JP4650640B2 - Paper feeder - Google Patents

Description

  The present invention provides a sheet feeding device that separates recording media (sheets) deposited on a sheet feeding cassette main body one by one by a sheet feeding roller and a plurality of elastic separation claw pieces and feeds them to an image recording unit. Is related to the configuration of

  2. Description of the Related Art Image recording apparatuses such as printers, copiers, and facsimile machines are provided with a sheet feeding device for separating and feeding sheets (recording medium) cut into the image recording unit one by one. Yes.

  A paper feeding device disclosed in Patent Document 1 includes a paper feeding cassette that stacks (stacks) a plurality of sheets (paper sheets) in a stacked state, and a paper feeding arm that is vertically swingable and disposed above the paper feeding cassette. And a paper feed roller provided at the lower end of the paper. In addition, an inclined separation plate is provided at the downstream end of the sheet feeding cassette in the feeding direction, and a sheet feeding separation member is disposed at the center of the inclined separation plate in the left-right direction (sheet width direction). ing. This sheet feeding separating member is formed integrally with a base portion made of a metal plate, a claw-shaped protrusion, an arm portion that supports the protrusion from both sides, and the base portion, and is provided on the back surface of the inclined separation plate. The leaf springs for supporting the parts are formed by pressing at regular intervals along the sheet feeding direction. The claw-like protrusions are set so as to project a predetermined amount from a long long hole drilled along the feeding direction at the center of the inclined separation plate. Then, the sheet is fed by a sheet feeding roller that rotates while pressing the uppermost surface of the stacked sheets. At this time, the leading edges of the stacked sheets are engaged with the protrusions, the overlapping sheets are loosened, and only the uppermost sheet (paper) is separated and fed.

In Patent Document 2, a sheet feeding cassette body having an open top surface is provided that stores cut sheets in a substantially horizontal state. An inclined surface is provided at an end portion on the downstream side of the sheet feeding cassette body, and a sheet separation guide is provided on the inclined surface. A plurality of protrusions are formed on the surface of the paper separation guide. The protrusions are the highest at the bottom of the paper separation guide, and the height of the protrusions gradually decreases at regular intervals as it goes upward. In this way, the coefficient of friction with the sheet edge is set to gradually decrease from the bottom to the top. The protrusions are formed in a plurality of rows in the width direction of the sheet.
Japanese Patent Laying-Open No. 2005-247550 (see FIGS. 3 to 9) JP 2004-067389 A (see FIGS. 4 to 6)

  By the way, in a paper feeding device provided with a paper feeding roller at the lower end of a paper feeding arm having a predetermined length and having a pendulum type paper feeding roller that swings up and down around the base end of the paper feeding arm, Thus, the paper feeding operation is performed. That is, when the sheet feeding roller rotates while pressing the uppermost sheet stacked on the sheet feeding cassette, only the uppermost sheet is separated by the cooperative action with the protrusions (protrusions). It is fed. In that case, the conveyance force by the paper feed roller, that is, the picking force (force in the direction parallel to the surface of the sheet) is the pressing force (force perpendicular to the surface of the sheet) on the uppermost layer by the paper feed roller. The value obtained by multiplying the friction coefficient for the sheet is the value obtained by subtracting the frictional force between the uppermost sheet and the adjacent lower layer sheet. Further, the pressing force increases as the depression angle between the arm and the uppermost sheet increases. In other words, the pressing force is small when the sheet stacking amount is large (when the stacking height is high), and the pressing force is large when the sheet stacking amount is small (when the stacking height is low). The frictional force between the uppermost sheet and the adjacent lower layer sheet does not fluctuate much even if the stack height of the sheet changes.

  Accordingly, the conveyance force by the paper feed roller, that is, the picking force (force in the direction parallel to the surface of the sheet) is small when the sheet stacking amount is large (when the stacking height is high), and when the sheet stacking amount is small. It increases when the deposition height is low. On the other hand, if the conveying force by the sheet feeding roller is too larger than the resistance force at the time of separating action by the projection (part) on the surface of the inclined separating plate (sheet separating guide), a plurality of sheets are fed at once. A so-called double feed phenomenon occurs. Therefore, this phenomenon is likely to occur when the amount of stacked sheets is small (when the stacking height is low). On the contrary, if the resistance force at the time of the separation action by the protrusion (part) is too large than the conveying force by the sheet feeding roller, sheet conveyance becomes impossible (so-called idle feeding state).

  However, in the configuration of Patent Document 1, the claw-like protrusions protruding from the surface of the inclined separation plate are in a row, and the amount of protrusion is not considered.

  On the other hand, in Patent Document 2, the protrusion height of the protrusion gradually decreases at regular intervals as it goes upward, and the friction coefficient gradually decreases as it goes from bottom to top (that is, during the separation operation). It is proposed to gradually reduce the resistance as you go up.

  However, in Patent Document 2, a plurality of protrusions are integrally formed on the surface of a flat sheet separation guide (material is unknown), and each protrusion has no elasticity. There was a problem that the separation performance could not be kept constant for a long time.

