JP3402119B2 - Paper feeder - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet feeding device.
For example, the present invention relates to a sheet feeding device that feeds a sheet to an image forming apparatus such as a printer, a facsimile, and a copying machine. 2. Related Art The present applicant has already proposed a paper feeder as shown in FIGS. 7 and 8 as Japanese Patent Application No. 8-298043. [0003] The sheet feeding device SF includes a frame 100,
Paper feed roller shaft 11 rotatably supported by this frame
0, a pair of feed roller units 120 and 120 ′ attached to the feed roller shaft 110, and a frame 10.
And a hopper 130 that is rotatably mounted with respect to zero. An edge guide 131 slidable in the sheet width direction is attached to the hopper 130. One of the pair of paper feed roller units 120 and 120 ′ is connected to the edge guide 131 and is slidable along the paper feed roller shaft 110 together with the edge guide 131. I have. [0005] Such a paper feeder SF is, for example, shown in FIG.
As shown in the figure below. In FIG.
Reference numerals 2 and 3 denote transport roller pairs for transporting paper, 4 denotes a print head for printing on paper, 5 and 6 denote paper discharge roller pairs for discharging printed paper, and 8a and 8b denote paper guides. The hopper 130 is inclined as shown, and a plurality of sheets P (FIG. 8) are set thereon in a stacked state. The edge guide 131 shown in FIG. 7 is slid in accordance with the width of the sheet set by the user, and guides one side edge of the fed sheet. The other side edge is
It is guided by the side wall 101 of the frame 100. Therefore, the other sheet feeding roller unit 120 is connected to the sheet feeding roller shaft 1.
Do not slide on 10. A pair of paper feed roller units 120 and 12
0 'is configured symmetrically and differs only in whether or not it slides. Therefore, only one sheet feed roller unit 120 will be described below. Reference numeral 121 denotes a paper feed roller, which is an arc portion 121.
a and a linear portion 121b, and has a substantially D shape in side view, and at least the surface of the arc portion 121a and the surface of the linear portion 121b are formed of a high friction material (for example, rubber). The paper feed roller shaft 110 is driven to rotate just one rotation during the paper feed operation by a driving means (not shown) of the printer via a gear 111 (see FIG. 7) fixed to the shaft end. ing. The hopper 130 is rotatably attached to the frame 100 by a shaft 132. Reference numeral 137 denotes a paper feed tray, which is attached to the printer. These hopper 130 and paper feed tray 137
On the top, a plurality of sheets P are set in a stacked state (FIG. 8).
reference). The set paper P is supported and aligned by the leading end Pa of the paper P contacting the back surface (support surface) 152 of the separation pad holder 151 described later. Reference numeral 140 denotes a frame (hereinafter, referred to as a sub-frame) of the sheet feeding roller unit 120, and a hopper spring (compression spring) 133 is provided between the sub-frame 140 and the tip of the hopper 130. Therefore, the hopper 130 is constantly urged by the hopper spring 133 in the clockwise direction in FIG. 8, that is, in the direction in which the sheet P is brought into contact with the paper feed roller 121, but as shown in FIG. Has a cam follower 134
The cam follower 134 is in contact with a hopper cam 135 fixed to the paper feed roller shaft 110, thereby restricting the rotation of the cam follower 134. Note that a pad 136 similar to a separation pad described later is provided on the top surface of the tip of the hopper 130. In FIG. 8, reference numeral 150 denotes a separation pad, which is fixed to a separation pad holder 151. The separation pad 150 is made of a material (for example, a material such as cork) whose friction coefficient with respect to the paper P is smaller than the friction coefficient of the paper feed roller 121. Each of the friction coefficients is made of a material having a friction coefficient larger than the friction coefficient between sheets. That is, if the friction coefficient between the paper feed roller 121 and the paper is μ1, the friction coefficient between the separation pad 150 and the paper is μ2, and the friction coefficient between the papers is μ3,
μ1>μ2> μ3. The separation pad holder 151 holds the separation pad 1
A pad support portion 153 to which the sheet 50 is fixed, a support surface (rear surface) 152 at the leading end of the sheet integrated with the pad support portion 153, and an arm portion 154 formed integrally therewith are provided. The shafts 155 provided on both sides of the rear end are rotatably attached to the sub-frame 140 by fitting into the holes of the sub-frame 140. A pad spring (compression spring) 156 is provided between the lower surface of the pad support 153 and the subframe 140 as pad urging means. Therefore, the separation pad holder 151 is constantly urged by the pad spring 156 in the clockwise direction in FIG. 8, that is, in the direction in which the separation pad 150 is brought into contact with the paper feed roller 121. Is formed with a projection (not shown).
