JPH02282132A - Sheet conveyer - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is for use in, for example, medical image recording devices, reading devices, etc., for sequentially taking out and conveying sheets stored in a supply magazine one by one. The present invention relates to a sheet conveying device used for.

[Prior Art] As an example of a conventional device of this type, a sheet conveying device used in a medical image recording device will be described with reference to FIG. In FIG. 8, a supply magazine 2 loaded almost horizontally into an apparatus main body 1 stores a large number of unused recording sheets S, such as photosensitive films, in a stacked state. Among these sheets S, one of the uppermost sheets is sucked by a suction cup 4, and is inserted into a first sheet conveying means consisting of a belt 6 passed around three rollers 5 and a conveying roller 7, and is conveyed downward. It is designed to be transported by changing its direction. This sheet S turned downward
is conveyed further downward by a pair of conveying rollers 8, which is a second sheet conveying means, and a pair of sub-scanning rollers, which is a third sheet conveying means, and is finally stored in the receive magazine 10. However, along the way, main scanning is performed by the laser beam B that is irradiated onto a portion between the transport roller pair 8 and the sub-scanning roller pair 9 that is close to the sub-scanning roller pair 9. Note that guide plates (not shown) are arranged between the transport roller 7 and the transport roller pair 8 and between the transport roller pair 8 and the sub-scanning roller pair 9 at appropriate intervals on both sides of the transport path. Further, the distance between the pair of transport rollers 8 and the pair of sub-scanning rollers 9 is arranged shorter than the length of the sheet S to be used in the transport direction, and the leading edge of the sheet S transported by the pair of transport rollers 8 is placed between the pair of sub-scanning rollers. After the sheet S is sandwiched between the rollers 9 and 9, the rear end of the sheet S is separated from the pair of transport rollers 8. Even if the trailing edge of the sheet S separates from the pair of transport rollers 8,
The sheet S is held in a substantially vertical position by guide plates on both sides and is transported downward. In addition, 11 is an optical unit, which includes a laser light source and a polygon mirror etc. for scanning the laser beam B emitted from the laser light source, and the laser beam B emitted from this optical unit 71 is The light is reflected by the mirror 12 and main-scans the sheet S being transported downward in the vicinity of the pair of sub-scanning rollers 9 to record a predetermined image. A receive magazine 10 that receives recorded sheets S is installed at an angle of approximately 20 degrees from the vertical line, and its lid 10a can be opened and closed using the lower end of the receive magazine 10 as a fulcrum. This lid body 10a is automatically opened by a lid opening/closing mechanism (not shown) when the receive magazine 10 is loaded into the main body l of the apparatus, and when the receive magazine 10 is taken out, the stored recorded sheets S are exposed to light. The lid is automatically closed by the opening/closing mechanism to prevent it from happening. Furthermore, when the supply magazine 2 is loaded into the apparatus main body 1, it is loaded with the lid closed, and after this light is secured inside the apparatus main body 1, the lid is opened by a lid opening/closing mechanism (not shown). , the inner sheet S can be taken out. Note that 13 indicates a control unit containing a control circuit, a power supply, etc. for controlling the entire apparatus.

[Problems to be Solved by the Invention] In the conventional example described above, the length of the sheet S in the conveyance direction that can be stably conveyed is simply limited to l size.

If the length of the sheet S to be used in the conveyance direction is shorter than the appropriate length, the rear end of the sheet S will separate from the conveyance roller pair 8 before the leading edge of the sheet S is sandwiched between the sub-scanning roller pair 9. For.

The sheet S will fall freely without being restrained by the rollers. During this free fall, the sheet S becomes diagonal with respect to the conveyance direction, and there is a possibility that the main scan is performed diagonally with respect to the outer shape of the sheet S. For example, the rear end of the sheet S separates from the conveyance roller pair 8. In some cases, the front side and the back side of the rear end of the sheet S may not be separated at the same time. This can sometimes occur when the sheet S is conveyed at a slight angle or when the roller is bent. In such a case, if, for example, the rear end of the sheet S on the near side in the drawing leaves the conveyance roller pair 8 first, the sheet S moves toward the rear end of the sheet S due to its own weight. As a result, the leading end of the sheet S is conveyed with its back side in contact with the inside of 'Jtl, and not only is the recording diagonal, but also the stability of the conveyance speed is lost.

