JP2003072959A - Paper feeder, and recording device provided with the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent deformation of a hopper by an energizing means for press- contacting the hopper with a paper feed roller and a hopper release means for separating the hopper from the paper feed roller, and conduct normal paper feeding operation. SOLUTION: The hopper 6 is so provided that a lower part is press-contact with and separates from the paper feed roller 3 by rocking around a rotation shaft provided on an upper part. The press-contact operation of the hopper 6 with the paper feed roller 3 is conducted by a compression coil spring 7 provided on a rear surface side of the hopper 6, and the separation operation of the hopper 6 from the paper feed roller 3 is conducted by a release bar 16 which is provided on the rear surface side of the hopper 6 and is driven to rotate. A point of application of force applied to the hopper 6 from the compression coil spring 7 and a point of application of force applied to the hopper 6 from the release bar 16 are arranged in a same position, and thereby the bending moment is not generated on the hopper and deformation of the hopper 6 can be prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet feeding device for accumulating and holding a plurality of recording materials in an inclined posture and feeding one by one from the uppermost one to the downstream side. The present invention also relates to a recording apparatus including the paper feeding device.

[0002]

2. Description of the Related Art A printer is one of recording devices,
2. Description of the Related Art Some printers include a paper feeding device that feeds printing paper as a recording material to the downstream side one by one. Furthermore,
Such a sheet feeding device includes a sheet feeding roller that is rotationally driven,
The printing paper is a plate-shaped member that is long in the width direction, is provided in an inclined posture when the printing paper feeding path is viewed from the side, and is provided with a rotation fulcrum at the upper portion, and is rotated to rotate relative to the paper feeding roller. There is a hopper that performs a separating operation and a pressure contacting operation, pushes up the printing paper accumulated and held by the hopper, presses the accumulated uppermost one to a paper feed roller, and then performs feeding.

23 and 24 show a sheet feeding device 500 according to such a conventional technique. FIG. 23 is an external perspective view of the sheet feeding device 500, and FIG. FIG. 23 is a cross-sectional view taken along the line xx) and FIG. 24B is an explanatory diagram showing a point of action of an external force applied to the hopper 501. As shown in FIGS. 23 and 24A, the sheet feeding device 500 includes a hopper 501 provided in an inclined posture, and the hopper 501 accumulates and holds a plurality of sheets P. A movable guide 502 is provided in the hopper 501 so as to be slidable in the width direction of the paper P, and guides the side edge of the paper P together with the fixed guide 503. The hopper 501 has a rotating shaft 5 at the top.
01a, and the lower part performs the pressure contact operation and the separation operation with respect to the paper feed rollers 504a and 504b by rotating around the rotation shaft 501a.

The sheet feeding device 500 includes two sheet feeding rollers 504.
a and 504b, the paper feed roller 504a is fixed below the fixed guide 503, and the paper feed roller 504b is provided so as to slide together with the movable guide 502 according to the width of the paper P. The uppermost one of the stacked sheets P is fed one by one by one sheet feeding roller.

[0005]

Here, the hopper 501 is used.
The rotation operation of the sheet feeding roller 504 is performed by sandwiching the hopper 501.
a, 504b and pressing springs 508a and 508b as biasing means, which are respectively arranged at positions facing each other, and the hopper 5.
01 cams (cams 505a and 505b and cam followers 506a and 506b) as hopper release means arranged at the lower ends of both ends. That is, the pressing springs 508a and 508b connect the hopper 501 to the paper feed rollers 504a and 504 from the lower rear surface of the hopper 501.
By pushing up toward b, the hopper 501 rotates in a direction in which it comes into pressure contact with the paper feed rollers 504a and 504b.

The cams 505a and 505b provided on both ends of the paper feed roller shaft 507 push down the cam followers 506a and 506b provided at the lower ends of both ends of the hopper 501, so that the hopper 501 moves the paper feed roller 50.
4a, 504b is rotated in the direction of being separated (released). The pressing springs 508a and 508b are arranged at the positions facing the sheet feeding rollers 504a and 504b, respectively, in order to surely press the hopper 501 to the sheet feeding rollers located opposite to each other. is there.

However, with the pressing springs 508a and 508b,
The points of action of the forces applied to the hopper 501 by the cams 505a and 505b are at different positions on the plane formed by the hopper 501 (the left-right direction in the figure and the front-back direction of the paper) as shown in FIG. From this, it is clear that a bending moment is generated in the hopper 501, and the hopper 501 is temporarily or in a future curved state as shown by an imaginary line. Hopper 50 like this
If 1 is bent by a bending moment, various problems such as a decrease in the maximum number of sheets of the paper P to be set or a skew (skew) when the paper P is fed occur.

Therefore, the present invention has been made in view of the above problems, and its problem is to deform the hopper by the biasing means for pressing the hopper against the paper feed roller and the hopper release means for separating the hopper from the paper feed roller. Is to prevent the paper feed operation and to perform a normal paper feed operation.

[0009]

In order to solve the above-mentioned problems, the paper feeding apparatus according to the first aspect of the present invention has a paper feeding roller for feeding the recording material to the downstream side by rotating, and a recording material. A hopper that is formed of a plate-shaped member that is long in the width direction of the material, has a rotation fulcrum on the upstream side from the pressure contact with the paper feed roller, and performs a separation and pressure contact operation with respect to the paper feed roller by rotating. And a biasing means disposed at a position facing the paper feed roller with the hopper sandwiched therebetween, for biasing the hopper from the rear side of the hopper toward the paper feed roller, and a biasing means against the biasing means. And a hopper releasing means for separating the hopper from the paper feed roller, and stacking and holding a plurality of recording materials in an inclined posture and pushing up the recording materials stacked and held by the hopper. Downstream one by one from the upper recording material In a plan view of the hopper, a sheet feeding device that feeds the hopper, the point of action of the force applied to the hopper by the urging means, and the point of action of the force applied to the hopper by the hopper release means. It is characterized in that they are arranged at substantially the same position.

According to the first aspect of the present invention, the bending moment is hardly generated in the hopper, so that the deformation of the hopper can be prevented and the normal feeding operation can be maintained. That is, the hopper is composed of a plate-shaped member that is long in the width direction of the recording material, and is provided so as to be rotatable around a rotation fulcrum provided on the upper portion. Here, the sheet feeding device includes an urging means for rotating the hopper in a direction of being pressed against the sheet feeding roller and a hopper releasing means for rotating the hopper in a direction of separating from the sheet feeding roller, and these apply a force to the hopper. The hopper is configured to be rotated by causing the hopper to rotate, but in the invention according to claim 1 of the present application, the point of action of the force applied to the hopper by the urging means and the force applied to the hopper by the hopper release means. The point of action and the point of action are arranged at substantially the same position in a plan view of the hopper. Therefore, almost no bending moment is generated in the hopper, which prevents the hopper from curving, thereby maintaining a normal sheet feeding operation.

According to a second aspect of the present invention, there is provided the paper feeding device according to the first aspect.
In the above, one of the paper feed rollers is provided at a position biased to one of the rotary shafts of the paper feed roller.

According to the second aspect of the present invention, since one paper feed roller is provided at a position offset to one of the rotary shaft ends of the paper feed roller, the paper feed roller is provided. Since only one urging means and one hopper release means are sufficient because only one is provided, the cost can be reduced, and the paper feed roller has one of its rotating shafts on either side of its shaft end. Since it is provided at a position deviated from, it is possible to deal with both a recording material having a small widthwise dimension and a recording material having a large widthwise dimension. Even when one or more paper feed rollers are provided, the point of action of the force applied by the urging means to the hopper and the point of action of the force applied by the hopper release means to the hopper are substantially the same position. Needless to say, if it is arranged in the above-mentioned manner, the operation and effect of the invention described in claim 1 of the present application can be obtained.

According to a third aspect of the present invention, there is provided a sheet feeding device according to the first aspect.
Or 2, the hopper release means has a first shaft portion extending in the longitudinal direction of the hopper above the biasing means, and a tip extending vertically from one end of the first shaft portion to the vicinity of the biasing means. A second shaft portion that engages with an engagement portion provided on the back side of the hopper, and a third shaft portion that extends from the other end of the first shaft portion substantially in parallel with the second shaft portion. When,
Consisting of a release bar having a substantially U-shape in a plan view, a bearing portion that supports the first shaft portion, and the third shaft portion, thereby operating the second shaft portion. It is characterized by comprising a release bar rotating means for rotating the first shaft portion in a direction away from the paper feed roller with the first shaft portion as a rotation shaft.

According to the third aspect of the present invention, the hopper release means engages with the rear surface of the hopper, and has a substantially U-shaped release bar in plan view, and a release bar rotating means for rotating the release bar. Since the hopper is rotated in the direction of separating from the sheet feeding roller by rotating the release bar, the space required on the back side of the hopper can be minimized, and the hopper release can be performed with a simple structure. Means can be configured.

According to a fourth aspect of the present invention, there is provided the paper feeding device according to the third aspect.
In the above, the drive source of the release bar rotating means is also used as the drive source of the paper feed roller. According to the fourth aspect of the present invention, the drive source of the release bar rotating means for rotating the release bar is also used as the drive source of the sheet feeding roller, so that the release bar rotating means can be constructed at low cost. Is possible.

A recording apparatus according to a fifth aspect of the present invention comprises a recording section for recording on a recording material, and a discharge section for discharging the recording material recorded by the recording section. In addition, the sheet feeding device according to any one of claims 1 to 4 is provided.