The rotation is restricted by abutting on a pin (not shown) serving as a pad restricting means provided in the above. In a state where the protrusion is in contact with the pin, the separation pad 150 is
The paper feed roller 121 is located in the rotation orbit of the arc portion 121a. Reference numeral 160 denotes an idle roller, which is pressed against the separation pad 150 by a biasing means (not shown) with a biasing force smaller than that of the pad spring 156. The sheet feeding device SF as described above is built in the printer as described above, and is a driving means of the printer, and the sheet feeding roller shaft 110 is driven by a gear 111 (see FIG. 7).
Is driven as follows, so that it operates as follows. During standby, the hopper 130 is pushed down because the cam follower 134 of the hopper 130 is in contact with the hopper cam 135.
The paper feed roller 121 is in a state where the linear portion 121b faces the paper P, and the paper feed roller 121 is not in contact with the paper P. Accordingly, in this state, the sheet P can be easily set on the hopper 130, and the edge guide 131 is slid according to the width of the sheet P to guide the side edges of the sheet. can do. When the edge guide 131 is slid, the paper feed roller unit 120 'is also slid accordingly. In the paper feeding operation, the paper feeding roller shaft 110 rotates clockwise in FIG. 8, and the paper feeding roller 121 and the hopper cam 135 rotate together with the paper feeding roller shaft 110 to rotate the hopper cam 135 and the cam follower 134 of the hopper 130. When the contact with the sheet P is released, the hopper 130 is pushed up by the hopper spring 133, and the sheet P is also pushed up. P1 is sent toward the separation pad 150. At this time, the sheet P2 is fed together with the sheet P1 because the next sheet P2 is attracted to the sheet P1 by the action of static electricity or a frictional force acts between the sheet P1 and the sheet P2. However, the sheet P2 may be temporarily separated from the sheet P1 because the movement of the sheet P2 is hindered by the leading end P2a of the sheet P2 abutting against the separation pad 150. Similarly, even if a lower-order sheet P3 or the like is to be sent, it can be separated in the same manner. Further, as the paper feed roller shaft 110 continues to rotate, the arc portion 121a of the paper feed roller 121 presses the separation pad 150 via the uppermost sheet P1, whereby the separation pad 150 is moved by the pad spring 156. The pad spring 156 is simultaneously pressed down against the urging force.
, The uppermost sheet P1 is pressed between the sheet feeding roller 121 and the arc portion 121a. That is, the paper P
1 is fed in a state of being pinched between the paper feed roller 121 and the separation pad 150. At this time, as described above, the next paper P2 may be likely to be sent together with the paper P1, but as described above, the friction coefficient between the paper feed roller 121 and the paper is μ1, and the separation pad 150 is The coefficient of friction between paper and μ2, the coefficient of friction between paper μ3
Then, since μ1>μ2> μ3, when the paper P1 and the paper P2 are both pressed by the arc portion 121a of the paper feed roller and the separation pad 150 as the paper feed roller 121 rotates, The paper P2 is the separation pad 150
The movement is hindered by the frictional force between the sheet P1 and the sheet P1, and the sheet P2 is secondarily separated from the sheet P1, and only the sheet P1 is fed. The feed roller shaft 110 makes one full rotation, and the hopper 130 is pushed down by the hopper cam 135 to return to the standby state (the state shown in FIG. 8). At this point, the sheet P1 is not completely removed from the sheet feeding device, and the sheet P1 is not moved until its rear end passes the contact portion between the separation pad 150 and the idle roller 160. In a state where a load is applied to the contact portion (a state where the transfer roller is pulled backward),
Will be transported. In this case, since the idle roller 160 is urged by the roller spring 165 toward the separation pad 150 and presses the sheet P1 with the separation pad 150, the next roller already separated from the sheet P1 This prevents the sheet P2 from descending due to its own weight, or from being attracted to the sheet P1 by the action of static electricity or from being sent together with the sheet P1 by a frictional force with the sheet P1. In the paper feeder having the above-described configuration, when the edge guide 131 is slid, the paper feed roller unit 120 'is also slid. A space S (see FIG. 7) for allowing the paper feed roller unit 120 'to slide is required at the front. However, when there is such a space S, if the width of the sheet P (the length in the direction perpendicular to the sheet surface in FIG. 8) is large, the center of the sheet P is
