CN100379661C - image recording device - Google Patents

Abstract

An image recording apparatus includes an image recording unit, a conveyance channel, a feed cassette, a feed unit, and a separation unit. Stacked recording media can be accommodated in the feeder cassette. The feeding unit feeds the recording media stacked on the feeding cassette to the conveyance path. The separating unit separates the recording medium from the stacked recording medium, and conveys the separated recording medium upward to the conveyance path in cooperation with the feeding unit. The conveying channel comprises a conveying channel part which has a U-shaped plate part in a side view. The conveying path member includes a plurality of rollers provided at a central portion of the conveying path member in the width direction perpendicular to the conveying direction of the recording medium.

Description

image recording device

technical field

The present invention relates to a structure of an image recording apparatus having a U-shaped turning passage, which separates recording media (cut sheets or sheets) stacked substantially horizontally in a paper feeding cassette one by one, The separated recording medium is thereby fed to an ink jet type recording unit positioned above the paper feed cassette.

Background technique

There are various conventional image recording devices such as printers or facsimile machines. For example, JP2002-249248 A (see FIG. 1 ) discloses the following image recording device. A large number of sheets (recording media or cut sheets) are stacked approximately horizontally and accommodated in a sheet feeder cassette arranged at a lower portion of the main body (casing) of the image recording apparatus, movable back and forth (extractable). The paper feed roller is placed in the vicinity of the inclined separation portion at the front end of the paper feed cassette and on the upper surface of the paper feed cassette. In this image recording apparatus, after the sheet fed by the feed roller is guided upward by the inclined separation portion, the sheet is conveyed to a position below the recording head through a conveyance path including a reverse roller and a conveyance guide plate (conveyance path plate), where the conveyance roller is placed. The guide plate is made to face the outer periphery of the reverse roller. In side view, the transport guide plate has a substantially U-shaped portion. Subsequently, the paper is discharged to the front side of the main body of the image recording apparatus.

Contents of the invention

However, in order to drive the reverse roller in the structure of JP2002-249248 A, a power transmission system including a set of gears is required to transmit power from the drive motor to the reverse roller. In addition, the counter roller should have a larger diameter so as to follow the curved inner surface of the conveying guide plate. Therefore, there arises a problem that the structure of the image recording device becomes complicated and the overall height of the imaging device becomes high.

In addition, there is a problem when separating recording media one by one at the inclined separation plate at the front end of the paper feeder that its separation performance varies (unstable), specifically, when a large number of recording media are stacked on the feeder. The separation performance changes in the case of the case in the paper cassette and the case in which the stack height of the recording medium decreases as the image recording task progresses, or the difference in stiffness of the recording medium causes a change in the separation performance.

The present invention provides an image recording apparatus capable of reliably and stably feeding a recording medium, even the last recording medium, to a recording unit with a relatively simple structure.

According to one aspect of the present invention, the image recording device of the present invention comprises:

a subject;

an image recording unit, the image recording unit forms an image on the recording medium;

a delivery channel through which the recording medium is fed to the image recording unit, the image recording unit and the delivery channel being placed in the main body;

a feeding cassette which is placed in the lower portion of the main body and is placed under the image recording unit so as to be able to move back and forth, and the stacked recording media can be accommodated in the feeding cassette;

a feed roller that feeds the recording medium stacked on the feed cassette to the conveyance path; and

a separation unit placed at one end of the feeder cassette to separate the recording medium from the stacked recording medium, and to convey the separated recording medium upward to the conveyance path in cooperation with the feed roller, wherein:

The conveying channel comprises a conveying channel element having a U-shaped plate portion in a side view;

The conveying path member includes a plurality of rollers provided in a freely rotatable manner at a center portion of the conveying path member in a width direction perpendicular to a conveying direction of the recording medium,

arranging the plurality of rollers in a transport direction of the recording medium;

the plurality of rollers are always separated from the feed roller when the recording medium is fed to the recording unit; and

One roller located upstream in the conveying direction has a larger diameter than the other roller located downstream in the conveying direction.

According to this structure, since the plurality of freely rotatable small-diameter rollers are provided at the center portion in the recording medium width direction of the conveyance path member, which is U-shaped in a side view direction, the structure is compact and The recording medium can be conveyed to the recording unit smoothly and reliably.

According to an aspect of the present invention, the plurality of rollers may be arranged at predetermined intervals in the conveyance direction of the recording medium. The diameter of one roller located upstream in the conveying direction may be equal to or larger than the diameter of the other roller located downstream in the conveying direction.

According to this structure, in addition to the aforementioned advantages, the following advantages can be achieved. Since the diameter of one roller located upstream in the conveying direction is made larger, and the diameter of the rollers located downstream in the conveying direction is gradually reduced, the height at which the outer peripheral surfaces of these rollers protrude from the conveying passage member can be along the surface of the conveying passage member. decrease. In addition, it is also possible to greatly reduce the resistance generated when the leading edge of the recording medium transferred upward from the separation unit abuts against the outer peripheral surface of the roller. Thus, the recording medium can be easily and smoothly conveyed to the downstream side of the U-shaped conveying path member, which effectively prevents paper jams from occurring.

According to an aspect of the present invention, the diameter of each roller may gradually increase from an end portion of each roller toward a center portion of each roller.

In addition, according to an aspect of the present invention, corners of intersections between the outer peripheral surface of each roller and the end surface of each roller may be removed.

According to this structure, when the conveyed recording medium abuts against the outer peripheral surface of each roller, streaks are not generated on the surface of the recording medium (recording surface), so that it is difficult to deteriorate the quality of the recorded image in the recording unit.

According to an aspect of the present invention, the conveyance path member may further include an accommodating portion in which the roller and the shaft of the roller are accommodated while the accommodating portion exposes the roller and the shaft to the surface of the conveyance path member through which the recording medium passes. A cover member may be detachably placed on the surface of the conveyance path member through which the recording medium passes, thereby exposing at least a portion of each roller and covering the shaft of the roller.

According to this structure, troublesome work including placing and installing a plurality of rollers can be easily performed only by installing one cover, thereby preventing the shaft from coming off.

According to an aspect of the present invention, on the upstream side in the conveying direction of the recording medium, the surface of the conveying passage member on which the recording medium slides may be formed as a convex curved surface. The convex curved surface may protrude at a central portion of the conveying channel member in the width direction and gradually retract as approaching an end portion of the conveying channel member in the width direction.

According to this structure, since both end portions in the width direction of the recording medium conveyed along the conveyance path bent in a U-shape in side view are not in sliding contact with the conveyance path member or the rib, the conveyance resistance is reduced, and by This enables the recording medium to be transported smoothly and lightly.

According to an aspect of the present invention, the transport path member may further include a plurality of ribs protruding from the surface through which the recording medium passes. These ribs are elongated in the conveying direction of the recording medium, and are arranged at positions outside the rollers at predetermined intervals. Each rib has a cross section in the width direction of the recording medium in which each rib is inclined outward at an obtuse angle toward the outside in the width direction.

In addition, according to an aspect of the present invention, on the upstream side in the conveying direction of the recording medium, the surface over which the recording medium slides defined by the conveying passage member and the rib may be formed as a convex curved surface. The convex curved surface may protrude at a central portion of the conveying channel member in the width direction and gradually retract as approaching an end portion of the conveying channel member in the width direction.

