JP2938681B2 - Automatic feeding device and image forming device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic feeding apparatus for automatically feeding recording sheets one by one.

[0002]

[Prior art]

<Prior art 1> Conventionally, recording apparatuses such as printers, copiers, and facsimile machines use a recording sheet such as paper or a plastic thin plate by driving an energy generator of a recording head based on image information transferred. It is configured to record an image consisting of a dot pattern on top. The recording apparatus can be classified into an ink jet system, a wire dot system, a thermal system, an electrophotographic system, and the like according to the recording system.

[0003] In addition to plain paper, recording sheets used in recording apparatuses include cardboard such as postcards and envelopes, and special sheets such as plastic thin plates. The supply of the recording sheet is 1
In addition to manual sheet insertion, automatic and continuous feeding is performed by an automatic feeding device.

In general, the paper feed mechanism in the automatic feeding apparatus is configured such that one paper feed roller is disposed on each of the left and right sides of a recording sheet, and furthermore, separation pawls for pressing both front sides of the recording sheet in the paper feeding direction are provided. It has a pressing mechanism for arranging the recording sheets one by one and pressing the recording sheets against the respective sheet feeding rollers, so that the recording sheets are separated and supplied one by one. However, today, due to demands for cost reduction and downsizing due to simplification of components, a single-claw separation type configuration in which the separation claw is arranged on only one side has come to be used.

FIG. 16 is a perspective view of an automatic feeding mechanism using the one-claw separation method. In the figure, 101,
A paper feed roller 102 is fixed on a paper feed roller shaft 106 and is configured to rotate by receiving a driving force from a drive gear 107. A paper edge guide 103 regulates the paper edge of the set recording sheet 110 opposite to the separation claw 104. Reference numeral 105 denotes a pressure plate, which is a set recording sheet 11
0 is pressed against the paper feed rollers 101 and 102. A separation pad 108 prevents double feed near the last paper. A frame 109 for holding these components also serves as a guide for the recording sheet 110 after feeding.

In the above-described configuration, the driving force of the recording sheet conveying system of the recording apparatus is transmitted to the driving gear 107, and the recording sheets 11 are driven by driving the paper feed rollers 101 and 102.
0 is separated and fed one by one. The reason why two paper feed rollers are provided for the separation claw is that the recording sheet can be stably fed even if the size of the recording sheet in the width direction is different. <Prior Art 2> Recording sheets used in recording apparatuses include plain paper, cardboard such as postcards and envelopes, and special sheets such as plastic thin plates. The supply of the recording sheet is 1
In addition to manual sheet insertion, automatic and continuous feeding is performed by an automatic feeding device.

[0007] Further, there is a mechanism shown in FIG. 23 for the purpose of preventing a phenomenon that a corner at the tip of a part of the recording sheet does not catch on the separation claw when the recording sheet is stacked on the stacking means. The sheet P on the stacking plate 21 is pressed against the roller 123 of the feeding roller 120 by the elastic force of the pressure spring 72. The feeding roller 120 includes a half-moon roller 122 fixed to a shaft 121 and the roller 123. 127
Denotes a separation claw, and 136 denotes a guide member for guiding the recording sheet to the separation claw.

[0008]

[Problems to be solved by the invention]

<Problem of the First Invention> In the above-described conventional example, since the separation claw is provided only on one side with respect to the sheet feeding roller, resistance at the time of separation is generated only on one side.
Significant drawbacks such as skew and paper jam have occurred. Therefore, a configuration has been proposed in which the conveyance force of the paper feed roller on the separation claw side is increased (changing the pressure, changing the friction coefficient of the paper feed roller, and the like). In this case, the delay cannot be eliminated, and the occurrence of the skewing, paper feed jam, and the like as described above cannot be suppressed.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an automatic feeding apparatus capable of separating a recording sheet by a one-claw separation method without causing the recording sheet to be skewed or jammed. <Problem of the Second Invention> In the above-mentioned conventional example of <Prior Art 2>, the guide member 136 is fixed to the automatic feeding device.

Since the separation claw usually regulates both corners of the leading end of the recording sheet, when the recording sheet is separated, both corners of the recording sheet receive the same degree of resistance, so that the recording sheet is not obliquely fed. There was no problem. However, in recent years, for the purpose of cost reduction and simplification of the mechanism, there has been a demand for an automatic feeding apparatus of a system in which the regulation of one end angle of the recording sheet (separation claw) is removed. In this method, since there is only one separation claw, if the resistance of the separation claw is large, the recording sheet corner is not separated from the separation claw, and the corner at the side without the separation claw is fed to the oblique feeding. There was a problem of sending.

For this reason, if a guide for guiding the recording sheet to the separation claw is provided in a state fixed to the automatic feeding device as in the related art, the tip corner generated when the leading end of the recording sheet separates from the separation claw is provided. Since the guide member comes into contact with the deflection near the recording sheet, the deflection at the corner of the leading end of the recording sheet cannot be sufficiently separated, the separation resistance increases, and the oblique feeding occurs. Was.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an automatic feeding apparatus in which a recording sheet can be guided to a separation claw without hindering a feeding operation of the recording sheet.