On the other hand, if the length of the sheet S used in the transport direction is longer than the appropriate length, recording may start before the trailing edge of the sheet S leaves the transport roller pair 8, and in this case, During recording, the rear end of the sheet S separates from the pair of transport rollers 8, and at that moment the load acting on the sheet S suddenly changes, causing the stability of the transport speed to be lost. As a result, a part of the scanning line interval, which must be constant over the entire area of the recorded sheet S, is disturbed. This is generally referred to as sub-scanning unevenness, and when recording is performed over the entire area of the sheet S with a laser beam B of a constant intensity, shading appears in some areas where the density should be constant, making it difficult to use. This results in harmful image quality deterioration. As described above, the conventional example has the disadvantage that it is not possible to stably convey sheets of a plurality of different sizes.

On the other hand, sheets of different sizes may be used in medical image recording equipment, etc., and sheet sizes include half-cut (approximately 35 x 43 cm) and large square (approximately 35 x 35 cm).
m), great circle (approximately 28 x 35 cm) 'J is commonly used. These sheets of different sizes are used depending on the number of formats for recording the parts to be recorded on one sheet, the modality to be connected to the recording device, the facility to be installed, the person using the sheet, etc.

SUMMARY OF THE INVENTION An object of the present invention is to provide a sheet conveying device that improves the drawbacks of the conventional example and enables stable sheet conveyance regardless of the size of the sheet used.

[Means for Solving the Problems] In order to achieve the above object, the sheet conveying device according to the present invention includes first, second, and third sheet conveying means from the upstream side in the sheet conveying direction. , in a sheet conveying device that performs recording or reading in the vicinity of the third sheet conveying means, the first and third sheet conveying means are fixed with respect to the sheet conveying direction, and the second sheet conveying means is not used. The distance of the conveying path between the second and third sheet conveying means is longer than the length of the sheet to be used in the conveying direction. It is characterized by being small and larger than the length of the recording or reading area of the sheet.

[Effect]

The sheet conveying device having the above configuration changes the position of the sheet conveying means of the PPJ2 so that the distance between the second and third sheet conveying means is shorter than the length of the sheet to be used in the conveying direction. Since it can be adjusted to be longer than the length of the area, even when using sheets of different sizes, the sheet being recorded or read is always restrained only by the pair of sub-scanning rollers, which is the third sheet conveyance means, and the sheet being recorded or read is There is no sudden load change on the seat inside the seat.
Stable sheet conveyance can be achieved by keeping the sheet conveyance speed constant.

[Example] The present invention will be explained in detail based on the example illustrated in FIGS. 1 to 7.

FIG. 1 shows an embodiment in which the present invention is applied to a medical image recording apparatus, and members that are the same as or equivalent to those of the conventional example shown in FIG. 8 are given the same reference numerals. Here, the difference from the conventional example shown in FIG. 8 is that when sheets of different sizes are used, the conveying roller pair 8, which is the second sheet conveying means, is indicated by a solid line according to the length of the sheet in the conveying direction. It is possible to change the position from the Ta position to the Tb or Tc position shown by the dotted line. The operation when the llff feed roller pair 8 is at the position Ta is the same as the conventional example shown in FIG. 8, so the explanation will be omitted here. The positional relationship between the roller pair 8 and the sub-scanning roller pair 9 will be explained with reference to FIG.

As described above, the distance L1 of the conveyance path between the pair of conveyance rollers 8 and the pair of sub-scanning rollers 9 is shorter than the length Fl of the sheet S to be used in the conveyance direction.