According to the invention of claim 5 of the present application, the recording apparatus includes the paper feeding device of any one of claims 1 to 4, and therefore, any one of the above claims 1 to 4 of the present application. It is possible to obtain the same effect as the invention described in the item 1.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings in the order of "overall configuration of an inkjet printer", "overall configuration of a sheet feeding device", and "configuration of hopper release means". .

<Overall Configuration of Inkjet Printer> The overall configuration of an inkjet printer according to an embodiment of the present invention will be described below with reference to FIGS. 1 to 4. Here, FIG. 1 is an external perspective view of an apparatus main body of the inkjet printer (hereinafter abbreviated as “printer”) 100, FIG. 2 is the same exploded perspective view, FIG. 3 is the same side sectional view, and FIG. It is a figure.

In FIG. 1 and FIG. 2, the printer 100 is divided into a plurality of units, and the plurality of units are combined to form a main unit. In the figure, reference numeral 1 is a paper feeding unit as a paper feeding device capable of feeding a paper P (see FIG. 3) as a recording material or roll paper (not shown), and reference numeral 120 is an inkjet recording head 124 (see FIG. 3) (see 3)
2 is a carriage unit including a sheet P
2, a reference numeral 180 denotes an ink system unit for maintaining the ink jet recording head 124, and the main body of the printer 100 is divided into these four units as shown in FIG. It is constructed by combining two units as shown in FIG.

In the present embodiment, the carriage unit 120 and the ink system unit 180 are connected to the upper side and the right side (the right side in FIG. 4) of the transport unit 160, and the paper feeding unit 1 is the rear surface of the carriage unit 120. The four units are configured to be united by connecting to the side.

Next, referring to FIG. 3, the printer 100
The paper transporting route will be described. In addition, in the following, FIG.
The left side (rear side of the printer 100) is referred to as “upstream side”, and the right side of FIG. 3 (front side of the printer 100) is referred to as downstream side. The printer 100 is provided with a hopper 6 on the upstream side, and the sheets P as cut sheets are stacked and held on the hopper 6 in an inclined posture. The hopper 6 has a rotating shaft 6a located at the top.
It is provided so as to be rotatable in the clockwise direction and the counterclockwise direction in FIG. 3 centering on (see FIG. 7), and the lower portion is brought into pressure contact with and separated from the sheet feeding roller 3 by the rotation. . Further, the hopper 6 is provided with a movable guide 4 that can slide in the width direction of the paper P (see FIG. 1), and a fixed guide 5 (see FIG. 1).
(See reference), the side edge of the accumulated paper P is guided.
Then, the topmost one of the accumulated sheets P is the hopper 6
Performs a pressure contact operation with respect to the paper feed roller 3, and in the pressure contact state, the paper feed roller 3 rotates and is fed to the downstream side. The paper feed roller 3 has a substantially D-shape when viewed from the side, and is controlled so that its flat portion faces the paper P during the printing operation (state of FIG. 3), whereby the paper P
It is designed to prevent the occurrence of transporting load.

The length of the arc portion of the paper feed roller 3 is such that the paper P is fed out from the hopper 6, and the leading end of the fed paper P is at the nip point between the transport drive roller 162 and the transport driven roller 163. From the length that can be reached, that is, from the pressure contact between the paper feed roller 3 and the paper P, the conveyance drive roller 16
2 is set so as to be longer than the length of the feeding path to the nip point between the transport driven roller 163 and the transport driven roller 163. Thus, for example, in FIG.
In order to stack a larger number of sheets of paper P on the hopper 6, it is necessary to move the arrangement position of the paper feed roller 3 to the upper position (upper left) in FIG. By increasing the diameter of the paper roller 3 (diameter 48 mm in this embodiment), it is possible to cope with the change in the feeding path length due to the upward movement of the arrangement position of the paper feeding roller 3. Becomes

Next, a paper guide 167 as a plate-like member is provided substantially horizontally below the paper feed roller 3, and the front end of the paper P fed out by the paper feed roller 3 is the paper guide 1.
It obliquely abuts 67 and is smoothly guided to the downstream side. A conveyance driving roller 162 that is rotationally driven and a conveyance driven roller 163 that is in pressure contact with the conveyance driving roller 162 are provided downstream of the paper guide 167, and the paper P is the conveyance driving roller 162 and the conveyance driven roller 163. Is nipped in
It is transported to the downstream side at a constant pitch.

The transport driven roller 163 is axially supported on the downstream side of the transport driven roller holder 164, and the transport driven roller holder 164 rotates in the clockwise direction and the counterclockwise direction in FIG. 3 around the rotation shaft 164a. The transport driven roller 163 is rotatably biased in a direction in which the transport driven roller 163 is constantly in pressure contact with the transport drive roller 162 (clockwise direction in FIG. 3) by a torsion coil spring (not shown).

Next, in the vicinity of the conveyance driven roller holder 164 located closest to the 0th digit side (the right front side in FIG. 2), the sensor body 136b and the detector 136 for detecting passage of the paper P are detected.
A sheet detector 136 including a and a is provided. The detector 136a has a substantially V shape when viewed from the side, and is provided so as to be rotatable clockwise and counterclockwise in FIG. 2 about a rotary shaft 136c near the center thereof. Detector 136a
The sensor body 136b located above the sensor includes a light emitting portion (not shown) and a light receiving portion (not shown) that receives light from the light emitting portion, and the upper side of the rotation axis 136c of the detector 136a is the rotation. By the dynamic operation, the light traveling from the light emitting unit to the light receiving unit is blocked and passed.

Therefore, as shown in FIG. 3, when the detector 136a is rotated so as to be pushed upward with the passage of the sheet P, the upper side of the detector 136a is located above the sensor body 136b.
, The light receiving portion is brought into a light receiving state, and the passage of the paper P is detected.

Subsequently, the platen 166 and the ink jet recording head 12 are provided downstream of the transport driving roller 162.
4 are arranged so as to face each other vertically. Platen 16
6 is long in the main scanning direction (see FIG. 2), and is the conveyance drive roller 1
The sheet P conveyed below the inkjet recording head 124 by the rotation of 62 is supported by the platen 166 from below. The ink jet recording head 124 is provided at the bottom of a carriage 122 carrying an ink cartridge 123, and the carriage 122 reciprocates in the main scanning direction while being guided by a carriage guide shaft 125 extending in the main scanning direction.

In this embodiment, the ink cartridge 123 has four cartridges as shown in FIG.
It consists of four cartridges filled with four color inks (black, yellow, cyan, and magenta) independently, and each cartridge can be replaced independently.

Next, a sheet discharge section of the printer 100 is provided downstream from the ink jet recording head 124, and a sheet discharge drive roller 165, a sheet discharge driven roller 131, and a sheet discharge auxiliary roller 132 are arranged. . Paper ejection drive roller 16
A plurality of discharge driven roller holders 5 5 are attached to the discharge frame 130, and a plurality of discharge driven roller shafts 165a are attached in the axial direction of the discharge driving roller shaft 165a (see FIG. 4).
The paper discharge driven roller 131 pivotally supported by a is provided so as to be driven to rotate by being slightly pressed against the paper discharge drive roller 165. Therefore, the inkjet recording head 12
The paper P that has been printed by the paper 4 is ejected by the paper ejection drive roller 1
When the sheet discharge driving roller 165 rotates while being nipped by the sheet discharge roller 65 and the sheet discharge driven roller 131, the sheet is discharged in the sheet discharge direction (the arrow direction in FIG. 3).

The paper ejection auxiliary roller 132 pivotally supported by the paper ejection auxiliary roller holder 132a is a paper ejection driven roller 131.
The sheet P and the inkjet recording head 124 are provided on the slightly upstream side of the sheet P to prevent the sheet P from floating from the platen 166 by pressing the sheet P slightly downward.
The distance to and is regulated.

The hopper 6, the movable guide 4, the fixed guide 5, and the paper feed roller 3 described above are provided in the above-described paper feed unit 1 shown in FIGS. 1 and 2. As shown in FIG. 2, the sheet feeding unit 1 includes a mounting portion right 2a and a mounting portion left 2 which are vertically arranged on both sides of a hopper 6 and have a substantially columnar shape.
The paper feeding unit frame 2 having a sheet feeding unit frame 2 has a base body, and the paper feeding roller shaft 3a, which is the rotation shaft of the hopper 6, the paper feeding roller 3, and the like.
It is provided in. Then, the paper feeding unit 1 is connected to the rear surface side of the carriage unit 120 at the upper part of the mounting portions 2a and 2b. The paper feeding unit 1
A more detailed configuration of the above will be described later.

Next, the paper guide 167, the transport drive roller 162, the transport driven roller holder 164, and the paper discharge drive roller shaft 165a are the transport unit 160 shown in FIGS.
It is provided in. As shown in FIG. 2, the transport unit 160 has a base body constituted by a transport unit frame 161 having a substantially U-shape in a plan view, and the printer 100 is provided at the rear side.
Power supply unit 168, which is a power supply unit of the above, and supports the discharge drive roller shaft 165a in the front, the transport drive roller 162 in the middle of the main body, the platen 166 in the front upper part, and the transport follower in the middle upper part. Roller holder 164
Is equipped with.

