JPH0516322U - Paper feed mechanism of ink jet printer - Google Patents

Abstract

(57) [Summary] [Purpose] To ensure a uniform printing interval between the inkjet head and the paper. [Structure] A paper guide 10 is supported between the first and second conveying rollers 5 and 7 so that a supporting surface 10d thereof and outer peripheral surfaces 5a and 7a of the first and second conveying rollers 5 and 7 coincide with each other. Supported by erection. As a result, no inclined portion is formed on the support surface 10d, and the print interval between the inkjet head 1 and the paper P can be ensured uniformly.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a paper feed mechanism of an ink jet printer that prints and prints on paper by inkjet.

[0002]

[Prior Art]

 The inventor of the present application has already proposed the one shown in FIG. 4 as a paper feeding mechanism of an ink jet printer installed in a facsimile machine or the like. In this inkjet printer, the first conveying roller 32 is arranged upstream of the paper passage 31 immediately before the printing range E of the ink jet head 30 for printing and printing image information on the paper P (hereinafter referred to as printing). In addition, a pressing plate 33 that presses the first transport roller 32 is disposed on the upstream side of the inkjet head 30. On the other hand, on the downstream side of the ink jet head 30, a second conveying roller 34 and a pressing roller 35 having a large number of saw-tooth-shaped projections are arranged so as to come into contact with each other. Further, a paper support 36 is arranged at a position facing the ink jet head 30. Then, the paper P fed between the first conveying roller 32 and the holding plate 33 is fed onto the paper support 36 while being pressed by the holding plate 33 by the rotation of the first feeding roller 32. Then, printing is performed in the printing range E of the inkjet head 30. Thereafter, the printed paper P is discharged to the outside of the inkjet printer while being pressed by the pressing roller 35 by the rotation of the second transport roller 34.

[0003]

[Problems to be solved by the device]

 However, in the above-described paper feeding mechanism of the ink jet printer, the first feeding roller 32 provided immediately before the printing range E of the ink jet head 30 provides feeding until just before the end of the paper, so that the feeding force can be increased. The inkjet head 30 and the paper support 36 are excellent in that the print quality can be maintained high regardless of the conveyance force between the second conveyance roller 34 and the pressing roller 35. The problem that it is not possible to secure a uniform print interval has not been solved regardless of the position of the first transport roller 32. That is, in an inkjet printer, good printing quality cannot be obtained unless the printing interval between the inkjet head 30 and the paper P is set to 1.0 ± 0.1 mm. The flatness is cut to ± 0.1 mm or less, and the paper support 36 is manually attached to the frame by using a dedicated jig so that the printing interval is within the above range. Was there.

However, the shape of the paper support 36 is such that the upstream portion 36 a of the support surface is formed to incline downward to prevent paper jam when the paper P enters the paper support 36. Therefore, when the leading edge and the trailing edge of the paper P pass through the upstream portion 36a, the paper P hangs down, and there is a problem that the printing interval cannot be secured.

An object of the present invention is to provide a paper feeding mechanism for an inkjet printer that can ensure a uniform printing interval between the inkjet head and the paper.

[0006]

[Means for Solving the Problems]

 In order to solve the above problems, the present invention conveys a sheet onto a sheet support by a first transport unit, prints on the sheet with an inkjet head on the sheet support, and then transfers the sheet to the downstream side of the inkjet head. In the paper feeding mechanism of the ink jet printer which is configured to discharge by the second transport unit, the support surface of the paper support is aligned between the first and second transport units so that the transport surface is aligned with each transport site. The main idea is to support the installation.

[0007]

[Action]

 According to the present invention having such a configuration, since the conveying portions of the first and second conveying portions and the supporting surface of the paper support are erected and supported, an inclined portion is formed on the supporting surface. Therefore, it is possible to secure a uniform print interval between the inkjet head and the paper.

[0008]

【Example】

 An embodiment in which the present invention is embodied in an inkjet printer will be described below with reference to FIGS.

As shown in FIGS. 1 and 2, the inkjet head 1 is arranged so as to face the paper path 2 of the paper P provided in the inkjet printer M, and is moved in a direction crossing the passing paper surface by a scanning mechanism (not shown). It is possible. A print area E is provided on the surface of the ink jet head 1 facing the paper passage 2, and ink is ejected by a nozzle (not shown) within this print area to print on the paper P. In the vicinity of the printing range E, a rotating shaft 4 is inserted and supported by the frame 3 on the upstream side of the paper passage 2. Then, on this rotating shaft 4, first conveying rollers 5 (three in this case) as divided first conveying portions are axially mounted at equal intervals. On the other hand, a rotary shaft 6 is inserted and supported by the frame body 3 on the downstream side of the inkjet head 1 so as to be parallel to the rotary shaft 4. Then, a second conveying roller 7 (three in this case) as a second conveying portion that is divided and formed on the rotating shaft 6 is axially mounted at a position corresponding to the first conveying roller 5. . Further, cylindrical bearings 8 and 9 are rotatably fitted (in this case, four in each case) to the non-axially attached portions of the first and second conveying rollers 5 and 7 of the rotary shafts 4 and 6. Each of the bearings 8 and 9 is provided with a paper guide 10 as a paper support (in this case, four guides).