  SUMMARY OF THE INVENTION An object of the present invention is to solve the above-described problems, and to provide a paper feeding device that can reliably feed a recording medium to an image recording unit and that does not cause idle feeding. Is.

In order to achieve the above object, a paper feeding device according to a first aspect of the present invention includes a cassette body having an open top surface capable of accommodating a sheet-like recording medium in a stacked state, and the stacked uppermost layer covering. Paper feed roller means for feeding a recording medium, and a recordable recording medium provided at the downstream end of the cassette body in the feeding direction of the recording medium so as to extend perpendicular to the feeding direction An inclined separation plate provided up to a position higher than the maximum height position of the medium, and a plurality of separation claw pieces attached to the inclined separation plate and arranged at appropriate intervals along the feeding direction of the recording medium A sheet feeding device for separating and feeding recording media one by one by cooperation of the sheet feeding roller means and the separation claw piece,
The inclined separation plate is provided with a window hole for projecting a tip protruding portion of each separation claw piece to the recording medium contact surface side of the inclined separation plate,
The tip protrusion of each separation claw piece is bent to extend toward the feed downstream side with respect to the surface of the inclined separation plate,
The acute angle depression angle between the tip protrusion of the separation claw piece arranged on the upstream side in the feeding direction and the contact surface of the inclined separation plate is arranged on the downstream side in the feeding direction. It is set larger than the depression angle on the acute angle side between the tip protruding portion of the claw piece and the contact surface of the inclined separation plate.

  According to a second aspect of the present invention, in the paper feeding device according to the first aspect, the number of the rows of the separation claw pieces is more arranged on the upstream side in the feeding direction than on the downstream side in the feeding direction. It is what.

  According to a third aspect of the present invention, in the paper feeding device according to the first or second aspect, the separation claw pieces in the row located upstream in the feeding direction among the rows of the separation claw pieces are They are arranged in a staggered manner with respect to the direction orthogonal to the feeding direction.

  According to a fourth aspect of the present invention, in the paper feeding device according to any one of the first to third aspects, the separation claw piece is formed in one separation body, and each separation body is a back surface of the inclined separation plate. It is provided so as to be detachable with respect to the side.

  According to a fifth aspect of the present invention, in the paper feeding device according to any one of the first to fourth aspects, the paper feeding roller means has a pair of left and right rollers, and the row of the separation claw pieces is It arrange | positions so that it may correspond between the arrangement | positioning intervals of a pair of left and right rollers.

  According to a sixth aspect of the present invention, in the paper feeding device according to the fourth or fifth aspect, the separator is made of a flat metal plate, an arm portion extending from the main body portion, and a free standing up from the arm portion. The separation claw piece whose end side can come into contact with the recording medium and the elasticity applying piece extending from the main body portion.

  According to a seventh aspect of the present invention, in the paper feeding device according to any one of the fourth to sixth aspects, an accommodation portion that accommodates the separator is formed on a back surface of the inclined separation plate. The separator is supported by a support inserted from the back side so as not to drop off.

  According to the first aspect of the present invention, the separation is such that the leading end protrudes from the recording medium contact surface of the feeding roller means and the inclined separation plate on the downstream side in the feeding direction of the recording medium (paper) of the cassette body. When the paper is fed in cooperation with the claw piece, an acute angle side between the tip protruding portion of the separation claw piece arranged on the upstream side in the feeding direction and the contact surface of the inclined separation plate is provided. Since the depression angle is set to be larger than the depression angle on the acute angle side between the tip protruding portion of the separation claw piece disposed on the downstream side in the feeding direction and the contact surface of the inclined separation plate, The paper is fed by the paper feed roller attached to the lower end of the paper feed arm that swings up and down around the base end (upper end) when the amount of paper accumulated on the upstream side in the feeding direction is small. The feeding resistance force at the location of the separation claw piece on the inclined separation plate is increased. , The tip portions of a plurality of sheets of paper separating (loosening) tighten not ensure action, it is possible to reduce the double feeding phenomenon of the paper.

  On the other hand, on the downstream side in the feeding direction, that is, on the side far from the bottom plate of the cassette body, that is, when the amount of paper accumulated on the cassette body is large, the tip protrusions of the separation claw pieces and the inclined separation plates Since the depression angle on the acute angle side with the abutting surface is small, it is possible to limit the feeding resistance force at the portion of the separation claw piece in the inclined separation plate so as not to be too large, and it is possible to reduce the paper feed phenomenon.