According to the former structure, the plurality of ribs are arranged at predetermined intervals at positions outside the roller, the ribs have a cross section in the width direction of the recording medium, in which the ribs are formed at an angle to the width direction. Obtuse angles slope outward. Therefore, the recording medium is conveyed while the side edge of the recording medium in the width direction is placed on the gentle slope of the rib. In this way, it is possible to prevent the recording medium from traveling in a curved manner, thereby also avoiding the occurrence of paper jams.

According to an aspect of the present invention, the separation unit may include a separation member at a center portion in a width direction, the separation member abutting on leading edges of the plurality of recording media, thereby separating the recording media one by one. The separating unit may further include a plate member having a convex curved surface protruding toward a leading edge of the recording medium in the vicinity of the separating member. The inclined separation plate may retract from the leading edge of the recording medium as it approaches the end of the recording medium in the width direction.

According to this structure, when the leading edge of the recording medium in the width direction first abuts against the separating member, the separating member provided in the separating unit can reliably perform the operation of separating the recording media one by one, wherein the separating member is positioned at The separation unit is at the center portion in the width direction.

According to an aspect of the present invention, a rib may be integrally formed with the base portion of the separation unit so as to close a gap formed between the bottom plate of the feeder cassette and the base portion of the separation unit having a convex curved surface.

According to this structure, when recording media with a small stack amount are fed near the bottom plate, the presence of the rib allows the leading edge of the recording medium to be reliably guided to the upper side of the separation unit without the leading edge of the recording medium fitting into the gap middle.

According to an aspect of the present invention, a friction member may be placed at the bottom plate of the feed box facing the feeding unit. An upward guide portion may be placed on the bottom plate on the downstream side of the friction member in the conveying direction of the recording medium and between the base portion of the separation unit and the friction member. The upward guide portion is lower on the side of the friction member and gradually becomes higher toward the side of the base portion.

According to this structure, when recording media with a small stacked amount are fed near the bottom plate, the leading edge of the recording medium can be reliably guided upward along the upward guiding portion. This makes it possible to reliably guide the recording medium to the upper side of the separating unit without the leading edge of the recording medium fitting into the gap.

According to an aspect of the present invention, the separation unit may include an inclined plate. On a recording medium receiving surface of the conveying passage member, an upper edge of the inclined plate may extend to a position higher than a lower edge of the conveying passage member so that the inclined plate partially overlaps the conveying passage member.

According to this structure, even if the recording medium is stacked close to the maximum amount, the recording medium can be smoothly transferred from the separation unit to the lower end of the conveyance path member.

According to an aspect of the present invention, the feeding cassette may include an engagement claw on a lower surface of the front end portion. When the feeder cassette is fully pushed into the main body of the image recording apparatus, the engaging claws are engaged with engaging portions provided in the main body. A cam member may be provided between one lower surface side of the feeder box bottom plate and the main body. When the feeder cassette is drawn out from the main body, the cam member guides and raises the feeder cassette, thereby assisting the disengagement of the engagement claw from the engagement portion.

According to this structure, when the feed cassette is pushed into the main body of the image recording apparatus, the cam member lifts the feed cassette. In this state, the engaging claw is also pushed in while the engaging claw is in slight sliding contact with the upper surface of the engaging portion. Pushing in of the feed cassette is also completed almost at the same time when the engaging claws can be engaged with the engaging portions. Therefore, the feeder cassette descends in an almost horizontal state, so that the set state of the feeder cassette relative to the main body can be maintained.

When the feeder cassette is withdrawn, the cam member lifts the leading edge of the feeder cassette an appropriate distance. Therefore, at this time, the engaging claw is in slight sliding contact with the upper surface of the engaging portion. Therefore, disengagement of the engagement claw from the engagement portion can be facilitated. In addition, it is possible to reduce the deformation, abrasion or whitening of the resin, which may be caused by the severe collision of the lower edge of the engagement claw with the engagement portion due to the repeated advance and retraction (attachment or disengagement) operation of the feeder cassette. white. In addition, it is also possible to provide the user with a click sound feeling when the feed box is pushed in or out.

According to an aspect of the present invention, the delivery channel member can be detachably mounted to the main body of the image recording apparatus.

Description of drawings

1 is a perspective view of an image recording apparatus according to an embodiment of the present invention, including an ink jet type recording head;

Fig. 2 is a side sectional view of the image recording device;

3 is a perspective view showing a state in which the main body cover of the image recording apparatus and the cover member of the image reading device are removed;

FIG. 4 is a perspective view of the image recording apparatus, with the image reading device removed in the state shown;

Fig. 5 is an enlarged side sectional view along line IV-IV in Fig. 3;

Fig. 6 is an enlarged side sectional view along line VI-VI in Fig. 4;

Fig. 7 is a perspective view of a paper feeding cassette and a feeding unit;

The perspective view of Figure 8 only shows the paper feeder;

Figure 9 is a plan view of the paper feeding box;

The perspective view of Fig. 10 shows the state that the conveying channel member as U-shaped turning channel is placed on the front end of the paper feeding box;

Fig. 11 is an enlarged sectional view along line XI-XI in Fig. 9;

Fig. 12 is an enlarged side sectional view for explaining operation;

Fig. 13 is a sectional view along line XIII-XIII in Fig. 12;

14 is a perspective view showing the inner surface (surface) of the delivery channel member as a U-shaped turning channel when viewed from the underside;

Figure 15 is a perspective view showing the outer surface of the delivery channel member;

Figure 16 is an enlarged side cross-sectional view along line XVI-XVI in Figures 14 and 15;

Figure 17A is a cross-sectional view along line XVIIa-XVIIa in Figure 10, and Figure 17B is a cross-sectional view along line XVIIb-XVIIb in Figure 10;

Fig. 18 is a sectional view along line XVIII-XVIII in Fig. 10;

Fig. 19 is a partial side view showing a state in which the inclined separation plate is removed from the front end portion of the paper feeding cassette;

Fig. 20 is a cross-sectional view along line XX-XX in Fig. 14, wherein some parts are omitted;

Figure 21 is a perspective view showing the engaging member and the cam member at the lower surface of the paper feeding cassette;

Figure 22 is a perspective view showing a part of the reinforcing bar on the bottom of the opening of the receiving portion of the paper feeding cassette;

Figure 23 is a side view illustrating the transition of the paper feeder cassette from the engaged state to the withdrawn state.

Detailed ways

Embodiments of the present invention are described below.

The image recording apparatus 1 of this embodiment is a multifunction device (MFD) having a printing function, a copying function, a scanning function and a facsimile function, to which the present invention is applied. As shown in FIGS. 1 and 2, a case 2 serving as a main body of an image recording apparatus 1 made of synthetic resin is formed of injection molding made of synthetic resin, and a paper feed cassette 3 is placed on the bottom of the case 2 . The sheet feeding cassette 3 can be inserted through an opening portion 2 a formed on the front side (left side in FIG. 2 ) of the image recording apparatus 1 .

The image reading device 12 is placed on the upper part of the casing 2, and is used for reading documents in copying function and facsimile function. The bottom wall 11 of the image reading device 12 is stacked on the upper cover 30 from the upper cover 30 , and there is basically no gap between the bottom wall 11 and the upper cover 30 . The image reading device 12 is capable of being opened and closed by pivoting up and down around one end of the housing 2 by an unillustrated pivot portion. In addition, the document cover 13 covers the upper surface of the image reading device 12 , and the rear end of the document cover 13 is installed so as to be able to rotate up and down relative to the rear end of the image reading device 12 about a pivot 12 a.