The transport unit 160 is located on the lower left side,
A drive motor 16 serving as a common drive source for the paper feed roller 3, the conveyance drive roller 162, the paper ejection drive roller 165, a pump device 182, and a blade unit 184 described later.
9 (see FIG. 4). The drive motor 169 and the five drive targets driven by the drive motor 169 are connected by a power transmission mechanism whose illustration and description are omitted in a state where the four units are combined as shown in FIG. 1. Moreover, it can be selectively driven.

The ink system unit 180, which is connected to the right side portion of the transport unit 160 and serves as a maintenance means for the ink jet recording head 124, is connected to the right side surface of the transport unit frame 161 as shown in FIG. Is provided with a frame 181, and a cap device 183 and a pump device 18 are attached to the frame 181.
2. The blade unit 184 is provided. In the cap device 183, the carriage 122 is at the home position (see FIG.
Of the ink jet recording head 24 to protect the nozzle surface (not shown) when moved to the right side region of the pump device 182.
A negative pressure is supplied to the nozzle 3, and ink is sucked from the nozzle openings of the inkjet recording head 124.

The blade unit 184 is movable between a position where it crosses the reciprocating region of the carriage 122 and a position where it retracts from the reciprocating region.
When the carriage 122 moves to a position that traverses the reciprocating region 2 and the carriage 122 moves from the print region to the home position (the right side region in FIG. 4) or in the opposite direction, the ink jet recording head 124 moves. Cleaning is performed by wiping the nozzle surface (not shown).

The carriage guide shaft 125 and the paper detector 136 are provided in the carriage unit 120. As shown in FIG. 2, the carriage unit 120 includes a main frame 121a, a side frame right 121b and a side frame left 121c that are erected on both sides of the main frame 121a. 125 is pivotally supported.

Further, as shown in FIG. 4, the carriage unit 120 is provided with a carriage motor 127 on the rear surface on the left side of the unit, and the carriage motor 127 has a drive pulley 128.
Is attached. A driven pulley 129 is provided on the right side of the unit, and the driven pulley 128 and the driven pulley 1 are provided.
A carriage belt 126 is hung between the carriage belt 126 and the carriage 29.
It is fixed to 22. Therefore, the carriage 122 is rotated in the main scanning direction (see FIG. 4) by the rotation of the carriage motor 127.
To the left and right).

Although the paper discharge frame 130 is attached to the carriage unit 120 side in FIG. 2, the paper discharge frame 130 can be attached to the carriage unit 120 side or the transport unit 160 side. It is possible to belong to either side. The above is the configuration of the apparatus main body of the printer 100, and the printer 100 becomes movable by combining and connecting the four units.

<Detailed Structure of Paper Feed Unit> Next, referring to FIG.
The detailed configuration (overall configuration) of the sheet feeding unit 1 will be described with reference to FIGS. Here, FIG. 5 is an external perspective view of the paper feeding unit 1, FIG. 6 is a front view thereof, FIG. 7 is a sectional view of the same side, and FIGS. 8A and 8B show the paper feeding roller 3 and the paper feeding auxiliary roller 15. 9 is a side view and a front view thereof, and FIG. 9 is an explanatory view (partially enlarged view of FIG. 7) of a plunging angle of the paper P into the separation pad 8.

First, as described above, the paper feeding unit 1 has the base body constituted by the paper feeding unit frame 2, and the transmission gear unit 17 is provided on the left side surface (left side in FIG. 6) of the paper feeding unit frame 2 and the right side surface thereof. On the right side in FIG. 6, a hopper release means, which will be described later, including a rotary cam 20 is provided, and a paper feed roller shaft 3a is provided between them.

The transmission gear unit 17 is in a state in which the sheet feeding unit 1 is connected to the carriage unit 120 (see FIG. 1).
In (1), it meshes with a transmission gear (not shown) of the transport unit 160 and transmits the turning force of the drive motor 169 (see FIG. 4) attached to the transport unit 160 to the paper feed roller shaft 3a. Therefore, the paper feeding unit 1 (paper feeding roller shaft 3a)
Uses a drive motor 169 that is a drive source for the transport drive roller 162 and the like as a power source, and as a result, does not have its own drive source, and thus the sheet feeding unit 1 is configured at low cost. Then, the paper feed roller shaft 3a transmits the turning force applied to the left end by the transmission gear device 17 to the hopper release means (described later) provided on the right end. Therefore, the paper feed roller shaft 3a in the present embodiment not only functions as a rotation shaft of the paper feed roller 3 but also as a power transmission shaft.

As shown in FIG. 6, one paper feed roller 3 is rotatably driven by the paper feed roller shaft 3a, and is provided at the right end, that is, at a position distant from the transmission gear device 17. Here, the paper feed roller 3 has a substantially D-shape in a side view as described above, and as shown in FIGS.
A roller body 3 integrally formed with a by resin molding
c and a rubber material 3b as an "elastic member" that is wound around the outer periphery of the roller body 3c, and the rubber material 3b secures a coefficient of friction with the paper P. The paper P pressed against the roller 3 is reliably fed without slipping.

In this embodiment, EPDM (ethylene propylene rubber) is used as the rubber material 3b. Further, the paper feed roller shaft 3a is provided with a paper feed auxiliary roller 15 having a substantially D-shape in a side view as seen in the axial direction between the left end of the paper feed roller shaft 3a and the paper feed roller 3. This will be described later in detail.

Next, as described above, the paper supply unit 1 is provided with the hopper 6 made of a plate-like member elongated in the width direction of the paper P in an inclined posture as shown in FIG. As described above, the hopper 6 is provided so as to be rotatable in the clockwise direction and the counterclockwise direction in FIG. 7 about the rotation shaft 6a, and the lower portion of the rear side of the hopper 6 is the lower portion of the hopper 6 and the paper feed roller. A compression coil spring 7 is provided as a "biasing means" for urging the hopper 6 so that the hopper 6 is constantly urged to rotate in a direction in which the hopper 6 is pressed against the paper feed roller 3. The paper feeding unit 1 is a hopper 6
Has a "hopper release means" for rotating the paper feed roller 3 in a direction away from the paper feed roller 3. The configuration and operation and effect of the hopper release means will be described in detail later.

Next, a separation pad holder 9 and a guide member 13 are provided below the hopper 6. The separation pad holder 9 is arranged at a position facing the paper feed roller 3 as shown in FIG. 6, and holds the separation pad 8 made of a friction member so as to face the paper feed roller 3 as shown in FIG. There is.
In addition, the separation pad holder 9 has a rotation shaft 9a as a center.
Is provided so as to be rotatable in the clockwise direction and the counterclockwise direction, and the separation pad 8 is biased by the compression coil spring 10 in a direction in which the separation pad 8 is pressed against the sheet feeding roller 3. Therefore, when the paper feed roller 3 is rotated from the state shown in FIG. 7 (the state where the separation pad 8 and the flat portion of the paper feed roller 3 face each other), the separation pad 8 comes into contact with the arc portion of the paper feed roller 3. It is designed to be pressed.

The separation pad 8 provided in the separation pad holder 9 clamps the uppermost sheet P, which abuts (enters) the separation pad 8 at an abutment angle α, with the paper feed roller 3. The double feeding of the paper P after the next one is prevented. More specifically, if the friction coefficient between the paper feed roller 3 and the paper P is μ ₁ , the friction coefficient between the paper P is μ ₂ , and the friction coefficient between the paper P and the separation pad is μ ₃ , then μ ₁ > μ ₃ >
The materials of the rubber material 3b and the separation pad 3 are selected so that the relationship of μ ₂ is established. Accordingly, the uppermost sheet P to be fed is reliably delivered to the downstream side according to the rotation of the sheet feeding roller 3, and the next and subsequent sheets P are retained in the separation pad 8, and Double feeding of P is prevented.

A holding pad 6b is provided below the hopper 6 at a position facing the sheet feeding roller 3 and a sheet feeding auxiliary roller 15 which will be described later. The holding pad 6b holds the holding pad 6b on the hopper 6. The bundle of stacked sheets P is held so as not to move downstream together with the bundle when the uppermost sheet P is fed.

By the way, the contact angle α in this embodiment is
The fluctuation range is the rotation that determines the swing angle of the hopper 6.
Arrangement position of the shaft 6a and dimension of the hopper 6 in the feeding direction (paper P
The lengthwise dimension of is set as follows. Immediately
If the hopper 6 is farthest from the paper feed roller 3,
The uppermost sheet P comes into pressure contact with the sheet feeding roller 3.
The angle at which the paper P is piled up on the hopper 6
Of the paper P, which causes the leading edge of the paper P to separate.
The contact angle α that contacts the pad 8 also changes. Figure 9 is like this
(A) shows the maximum number of sheets of paper P that can be set.
Contact angle α when_max(B) shows the paper P
Contact angle α when the minimum set number is approximately _minShows
It is a thing. As is clear from the figure, the number of sheets of paper P set
The larger the number, the larger the contact angle α. In addition, in FIG.
Sign P₁Is the top sheet, and the code P_TwoIs the paper P
₁Shows the next one.