On the other hand, the distance L1 is longer than the length Pl of the recording area on the sheet S. That is, since the relationship Fl≧L1≧Pi exists, the leading edge of the sheet S conveyed downward by the pair of conveying rollers 8 is inserted into the pair of sub-scanning rollers 9 before the trailing edge leaves the pair of conveying rollers 9. Then, after the trailing edge of the sheet S leaves the pair of transport rollers 8, recording is started. With this configuration, the sheet S is always restrained by one of the roller pairs without freely falling until the recording is completed. Therefore, the sheet S becomes diagonal due to free fall, and main scanning is not performed diagonally with respect to the outline of the sheet S. Also, the only roller that is in contact with the sheet S during recording is the sub-scanning roller pair 9. , the leading edge of the sheet S may be inserted into another pair of rollers during recording,
Since the trailing edge of the sheet S does not separate from the other roller pairs, sudden load fluctuations do not occur on the sheet S during recording. Therefore, the conveyance speed of the sheet S becomes highly constant. Conveying speed unevenness, which causes image quality deterioration, is less likely to occur. The recording area on the sheet S is an area where stable recording can be performed, but if sub-scanning unevenness is not a problem, it is possible to print on areas other than the recording area, that is, the leading and trailing edges of the sheet S. For example, in this embodiment as well as in the conventional example, it is possible to irradiate the leading and trailing ends of the sheet S with a high-intensity recording beam and paint those parts black after development. This is because the pitch unevenness of the scanning lines is not noticeable in the blacked out areas.

This is because even if there is pitch unevenness, the purpose of blocking unnecessary light during image interpretation can be fully achieved. However, the lengths in the transport direction are F2 and F2, respectively.
3 and 4, a case where the sheet S of 3 (Fl>F2>F3) is used will be described.

FIG. 3 shows the case of conveying a sheet S whose length in the conveyance direction is F2. Here, the conveyance roller pair 8 is arranged at the position indicated by Tb, and therefore the conveyance roller pair 8 and the sub-scanning roller pair 9 are The distance L2 of the transport path is shorter than Ll in FIG. Furthermore, there is a relationship between this distance JIL2, the length F2 of the sheet S to be used in the transport direction, and the length F2 of the recording area of the sheet S, as shown in FIG. The same operation can be performed as in the case.

FIG. 4 shows a case where a sheet S whose length in the conveying direction is F3 is conveyed, and here the conveying roller pair 8 has changed to the position indicated by Tc. Also in this case, the distance of the transport path between the transport roller pair 8 and the sub-scanning roller pair 9 @L3, the length of the sheet S in the transport direction F3. It goes without saying that the relationship F3≧L3>F3 holds true with the recording area length F3 of the sheet S.

On the other hand, in FIGS. 2 to 4, the lowest roller of the three rollers 5 on which the belt 6 is passed and the conveyance roller 7 are shown.
The distance N of the transport path from the contact point with the sub-scanning roller pair 9 is constant. Therefore, the distance fiM1. of the conveyance path from the contact point position to the conveyance roller pair 8. Although M2 and M3 are different from each other, in order to carry out stable sheet conveyance during this period, it is desirable that the sheet S does not fall freely.
3. Here, since Fl>F2>F3, Ml>l'12>M3, so F3>M3
If the relationship holds true, then the relationships Fl>Ml and F2>M2 naturally hold true.

Therefore, if the configuration is such that F3>83, stable sheet conveyance becomes possible.
If great circle size sheets S are used, the length of each of these sheets S in the transport direction is F1 = 430 m.
m, F2=354mm, F3=279mm. Furthermore, if the length Pl of the recording area of the half-cut size sheet S is set to 400 mm, and if F2 in FIG. 2 (7) is set to 420 mm, the relationship Fl≧Ll<PI can be satisfied. Similarly, in the case of large angle and great circle sizes, F2≧L2>F2 and F3≧L3>F3 can be set, respectively.

On the other hand, if Fig. 4 (7) M3 is 270 mm, then F3>
The condition of M3 can be satisfied. In this case, Ml in FIG. 2 will be approximately 120 mm, and all mechanisms can be arranged without difficulty.