On the upper side of the casing 2 , an operation panel 14 having various operation buttons, a liquid crystal display, and the like is placed in front of the image reading device 12 . The upper surface of the image reading device 12 is provided with a glass plate 16 on which a document can be placed after the document cover 13 is opened upward. An image scanner (CIS: Contact Image Sensor) 17 for reading documents is provided under the glass plate 16 so as to be able to scan along a direction (main scanning direction, Or the guide shaft 44 extending on the Y-axis direction in FIGS. 1, 3 and 4) reciprocates.

The recording unit 7, the paper discharge unit 10, and the ink storage unit 15 provided on the side of the paper discharge unit 10 are arranged below the image reading device 12 and the operation panel 14 so that they are located between the image reading device 12 and the operation panel 14 in plan view. within a projected area of .

2 to 6, the box-shaped main frame 21 and a pair of left and right side plates support the recording unit 7, and the recording unit 7 is formed between first and second guides 22 and 23 having An elongated plate shape and extending in the Y-axis direction (main scanning direction). The recording head 4 of the recording unit 7 is mounted on the carriage 5, and the carriage 5 is slidably supported (mounted) so that the carriage 5 straddles the first guide 22 on the upstream side in the paper conveying direction and the first guide 22 on the downstream side in the paper conveying direction. Two guides 23, so that the carriage 5 can reciprocate between them.

In order to reciprocate the carriage 5, a timing belt 24 is placed on the upper surface of the second guide 23 located on the downstream side in the paper conveying direction (direction indicated by arrow A) so that the timing belt 24 moves in the main scanning direction (Y direction). Axis direction) extends upwards. A timing belt 24 is wound on the pulleys. A CR (Carriage) motor 25 for driving the timing belt 24 is fixed on the lower surface of the second guide 23 . In this embodiment the motor may be any other motor, such as a DC motor or a stepper motor. The second guide 23 is provided with an encoder belt 47 extending in the main scanning direction for detecting the position of the carriage 5 in the Y-axis direction (main scanning direction). The tape-shaped encoder tape 47 is placed such that the detection surface of the encoder tape 47 on which slits are provided at intervals in the Y-axis direction extends in the vertical direction.

A platen plate 26 is fixed to the upper side of the bottom plate 21b of the main frame 21 between the two guides 22 and 23, the platen plate 26 extends in the Y-axis direction so as to face the lower surface of the recording head 4 in the carriage 5 .

A partition plate (lower cover) 29 made of synthetic resin is integrally formed with the casing 2 so that it covers from the lower surface of the guide 23 at the downstream side in the paper conveyance direction to the paper discharge port 10a at the front end of the casing 2 On the upper side of the paper discharge unit 10 (see FIGS. 2 and 4 ), the partition plate 29 is almost at the same height position as the bottom plate 21b of the main frame 21 .

In addition, the upper cover 30 is placed on the partition plate (lower cover) 29, and there is a suitable space between the upper cover 30 and the partition 29, so that the upper cover 30 covers the carriage 5 and its reciprocating passage. on the upper side. In addition, a rectangular window hole 31 (see FIG. 3 ) is formed in the middle part of the upper cover member 30 so that the reciprocating passage of the carriage 5 can be seen from the top. In a case where the paper P causes a paper jam in the recording unit 7 , the user can turn the image reading device 12 by the housing 2 to remove the paper P through the window hole 31 .

The arrangement of the flexible ink supply tubes 20 which always connect the respective ink cartridges 19 accommodated in the ink storage unit 15 and the recording heads 4 in the recording unit 7 will be described below.

The ink storage unit 15 is open to the upper side of the housing 2 . A substantially rectangular ink cartridge 19 (the respective color ink cartridges are indicated by reference numerals 19a-19d; namely black (BK), cyan (C), magenta (M) and yellow (Y) ink cartridges; see FIGS. 3 and 4 ) Containing inks of four colors respectively for full-color recording, the ink cartridge 19 has a small area in plan view and a large height dimension. The ink storage unit 15 is structured such that it can accommodate ink cartridges 19 which are lined up in the X-axis direction and which can be removed from above.

In addition, from each ink cartridge 19 (indicated by reference numerals 19a-19d, respectively) via a plurality (four in this embodiment) of ink supply tubes (ink tubes) 20 (indicated by reference numerals 20a-20d, respectively; see FIG. 5 ) Ink is supplied to the ink jet type recording head 4 . In addition, when ink colors of more than four colors (6 to 8 colors, etc.) are used, ink cartridges corresponding to the number of ink colors can be accommodated in the ink storage unit 15, and the number of ink supply tubes 20 can also be increased according to the number of ink cartridges. .

In this embodiment, the respective ink supply tubes 20a-20d are separate tubes from each other. Also, the ink supply tubes 20a-20d are used with equal lengths.

As shown in FIGS. 4 and 5 , the roots of a plurality (four in this embodiment) of the ink supply tubes 20 are bundled together by a part of one end 15 a of the ink storage unit 15 , and the ink supply tubes 20 are aligned along the Y axis. The direction extends on the upper surface of the lower cover member 29 from one end thereof (right end viewed from the downstream side in the paper conveying direction in FIG. 4 ) to the other end (left end viewed from the downstream side in the paper conveying direction in FIG. 4 ). In this case, the roots of all the ink supply tubes 20 a - 20 d are arranged in a row in the lateral direction along the upper surface of the substantially flat lower cover member 29 . At least part (such as the middle part, etc.) of the ink supply tube 20 is supported by the upper surface of the lower cover member 29 .

Then, all the ink supply tubes 20a-20d are twisted so that the middle portions of the ink supply tubes extend along a longitudinal surface (almost vertical plane) of a laterally longer longitudinal partition plate 32 in the lower cover 29. In addition, the middle portions of all the ink supply pipes 20a-20d are longitudinally arranged in a line and fixed (held or clamped) between one longitudinal surface of the longitudinal partition plate 32 and the longitudinal plate-shaped fixing member 33, the fixing member 33 is used for Made of synthetic resin and fixed with screws or the like so as to be opposed to the one longitudinal surface of the longitudinal partition plate 32 . The fixing member 33 and the portion of one longitudinal surface of the longitudinal partition plate 32 which fix (hold) all the ink supply tubes 20a-20d serve as an intermediate fixing portion.

The carriage 5 is provided with one link extending toward the downstream side in the sheet conveyance direction (direction shown by arrow A) in the substantially horizontal direction. The front ends of all the ink supply tubes 20a-20d are arranged in a substantially horizontal row, and they are connected to a connecting portion of the connecting member provided at the left end as viewed from the downstream side in the sheet conveying direction in FIG. 4 . Between the middle fixing part (fixing piece 33 ) and the connecting part, the orientation of the middle parts of all the ink supply tubes 20a-20d is also changed from left to right. The row (arrangement) phases of all ink supply tubes 20a-20d are twisted and arranged so that the row (arrangement) phases of all ink supply tubes 20a-20d are changed from the substantially vertical direction on the fixing member 33 side to the substantially horizontal direction on the connecting portion side. Thus, although the individual ink supply tubes 20a-20d are bent independently of each other, it is easy to bundle all the ink supply tubes 20a-20d together. Of course all the ink supply tubes 20a-20d are independently separated from each other between the fixing member 33 (intermediate fixing portion) and the connecting portion.