Since the sheet is not supported by 0, the central portion is slackened downward, and when the sheet is fed in such a state, the sheet may be jammed or wrinkled. An object of the present invention is to solve the above-described problems and to provide a paper feeder capable of preventing paper jam and occurrence of wrinkles. According to a first aspect of the present invention, there is provided a paper feeder comprising: a pair of paper feed rollers for feeding paper in contact with both ends of the paper; A hopper for stacking a plurality of sheets to be fed in contact with a roller and pressing the sheet toward a sheet feeding roller, wherein the edge guides a side edge of the sheet and is slidable in a sheet width direction. A hopper having a guide, and a separation pad for separating the sheet to be fed by the sheet feeding roller from the next sheet by sandwiching the sheet between the sheet feeding roller and the sheet pressing roller. A sheet feeding device in which at least one of the pair of sheet feeding rollers and a separation pad slides in the sheet width direction together with the edge guide, and is provided so as to be able to protrude and retract in the sheet feeding direction with respect to the hopper. A supporting member for supporting the central portion of the sheet when the sheet is projected , and the supporting member is normally urged by an urging means.
The edge gear which is urged to the projecting side and slides
Slide with the edge guide or this edge guide
Characterized in that it is stored in the hopper side by being in contact with the guide member . According to the sheet feeding apparatus of the first aspect, a pair of sheet feeding rollers for feeding the sheet in contact with both ends of the sheet, and feeding in contact with the sheet feeding roller. A hopper for stacking a plurality of sheets to be formed and pressing the sheets toward a paper feed roller;
A separation pad that separates the paper to be fed by the paper feed roller from the next paper by pressing the paper against the paper feed roller and squeezing the paper between the paper feed roller. The uppermost sheet of the plurality of sheets is fed by the paper feed roller, and is separated by the separation pad, and only the highest sheet is fed. The hopper has a slidable edge guide, and at least one of the pair of paper feed rollers and the separation pad slide in the paper width direction together with the edge guide. Therefore, even paper having different widths can be fed by sliding the edge guide to guide the side edges. According to the paper feeder of the first aspect, the paper feeder is provided so as to be able to protrude and retract in the paper feed direction with respect to the hopper, and is provided with a support member for supporting the central portion of the paper when the paper is projected. Even if the width of the is large, since the central portion will be supported by the support member,
The downward slack of the central portion is prevented, and consequently, paper jam and wrinkles are prevented from occurring. That is, according to the sheet feeding apparatus of the first aspect, at least one of the pair of sheet feeding rollers and the separation pad slide in the sheet width direction together with the edge guide. In this case, it is possible to prevent paper jams and the occurrence of feed wrinkles. In addition, since the supporting member is provided so as to be able to protrude and retract in the sheet feeding direction with respect to the hopper, when the small width paper is set on the hopper, the supporting member is moved when the edge guide is slid. Side, so that the support member does not prevent the edge guide from sliding. Furthermore, prior Symbol support member is normally urged protruding side by the biasing means, is accommodated in the hopper side by contacting with the slide member which slides with the edge guide or the edge guide slides When the edge guide is slid to set narrow paper on the hopper, the support member is automatically stored in the hopper and the edge is set to set the wide paper on the hopper. When the guide is slid, the support member automatically projects from the hopper. That is, since the movement of the support member is automatically performed by the sliding operation of the edge guide,
The user's labor can be reduced. Embodiments of the present invention will be described below with reference to the drawings. This embodiment is similar to the above-mentioned Japanese Patent Application No. Hei.
