on the other hand, there is a problem that the printed image is deteriorated.
Then, this invention is providing the cut sheet conveyance auxiliary tool which does not produce the problem mentioned above.

  One aspect of the present invention relates to a cut sheet conveyance assisting tool used for assisting conveyance of a rectangular cut sheet printed by an image forming apparatus. The cut sheet conveyance assisting tool includes a first sheet member configured to be attachable to the cut sheet, and a second sheet member configured to be attachable to both the first sheet member and the cut sheet. . Said 1st sheet | seat member is provided in the edge part of a 1st sheet | seat member, and has an attaching part which can clamp the 1st edge of the said cut sheet | seat. Further, the second sheet member includes a grip portion that grips the cut sheet and a fixing portion that removably fixes the second sheet member to the first sheet member. The gripping portion is configured such that the second edge opposite to the first edge of the cut sheet is in a free state, and the third edge adjacent to the first edge and the second edge of the cut sheet And the fourth end edge is detachably gripped.

According to the cut sheet conveyance auxiliary tool of the above aspect, when the user attaches the rear edge (first edge) in the conveyance direction of the cut sheet to the attachment portion of the first sheet member, The first sheet member extends from the edge. Therefore, even if the trailing edge passes through the conveyance roller pair in the conveyance of the cut sheet, the conveyance roller pair nipping and conveying the first sheet member, the cut sheet that is not nipped by the conveyance roller pair, It can be conveyed to an area on the downstream side of the image forming unit.
Further, the second sheet member is placed on the first sheet member attached to the rear edge of the cut sheet, and two side edges (third of the cut sheet in the direction intersecting the conveying direction) are arranged. And the fourth edge) can be gripped by the gripping portion, and the end of the second sheet member opposite to the gripping portion can be fixed to the first sheet member by the fixing portion. When the user attaches the second sheet member in this way, the cut sheet is not buckled. Therefore, the user can reliably supply the front end (second end edge) of the cut sheet to the nip portion of the conveying roller pair.
In addition, the gripping unit is configured to grip the two side edges of the cut sheet in a direction intersecting the conveyance direction with the leading end of the cut sheet in a free state. For this reason, the user removes the fixing portion of the second sheet member from the first sheet member after supplying the leading end of the cut sheet to the nip portion of the conveying roller pair, and removes the second sheet member in the sheet conveying direction. It can be easily pulled out upstream. That is, the user can remove the second sheet member from the first sheet member when the leading end of the cut sheet reaches the nip portion of the conveying roller pair. Therefore, in a printer that fixes a printed image formed on a cut sheet by a heating unit, the cut sheet can be conveyed without blocking heat to the cut sheet.

  According to the present invention, it is possible to prevent a low-rigidity cut sheet from buckling when the sheet is supplied to the pair of conveyance rollers, and to convey the cut sheet to an area downstream of the image forming unit (for example, a fixing area). It becomes. In addition, the cut sheet can be conveyed without hindering heat transfer to the cut sheet.

1 is a schematic cross-sectional configuration diagram of a printer apparatus main body according to a first embodiment. FIG. 3 is a perspective view of an image forming unit and a fixing area according to the first embodiment. The cross-sectional block diagram of the guide sheet which concerns on a 1st Example. The perspective view which showed a mode that the guide sheet which concerns on a 1st Example was attached to a cut sheet. FIG. 6 is a diagram for explaining a sheet feeding auxiliary sheet according to the first embodiment. FIG. 6 is a diagram for explaining a sheet feeding auxiliary sheet according to the first embodiment. The perspective view which showed a mode that the guide sheet which concerns on a 2nd Example was attached to a cut sheet. FIG. 6 is a diagram for explaining a sheet feeding auxiliary sheet according to a second embodiment.