  According to the invention of claim 2, by increasing the number of rows of separation claw pieces in correspondence with the upstream side in the feeding direction, and accordingly when the amount of accumulated paper on the cassette body is small, Multiple sheets with a sheet feeding roller attached to the lower end of the sheet feeding arm that swings up and down around the base end (upper end) to increase the feeding resistance force at the separation claw piece at the inclined separation plate It is possible to reduce the double feeding phenomenon of the sheet by reliably leveling the leading edge of the sheet. On the other hand, by reducing the number of separation claw strips on the downstream side in the feeding direction, that is, on the side far from the bottom plate of the cassette body, that is, when the amount of paper accumulated on the cassette body is large, the inclined separation plate In this case, the feeding resistance force at the portion of the separation claw piece is limited so as not to be too large, and the paper idle feeding phenomenon can also be reduced.

  According to the invention described in claim 3, among the rows of the separation claw pieces, the separation claw pieces in the row located on the upstream side in the feeding direction are staggered with respect to a direction orthogonal to the feeding direction. In addition to the operations and effects of the invention according to claim 1 or 2, the leading edges of the plurality of sheets to be fed have different heights from the bottom plate of the cassette body. Since the chance of colliding with a plurality of separation claw pieces increases, the effect of more reliably reducing the paper double feeding phenomenon can be achieved.

  According to the fourth aspect of the present invention, the separation claw piece is formed in one separation body, and each separation body is detachably provided on the back surface side of the inclined separation plate. When a plurality of rows of separation claw pieces are integrally formed on one separator in this way, the arrangement relationship of the separation claw pieces can be set with high accuracy without any variation, and the separation and feeding operation of the paper can be further ensured. it can.

  According to the fifth aspect of the present invention, since the row of separation claw pieces is arranged so as to correspond to the arrangement interval between the pair of left and right rollers in the paper feed roller means, Therefore, it is possible to effectively prevent the feeding resistance force due to the separation claw pieces from being concentrated on the central portion in the width direction of the paper to be skewed. In addition, since the buckling phenomenon is less likely to occur between the sheet feeding roller and the separation claw piece, the double feeding phenomenon is also less likely to occur.

  According to a sixth aspect of the present invention, the separator is made of a flat metal plate, and the separation is such that the arm portion extending from the main body portion and the free end side standing from the arm portion can contact the recording medium. It consists of a claw piece and an elasticity imparting piece extending from the main body portion.

  Therefore, after punching the arm part, the separation claw piece, and the elasticity imparting piece from the metal plate, the separation body can be easily formed by performing a predetermined bending process.

  According to the seventh aspect of the present invention, the rear surface of the inclined separation plate is formed with a housing portion for housing the separated body, and the separating body cannot be removed by the support body inserted from the rear surface side of the housing portion. Therefore, there is an effect that the assembling work of the separated body can be performed extremely easily. In addition, there is an effect that it is easy to incorporate the separation pawl pieces so that the separation amount of the separation body becomes a predetermined value.

  Hereinafter, specific embodiments of the present invention will be described with reference to the drawings. 1 is a perspective view of an image recording apparatus equipped with an ink jet recording head of the present invention, FIG. 2 is a schematic side sectional view, FIG. 3 is a perspective view of a cassette body and paper feed roller means, and FIG. FIG. 5 is a front view of the first embodiment of the separation claw piece, FIG. 6A is a cross-sectional view taken along line VIa-VIa in FIG. 4, and FIG. 6B is FIG. FIG. 7 is an enlarged sectional view taken along line VII-VII of FIG. 5, FIG. 8 is a front view of the second embodiment of the separation claw piece, and FIG. 9 is the first and second embodiments. FIG. 10 is a front view of a third embodiment of the separation claw piece, and FIG. 11 is an arrangement relationship between the separation claw piece and the paper feed roller in the third embodiment. It is explanatory drawing which shows.

  The image recording apparatus 1 according to the present embodiment is an application of the present invention to a multi-function device (MFD) having a printer function, a copy function, a scanner function, and a facsimile function. As shown in FIGS. 1 and 2, the image recording apparatus 1 includes a housing 2 made of a synthetic resin injection-molded product.

  An image reading device 12 for a copy function or a facsimile function is disposed on the upper portion of the housing 2. The image reading device 12 is configured to be vertically openable and closable with respect to one side end of the housing 2 via a pivot portion (not shown). Further, the rear end of the document cover 13 that covers the upper surface of the image reading device 12 is attached to the rear end of the image reading device 12 so as to be openable and closable about a pivot (not shown).

  On the upper side of the housing 2, an operation panel unit 14 including various operation buttons and a liquid crystal display unit is provided in front of the image reading device 12. An upper surface of the image reading device 12 is provided with a placement glass plate (not shown) on which an original cover body 13 can be opened to place an original and an original is placed on the lower side. A contact image sensor (CIS) (not shown) is provided so as to be capable of reciprocating along a guide shaft extending in a direction perpendicular to the paper surface of FIG. 2 (X-axis direction in FIG. 1).

  In the present embodiment, four ink cartridges for each color of black (Bk), cyan (C), magenta (M), and yellow (Y) are stored as cartridges for individual colors in an ink storage unit (not shown). Yes. Each ink cartridge and the recording head 4 in the recording unit 7 (corresponding to the image recording unit in the claims) are always connected by a flexible ink supply pipe. With this configuration, each color ink is supplied from each ink cartridge to the recording head 4.

