JPS6216432Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a support structure for a paper separation claw in an automatic paper feeder of a printing device used in an information processing system.

One of the widely used automatic paper feeding devices is one in which media sheets are stacked on a hopper table that moves up and down, and the media sheets are fed by a pick crawler that rotates in contact with the top surface of the media sheets. A device is known in which a separation claw is used that engages both corners of the leading edge of the media sheet in order to separate the media sheets one by one. The action of this separation claw is extremely delicate, and normally this separation claw is supported in a floating state by a lower moving member, and there is no problem when the hopper stand moves up and down in parallel, but the lifting and lowering structure of the hopper stand When a structure in which the hopper table rotates to move up and down is adopted in order to simplify the process, there was a problem in that the function of the separating claws was not fully exerted in the conventional support structure. In other words, as shown in FIG.
If the structure is such that the upper end and the lower part of a are inserted into the through holes 5 and 6 provided in the sliding member 4 and supported in a floating state, the medium paper is inserted as shown in FIGS. When the loading amount of the media sheet 7 changes, the contact angle between the media sheet 7 and the separation claw 3 changes, and in the state shown in the second figure where the loading amount of the media sheet 7 is large, it becomes difficult for the media sheet 7 to separate from the separation claw 3. Therefore, paper feeding errors are likely to occur, and in the state shown in the third figure where the amount of loaded media sheets 7 is small, the media sheets 7 are likely to separate from the separation claws 3, causing the problem that two sheets of paper are more likely to be fed. Ta.

In FIG. 1, reference numeral 8 denotes a friction roller device that grips and drives the supplied medium paper, 9 a printing head, 10 an anvil, 11 a medium guide plate, 1
2 is a presser plate that presses the leading edge of the medium paper 7;
3 is a pick crawler; 14 is a hopper table elevating device; the medium guide plate 11 and the presser plate 12 are made of bent plate material and are integrally formed with the stationary member 4; the pick crawler 13 is pivoted to the stationary member (not shown). The hopper table elevating device 14 has a drive pulley 17 and a driven pulley 18 that are pivotally supported on a stationary member (not shown). The locking piece fixed to the belt 19 wound between the hopper stand 1
The hopper table 1 is rotated up and down around the pivot pin 2 by rotating the drive pulley 17 by an electric motor (not shown).

This invention was made with the aim of solving the above-mentioned problem that occurs when the hopper table is rotated and raised and lowered, and even if the loaded amount of media sheets changes, the media sheets and separation claws are not easily separated. To provide a support structure for a separating claw that can reliably separate and supply paper irrespective of the amount of media by preventing the contact angle from changing.

That is, the support structure of the paper separation claw of this invention is such that the medium paper 7 on the hopper table 1 which rotates and rises and falls is picked up in one go.
The support structure of the paper separation claw 3 that separates one sheet at a time is a separation claw 3 having a support rod portion 3a extending downward.
The upper end of the support rod portion 3a is supported by a frame or other lower moving member 4 so as to be rotatable and movable up and down, and is connected below the support rod portion 3a to a hopper table lifting drive device 14 so that the support rod portion 3a rotates in the same direction and at approximately the same angle as the hopper table 1 as the hopper table 1 rises and falls. The means for connecting the hopper table lifting drive device 14 to the support rod portion 3a may be, for example, a link device, a cam device or the like.

Hereinafter, a more detailed explanation will be given based on the embodiment shown in FIGS. 4 to 6.

FIGS. 4 to 6 show an embodiment in which a link device is used as the linking means, and
Only the upper end portion of the support rod portion 3a of the separation claw 3 is loosely inserted into a through hole 5 provided in the immovable member 4 (medium guide plate 11), and is supported in this portion so as to be rotatable and movable up and down. A link 23 has two pins 21 and 22 planted laterally at its tip.
is provided with its base end being pivoted 24 to the drive pulley 17, and the tip of the link 23 is placed on the upper surface of the frame or other lower moving member 25 and is slidably supported, and the separation claw 3 The lower end of the support rod portion 3a is loosely inserted between the pins 21 and 22. Here, the hopper table elevating drive device 14, the link 23, and the immovable member 25 are provided on the side of the printing device so as not to interfere with the hopper table 1, the presser plate 12, or the support rod portion 3a of the separation claw. Of course, the pins 21 and 22 are planted inward on the link 23 provided on the side,
The lower end of the support rod 3a is loosely inserted between the pins 21 and 22. It should be noted that members other than the above shown in FIGS. 4 to 6 with the same reference numerals as in FIG. 1 are members having the same configuration and operation as explained in FIG. 1.