Next, embodiments of the present invention will be described with reference to the drawings.
(First embodiment)
FIG. 1 shows a schematic sectional configuration of a printer according to a first embodiment of the present invention. The printer apparatus main body 1 shown in this figure includes an image forming unit 3 that forms an image on a sheet S (rolled sheet or cut sheet) as a printing medium, a conveyance roller 8 that conveys the sheet S, A pinch roller 9 that presses the sheet S against the conveyance roller 8 and is driven by the rotation of the conveyance roller. The sheet conveying means including the conveying roller 8 and the pinch roller 9 is installed only upstream of the image forming unit 3 in the conveying direction of the sheet S. Further, the printer apparatus main body 1 includes a conveyance guide pair 22 that guides the sheet S toward such a sheet conveyance unit, a paper feeding unit 20 for inserting the sheet S into a space between the conveyance guide pair 22, Is provided.
The image forming unit 3 supports a head 4 that ejects ink as a printing liquid, a carriage 5 that is mounted with the head 4 and can reciprocate in the width direction (main scanning direction) of the sheet S, and the sheet S from the back surface. And a platen 6 that holds the sheet S in a substantially flat surface by suction. A platen heater 14 is installed on the back surface of the platen 6. A blower fan 17 that blows air toward the sheet S on the platen 6 is installed on the front surface side of the platen. In the conveyance path between the conveyance guide pair 22 on the upstream side of the image forming unit 3, a detection sensor 7 that detects the sheet S, a temperature sensor 12, and a conveyance path heater 15 that heats the sheet S from the back surface are installed. ing. Further, a fixing area 10 that promotes fixing of the ink discharged on the front surface of the sheet S is provided downstream of the image forming unit 3. A temperature sensor 13, a sheathed heater 16, and a blower fan 18 are installed in the fixing area 10, and a sheet discharge port 25 for discharging the sheet S is formed at the most downstream side of the fixing area 10. The sheathed heater 16 is a heater that heats the sheet surface with radiant heat.

Next, referring to FIG. 1, an image forming process and an ink heating process in the printer including the above-described components will be described in this order.
a) Image Forming Process The sheet S is inserted from the supply unit 20 by the user's hand and sandwiches the sheet S between the conveyance roller 8 and the pinch roller 9 via the conveyance guide pair 22 (hereinafter referred to as a nip portion). .) Thereafter, the sheet S sandwiched between the transport roller 8 and the pinch roller 9 is transported downstream in the transport direction as the transport roller 8 rotates, and an image is formed on the sheet S by the image forming unit 3. Is done. In the image forming unit 3, the carriage 5 is moved forward or backward in the main scanning direction while the conveyance of the sheet S is stopped. At that time, ink droplets are ejected from the head 4 to the sheet S to print one line. Do. When printing for one line is completed, the sheet S is conveyed by a predetermined amount in the direction of the arrow (sub-scanning direction) perpendicular to the main scanning direction, and the carriage 5 moves forward or backward again to continue. Is printed for one line. In this way, the sheet S is repeatedly formed and image formation is performed for each line while repeating intermittent conveyance.
b) Ink Heating Process The ink heating process is performed in the image forming unit 3 and the fixing area 10 downstream thereof. Therefore, the ink heating process will be described separately for a heating process in the image forming unit 3 and a heating process in the fixing area 10 downstream of the image forming unit.

  First, the heating process in the image forming unit 3 will be described. The printer of this embodiment prints not only on paper but also on a water-repellent sheet represented by a vinyl chloride sheet. In the water repellent sheet, the ink does not soak into the sheet even if the ink droplets land on the sheet surface. For this reason, when ink droplets in a state containing a large amount of water come close to each other on the sheet surface, the ink droplets stick to each other and form large ink droplets. Then, the granularity of the printed image is deteriorated and the image quality is deteriorated. Such a phenomenon is called beading, and the device is required to make it difficult to cause beading. That is, the ink droplets that have landed first after the ink droplets ejected from the head 4 by the forward movement of the carriage 5 land on the sheet S and before the landing of the next ink droplet by the backward movement of the carriage 5 are reached. It is necessary to provide the printer with a function for promoting moisture evaporation. In the present embodiment, moisture evaporation of ink droplets is promoted by blowing air to the printing area while maintaining the surface temperature of the sheet S during printing at 50 ° C. to 60 ° C. Management of the surface temperature of the sheet S uses a temperature sensor 11 that measures the sheet surface temperature by infrared rays, and feeds back temperature information from the temperature sensor 11 to the control unit of the printer to perform PID control of the platen heater 14. Is done. The heat generated in the platen 14 is transferred to the sheet S through the platen 6 and promotes evaporation of moisture contained in the ink droplets on the sheet S. Further, the evaporation of moisture is further accelerated by the blower fan 17 that blows air toward the sheet S on the platen 6. Note that the temperature of the sheet surface set in the image forming unit 3 is referred to as a Dry temperature. For the purpose of stabilizing the Dry temperature, a temperature sensor 12 and a conveyance path heater 15 are provided in the conveyance path on the upstream side of the image forming unit 3, and the temperature of the sheet surface is maintained at 50 to 60 ° C. Further, the temperature of the conveyance path heater 15 set on the upstream side of the image forming unit 3 is referred to as Pre temperature. In particular, in a medium having a large heat capacity (a medium to be printed), it takes time to reach the Dry temperature with only the platen heater 14 and obstructs high-speed printing. Therefore, the preheating by the transport path heater 15 is significant. In this embodiment, the platen heater 14 and the conveyance path heater 15 are directly heated from the back side of the sheet S in consideration of thermal efficiency.