However, in FIG. 9A, the contact angle α
_maxIs the maximum value α of the contact angle through which the topmost paper P can pass
₁Being bigger than the top
Paper P₁Is caught in the separation pad 8 and is not fed
The state also occurs. On the contrary, the contact angle α _minDouble feed of paper P
Minimum value of contact angle that can prevent_TwoLess than
Then, the next paper P_Two(Alternatively, the paper P_TwoIncluding
Multiple sheets of paper P) to be fed next to
Paper P₁And the separation pad 8 and then double-fed
The situation may occur. Therefore, in this embodiment, the contact
The angle α is independent of the number of sheets of paper P accumulated on the hopper 6.
Without α_Two≤α ≤α₁Of hopper 6 to maintain the relationship
The position of the moving shaft 6a and the dimension of the hopper 6 in the feeding direction are set.
Has been done. Therefore, regardless of the number of stacked sheets of paper P,
Contact angle α_maxIs the upper limit α₁Not exceed, and
Contact angle α_minIs the lower limit α_TwoSince it does not fall below
It is designed so that an appropriate paper feeding operation can always be performed.

In this embodiment, the length of the hopper 6 in the feeding direction is about 130 mm, and the swing angle of the hopper 6 is about 1.
It is 0 deg. However, in this case, the paper P
When the maximum number of sheets is set, the swing angle of 2 deg of the hopper 6 until the uppermost sheet P comes into pressure contact with the sheet feeding roller 3 is not included.

Next, the guide member 13 will be described.
As shown in FIG. 6, one guide member 13 is provided with two smooth guide surfaces 13a (see FIG. 7) for guiding the paper P to the downstream side at a predetermined distance in the width direction of the paper P. Two guide members 13 having one guide surface 13a are provided at a predetermined interval in the width direction of the paper P. Further, the guide member 13 is provided with an abutting surface 13b, which is connected to the guide surface 13a, with which the leading ends of the sheets P stacked and held in an inclined posture abut substantially vertically (see FIG. 7). The contact surface 13b
Is formed by a circular arc (curved surface) centering on the rotation shaft 6a of the hopper 6, and the leading end of the paper P accumulated and held in the hopper 6 in an inclined posture causes the contact surface to move as the hopper 6 rotates. It is designed to slide on 13b.

If the friction coefficient between the contact surface 13b and the leading edge of the paper P is large, the hopper 6 is rotated to bring the uppermost paper P into pressure contact with the paper feed roller 3. Since it takes time and may adversely affect the paper feeding operation, it is desirable that the friction coefficient is as low as possible (for example, μ <0.3). Therefore, in this embodiment, the guide member 13 is formed by resin molding using POM (polyoxymethylene) or AES (acrylonitrile ethylene styrene), and the contact surface 1
A low friction coefficient is realized by applying a lubricant to 3b. The separation pad holder 9 also has a similar contact surface 9b.

Next, as shown in FIGS. 5 and 6, a paper feed auxiliary roller 15 is provided between the paper feed roller 3 and the transmission gear unit 17 on the paper feed roller shaft 3a. As described above, the paper feed auxiliary roller 15 has a substantially D-shape when viewed from the side in the axial direction of the paper feed roller shaft 3a, and like the paper feed roller 3, is integrally formed with the paper feed roller shaft 3a by resin molding. And a rubber material 15b as an "elastic member" wound around the outer periphery of the roller body 15c.
And the rubber material 15b,
The print surface of the paper P is prevented from being scratched.

The paper feed auxiliary roller 15 thus constructed
Performs the following two functions in the sheet feeding unit 1 according to the present embodiment. First of all, the paper P
Fulfills the function of regulating the feeding posture of. That is, since the paper feed roller 3 and the separation pad 8 are provided as a pair,
It is desirable to provide only one pair of the paper feed roller 3 and the separation pad 8 as in the present embodiment in order to reduce the cost. However, in order to accommodate various sizes of paper P, in particular, the size in the width direction is small. In order to deal with the paper P, the paper feed roller 3 and the separation pad 8 are provided at positions offset to the 0th digit side (right side in FIG. 6).

However, as shown in FIG. 3, the sheet feeding unit 1 has a structure in which the sheet P is curved by the sheet feeding roller 3 so as to be convex downward, and the sheet is fed. If the sheet P is provided at a position biased to the side, the sheet P does not curve uniformly in the width direction, that is, the side on which the sheet feeding roller 3 is not provided (the left side in FIG. 6) feeds the sheet. The roller 3 is not curved as compared with the side on which the roller 3 is disposed, and as a result, a difference in the left and right advancement at the leading edge of the sheet P may occur, causing a so-called skew (skew). Therefore, by providing the paper feed auxiliary roller 15 on the side where the paper feed roller 3 is not provided, the curving posture of the paper P is regulated so as to be uniform, thereby realizing a normal paper feed operation. There is.

Here, the paper feed auxiliary roller 15 has a substantially D-shape in side view like the paper feed roller 3 and is formed with the same diameter as the paper feed roller 3, but in the D shape. The flat portion has a shape that is cut further than the paper feed roller 3. FIG. 8A shows this. As shown in the figure, the flat portion of the sheet feeding auxiliary roller 15 is closer to the rotation center side than the flat portion of the sheet feeding auxiliary roller 3 (the sheet feeding roller shaft 3).
The shape is trimmed to the a side (for example, 4 with respect to the diameter 48 mm of the paper feed roller 3 and the paper feed auxiliary roller 15).
mm).

The reason for this will be described below. Paper P
In order to reduce the conveyance load (rotational load of the conveyance driving roller 162 (see FIG. 3)) during the conveyance (printing operation) of the sheet feeding roller 3 (and the sheet feeding auxiliary roller), as shown in FIG. 15)
It is assumed that the flat portion of the sheet P faces the sheet P. Here, as shown in FIG. 8B, paper return levers 12 and 12 are disposed below the paper feed roller 3 (see also FIG. 7), and the paper P
8 is in a state of being slightly bent by the paper feed roller 3 and the paper return levers 12 and 12 when viewed in the width direction, as shown in FIG. 8B. At this time, the feeding auxiliary roller 1
When the shape of 5 is the same as that of the paper feed roller 3, the paper P is further bent in a convex shape as shown by the broken line in FIG.
Rigidity of paper P and paper feed roller 3, paper feed auxiliary roller 15,
The friction of the paper return lever 12 causes a problem that the transport load increases. Therefore, by making the shape of the paper feed auxiliary roller 15 different from that of the paper feed roller 3 as described above, unnecessary bending of the paper P is not given, and an increase in conveyance load is prevented.

By the way, the paper P shown by imaginary lines in FIG. 6 shows a state in which A4 size paper is set vertically, and in the present embodiment, the paper feed roller 3 and the paper feed auxiliary roller 15 are illustrated. A4 size paper P
Are evenly arranged according to the width dimension of. Accordingly, the feeding attitude of the A4 size paper P, which is generally used frequently, can be regulated most uniformly, and the effect of the paper feed auxiliary roller 15 that regulates the feeding attitude of the paper P can be most efficiently achieved. It is possible to play. However, the arrangement position of the paper feed auxiliary roller 15 is not limited to this embodiment as long as it is a position where the paper P can be normally fed, that is, a position where the feeding posture of the paper P can be regulated. It doesn't matter even where

Secondly, the paper feed auxiliary roller 15 functions as a "twist suppressing member" for suppressing the twist of the paper feeding roller shaft 3a. That is, as described above, the feed roller shaft 3a is given a turning force by the transmission gear device 17 provided on the left side of the apparatus (left side of FIG. 6), and the right side of the apparatus (FIG. 6).
It functions as a power transmission shaft for transmitting power to a hopper release means, which will be described later, provided on the right side of FIG. Therefore, a load is applied to the paper feed roller shaft 3a during power transmission to the hopper release means or during a paper feed operation by the paper feed roller 3, which causes twisting. When the paper feed roller shaft 3a is twisted, a phase shift occurs in the rotation operation of the paper feed roller 3 or the operation of the hopper release means to which power is supplied, and normal paper feed operation and power transmission cannot be performed. The problem arises. Particularly, since the paper feed roller 3 is provided at a position biased farther from the shaft end (left side in FIG. 6) of the paper feed roller shaft 3a to which rotational force is applied, the influence of the twisting is further increased. It is easy to receive.

However, since the paper feed auxiliary roller 15 is provided on the paper feed roller shaft 3a, the twist in the portion where the paper feed auxiliary roller 15 is provided is reduced, and as a result, the twist is generated. It is possible to reduce the problem of phase shift. It is possible to further enhance the operational effect by further providing such a twist suppressing portion at other positions as appropriate, and at that time, the shape thereof need not be the same as that of the sheet feeding roller 3. Any shape may be used as long as it has a larger radial dimension than the paper feed roller shaft 3a. In addition, in the present embodiment, the paper feed roller shaft 3a, the paper feed roller 3 (the roller body 3
c), the paper feed auxiliary roller 15 (roller body 15c) is AB
It is possible to integrally form them by resin molding using the S resin, thereby obtaining them at low cost, and by molding them integrally, it is possible to further obtain the above-described twist suppressing effect.

It should be noted that, for example, the paper feed auxiliary roller 15 and the paper feed roller shaft 3a are formed separately and independently.
Even if is attached to the paper feed roller shaft 3a by an adhesive means or the like, it is possible to obtain a predetermined twist suppressing effect by the adhesive effect.

By the way, the rubber material 15b is wound around the outer peripheral portion of the sheet feeding auxiliary roller 15 as described above. The rubber material 15b is made of EPDM (ethylene propylene rubber) in the present embodiment like the rubber material 3b wound around the outer periphery of the paper feed roller 3, but the EPD of the rubber material 3b described above is used.
An additive is further added to M, whereby the tensile strength is improved. Hereinafter, the tensile strength of the rubber material 15b wound around the paper feed auxiliary roller 15 in this manner will be described with reference to the rubber material 3b wound around the paper feed roller 3.
The significance of further improvement will be explained.

