JP6218105B2 - Sheet material separating and feeding apparatus and image forming apparatus - Google Patents

Description

  The present invention relates to a sheet material separating and feeding apparatus and an image forming apparatus including the sheet material separating and feeding apparatus.

  Conventionally, an image forming apparatus mounted on a copying machine, a printer, a facsimile, an ink jet recording apparatus, etc., continuously feeds sheet materials from a sheet material stacking section capable of stacking sheet materials such as sheets as recording media. A feeding device is provided. In general, the feeding device includes a rotary conveying member that abuts on the uppermost sheet material stacked in a multi-layered manner, and a friction member that is disposed to face the rotary conveying member and separates the sheet material by a frictional force ( Friction pad).

  The sheet material fed out by one sheet or a plurality of sheets from the sheet material stacking portion is sandwiched between separation nip portions between the rotary conveyance member and the friction member. Then, due to the frictional force between the friction member and the sheet material, the sheets are separated one by one from the sheet material on the side in contact with the rotary conveying member and supplied to the printing unit of the image forming apparatus.

  FIG. 1 shows a laser printer 100 as an image forming apparatus according to an embodiment of the present invention. Here, the structure of a general image forming apparatus will be briefly described with reference to FIG. In FIG. 1, 1 is a photoconductor (image carrier), 2 is a charging device, 3 is a developing device, 4 is a developer cartridge, 5 is a fixing device, 6 is a paper discharge device, and 7 is a sheet material separating and feeding device. is there.

  The sheet material stacking unit 71 of the sheet material separating and feeding device 7 is urged to the rotary conveyance member 72 by an urging means (not shown). The sheet material P (hereinafter referred to as paper P) stacked on the sheet material stacking unit 71 first comes into contact with the rotary conveyance member 72. The paper P in contact with the rotary conveyance member 72 is sent to the timing roller 8 by the rotation of the rotary conveyance member 72. Thereafter, an image is transferred from the photosensitive member 1 to the paper P, and is discharged out of the apparatus through the fixing device 5 and the paper discharge device 6.

  As shown in FIG. 1, the sheet material stacking unit 71 is set at a predetermined angle from the horizontal plane with the leading end of the paper P in the feeding direction inclined downward. By setting the predetermined angle in this way, the installation area of the laser printer 100 can be reduced. Further, the weight of the paper P can be effectively used as the conveyance force. For this reason, the sheet material separating and feeding device 7 in which the feeding side of the sheet material stacking unit 71 is inclined downward as shown in FIG.

  In FIG. 2a, the force acting on the sheet P of the sheet material separating and feeding apparatus 7 is represented by arrows F1 and F2. As shown in FIG. 2a, the force F1 acts on the paper P by its own weight. For this reason, the force F1 caused by the weight of the paper P can be effectively used as the transport force. However, if the inclination angle θ of the sheet material stacking portion 71 is increased to a certain degree or more, double feeding is likely to occur. This is because when the force F1 due to the weight of the sheet P exceeds the frictional force F2 acting between the sheets, a plurality of sheets are bundled and enter the separation nip portion N.

  FIG. 2 b shows the relationship between the force with which the sheet moves toward the downstream in the feeding direction due to its own weight and the angle of the sheet material stacking unit 71. In the figure, F1 is the force that the paper tries to move downward. F21, F22, and F23 indicate frictional forces between the sheets. F21 is the frictional force when the friction coefficient μ = 0.8, F22 is μ = 0.6, and F23 is μ = 0.4.

  When the angle θ of the sheet material stacking portion is small as in the point A, the sheet does not slip downstream in the feeding direction. However, when the angle θ of the sheet material stacking portion is large as indicated by point B, the force with which the sheet tries to move exceeds its frictional force, and the sheet slides downstream in the feeding direction.

  Actually, the friction coefficient μ between papers varies depending on the type of paper and the environment such as temperature and humidity. In addition, a paper layer may be easily slipped by forming an air layer at a boundary portion due to the addition of the paper. For this reason, even if the angle θ is not increased too much, double feeding due to a bundle of sheets may occur.

  As described above, the sheet material separating and feeding apparatus having the sheet material stacking unit is effective because it can reduce the installation area of the printer. Non-feed due to increase is likely to occur. It is very difficult to reliably prevent double feeding of paper. Further, excessive friction between the paper and the friction member tends to promote wear of the friction member and damage the leading edge of the paper.

  In order to solve such a problem, it is conceivable to provide a guide portion 74a as shown in FIG. 3A upstream of the separation nip portion in the feeding direction and downstream of the front end of the stacked sheet material. The guide portions 74 a are integrally formed on the left and right ends of the holder 74 to which the friction member 75 is attached on both the left and right sides of the friction member 75. The guide portion 74 a has a top portion 74 b that protrudes from the surface of the friction member 75 toward the rotary conveyance member 72.

  Such a guide part 74a is specifically disclosed as “slip plate (50)” in Patent Document 1 (Japanese Utility Model Laid-Open No. 7-13852, FIG. 1), for example. The sliding plate (50) has moderate elasticity, is supported by the holder together with the friction member, and is urged toward the rotary conveying member by a separating pressure urging means such as a spring.

  However, in the separation and feeding apparatus of Patent Document 1, when a strong paper such as thick paper enters a bundle, the slip plate loses the strength of the paper and deforms toward the friction member. Therefore, the above-mentioned problem cannot be solved because the paper strongly hits the friction member.

  Further, if the sliding plate is hardened and fixed to the holder of the friction member, when a strong paper such as thick paper enters a bundle, the separation pressure by the spring is distributed to the paper P and the sliding plate. The arrow L in FIG. 3a indicates the force acting on the guide portion 74a from the paper P in such a case. For this reason, the separation pressure at the separation nip portion N is reduced and the pressure becomes insufficient. As a result, the overlapped sheets P cannot be separated and double feeding occurs.

  Patent Document 2 (Japanese Patent No. 4054459) discloses a sheet in which a portion lower than the friction member is formed on both left and right sides of the friction member, and a guide portion higher than the friction member is formed on the upstream side of the friction member. A material separating and feeding apparatus is disclosed. In the apparatus, the thin bundled sheet is rolled up when it passes over the guide part, and one or two sheets of the upper layer enter the separation nip part.

  Therefore, even when two sheets enter at the same time, the lower sheet is directly brought into contact with and separated from the friction member, thereby preventing the occurrence of double feeding. In addition, since the force of the biasing means is moderately distributed between the friction member and the guide portion in the thick bundled paper, the leading edge of the thick paper does not bite into the friction member or get caught.

  However, in the invention of Patent Document 2, the guide portion is formed wider than the friction member on the upstream side of the friction member. For this reason, the contact pressure between the paper and the friction member varies greatly depending on the combination of the height of the friction member and the strength of the paper. Therefore, when a stiff sheet such as a thick sheet enters in a bundle, it is difficult to reliably prevent the leading end of the sheet from strongly biting into or being caught by the friction member.