  A cassette body 3 that can be inserted and removed from an opening 2a on the front side (left side in FIG. 2) of the housing 2 is disposed at the bottom (bottom) of the housing 2. In the present embodiment, the cassette body 3 is a recording medium (cut sheet), for example, a sheet P cut into A4 size, letter size, legal size, postcard size, etc. A plurality of sheets are stacked (deposited) so as to be accommodated so as to extend in a direction perpendicular to the axial direction (in FIG. 2, a direction perpendicular to the paper surface).

  As shown in FIG. 3, the cassette body 3 in the paper feeding device is provided with a bottom plate 31 on which the paper P is placed, and on both sides of the bottom plate 31 along the feeding direction (arrow A direction, see FIG. 2). Side plates 32, 32 are erected. In the present embodiment, the paper discharge tray 33 partially covers the both side plates 32 and 32 so as to cover a part of the upstream side in the feeding direction (arrow A direction) of the paper P placed on the bottom plate 31. Attached across the. In order to easily store the paper P in the bottom plate 31 of the cassette main body 3, the paper discharge tray 33 is mounted on the cassette main body 3 so as to be openable and closable around a rotation shaft (not shown).

  Further, on the downstream side in the feeding direction (arrow A direction) of the bottom plate 31, the paper width for setting the paper P symmetrically with respect to the center in the width direction of the cassette body 3 and guiding the transport direction of the paper P is provided. A guide (not shown) is arranged to be movable in conjunction with the left-right direction (the width direction of the paper P: the X-axis direction).

  On the back side of the cassette body 3 (the right side in FIG. 2 and the left side in FIG. 3), a separation inclined plate 8 having a separating body 11 for separating the leading edge of the paper P one by one is detachably fixed. ing. Further, on the housing 2 side, as will be described later, a base end portion of the paper feed arm 6a in the paper feed roller means 6 is mounted so as to be rotatable in the vertical direction around the drive shaft 34. A pair of left and right paper feed rollers 6b provided at the tip of the paper feed arm 6a is driven by a driving force from a drive source (not shown) between the drive shaft 34 and a gear transmission mechanism provided in the paper feed arm 6a. (See FIGS. 3 and 4).

  As described above, the sheet feeding roller unit 6 includes the sheet feeding arm 6a, the pair of sheet feeding rollers 6b, and the drive shaft 34. A pair of left and right paper feed rollers 6b in which a high friction coefficient member such as rubber is wound around the outer periphery of the free end (lower end) of the synthetic resin frame-like paper feed arm 6a is rotatable. Is pivotally supported. Further, the base end portion of the paper feed arm 6a is rotatably supported by the tip portion of the synthetic resin drive shaft 34. The driving force transmitted from the drive source (not shown) to the drive shaft 34 is transmitted to the paper feed roller 6b through a gear transmission mechanism including a plurality of gear trains provided in the paper feed arm 6a. The paper feed roller 6b rotates in a predetermined direction (the direction in which the paper P accommodated in the cassette body 3 is conveyed). The gear transmission mechanism includes a gear that rotates integrally with the drive shaft 34, a planetary gear that is pivotally supported at the tip of a planetary arm that is rotatably fitted to the drive shaft 34, and that meshes with the gear described above. The planetary gear is composed of a plurality of intermediate gears that transmit power to the gear formed on the side of the paper feed roller 6b.

  The paper P, which is a recording medium accumulated and accommodated in the cassette body 3, is separated from the uppermost layer one by one by the cooperation of the paper feed roller 6b and the separator 11 (described in detail later) in the separation inclined plate 8. Can be fed. The separated paper P is transported to the recording unit 7 provided on the upper side (high position) of the cassette body 3 via a transport path 9 including a lateral U-turn path. The conveyance path 9 is formed in a gap between a first conveyance path body that forms the outer peripheral side of the U-turn shape and a second conveyance path body that is a guide member that forms the inner peripheral side. In the transport path 9, center alignment in which the center line in the width direction of the paper P is aligned with the center line (not shown) in the width direction (hereinafter simply referred to as the width direction) orthogonal to the transport direction, The paper P is configured to be conveyed.

  The recording unit 7 is fixedly supported by a box-shaped main frame 21 and a pair of left and right side plates thereof, and is a horizontally long plate-shaped first and second guide members (in the main scanning direction of the recording head 4) that extend in the X-axis direction. (Not shown). The carriage 5 on which the ink jet recording head 4 is mounted in the recording unit 7 is slidably supported (mounted) across the upstream first guide member and the downstream second guide member in the paper transport direction. A reciprocating movement is possible in the main scanning direction (X-axis direction).

  In order to reciprocate the carriage 5, a timing belt (not shown) is extended on the upper surface of the second guide member arranged on the downstream side in the paper transport direction (arrow A direction) so as to extend in the main scanning direction (X-axis direction). A CR (carriage) motor (not shown) for driving the timing belt is fixed to the lower surface of the second guide member.