As shown in FIG. 3, the paper guide 10 is composed of a rectangular parallelepiped substrate 10a and semi-cylindrical engagement portions 10b formed on both end faces of the base plate 10a in the width direction. There is. Further, an engaging groove 10c engaging with the bearings 8 and 9 is formed in a lateral U-shape from both ends in the width direction of the paper guide 10 to a part of the engaging portion 10b and the substrate 10a. . Further, a supporting surface 10d is formed on the upper surface of the substrate 10a so that the flatness is ± 0.1 mm or less.

As shown in FIG. 1, when the bearings 8 and 9 and the engagement groove 10c of the paper guide 10 are engaged with each other, the support surface 10d of the paper guide 10 and the first and second conveyance rollers are engaged. The outer peripheral surfaces 5a and 7a, which are the transporting portions of 5 and 7, are on the same line. Further, the printing interval between the inkjet head 1 and the paper P conveyed onto the paper guide 10 is 1.0 ± 0.1 mm.

As shown in FIGS. 1 and 2, an elastic holding plate 11 for pressing the first conveying roller 5 is bolted to the frame 3 on the upstream side of the inkjet head 1. Due to the elasticity of the pressing plate 11, the pressing plate 11 is constantly pressed against the first conveying roller 5 side. A rotary shaft 12 is rotatably inserted into and supported by the frame 3 above the second transport roller 7, and the rotary shaft 12 has a plurality of saw-toothed presser projections 13a. The roller 13 is mounted on the shaft. The pressing roller 13 is constantly biased toward the second conveying roller 7 by a spring (not shown). Further, paper guides 14, 15 are fixed to the frame 3 with the first and second conveying rollers 5, 7 interposed therebetween. Further, pulleys 16 and 17 are fixed to one ends of the rotating shafts 4 and 6. A belt 19 is stretched between the pulleys 16 and 17 and the driving roller 18 a of the motor 18. Then, when the motor 18 is driven, the first and second transport rollers 5, 7 rotate in the same direction.

Next, the operation of the inkjet printer M configured as described above will be described. The paper P fed between the first conveying roller 5 and the holding plate 11 is pressed by the holding plate 11 and is fed by the rotation of the first roller 5 driven by the motor 18. The paper P passes through the engaging portion 10b of the paper guide 10 and is fed onto the substrate 10a while maintaining a constant print interval. Then, the ink is ejected onto the paper P in the printing range E of the inkjet head 1 to perform printing. After that, the paper P passing between the inkjet head 1 and the paper guide 10 is discharged to the outside of the ink jet printer M while being pressed by the pressing roller 13 by the rotation of the second transport roller 7.

As described above, in the paper feeding mechanism of the inkjet printer according to the present embodiment, the bearings 8 and 9 are fitted to the non-axially attached portions of the first and second conveying rollers 5 and 7 of the rotating shafts 4 and 6, respectively. By mounting the paper guide 10 on both bearings 8 and 9 so that the supporting surface 10d and the outer peripheral surfaces 5a and 7a of the first and second transport rollers 5 and 7 are aligned with each other, the paper P The leading and trailing edges of the paper P do not hang down during transportation, and the printing interval can be kept uniform.

Further, since the shape of the engaging portion 10b of the paper guide 10 is the shape along the outer peripheral surfaces 5a and 7a of the first and second conveying rollers 5 and 7, the paper P is guided to the paper guide 10. There is no paper jam even when entering.

Further, when assembling the paper guide 10, since the assembling position is determined by the rotary shafts 4, 6 and the bearings 8, 9, it is necessary to secure a printing interval by using a dedicated jig. It is not necessary and can be easily assembled.

It should be noted that the present invention is not limited to the above-described embodiment. For example, in the above-described embodiment, the first transport roller 5 is arranged immediately before the printing range E, and is provided on the upstream side of the inkjet head 1. Although the holding plate 11 is arranged, instead of this, a conveying roller and a driven roller are arranged on the upstream side of the ink jet head 1 with the paper passage 2 interposed therebetween, and the conveying roller and the second conveying roller 7 are connected to each other. The sheet guide 10 may be installed between the sheets to convey the sheet P.

[0018]

[Effect of the device]

 As described above in detail, according to the paper feeding mechanism of the inkjet printer of the present invention, the excellent effect that the printing interval between the inkjet head and the paper can be uniformly ensured is obtained.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view showing an inkjet printer of the present invention.

FIG. 2 is a bottom view showing the same inkjet printer.

FIG. 3 is a perspective view showing a paper guide of a paper feeding mechanism of the inkjet printer.

FIG. 4 is a schematic cross-sectional view showing a conventional inkjet printer.

[Explanation of symbols]

1 inkjet head, 5 first transport roller, 5
a, 7a Peripheral surface as a transportation part, 7 Second transportation roller, 10 Paper guide as a paper support, 10d
Support surface, 11 pressing plate, 13 pressing roller, P paper.

Claims (1)

[Scope of utility model registration request] 1. A paper is fed onto a paper support by a first transport unit, printed on the paper by an inkjet head on the paper support, and then discharged by a second transport unit downstream of the inkjet head. In the paper feed mechanism of the inkjet printer, the paper support is erected and supported between the first and second transport units so that the support surface of the paper support is aligned with each transport site. Paper feed mechanism for inkjet printers.