  Also, the separation pressure loss at the separation nip varies irregularly depending on the height of the friction member and the stiffness of the paper, so that the paper separation by the separation nip cannot be performed well, resulting in double feeding. There is a problem that occurs irregularly.

  In view of the above problems, the present invention is a sheet material separating and feeding apparatus in which the sheet material stacking portion is inclined downward from the upstream to the downstream in the feeding direction, thereby preventing the bundle of sheets from entering the separation nip portion. The purpose is to effectively prevent double feeding.

  In order to solve the above-described problems, the present invention provides a sheet material stacking unit capable of stacking the sheet material in a multi-layered manner with the sheet material feeding direction leading end inclined downward, and the sheet material stacking unit. A rotary conveying member that contacts the upper sheet material and conveys the sheet material downward, and a separation nip portion that is disposed below the rotary conveying member and through which the sheet material passes are formed. A friction member; first biasing means for biasing the friction member or the rotary conveying member toward the other side to apply a separation pressure to the sheet material sandwiched between the separation nip portions; and the separation nip portion and the sheet A guide portion that is fixedly disposed at a position that is between the material stacking portion and does not overlap with the upstream extension region of the separation nip portion, and a tip of the sheet material that enters the separation nip portion abuts on the guide portion. Sheet material characterized by having It is a Hanarekyu feeding apparatus.

  As described above, according to the present invention, the guide portion is provided between the separation nip portion and the sheet material stacking portion so as not to overlap the upstream extension region of the separation nip portion. Bundle entry can be prevented, and sheet material can be prevented from being double fed.

  Further, since the guide portion is fixedly arranged, even when a strong sheet material passes through the guide portion, the separation pressure of the separation nip is not affected by the force acting on the guide portion. Therefore, a stable separation action is always obtained with a stable separation pressure, and sheet material can be prevented from being double fed.

1 is a schematic view of a laser printer according to an embodiment of the present invention. It is a schematic sectional drawing of a sheet material separation feeding apparatus. FIG. 6 is a diagram illustrating a relationship between an inclination angle of a sheet material stacking unit and a force acting on a sheet. It is a fundamental sectional view showing a principal part of a separation part of a usual sheet material separation feeding device. It is a principal sectional view showing the important section of the separation part of the sheet material separation feeding device concerning an embodiment of the present invention. It is a perspective view of the sheet material separation feeding device concerning a 1st embodiment. It is sectional drawing of the sheet material separation feeding apparatus which concerns on 1st Embodiment. It is an expanded sectional view of the separation part of the sheet material separation feeding device concerning a 1st embodiment. It is a perspective view of the holder holding member of the sheet material separation feeding device concerning a 1st embodiment. It is a perspective view of the holder holding member of the sheet material separation feeding device concerning a 2nd embodiment. It is a front view of the holder holding member of the sheet material separation feeding device concerning a 2nd embodiment. It is a side view of the holder holding member of the sheet material separation feeding device concerning a 2nd embodiment. It is a perspective view of the holder holding member of the sheet material separation feeding device concerning a 3rd embodiment. It is a side view of the holder holding member of the sheet material separation feeding device concerning a 3rd embodiment. It is a perspective view of the holder holding member of the sheet material separation feeding device concerning a 4th embodiment. It is a side view of the holder holding member of the sheet material separation feeding device concerning a 4th embodiment. It is a perspective view of the holder holding member of the sheet material separation feeding device concerning a 5th embodiment. It is a top view of the holder holding member of the sheet material separation feeding apparatus concerning a 5th embodiment. It is a perspective view of the holder holding member of the sheet material separation feeding device concerning a 6th embodiment. It is a one end perspective view of the holder holding member of the sheet material separation feeding device concerning a 6th embodiment. It is a perspective view of the holder holding member of the sheet material separation feeding device concerning a 7th embodiment. It is a side view of the holder holding member of the sheet material separation feeding apparatus concerning a 7th embodiment. It is a perspective view of the holder holding member of the sheet material separation feeding device concerning an 8th embodiment. It is a one end part perspective view of the holder holding member of the sheet material separation feeding apparatus concerning an 8th embodiment. It is a perspective view of the holder holding member of the sheet material separation feeding device concerning a 9th embodiment. It is a one end part perspective view of the holder holding member of the sheet material separation feeding apparatus concerning a 9th embodiment. It is a perspective view of the holder holding member of the sheet material separation feeding device concerning a 10th embodiment. It is a perspective view of the holder holding member of the sheet material separation feeding device concerning an 11th embodiment. It is a side view of the holder holding member of the sheet material separation feeding apparatus concerning an 11th embodiment. It is a side view of the sheet material separation feeding device concerning a 12th embodiment. FIG. 6 is a side view of the vicinity of a guide portion of a sheet material separating and feeding device in which double feeding is likely to occur. FIG. 6 is a side view of the vicinity of a guide portion of a sheet material separating and feeding device in which double feeding is unlikely to occur. It is a side view of the sheet material separation feeding apparatus concerning a 13th embodiment. It is a side view of the guide part of the sheet material separation feeding apparatus concerning a 13th embodiment. It is a perspective view of the holder holding member of the sheet material separation feeding device concerning a 14th embodiment. It is a one end part perspective view of the holder holding member of the sheet material separation feeding apparatus concerning a 14th embodiment. It is a side view of the holder holding member at the time of the non-sheet feeding of the sheet material separation feeding apparatus concerning a 15th embodiment. It is a side view of the holder holding member at the time of paper feeding of the sheet material separation feeding device concerning a 15th embodiment.

  Hereinafter, a sheet material separating and feeding apparatus and an image forming apparatus according to an embodiment of the present invention will be described with reference to the drawings.

(Image forming device)
FIG. 1 shows an overall configuration of a laser printer 100 as an image forming apparatus. The laser printer 100 has a cylindrical photoreceptor 1 (image carrier). A charging device 2 that charges the surface of the photosensitive member 1 around the photosensitive member 1, and a developing device that develops an electrostatic latent image on the photosensitive member 1 with toner (developer) to form a toner image on the photosensitive member 1. 3 and a developer cartridge 4 containing a developer are disposed.

  The sheets P stacked on the sheet material stacking unit (paper tray) 71 of the sheet material separating and feeding device 7 are supplied to the timing roller 8 by the rotary conveying member 72, and the timing roller 8 synchronizes the sheet feeding timing to the photoreceptor 1. And supplied to the photoreceptor 1. When the toner image developed on the photoreceptor 1 by the developing device 3 is transferred to the paper P, the paper is then pressed and heated by the fixing device 5 to fix the toner image on the paper, and the paper discharge device 6 It is discharged outside the machine.