  A flat platen 26 extending in the X-axis direction so as to face the lower surface of the recording head 4 in the carriage 5 is fixed to the main frame 21 between the first and second guide members.

  On the upstream side of the platen 26 in the conveying direction, a driving roller 27a and a driven roller below the driving roller 27a are disposed as conveying (registration) rollers for conveying the paper P to the lower surface of the recording head 4. ing. Further, on the downstream side in the transport direction of the platen 26, a paper discharge roller 28a that is driven to transport (discharge) the recorded paper P to the paper discharge tray 33, and a paper discharge roller 28a side facing this. And a spur roller biased by (see FIG. 2).

  Next, the configuration of the inclined separation plate 8 and the separator 11 will be described. As shown in FIGS. 3 to 7, the sheet separating inclined separating plate 8 is detachably disposed on the back side (left end in FIG. 3) end of the cassette body 3. 8 and the cassette body 3 are synthetic resin injection molded products. The inclined separation plate 8 has a continuous plate shape. The inclined separation plate 8 is formed in a convex curved shape in plan view so as to protrude at the center in the width direction (X-axis direction) of the paper P and to recede toward the left and right ends in the width direction of the paper P. Yes. Further, a separator 11 in which a separation claw piece (claw-like elastic body) 36 that is in contact with the leading edge of the paper P and promotes separation is integrally formed at the center of the inclined separation plate 8 is inclined. It can be attached from the back of the separation plate 8.

  On the back side of the inclined separation plate 8, a plurality of back support portions 38 having a substantially triangular shape in side view are provided at appropriate intervals along the X-axis direction. The back support 38 is disposed in contact with the back plate 37 in the cassette body 3 when the inclined separation plate 8 is mounted on the cassette body 3. Therefore, as described above, the inclined separation plate 8 is maintained in a convex curved shape in a plan view and is also restricted from being deformed when the paper P is conveyed.

  Further, each separation claw piece 36 in the separator 11 to be described later faces the contact surface side of the paper P from the back side at the center of the longitudinal direction (X-axis direction, width direction of the paper P) of the inclined separation plate 8. A plurality of window holes 44 are provided along the feeding direction of the paper P (the direction of arrow A, see FIGS. 4, 5, 7, etc.). These window holes 44 are opened in two rows and at an appropriate predetermined interval (an interval substantially equal to the arrangement interval of the separation claw pieces 36) (see FIGS. 4 and 7). The separation claw pieces 36 protrude from the window holes 44 toward the contact surface (front surface) side of the sheet P of the inclined separation plate 8. Accordingly, a portion (bridge portion) 50 between adjacent small window holes 44 is integral with the inclined separation plate 8. A mounting case 46 for supporting the separator 11 is integrally formed on the back side of the inclined separator 8 so as to surround all the window holes 44. The mounting case 46 can accommodate a box-like support member 45 (support) made of synthetic resin, which will be described later. The separator 11 is fixedly supported by the mounting case 46 and the support member 45 (see FIGS. 6A and 6B).

  Each separation claw piece 36 has a base portion 36a standing at a right angle from the arm portion 40, and tilts downward from the base portion 36a toward the downstream side in the paper feeding direction (contact of the paper P with the inclined separation plate 8 (table)). And a tip protruding portion (also referred to as a free end side) 36b bent so as to be inclined obliquely upward with respect to the surface (see FIG. 7). Then, as shown in FIG. 7, the leading end protrusion 36b of the separation claw piece 36 disposed on the upstream side in the feeding direction (the side close to the bottom plate 31 of the cassette body 3, corresponding to the case where the amount of accumulated paper P is small). And the angle of depression on the acute angle side between the contact surface (front surface) of the sheet P of the inclined separation plate 8 is β1. Furthermore, the sheet of the leading protrusion 36b and the inclined separation plate 8 in the separation claw piece 36 disposed on the downstream side in the feeding direction (the side far from the bottom plate 31 of the cassette body 3 and corresponding to the case where the amount of accumulated paper P is large). The angle of depression on the acute side with the contact (front) surface of P is β2. In the present invention, the depression angle β1 is set larger than the depression angle β2. In the embodiment, the depression angle β2 is about 30 degrees, and the depression angle β1 is set to about 40 degrees. Accordingly, in FIG. 7, the included angle θ1 formed between the upper surface of the bottom plate 31 corresponding to the included angle β1 and the tip protruding portion 36b is about 70 degrees, and the upper surface of the bottom plate 31 corresponding to the included angle β2 is formed between the upper end protruding portion 36b. The depression angle θ2 is about 80 degrees.

  In this way, by increasing the depression angle β1, it swings up and down around the base end (upper end) when the amount of paper P accumulated on the upstream side in the feeding direction, and hence the amount of paper P on the cassette body 3 is small. The sheet feeding roller 6b attached to the lower end of the sheet feeding arm 6a can increase the feeding resistance force of the sheet P at the separation claw piece 36 in the inclined separation plate 8. For this reason, even when the accumulation amount of the paper P on the cassette body 3 is small, it is possible to reduce the double feeding phenomenon of the paper P by reliably leveling the leading edge of the plurality of papers P. it can.

