JP2006082916A - Sheet loading device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a detection means capable of detecting a rear end curl or the like of a sheet regardless of a sheet size in a sheet loading device provided with a sheet loading part; and the detection means for abutting on an upper surface of a bundle of sheets loaded on the sheet loading part and detecting height of the bundle of the sheets. <P>SOLUTION: The detection means comprises a pivoting member 10 having a distal end contacting an upper part of the bundle of the sheet and pivoted making a shaft 13 as a center and provided with a pivot angle detection means on the shaft 13. The detection means is provided with a plurality of detection parts 11, 21 having different detection height. Detection positions 12, 22 of the upper surface of the bundle of the sheet of a plurality of detection parts 11, 21 are set to the approximately same distance from a tail end of the sheet respectively. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a sheet stacking apparatus provided with a detecting unit for detecting a stacking state of sheet bundles on a sheet discharge tray in an image forming apparatus and other sheet discharge apparatuses.

  2. Description of the Related Art A sheet stacking device in a paper discharge device such as a copying machine, a facsimile machine, or a printer is provided with a detecting unit that detects when a sheet is full.

  As such a full load detection means, conventionally, for example, a swingable detection lever that contacts the upper surface of the tail end side of the sheet is used, and the detection height contacts the upper surface of the central portion in the width direction of the sheet. An image forming apparatus has been proposed that is lower than the detection height of the sheet, realizes reliable full-load detection even when the size and type of the sheet changes, and enables good sheet discharge and stacking processing. (For example, refer to Patent Document 1).

  With this technique, the position of the detection lever that contacts the sheet differs depending on the size of the sheet in the sheet discharge direction, and thus the trailing edge curl of the sheet may not be detected.

  There is also known a detection means that can adjust the full detection height of the sheet. (For example, refer to Patent Document 2).

In this technique, a detection unit for detecting the fullness of a sheet is attached to a swing device in a variable connection position.
Japanese Unexamined Patent Publication No. 2003-48644 (page 2-5, FIG. 2) JP 2003-137479 A (page 2-3, FIG. 1)

  SUMMARY OF THE INVENTION An object of the present invention is to provide a sheet stacking apparatus including a detecting unit that can detect a trailing edge curl of a sheet regardless of the sheet size.

  The present invention has been made to solve the above problems, and is a sheet stacking apparatus characterized by taking the following technical means.

  That is, the present invention provides a sheet having a sheet stacking unit on which discharged sheets are stacked, and a detection unit that detects the height of the sheet bundle in contact with the upper surface of the sheet stack stacked on the sheet stacking unit. In the stacking apparatus, the detection means is composed of a swinging member having a tip end side that is in contact with the sheet bundle and swinging, and a swinging angle detecting unit is provided on the base side. The swinging member has a plurality of detection heights. The sheet stacking apparatus includes a detection unit, and the detection positions on the upper surface of the sheet bundle of the plurality of detection units are set substantially at the same distance from the tail end of the sheet.

In the present invention, sheet fullness detection means having different detection heights according to the sheet size are provided so that the distances from the sheet edge to the detection position are substantially the same. Accordingly, there is no variation in the detection position, and the sheet height can be detected without being affected by the curl of the sheet edge.

  The plurality of detection units may have different inclination angles with respect to the sheet discharge direction. Since the configuration of the present invention is made possible by making the inclination angle of the detection member different, it is simple.

  In addition, it is preferable that the plurality of detection units have substantially the same inclination angle with respect to the sheet discharge direction and are arranged vertically in a substantially vertical direction on the upper surface of the sheet bundle. According to this configuration, the inclination angle of the detection member is substantially constant, and the configuration of the present invention is made possible by offsetting. The collision angle of the sheet to the detection member becomes substantially constant, and the sheet can be discharged stably. In this case, each of the detection means having different detection heights according to the sheet size can detect the sheet height without being affected by the curl or the like of the sheet end portion having the substantially same distance from the sheet end portion to the detection position.

  Further, if the plurality of detection units have a detection area having a constant width in the sheet width direction, detection can be performed according to the width dimension of the sheet, and detection is possible even when the sheet is displaced in the width direction. Yes, it is preferred.

  In addition, when the detection unit having a low detection height among the plurality of detection units is disposed closer to the side end portion of the sheet than the detection unit having a high detection height, a detection sheet having a narrow width is detected. It can be detected by a high detection unit. According to this configuration, it is possible to reduce the stacking height of large sized sheets with a large curl amount and increase the stacking height of small sized sheets with a relatively small curl amount.

  When at least one of the plurality of detection units is provided at a position corresponding to the tail end of each of a plurality of size sheets that can be stacked on the sheet stacking unit, the side edge curl of the sheet is appropriately Can be detected. In addition, when at least some of the plurality of detection units are integrally formed, the rigidity of the detection member increases and the manufacture becomes easy. At least one of the plurality of detection units can change the detection height according to the curl amount and type of the sheet if the detection height is variable and the height is adjustable. The detection height can be effectively changed in accordance with the actual condition of the state, which is preferable.