Next, the heating process in the ink fixing area 10 will be described. Although the image forming unit 3 is heated as a countermeasure against beading, the ink is not yet fixed on the sheet S at this stage, and the ink is easily dropped when rubbed. In the fixing area 10, heating and air blowing are performed in order to promote fixing of ink onto the paper surface. The ink used in the printer of this embodiment includes a 2 Py (2-pyrrolidone) solvent that has an effect of fixing the ink by softening the surface of the vinyl chloride sheet (referred to as an anchor effect). When the other solvent components are evaporated by heating or blowing and the concentration of the 2 Py solvent is increased, the anchor effect is sufficiently exhibited and the ink is fixed on the sheet. The fixing area 10 is heated by a sheathed heater 16 and the air is blown by a blower fan 18. In this embodiment, the surface temperature of the sheet S in the fixing area 10 is set in a range of 75 to 85 ° C. This is because if the temperature is too low, the anchor effect is not sufficiently exhibited, and if the temperature is too high, the sheet S contracts and the dimensional accuracy decreases. The sheet surface temperature set in the fixing area 10 is referred to as a cure temperature. The cure temperature is managed by using a temperature sensor 13 that measures the sheet surface temperature by infrared rays, feeding back temperature information from the temperature sensor 13 to the control unit of the printer, and performing PID control of the sheathed heater 16. Done.
As described above, in this embodiment, the beading is performed by the temperature sensors 11 to 13 that can control the Pre temperature, the Dry temperature, and the Cure temperature, the heating by the heaters 14 to 16, and the blowing by the fans 17 to 18, respectively. The process of fixing the ink to the sheet S while suppressing the above is realized.

Next, the operation after the end of image formation in the printer of this embodiment will be described with reference to FIGS. FIG. 2 is a perspective view of the image forming unit 3 and the fixing area 10 in the printer of this embodiment.
When the sheet S as the printing medium is a long sheet such as roll paper, the conveyance roller 8 and the pinch roller 9 sandwich and convey the sheet portion on the upstream side of the image area formed on the sheet S, The image area is conveyed to the fixing area 10 to fix the ink of the printed image. On the other hand, when the sheet S is a rectangular cut sheet such as a water repellent sheet or a cut sheet, the cut sheet cannot be conveyed if the rear end of the cut sheet passes through the nip portion between the conveyance roller 8 and the pinch roller 9. Therefore, the image area cannot be conveyed to the fixing area 10.

Therefore, in this embodiment, as shown in FIG. 2, when the cut sheet S1 is used as the print medium, the cut sheet S1 is used to guide the cut sheet S1 to the downstream side using the guide sheet 30 (first sheet member). S1 is conveyed to the fixing area 10. Specifically, the guide sheet 30 is attached to the rear end in the conveyance direction of the cut sheet S1, and the guide sheet 30 is nipped and conveyed by the pair of conveyance rollers 8 and 9 on the upstream side of the image forming unit 3, thereby cutting the cut sheet. S1 can be conveyed to the fixing area 10.
The guide sheet 30 has an attachment portion 30b that can be detachably attached to the rear end of the sheet S. Further, the length of the guide sheet 30 in the conveyance direction has at least a length corresponding to the stroke from the conveyance roller 8 upstream of the image forming unit 3 to the sheet discharge port 25 that is the end of the fixing area 10. As shown in FIG. 2, the image area formed on the cut sheet S <b> 1 is conveyed to the fixing area 10 by conveying the guide sheet 30 downstream by the conveyance roller pairs 8 and 9. When the image area passes through the fixing area 10 and the conveyance is performed until the attachment portion 30b on the front end side of the guide sheet 30 reaches the sheet discharge port 25, the conveyance roller pairs 8 and 9 hold the guide sheet 30 therebetween. Stop conveyance in the state of. In this state, the user removes the cut sheet S1 from the guide sheet 30 and completes a series of printing operations.