  On the other hand, by making the depression angle β2 smaller than β1, it swings up and down around the base end (upper end) when the amount of paper P deposited on the cassette body 3 is large downstream in the feeding direction. The sheet feeding roller 6b attached to the lower end of the sheet feeding arm 6a can limit the sheet P so that the feeding resistance force at the separation claw piece 36 in the inclined separation plate 8 is not too large. The phenomenon can be reduced.

  A bearing portion 48 of a pair of rotatable rollers 47 for smooth feeding operation of the paper P is provided on the rear side of the inclined separation plate 8 on the outer side in the width direction of the paper P than the mounting case 46. A hole 49 is formed so that a part of the circumferential surface of each roller 47 faces the surface of the inclined separation plate 8 (see FIGS. 4 and 6A).

  In the present invention, the number of rows of the separation claw pieces 36 is the upstream side in the feeding direction (corresponding to the side closer to the bottom plate 31 of the cassette body 3, and accordingly, when the amount of paper P deposited on the cassette body 3 is small). And a small amount on the downstream side in the feeding direction (the side far from the bottom plate 31 of the cassette main body 3, and accordingly corresponds to the case where the amount of paper P deposited on the cassette main body 3 is large). In short, the number of rows of the separation claw pieces 36 is more arranged on the upstream side in the feeding direction than on the downstream side in the feeding direction.

  In the first embodiment (see FIG. 5), the second embodiment (see FIG. 8), and the third embodiment (see FIG. 10), the number of rows of separation claw pieces 36 is two on the upstream side in the feeding direction. And one row on the downstream side in the feeding direction. However, the number of rows of the separation claw pieces 36 is not limited to this, and the separation claw pieces 36 need only be arranged more upstream in the feeding direction than in the feeding direction.

  In this way, the base end (upper end) is increased by increasing the number of rows of the separation claw pieces 36 corresponding to the upstream side in the feeding direction, and accordingly, when the amount of paper P deposited on the cassette body 3 is small. The sheet feeding roller 6b mounted on the lower end of the sheet feeding arm 6a that swings up and down around the sheet feed P increases the feeding resistance force at the position of the separation claw piece 36 on the inclined separation plate 8 to It is possible to reduce the double feeding phenomenon of the paper P by reliably leveling the unwinding action of the leading end of the paper P. On the other hand, the number of rows of separation claw pieces 36 is reduced on the downstream side in the feeding direction, that is, on the side far from the bottom plate 31 of the cassette body 3, that is, when the amount of paper P accumulated on the cassette body 3 is large. As a result, the feeding resistance force at the separation claw piece 36 in the inclined separation plate 8 is limited so as not to be too large, and the paper feeding phenomenon of the paper P can be reduced.

  The separation claw pieces 36 are formed on one or a plurality of separation bodies 11, and each separation body 11 is detachably provided on the back surface side of the inclined separation plate 8. That is, as described above, the separating body 11 is accommodated in the open-back mounting case 46 (corresponding to the accommodating portion in the claims). Then, by attaching a detachable box-like support member 45 (corresponding to the support in the claims) from the back side of the mounting case 46, the separator 11 is fixed and supported so as not to fall off (FIG. 6A). ) And FIG. 6B). When there are a plurality of separators 11, the attachment cases 46 are separately formed on the back side of the inclined separation plate 8 for each separator 11, and the support member 45 is arranged for each attachment case 46.

  Next, the configuration of the separator 11 according to the first embodiment will be described in detail. As shown in FIGS. 5 to 7, the separating body 11 is made of a metal plate as an elastic body such as stainless steel. The separating body 11 has a mountain-shaped (inverted V-shaped) arm portion 40 extending from a flat main body portion (base portion) 39, and stands up (cuts and raises) from the center portion of the arm portion 40, and the free end side is the paper P. A claw-shaped separation claw piece 36 that can be contacted, and an elasticity applying piece (plate spring part) 41 that extends outward from the main body portion 39 are provided.

  In the first embodiment, the width of the lower body portion (base portion) 39 is large. The arm portion 40 and the separation claw pieces 36 are formed on the main body portion (base portion) 39 in two rows on the left and right sides and in parallel with the left and right at regular intervals in the vertical direction. 41 protrudes diagonally upward. The left and right width dimensions of the upper main body portion 39 are small, and the arm portions 40 and the separation claw pieces 36 are formed in one row at regular intervals along the feeding direction at the central portion of the width. Similarly, the elasticity imparting pieces 41 protrude obliquely upward at both the left and right ends of the upper body portion 39.