  In addition, if at least one of the plurality of detection units makes the inclination angle variable, the detection height can be easily changed by simply changing the angle of the detection member.

  Furthermore, if at least one of the plurality of detection units has a variable vertical distance, that is, an offset amount, the detection height is changed by changing the offset amount of the detection member, so that the detection position is shifted. There is no.

  Note that the height of the detection unit varies depending on the sheet size, stiffness, etc., so the optimum height varies depending on each sheet. Thus, the height of the detection unit can be substantially optimized. In addition, even if the moisture content of the sheet varies depending on the usage environment and the curl amount changes from the expected value, or when an unexpected sheet is used, optimization is appropriately performed by changing the height of the detection unit. be able to.

  Since the present invention is a sheet full detection unit whose detection height varies depending on the sheet size and the distance from the sheet edge to the detection position is substantially the same, there is no variation in the detection value and the sheet edge is not affected by the curl. The seat height can be detected.

  Embodiments of the present invention will be described below with reference to the drawings.

  First, the prior art will be described with reference to FIGS. FIG. 11 is a perspective view showing a conventional rocking member (sheet detecting means) 50. The swing member 50 swings around the shaft 55 as indicated by an arrow 56. As shown in FIG. 12, the height detection unit 51 on both ends detects the height of the sheet bundle 31 by the detection end 52 coming into contact with the upper surface of the wide sheet bundle 31, and the height detection unit 53 on the center side The detection end 54 contacts the upper surface of the narrow sheet bundle 32 to detect the height of the sheet bundle 32.

  FIG. 12 is a side view showing the operation of the detection unit. The detection unit 51 has a length dimension a, and the detection unit 53 has a length dimension b. The positions in contact with the upper surfaces of the sheet bundles 31 and 32 are values different from the distances A and B from the sheet ends, respectively. If curl or the like occurs in the sheet bundles 31, 32, the sheet height detection becomes inaccurate, and in some cases, cannot be detected.

  FIG. 1 is a perspective view showing an example of a swing member 10 that is a sheet detection of a sheet stacking apparatus according to the present invention. The swing member (sheet detection means) 10 of the present invention includes detecting units 11 and 21 that swing around a shaft 13 and swing. In FIG. 1, two examples of the swing member 10 divided into left and right are shown, but they may be integrated or further divided into a large number. The detection ends 12 and 22 at the leading ends of the swinging detection units 11 and 21 are in contact with the upper surface of the sheet bundle stacked on the sheet stacking unit. The height of the contact is detected by a swing angle detecting means such as an angle meter (not shown) attached to the shaft 13.

  The swinging member 10 of the present invention includes detection units 11 and 21 having different detection heights, and the detection end 12 of the detection unit 11 is in contact with a wide sheet bundle to detect the height thereof. The detection end 22 of the detection unit 21 comes into contact with a narrow sheet bundle and detects its height. In the present invention, the detection ends 12 and 22 in contact with the upper surface of the sheet bundle of the detection units 11 and 21 are set to be substantially the same distance from the tail end of the sheet width.

  FIG. 2 is a longitudinal sectional view of the sheet stacking tray 30 for explaining this operation. The swing member (sheet detection means) 10 includes detection units 11 and 21 having different height positions. The detection end 12 contacts the upper surface of the sheet bundle 31 of the detection unit 11 and the sheet bundle 32 of the detection unit 21. The detection end 22 in contact with the upper surface of the sheet bundle 31 is located at a substantially same distance A from the tail ends 33 of the sheet bundles 31 and 32.

  Incidentally, in the swing member 50 of the prior art shown in FIG. 11, the detection unit 51 in contact with the wide sheet bundle and the detection unit 53 in contact with the narrow sheet width are in the same height plane. , 53 are the lengths indicated by a and b in FIG. 2, and the detection end 54 where the detection unit 53 contacts the upper surface of the sheet width 32 is a distance A from the tail end of the detection end 52 of the detection unit 51. Unlike the case, the distance B is from the tail end of the sheet.

  In the present invention, the detection end 12 of the detection unit 11 in contact with the upper surface of the wide sheet bundle 31 and the detection end 22 of the detection unit 21 in contact with the upper surface of the narrow sheet width 32 are substantially the same distance A from the tail end of the sheet bundle. Since the size of the detection unit 21 is determined so that the detection position does not vary, the height of the sheet bundle can be detected without any influence even if the detection end has a curl and the end of the sheet is curled.

  FIG. 3 shows a side sectional view of another detection means 10 of the present invention, which is an example having detection portions 11 and 21 that swing around an axis 13 and have different angles α and β. Also in this case, the detection ends 12 and 22 in contact with the upper surfaces of the sheet bundles 31 and 32 are set to an approximately equal distance from the tail end of the sheet bundle.