[0013]

<Means for Solving the Problems><Means of the First Invention> The present invention relates to an automatic feeding apparatus for separating and feeding recording sheets stacked on a stacking unit one by one. A plurality of coaxially provided rotary feeders having a circular arc portion that feeds out a sheet and abuts on the recording sheet, and a portion that does not abut on the recording sheet, and a recording sheet loaded on the loading means. And separating means for separating the recording sheets sent by the rotary feeder one by one, provided at one side corner of the front end in the paper feeding direction. The phase of the side where the arc portion of the rotary feeder that contacts the recording sheet is shifted so that the arc portion of the rotary feeder closer to the rotary feeder contacts the recording sheet earlier than the arc portions of the other rotary feeders. It is a feature. According to the present invention, there is provided an automatic feeding device for separating and feeding recording sheets stacked on a stacking unit one by one, wherein a plurality of coaxial rotary feeders for feeding the recording sheets from the stacking unit are provided. And a recording sheet, which is disposed at one side corner of the front end of the recording sheets stacked in the stacking direction in the sheet feeding direction and is fed by the rotary feeder,
Separating means for separating sheets one by one, provided in the loading means,
A pressure plate loaded with the recording sheet and urged toward the rotary feeder, and rotated together with the rotary feeder so as to press the pressure plate while contacting the recording sheet with the rotary feeder. And cam portions provided at both ends of the rotary shaft of the rotary feeder for releasing the pressing, and the rotary feeder closer to the separating unit among the plurality of rotary feeders is provided. The phase of the cam portion is shifted so that the cam portion comes into contact with the recording sheet prior to the other rotary feeding members.

<Means of the Second Invention> According to the present invention, there is provided a stacking unit capable of stacking recording sheets, a rotary feeder provided for sending out the recording sheets from the stacking unit, and a stacking unit mounted on the stacking unit. And a separating claw that separates the recording sheets one by one during feeding by the rotary feeder by regulating an end portion of the recording sheet that is being stacked. Guide the corners of the recording sheet tip supplied to the means inside the separation claw,
A guide member that separates from the recording sheet during separation is provided.

[0015]

<Operation><Operation of the First Invention> The recording sheet stacked on the stacking means has a plurality of arc-shaped portions which come into contact with the recording sheet and portions which do not come into contact with the recording sheet and which are provided coaxially. After being sent out by the rotary feeder, the recording sheet stacked on the stacking means is separated by one by a separating means arranged at one side corner of the front end in the sheet feeding direction.
Separated one by one. At the time of this separation, the phases of the arc portions of the plurality of rotary feeders that are in contact with the recording sheet are shifted from each other. The recording sheet comes out of contact with the recording sheet before the arc portion of the feeder. Further, the recording sheets stacked on the stacking means are sent out by a plurality of rotary feeders provided coaxially, and then arranged at one side corner of the front end in the sheet feeding direction of the recording sheets stacked on the stacking means. The sheets are separated one by one by the provided separating means. And
At the time of this separation, provided at both ends of the rotating shaft of the rotary feeder,
While the recording sheet is loaded and the pressure plate urged toward the rotary feeder is pressed, the cam portion that rotates together with the rotary feeder and releases the pressing is out of phase, so that it is close to the separating unit. The rotary feeder on the side comes into contact with the recording sheet prior to the other rotary feeders and feeds out the recording sheet. On the separation claw side of the recording sheet, the formation of the loop is delayed due to the resistance from the separation claw, but since the contact portion of the rotary feeder on the separation claw side comes into contact with the recording sheet first to give a feeding action,
The delay is eliminated. As a result, the recording sheets can be properly separated and fed without skewing or jamming.

<Operation of the Second Invention> When the rotary feeder is not fed, the guide member (guide means) is located near the separation claw, so that the corners of the recording sheet supplied to the stacking means can be removed. Guide inside the separation claw. When feeding the recording sheet, the guide member moves in a direction away from the separation claw. Accordingly, the guide member guides the recording sheet to the separation claw, and does not obstruct the feeding of the recording sheet by separating from the loop at the time of feeding the recording sheet.

[0017]

【Example】

<First Embodiment of First Invention> FIGS. 1 to 11 show a first embodiment of the present invention.
An example will be described. The present embodiment is a recording apparatus integrated with an automatic paper feeder, and includes a paper feed unit, a paper feed unit, a paper discharge unit, a carriage unit,
It is composed of a cleaning unit. First, the general configuration and operation of these will be described.

FIG. 1 is a perspective view of the overall configuration, FIG. 2 is a front view of the paper feeding unit, and FIG. 3 is a side view of the paper feeding unit.

The paper feeding section 11 is attached to the main body at an angle of 30 ° to 60 °, and the set recording sheet P is discharged horizontally after printing. The paper feed unit 11 includes a paper feed roller 5, a separation claw 17, a movable side guide 19, a base 20, a pressure plate 21, a pressure plate spring 22, drive gears 25 to 30, a release cam 31, a claw spring 32, a release lever 33, and a release cam. 35 mag. Normally, since the release cam 31 pushes the pressure plate 21 down to the position shown in FIG.

With the recording sheet P set, the drive of the transport roller 36 is transmitted to the paper feed roller 5 and the release cam 31 by the gears 25-30. Release cam 31
Is separated from the pressure plate 21, the pressure plate 21 rises to the position shown in FIG. 6, the sheet feed roller 5 and the recording sheet P come into contact with each other, are picked up by the rotation of the sheet feed roller 5, and are separated one by one by the separation claw 17. . The separated recording sheet P is sent to a paper feeding unit. The paper feed roller 5 and the release cam 31 make one rotation until the recording sheet P is sent to the paper feed unit 11, and the drive from the paper feed roller 5 is stopped with the pressure plate 21 released to the paper feed roller 5 again, This initial state is maintained.