First, it is desirable to wind an elastic member around the outer peripheral portion of the paper feed auxiliary roller 15 from the viewpoint of protecting the printing surface of the paper P as described above, but from the viewpoint of cost reduction, the paper feed roller 3 is used. It is not desirable to use the same width as. However, if the width of the paper feed roller 3 is smaller than that of the paper feed roller 3,
The strength is lowered as a whole, and the following problems occur. That is, a guide member 13 that smoothly guides the paper P to the downstream side is provided at a position facing the paper feed auxiliary roller 15 as shown in FIG. 7, and two guide surfaces 13a are provided as shown in FIG. , 13a is provided with a paper feed auxiliary roller 15. Therefore, when a large number of sheets P are fed in such a configuration, the bundle of sheets P is fed by the sheet feeding auxiliary rollers 15 and 2.
A state in which it is clamped between the two guide surfaces 13a, 13a,
In other words, it becomes a paper jam.

Here, when the paper feeding unit 1 is configured to control the paper feeding roller 3 to stop when, for example, a paper jam occurs, a drive motor 169 for rotating the paper feeding roller 3 (see FIG. 4). Since the paper feed roller shaft 3a does not rotate when pulling out the sheet bundle that has become a paper jam, the rubber material 15b may tear if the sheet bundle is forcibly pulled out in this state. There may be problems that occur.

Therefore, by improving the tensile strength of the rubber material 15b wound around the paper feed auxiliary roller 15,
The paper feed auxiliary roller 15 and the two guide surfaces 13a, 13a
Even if a paper jam occurs between the paper jam and the paper jam that is the paper jam, the paper feed auxiliary roller 1
It is possible to prevent the occurrence of a trouble such as tearing of the rubber material 15b wound around the coil 5, and at the same time, reduce the size in the width direction to reduce the cost.

In the present embodiment, as shown in FIG. 6, the width of the paper feed auxiliary roller 15 is smaller than that of the paper feed roller 3, so that the cost of the rubber material 15b can be reduced and the paper feed auxiliary roller 15 can be used. The peripheral space of the paper feed unit 1 is connected to the carriage unit 120 (see FIG. 1) to increase the degree of freedom in arranging the components of the carriage unit 120. The roller body 15c has the same width as or larger than that of the paper feed roller 3, and the width of the rubber material 15b wound around the outer peripheral portion is left unchanged, whereby the above-mentioned paper feed roller shaft 3a is formed.
It is possible to further obtain the effect of suppressing the twist of the sheet and, at the same time, obtain the various functions and effects of the sheet feeding auxiliary roller 15 described above.

Further, the paper feed roller 3 and the paper feed auxiliary roller 1
The elastic member wound around the outer peripheral portion of 5 is not limited to this embodiment (rubber material: EPDM), and other materials such as butyl rubber may be used. That is, the paper feed roller 3 can secure a friction coefficient capable of normally feeding the paper P, and the paper feed auxiliary roller 15 can protect the printing surface of the paper P and can be manufactured at low cost. However, it does not matter what kind.

Next, in FIG. 7, a paper pressing member 14 is provided at a position facing the hopper 6 so as to be rotatable about the rotation shaft 14a in the clockwise and counterclockwise directions in FIG. 7 (this embodiment). In the form, two are provided with the paper feed roller 3 interposed therebetween: not shown). The paper pressing member 14 has a function of lightly pressing the paper P accumulated on the hopper 6 from above by its own weight, thereby preventing the paper P accumulated on the hopper 6 from rising.

A paper return lever 12 is provided below the hopper 6 and is rotated by a cam mechanism (not shown) about the rotary shaft 12a (in the present embodiment, the paper feed roller 3 is Two pieces are provided so as to be sandwiched therebetween: see FIGS. 6 and 8B). The paper return lever 12 returns the paper P accumulated in the vicinity of the separation pad 8 provided for the purpose of preventing the double feeding to the hopper 6 as described above, and normally performs the paper feeding operation of the next paper P. Plays a function. The above is the detailed configuration of the paper feeding unit 1.

<Structure of Hopper Release Means> Next, referring to FIG.
0 to FIG. 13 and other drawings as appropriate,
The configuration of the hopper release means for rotating the hopper 6 in the direction away from the paper feed roller 3 will be described. here,
10 is a partially enlarged perspective view of the paper feeding unit 1.
FIG. 1 is a schematic diagram showing the acting position of an external force acting on the hopper 6. 12A is a front view of the rotary cam 20, FIG. 12B is a sectional view taken along line yy in FIG.
(A) is a front view of the cam lever holder 35, and (B) of the same figure is a side view (z arrow view in (A)).

As described above, the hopper release means is
Right side of the sheet feeding unit 1 (front side of FIG. 5: right side of FIG. 6)
It is provided in. In FIG. 5, a transmission gear 11 is attached to the right end of the paper feed roller shaft 3 a, and is formed on the rear side of the transmission gear 11 and a rotary cam 20 rotatably attached by a rotation shaft 21. Gear part 25
(See FIG. 12 (B)), and the rotary cam 20 is driven to rotate. That is,
The rotary cam 20 is configured to rotate in accordance with the rotation of the paper feed roller 3, and the hopper release means has a low cost without having its own drive source.

Since the transmission gear 11 directly meshes with the rotary cam 20 and the transmission gear 11 and the gear portion 25 are gears having the same number of teeth, therefore, when the paper feed roller 3 makes one rotation in the clockwise direction, Rotary cam 20 is counterclockwise 1
The relationship is such that they rotate.

On the other hand, below the rotary cam 20, there are provided a cam lever 30 and a cam lever holder 35 which can be swung according to the rotation of the rotary cam 20, and the hopper release means, which will be described in detail below, is the rotary cam 2
The release bar 16 (see FIG. 10) is configured to perform the engaging operation in the order of 0 → cam lever 30 → cam lever holder 35, and is engaged with the back side (right side in FIG. 7) of the hopper 6 by the swing operation of the cam lever holder 35. ) Is rotated, and thus the hopper 6 is rotated.
The above is the outline of the hopper release means.

The structure, operation and effect of the release bar 16 provided on the back side of the hopper 6 will be described below. As shown in FIG. 10, the release bar 16 has a substantially U-shaped shape, and extends from the first shaft portion 16b extending in the longitudinal direction of the hopper 6 (the width direction of the paper P) and one end of the first shaft portion 16b. Second shaft portion 16a extending vertically to the vicinity of the compression coil spring 7
And a third shaft portion 16c extending from the other end of the first shaft portion 16b substantially in parallel with the second shaft portion 16a.

As shown in FIG. 7, the release bar 16 has a sub-frame 19 having a V-shape in a side view.
By the bearing portion 18 provided above the first shaft portion 1
6b is pivotally supported, whereby the second shaft portion 16a and the third shaft portion 16c can rotate in the clockwise direction and the counterclockwise direction in FIG. 7 with the first shaft portion 16b as the rotation axis. There is.

On the other hand, on the rear side of the hopper 6, the second shaft portion 1
An engaging portion 6c (see FIG. 7) with which the tip of 6a is engaged is provided, and the cam lever holder 35, which will be described in detail later, has a third shaft portion 16c as shown in FIGS. 13 (A) and 13 (B). When the cam lever holder 35 is rotated in the clockwise direction and the counterclockwise direction in FIG. 13A, the recessed portion 44 is provided as the "hopper action portion" with which the bent front end portion of FIG. 16 is the first shaft portion 1
6b is rotated about a rotation axis, so that the hopper 6 swings. That is, the cam lever holder 35, the cam lever 30, and the rotary cam 20 constitute “release bar rotating means” for rotating the release bar 16.

By the way, the engaging position between the release bar 16 and the hopper 6, that is, the disposing position of the engaging part 16c and the disposing position of the compression coil spring 7 are substantially the same as shown in FIGS. Therefore, the point of action of the force applied by the release bar 16 to the hopper 6 and the point of action of the force applied by the compression coil spring 7 to the hopper 6 are located at substantially the same position in plan view of the hopper 6. Will be. Therefore, due to this, almost no bending moment is generated in the hopper 6,
The deformation of the hopper 6 is prevented, and thus the normal paper feeding operation can be maintained.

More specifically, as shown in FIG. 11, the hopper 6
Is a plate-like member that is long in the width direction of the paper P, so that the action point of the force (white arrow in FIG. 11) applied to the hopper 6 by the release bar 16 (second shaft portion 16a) and the compression coil spring 7 are the hopper. When the point of action of the force applied to 6 (black arrow in FIG. 11) does not coincide with the left-right direction in FIG. 11 and the front-back direction of the paper surface, that is, on the plane of the hopper 6, the hopper 6 has a bending moment. Occurs, which causes the hopper 6 to be temporarily or in a future curved state. When the hopper 6 is curved as described above, various problems such as a decrease in the maximum number of sheets of the paper P to be set or a skew (skew) when the paper P is fed will occur.

However, as described above, in the sheet feeding unit 1, the point of action of the force applied by the release bar 16 to the hopper 6 and the point of action of the force applied by the compression coil spring 7 to the hopper 6 are shown in FIG. As described above, since the hopper 6 is configured to be located at substantially the same place on the plane, the bending moment is hardly generated in the hopper 6, the deformation of the hopper 6 is prevented, and the normal feeding operation is maintained. In addition, since the action points of the forces coincide with each other on the hopper 6, it is possible to stably perform the high-speed swing operation of the hopper 6.