On the outer side of the width of the paper P being conveyed (shorter side of the paper P), at one end (in this embodiment, the right end when viewed from the downstream side in the paper conveying direction in FIG. 4 ), the ink receiving portion is placed, and At the other end (the left end viewed from the downstream side in the paper conveying direction in FIG. 4 ), a maintenance unit is provided. The ink receiving portion and the maintenance unit are not shown in the figure. This configuration enables the recording head 4 to periodically eject ink at the flushing position provided in the ink receiving portion during the recording operation to avoid ink clogging of the nozzles. The ink receiving portion receives thus ejected ink. The maintenance unit is located in the waiting position, facing the carriage 5 . The cap portion of the maintenance unit covers the nozzle surface of the recording head 4 from below, and performs a recovery operation to selectively suck ink of each color or remove air bubbles in an ink damper tank (not shown) of the recording head 4 . In addition, when the carriage 5 moves sideways to approach the maintenance unit, an unillustrated cleaning member (wiping sheet) wipes the nozzle surface for cleaning.

In this embodiment, a flexible flat cable 40 is provided to transmit an instruction signal from an unillustrated control section provided in the casing 2, the instruction signal causes ink to be selectively drawn from the recording head 4 mounted on the carriage 5. Spray from the nozzle. The flexible flat cable 40 is placed so that it is located in the area (movable area, unbound area or unconstrained area) through which the ink supply tubes 20a-20d pass when the carriage 5 reciprocates in the Y-axis direction (main scanning direction), And the flexible flat cable 40 is substantially parallel to the direction in which the ink supply tube extends (see FIG. 4 ).

In addition, the convex bending direction of the curved middle portion of the ink supply tube 20 is set so that its bending direction and the bending direction of the curved middle portion of the flexible flat cable 40 are opposed to each other with respect to the direction in which the carriage 5 reciprocates. This configuration enables the ink supply tube 20 and the flexible flat cable 40 to be arranged at almost the same height in the vertical direction (in almost the same horizontal plane). This enables the entire image recording apparatus 1 to be reduced in thickness.

In addition, a pair of registration rollers (conveying rollers) 27 are placed on the upstream side of the platen 26 for feeding the paper P to a position below the recording head 4 . A bearing (mounting portion) (not shown) for the drive shaft 50 of the paper feed arm 6a and a discharge roller 28 for conveying the paper P to the discharge unit 10 are placed on the downstream side of the platen 26 (see FIG. 2 , 5, and 6), wherein recording is performed on paper P.

The construction of the paper feeding device will be described in detail below. In this embodiment, the sheet feeding cassette 3 is configured to accommodate a plurality of stacked sheets P used as recording media and cut into, for example, A4 size, letter size, a size suitable for writing legal documents, or other sizes, and to make the sheets The shorter side of P extends in a direction perpendicular to the paper conveyance direction (sub-scanning direction and X-axis direction) (direction perpendicular to paper showing FIG. 2 , main scanning direction and Y-axis direction). In addition, the auxiliary support 3a supports the rear end of longer paper P such as paper suitable for writing legal documents, and the auxiliary support 3a is installed at the front end of the paper feeding cassette 3 (corresponding to the front surface of the casing 2) so that it can be moved along the Move in the X-axis direction (see Figures 7 to 10). In the state shown in FIG. 2 , the auxiliary support 3 a is placed at a position such that it protrudes outward from the casing 2 . When the used paper P of, for example, A4 size can be accommodated in the paper feeding cassette 3 (that is, the paper P does not protrude outside the casing 2 through the opening portion 2a), the auxiliary support member 3a can be accommodated in the accommodating portion 3b, thereby assisting The support 3a does not interfere with paper feeding.

The structure of the feeding unit 6 is described below. A drive shaft 50 made of synthetic resin as shown in FIG. 7 is rotatably supported by shaft holes formed on side plates of the main frame 21 and a pair of shaft support plates (both not shown) respectively. . The front end of the drive shaft 50 is inserted into the base portion of the paper feeding arm 6a of the feeding unit 6 so as to protrude therefrom in the lateral direction. In addition, as the drive shaft 50 is rotationally driven, the feed roller 6b is rotated in a predetermined direction (counterclockwise in FIG. 6) by a gear transmission mechanism 6c provided in the feed arm 6a. In addition, a biasing member (such as a torsion spring) (not shown) biases the feed roller 6b so that it is always positioned lower than the bottom plate 21b.

In addition, at the rear end (right side among Figs. 2, 7 and 10, left among Figs. 8 and 9) of the paper feeding cassette 3, an inclined separation plate 8 for separating paper is placed, and the inclined separation plate 8 will be described in detail below. describe. In addition, the base portion of the paper feed arm 6a of the feed unit 6 is mounted on the bottom plate 21b of the main frame 21 in a manner capable of turning in the up and down direction. On the inner surface (surface) of the inclined separation plate 8, an elastic separation pad 8a (composed of a leaf spring in this embodiment) as a separation member is provided at the center portion along the width direction (Y direction), and is provided on the paper feeding arm. The paper feed roller 6b at the lower end of 6a and the elastic separation pad 8a separate and convey the paper sheets P stacked in the paper feed cassette 3 as recording media one by one. The separated paper P is fed to the recording unit 7 through the conveying path member 9, which is arranged in the upper part (in a higher position) compared with the paper feeding cassette 3, and the conveying path member 9 serves as a U-shaped turning path pointing upward to the side (Paper conveying path), the structure of the conveying path member 9 is as follows.

A paper discharge unit 10 is placed above the paper feed cassette 3, and the paper P that has been recorded in the recording unit 7 is discharged onto the paper discharge unit 10 with the recording surface of the paper P facing upward. A paper discharge port 10 a communicating with the paper discharge unit 10 is open together with a front opening portion 2 a of the housing 2 .

In addition, in a state where the auxiliary support 3a of the paper feeding cassette 3 is accommodated in the housing portion 3b, the length of the paper feeding cassette 3 in the X-axis direction is approximately equal to the length of the image reading device 12 plus the operation panel 14 in the X-axis direction. length. Therefore, since the image recording apparatus 1 becomes a cuboid having a substantially square shape in plan view, it is easy to pack the image recording apparatus 1 when it is packed for shipment as a product, and it is also possible to reduce the size of the packaging box.

When the paper feed roller 6b feeds a plurality of sheets (100 sheets in this embodiment) stacked horizontally on the bottom plate 3c of the paper feed cassette 3 made of synthetic resin in the direction toward the conveyance passage member 9 which is a U-shaped turning passage. When P, the double-feed preventing member 51 holds the paper P to be fed last in the paper feeding cassette 3 . The overlapping feed preventing member 51 includes a base pad 52 made of, for example, cork or the like, serving as a high friction coefficient member, and a base plate 53, serving as a low friction coefficient member. The base pad 52 is placed in the bottom plate 3c of the paper feed cassette 3, opposite to the paper feed roller 6b. The base plate 53 is made of a metal plate such as stainless steel.