(Separation part of sheet material separation and feeding device)
FIG. 3B is a principle cross-sectional view showing the main part of the separation part of the sheet material separation and feeding apparatus 7 according to the embodiment of the present invention. A rectangular block-shaped holder holding member 73 is fixedly disposed on a machine frame or the like of the laser printer 100 at a position below the rotary conveyance member 72. In the center of the holder holding member 73, a vertical hole-shaped holder accommodating portion 73a is formed. A flat plate-like holder 74 is accommodated in the holder accommodating portion 73a so as to be movable up and down.

  A flat friction member 75 called a friction pad is fixed on the upper surface of the holder 74 with an adhesive or the like. A separation pressure spring 76 as a biasing means (first biasing means) is disposed between the bottom surface of the holder 74 and the bottom portion of the holder storage portion 73a, and the holder 74 is attached to the upper side by the separation pressure spring 76. It is energized. The friction member 75 on the holder 74 is in contact with the outer peripheral surface of the rotary conveyance member 72 by the separation pressure spring 76 when the sheet material P is not fed.

  A guide portion 77 is formed on the holder holding member 73 adjacent to the edge of the holder storage portion 73a. The guide portion 77 protrudes in the direction of the rotation conveyance member 72, and the top portion 78 protrudes higher than the upper surface of the friction member 75 toward the rotation conveyance member 72. In the illustrated example, the guide portion 77 is shown as a simple rectangular cross section, but the shape of the guide portion 77 can be various in order to enhance the effect of preventing double feeding, as shown in a plurality of embodiments described later. It can be shaped.

  In the present embodiment, the guide portion 77 is disposed not in the vertically movable holder 74 in FIG. As a result, even when a strong paper such as thick paper enters the separation nip portion N in a bundle shape, no pressure loss occurs in the separation nip portion N due to the separation pressure spring 76. For this reason, it is possible to prevent a decrease in the separation pressure due to the repulsive force of the sheet stiffness, thereby reducing the risk of double feeding.

Hereinafter, first to fifteenth embodiments of the sheet material separating and feeding apparatus will be described in order with reference to FIGS. 4A to 18B.
(First embodiment)
FIG. 4A is a perspective view of the sheet material separating and feeding apparatus according to the first embodiment. FIG. 4B is a cross-sectional view at the center in the rotational axis direction of the rotary conveying member 72 of the separation feeding device. FIG. 4c is an enlarged cross-sectional view of the guide part 77 which is a main part of the separation and feeding apparatus. FIG. 4 d is a perspective view of the holder holding member 73 having the guide portion 77.

  As shown in FIGS. 4a and 4b, the sheet material stacking unit 71 is set at a predetermined angle from the horizontal plane with the leading end of the sheet P in the feeding direction inclined downward, and the sheets P can be stacked in layers on the sheet P. It is said that. The sheet material stacking portion 71 is disposed so as to be swingable in the contact / separation direction with respect to the rotary conveyance member 72 around the support shaft 71a at the upper end thereof.

  The sheet material stacking unit 71 is constantly urged toward the rotary conveyance member 72 by a spring 71b as an urging unit (third urging unit) attached to the lower surface thereof. A holder holding member 73 is fixedly disposed below the rotary conveyance member 72. A plurality of mounting holes 84 for screwing and fixing to the machine frame or the like of the laser printer 100 are formed on the left and right sides of the holder holding member 73.

  As shown in principle in FIG. 3B, a holder 74 is attached to the holder holding member 73 so as to be movable up and down. In a shallow recess 74a on the upper surface of the holder 74, a rectangular flat plate-like friction member (friction pad) 75 is fixed with an adhesive or the like as shown in FIG. 4C. The friction member 75 is disposed on an extension of the center line that bisects the width direction of the sheet material stacking portion 71. Then, the uppermost sheet P of the sheet material stacking unit 71 is configured to be conveyed on the center reference by the rotation conveying member 72.

  The upstream end of the friction member 75 in the feeding direction is substantially the same height as the upper surface of the holder 74, but the upper surface of the holder 74 is formed slightly lower at the downstream end of the friction member 75 in the feeding direction. As a result, the paper P that has passed through the separation nip N is smoothly conveyed downstream.

  A separation pressure spring 76 is disposed between the holder 74 and the holder holding member 73. The holder 74 is held by the holder holding member 73 through the separation pressure spring 76 so as to be movable up and down. In addition, a holder restricting portion 94 is provided below the downstream rear end of the holder 74 in order to restrict the maximum pressing amount of the holder 74. The holder restricting portion 94 is formed integrally with the holder holding member 73.

  At a position that does not overlap with the upstream extension region of the separation nip portion N, a guide portion 77 is provided on which the leading edge of the paper P entering the separation nip portion N abuts. A pair of guide portions 77 are disposed on the left and right sides of the holder 74 between the separation nip portion N and the sheet material stacking portion 71, and are integrally formed with the holder holding member 73. By this integral formation, the accuracy of the guide portion 77 can be improved, and the cost can be reduced by reducing the material used and the number of parts.

  As shown in FIG. 4C, the guide portion 77 has a mountain shape that protrudes toward the rotary conveyance member 72 in an inverted V shape on the upstream side of the friction member 75 in a side view. The top portion 78 of the guide portion 77 protrudes higher than the friction member 75 toward the rotary conveyance member 72. In addition, for the stable conveyance of the paper P, a conveyance guide surface 83 that is bent upward after a short linear downward inclination and has a long linear upward inclination is formed continuously downstream of the guide portion 77.

  When the number of the friction members 75 is one, the guide portions 77 can be disposed in a pair of symmetrical shapes on the left and right sides of the friction member 75 or the rotary conveyance member 72 as shown in FIG. The guide portion 77 may be disposed only at one position on one side of the friction member 75, or may be disposed at one position in the middle of the friction member 75 when the friction member 75 is disposed in a pair of left and right. .

  In this embodiment, basically, a pair of guide portions 77 are disposed on both sides of the friction member 75. And the center of a pair of guide part 77 is match | combined with the extended line of the centerline which bisects the width direction of the sheet | seat material stacking part 71. FIG. That is, the pair of guide portions 77 are arranged at symmetrical positions with respect to the extension line, the friction member 75, and the rotary conveyance member 72. As a result, the paper P can be introduced into the separation nip N equally left and right by the two-point support by the pair of guide parts 77, and the diagonal feeding (skew) of the paper P can be prevented.

  The distance between the pair of guide portions 77 is desirably smaller than the minimum sheet width (width dimension) that can be attached to the laser printer 100 and fed. As a result, the paper P of all sizes that can be handled by the laser printer 100 can be aligned by regulating the leading edge of the paper P, and double feeding and oblique feeding can be prevented.