The paper feeding section 12 includes a transport roller 36, a pinch roller 37, a pinch roller guide 39, a pinch roller spring 40, a PE sensor lever 41, a PE sensor 42, a PE sensor spring 43, an upper guide 45, a platen 46, and the like. The recording sheet P sent to the paper feeding unit 12 is a platen 4
With the guide 6, pinch roller guide 39, and upper guide 45 as guides, the sheet is fed to a roller pair of a transport roller 36 and a pinch roller 37. A PE sensor lever 41 is provided in front of the roller pair, detects the leading end of the recording sheet P, and obtains a printing position on the recording sheet P. Pinch roller 37
By pressing the pinch color guide 39 with a pinch roller spring 40, the pinch roller guide 39 is pressed against the conveying roller 36 to generate a conveying force of the recording sheet P. The roller pair 3
The recording sheet P sent by the LF motor 47
As a result, the pair of rollers 36 and 37 is rotated to advance along the platen 46, and the recording head 49 can perform recording based on predetermined image information. The recording head 49 is formed integrally with the ink tank and is an easily replaceable inkjet recording head. The recording head 49 is provided with an electric exchanger, and performs recording by discharging ink from the discharge ports using a pressure change generated by growth and shrinkage of bubbles caused by film boiling caused by applied thermal energy.

The carriage section 15 includes a carriage 50 on which a recording head 49 is mounted, a carriage 50, and a recording sheet P.
A guide shaft 51 for reciprocating scanning in a direction perpendicular to the conveying direction of the carriage 50 and a guide 52 for holding the rear end of the carriage 50 and maintaining a space between the head and the paper, and a timing belt 55 for transmitting the drive of the carriage motor 53 to the carriage 50 An idle pulley 56 on which a timing belt 55 is stretched, a flexible substrate 57 for transmitting a head drive signal from an electric substrate to the recording head 49, and the like. An image is formed on the recording sheet P conveyed on the platen 46 by being scanned integrally with the recording head 49 and the carriage 50.

The paper discharge section includes a paper discharge roller 59 and a paper discharge roller 5.
9, a transmission roller 60 for transmitting the drive of the transport roller 36, a spur 61 for assisting discharge, and a discharge tray 62 are provided. The image on the recording sheet P is discharged onto the paper discharge tray 62 by the paper discharge roller 59 and the spur 61 without soiling the image on the recording sheet P.

The cleaning section 16 includes a pump 63 for cleaning the recording head 49, a cap 65 for suppressing the drying of the recording head 49, and a drive switching arm 66 for switching the driving from the transport roller 36 to the sheet feeding section 11 and the pump 63. It is composed of Since the drive switching arm 66 is at the position shown in FIG. 1 except when feeding and cleaning, and a planetary gear (not shown) that rotates around the axis of the transport roller 36 is fixed at a predetermined position, The drive of the roller 36 is not transmitted to the pump 63 and the paper feed unit 11. By moving the carriage 50, when the drive switching arm 66 is moved in the direction of arrow A, the planetary gears move in accordance with the normal rotation and reverse rotation of the transport roller 36, and when the transport roller 36 rotates forward, the drive to the paper feed unit is performed. The drive is transmitted to the pump 63 at the time of reverse rotation.

As the LF motor 47 for driving the transport rollers 36 and the carriage motor 53 for driving the carriage 50, a stepping motor that rotates by a predetermined angle in accordance with a signal sent from a driver (not shown) is used. .

The paper feed roller 5 is provided with a sensor plate 69 having a radius smaller than the diameter of the paper feed roller rubber 67 attached to the paper feed roller 5. The sensor plate 69 is partially cut out, and the sheet feed roller 5 and the release cam 3
Only when the plate 1 is at the initial position for releasing the pressure plate 21 shown in FIG. 5, the roller sensor 72 composed of a photo interrupter or the like provided directly on the electric board 70 is configured to be in a light-transmitting state without blocking light. . By detecting the state of the sensor plate 69, the release cam 3, which is synchronized with the angular position of the paper feed roller 5 and the phase of the paper feed roller 5, is linked.
1 can be detected, and the timing of control in the sheet feeding sequence of the recording sheet P can be measured.

Next, details of the main components of the paper feed unit 11 will be described.

The paper feed unit 11 is formed by attaching each component of the paper feed unit to the base 20. In the present embodiment, the sheet feeding unit 11 is based on one side of the recording sheet P, and the inside of the right side plate of the base 20 is based on paper.
As shown in FIG. 5, the base 20 has a concave portion for providing the pressure plate spring 72 at a position where the pressure plate 21 can be retracted as shown in FIG. 5 and substantially opposed to the roller portion 5 c of the paper feed roller 5. Pressure plate 2
Numeral 1 is connected to the base 20 by a pressure plate shaft 21b at the upper end on both ends, and is rotatable about the pressure plate shaft 21b. A separation pad 73 made of a material having a relatively large friction coefficient such as artificial leather is provided at the position of the paper feed roller of the pressure plate 21 to prevent double feed when the number of sheets is reduced. A movable side guide 19 that can slide left and right on the pressure plate 21 is attached so that recording sheets P of different sizes can be set on the paper reference surface.

The paper feed roller 5 is rotatable with both ends held by a base 20. The feed roller 5 has a shaft 5b.
And a roller portion 5c, and is integrally formed of plastic or the like. A paper feed roller rubber 67 for transporting the recording sheet P around the roller portion 5c is provided. The roller portion 5c is formed in a D-shape (or a half-moon portion), and a roller roller 75 having a radius smaller by 0.5 to 3 mm than the radius of the paper feed roller rubber 67 attached to the paper feed roller 5 on each outer side of the roller portion 5c. Is provided, and when the recording sheet P touches the roller rubber 67 of the paper feed roller 5 except when the paper is fed, the contamination of the image or the positional deviation of the paper feed roller 5 is prevented.