In this embodiment, the base pad 52 and the base plate 53 are arranged in parallel to each other in a direction perpendicular to the feeding (conveying) direction of the paper P (shown by an arrow in FIG. 12 ). Preferably the base plate 53 is placed on both sides of a single base pad 52 so as to be close to the downstream end of the jumping platform 54 in the conveying direction (see Figures 8, 9, 12 and 13). A jumping platform 54 is integrally formed with and protrudes from the bottom plate 3c, and the jumping platform 54 is higher on the downstream side in the feeding direction. These two base plates 53 are fixed to the upper surface of the base plate 3c with an adhesive. A through hole 55 is formed in the up and down direction on the bottom plate 3c between the positions where the pair of base plates 53 are arranged. A base spring 56 is placed in this through hole 55 , and the base spring 56 functions as a support member, fixed on its upper surface with an adhesive and supports the base pad 52 .

The cylindrical outermost peripheral member 6b1 of the feed roller 6b is made of synthetic rubber or the like. The material and surface shape (that is, the coefficient of friction) of the outermost peripheral member 6b1 are determined so that when the paper feed roller 6b is pressed into contact with the paper P, the frictional force generated between the paper feed roller 6b and the paper P in contact with the paper feed roller 6b is greater than Frictional force generated between a sheet P in contact with the feed roller 6b and another sheet P directly below the sheet P. In this embodiment, elastomer or ethylene-propylene-diene rubber (EPDM) is used as the material constituting the outermost peripheral member 6b1. Knurling is formed on the surface of the outermost peripheral member 6b1 in a direction perpendicular to the conveying direction.

Similarly, the material and surface shape of the base pad 52 are determined such that when the paper feed roller 6b is pressed into contact with the paper P while rotating, the frictional force generated between the base pad 52 and the paper P in contact with the base pad 52 is greater than Frictional force generated between a sheet P in contact with the base pad 52 and another sheet P directly above the sheet P. In this embodiment, cork is used as a material constituting the base pad 52 .

In addition, the material and surface shape of the base plate 53 are determined such that when the paper feed roller 6b is pressed into contact with the last sheet P while rotating, a gap is generated between the paper feed roller 6b and the paper P in contact with the paper feed roller 6b. The frictional force is greater than that generated between (a) the base pad 52 and the base plate 53 and (b) the paper P in contact with the base pad 52 and the base plate 53 . In this embodiment, a stainless steel plate with a small surface roughness is used as the base plate 53 . Alternatively, nickel-plated steel sheets may be used.

In addition, the width W1 (dimension in the direction perpendicular to the feeding direction) of the outermost peripheral piece 6b1 is set so that the outermost peripheral piece 6b1 spans at least the middle portion in the width direction of the base plate 53 on both sides of the base pad 52 (see Figure 13).

The base spring 56 is made of a metal plate spring having elasticity, and the base spring 56 is installed so that the engagement hole 56a is engaged with the engagement claw 54a so as not to fall off therefrom, the engagement hole 56a is formed in the base portion of the base spring, and the engagement claw 54a is engaged with the jump platform 54. The lower surface is integrally formed. In addition, near the engagement hole 56a of the base portion of the base spring 56, a positioning hole 56b, such as a circular hole, is formed, and the positioning hole 56b closely engages with the protrusion 54b protruding from the lower surface of the jump platform 54, so that the extension of the base spring 56 The outgoing direction is not offset in the left-right direction. The base spring 56 is thus supported by the bottom plate 3 c in a cantilever manner, and the front end (free end) of the base spring 56 is elastically biased toward the upper side of the through hole 55 .

The front end (free end on the downstream side in the sheet feeding direction) of the base spring 56 includes a regulator 57 for preventing floating, which is bent so as to have a U-shaped section. With this structure, in the state where the outermost peripheral member 6b1 of the paper feed roller 6b does not press down on the base pad 52 (including the state in which the outermost peripheral member 6b1 does not press the base pad 52 with the paper P on the bottom plate 3c; this state is called no load state), the front edge (upper edge) of the adjusting member 57 is abutted against the lower surface of the bottom plate 3c near the through hole 55 to adjust the base pad 52, so that in the surface (upper surface) of the base pad 52 on the base spring 56 , a portion of the surface located at a position corresponding to the portion in contact with the paper feed roller 6b protrudes upward from the surface (upper surface) of the base plate 53 to an extent that does not exceed a predetermined value (about 0.5 mm in this embodiment), and the base The height of the surface (upper surface) of the plate 53 is fixed at the corresponding position. In addition, the predetermined value varies depending on the thickness, material, or shape in plan view of the base spring 56 . The predetermined value may be designed so that the base pad 52 does not become as high as the base plate 53 due to the pressing contact force of the feed roller 6b when the penultimate sheet P is fed. In addition, the height position of the surface of the base pad 52 on the upstream side in the feeding direction is set to be almost the same as the height position of the surface (upper surface) of the base plate 53 at the corresponding position. In addition, the surface of the base pad 52 is set such that when the feed roller 6b pushes the base pad 52 in, the base pad 52 and the base plate 53 are substantially parallel to each other so that the base pad 52 and the base plate 53 have the same height.

In this embodiment, the base spring 56 is formed in a substantially trapezoidal shape in which the width at the base end thereof is greater than the width at the free end thereof when viewed from a plan view. When viewed in plan view, the base plate 53 is formed in a substantially trapezoidal shape whose width on the upstream side in the sheet feeding direction is smaller than on the downstream side in contrast to the base spring 56 (see FIGS. 8 and 9 ).

In this way, when the base plate 53 is placed on the left and right sides of the base spring 56, the required dimension of the base plate 53 in the width direction can be shortened as much as possible. In addition, the curved cross-sectional area of the base spring 56 may be increased. This relieves any stress concentrations.

When the base plate 53 as a low friction coefficient member is made of a plate material including metal such as stainless steel, its abrasion resistance is high and its surface friction coefficient is low. Therefore, compared with the case where the surface of the bottom plate 3 c made of synthetic resin is used as a low-friction coefficient member, the feeding operation for the last sheet P can be reliably performed. In addition, on the surface of the bottom plate 3c, between the base pad 52 and the base portion of the inclined separation plate 8, an upward guide portion 3e having an inclined surface is integrally formed on the upstream side in the feeding direction of the paper P. low and becomes high toward the downstream side of the feed direction (see Figures 9 and 12). According to this structure, when the number of sheets P stacked in the sheet feeding cassette 3 decreases, the leading end of the sheets P fed by the sheet feeding roller 6b abuts against the lower portion of the inclined separation plate 8 that is higher than the base portion of the inclined separation plate 8 . In this way, the upward feeding operation of the paper P can be performed smoothly. In addition, the upward guide portion 3 e may include a flat portion at a higher portion of the guide portion substantially parallel to the surface of the bottom plate 3 c and extending toward the base portion of the inclined separation plate 8 .

In addition, in the direction perpendicular to the feeding direction of the paper P (Y direction; the width direction of the paper P), the surface of the inclined separation plate 8 is formed as a convex curved surface (see FIG. 9 ), which ( a) protruding toward the leading edge of the paper P at a portion near the sawtooth-shaped separation pad 8a serving as a separator on the central portion of the paper P in the width direction on the central portion in the width direction of the paper P; and (b ) retracts from the leading edge of the paper P as approaching both end portions of the paper P in the paper P width direction. Thus, the surface of the inclined separation plate 8 is a convex curved surface so that the leading edge of the paper P being fed is on the widthwise center portion thereof immediately before both end portions in the width direction of the paper P abut against the inclined separation plate 8 Sliding contact with the separation pad 8a for separating the paper P is ensured.