"Guide sheet 30"
Next, a detailed configuration of the guide sheet 30 will be described. FIG. 3 is a schematic cross-sectional view illustrating the configuration of the guide sheet 30 according to the present embodiment, and FIG. 4 is a perspective view illustrating a state in which the guide sheet 30 is attached to the cut sheet S1.
As shown in FIG. 3, the one end part of the guide sheet 30 has the attachment part 30b which attaches the end of the conveyance direction of cut sheet S1 so that attachment or detachment is possible. Specifically, the attachment portion 30b includes one end portion of a base sheet 30a that is a first sheet member, and a sheet piece 31 having one end fixed to the front surface of the one end portion. The sheet piece 31 is a sandwiching sheet portion that rotates like a flap with one end fixed to the front surface as a fulcrum to sandwich the cut sheet S1. A sheet-like magnet 32 is affixed to the surface of one end of the base sheet 30a that contacts the sheet piece 31. A rubber magnet sheet can be used as the magnet 32. Further, a steel sheet 33 is attached to the surface of the sheet piece 31 that contacts the magnet 32. In such a guide sheet 30, one end of the cut sheet S <b> 1 is sandwiched between the magnet 32 on the front surface of the base sheet 30 a and the steel sheet 33 of the sheet piece 31, whereby the magnetic force between the magnet 32 and the steel sheet 33. Thus, the guide sheet 30 is fixed to one end of the cut sheet S1. In addition, the attachment part 30b may be comprised by fixing the edge part of the two sheet pieces 31 to the end of the base material sheet 30a so that this base material sheet 30a may be pinched | interposed.
Further, the magnet 32 is provided with a notch 37 inclined with respect to the conveying direction of the cut sheet S1. This notch 37 is for inserting two corners of the rear edge of the cut sheet S1. The position of the cut 37 is determined so that the conveyance direction of the cut sheet S1 is not inclined with respect to the conveyance direction of the guide sheet 30. It should be noted that a plurality of cuts 37 are preferably provided so as to be compatible with the external sizes (B5 plate, A4 plate, etc.) of a plurality of types of cut sheets S1.
With the mounting portion 30b described above, the guide sheet 30 can be detachably attached to the rear edge of the cut sheet S1 in a relatively simple manner.

  The guide sheet 30 is an attachment (cut sheet) attached to the cut sheet S1 by the user for the purpose of guiding the cut sheet S1 to the downstream side of the image forming unit 3 even when the rear end of the cut sheet S1 passes the conveying roller 8. It is one of the transport aids. In addition to this purpose, the printer of this embodiment is also desired to suppress the buckling of the cut sheet S1 during sheet feeding. Therefore, in addition to the guide sheet 30 described above, the cut sheet conveyance auxiliary tool of the present embodiment suppresses buckling of the cut sheet S1 and assists the supply of the cut sheet S1 (second sheet member). 70).

  5 and 6 show a paper feed auxiliary sheet 70 as an attachment that can be attached to the cut sheet S2. For example, when the cut sheet S 1 having extremely low rigidity is used, the cut sheet S 1 is buckled in the middle of the conveyance path from the paper supply unit 20 to the conveyance roller pair 8 and 9, and the leading edge of the cut sheet S is conveyed to the conveyance roller 8. May not reach up to. In this case, the sheet feeding auxiliary sheet 70 is used for the purpose of preventing the buckling of the cut sheet S1 and facilitating the sheet supply to the nip portion of the conveying roller pair.

“Feeding auxiliary sheet 70”
FIG. 5 is a diagram showing a state in which the paper feed auxiliary sheet 70 is attached to the large cut sheet S1, and FIG. 6 is a diagram showing a state in which the paper feed auxiliary sheet 70 is attached to the small size cut sheet S1. is there. 5 and 6, (a) shows a schematic cross section in a state in which the auxiliary sheet 70 is attached over both the cut sheet S1 and the guide sheet 30, and (b) shows (a). FIG. 6 is a rear view of the state shown in FIG.
The sheet feeding auxiliary sheet 70 is formed on the base sheet 71 as the second sheet member, one end portion of the base sheet 71, a grip portion that grips the cut sheet S <b> 1, and the other end portion of the base sheet 71. A sheet-like magnet 73 fixed to the back surface. As the base sheet 71, a PET sheet having higher rigidity than cut paper or vinyl chloride sheet can be adopted. The base material sheet 71 is disposed on the printing surface side of the cut sheet S1, and has a width larger than the width of the cut sheet S1.