Next, the rotary cam 20, the cam lever 30, and the cam lever holder 35 as the release bar rotating means for rotating the release bar 16 will be described. First, as shown in FIG. 12 (A), the rotary cam 2
Reference numeral 0 denotes a disc-like member that is rotated by inserting the rotation shaft 21 (see FIG. 5) into the shaft hole 21a in a front view, and is formed in a step shape protruding from the outer periphery toward the shaft hole 21a in a stepwise manner. The cam portion (the range shown by the area in FIG. 12A) is provided. The stepped cam portion is composed of fan-shaped cams 22a to 22e that are fan-shaped in a front view and that engage with the cam lever 30 on the outer peripheral surface. And
A guide surface 23 that guides the cam lever 30 to the outer peripheral surfaces of the fan-shaped cams 22a to 22e adjacent to the fan-shaped cam 22a.
a and the fan-shaped guide surfaces 23b to 23e, and further the guide surface 2
3a and the fan-shaped guide surfaces 23b-23e, the cam lever 30
Cam slopes 24a to 24c for guiding the cam lever 30 to guide the cam lever 30 to the outer peripheral surface of one of the fan-shaped cams (22a to 22e) corresponding to the accumulated amount of the paper P (see FIG. 12A). Range indicated by area)
Are formed.

Guide surface 23a and fan-shaped guide surface 23b
23e is located on the inner peripheral side of the rotary cam 20 step by step with respect to the outer peripheral surfaces of the fan-shaped cams 22a to 22e, whereby the cam lever 3 on the fan-shaped guide surface 23c, for example.
0 indicates rotation of the rotary cam 20 from the state (see FIG. 12).
By (counterclockwise direction of (A)), the outer peripheral surface of the fan-shaped cam 22b is engaged (pressed). The fan-shaped guide surfaces 23b to 23e are formed in a spiral shape having different phases (starting points of arcs) as shown in FIG.

The guide slopes 24a to 24c are used for the non-cam portion 2
The cam lever 30 located at 6 (described later) is attached to the guide surface 23a.
And plays a function of guiding the fan-shaped guide surfaces 23b to 23e. As shown in FIG. 5, the guide slope 24a gradually rises in the clockwise direction of the rotary cam 20 and has a uniform radial height (the left side is higher in FIG. 12B), and then the inner peripheral side. Are connected to the fan-shaped guide surface 23e at substantially the same height, and the fan-shaped guide surface 23e is formed at the center in the radial direction.
Fan-shaped guide surfaces 23b, 23c, 2 located at a lower position than
The guide slope 24c is connected to the guide slope 24b that slides down to 3d, and slides down to the guide face 23a on the outer peripheral side.
Connected with.

Next, a non-cam portion 26 having a flat disk surface is provided adjacent to the fan-shaped cams 22a to 22e (range indicated by a region in FIG. 12A). The non-cam portion 26 does not constrain the cam lever 30 in the radial direction of the rotary cam 20. Therefore, for example, the cam lever 30 in the engagement state with the fan-shaped cam 22a located on the outermost peripheral side rotates the rotary cam 20 from that state. When it enters the area of the non-cam portion 26 (counterclockwise in FIG. 12A), the uppermost sheet P is pressed against the sheet feeding roller 3 by the urging force of the compression coil spring 7 shown in FIG. The rotary cam 20 is displaced toward the center of rotation until the state is reached. On the contrary, the cam lever 30 in the area of the non-cam portion 26 has a cam surface 2 that smoothly follows the outer peripheral surface of the fan-shaped cam 22a when the rotary cam 20 rotates clockwise from the above state.
While being guided by 6a, it is guided to the outer peripheral surface of the fan-shaped cam 22a located on the outermost peripheral side.

Next, referring to FIG. 13, the cam lever holder 3
Reference numeral 5 denotes an arm shape composed of an arm portion 39a extending from a shaft hole 40 that passes through the rotation shaft 36 (see FIG. 5) and an arm portion 39b that is turned from the arm portion 39a and extends obliquely upward.
It is attached to the paper feeding unit frame 2 so as to be rotatable around the shaft hole 40. Further, the cam lever holder 35 is provided with a spring retaining portion 43, and the sheet feeding unit frame 2 side is also provided with a similar spring retaining portion (not shown), and a tension coil spring is provided between them. 37 is suspended (see FIG. 5). The tension coil spring 37 exerts a spring force such that the cam lever holder 35 rotates in the clockwise direction in FIG. 13, whereby the protrusion 38 causes the release bar 16 to move.
It is designed so that it will always be in contact with.

Here, in FIG. 13 (A), when the cam lever holder 35 rotates clockwise in the drawing, the release bar 16 (third shaft portion 16c) rotates counterclockwise in the drawing, which causes the hopper to rotate. 6 rotates in a direction away from the paper feed roller 3. At this time, the cam lever holder 35 is
The hopper 6 is rotated against the spring force of the compression coil spring 7 (see FIG. 7). On the other hand, when the cam lever holder 35 rotates in the counterclockwise direction in the figure, the release bar 16 (third shaft portion 16c) rotates in the clockwise direction in the figure, so that the hopper 6 is pressed against the sheet feeding roller 3. Rotate. At this time, the release bar 16 and the cam lever holder 35 are rotated by the spring force of the compression coil spring 7 (see FIG. 7).

The cam lever 30 has a rotary shaft 32, and the rotary shaft 32 is formed on the cam lever holder 35.
1 and 41 are rotatably supported, and are shown in FIGS.
As shown by the phantom line in (B), it is swingable in the axial direction of the rotary cam 20. Further, a spring retaining portion 33 is provided on the cam lever 30 side, a hole 42 is provided on the cam lever holder 35 side, and a torsion coil spring 31 is provided between them. Therefore, the cam lever 30
Is attracted to the rotary cam 20 side by the spring force of the torsion coil spring 31.
Is always in contact with.

Rotary cam 2 constructed as described above
0, the cam lever 30, and the engagement operation of the cam lever holder 35 will be outlined. First, in FIG. 12 (A),
The cam lever is a fan-shaped cam 2 as indicated by the phantom line and reference numeral 30.
A case where the rotary cam 20 is in pressure contact with the outer peripheral surface of 2a and the rotary cam 20 makes one rotation (360 °) from the state will be described.

When the cam lever 30 is located on the fan-shaped cam 22a, as is apparent from FIG.
5 is located at the most clockwise position, so that the hopper 6 is in the most separated state from the paper feed roller 3. When the rotary cam 20 rotates counterclockwise in FIG. 12A, the cam lever 30 is disengaged from the fan-shaped cam 22a and enters the area (area) of the non-cam portion 26 toward the center of rotation of the rotary cam 20. The displacement works. When the cam lever 30 is displaced toward the center of the rotary cam 20 in this way, the cam lever holder 35 rotates counterclockwise in FIG. 13A, and the hopper 6 is fed by the biasing force of the compression coil spring 7. It rotates in the direction in which it comes into pressure contact with the roller 3.

Here, the paper P set on the hopper 6
Since the swing angle of the hopper 6 becomes smaller when the accumulation amount of the hopper is larger, the cam lever 30 in this case is the fan-shaped cam 22a.
Even if it deviates from the above position, the small displacement operation is performed toward the center of rotation of the rotary cam 20. On the other hand, if the accumulation amount of the sheets P set on the hopper 6 is small, the swing angle of the hopper 6 becomes large. Therefore, in this case, the cam lever 3
0 is the rotary cam 2 after it is disengaged from the fan-shaped cam 22a.
A large displacement operation is performed toward the center of rotation of 0.

The rotary cam 20 is further shown in FIG.
When rotated in the counterclockwise direction (A), the cam lever 30 enters the cam lever guide portion (region), and the guide slope 24a.
To engage with. At this time, the cam lever 30 swings in the axial direction of the rotary cam 20 while the radial cam 20 is not displaced in the radial direction (FIG. 12B).
And the fan-shaped guide surface 23e and the guide slope 24.
b (then, the fan-shaped guide surfaces 23b to 23d) and the guide slope 24c (then, the guide surface 23a) are guided.

The position of the cam lever 30 in the radial direction of the rotary cam 20 depends on the accumulation amount of the sheets P set on the hopper 6 as described above, and therefore the cam lever 30 has a fan-shaped guide surface. 23e, the guide slope 24b (after that, the fan-shaped guide surfaces 23b to 23d),
Which of the guide slopes 24c (then, the guide surface 23a) is guided depends on the amount of the sheet P accumulated. Therefore, for example, when the accumulation amount of the paper P is minimum, the cam lever 30 is guided to the fan-shaped guide surface 23e, and the paper P is
In the case where the accumulation amount of is the maximum, it is guided to the guide slope 24c (then, the guide surface 23a).

Next, when the rotary cam 20 further rotates, the cam lever 30 moves to the outer peripheral side from any of the guided guide surface 23a and the fan-shaped guide surfaces 23b to 23e, that is, from the radial position of the rotary cam 20 at that time. Riding on the outer peripheral surface of the first fan-shaped cam (fan-shaped cams 22a to 22e). That is, the cam lever 30 makes a small displacement operation in the radial direction of the rotary cam 20 (the direction from the rotation center of the rotary cam 20 toward the outer periphery), and the cam lever holder 35 makes a small rotation in the clockwise direction in FIG. 13 (A). Therefore, this causes the hopper 6 to slightly swing in the direction away from the sheet feeding roller 3. As described above, the paper P that is in pressure contact with the paper feed roller 3 is in a state in which the uppermost paper P is slightly separated from the paper feed roller 3 (free state).