This is an improvement of the paper feeding device of No. 98043, and the configuration other than the improved points is the same as that of the paper feeding device of No. 298043 of Japanese Patent Application No. Hei 8-No. FIGS. 1 and 2 are plan views each showing a hopper as a main part of this embodiment. In these figures, the same parts as those shown in FIGS. 7 and 8 are denoted by the same reference numerals. The feature of this embodiment is that, as shown in FIGS. 1 and 2, the hopper 130 is provided so as to be able to protrude and retract in the sheet feeding direction (the direction of arrow Y in FIG. 1), and as shown in FIG. The point is that a support member 138 for supporting the central portion of the sheet when projecting is provided. FIG. 3 is a view showing details of the support member 138.
(A) is a bottom view, (b) is a left side view when FIG. (A) is viewed from the front, (c) is a cross-sectional view taken along the line cc in FIG.
FIG. 3D is a sectional view taken along line dd in FIG. Also,
4 and 5 show the hopper body 130a.
(A) is a plan view, (b) is a front view, and (c) is a right side view when FIG. FIG. 5A is a bottom view, and FIG. 5B is a bottom view when FIG. FIG. 6 is a perspective view showing a state in which the support member 138 is assembled into the hopper main body 130a, and shows the hopper main body 130a upside down. As shown in FIG. 3, the support member 138 is integrally formed in a substantially plate shape as a whole, and has a substantially disk-shaped base portion 138a and a support portion 138b. Base 13
8, a hole 138c serving as a rotation center and a spring hook 138d described later are formed. On the other hand, as shown in FIGS. 4, 5 and 6, the hopper main body 130a has a support member 13 at its bottom.
A substantially circular recess 130c for receiving the base 138a
(See FIGS. 5A and 4B) and the support portion 138.
a rectangular recess 130b for receiving (storing) b
(See FIGS. 4A and 4B). In the center of the circular recess 130c, a shaft 130d that is rotatably fitted to the hole 138c of the support member is formed. In front of the circular recess 130c, a through hole 130e is formed as shown in FIG. 5A and FIG. Therefore, as shown in FIG. 6, the support member 138 is formed so that its disc-shaped base 138a is
e, into the recess 130c, and into the hole 138c
Is fitted to the shaft 130d to be rotatably attached to the hopper body 130a. The support member 138 attached in this manner can support the central portion of the sheet when protruded as shown in FIG.
By turning clockwise in the figure,
It can be stored in the recess 130b of the hopper body 130a. In this embodiment, the hopper body 130a
As shown in FIGS. 5A and 6, a spring hook 130 f is formed on the bottom surface of the spring.
As shown in FIGS. 1 and 6, a tension spring 139 as an urging means is attached between the support member 138 and the hook 138d of the support member 138. Therefore, the support member 138 is prevented from falling off the hopper main body 130a by the extension spring 139. The support member 138 is always urged to the protruding side by the tension spring 139 as shown in FIG. 1, but when the edge guide 131 is slid as shown in FIGS. By contacting, it rotates as shown in FIG.
Is stored in. The edge guide 131 is connected to one of the sheet feeding roller units 120 ′ at a connecting portion 131 a thereof.
0 ′, that is, a slide member that slides with the edge guide 131 (for example, the paper feed roller 12
1, the separation pad 150, the sub-frame 140, etc.) so that the support member 138 can be stored. According to the above-described paper feeder, the following operation and effect can be obtained. (A) A pair of paper feed rollers 121 and 121 for feeding paper in contact with both ends of the paper, and this paper feed roller 1
A plurality of sheets P to be fed in contact with the sheet 21 are stacked, and a hopper 130 that presses the sheet toward the sheet feeding roller 121, and a sheet feeding roller 12 that is pressed against the sheet feeding roller 121.
1 between the paper feed rollers 12
1 and the separation pad 150 for separating the sheet P1 to be fed from the next sheet P2 from the next sheet P2. Therefore, during the sheet feeding operation, the top sheet P1 of the plurality of sheets is fed by the sheet feeding roller. In addition, only the uppermost sheet P1 separated by the separation pad 150 is sent. The hopper 130 has a slidable edge guide 131 and a pair of paper feed rollers 121.