The grip portion is a portion that detachably grips the front edge S1a of the cut sheet S1 and the side edges S1c and S1d adjacent to the rear edge S1b opposite to the front edge S1a. Specifically, the grip portion includes a tongue-like piece 72 formed by forming a substantially U-shaped cut in the base sheet 71, and the side edge of the cut sheet S is formed by the base sheet 71 and the tongue-like piece 72. Hold S1c and S1d.
A plurality of tongue pieces 72 are provided in the width direction so as to correspond to the external sizes (B5 plate, A4 plate, etc.) of a plurality of types of cut sheets S1 (see FIG. 6). Further, a plurality of tongue pieces 72 may be provided in the sheet conveying direction. Further, since the magnet 73 is provided at the upstream end of the sheet feeding auxiliary sheet 70 in the conveying direction, the sheet feeding auxiliary sheet 70 is attached to and detached from the steel sheet 33 of the guide sheet 30 attached to the rear edge of the cut sheet S. Can be fixed as possible. Therefore, the rear end portion of the base sheet 71 on which the magnet 73 is present functions as a fixing portion for the paper feed auxiliary sheet 70.

  As described above, it is possible to arrange the sheet feeding auxiliary sheet 70 so as to overlap the front surface of the cut sheet S1, and to hold both side edges in the width direction of the cut sheet S1 with the tongue-like pieces 72. is there. Accordingly, buckling of the cut sheet S1 can be suppressed by the rigidity of the base sheet 71 when the cut sheet S1 is supplied to the nip portion of the conveying roller pair.

  In addition, when the auxiliary sheet 70 is attached to the cut sheet S1, the leading end of the cut sheet S1 in the conveying direction is protruded from the auxiliary sheet 70 by about 20 mm to be free. As a result, as shown in FIGS. 5 and 6, the relative position of the sheet feeding auxiliary sheet 70 with respect to the guide sheet 30 varies depending on the sheet size in the sheet conveying direction. Therefore, when the user attaches the auxiliary sheet 70 to the cut sheet S1, it is necessary to clarify the position of the auxiliary sheet 70 in the conveyance direction. For this reason, a marking line is drawn on the front surface of the sheet piece 31 of the guide sheet 30 as a mark for aligning the rear edge of the auxiliary sheet 70. Further, the leading edge of the cut sheet S1 is projected from the auxiliary sheet 70 as described above so that the leading edge of the cut sheet S1 is brought into direct contact with the nip portion of the pair of conveying rollers 8 and 9. That is, it is a consideration for the cut sheet S1 to take a vertical posture with respect to the conveying roller 8 by the nip portion.

  When the sheet detection sensor 7 installed upstream of the conveying roller pair 8 and 9 detects the cut sheet S1, the conveying roller pair 8 and 9 are rotated by a predetermined amount (corresponding to about 5 mm) after a while. I do. By this rotational driving, the leading end portion of the cut sheet S1 is sandwiched between the nip portions of the pair of conveying rollers 8 and 9. In this state, the leading end portion of the auxiliary paper feeding sheet 70 is not sandwiched between the conveying roller pairs 8 and 9. At this stage, since the auxiliary sheet 70 finishes the role of reliably supplying the cut sheet S1 to the pair of conveying rollers 8 and 9, the user removes the rear end portion of the auxiliary sheet 70 from the guide sheet 30. The auxiliary sheet 70 is pulled out upstream in the sheet conveyance direction. As a result, the tongue-like portion 72 of the auxiliary sheet 70 is moved to the upstream side while being guided along the side edges S1c and S1d of the cut sheet S1. When the tongue-like piece 72 reaches the guide sheet 30, it is elastically deformed by the guide sheet 30 and is disengaged from the side edges S1c and S1d of the cut sheet S1.

  As described above, the sheet feeding auxiliary sheet 70 is removed from the cut sheet S1 after the role of maintaining the leading end shape when the cut sheet S1 is supplied, and only the cut sheet S1 is transferred to the image forming unit by the conveying roller 8. It is conveyed to 3. Therefore, the sheet member is not interposed between the cut sheet S1 and the platen 6 during the image formation as in the prior art described above, and the heat transfer from the heater on the back side of the platen 6 is not hindered.