  The top portion 78 of the guide portion 77 is desirably disposed so as to be in contact with the outer peripheral surface of the rotary conveying member 72 in a side view of FIG. Thereby, the gap between the outer peripheral surface of the rotary conveyance member 72 and the guide portion 77 can be made zero, and the leading end portion of the bundle of sheets P can be reliably brought into contact with the guide portion 77. Therefore, it is possible to reliably prevent the bundle of sheets P and the double feed due to the bundle. In addition, it is also possible to arrange | position the guide part 77 so that it may bite into the outer peripheral surface of the rotation conveyance member 72 in the side view of FIG.

  An inclined upstream guide surface 79 is desirably formed on the upstream side of the guide portion 77 in the feeding direction. Further, the entry angle of the sheet P with respect to the upstream guide surface 79 is an angle range in which the bundle of sheets P can be prevented from entering, and the angle is set as small as possible in order to suppress an increase in the conveyance load of the sheet P. Is desirable.

  Assuming that the angle formed by the upstream guide surface 79 and the uppermost surface of the loaded paper P is θ1, a range of 90 ° ≦ θ1 ≦ 180 ° is effective for preventing non-feeding. By setting in the range of 90 ° ≦ θ1 ≦ 180 °, the entry angle of the paper P with respect to the guide portion 77 becomes small, and non-feed due to an increase in the conveyance load can be prevented.

  The lower limit of θ1 is not limited to 90 °, and can be any of 100 °, 110 °, 120 °, 130 °, and 140 °, for example. The upper limit of θ1 is not limited to 180 °, and can be any one of 170 °, 160 °, and 150 °, for example.

  Further, an inclined downstream guide surface 80 is desirably formed on the downstream side of the guide portion 77 in the feeding direction. Assuming that the angle formed by the downstream guide surface 80 and the surface of the friction member 75 downstream from the separation nip portion N in the feeding direction is θ2, the angle θ2 is desirably set in a range of 0 ° ≦ θ2 ≦ 90 °. More preferably, the angle θ2 is set to 35 ° or less.

  Thereby, the entry angle of the paper P with respect to the friction member 75 becomes small, and non-feeding due to an increase in the conveyance load can be prevented. Further, it is possible to prevent catching due to burrs at the front end of the paper, and it is possible to prevent damage to the front end of the paper.

(Second Embodiment)
FIG. 5A is a perspective view of a holder holding member 73B of the sheet material separating and feeding device according to the second embodiment. FIG. 5B is a projection view of the holder holding member 73B as viewed from the upstream side in the feeding direction. FIG. 5 c is a projection view of the holder holding member 73 </ b> B viewed from a direction orthogonal to the feeding direction. In the subsequent drawings including FIG. 5a to FIG. 5c, the holder and the friction member are omitted as appropriate.

  The feature of the holder holding member 73B is that, as shown in FIG. 5B, the shape of the top portion 78B of the guide portion 77B is a curved surface (R surface) that is upwardly convex when viewed from the feeding direction. Thereby, the conveyance resistance of the paper P can be reduced, the damage of the paper P can be suppressed, and the wear of the guide portion 77B can be reduced.

  Further, as shown in FIG. 5c, the shape of the top portion 78B of the guide portion 77B can be formed as a curved surface (R surface) that is upwardly convex when viewed from the direction orthogonal to the feeding direction. Thereby, the conveyance resistance of the paper P can be reduced, the damage of the paper P can be suppressed, and the wear on the top of the guide portion 77B can be reduced.

  Moreover, you may make it the curved surface (a part of spherical surface) which combined FIG. 5b and FIG. 5c. Similarly to the first embodiment, a conveyance guide surface 83B is formed continuously on the downstream side of the guide portion 77B. The conveyance guide surface 83B is bent upward after a short straight downward slope and becomes a long straight upward slope.

(Third embodiment)
FIG. 6A is a perspective view of a holder holding member 73C of the sheet material separating and feeding device according to the third embodiment. FIG. 6B is a projection view of the holder holding member 73C as viewed from a direction orthogonal to the feeding direction. The feature of this third embodiment is that the upstream guide surface 79C, which is upstream in the feeding direction from the top portion 78C of the guide portion 77C, has an arc shape that is convex upward. Further, the downstream guide surface 80C, which is downstream in the feeding direction from the top portion 78C of the guide portion 77C, is formed in an arc shape that protrudes upward.

  By making the upstream guide surface 79C into an arc shape that protrudes upward, the entry angle when the leading edge of the sheet rides on the upper surface of the guide portion 77C becomes gentle, and it is possible to prevent non-feed due to an increase in the conveyance load. Become. In addition, by forming the downstream guide surface 80 </ b> C into an arc shape that protrudes upward, the angle at which the front end of the paper enters the surface of the friction member 75 is reduced. Therefore, the leading edge of the paper can be prevented from being caught, and the leading edge of the paper can be prevented from being damaged.

  Further, by forming the upstream guide surface 79C and the downstream guide surface 80C in a concentric arc shape (curvature radius R), the holder holding member 73C having the guide portion 77C can be easily manufactured while satisfying the above-described effects. Therefore, a highly accurate sheet material separating and feeding apparatus can be provided at low cost. As in the first embodiment, for a stable conveyance of the paper P continuously on the downstream side of the guide portion 77C, a conveyance guide that is bent upward after a short linear downward inclination and becomes a long linear upward inclination. A surface 83C is formed.

(Fourth embodiment)
FIG. 7A is a perspective view of a holder holding member 73D of the sheet material separating and feeding device according to the fourth embodiment. FIG. 7B is a projection view of the holder holding member 73D as viewed from a direction orthogonal to the feeding direction. The holder holding member 73D is characterized in that the upstream guide surface 79D upstream of the top portion 78D of the guide portion 77D in the feeding direction is formed in a continuous uneven shape (or continuous staircase shape) with a height difference of 1 mm or less.

  With this continuous uneven shape (or continuous staircase shape), when the paper P rushes in a bundle, the leading edge of each paper P collides with the continuous uneven shape (or continuous staircase shape) and is moved while being shifted in a staircase shape. Double feeding can be prevented. As in the first embodiment, for the stable conveyance of the paper P continuously on the downstream side of the guide portion 77D, a conveyance guide that is bent upward after a short linear downward inclination and has a long linear upward inclination. A surface 83D is formed.

  The height difference of the continuous uneven shape (or continuous staircase shape) is preferably 1 mm or less. If the height difference is more than 1 mm, a plurality of papers P enter a concavo-convex shape, and the action of shifting in a staircase shape is greatly reduced. Further, if the height difference of the continuous uneven shape (or continuous staircase shape) is extremely reduced, the action of restraining the leading edge of the paper is greatly reduced, and the bundle of paper P cannot be spread.