Figure 5 shows the conveyor roller pair 8 as shown in Figure 1, ↑a, Tb, T.
FIG. 6 is a side view of a specific mechanism for selectively arranging the device at one of the positions indicated by c. The three rollers 5 on which the belt 6 is hung are attached to the frame 21 of the device.
The transport roller 7 is also rotatably attached to the frame 21 via a shaft 22 . Further, another sub-frame 24 is removably fixed to the frame 21 with mounting screws 25, and two rollers 8a and 8b constituting the transport roller pair 8 are attached to this sub-frame 24. The roller 8b is attached to a lever 27 that is rotatable around an axis 26 with respect to the subframe 24, and is attached to the drive side roller 8a by a spring 28 hung between the lever 27 and the subframe 24. Forced. A sprocket 30 is attached to the shaft 29 of the roller 8a, and a sprocket 31 is also fixed to the shaft 23 of the conveying roller 7. Further, an idler sprocket 32 is arranged at an intermediate position between these tin rockets 30 and 31, and this idler sprocket 32 is rotatably held by the frame 21 via a shaft 33. A sprocket 36 is attached to the shaft 35 of the electric @ 34 that drives the conveyance roller 7 and the roller 8a, and a chain 37 is stretched from the sprocket 36 to the sprockets 31, 32, and 30. Here, the sprockets 30, 31 are selected so that the outer peripheral speeds of the roller 8a and the conveyance roller 7 are the same. The frame 21 is paired with another frame (not shown) having a substantially symmetrical shape, and the two are connected by a coupling member while facing each other, with a shaft 22.2.
3 and the other end side of the subframe 24, which is not shown in FIG. 6, is held by the aforementioned frame (not shown).

Further, the frame 21 and the above-mentioned frame (not shown) facing the frame 21 are provided with a square hole 38 for enabling movement of the pair of conveyance rollers 8, and the pair of conveyance rollers 8 are provided on both sides of the square hole 38. Attachment holes 39a for fixing the subframe 24 so that it can be placed at each position of Ta, Tb, and Tc shown in FIG.

39b and 39c (however, 39a is not shown during use) are open. The electric motor 34 is fixed to the frame 21 with mounting screws 40, and the mounting hole 41 is a long hole so that the position of the electric motor 34 can be adjusted to a certain degree. The pair of sub-scanning rollers 9 shown in FIG.
It is possible to set the outer peripheral speeds of the roller 8a driven by the sub-scanning roller pair 9 to be different from that of the sub-scanning roller pair 9 driven by the sub-scanning-dedicated electric motor. However, when the same sheet S is simultaneously pinched by at least the pair of sub-scanning rollers 9 and the pair of transport rollers 8, the outer peripheral speeds of both pairs of rollers 8.9 are set to be substantially concave.

5 and 6 show the conveyor roller pair 8 set at position Ta in FIG. 1, but when setting it at position Tb or Tc, first attach Loosen the motor 34 to make it movable along the mounting hole 41, and release the tension on the chain 37. Next, loosen the mounting screw 2.
5 and move the subframe 24 downward together with the pair of transport rollers 8.

If the subframe 24 is fixed by replacing the mounting screws 25 in the mounting holes 39b or 39c, the conveyance roller pair 8
It is placed at the position Tb or Tc shown in the figure. In this case, the sprocket 30 is at the 30' or 30'' position shown by the dotted line, and the chain 37 is also at the 37° or 37'' position. Thereafter, the electric motor 34 may be fixed at a position that applies appropriate tension to the sprocket 30.

In the embodiments shown in FIGS. 5 and 6, the conveyance roller pair 8 is formed into a unit by the subframe 24, and its position is changed together with the subframe 24, so that the same chain 37 can be used. It is also possible to omit the sub-frame 24 and attach the pair of conveyor rollers 8 directly to the frame 21. For example, as shown in FIG. ! J
Chains 42°4 are provided at three locations corresponding to the positions of Ta, Tb, and Tc shown in the figure, and have different lengths depending on each position.
2' or 42'' may be used.

In FIG. 7, holes 43, 44, 45.
46, holes 43', 44',
45', 46°, and holes 43'' at positions corresponding to Tc.
, 44'', 45'', and 46'', respectively.