(Second embodiment)
Further, a second embodiment will be described. Here, the description of the same points as in the first embodiment will be omitted, and only the different points will be described. FIG. 7 is a perspective view showing how the guide sheet 30 according to the second embodiment is attached to the cut sheet S1. FIG. 8 is a view showing a state in which the auxiliary sheet feeding sheet 70 according to the second embodiment is attached to the cut sheet S1. In FIG. 8, (a) shows a schematic cross-section in a state where the auxiliary sheet feeding sheet 70 of another embodiment is attached over both the cut sheet S1 and the guide sheet 30, and (b) shows ( It is a back view of the state shown to a), and is a figure only drawing paper feed auxiliary sheet 70 and cut sheet S.

In the second embodiment, the attachment portion 30b that uses magnetic force to attach the guide sheet 30 to the cut sheet S1 in the first embodiment is replaced with an adhesive means that uses adhesive force. Specifically, an adhesive paste surface 34 is formed on the surface of one end portion of the guide sheet 30 that contacts the sheet piece 31. The adhesive paste surface 34 is an adhesive surface formed by forming a weak adhesive into a film shape that can be repeatedly bonded and peeled off the cut sheet S1 and the sheet piece 31. The back surface of the cut sheet S1 is affixed to the adhesive paste surface 34. When the user attaches the cut sheet S1 to the guide sheet 30, there should be a mark for aligning the rear edge of the cut sheet S1. For example, a marking line as indicated by a dotted line in FIG. 7 may be drawn on the front surface of one end portion of the guide sheet 30.
The adhesive glue surface 34 has a larger area in the width direction than the maximum sheet size that can be printed by the printer 1. Therefore, as shown in FIG. 7, after pasting the rear edge of the cut sheet S1 to the adhesive glue surface 34, when the back surface of the sheet piece 31 is brought into contact with the front surface of one end portion of the guide sheet 30, The sheet piece 31 is bonded to the adhesive paste surface 34.

  Even when the adhesive force is used to attach the guide sheet 30 as described above, the flap shape is adopted for the attachment portion 30b. For example, a cut sheet S1 having a size smaller than the guide sheet 30 is formed on the adhesive paste surface 34. This is to avoid exposing the adhesive paste surface 34 even when it is attached. If the adhesive glue surface 34 is exposed, it may stick to the conveyance guide pair 22 or the pinch roller 9 and cause damage to the cut sheet S1 or a conveyance failure. A sheet piece 31 (cover sheet) is provided. In addition, when the size of the sheet S to which the guide sheet 30 is attached is one type, or when the adhesive glue surface 34 is slightly narrower in the width direction than the minimum sheet size that can be printed by the printer 1, the sheet piece 31 need not be provided.

  Next, the auxiliary paper feed sheet 70 in the second embodiment will be described. One end on the downstream side of the sheet feeding auxiliary sheet 70 is a side edge of the cut sheet S1 by the tongue-like piece 72 in a state where the leading edge S1a in the conveyance direction of the cut sheet S1 is protruded as in the first embodiment. Hold S1c and S1d. On the other hand, one end on the upstream side of the auxiliary sheet 70 is fixed to the front surface of the guide sheet 30 by an adhesive paste surface 74. The adhesive paste surface 74 is made of a weak adhesive that can repeatedly bond and peel the auxiliary sheet 70 to be fed.

The means using the adhesive force described above has a simple configuration and can be manufactured at a lower cost than the means using the magnetic force shown in the first embodiment. However, in terms of durability during repeated use and workability during installation, the means using the magnetic force of the first embodiment is slightly superior to the bonding means.
Note that the auxiliary sheet feeding sheet 70 in the second embodiment may be combined with the guide sheet 30 in the first embodiment. Further, in the first embodiment, the steel sheet 33 is provided on the sheet piece 31 constituting the attachment portion 30b, and the magnet 32 is provided on the surface portion of the base sheet 30a that contacts the sheet piece 31. It is not limited to the configuration. For example, a magnet may be provided on the sheet piece 31 and a steel sheet 33 may be provided on the base sheet 30 a, or the steel sheet 33 may be replaced with a magnetic sheet-like magnet different from the magnet 32. Furthermore, the sheet piece 31 and the base sheet 30a may be made of different magnetic materials. Eventually, the sheet piece 31 and the surface portion of the base sheet 30a in contact with the sheet piece 31 should have at least magnetism for attracting them together.