Two rollers 5c are provided, and are fixed at positions of about 40 mm and about 170 mm from the paper reference, respectively. Therefore, the A4 size or the like has two roller portions 1
c, and postcards and the like are conveyed by one roller on the paper reference side.

Here, the roller portion 5c provided on the separation claw 17 side has a sectional shape as shown in FIG. The roller portion 5c of the separation claw 17 abuts on the recording sheet P in the paper feeding direction A (arrow in the drawing) by a degree ahead of the roller portion 5c located on the opposite side to the separation claw 17 side. The phases are shifted so that they touch.

Therefore, when the sheet P is separated and fed, the separation claw 17 side of the sheet P starts to move first, and the recording sheet P forms a loop at the separation claw 17 due to the resistance of the separation claw 17 to be separated one by one. However, at this time, the delay due to the resistance is eliminated by moving earlier, and the recording sheet P is separated and fed without skewing.

The value of the angle a ° differs depending on the outer diameter of the roller. In this embodiment, the outer diameter of φ24 is 0.5 °
There is no problem up to about 5 °.

The drive switching arm 66 of the cleaning section 16 is moved by the carriage 50 in the direction of arrow A.
When the transport roller 36 is rotated forward, a planetary gear (not shown) moves and meshes with the input gear 25 to transmit drive to the paper feeding unit. The input gear 25 transmits drive to a paper feed roller gear 28 connected to the paper feed roller 5 via idler gears 26 and 27, and can convey the recording sheet P by rotating the paper feed roller 5. Further, the drive of the paper feed roller gear 28 is transmitted to a release cam 31 via a clutch gear 29 and an idler gear 30. At this time, the feed roller 5 and the release cam 31 are configured to be in phase with each other for each rotation, and when the pressure plate 21 shown in FIGS. As shown in the figure, the half-moon portion is arranged at a position facing the pressure plate 21. The release cam 31 is shaped so as to release the pressure plate 21 only during the angle of about 120 ° of the half-moon portion of the paper feed roller 5.
When the recording sheet P or the pressure plates 21 and 2
It is configured to be in contact with a pressure of 00 g to 500 g. Further, the release cam 31 releases the pressure plate 21 by pressing down the press-down portion 21 c of the pressure plate 21 protruding from a hole opened in the right side plate of the base 20. At this time, the cam 21d on the side closer to the press-down portion 21c of the press plate 21 presses down the press plate cam 76 attached to the base 20, and the press plate cam 76 rotates about the center 76b. Then, the pressure plate cam 76 pulls down the cam 5f outside the left paper feed roller portion 5c. As described above, the depressed portion 2 at the end of the pressure plate 21
Even if the pressure plate 1c is lowered, the pressure plate 21 does not tilt with respect to the base 20 and is released substantially in parallel. A clutch spring 77 is provided in the middle of the clutch gear 29, as indicated by an arrow B in FIG.
In the direction, the spring is configured to be tightened so that it does not reverse. Thus, when performing registration or the like, the paper feed roller 5 does not rotate due to the elasticity of the recording sheet P or the like, so that good registration can be performed.

The separation claw 17 is rotatable about a center 17b.
To 20 g to 100 g. The separation claw 17
The separation is performed at the time of feeding a so-called plain paper recording sheet P, and is provided only on the paper reference side as shown in FIG. 2. I have. The recording sheets P can be separated one by one by receiving resistance at the triangular portion. Also,
For separation of thick paper or the like other than plain paper, the separation claw 17 is abutted against the lower guide portion 20b of the base 20 without being applied to the recording sheet P, so that the sheet can be separated one by one using the resistance of the lower guide portion. .

The release lever 33 and the release cam 35
It is provided coaxially with the release cam 31. The release lever 33 and the release cam 35 are not interlocked with the release cam 31 and are independent of each other.
Is to set. The release lever 33 and the release cam 35 are connected by a gear. The release lever 33 has three positions, a feed position, a thick paper set position, and a plain paper set position, and each position is provided at an angular position interval of about 20 ° to 50 °. This release lever 33
Release cam 35 is about 90 °
The gear ratios are set so as to rotate each time. In the feed position, the release cam 35 is
1 pressing part 21 c and separating claw 17 pressing part 17
Does not work for c. It is in this position during normal paper feeding. At the thick paper set position, the release cam 35 pushes down only the pushing-down portion 21c of the pressure plate 21, so that the separation claw 17 is lowered along the pressure plate 21 and the thick paper can be set without putting the separation claw 17 on the recording sheet P. In the plain paper setting position, the release cam 35 pushes down both the press-down portion 21c of the pressure plate 21 and the press-down portion 17c of the separation claw 17, so that the separation claw 17 is
, It is possible to set plain paper in which the separation claw 17 is applied to the recording sheet P.

The above-described gear group (excluding the feed roller shaft 79), the separation claw 17, the release lever 33, the release cam 35, and the like are provided on a shaft provided on the right side plate of the base 20, and the center of the shaft is provided. It is configured to be rotatable.

Next, the operation and control of the paper supply unit 11 during paper supply will be described in detail.