In addition, near the upper end of the inclined separation plate 8, freely rotatable rollers 60 for smoothly guiding the paper P in the direction toward the conveyance path member 9 are installed on the left and right sides of the separation pad 8a (see FIGS. 8, 9 and 18). In addition, the inclined separating plate 8 and the paper feeding cassette 3 are separately formed so that the inclined separating plate 8 is detachably mounted on the front end of the paper feeding cassette 3 (see FIG. 19 ).

The structure in which the paper feeding arm 6a automatically moves up or down when the paper feeding cassette 3 is inserted into or drawn out from the bottom of the casing 2 will be described below. A substantially plate-shaped cam follower 58 is disposed on the lower surface side of the bottom plate 21b of the main frame 21 parallel to the drive shaft 50 and integrally projected from the paper feed arm 6a made of synthetic resin. In the sheet feeding cassette 3, the cam follower 58 extends to a cam portion 59 on the upper surface of the side plate 3d (see FIG. 7). In addition, the cam follower 58 is provided so that most of the paper feed arm 6a and paper feed roller 6b rotated and raised are accommodated on the upper surface side of the main frame 21 through the opening 21c (see FIG. 6 ) of the bottom plate 21b. Next, the cam follower 58 is generally close to the lower surface of the bottom plate 21b so as to be substantially parallel thereto.

Cam portions 59 are integrally formed on the upper end surfaces of the opposite left and right side plates 3d, which are two opposite end portions in the Y-axis direction, which hold the paper P accommodating portion in the paper feeder cassette 3 made of synthetic resin. The bottom plate 3c is sandwiched in the middle (see FIGS. 7 to 9), and the cam portion 59 is in sliding contact with the cam follower 58 as the paper feeder cassette 3 advances or retracts (movement in the X-axis direction), thereby integrally upward Or move the feed arm 6a and feed roller 6b downward.

According to this structure, when the paper feeding cassette 3 is inserted through the opening portion 2a at the front of the housing 2, then the lower surface of the cam follower 58 and the starting end of the cam portion 59 (the side near the inclined separating plate 8 as the inclined member) Closely abutting, as the paper feeding cassette 3 moves forward, the cam follower 58 is pushed up, and the paper feeding arm 6a and the paper feeding roller 6b rotate upwards along with the cam follower 58 as a whole. Then, the feed arm 6 a and the feed roller 6 b go over the upper side of the inclined separation plate 8 . In a state where the feed arm 6a and the feed roller 6b are raised, the feed arm 6a and the feed roller 6b are accommodated in the upper space of the bottom plate 21b (in the main frame 21) through the opening 21c. At this time, the flat cam follower 58 is also in abutment or close contact with the lower surface of the bottom plate 21b. Therefore, without increasing the vertical space height between the bottom plate 21b of the main frame 21 and the paper feeding cassette 3, the vertical rotation operation of the paper feeding arm 6a and the paper feeding roller 6b can be ensured. In other words, since the height from the sheet feeding cassette 3 to the bottom plate 21b of the main frame 21 can be reduced, it is possible to provide a compact image recording apparatus 1 whose overall height is reduced.

When the cam follower 58 is in the descending portion after passing the uppermost position of the cam portion 59, the feed arm 6a and the feed roller 6b are biased downward to rotate downward. Then, the paper feed roller 6b can be brought into abutment with the uppermost one of the paper sheets P stacked in the accommodating portion 3b.

When the paper feeding cassette 3 advances to the innermost position in the casing 2 (set state), if one end (lower end) of the cam follower 58 of the paper feeding arm 6a abuts against the lowest position of the cam portion 59, the paper feeding The roller 6b can abut against the double feed preventing member 51 (see FIGS. 7 and 12).

In this way, since the feeding unit 6 is provided with the cam follower 58 positioned lower than the bottom plate 21b of the main frame 21, and the paper feeder cassette 3 is provided with the cam portion 59, as the paper feeder cassette 3 is provided with respect to the inside of the housing 2 (main body housing), The forward or retracted movement of the cam portion 59 at least temporarily raises or rotates the feeding unit 6 and the cam follower 58, so that the feeding unit 6 can be automatically raised and lowered as the paper feeding cassette 3 is advanced and retracted, so that the Operation becomes simple.

The conveyance passage member 9 as a U-shaped turning passage (transport passage member) is manufactured by injection molding synthetic resin, and the conveyance passage member 9 conveys the paper P from the upper end of the inclined separation plate 8 to the recording unit 7, and the conveyance passage member 9 is manufactured so that It has a transverse U-shaped plate portion 9 a in side view. On the back (rear side) of the left and right sides of the transport passage member 9, elastic engaging portions 62 and elastic adjuster portions 63 are formed integrally with the plate portion 9a (see FIG. 15). At the upper end of the inclined separation plate 8 of the paper feeding cassette 3 pushed into the bottom of the housing 2 , the conveying passage member 9 can be inserted into the inside of the housing 2 through an opening defined at the rear end of the housing 2 . The delivery channel member 9 can be attached to and detached from the housing 2 in a predetermined posture. Therefore, when a paper jam occurs, it is easy to detach the conveying path member 9 from the housing 2, so that it is easy to deal with the paper jam.

As shown in FIGS. 6, 10, and 14 to 18, a plurality of ribs 61 are integrally protruded from the plate portion 9a at appropriate intervals in the width direction (Y direction) perpendicular to the conveyance direction, and these ribs 61 are parallel to the sheet P. The conveying direction extends. In this case, the cross-sectional shape of each rib 61 is laterally symmetrical about the center of the sheet P in the width direction. Each rib 61 has a gentle slope 61a directed outward in the width direction of the sheet P at an obtuse angle θ1 (see FIG. 20 ). The obtuse angle θ1 is an angle defined between the surface of the plate portion 9a and the gentle slope 61a, and preferably ranges from 130 degrees to 140 degrees. According to this structure, when the paper P whose width is approximately equal to the distance between the pair of right and left ribs 61 and left ribs 61 is conveyed, even if the conveyance position of the paper P is slightly deviated in the paper P width direction, the paper P can be placed along the The side edge of the conveying direction is such that the side edge forms an obtuse angle θ1 with the slope 61a and the sliding resistance is small. Therefore, it is possible to prevent the problems occurring in the prior art, such as in the prior art including the ribs standing upright from the surface of the plate portion, the side edges of the conveyed paper P hitting the upright sides of the ribs and being affected. It is constrained so that the curved running of the paper P causes paper jams, or undulating streaks (referred to as wrinkles) extending in the conveying direction are generated on the surface of the paper P.

As shown in FIG. 14, similarly to the inclined separating plate 8, on the upstream side in the sheet conveying direction, the envelope line respectively connecting the inner surface of the plate portion 9a of the conveying path member 9 and the front ends of the plurality of ribs 61 is formed as a convex one. A curved surface that protrudes at the central portion of the conveying channel member 9 in the width direction and gradually retracts as approaching the end portion of the conveying channel member 9 in the width direction. Therefore, the front edge of the paper P conveyed along the inner surface (surface) of the conveyance path member 9 hardly touches the inner surface (surface) of the plate portion 9a on the left and right sides in the width direction, so that conveyance resistance can be reduced.