(Fifth embodiment)
FIG. 8A is a perspective view of a holder holding member 73E of the sheet material separating and feeding device according to the fifth embodiment. FIG. 8B is a plan view of the holder holding member 73E. This holder holding member 73E is characterized in that the upstream guide surface 79E of the guide portion 77E is gradually narrowed toward the top portion 78E. Further, the downstream guide surface 80E of the guide portion 77E is gradually narrowed toward the top portion 78E.

  By forming the upstream guide surface 79E as described above, the leading edge of the sheet first hits the wide portion of the upstream guide surface 79E, and the conveyance load is distributed. Thereafter, as the leading edge of the sheet approaches the top portion 78E along the upstream guide surface 79E, it comes into sliding contact with the narrow portion of the upstream guide surface 79E. Thereby, the conveyance resistance of the paper P can be reduced, and paper damage can be prevented. The upstream guide surface 79E may be provided with a continuous uneven shape (or continuous staircase shape) as in the above-described fourth embodiment in order to improve the double feed prevention function.

  Further, by forming the downstream guide surface 80E as described above, the conveyance resistance when the paper P is brought into sliding contact with the top portion 78E of the guide portion 77E is reduced. Thereafter, as the paper P is transported, the rear end thereof is in sliding contact with the wide portion along the downstream guide surface 80E, so that the transport load due to the variation of the rear end of the paper is dispersed in the width direction.

  For this reason, damage to the paper P can be prevented. In order to improve the double feed prevention function, a plurality of guide portions may be formed on the downstream guide surface 80E as shown in FIGS. 14a and 14b of an eleventh embodiment to be described later. As in the first embodiment, for the stable conveyance of the paper P continuously on the downstream side of the guide portion 77E, a conveyance guide that is bent upward after a short linear downward inclination and has a long linear upward inclination. A surface 83E is formed.

(Sixth embodiment)
FIG. 9A is a perspective view of a holder holding member 73F of the sheet material separating and feeding device according to the sixth embodiment. The feature of the holder holding member 73F is that the guide portion 77F is configured separately from the holder holding member 73F and is detachable from the holder holding member 73F.

  The upper portion of the guide portion 77F is formed in a plate-shaped pentagon having an inverted V shape. That is, as in FIG. 4d, the guide portion 77F has an upstream guide surface and a downstream guide surface at the top. As in the first embodiment, for the stable conveyance of the paper P continuously on the downstream side of the guide portion 77F, a conveyance guide that is bent upward after a short linear downward inclination and has a long linear upward inclination. A surface 83F is formed.

  By configuring the guide portion 77F separately from the holder holding member 73F, the guide portion 77F as a part can be easily replaced and maintained, and the friction coefficient of the guide portion 77F due to the material of the holder holding member 73F is not restricted. That's it. Therefore, regardless of the material of the holder holding member 73F, the optimum material for the guide portion 77F can be selected, and the optimum friction coefficient for the upper surface of the guide portion 77F can be selected.

  Specifically, by making the friction coefficient of the guide part 77F smaller than the friction coefficient of the friction member 75, it is possible to suppress wear of the guide part 77F due to friction with the paper P and to reduce the conveyance load of the paper P. . Further, non-feeding due to excessive conveyance load can be prevented. On the contrary, by making the friction coefficient of the guide portion 77F larger than the friction coefficient of the friction member 75, it is possible to enhance the double feed prevention effect.

  In order to make the guide portion 77F detachable from the holder holding member 73F, a pair of short engagement shafts 83F and 84F are integrally formed on the inner surface of the lower portion of the guide portion 77F. Corresponding to the engaging shafts 83F and 84F, the holder holding member 73F is formed with two sets of horizontally-arranged round holes 81F and horizontally long holes 82F as attachment portions.

  By fitting the engagement shafts 83F and 84F into the round hole 81F and the horizontally long hole 82F, the guide portion 77F can be detachably attached to the holder holding member 73F. By making one of the holes in one set as the horizontally long hole 82F, the engagement shafts 83F and 84F of the guide portion 77F can be easily fitted. Further, the positioning accuracy with respect to the other round hole 81F improves the mounting accuracy of the guide portion 77F.

  The engagement shafts 83F and 84F of the guide portion 77F, and the round holes 81F and the horizontally long holes 82F of the holder holding member 73F may be arranged in reverse. That is, the round hole 81F and the horizontally long hole 82F may be formed in the guide portion 77F, and the engagement shafts 83F and 84F may be formed in the holder holding member 73F.

  The number of pairs of round holes 81F and horizontally long holes 81F is arbitrary. Further, the intervals in the vertical direction of each set are not necessarily equal. By providing the holder holding member 73F with a plurality of engaging portions, the position of the guide portion 77F can be adjusted.

  Therefore, for example, when the upper surface of the guide portion 77F is worn to some extent, the amount of protrusion of the upper surface from the surface of the friction member 75 is restored as in the initial state, so that the guide portion 77F is shifted upward and reattached. Can be implemented. As a result, the same effect as that of the new guide part 77F can be exhibited again, and the durability can be improved.

  Further, by configuring the guide portion 77F separately from the holder holding member 73F, it is possible to configure the guide portion 77F with a conductive material. Thus, frictional charging when the guide portion 77F and the paper P are in sliding contact can be prevented, and image loss when the image is transferred from the photoreceptor 1 to the paper P can be prevented. In addition, the attachment structure in which the guide portion 77F can be attached and detached is not limited to the above-described shaft-hole fitting structure. For example, the guide portion 77F may be vertically fitted in a vertical hole formed in the holder holding member 73F.

(Seventh embodiment)
FIG. 10A is a perspective view of a holder holding member 73G of the sheet material separating and feeding device according to the seventh embodiment. FIG. 10B is a projection view of the holder holding member 73G as seen from a direction orthogonal to the feeding direction. The holder holding member 73G is characterized in that the guide portion 77G is configured separately from the holder holding member 73G and in a rotatable cylindrical or disc shape. As in the first embodiment, for the stable conveyance of the paper P continuously on the downstream side of the guide portion 77G, a conveyance guide that is bent upward after a short linear downward inclination and has a long linear upward inclination. A surface 83G is formed.

  In order to rotatably support the guide portion 77G, a support shaft 77G1 is formed at the center of both left and right sides. The support shaft 77G1 is rotatably fitted in a groove 85G serving as a receiving portion on the rectangular frame 87G of the holder holding member 73G. As a result, the upper half of the guide portion 77G protrudes from the holder holding member 73G as shown in FIG. 10a. Note that the groove 85G has an inlet portion that is narrowly narrowed and cannot easily come off when the support shaft 77G1 is press-fitted into the groove 85G at the inlet portion.