  Each separation claw piece 36 is inclined so as to incline and incline toward the downstream side in the paper feeding direction of the paper P with the base portion 36a standing at right angles from the arm portion 40 (inclined obliquely upward with respect to the surface of the inclined separation plate 8). And a tip protruding portion (also referred to as a free end side) 36b that is bent. If comprised in this way, a isolation | separation body can be easily formed by punching out from a metal plate and passing through a predetermined bending process after that.

  The bent portions of the base portion 36a and the tip protruding portion 36b are set so as to be within the thickness of the inclined separation plate 8. As a result, the leading edge of the paper P to be fed does not collide with the base portion 36a and the bent portion (if it collides with this portion, the resistance force becomes too large to be fed), and an oblique angle toward the leading end portion 36b side. Touch with. A plurality of sheets P to be fed are loosened by the resistance force against the leading edge of the sheet P at this time, and only the uppermost sheet P is separated and fed.

  The free end sides of the left and right elasticity imparting pieces 41 are respectively supported by the end surfaces of the upper and lower longitudinal rib portions 45a, 45b, and 45c formed on the inner surface of the box-shaped support member 45 (FIG. 5). 6 (a) and 6 (b)), the entire main body portion 39 (full length) can be elastically biased in contact with the back surface of the inclined separation plate 8 without a gap.

  As described above, when the plurality of rows of separation claw pieces 36 are integrally formed on one separation body 11, the number of parts can be reduced compared to the case where only one row of separation claw pieces 36 is formed on one separation body 11. Can be reduced. In addition, a plurality of rows of separation claw pieces 36 can be formed close to (in proximity to) the center of the width of the main body portion (base portion) 39 of one separation body 11, and the shape of the separation body 11 can be made compact. Can be. When a plurality of rows of separation claw pieces 36 are integrally formed on one separation body 11, variations in the quality of the separation claw pieces 36 with respect to the plate thickness, material (spring constant), etc. of the separation body 11 are reduced. This can further reduce the double feed phenomenon and the idle feed phenomenon of the paper P.

  Among the rows of separation claw pieces 36, the separation claw pieces 36 in a plurality of rows located upstream in the feeding direction are fed in the first embodiment (see FIG. 5) and the third embodiment (see FIG. 10). They are arranged in parallel to the direction orthogonal to the direction, and in the second embodiment (see FIG. 8), they are arranged in a staggered manner. In this way, by arranging the plurality of rows of separation claw pieces 36 on the side close to the bottom plate 31 of the cassette body 3 in parallel or staggered, the leading edges of the plurality of sheets of paper P to be fed are Since the opportunity to collide with a plurality of separation claw pieces 36 having different heights increases from the above, it is possible to further reduce the double feeding phenomenon of the paper P.

  In the second embodiment (see FIG. 8), except that the two rows of separation claw pieces 36 located below the separator 11 (upstream in the feeding direction) are arranged in a staggered manner, Since it is exactly the same as the form (configuration) of one embodiment, the same reference numeral is given to the same configuration, and the detailed description is omitted.

  In the third embodiment (see FIG. 10), two rows of separation claw pieces 36 located on the lower side of the separation body 11 (upstream in the feeding direction) are formed symmetrically in the wide width direction of the main body portion 39. On the other hand, one row of separation claw pieces 36 located on the upper side of the separation body 11 (on the downstream side in the feeding direction) is formed at the center in the width direction of the main body portion 39, and the two rows of the lower row are separated. It is located between the separation claw pieces 36. With this configuration, both the upper and lower separation claw pieces 36, the main body portion 39, the arm portion 40, the elasticity applying piece 41, and the like are formed symmetrically. 8, the separation feeding operation for the paper P arranged in the left and right center can be in a balanced state.

  The row of separation claw pieces 36 corresponds to the interval L1 between the pair of left and right paper feed rollers 6b in the paper feed roller means 6 (see FIG. 9 and FIG. 11), or is fed by each paper feed roller 6b. It sets so that it may be arrange | positioned in the position facing a sending action part. By configuring in this way, it is possible to effectively prevent the sheet P from being skewed due to the feeding resistance force by the separation claw pieces 36 being concentrated at the center in the width direction of the sheet P to be fed. Further, since the buckling phenomenon hardly occurs in the paper P between the paper feed roller 6b and the separation claw piece 36, the effect that the double feeding phenomenon hardly occurs (can be reduced) is achieved.

  In the above configuration, when the separating body 11 is inserted into the mounting case 46 from the back side of the inclined separating plate 8, the arm portions 40 are fitted into the window holes 44, and the support members 45 are fixed, the support members 45 are fixed. All the elasticity imparting sides (elastic feet) 41 of the separator 11 are supported. As a result, the main body portion 39 closely contacts the back side of the inclined separation plate 8, and each separation claw piece 36 protrudes by a predetermined amount toward the contact (front) surface side of the sheet P of the inclined separation plate 8, and the protruding amount (See FIGS. 6 (a) and 6 (b)).