Here, the holes 43, 43', 43'' are the shaft 2 of the roller 8a.
The holes 44.44' and 44'' are holes for passing the shaft of the roller 8b, the holes 45.45'' and 45'' are holes for passing the shaft 26 through, and the holes 46.46' and 46'' are holes for the spring 28 to pass through. It shows the hole for hanging. When the transport roller pair 8 is placed at the position Ta in FIG. 1, that is, the position shown in FIG. 7, using these three stages of mounting holes, the sprocket 36.
31. The shortest chain 42 is used to hang the chain 30, and the pair of conveyor rollers 8 are connected to Tb or T as shown in FIG.
When placed at the position corresponding to c, sprocket 3
Since the 0 positions are the positions indicated by 30' and 30'', the chains 42' and 42'' used are also of different lengths. In this case, the fifth
Since the subframe 24, idler sprocket 32, etc. shown in FIGS.

As is clear from the above embodiments, the present invention can be applied to sheets S of various sizes by changing the position of the conveying roller pair 8.
The mechanism itself for changing the position of can be modified in various ways.For example, the pair of conveyor rollers 8 may be individually provided so as to move forward and backward at each position of Ta-Tc in FIG. The other two sets may be moved forward into the sheet transport path, while the other two sets are retracted from the sheet transport path. In this case, the size of the sheet S to be used is detected and the optimal transport roller pair 8 is automatically selected. It is also possible to advance into the sheet conveyance path and keep the conveyance roller pair 8 always installed in the sheet conveyance path unless the size of the sheet s is changed. Further, the pair of conveyance rollers 8 may be configured to be able to change their positions automatically, and these changes may be made manually or automatically by detecting the size of the sheet S. .

In the above-described embodiment, the conveyance roller pair 8 is arranged at three locations Ta to C, but the locations are not limited to three and may be at a plurality of locations.

Note that the conveying direction of the sheet S is not limited to the vertical direction, but may be horizontal or diagonal, the conveying path of the sheet S may not be a straight line but a curved line, and the sheet conveying means is not necessarily The present invention is not limited to a pair of rollers, and may be replaced with other means such as a lever. Needless to say, the present invention can be applied not only to the LT system but also to image reading apparatuses.

[Effects of the Invention] As explained above, the sheet conveying device according to the present invention can always maintain stability even when sheets of different sizes are used by simply changing the position of the second sheet conveying means. This method has the advantage that it is possible to convey the sheet in a controlled manner.

[Brief explanation of drawings]

1 to 7 show an embodiment of a sheet conveying device according to the present invention, FIG. 1 is a block diagram of an embodiment in which the present invention is applied to a medical image recording device, and FIGS. 2 to 4 is a configuration diagram of the positional relationship between the second and third sheet conveyance means, FIG. 5 is a configuration diagram of the position movement mechanism of the second sheet conveyance means, FIG. 6 is a side view thereof, and FIG. 7 is a configuration diagram of the position movement mechanism of the second sheet conveyance means. This is a configuration diagram of another example of
FIG. 8 is a configuration diagram of a conventional example. Symbol l is the main body of the device, 2 is a supply magazine, 8 is a pair of transport rollers, 9 is a pair of sub-scanning rollers, 10 is a receive magazine, 11 is an optical unit, 21 is a frame, 24 is a subframe, and 25 is a mounting screw. , 30.31.32.3
6 is the sprocket. 34 is an electric motor, 37 is a chain, and 38 is a square hole. Figure 1 Patent applicant Canon Co., Ltd. Figure 2 Figure 3 Figure 6 Figure M4 Figure 5 Figure 71! I

Claims (1)

[Claims] 1. A sheet conveying device that has first, second, and third sheet conveying means from the upstream side in the sheet conveying direction, and performs recording or reading in the vicinity of the third sheet conveying means,
The first and third sheet conveyance means are fixed with respect to the sheet conveyance direction, and the second sheet conveyance means is movable in the sheet conveyance direction in accordance with the length of the sheet to be used in the conveyance direction. , wherein the distance of the conveying path between the second and third sheet conveying means is smaller than the length of the sheet used in the conveying direction and larger than the length of the recording or reading area of the sheet. Conveyance device.