The above is the rotary cam 20 and the cam lever 3.
0, and the outline of the engagement operation of the cam lever holder 35. From the above, the hopper release means rotates the hopper 6 so as to move the hopper 6 away from the paper feed roller 3 most (a large release mode) (the cam lever 30 is the outermost peripheral side). (The state in which it engages with the outer peripheral surface of the fan-shaped cam 22a located at), and the "non-release mode" in which the hopper 6 is pressed against the sheet feeding roller 3 (the cam lever 30 is the non-cam portion 26 (area) or the cam lever guide portion (area)). State) and a "small release mode" in which the hopper 6 is rotated and held so that the uppermost sheet P and the sheet feeding roller 3 are slightly separated from each other (the cam lever 30 moves from one region to another region). And a rotary cam 20 (feeding roller shaft 3).
These can be freely executed by the rotation control of a).

The number of steps of the stepped cam portions (fan-shaped cams 22a to 22e) formed on the rotary cam 20 is five in this embodiment, but as is clear from the above, the number of steps is finer. Needless to say, it is possible to control the hopper 6 according to the amount of accumulated paper P.

Next, referring to FIGS. 14 to 22,
The operation and effect of the hopper release means will be described while describing the actual paper feed control in the paper feed unit 1. Here, FIG. 14 shows the paper feed roller 3, the cam lever 30,
It is a timing chart showing the operation transition of the hopper 6,
15 to 22 show the paper feed roller 3 and the cam lever 3 at each timing of the timing chart shown in FIG.
0 is a state explanatory view showing the state of the hopper 6, and FIG.
(B) is mainly the cam lever 30 and the rotary cam 20.
It shows the engagement state with.

The areas shown in FIG. 14 are the areas shown in FIG.
It corresponds to each area of the rotary cam 20 shown in FIG. Further, the reference numerals shown on the chart of the cam lever 30 are fan-shaped cams 22a to 22e with which the cam lever 30 is engaged.
Alternatively, the guide surface 23a and the fan-shaped guide surface (23b-23
e) is shown. Further, the "non-release" of the hopper 6 means the hopper 6 in a state where the paper P set on the hopper 6 in the non-release mode is in pressure contact with the paper feed roller 3, and the "small release" is the same. The sheet P (the uppermost sheet P) set on the hopper 6 in the small release mode means the hopper 6 in a state slightly separated from the sheet feeding roller 3, and the "large release" means the large release. This means the hopper 6 in the state where the hopper 6 is farthest from the paper feed roller 3 in the release mode. The forward rotation of the paper feed roller 3 means the clockwise rotation in FIGS. 15 to 22, and the normal rotation of the paper feed roller 3 causes the rotary cam 20 to rotate counterclockwise in FIG. Become.

First, at the start of feeding, the cam lever 30 is on the fan-shaped cam 22a (FIG. 15 (B)), and the hopper 6 is in the most separated state from the paper feed roller 3 (FIG. 15).
(A)), the paper feeding unit 1 is in a resting state in which the paper P can be set in this state. When the paper feed roller 3 is rotated in the normal direction from this state for the paper feed operation, the rotary cam 20 rotates counterclockwise in the figure, whereby the cam lever 30 is disengaged from the fan-shaped cam 22a and the area of the non-cam portion 26 (area). ) (FIG. 16 (B)), and the paper P set on the hopper 6 is pressed against the paper feed roller 3 (FIG. 16).
(A)). That is, the hopper release means executes the non-release mode (FIG. 14-section a). Then, the rotation of the paper feed roller 3 starts the feeding of the uppermost sheet P.

Next, when the paper feed roller 3 further rotates in the forward direction, the cam lever 30 starts to engage with the guide slope 24a (cam lever guide portion: area), and the accumulated amount of the paper P set on the hopper 6 is reached. Accordingly, the guide surface 23a and the fan-shaped guide surfaces 23b to 23d are guided (see FIG. 17).
(B): In this embodiment, the fan-shaped guide surface 23c is guided via the guide slope 24b). At this time, the paper P set on the hopper 6 remains in pressure contact with the paper feed roller 3 (non-release state) (FIG. 14-section b,
c).

Next, when the paper feed roller 3 further rotates in the forward direction, the cam lever 30 moves from the fan-shaped guide surface 23c to the fan-shaped cam 22c.
18 (B), and the hopper 6 makes a small turn in a direction away from the sheet feeding roller 3 (see FIG. 18B).
(A)), so that the paper P is slightly separated from the paper feed roller 3 (FIGS. 19A and 19B). That is, the hopper release means executes the small release mode (FIG. 14).
-Section d).

Then, the feed roller 3 makes one rotation (360 °).
However, the flat portion in the substantially D-shape in side view has the separation pad 8
The rotation of the paper feed roller 3 is stopped in a state where the sheet P is opposed to the sheet P, and the sheet P undergoing the printing operation (conveyance operation) is placed in a state in which the sheet is not loaded, and in this state, the sheet P waits until the feeding of the next sheet P starts. (FIGS. 19A and 19B) (FIG. 14-section e). In other words, the hopper release means sets the hopper 6 to the farthest state from the paper feed roller 3 after the completion of the paper feed operation for one paper P when the feeding job for the second and subsequent paper P remains. The large release mode is not executed, and the small release mode is executed after the paper feed operation of the paper P is completed, so that the uppermost paper P is slightly separated from the paper feed roller 3. Then, at the time of feeding the next paper P, the hopper 6 can press the paper P against the paper feed roller 3 with a slight swing angle.

Next, when all the printing operations have been completed and there is no subsequent feeding job of the paper P, the hopper release means executes the large release mode and shifts to the idle state. More specifically, after the end of section e in FIG. 14 (after the end of the printing operation)
To f section. In the section f, the feed lever 3 is rotated in the forward direction so that the cam lever 30 moves to the fan-shaped cam 22.
Remove it from c and invite it to the non-cam part 26 (Fig. 20).
(B)), and by reversely rotating the paper feed roller 3 from this state, the cam lever 30 is guided to the outer peripheral surface of the fan-shaped cam 22a (FIG. 21B), and the hopper 6 is moved to the paper feed roller 3
It is rotated so that it is most distant from, that is, the large release mode is executed (FIG. 22).

In this case, the cam lever 30 is temporarily removed from the fan-shaped cam 22c by turning the paper feed roller 3 forward, and the cam lever 30 is guided to the non-cam portion 26. However, the paper feed roller 3 is rotated in the reverse direction (rotary cam). 20 can also be guided to the non-cam portion 26 by rotating it in the clockwise direction in the figure. In this case, the cam lever 30 moves the fan-shaped cam 22c.
It is possible to execute the large release mode by rotating the paper feed roller 3 once in the reverse direction from the state shown in FIG.

As described above, the hopper release means uses the small release mode when the feeding job for feeding the second and subsequent papers P remains after the completion of the feeding operation of the uppermost paper P. The next paper P
It is possible to minimize the swing range (swing angle) of the hopper 6 when feeding the hopper 6, thereby reducing noise generated when the hopper 6 swings, and performing high-speed sheet feeding operation (repeating operation). Paper feeding) can be executed.

Although the hopper 6 is rotated by the compression coil spring 7 in the direction in which the hopper 6 is in pressure contact with the sheet feeding roller 3, the rotation in the pressure contact direction is performed by the release bar 16 in a state of being restrained by the cam lever holder 35. Therefore, the paper P accumulated on the hopper 6 is compressed by the compression coil spring 7.
The spring force does not forcefully collide with the paper feed roller 3, which makes it possible to prevent the unevenness of the paper P and the occurrence of defects such as wrinkles on the paper P.

By the way, returning to FIG. 7, the tip of the paper P accumulated on the hopper 6 slides on the guide surface 13a of the guide member 13 when the hopper 6 swings. If the coefficient of friction with the tip is large, a smooth paper feeding operation cannot be performed even if the swing range (swing angle) of the hopper 6 is suppressed as described above. Therefore, the guide surface 13a in the present embodiment keeps the friction coefficient low by applying the lubricant as described above (in the present embodiment, μ
<0.3), which ensures a smooth paper feeding operation. However, here, in a series of paper feeding operations, by performing the following control, it becomes possible to cover the trouble at the time of paper feeding operation and ensure the normal print quality more reliably.

First, in FIG. 7, the paper P fed by the paper feed roller 3 is the detector 136 of the paper detector 136.
After passing a, it is nipped by the transport driving roller 162 and the transport driven roller 163. Then, after being nipped by the two rollers, a certain amount of cueing control is performed and printing on the paper P is started. Here, the fixed amount of cueing control is performed by receiving a passage detection signal of the leading edge of the sheet P from the sheet detector 136 and rotationally driving the transport driving roller 162 by a predetermined phase at the timing. There are cases.

On the other hand, in FIG. 14, the timing at which the paper detector 136 detects the passage of the leading edge of the paper P, the timing at which the leading edge of the paper P reaches the nip point between the transport driving roller 162 and the transport driven roller 163, and the hopper 6 Shows the relationship with the state of. That is, the leading edge of the paper P passes through the detector 136a of the paper detector 136 at the point indicated by the code I, and the code II
At the point indicated by, the nip point between the transport driving roller 162 and the transport driven roller 163 is reached.