  FIG. 4 is a perspective view of the sheet stacking unit 30 and shows an example in which the swinging member (sheet detection means) 10 is separated from the left and right detection units 11 and the central detection unit 21. FIG. 5 shows an example in which the detection portions 11 and 21 of the swing member (sheet detection means) 10 are an integral assembly wall.

  FIG. 6 is an example in which the movable member 25 is provided on the bracket 26 so that the swinging member 10 having the detection units 11 and 21 having different heights can change the angle and the height position.

  FIG. 7 shows an example of a support mechanism for the swing members 11 and 12 having a higher degree of freedom and adjustable angle, and shows a mechanism in which links 23 and 24 having pin joints that are rotatable at both ends are connected. ing.

  FIG. 8 shows an example in which the shaft 13 and the swinging member 10 are coupled by changing the angle by the surface clutch 40. FIG. 8 shows an example of a means for adjusting the angle of the swing member (sheet detecting means) 10. The surface clutch 40 is interposed between the shaft 13 and the swing member 10, and the swing member 10 is indicated by an arrow. The installation angle can be freely changed and adjusted by rotating as shown by 42 and shifting the shaft 13 as shown by the arrow 41 and joining the shaft 13 and the swing member 10 with the surface clutch 40.

  These are merely examples, and other known means such as other groove cams can be used.

  FIG. 9 shows an example of means for changing the height-direction dimensions of the detecting portions 11 and 12 of the swing member (sheet detecting means) 10. One member is provided with a slit 27, and the slit 27 is provided on the other side. This is an example in which a screw 16 to be fixed to the head can be inserted and combined at an arbitrary position. Instead of slits, long holes or multiple round holes may be provided.

  In FIG. 10, a rising portion 17 is provided on one member, a number of slits 18 are provided in a step shape in the height direction, and the other detection portion 21 is inserted into the slit 18 as indicated by an arrow 29. Means are shown. 9 and 10 are exemplifications, and various other known height difference changing techniques can be used.

It is a perspective view of the sheet | seat detection means of an Example. It is operation | movement explanatory drawing of an Example. It is a side view which shows the Example from which an angle differs. It is a perspective view which shows the isolate | separated Example. It is a perspective view which shows the Example made into the integral assembly type. It is explanatory drawing which shows the example of an angle adjustment means. It is explanatory drawing which shows the example of an angle adjustment means. It is explanatory drawing which shows the example of an angle adjustment means. It is explanatory drawing which shows the example of a height adjustment means. It is explanatory drawing which shows the example of a height adjustment means. It is a perspective view of a prior art example. It is operation | movement explanatory drawing of a prior art example.

Explanation of symbols

10 Swing member (sheet detection means)
DESCRIPTION OF SYMBOLS 11, 21 Detecting part 12, 22 Detecting end 13 Axis 16 Screw 17 Rising part 18 Slit 23, 24 Link 25 Movable member 26 Bracket 27 Long hole or slit 29 Arrow 30 Sheet stacking tray 31, 32 Sheet bundle 33 Tail end 40 Surface clutch 41, 42 Arrow 50 Oscillating member (sheet detecting means)
51, 53 Detector 52, 54 Detection end 55 Axis 56 Arrow

Claims (10)

In a sheet stacking apparatus comprising: a sheet stacking unit on which discharged sheets are stacked; and a detection unit that detects the height of the sheet bundle by contacting an upper surface of the sheet stack stacked on the sheet stacking unit.
The detection means is composed of a rocking member having a tip side in contact with the sheet bundle and rocking, and a rocking angle detecting means on the base side, and the rocking member has a plurality of detecting parts having different detection heights. In addition, the sheet stacking apparatus is characterized in that the detection positions on the upper surface of the sheet bundle of the plurality of detection units are set at substantially the same distance from the tail end of the sheet.   The sheet stacking apparatus according to claim 1, wherein the plurality of detection units have different inclination angles with respect to the sheet discharge direction.   2. The plurality of detectors according to claim 1, wherein the plurality of detectors have substantially the same inclination angle with respect to the sheet discharge direction, and are arranged vertically in a substantially vertical direction on the upper surface of the sheet bundle. Sheet stacking device.   The sheet stacking apparatus according to claim 1, wherein the plurality of detection units have a detectable area having a constant width in the sheet width direction.   The detection unit having a low detection height among the plurality of detection units is arranged closer to the side edge of the sheet than the detection unit having a high detection height. The sheet stacking apparatus described in 1.   2. The at least one of the plurality of detection units is provided at a position corresponding to each tail end of a plurality of size sheets that can be stacked on the sheet stacking unit. The sheet stacking apparatus according to any one of?   The sheet stacking apparatus according to claim 1, wherein at least some of the plurality of detection units are integrally formed.   The sheet stacking apparatus according to claim 1, wherein the detection height of at least one of the plurality of detection units is variable.   The sheet stacking apparatus according to claim 2, wherein the inclination angle of at least one of the plurality of detection units is variable.   The sheet stacking apparatus according to claim 3, wherein at least one of the plurality of detection units has a variable vertical height position.

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