FIGS. 10 and 11 show flowcharts of the overall control, and FIGS. 8 and 9 show explanatory diagrams of the sheet feeding operation. As shown in the figure, this control can be roughly divided into a case where the paper feed roller 5 is at a predetermined initial position and a case where there is no trouble. First, control when the paper feed roller 5 is at a predetermined initial position will be described.

In step S201 in FIG. 10, in response to the signal of the sheet feeding start, first in step S202, the carriage 5
0, and the drive switching arm 66 is moved so that the drive of the transport roller 36 can be transmitted to the sheet feeding unit (ASF position). Next, in S203, the state of the roller sensor 71 is determined, and if the paper feed roller 5 is at the initial position, the process proceeds to S204;
Proceed to 220. If the paper feed roller 5 is at the initial position, the paper feed roller 5 is rotated in S204, and
At 05, the edge of the sensor plate 69 is detected, and the drive pulse of the LF motor 47 after the detection is counted (N1).
By doing so, accurate control can be performed by accurately managing the angular position of the paper feed roller 5.

When the paper feed roller 5 is rotated by about 60 ° and the circular portion of the paper feed roller rubber 67 comes to a position facing the recording sheet P, the release cam 31 rotating in conjunction with the paper feed roller 5 pushes the pressure plate. The paper feed roller rubber 67 is released by releasing
And the recording sheet P are pressed against each other by the urging force of the pressure plate spring 72, so that a conveyance force of the recording sheet P is generated. (FIG. 8
(a)). In S207 and S208, the PE sensor 42 detects the leading edge of the conveyed recording sheet P. If the PE sensor 42 cannot detect the leading edge of the recording sheet P even if the paper feed roller 5 rotates by a predetermined amount, it means that the recording sheet P is not on the pressure plate 21 or has slipped by a certain amount or more. Then, the paper feed roller 5 is rotated to the initial position, stopped, and an error is displayed (S2).
18), and end (S219).

Within a predetermined rotation of the paper feed roller 5, P
If the E sensor 42 is turned on, the paper tip position data is obtained at S209, the angular position of the paper feed roller 5 for which the PE sensor 42 is turned on, and N2 is stored. next,
In step S210, the recording sheet P is transported to the roller pair of the transport roller 36 and the pinch roller 37, and cueing for registration is performed. In the case of the present embodiment, the PE sensor 42
Roller 31 and pinch roller 37 after
Since the distance to the roller pair is 7.5 mm and the crawling distance is 3.5 mm, a total of 11 mm is conveyed and the paper feed roller 1 is stopped (FIG. 8B). Then, in S211, the conveying roller 31 is rotated in the reverse direction to remove the leading end of the recording sheet P from the roller pair of the conveying roller 31 and the pinch roller 37.
About 7 mm is reversed, including the amount of cue and skew.

At this time, since a planetary gear (not shown) for transmitting the drive to the paper feed roller 5 is separated from the input gear 25,
No reverse drive is transmitted to the paper feed roller 5. Further, since the paper feed roller 5 is pressed against the pressure plate 21 via the recording sheet P, if the recording sheet P is sent in reverse by the transport roller 31 for registration of the recording sheet P, the elasticity of the recording sheet P is increased. , The feed roller 5 is applied in the reverse direction. However, the feed roller 5 is fixed because the clutch spring 77 provided in the clutch gear 30 works in the tightening direction. A loop can be formed and the tip can be registered (Fig. 8 (c)).
).

Next, in step S212, the paper feed roller 5 is rotated to an initial position where the half-moon portion faces the recording sheet P. During this operation, the release cam 31 pushes down the push-down portion 21c of the pressure plate 21 again, so that the pressure plate 21 can be released again (FIG. 9D). In this state, the leading end of the recording sheet P protrudes from the leading end of the nozzle of the recording head 49 by more than a predetermined margin 1.5 mm. Therefore, as shown in S213, the transport roller 36 is rotated in the reverse direction, and in the present embodiment, the transport roller 36 and the pinch roller 37 are rotated by 1 in the present embodiment.
Return to the position of 1.5 mm (FIG. 9 (e)). The return amount can be calculated from the paper tip position data N2 described above. Then, in S214, the carriage 50 is moved,
The drive switching arm 43 is moved so that the drive of the transport roller 36 cannot be transmitted to the sheet feeding unit. Next, S215
The forward rotation of the conveying roller 36 for removing the backlash of the gear is performed, and the 0.7 mm recording sheet P is conveyed.
A margin of 1.5 mm from the nozzle tip of the recording head 27 to the tip of the recording sheet P can be realized (FIG. 9 (f)).

Next, control in the case of a trouble in which the paper feed roller 5 is not at a predetermined initial position at the start of paper feed will be described.

First, in steps S220 to S223, in order to detect the angular position of the paper feed roller 5, the paper feed roller 5 is rotated, and the roller sensor 71 detects the angular position of the paper feed roller 5. At this time, the signal of the PE sensor 42 is read because the recording sheet P may be conveyed by the rotation of the paper feed roller 5. The paper feed roller 5 is a roller sensor 71
If the PE sensor 42 is turned on before is turned on,
The driving pulse of the LF motor 47 is counted to detect the position of the leading edge of the paper (N3). In S221, the angular position of the paper feed roller 5 can be detected with the roller sensor 71 turned ON. In this state, in S224, N
If 3 = 0, the leading end of the recording sheet P has not yet reached the PE sensor lever 41, and the above-described control in which the sheet feeding roller 5 is at the initial position is possible.
05 control can be entered.