A plurality of freely rotatable rollers 64 are provided at least in the central portion of the transport path member 9 in the width direction of the sheet P (see FIGS. 14, 16 and 17B). The plurality of rollers 64 are arranged at appropriate intervals along the conveyance direction of the sheet P. As shown in FIG. Subscripts a, b, c, and d are given to the respective rollers 64 in order from the upstream side. In addition, the diameter of the roller 64 placed on the upstream side in the conveying direction is larger than the diameter of the other roller 64 placed on the downstream side.

In this embodiment, the most downstream roller 64c and the upstream roller 64d adjacent thereto have almost the same diameter. In addition, in this embodiment, two rollers 64 having the same diameter are provided at appropriate intervals in the width direction of the sheet P. As shown in FIG.

The plate portion 9a of the conveyance path member 9 is integrally formed with an accommodating portion 66 that exposes the respective rollers 64a to 64d and their support shafts 65 to the surface through which the paper P passes (see FIGS. 14, 15, 16 and 17A). The support portion 67 is used to support those support shafts 65 protruding from both ends of the respective rollers 64a to 64d, and the support portion 67 is recessedly formed in the accommodation portion 66 as an open recess having a substantially semicircular arc-shaped cross section. groove.

A cover 68 made of synthetic resin is detachably placed on the surface of the accommodating portion 66, thereby exposing at least a part of the outer peripheral surface of each roller 64a to 64d and covering the supporting portion 67 of each supporting shaft 65 (see FIG. 14 , 16 and 17A). In addition, the cover member 68 is curved in a lateral U-shape in side view so as to extend along the surface of the plate portion 9a. In the wider surface of the cover member 68, window holes 68a are formed at predetermined corresponding positions, and the window holes 68a allow a part of the outer peripheral surface of each of the rollers 64a to 64d to be exposed. The lower portion of the cover 68 defines a recess 70 which engages with a protrusion 69 protruding from the plate portion 9a. In addition, the upper end of the cover member 68 is formed with engaging claws 72 that engage with stepped engaging portions 71 formed at the upper end of the plate portion 9a (see FIG. 16 ). With this structure, the structure of the supporting portion 67 of the rollers 64a to 64d can be made simple, and the assembly and replacement work of the respective rollers 64a to 64d can be facilitated.

As described above, the diameter of the roller 64a on the upstream side in the conveying direction is larger, and the height at which the outer peripheral surface of the roller 64a protrudes from the cover member 68 is smaller, so that the angle between the surface of the cover member 68 and the outer peripheral surface of the roller 64a is an obtuse angle close to 180 degrees. This makes it possible to greatly reduce the resistance caused when the leading edge of the paper P moving upward from the inclined separation plate 8 comes into contact with the outer peripheral surface of the roller 64a. Therefore, the operation of conveying the paper P to the downstream side of the plate portion 9a bent in a U shape can be smoothly performed, thereby effectively preventing occurrence of paper jams.

In addition, as for the rollers 64a to 64d, the diameter of each roller continuously increases from their end portions toward their center portions. Preferably, the largest diameter portion of the rotating outer peripheral surface of the roller is formed as a cylindrical surface, or the entire rotating outer peripheral surface of the roller is formed as a convex curved surface. Therefore, no streaks are formed on the recording surface (facing the front surface of the plate portion 9 a ) of the conveyed paper P, and the image recording quality subsequently performed in the recording unit 7 is not impaired. In addition, if the intersection between the rotating outer peripheral surface of each roller 64a to 64d and the end surface of each roller 64a to 64d is removed (the intersection is rounded), it is possible to reliably avoid the Streaks appear on the recording surface, further stabilizing image recording quality.

In this embodiment, for normal paper, the maximum stacked amount of paper P in the paper feeder cassette 3 is set to about 100 sheets, and the stack height ( H1 ) is set to about 10 mm. Corresponding to this, the height of the inclined separating plate 8 (the vertical height from the upper surface of the bottom plate 3c to the upper end of the inclined separating plate 8) is increased so that the paper P can be smoothly transferred to the plate of the conveying path member 9 at the time of maximum stacking. The lower end of part 9a. Preferably, the upper edge 8b of the inclined separation plate 8 extends to a position higher than the lower edge of the plate portion 9a, so that the inclined separation plate 8 covers the front surface side of the plate portion 9a, that is, partially overlaps with the plate portion 9a (see FIGS. 17A and 9a ). 18).

9, 10, 11, 17B, 18 and 19, since the inclined separation plate 8 is formed as a convex curved surface, between the base portion of the inclined separation plate 8 and the rear edge of the bottom plate 3c of the paper feeding cassette 3 A gap is formed therebetween, and in order to close the gap, the base portion of the inclined separation plate 8 is integrally formed with auxiliary ribs 73 having a suitable length and a substantially triangular cross-sectional shape at predetermined intervals in the Y direction. When the sheets P are fed in the vicinity of the bottom plate 3c in a state where the stacked amount of the sheets P is small, the existence of the auxiliary rib 73 allows the leading edge of the sheet P to be reliably guided to the upper side of the inclined separation plate 8, while the leading edge of the sheet P will not fit into this gap.

The structures shown in FIGS. 21 to 23 can maintain the engaged state in which the paper feeding cassette 3 is inserted substantially horizontally through the opening portion 2 a of the lower housing portion of the housing 2 and can easily release the engaged state when the paper feeding cassette 3 is drawn out. Specifically, the lower surface of the sheet feeding cassette 3 made of synthetic resin is integrally formed with reinforcing ribs 76 elongated toward the opening portion 2a in the insertion direction. The reinforcing rib 76 is integrally formed with a cam portion 77 having a substantially trapezoidal shape in a downward view. A plurality of (two in this embodiment) reinforcing ribs 76 and cam portions 77 are provided at appropriate intervals in the Y direction. On the other hand, on the bottom surface of the casing 2 made of synthetic resin, a connecting piece 79 is integrally formed, and the connecting piece 79 connects the paper feeding cassette 3 in a direction (Y direction) perpendicular to the insertion direction (X direction) of the paper feeding cassette 3 . 3.

When the paper feeding cassette 3 is inserted into the casing 2 substantially horizontally, the lower edge of the cam portion 77 is in sliding contact with the upper surface of the coupling member 79 . At the position where the process of inserting the paper feeding cassette 3 into the casing has been completed, the cam portion 77 is located in the inward space of the rear edge 79a of the connecting piece 79, and the lower edge of the cam portion 77 falls into the upper edge of the connecting piece 79. in the space below the surface (see solid line in Fig. 23). Conversely, when the paper feeding cassette 3 is drawn out, the front edge of the cam portion 77 abuts against the rear edge 79a of the connecting member 79 . Then, the cam member is constituted by the cam portion 77 and the connecting piece 79 so that the lower edge of the cam portion 77 moves substantially horizontally to the front side of the housing 2 while straddling the upper surface of the connecting piece 79 (see double in FIG. 23 ). Dotted line).