  Since the guide portion 77G is rotatable, when the paper P slides on the top portion 78G of the guide portion 77G, the guide portion 77G rotates around the support shaft 77G1, thereby reducing the conveyance resistance of the paper P. Further, the wear of the guide portion 77G due to friction with the paper P can be prevented, and the durability thereof can be enhanced. Note that the support shaft 77G1 of the guide portion 77G may be urged toward the rotary conveyance member 72 by urging means (second urging means) as in an eighth embodiment described below. This makes it possible to transport the paper P more stably, and more effectively prevent double feeding and oblique feeding.

(Eighth embodiment)
FIG. 11 a is a perspective view of the holder holding member 73 </ b> H of the sheet material separating and feeding device according to the eighth embodiment. FIG. 11b is a perspective view of one end portion of the holder holding member 73H. The feature of the holder holding member 73H is that a separate guide portion 77H is supported by a spring 86H so as to be movable up and down. As in the first embodiment, for the stable conveyance of the paper P continuously on the downstream side of the guide portion 77H, a conveyance guide that is bent upward after a short linear downward inclination and has a long linear upward inclination. A surface 83H is formed.

  The upper portion of the guide portion 77H is formed in a plate-shaped pentagon having an inverted V shape. That is, as in FIG. 4d, the guide portion 77H has an upstream guide surface and a downstream guide surface at the top. A vertical groove 87H is formed in the holder holding member 73H to support the guide portion 77H so as to be movable up and down. The guide portion 77H is inserted into the vertical groove 87H. A restricting portion (not shown) is formed in the vicinity of the upper end portion of the vertical groove 87H to prevent the guide portion 77H from popping out. The guide portion 77H is urged upward by a spring 86H as urging means (second urging means), and its maximum height is restricted by the restricting portion.

  The spring constant of the spring 86H that supports the guide portion 77H so as to be movable up and down can be freely set to a required size. For this reason, the contact pressure between the guide portion 77F and the paper P can be arbitrarily controlled. That is, in addition to the separation nip portion N between the rotary conveyance member 72 and the friction member 75, it is possible to control the force for supporting the paper P. This makes it possible to transport the paper P more stably, and more effectively prevent double feeding and oblique feeding.

(Ninth embodiment)
FIG. 12A is a perspective view of a holder holding member 73I of the sheet material separating and feeding device according to the ninth embodiment. FIG. 12B is a perspective view of one end of the holder holding member 73I. The feature of the holder holding member 73I is that the guide portion 77I is configured separately from the holder holding member 73I and is movable in the width direction of the holder holding member 73I. As in the first embodiment, for the stable conveyance of the paper P continuously on the downstream side of the guide portion 77I, a conveyance guide that is bent upward after a short linear downward inclination and has a long linear upward inclination. A surface 83I is formed.

  In order to attach the guide portion 77I to the holder holding member 73I so as to be movable in the width direction, a guide groove 87I is formed in the holder holding member 73I. The guide portion 77I can be positioned by being moved to an arbitrary position in the width direction of the holder holding member 73I by a restriction portion (not shown). The position adjustment of the guide portion 77I may be performed by manual adjustment by the user, or may be performed by an automatic position adjustment mechanism using a solenoid or the like corresponding to the print instruction information.

  When the paper P is a strong paper P such as thick paper, if the guide portion 77I and the separation nip portion N are close to each other in the width direction, the paper P is hardly bent and deformed as shown in FIG. For this reason, the contact pressure between the guide portion 77I and the paper P becomes high, and the paper damage and the wear of the guide portion 77I are liable to occur due to excessive conveyance load at the guide portion 77I.

  Therefore, when the paper P is a firm paper P such as a thick paper, the position of the guide portion 77I is adjusted in a direction away from the separation nip portion N in the width direction. By doing so, the distance between the pair of left and right guide portions 77I is increased, and even in the strong paper P, the portion between the pair of guide portions 77I is pushed by the rotary conveying member 72 and bent toward the friction member 75 side. . Due to this bending, the contact pressure between the guide portion 77I and the paper P is relaxed. Therefore, paper damage and wear of the guide portion 77I due to excessive conveyance load at the guide portion 77I are suppressed.

  That is, by adjusting the position of the guide portion 77I according to the type of the paper P, a paper support point by the guide portion 77I corresponding to the paper P can be selected, and paper damage and wear of the guide portion 77I can be suppressed. . Of course, even if the width of the guide portion 77I is increased or decreased in this way, no pressure loss occurs in the separation nip portion N at all. Therefore, the frictional separation action of the separation nip portion N always functions normally regardless of the change in the width of the guide portion 77I.

(10th Embodiment)
FIG. 13 is a perspective view of a holder holding member 73J of the sheet material separating and feeding device according to the tenth embodiment. The holder holding member 73J is characterized in that a plurality of guide portions 77J (four left and right in the illustrated example) are arranged in the width direction. The number of guide portions 77J may be 2, 3 or 5 or more. By doing so, the contact point between the paper P and the guide portion 77J is increased, the leading edge alignment state of the paper P is stabilized, and the oblique feeding of the paper P can be prevented. As in the first embodiment, for the stable conveyance of the paper P continuously on the downstream side of the guide portion 77J, a conveyance guide that is bent upward after a short linear downward inclination and has a long linear upward inclination. A surface 83J is formed.

(Eleventh embodiment)
FIG. 14A is a perspective view of a holder holding member 73K of the sheet material separating and feeding device according to the eleventh embodiment. FIG. 14B is a projection view of the holder holding member 73K viewed from a direction orthogonal to the feeding direction. The feature of the holder holding member 73K is that an additional guide portion is formed adjacent to the downstream side of the guide portion 77K.

  That is, in this embodiment, two further guide portions 88K and 89K are formed downstream from the highest guide portion 77K. That is, a plurality of guide parts are formed in a step shape from the highest guide part 77K to the downstream side. As a result, even when the bundle of sheets P cannot be rolled by the first guide section 77K, the sheets P can be reliably rolled by the second guide section 88K and the third guide section 89K, thereby preventing double feeding. The effect can be enhanced. As in the first embodiment, for the stable conveyance of the paper P continuously on the downstream side of the guide portion 77K, a conveyance guide that is bent upward after a short linear downward inclination and becomes a long linear upward inclination. A surface 83K is formed.

(Twelfth embodiment)
FIG. 15 a shows a sheet material separating and feeding apparatus according to the twelfth embodiment. The sheet material separating and feeding device is characterized in that a paper leading edge receiving surface 90c formed on the upstream side of the holder holding member 73 is formed to be continuous with the upstream guide surface 79c of the guide portion 77 in a straight shape.

  In this way, when the sheet material stacking unit 71 swings around the support shaft 71a toward the rotary conveyance member 72 by the force of the spring 71b, the leading edge of the sheet smoothly moves from the leading edge receiving surface 90c to the upstream guide surface 79c. Can be introduced. Thereby, it is possible to prevent the boundary (air layer) from being generated on the paper P, and to prevent double feeding due to the bundle of paper P entering from above the boundary.