When the PE sensor 42 is ON, the rotation of the paper feed roller 5 is continued, and the edge of the sensor plate 69 is detected in S225 to S227, and the LF motor 4 after the detection is detected.
By counting (N1) the drive pulses of No. 7, the angular position of the paper feed roller 5 is accurately managed, so that accurate control can be performed. Also, the drive pulse count (N
From 3), paper tip position data indicating the position of the leading edge of the recording sheet P is obtained and stored (N4).

Then, in step S228, it is determined whether the leading end of the recording sheet P has reached the roller pair of the conveying roller 36 and the pinch roller 37 by comparing with the N4 predetermined pulse.
If the leading end of the recording sheet P is between the PE sensor and the transport roller 36, the process proceeds to S229. If the leading end of the recording sheet P is ahead of the transport roller 36, the process proceeds to S236.

First, the control in the former case will be described.

First, in S229, the release cam 1
Releases the pressure plate 21, rotates the paper supply roller 5 until the circular member of the paper supply roller rubber 67 is pressed against the pressure plate 21 via the recording sheet P, and furthermore, the shortage from the leading end of the recording sheet P to the transport roller 36. Then, the paper feed roller 5 is rotated by a cue amount of 3.5 mm for registration. Then, similarly to S211 described above, the transport rollers 3
6 is reversed, the 7 mm recording sheet P is returned, and registration is performed.

Next, in step S231, the paper feed roller 5 is rotated to an initial position where the half-moon portion faces the recording sheet P. During this operation, the release cam 31 pushes down the push-down portion 21c of the pressure plate 21, whereby the pressure plate 21 can be released. In this state, the leading end of the recording sheet P is more than the predetermined margin 1.5 mm from the leading end of the nozzle of the recording head 49. Therefore, as shown in S232, the transport roller 36 is rotated in the reverse direction, and the roller pair of the transport roller 7 and the pinch roller 37 is returned to the position of 11.5 mm in this embodiment. The return amount is calculated from the paper tip position data N4 in S226. After that, since it can be performed in the same manner as in the case where the paper feed roller 5 is at the initial position at the beginning, the control of S214 is started, the control of S214 and S215 is performed, and the paper feed is completed.

Next, the control in the case where the recording sheet P exits before the roller pair of the transport roller 36 and the pinch roller 37 at the branch point in S228 will be described.

First, in step S233, in order to reduce the loop amount of the recording sheet P for registration, the sheet feeding roller 5 is rotated until the sheet feeding roller rubber 67 does not contact the recording sheet P. And S234
, The recording sheet P is returned from the conveying roller 7 by about +7 mm, and the conveying roller 36 and the pinch roller 37 are returned.
The leading edge of the recording sheet P is removed from the pair of rollers. The amount by which the recording sheet P has been ejected from the transport roller 36 is determined in S226.
From the paper tip position data N4. At this time, since the recording sheet P and the sheet feeding roller 1 are not in contact with each other, the recording sheet P can slide on the pressure plate 21 or the recording sheet P stacked immediately below and return without forming a loop.

Next, in step S235, the sheet feeding roller 5 is rotated, and the recording sheet P is fed by a cue amount of 3.5 mm for registration. Then, similarly to the above-described S211, the transport roller 36 is reversed in S236 to return the 7 mm recording sheet P, and registration is performed.

Next, in step S237, the paper feed roller 5 is rotated to an initial position where the half-moon portion faces the recording sheet P. During this operation, the release cam 31 pushes down the push-down portion 21c of the pressure plate 21, whereby the pressure plate 21 can be released. In this state, the leading end of the recording sheet P is more than the leading end of the nozzle of the recording head 49 by a certain amount larger than a predetermined margin 1.5 mm. Therefore, in S238, the transport rollers 3
6 is reversed, and a predetermined amount is returned to a position of 11.5 mm from the roller pair of the transport roller 36 and the pinch roller 37 in this embodiment. After that, the feed roller 5
Can be performed in the same manner as in the case where
Then, the control of S214 and S215 is performed, and the sheet feeding is completed. <Embodiment 2> A second embodiment will be described with reference to FIGS.

[0056] On both sides of the pressure plate 21 receives a cam for receiving a cam portion 5 d, 5e of the paper feed roller 5 21a, 21
The pressure plate 21 is kept pressed down by the cam portions 5d and 5e of the paper feed roller as shown in FIG. Here, the cam portion 5 of the feed roller 5
The shapes of d and 5e are shifted such that when the paper feed roller 5 rotates in the paper feed direction ((b) in the drawing), the cam portion 5d on the separation claw 17 side is separated from the cam receiver 21a first. It is. Therefore, in the standby state, when the pressure plate 21 in the state of (a) in FIG. 14 starts the rotation of the paper feed roller 5 according to the paper feed instruction, the phase shift of the cam parts 5d and 5e causes the cam plate 5d to shift first. The pressure plate 21 on the separation claw 17 side is pushed up by the thick leaf spring 72, and the roller portion 5c on the separation claw 17 side always comes into contact with the recording sheet P first.

Therefore, in the above-described embodiment, as in the first embodiment, the delay due to the resistance of the separation claw 17 at the time of separation can be eliminated, and skewing and paper jam can be prevented.

<First Embodiment of the Second Invention> FIG. 15 is a perspective view showing a first embodiment of the automatic paper feeder of the present invention, and shows a case where the automatic paper feeder is attached to an ink jet recording apparatus. In FIG. 15 , reference numeral 49 denotes an ink jet recording head, which discharges ink from a discharge port (not shown) using energy generated by an electrothermal conversion pair. The ink jet recording head 49 is attached to the carriage 50. The carriage 50 is driven by a motor 53 via a timing belt 55, and moves in the width direction of the recording medium along the guide shafts 50 and 51. At this time, recording on the recording medium is performed by the inkjet recording head 49. Do.