In addition, a plate-shaped engagement claw 80 and a pair of guide plates 81 located on the left and right sides of the engagement claw 80 protrude downward, and are integrally formed between the front end reinforcement plate 78 of the paper feed cassette 3 and the cam portion 77 of the paper feed cassette 3 (See Figures 21 to 23). The engagement claw 80 is elongated in the Y direction and flat in the X direction. Both guide plates 81 are elongated in the X direction and flat in the Y direction. On the other hand, the front end of the connecting piece 79 is formed with an engaging portion 82 corresponding to the positions of the engaging claw 80 and the pair of guide plates 81 . The engagement portion 82 includes a protrusion 83 and a guide groove (attraction groove) 84, the protrusion 83 keeps the pushed-in state of the engaging pawl 80, the guide groove 84 is provided on the left and right sides of the protrusion 83, they are elongated in the X direction and The front end is open (see Figures 22 and 23).

In the above structure, when the paper feeding cassette 3 is pushed into the casing 2, the lower edge of the cam portion 77 rides on the upper surface of the connecting member 79. As shown in FIG. In this state, while the lower edge of the engagement claw 80 is in slight sliding contact with the upper surface of the protrusion 83 , the lower edge of the engagement claw 80 is also pushed in. When the lower edge of the engagement pawl 80 passed over the rear end of the projection 83, almost at the same time (at the moment when the push-in was completed), the leading edge of the cam portion 77 had moved past the rear edge 79a of the connecting piece 79, and the paper feeding cassette 3 Descending in an almost horizontal state, and the rear end surface of the protrusion 83 blocks the engaging claw 80 , so that the set state of the paper feeding cassette 3 relative to the housing 2 can be maintained.

As mentioned above, when the paper feeding cassette 3 is drawn out, the lower edge of the cam portion 77 rides on the upper surface of the connecting member 79, thereby lifting the front end of the paper feeding cassette 3 by an appropriate distance (see FIG. 23 from the solid line). state transition to double-dot-dash-line state). Therefore, at this time, the lower edge of the engagement pawl 80 is also in slight sliding contact with the upper surface of the protrusion 83 . Therefore, disengagement of the engagement claw 80 from the engagement portion 82 can be facilitated. In addition, it is possible to reduce the deformation, abrasion or whitening of the resin, which may be caused by the severe collision of the lower edge of the engagement claw 80 with the protrusion 83 due to the repeated advance and retraction (attachment or disengagement) operation of the paper feeding cassette 3 , frayed or whitened. In addition, it is also possible to provide the user with a click sound feeling when the paper feeding cassette is pushed in or pulled out.

Claims (13)

1. image recorder comprises:

A main body;

An image recording unit, image recording unit forms image on recording medium;

A transfer passage is fed to image recording unit to recording medium by transfer passage, and image recording unit and transfer passage are placed in the main body;

A feed cassette, it is placed on the bottom of main body and is placed on below the image recording unit, thereby can move forward and backward, and can hold the recording medium that piles up in the feed cassette;

A feed roller, feed roller is fed to transfer passage to the recording medium that is stacked on the feed cassette; With

A separative element, separative element are placed on an end of feed cassette, thereby separate recording medium from the recording medium that piles up, and with the feed roller cooperation recording medium that separates upwards are transported to transfer passage, wherein:

Transfer passage comprises a transfer passage spare, and transfer passage spare has be the board of U-shaped on the side-looking direction;

Transfer passage spare comprises a plurality of rollers, and described a plurality of rollers are located at the central part office of transfer passage spare on the Width vertical with the throughput direction of recording medium in the mode that can freely rotate,

On the throughput direction of recording medium, arrange described a plurality of rollers;

When recording medium was fed to described record cell, described a plurality of rollers always separated with described feed roller; And

The diameter of a roller that is positioned at the throughput direction upstream is greater than the diameter of another roller that is positioned at the throughput direction downstream.

2. image recorder as claimed in claim 1, wherein the diameter of each roller increases to the core of each roller gradually from the end of each roller.

3. image recorder as claimed in claim 1, the bight of wherein removing the intersection between the end surfaces of the outer surface of each roller and each roller.

4. image recorder as claimed in claim 1, wherein:

Transfer passage spare further comprises a holding portion, holds the axle of roller and roller in this holding portion, and this holding portion is exposed to roller and axle outside the surface of recording medium process of transfer passage spare simultaneously; And

Cover piece removably is placed on this surface of recording medium process of transfer passage spare, thereby exposes at least a portion of each roller and cover the axle of roller.

5. as the described image recorder of any one claim in the claim 1 to 3, wherein:

At the upstream side of the throughput direction of recording medium, the surface that the recording medium of transfer passage spare slips over forms the curved surface of projection; And

This protruding curved surface is outstanding in the central part office of transfer passage spare broad ways, and along with near transfer passage spare on Width the end and withdrawal gradually.

6. as the described image recorder of any one claim in the claim 1 to 2, wherein:

Transfer passage spare further comprises a plurality of ribs that stretch out from the surface of recording medium process, and these ribs extend on the throughput direction of recording medium, and is arranged in position than roller more lateral with predetermined interval; And

Each rib has cross-sectional plane on the Width of recording medium, in this cross-sectional plane, each rib becomes the obtuse angle outward-dipping with Width.

7. image recorder as claimed in claim 6, wherein:

At the upstream side of the throughput direction of recording medium, the surface that is slipped over by the recording medium that transfer passage spare and rib limited forms the curved surface of projection; And

This protruding curved surface is outstanding in the central part office of transfer passage spare broad ways, and along with near transfer passage spare on Width the end and withdrawal gradually.

8. as the described image recorder of any one claim in the claim 1 to 4, wherein:

Separative element is included in the separation member of the central part office on the Width, and separation member is near the forward position of recording medium, thereby one connects a ground separation recording medium; And

Separative element further comprises the plate of lobed curved surface, and this protruding curved surface is outstanding to the forward position of recording medium near separation member, and along with near recording medium on Width the end and from the forward position withdrawal of recording medium.

9. image recorder as claimed in claim 8 wherein forms a rib with the base part of separative element is whole, thereby is enclosed in the gap that forms between the base part of separative element of the base plate of feed cassette and lobed curved surface.

10. image recorder as claimed in claim 8, wherein:

A friction member is placed in the face of feed unit by base plate place in feed cassette;

On base plate, place a upwards leader, upwards leader is positioned at the downstream of friction member on the throughput direction of recording medium, and between the base part and friction member of separative element, upwards leader is lower in friction member one side, and uprises gradually towards base part one side.

11. as the described image recorder of any one claim in the claim 1 to 4, wherein:

Separative element comprises an inclination plate; And

On a recording medium receiving surface of transfer passage spare, a upper edge of inclination plate extends to a position higher than the lower edge of transfer passage part, thereby inclination plate and transfer passage spare are partly overlapping.

12. as the described image recorder of any one claim in the claim 1 to 4, wherein:

Feed cassette comprises an engaging claw on the lower surface of fore-end, and when feed cassette was pushed in the main body of image recorder fully, engaging claw engaged with bonding part in being arranged on main body; And

Between lower face side of feed cassette base plate and main body, be provided with cam member, when from main body, extracting feed cassette out, cam member guiding and rising feed cassette, thus help engaging claw and bonding part to unclamp.

13. as the described image recorder of any one claim in the claim 1 to 4, wherein transfer passage spare is releasably attached on the main body of image recorder.

Images