The operation of the separation pawl 3 supported by the structure described above is illustrated in FIGS. 5 and 6. In the state shown in FIG. 5, where the maximum amount of media sheets 7 are loaded on the hopper table 1, the hopper table 1 is at its lower end, and the hopper table 1 and the media sheets 7 are tilted unfavorably. The pivot point 24 between the drive pulley 17 and the link 23 is located at the farthest position from the holding plate 12, and the pins 21 and 22 installed in the link 23 touch the lower end of the support rod 3a of the separation claw on the holding plate 12. direction, the separation claw 3 faces upward, and the media paper 7
The angle between the upper surface of the separation claw 3 and the separation claw 3 is the same. As the media paper 7 is fed to the printer, the drive pulley 17 rotates clockwise in the figure, causing the hopper stand 1 to rise while rotating clockwise. Accordingly, the link 23 moves to the left in the figure, and the separation claw 3 rotates clockwise about the upper end of the support rod 3a. In the state shown in FIG. 6 in which the last sheet of the stacked media sheets 7 is fed, the driving pulley 17 rotates approximately half a turn from the state shown in FIG. As a result, the angle of the separation claw 3 rotated downward matches the angle of the medium paper 7, which is turned upward as the hopper table 1 rotates upward. The relationship between the angle of the upper surface of the hopper table 1, that is, the medium paper 7, and the angle of the separation claw 3 is shown in FIG. 7, where the horizontal axis in FIG. The state in FIG. 5 is shown with a rotation angle of 0 degrees, and the state in FIG. 6 is shown with a rotation angle of 180 degrees. The vertical axis is the angle of the separation claw 3 and the hopper stand 1, where the change in the angle of the separation claw 3 due to rotation of the drive pulley 17 is shown by a curve a, and the change in the angle of the hopper stand 1 is shown by a straight line b. . Since the amount of rotation of the hopper stand 1 is about 20 degrees at most,
The angle change of the hopper stand 1 with respect to the rotation angle of the drive pulley 17 may be approximated by a straight line b, and the angle change of the separation claw 3 will be a curve a approximated to a sine curve.
A straight line c parallel to the horizontal axis indicates the angle of the separation claw having the conventional support structure shown in FIG.

As is clear from FIG. 7, in the conventional support structure for the separation claw 3, an angular difference corresponding to e and f occurs between the separation claw 3 and the media sheet 7 at the ascending end and the descending end of the hopper table 1. However, according to the support structure of the present invention, it is possible to keep the angle difference between the separation claw 3 and the medium paper 7 small as the hopper table 1 moves up and down, and to minimize the occurrence of paper feeding mistakes and double-sheet feeding. can be reduced. Further, in the above embodiment, the drive pulley 1
The hopper stand 1 moves from its descending end to its ascending end while the drive pulley 1 rotates half a rotation.
For example, by increasing the diameter of the drive pulley 17,
If the hopper table 1 moves from the lower end to the upper end during 1/3 rotation, the separating claw 3 and the media paper 7
It is possible to keep the angular difference between the Furthermore, as shown in FIG. 8, if the cam 26 is used as a means for linking the support rod 3a and the hopper table lifting drive device 14, the angle of the separating claw 3 and the medium can be adjusted over the entire lifting stroke of the hopper table 1. It is also possible to match the angle of the paper 7. In FIG. 8, 27 is a camshaft that rotates in conjunction with the drive pulley 17, and the support rod 3a of the separation claw 3 is bent obliquely 28 so as to come into contact with the circumferential surface of the cam 26 due to its own weight. and extends downward.

As explained above, according to the supporting structure of the paper separation claw according to this invention, when the angle of the medium paper placed on the hopper table that rotates up and down changes as the hopper table moves up and down, the separation nail The angle of the separation claw also changes accordingly, so the change in the contact angle between the separation claw and the media sheet can be reduced, and if necessary, this change can be made zero, thereby preventing a decline in the function of the separation claw. This has the effect of preventing paper feeding errors and feeding two sheets of media.

[Brief explanation of the drawing]

Fig. 1 is a side view showing the main parts of a conventional printer device, Figs. 2 and 3 are partial side views showing the relationship between the media sheet and the separating claw in the conventional printer, and Fig. 4 is the separating claw of this invention. FIGS. 5 and 6 are side views showing essential parts of a printer device that employs the support structure shown in FIG. 4, and FIGS.
The figure is a graph showing how the angle between the hopper stand and the separating claw changes, where the horizontal axis is the rotation angle of the hopper stand lifting device, and the vertical axis is the angle of the hopper stand and the separating claw. FIG. 8 is a side view of main parts showing another embodiment. In the figure, 1 is a hopper stand, 2 is a pivot pin, 3 is a separating claw, 3a is a support rod, 4 is a stationary member, 5 is a through hole,
7 is a medium paper, 11 is a medium guide plate, 12 is a presser plate, 13 is a pick crawler, 14 is a hopper table lifting device, 17 is a drive pulley, 18 is a driven pulley, 19
is a belt, 20 is a locking pin, 21 and 22 are pins,
23 is a link, 24 is a pivot pin, 25 is a stationary member, and 26 is a cam.

Claims (1)

[Claims for Utility Model Registration] A paper separation claw that functions to separate the media sheets one by one by locking both corners of the leading edge of the supply media sheets 7 stacked on the hopper table 1 that rotates up and down. 3, the upper end of the support rod part of the separation claw having a support rod part 3a extending downward is rotatably and vertically supported by a frame or other immovable member 25, and the support rod part 3a is supported below the support rod part. The hopper table elevating drive device 14 is configured such that the rod portion rotates in the same direction as the hopper table as the hopper table moves up and down, and the angle of the paper separation claw with respect to the leading edge of the medium paper on the hopper table is maintained substantially constant. characterized by being linked,
A support structure for a paper separation claw in an automatic paper feeder.