[0059] 36 is a conveying roller, it is rotated through the gear 25 or the like by the motor 47, the automatic sheet to be described later
The recording medium automatically fed from the paper device 11 is conveyed in cooperation with the pinch roller 37 pressed against the recording medium. A discharge roller 59 is provided for discharging the recording medium after recording from the recording unit. Discharge roller 5
Reference numeral 9 is interlocked with the conveyance roller 36, and discharges the recording medium while nipping the recording medium between the spur 61 (see FIG. 17 ) pressed against the conveying roller 36. The spurs 18 are in point contact with the recording surface so as not to transfer excess ink to the recording medium. Reference numeral 46 denotes a platen, which guides a recording medium to a recording position and supports a discharge roller 59.

Reference numeral 16 denotes an ejection recovery processing device, which functions to remove clogging due to thickening of ink in the ink ejection ports of the ink jet recording head 49 and keeps the ink ejection state good.

Reference numeral 11 denotes an automatic paper feed mechanism, in which a recording medium is loaded.

FIG. 17 is a side sectional view showing a state in which the automatic paper feeder 11 according to the first embodiment of the present invention is mounted on the ink jet recording apparatus 1. In the automatic paper feeder 11, the recording sheet P is set on the guide slope 125 with the back surface supported by the pressure plate 21, and the pressure plate 21 is pressed by a spring 72 provided between the recording sheet P and the base 20, and the recording sheet P is pressed. P is pressed against the feeding roller 122 or the roller 123. Generally, the feed roller 120 is a high friction member (rubber member or the like), and the roller 123 is formed of plastic.

When the feed roller 120 rotates, one sheet of the recording sheet P which is in contact with the feed roller 122 is sent to the downstream side by the frictional force. Restricting means for applying a force that resists feeding to the entire recording sheet P in order to prevent the occurrence of a situation in which the recording sheet P and subsequent recording sheets P are successively fed out by the frictional force of each other. Is provided with a claw 127 for pressing the corner of the leading end of the recording sheet P. Due to the claw 127, only the first recording sheet P sent out from the feeding roller 122 with a larger frictional force than the frictional force between the recording sheets P overcomes the regulating force of the claw 127 and proceeds downstream. Yes, separation is complete.

After the separation, the recording sheet P is conveyed to a recording position and recorded by the recording apparatus 1. At the time of recording, in order to prevent the load of the automatic paper feeder 11 from affecting the conveyance performance of the conveyance roller 36 and the pinch roller 51, the feeding roller 122 is formed into a half-moon shape, and a frictional force is applied to the separated recording sheet P. Not touching so that it does not affect (state in the figure)
And the roller 123 comes into contact with the recording sheet P while rolling.

Reference numeral 125 denotes a guide member for guiding the recording sheet P to the inside of the claw 127.

FIG. 18 is a perspective view showing the automatic sheet feeder 11 of the present invention best, and shows a state in which the feed roller 122 starts to rotate and the recording sheet P is slightly fed. A bend 130 is generated in the vicinity of the separation claw 127 of the recording sheet P. At this time, the guide means 125 of the present invention rotates simultaneously with the feeding roller 122 and is in a state of not contacting the bend 130.

FIG.19Is a notation at the time of separation from the guide member 125.
FIG. 6 shows the relationship between the recording sheet P and the deflection 130.19
(A) is the separation standby state, figure19(B) immediately after the start of separation
Indicates the status. Guide member 125 and deflection of recording sheet P
130 are completely separated.

The distance R ₁ from the axial center of the feed roller 122 of the guide member 125 to the farthest portion, the radius R ₂ of the arc of the feed roller 122, the feed roller 122 after feeding, and the recording sheet P Radius R of the roller 123 to avoid contact
Assuming that they are ₃ , they have a relationship of R ₁ ≦ R ₃ <R ₂ . <Embodiment 2> FIG. 20 is a guide instead of the guide member 125 members 13
1, and shows a case in which it is moved by driving a solenoid 132 or the like. The distance of the guide member 131 and the pressure plate and L _1, the distance of the sheet contact surface of the separation claw and the pressure plate L
₂ to the L ₁ ≦ L ₂ In a relationship. <Embodiment 3> FIG. 21 is a perspective view showing a third embodiment, the feed roller 1
22 is only one. Example 4 FIG. 22 is a perspective view showing Example 4, showing a case where separation claws 127 are provided at both ends.

[0069]

According to the present invention, in an automatic paper feeder having a one-claw separation system, when a rotary feeder close to a separating unit is always separated from another rotary feeder at the time of separation. Since the recording sheet is brought into contact with the recording sheet before the sheet is fed, the delay due to the resistance of the separation unit can be eliminated, and it is possible to compensate for serious disadvantages such as skew and paper jam. In addition, since the above-mentioned drawbacks can be compensated for, it is possible to provide a low-cost, high-reliability, and compact automatic paper feeder. <Effect of the Second Invention> According to the present invention, a loading unit capable of loading a recording sheet,
A rotary feeder provided for sending out a recording sheet from the loading means, and an end of the recording sheet loaded on the loading means is regulated, so that the recording sheet is fed at the time of feeding by the rotary feeder. In an automatic paper feeder having a separation claw that separates one sheet at a time, a leading edge of a recording sheet is guided to the inside of the separation claw near the separation claw, and a guide member that separates from the recording sheet is provided at the time of separation. The recording sheet is separated smoothly instead of the guide member pushing the deflection generated at the corner portion of the recording sheet at the time.