According to the cut sheet conveyance assisting tool composed of the guide sheet 30 and the sheet feeding assisting sheet 70 of each embodiment described above, the following operations and effects are achieved.
When the user attaches the attachment portion 30b of the guide sheet 30 to the rear end edge S1b in the conveyance direction of the cut sheet S1, the base sheet 30a extends backward from the rear end edge S1b in the conveyance direction of the cut sheet S1. Therefore, even if the rear end of the cut sheet S1 passes through the conveyance roller pairs 8 and 9, the conveyance roller pair nipping and conveying the base sheet 30a, the cut sheet S1 that has passed through the conveyance roller pair is image-formed. It can be conveyed to a region (fixing area 10) on the downstream side of the section 3 (FIG. 2).

  Further, the base sheet 71 of the auxiliary sheet 70 is placed on the guide sheet 30 attached to the rear edge S1b of the cut sheet S1, and the side edge of the cut sheet S1 in the direction intersecting the conveying direction is arranged. The edges S1c and S1d can be held by the tongue-like piece 72 on the front end side of the base sheet 71, and the rear end of the base sheet 71 can be attached to the guide sheet 30 by the magnet 73 or the adhesive glue surface 74. When the user attaches the auxiliary sheet 70 as described above, the cut sheet S1 is not buckled due to the rigidity of the base sheet 71 (FIGS. 5 and 6). Therefore, the user can reliably supply the leading end of the cut sheet S1 to the nip portion of the pair of conveying rollers 8 and 9.

  In addition, the sheet feeding auxiliary sheet 70 is configured to hold the side edges S1c and S1d of the cut sheet S1 in the direction intersecting the conveyance direction with the leading edge S1a of the cut sheet S1 protruding from the base sheet 71. Therefore, after the user supplies the cut sheet S1 to the nip portion of the pair of conveying rollers 8 and 9, the user removes the rear end portion of the base sheet 71 from the guide sheet 30 and moves the auxiliary sheet 70 in the sheet conveying direction. It can be easily pulled out upstream. That is, the user can remove the paper feed auxiliary sheet 70 from the guide sheet 30 when the leading end of the cut sheet S1 reaches the nip portion of the pair of conveying rollers 8 and 9. Therefore, in a printer that fixes a print image formed on a cut sheet by a heating unit (a platen heater 15, a sheathed heater 16, etc.), the cut sheet S1 can be conveyed without blocking heat to the cut sheet S1.

S sheet S1 cut sheet 1 printer main body 3 image forming unit 8 transport roller 9 pinch roller 30 guide sheet (first sheet member)
70 Feeding auxiliary sheet (second sheet member)

Claims (6)

A cut sheet conveyance assisting tool used to assist conveyance of a rectangular cut sheet printed by an image forming apparatus,
A first sheet member configured to be attachable to the cut sheet;
A second sheet member configured to be attachable to both the first sheet member and the cut sheet;
The first sheet member is provided at an end portion of the first sheet member, and has an attachment portion to which the first edge of the cut sheet can be attached.
The second sheet member is
A third edge adjacent to the first edge and the second edge of the cut sheet, with the second edge opposite to the first edge of the cut sheet free. A gripping part for detachably gripping the edge and the fourth end edge;
A fixing portion that detachably fixes the second sheet member to the first sheet member,
Cut sheet conveyance aid. In the cut sheet conveyance auxiliary tool according to claim 1,
The cut sheet conveyance assisting device, wherein the attachment portion includes a clamping sheet portion that attracts the first sheet member by magnetism and clamps the first edge. In the cut sheet conveyance auxiliary tool according to claim 1,
The attachment part has a bonding surface formed on the first sheet member for bonding the first edge, and a cover sheet covering the bonding surface. In the cut sheet conveyance auxiliary tool according to any one of claims 1 to 3,
The cut sheet conveyance auxiliary tool, wherein the fixing portion attracts the first sheet member by magnetism. In the cut sheet conveyance auxiliary tool according to any one of claims 1 to 3,
The cut sheet conveyance assisting tool, wherein the fixing portion has an adhesive surface that adheres the second sheet member to the first sheet member. In the cut sheet conveyance auxiliary tool according to any one of claims 1 to 5,
The said holding | grip part has a notch | incision which each inserts said 3rd edge and said 4th edge formed in the said 2nd sheet member, The cut sheet conveyance assistance tool characterized by the above-mentioned.

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