  On the other hand, as shown in FIG. 15 b, when the paper leading edge receiving surface 90 b that receives the leading edge of the paper P stacked on the sheet material stacking portion 71 is not on the extension line or the substantially extension line of the upstream guide surface 79 b of the guide portion 77. , Double feed is likely to occur. That is, as the sheet material stacking unit 71 swings, the leading end of the paper P stacked on the sheet material stacking unit 71 passes through the step (or steeply inclined portion) 95 from the paper front end receiving surface 90b and the guide unit 77. Is introduced into the upstream guide surface 79b.

  At this time, since the sheet material stacking portion 71 is inclined with respect to the horizontal plane, the leading end position of the paper P is shifted by the swinging about the support shaft 71a of the sheet material stacking portion 71. For this reason, an air boundary layer is formed between the sheets due to the shift, and the frictional force between the sheets is reduced. As a result, a bundle-like rush of sheets P above the air boundary layer is likely to occur, and the possibility of double feeding is increased.

  Therefore, in the present embodiment, as shown in FIG. 15 c, a paper leading edge receiving surface 90 c that receives the leading edge of the paper P is formed on an extension line of the upstream guide surface 79 c of the guide portion 77. In this way, even if the sheet material stacking portion 71 swings around the support shaft 71a, the leading edge of the sheet does not shift. Therefore, it is possible to avoid the formation of an air boundary layer between the sheets due to the deviation of the sheet leading end, and the sheet leading end can be smoothly introduced from the sheet leading end receiving surface 90c to the upstream guide surface 79c. Thereby, double feeding can be prevented.

(13th Embodiment)
16a and 16b show a thirteenth embodiment. In this embodiment, the swing locus of the lower end portion of the sheet material stacking portion 71 does not interfere with the upstream guide surface 79d of the guide portion 77 and the sheet leading edge receiving surface 90d provided on the extension line of the upstream guide surface 79d. It is a thing.

  That is, the sheet leading edge receiving surface 90d provided on the extended line of the upstream guide surface 79d is a straight line connecting the support shaft 71a of the sheet material stacking portion 71 and the leading edge of the sheet P when one sheet P is stacked. 91 is assumed. An upstream guide surface 79d and a paper front end receiving surface 90d are formed so as to be separated downstream in the feeding direction from a paper front end locus 92 represented by an arc locus drawn by the straight line 91 about the support shaft 71a.

  For example, the angle θ3 formed by the surface from the lower side to the upper side of the sheet leading edge receiving surface 90d and the straight line 91 connecting the support shaft 71a of the sheet material stacking unit 71 and the leading edge of the sheet when one sheet is stacked is Consider a case where the angle is greater than 90 °. In this case, because the sheet P is inclined from the horizontal plane, the leading edge of the sheet bites into the leading edge receiving surface 90d when the sheet material stacking portion 71 swings toward the rotation conveyance member 72 around the support shaft 71a. There is nothing.

  Therefore, it is possible to prevent the leading edge of the paper from being damaged. Further, there is no possibility that the sheet material stacking unit 71 cannot swing due to interference with the upstream guide surface 79d and the sheet leading edge receiving surface 90d. Accordingly, it is possible to prevent the occurrence of non-feed due to the fact that the paper P cannot be effectively urged toward the rotary conveyance member 72.

  FIG. 16B is an example in which the upstream guide surface 79e and the paper leading edge receiving surface 90e are not a straight line (plane) but a concave curve (concave surface). In other words, the upstream guide surface 79e and the paper leading edge receiving surface 90e are formed so as to be recessed in the feeding direction downstream side of the paper leading edge locus 92e. In this case, the same effect as that of FIG. 16a can be obtained.

(14th Embodiment)
FIG. 17A is a perspective view of a holder holding member 73L of the sheet material separating and feeding apparatus according to the fourteenth embodiment. The feature of the holder holding member 73L is that a thin plate-like slip plate 93L made of a member different from the holder holding member 73L is attached to the paper leading edge receiving surface 90L.

  This facilitates replacement and maintenance of the sliding plate 93L as a component, and does not require the restriction of the friction coefficient of the sliding plate 93L due to the material of the holder holding member 73L. Therefore, regardless of the material of the holder holding member 73L, it is possible to select the optimum material for the sliding plate 93L, and it is possible to select the optimum friction coefficient for the sliding plate 93L.

  Specifically, by making the friction coefficient of the sliding plate 93L smaller than the friction coefficient of the friction member 75, it is possible to prevent the sheet material stacking portion 71 from being caught on the sliding plate 93L when the sheet material stacking portion 71 swings (lifts and lowers). . In the absence of the low friction sliding plate 93L, the sheet leading edge receiving surface 90L is made of the same material as the holder holding member 73L, and the leading edge of the sheet is easily caught by the material.

  If the leading edge of the sheet is caught, the sheet material stacking unit 71 cannot swing (elevate) smoothly, and the sheet P cannot be biased toward the rotary conveying member 72. By using the slip plate having the optimum friction coefficient of another member as in the present embodiment, the paper P can be reliably urged toward the rotary conveying member 72 and non-feeding of the paper P can be prevented.

(Fifteenth embodiment)
18a and 18b are side views of a sheet material separating and feeding apparatus according to the fifteenth embodiment. 18A shows a state where the paper P is not being fed, and FIG. 18B shows a state where the paper P is being fed.

  Since the holder 74 is pushed down by the entry of the paper P, a holder regulating portion 94 is provided below the holder 74 in order to regulate the maximum amount of movement in the direction in which the holder 74 is pushed down. The holder restricting portion 94 is desirably formed integrally with the holder holding member 73 together with the guide portion 77 described above.

  As can be seen from FIG. 18 b, when the holder 74 is pushed down to the maximum and abuts against the holder restricting portion 94, the leading edge of the sheet and the friction member 75 depend on the height of the top 78 of the guide portion 77 and the height of the holder restricting portion 94. Is determined. If this positional relationship varies, the maximum gap between the upper surface of the holder 74 and the rotary conveying member 72 when the maximum depression is performed may vary, and a gap that allows the sheet P to enter the bundle shape may be formed.

  By forming the holder restricting portion 94 integrally with the holder holding member 73 together with the guide portion 77, it becomes easy to accurately determine the positional relationship between the front end of the sheet and the upper surface of the friction member 75. Accordingly, it is possible to enhance the effect of preventing the bundled entry of the sheets P from unexpectedly occurring due to the holder 74 being pushed down too much.

  As mentioned above, although embodiment of this invention was described, this invention is not limited to the said embodiment, A various deformation | transformation is possible. For example, in the above-described embodiment, a flat friction pad is illustrated as the friction member 75. However, the friction member 75 is not limited to such a friction pad, and may be configured by a friction roller, a friction belt, or the like.