[Brief description of the drawings]

FIG. 1 is a perspective view of an automatic feeding device to which the first invention is applied.

FIG. 2 is a front view of the automatic feeding device.

FIG. 3 is a side view of the automatic feeding device.

FIG. 4 is a side view of the automatic feeding device.

FIG. 5 is a vertical sectional side view of the sheet feeding unit.

FIG. 6 is a vertical side view of the sheet feeding unit.

FIG. 7 is a vertical sectional side view of the paper feeding unit.

FIG. 8 is an operation diagram of a sheet feeding operation.

FIG. 9 is an operation diagram of a sheet feeding operation.

FIG. 10 is a control flowchart of the automatic feeding device.

FIG. 11 is a control flowchart of the automatic feeding device.

FIG. 12 is a side view of the rotary feeder.

FIG. 13 is a perspective view of the sheet feeding unit.

FIG. 14 is a front view of the sheet feeding unit.

FIG. 15 is a perspective view of an automatic feeding device to which the second invention is applied.

FIG. 16 is a perspective view of a conventional paper feeding unit.

FIG. 17 is a vertical sectional side view of the automatic feeding device.

FIG. 18 is a perspective view of the sheet feeding unit.

FIG. 19 is a vertical sectional side view of the sheet feeding unit.

FIG. 20 is a vertical sectional side view of a sheet feeding unit according to another embodiment.

FIG. 21 is a vertical sectional side view of a sheet feeding unit according to another embodiment.

FIG. 22 is a longitudinal sectional side view of a sheet feeding unit according to another embodiment.

FIG. 23 is a vertical sectional side view showing a conventional paper feeding unit.

[Explanation of symbols]

 P Recording sheet 5 Paper feed roller (rotary feeder) 5A Contact portion 17 Separating claw (separating means) 21 Pressure plate (stacking means) 120 Paper feed roller (rotary feeder) 125 Guide member 127 Separating claw 131 Guide member

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Haruyuki Yanagi 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Masahiro Taniguro 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc. (72) Inventor Hideaki Kawakami 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Hiroyuki Kinoshita 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Hiroyuki Saito 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc. (72) Inventor Soichi Hiramatsu 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc. (56) Reference Reference JP-A-57-81037 (JP, A) JP-A-62-121229 (JP, U) (58) Fields investigated (Int. Cl. ⁶ , DB name) B65H 1/00-3/68

Claims (7)

(57) [Claims] 1. An automatic feeding device for separating and feeding recording sheets stacked on a stacking unit one by one, wherein the recording sheet is sent from the stacking unit and the recording is performed.
An arc portion contacting the sheet, and an arc contacting the recording sheet.
A plurality of coaxially provided rotary feeders having a non-portion, and a portion in front of the feed direction of the recording sheets stacked on the stacking means.
Disposed on one side angle end, and a separating means for separating one by one the recording sheet fed by said rotary sheet Okukarada, side closer to the separating means of said plurality of rotary sheet Okukarada
The arc part of the rotary feeder is larger than the arc part of the other rotary feeder.
Of the arc portion so as to contact the recording sheet first.
An automatic feeding device characterized in that the phase of the side contacting the recording sheet is shifted . (2) One recording sheet loaded on the loading means
In an automatic feeding device that separates and feeds each, The recording sheet is provided coaxially to feed the recording sheet from the loading means.
A plurality of rotating feed bodies, Before the feeding direction of the recording sheets stacked on the stacking unit
Disposed at one side corner of the end and fed by the rotary feeder.
Separating means for separating the obtained recording sheets one by one; When the recording sheet is loaded on the loading means,
A pressure plate both of which are biased toward the rotary feeder, While pressing the pressure plate, the recording sheet is
Is rotated together with the rotary feeder so that
The rotary feeder for releasing pressure is provided at both ends of the rotary shaft.
Cam part, With Of the plurality of rotary feeders, a side closer to the separating means
The recording sheet is provided such that the rotating feeder is earlier than other rotating feeders.
The phase of the cam section is shifted so that it contacts Specially
Automatic feeding device. 3. A stacking means capable of stacking recording sheets, a rotary feeder provided for feeding the recording sheets from the stacking means, and an end of the recording sheets stacked on the stacking means. When feeding by the rotary feeder,
A separating claw for separating the recording sheets one by one, wherein a leading edge corner of the recording sheet supplied to the stacking means is guided to the inside of the separating claw in the vicinity of the separating claw, and at the time of separation, An automatic feeding device provided with a guide member separated from a recording sheet. 4. The automatic feeding device according to claim 3, wherein the guide member is provided on a shaft of the rotary feeder. 5. The guide member according to claim 1, wherein said guide member is located at an axis center of a rotary feeder.
Distance R to the farthest part₁ The radius R of the circular arc of the rotary feeder_Two ,
To avoid contact between the rotating feeder and the recording sheet after feeding
Roller radius R_Three Is R₁ ≤R_Three <R _Two  5. The automatic feeding according to claim 4, wherein
apparatus. 6. A distance L ₁ between the guide member and the pressure plate, a distance L ₂ between the uppermost portion of the separation claw and the recording sheet contact surface and the pressure plate.
4. The automatic feeding device according to claim 3, wherein the following relationship is satisfied: L ₁ ≦ L ₂ . 7. The method according to claim 1, wherein:
An image forming apparatus comprising the above-described automatic feeding device.