However, as described above, if the swinging movement of the hopper 6 is not smoothly performed and the timing at which the uppermost sheet P is brought into pressure contact with the sheet feeding roller 3 is delayed, the above-mentioned points I and II are changed to those in FIG. As shown in, there is a risk of shifting to points I'and II '. Then, between the point I'and the point II ', there is a possibility that the point where the hopper 6 switches from the non-release state to the small release state is included, that is, the small release mode may be executed.

When the hopper 6 executes the small release mode, the cam lever 30 moves the small diameter cam portion 23 as described above.
Since it rides on the large-diameter cam portion 22, a rotational load is applied to the paper feed roller shaft 3a, which is the rotating shaft of the rotary cam 20, at this time, and the paper feed roller shaft 3a is twisted. When the paper feed roller shaft 3a is twisted in this way, the amount of paper P fed is reduced accordingly.

However, as described above, the transport driving roller 162 is used.
In the case where the amount of the paper P that has been cued from the nip point between the transport driven roller 163 and the conveyance driven roller 163 is controlled by the timing when the passage detection signal from the paper detector 136 at the leading end of the paper P is received, the uppermost paper P is fed. When the timing of press contact with the paper roller 3 is delayed, and thus the feed amount of the paper P decreases due to the twist of the paper feed roller shaft 3a between the points I'and II 'as described above, the leading end of the paper P is driven to be conveyed. The timing of reaching the nip point between the roller 162 and the transport driven roller 163 may be delayed, and the desired cue amount may not be obtained. This is because the hopper 6 is in the large release state (the paper feeding unit 1 is in the rest state), and the non-release mode is executed from the large release state, so that the uppermost sheet P is discharged.
This is a particular problem because the oscillating angle of the hopper 6 is maximized in the first first sheet P when the series of paused jobs is started.

Therefore, only the first first sheet at the start of a series of sheet feeding jobs, for example, the so-called bite-out type skew removal (after the leading edge of the sheet P has been eaten by the transport driving roller 162 and the transport driven roller 163, It is possible to solve the above-described problem of insufficient cueing by performing a method of removing the skew by discharging the gas to the upstream side. It should be noted that the biasing force of the biasing means of the hopper 6 (the compression coil spring 7 in this embodiment) should be strong so that the hopper 6 can rotate more reliably in the direction in which it comes into pressure contact with the sheet feeding roller 3. Also, the same effect can be obtained.

[0113]

As described above, according to the present invention, the point of action of the force applied by the biasing means to the hopper and the point of action of the force applied by the hopper release means to the hopper are viewed in plan view. Since the hoppers are arranged at substantially the same position, almost no bending moment is generated in the hopper, which prevents the hopper from being bent, thereby maintaining a normal sheet feeding operation.

[Brief description of drawings]

FIG. 1 is an external perspective view of an apparatus main body of an inkjet printer according to the present invention.

FIG. 2 is an exploded perspective view of the apparatus body of the inkjet printer according to the present invention.

FIG. 3 is a side sectional view of the inkjet printer according to the present invention.

FIG. 4 is a front view of the apparatus main body of the inkjet printer according to the present invention.

FIG. 5 is a perspective view of a sheet feeding device according to the present invention.

FIG. 6 is a front view of the sheet feeding device according to the present invention.

FIG. 7 is a side sectional view of the sheet feeding device according to the present invention.

FIG. 8A is a side view of a paper feed roller and a paper feed auxiliary roller, and FIG. 8B is a front view of the same.

9 is an explanatory view (partially enlarged view of FIG. 7) of a plunging angle of the paper P into the separation pad 8. FIG.

FIG. 10 is a perspective view (partially enlarged view) of the sheet feeding device according to the present invention.

FIG. 11 is a schematic diagram showing an operating position of an external force acting on the hopper 6.

FIG. 12 (A) is a front view of a rotary cam,
(B) is a yy sectional view in (A).

FIG. 13A is a front view of a cam lever holder,
(B) is the same side view.

FIG. 14 is a timing chart showing changes in the operation of the paper feed roller, cam lever, and hopper.

15A and 15B are state explanatory views of the sheet feeding device according to the present invention during a sheet feeding operation, in which FIG. 15A shows a positional relationship between a sheet feeding roller and a hopper, and FIG. 15B shows engagement between a cam lever and a rotary cam. It shows the state.

16A and 16B are state explanatory views of the sheet feeding device according to the present invention during a sheet feeding operation, in which FIG. 16A shows a positional relationship between a sheet feeding roller and a hopper, and FIG. 16B shows engagement between a cam lever and a rotary cam. It shows the state.

17A and 17B are state explanatory views of the sheet feeding device according to the present invention during a sheet feeding operation. FIG. 17A is a positional relationship between the sheet feeding roller and the hopper, and FIG. 17B is an engagement between a cam lever and a rotary cam. It shows the state.

18A and 18B are state explanatory views of the sheet feeding device according to the present invention during a sheet feeding operation; FIG. 18A is a positional relationship between a sheet feeding roller and a hopper, and FIG. 18B is an engagement between a cam lever and a rotary cam. It shows the state.

19A and 19B are state explanatory views of the sheet feeding device according to the present invention during a sheet feeding operation; FIG. 19A is a positional relationship between a sheet feeding roller and a hopper; and FIG. 19B is an engagement between a cam lever and a rotary cam. It shows the state.

20A and 20B are state explanatory views of the sheet feeding device according to the present invention during a sheet feeding operation; FIG. 20A shows a positional relationship between a sheet feeding roller and a hopper; and FIG. 20B shows engagement between a cam lever and a rotary cam. It shows the state.

21A and 21B are state explanatory views of the sheet feeding device according to the present invention during a sheet feeding operation. FIG. 21A is a positional relationship between a sheet feeding roller and a hopper, and FIG. 21B is an engagement between a cam lever and a rotary cam. It shows the state.

22A and 22B are state explanatory views of the sheet feeding device according to the present invention during a sheet feeding operation, in which FIG. 22A shows the positional relationship between the sheet feeding roller and the hopper, and FIG. 22B shows the engagement between the cam lever and the rotary cam. It shows the state.

FIG. 23 is an external perspective view of a sheet feeding device according to the related art.

FIG. 24A is a side sectional view of a sheet feeding device according to a conventional technique, and FIG. 24B is an explanatory diagram showing a point of action of an external force applied to a hopper.

[Explanation of symbols]

1 Paper feeding unit 2 Paper feeding unit frame 3 paper feed rollers 6 hoppers 8 separation pads 13 Guide member 15 Paper feed auxiliary roller 16 Release Bar 20 rotary cam 21 rotation axis 22a-22e fan-shaped cam 23a Guide surface 23b-23e Fan-shaped guide surface 24a-24c Guide slope 26 Non-cam part 30 cam lever 35 Cam lever holder 120 carriage unit 160 transport unit 180 ink system unit 100 inkjet printer P printing paper

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Toru Fukushima             Seiko, 3-3-3 Yamato, Suwa City, Nagano Prefecture             -In Epson Corporation (72) Inventor Masashi Furuyama             Seiko, 3-3-3 Yamato, Suwa City, Nagano Prefecture             -In Epson Corporation F term (reference) 3F343 FA01 FB02 FB04 GA02 GB01                       GC01 GD01 HD09 HD10 HD17                       KB03 KB05 LA04 LA15 LB08                       LC11 LC12 LD25 LD26

Claims (5)

[Claims] 1. A paper feed roller that feeds a recording material to a downstream side by rotating, and a plate-like member that is long in the width direction of the recording material, and an upstream side from a pressure contact with the paper feeding roller And a hopper which is provided with a rotation fulcrum and which separates and presses the paper feed roller by being rotated, and the hopper which is arranged at a position facing the paper feed roller with the hopper sandwiched therebetween. A plurality of sheets provided with an urging means for urging the back side of the hopper toward the paper feeding roller and a hopper releasing means for separating the hopper from the paper feeding roller against the urging means. A sheet feeding device for depositing and holding the recording material in an inclined posture and pushing up the recording material deposited and held by the hopper, one by one from the uppermost recording material to the downstream side, Of the force that the biasing means applies to the hopper And use point, the sheet feeding apparatus in which the hopper release device has a working point of the force to be applied to said hopper, characterized in that arranged substantially at the same position in a plan view of the hopper. 2. The paper feed roller according to claim 1,
A sheet feeding device, wherein one of the rotation shafts of the sheet feeding roller is provided at a position deviated to the axial end side. 3. The hopper release means according to claim 1 or 2, wherein the hopper release means has a first shaft portion extending in the longitudinal direction of the hopper above the urging means, and the hopper release means from one end of the first shaft portion. A second shaft portion whose front end extending vertically to the vicinity of the biasing means engages with an engaging portion provided on the back side of the hopper, and the other end of the first shaft portion to the second shaft portion. A release bar having a third shaft portion extending in parallel and having a substantially U-shape in a plan view, a bearing portion pivotally supporting the first shaft portion, and operating the third shaft portion. Accordingly, the release device is configured to rotate the second shaft portion in a direction in which the second shaft portion is separated from the paper feed roller about the first shaft portion as a rotation shaft. 4. The paper feeding device according to claim 3, wherein the drive source of the release bar rotating means is also used as the drive source of the paper feeding roller. 5. A recording apparatus, comprising: a recording section for recording on a recording material; and a discharge section for discharging the recording material recorded by the recording section, the recording apparatus comprising: A recording apparatus comprising the sheet feeding device according to any one of 4 above.