  In the above embodiment, the friction member 75 is urged toward the rotary conveying member 72 (the other side) by the separation pressure spring 76 as the urging means (first urging means). The rotary conveying member 72 may be urged toward the friction member 75 side (the other side) by the urging means. In the embodiment, the guide portion 77 is disposed on the holder holding member 73. However, the guide portion 77 is directly attached to the machine frame of the laser printer 100, which is an image forming apparatus, or any member fixed to the machine frame. It is good also as a structure.

1: Photoconductor (image carrier) 2: Charging device 3: Developing device 4: Developer cartridge 5: Fixing device 6: Paper discharge device 7: Sheet material separating and feeding device 8: Timing roller 71: Sheet material stacking portion 71a : Support shaft 71b: spring (third urging means) 72: rotary conveying member 73: holder holding member 75: friction member 76: separation pressure spring (first urging means) 77: guide portion 78: top portion of guide portion 79 : Upstream guide surface 80: Downstream guide surface 86H: (Second urging means)
94: Holder restriction part 100: Laser printer N: Separation nip part P: Sheet material (paper)

Japanese Utility Model Publication No. 7-13852 Japanese Patent No. 4054459

Claims (11)

A sheet material stacking unit capable of stacking the sheet material in a multi-layered manner in a state where the front end portion of the sheet material feeding direction is inclined downward;
A rotary conveying member that contacts the uppermost sheet material of the sheet material stacking unit and conveys the sheet material downward;
A friction member disposed below the rotary conveying member and forming a separation nip portion through which a sheet material passes between the rotary conveying member;
First biasing means for biasing the friction member or the rotary conveying member to the other side and applying a separation pressure to the sheet material sandwiched between the separation nip portions;
Between the separation nip portion and the sheet material stacking portion, the front end of the sheet material that is fixedly disposed at a position that does not overlap with the upstream extension region of the separation nip portion and that enters the separation nip portion A guide portion that abuts,
The friction member is supported on the holder, the holder is held movably by the fixedly held holder holding member via the first urging means, and the guide portion is formed separately from the holder holding member. The guide portion is selected by selecting an engagement portion that is detachably attached to the holder holding member via an engagement portion, and is arranged at a plurality of selectable positions. The sheet material separating and feeding device is characterized in that the position of the sheet material can be adjusted. A sheet material stacking unit capable of stacking the sheet material in a multi-layered manner in a state where the front end portion of the sheet material feeding direction is inclined downward;
A rotary conveying member that contacts the uppermost sheet material of the sheet material stacking unit and conveys the sheet material downward;
A friction member disposed below the rotary conveying member and forming a separation nip portion through which a sheet material passes between the rotary conveying member;
First biasing means for biasing the friction member or the rotary conveying member to the other side and applying a separation pressure to the sheet material sandwiched between the separation nip portions;
Between the separation nip portion and the sheet material stacking portion, the front end of the sheet material that is fixedly disposed at a position that does not overlap with the upstream extension region of the separation nip portion and that enters the separation nip portion A guide portion that abuts,
The friction member is supported on the holder, the holder is held movably by the fixedly held holder holding member via the first urging means, and the guide portion is formed separately from the holder holding member. The sheet material separating and feeding apparatus, wherein the separate guide portion is movable in a rotation axis direction of the rotary conveying member. A sheet material stacking unit capable of stacking the sheet material in a multi-layered manner in a state where the front end portion of the sheet material feeding direction is inclined downward;
A rotary conveying member that contacts the uppermost sheet material of the sheet material stacking unit and conveys the sheet material downward;
A friction member disposed below the rotary conveying member and forming a separation nip portion through which a sheet material passes between the rotary conveying member;
First biasing means for biasing the friction member or the rotary conveying member to the other side and applying a separation pressure to the sheet material sandwiched between the separation nip portions;
Between the separation nip portion and the sheet material stacking portion, the front end of the sheet material that is fixedly disposed at a position that does not overlap with the upstream extension region of the separation nip portion and that enters the separation nip portion A guide portion that abuts,
An upstream guide surface having a gradually narrowing width from the upstream side to the downstream side in the feeding direction is formed on the upstream side in the feeding direction at the top of the guide portion. A sheet material stacking unit capable of stacking the sheet material in a multi-layered manner in a state where the front end portion of the sheet material feeding direction is inclined downward;
A rotary conveying member that contacts the uppermost sheet material of the sheet material stacking unit and conveys the sheet material downward;
A friction member disposed below the rotary conveying member and forming a separation nip portion through which a sheet material passes between the rotary conveying member;
First biasing means for biasing the friction member or the rotary conveying member to the other side and applying a separation pressure to the sheet material sandwiched between the separation nip portions;
Between the separation nip portion and the sheet material stacking portion, the front end of the sheet material that is fixedly disposed at a position that does not overlap with the upstream extension region of the separation nip portion and that enters the separation nip portion A guide portion that abuts,
A sheet material separating and feeding device, wherein a downstream guide surface gradually narrowing from the downstream side to the upstream side in the feeding direction is formed on the downstream side in the feeding direction at the top of the guide portion.   5. The sheet material separating and feeding apparatus according to claim 1, wherein a pair of the guide portions are disposed on both sides of the friction member. 6.   6. The sheet material separating and feeding device according to claim 5, wherein the pair of guide portions are disposed at symmetrical positions with respect to a center in a rotation axis direction of the rotary conveying member.   An upstream guide surface is formed on the upstream side in the feeding direction of the top portion of the guide portion, and an angle formed by the upstream guide surface and the uppermost sheet material stacked on the sheet material stacking portion is 90 ° or more and 180 °. The sheet material separating and feeding device according to any one of claims 1 to 4, wherein the sheet material separating and feeding device is at most °.   A downstream guide surface is formed downstream of the top of the guide portion in the feeding direction, and an angle formed between the downstream guide surface and the surface of the friction member from the separation nip portion toward the downstream end in the feeding direction of the friction member. The sheet material separating and feeding device according to any one of claims 1 to 4, wherein the sheet material separating and feeding device is at least 0 ° and at most 90 °.   The friction member is supported on the holder, the holder is movably held by a fixedly arranged holder holding member via the first urging means, and the guide portion is integrally formed with the holder holding member. The sheet material separating and feeding device according to claim 3 or 4, wherein the sheet material separating and feeding device is provided. Image forming apparatus comprising at least a conveying device that conveys a sheet material, an image forming device that forms an image on the sheet material conveyed by the conveying device, and a discharge device that carries the sheet material on which the image is formed out of the apparatus an apparatus, wherein the conveying device, an image forming apparatus characterized by having a sheet separating and feeding apparatus according to any one of claims 1 9. The image forming apparatus according to claim 10 , wherein the image forming apparatus is one of a copier, a printer, a facsimile machine, and an ink jet recording apparatus, or a composite machine that is a combination of two or more thereof.