  The inclined separation plate 8 is locked from above into the locking groove of each back support 38 in the back plate 37 of the cassette body 3, while the back of the tilt separation plate 8 is brought into contact with the inclined surface of each back support 38. When arranged, the surface of the inclined separation plate 8 (the surface facing or abutting against the leading edge of the paper P) also projects at the center in the longitudinal direction (X-axis direction, width direction of the paper P), and the width of the paper P It forms in a convex curve shape (bow shape) in plan view so as to move backward (away from the leading edge of the paper P) as it goes to the left and right ends of the direction. In this case, the central portion (the portion having the window hole 44) in the longitudinal direction of the inclined separation plate 8 has the largest bending stress and bending deformation, but a series of window holes elongated vertically so as to surround the plurality of separation claw pieces 36. Compared with the structure which perforates | pierces, like the present invention, the bridge part 50 of the several places between the adjacent small window holes 44 reinforces (increases the bending rigidity of the center part of the longitudinal direction of the inclination separation plate 8). ) Can contribute. Accordingly, the central portion in the longitudinal direction of the inclined separation plate 8 (the bridge portion 50 corresponding to the window hole 44) does not warp so as to suddenly protrude toward the surface side, and therefore, by a predetermined protrusion amount as designed, The separation claw piece 36 can be protruded, and the action of separating and feeding the fed sheets P one by one can be ensured.

  Needless to say, each of the above embodiments (inventions) can also be applied to an image recording apparatus in which the cassette body 3 is arranged in multiple stages.

1 is a perspective view of an image recording apparatus provided with an ink jet recording head of the present invention. It is a schematic sectional side view of an image recording device. It is a perspective view of a cassette main body and paper feed roller means. It is a perspective view of an inclination separation plate and a paper feed roller means. It is a front view of a separated body. (A) is a sectional view taken along line VIa-VIa in FIG. 4, and (b) is a sectional view taken along line VIb-VIb in FIG. FIG. 7 is an enlarged sectional view taken along line VII-VII in FIG. 5. It is a front view of 2nd Embodiment of a separation body. It is explanatory drawing which shows the arrangement | positioning relationship between the separator and paper feed roller in 1st Embodiment and 2nd Embodiment. It is a front view of 3rd Embodiment of a separation body. It is explanatory drawing which shows the arrangement | positioning relationship between the separator and paper feed roller in 3rd Embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Image recording apparatus 3 Cassette main body 6 Paper feed roller means 6a Paper feed arm 6b Paper feed roller 8 Inclined separation plate 11 Separation body 36 Separation claw piece 39 Main body part 40 Arm part 41 Elastic leg 44 as elastic provision piece Window hole 47 Roller 50 Bridge part

Claims (7)

A cassette body having an open top surface capable of accommodating sheet-like recording media in a stacked state; paper feed roller means for feeding the deposited uppermost recording medium; and the recording medium in the cassette body. An inclined separating plate provided at a downstream end in the feeding direction so as to extend perpendicular to the feeding direction and to a position higher than the maximum height position of the recordable recording medium, and the inclination A plurality of separation claw pieces attached to a separation plate and arranged at appropriate intervals along the feeding direction of the recording medium, and a recording medium by cooperation of the paper feed roller means and the separation claw pieces A sheet feeding device that feeds the sheets one by one,
The inclined separation plate is provided with a window hole for projecting a tip protruding portion of each separation claw piece to the recording medium contact surface side of the inclined separation plate,
The tip protrusion of each separation claw piece is bent to extend toward the feed downstream side with respect to the surface of the inclined separation plate,
The acute angle depression angle between the tip protrusion of the separation claw piece arranged on the upstream side in the feeding direction and the contact surface of the inclined separation plate is arranged on the downstream side in the feeding direction. A sheet feeding device, characterized in that it is set to be larger than a depression angle on an acute angle side between a tip projecting portion of the claw piece and the contact surface of the inclined separation plate.   2. The sheet feeding device according to claim 1, wherein the number of rows of the separation claw pieces is more arranged on the upstream side in the feeding direction than on the downstream side in the feeding direction.   The separation claw pieces in a row located upstream of the feeding direction among the rows of the separation claw pieces are arranged in a staggered manner with respect to a direction orthogonal to the feeding direction. Item 3. The sheet feeding device according to Item 1 or 2.   The said separation claw piece is formed in one separation body, and each separation body is provided so that attachment or detachment is possible with respect to the back surface side of the said inclination separation plate. The paper feeder described.   The sheet feeding roller means has a pair of left and right rollers, and the row of the separation claw pieces is arranged so as to correspond to the arrangement interval of the pair of left and right rollers. The sheet feeding device according to any one of 1 to 4.   The separation body is made of a flat metal plate, and includes an arm portion extending from a base portion, the separation claw piece whose free end side standing from the arm portion can come into contact with a recording medium, and an elasticity applying piece extending from the base portion. The sheet feeding device according to claim 4, wherein:   A housing part for housing the separator is formed on the back surface of the inclined separation plate, and the separator is configured to be supported so as not to fall off by a support body inserted from the back side of the housing part. The sheet feeding device according to claim 4, wherein

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