And at least one of the paper feed rollers 121 and the separation pad 150 are slid in the sheet width direction together with the edge guide 131. Therefore, even for sheets having different widths, the edge guide 131 is slid and the side edges thereof are moved. Can be sent as if guided. According to the paper feeder of this embodiment, the support member 138 is provided so as to be able to protrude and retract from the hopper 130 in the paper feed direction, and supports the central portion of the paper P when protruding as shown in FIG. Therefore, even when the width of the sheet P is large, the central portion thereof is supported by the support member 138, so that the central portion is prevented from slacking downward. Also, the occurrence of feed wrinkles is prevented. That is, according to the paper feeder of this embodiment, at least one of the pair of paper feed rollers 121, 121 and the separation pad 150 slide in the paper width direction together with the edge guide 131. In the configuration described above, it is possible to prevent paper jam and generation of feed wrinkles. Further, since the support member 138 is provided so as to be able to protrude and retract in the sheet feeding direction with respect to the hopper 130,
As shown in FIG. 2, when the edge guide 131 is slid to set a small width paper on the hopper, the support member 138 can be stored in the hopper 130 side. There is no hindrance to the 131 slide. (B) The supporting member 138 is provided with an urging means 139.
The hopper 130 is always urged to the projecting side by contact with the sliding edge guide 131.
When the edge guide 131 is slid as shown in FIG. 2 in order to set a small width paper on the hopper 130,
When the edge guide 38 is automatically stored in the hopper side and the edge guide is slid as shown in FIG.
30 will automatically protrude. That is, when the support member 138 moves in and out,
Since the operation is automatically performed by the slide operation of the edge guide 131, the user's labor can be reduced. As described above, one embodiment of the present invention has been described. However, the present invention is not limited to the above-described embodiment, and can be appropriately modified within the scope of the present invention. According to the paper feeder of the first aspect, at least one of the pair of paper feed rollers and the separation pad slide in the paper width direction together with the edge guide. In such a case, it is possible to prevent paper jams and wrinkles. [0057] In addition, it is possible to reduce the time and effort of Yu over The. [0058]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a plan view showing a hopper which is a main part of this embodiment. FIG. 2 is a plan view showing a hopper as a main part of the embodiment. 3A and 3B are diagrams showing details of a support member 138, where FIG. 3A is a bottom view, FIG. 3B is a left side view when FIG.
(C) is a cc cross-sectional view in FIG. (A), and (d) is a dd cross-sectional view in FIG. (A). 4A and 4B are diagrams showing a hopper main body 130a, where FIG. 4A is a plan view, FIG. 4B is a front view, and FIG. 4C is a right side view when FIG. 5A and 5B are views showing a hopper main body 130a, FIG. 5A is a bottom view, and FIG. 5B is a bottom view when FIG. FIG. 6 is a perspective view showing a state in which a support member 138 is incorporated into a hopper body 130a. FIG. 7 is an external perspective view of a sheet feeding device according to a related technique which is a premise of the embodiment of the present invention. FIG. 8 is a sectional view of the same. [Description of Signs] P paper 121 paper feed roller 130 hopper 131 edge guide 150 separation pad 138 support member 139 tension spring (biasing means)

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-8-244986 (JP, A) JP-A-6-234437 (JP, A) JP-A-5-97256 (JP, A) 25429 (JP, U) Shokai 63-172655 (JP, U) (58) Field surveyed (Int. Cl. ⁷ , DB name) B65H 1/04 310

Claims (1)

(57) Claims 1. A pair of paper feed rollers for feeding paper in contact with both ends of a paper, and a plurality of papers to be fed in contact with the paper feed roller are stacked. A hopper that presses the paper toward the paper feed roller, the hopper having an edge guide that guides a side edge of the paper and slides in the paper width direction; A separation pad that separates the paper to be fed by the paper feed roller from the next paper by nipping the paper between the rollers and at least one paper feed roller of the pair of paper feed rollers. A separation pad that slides in the sheet width direction together with the edge guide, and is provided so as to be able to protrude and retract in the sheet feeding direction with respect to the hopper, and includes a support member that supports a central portion of the sheet when the sheet protrudes. When Moni, the support member is always by a biasing means
The edge guide is urged to the projecting side and slides.
Or a slide that slides with this edge guide.
A sheet feeding device, which is stored in the hopper side by contacting the sheet member.