JP2522391B2 - Sheet material feeder - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a sheet material feeding device that separates and feeds sheet materials one by one from a sheet material stack.

In the above, the sheet material is, for example, a copying machine, a printer,
Sheets of paper such as transfer paper, photosensitive paper, thermal paper, electrostatic recording paper, printing paper, originals, cards, envelopes, etc. supplied to office equipment such as printing machines and other equipment using various sheet materials (Cut sheet). The material is not limited to paper.

(Prior Art) Generally, in a paper feeding device (sheet material feeding device) of office equipment such as a copying machine, a large number of sheet materials (paper) such as transfer paper and photosensitive paper are placed on a sheet material receiving substrate of a cassette or a deck. Sheets are stacked, and the sheet material is separated and fed one by one from the sheet material stack to the next step by a sheet feeding roller or other feeding means.

At this time, in order to prevent the double feeding of the sheet material, a separation claw is provided near the tip of the sheet material stacking body in the sheet material feeding direction, and when the uppermost sheet material is fed, a slight amount is added to the tip portion. By making an operation to pass over the separating claw while forming a flexible loop, the uppermost sheet material is separated from the next lower sheet material and below so that only one sheet material is fed. Is known (separate claw method).

FIG. 13 shows a perspective view of a main part of an example of a separating claw type feeding device.

100 is a sheet material loading platform as a sheet material receiving substrate, 101
Is a spring that lifts and urges this sheet material loading platform, P
Is a sheet material (cut sheet, paper) of a certain size stacked on the stacking table, 102 is a feeding roller, and 103 is the upper surface of the left and right corners of the leading end side of the stacked sheet material P in the feeding direction. It is a pair of left and right separating claws.

The upper surface of the stacked sheet material P near the leading end is in contact with the lower surface of the feeding roller 102 with a predetermined pressing force by the lifting force of the sheet material stacking table by the spring 101. Alternatively, the feeding roller descends for each feeding signal and comes into contact with the upper surface of the stacked sheet material P with a predetermined pressing force.

The separating claw 103 can freely swing up and down about the shaft 103a, and is engaged with the upper surface of the corner portion of the leading edge of the stacked sheet material P by its own weight.

The feeding force in the feeding direction acts on the uppermost sheet material P1 of the stacked sheet material P in which the feeding roller 102 is rotationally driven in the sheet material feeding direction, by a frictional force. The uppermost sheet material P1 to which the feeding is applied tries to move forward, but the corner portions on the left and right of the leading end side thereof are received by the separating claws 103 and are prevented from moving forward. Therefore, as the feeding roller 102 rotates, the uppermost sheet material P1 is bent at the portion near the separating claw between the separating claw 103 and the feeding roller 102 against the strength of the sheet material (waist). Loop A can be made.

When the size of the flexure loop A exceeds a certain level, the repulsive force that attempts to restore the flexure to the original position causes the corner portions of the uppermost sheet material P1 on the left and right sides of the leading edge held by the separation claw 103 to separate claws. It naturally comes off from the lower surface side of the to the upper surface side and gets over the separation claw. That is, only the uppermost sheet material P1 of the stacked sheet material P is released from the restraint of the separating claw by the formation of the flexible loop A, and only one sheet material is separated and fed from the next and lower sheet materials (two-dot chain line shown. ).

(Problems to be Solved by the Invention) In such a separating claw type sheet feeding device, the sheet materials to be separately fed one by one are thick sheet materials such as official postcards, book cards and envelopes (so-called plain paper). If the sheet material is stiffer than the sheet material), the strength of the sheet material (such as hardness and elasticity of the sheet material) overcomes the sheet material feeding force of the feeding roller 102, and the feeding is performed with the separating claw 103. Laura 1
Whether the flexible loop A of the sheet material as described above is not formed with 02 or is insufficiently formed, and eventually it is impossible to separate and feed one sheet without being able to ride over the separation claws. There is no nature. If you try to separate the sheet material by applying a strong feeding force, the corners of the thick edge of the thick sheet material will break when the corners pass over the separation claws, and this break will cause a jam, and further In some cases, it caused equipment failure.

Therefore, in the case of a thick sheet material, a feeding device such as a retard roller type is used, but the device has a drawback that it is expensive and has a large-scale device configuration.

The present invention has been made in view of the above, and provides a sheet material feeding device capable of feeding thick special paper with good separation / feeding performance without requiring a complicated configuration and device. The purpose is to provide.

(Means for Solving Problems) According to the present invention, a sheet feeding means is provided in contact with an uppermost portion of a sheet material stack to give a feeding force to the sheet material, and a sheet material stack front end surface in the sheet material feeding direction. It has a first restricting portion that is in contact with and regulates the movement of the sheet material stack in the feeding direction, and a second restricting portion that contacts the uppermost portion of the sheet material stack and regulates the vertical direction of the sheet material stack. There is a gap α in the sheet material advancing direction between the uppermost portion of the sheet material passage surface of the first regulation portion and the sheet material stack contact surface of the second regulation portion.
Is smaller than the thickness of one sheet material of the sheet material stack,
A gap β perpendicular to the sheet material advancing direction is provided between the uppermost portion of the sheet material passage surface of the first regulation portion and the sheet material stack contact surface of the second regulation portion, and the first regulation portion The sheet material is separated by passing over the sheet and passing through the gap β, and the first regulation portion and the second regulation portion are swingably supported along the stacking direction of the sheet material. The sheet material feeding device is characterized in that

Further, according to the present invention, in the sheet material feeding device having the above structure, the upper portion of the first regulating portion is inclined forward as the sheet material feeding direction is directed upward, and the second regulating portion is the sheet material depositing body. Of the sheet material stack in the up-and-down direction behind the front end of the sheet feeding direction, the gap β is set in the range of 2 to 10 mm, and the front inclined surface of the first regulating portion is the sheet material. The coefficient of friction of the slope portion where the tip of the uppermost sheet material of the stack abuts is μ1, and the friction coefficient of the slope portion where the tip of the sheet material lower than the uppermost sheet material abuts is μ2.
The sheet material feeding device is characterized by having a relationship of μ1 <2.

(Operation) In the above configuration, when a feeding force is applied to the uppermost sheet material of the sheet material stack by the feeding means, the tip of the uppermost sheet material passes over the first restriction portion and the gap β
When the sheet material passes through the sheet, the regulation by the first regulation portion is released, and the uppermost sheet material is fed through the gap (gate) between the first regulation portion and the second regulation portion. To go. At this time, even if the second or lower sheet material under the uppermost sheet material is moved by the frictional force with the fed uppermost sheet material, the tip of the second or lower sheet material is Since the conveyance force by the frictional force of the sheet material that is received by the first restriction unit cannot overcome the first restriction unit,
There is no double feeding in which the uppermost sheet material being fed out comes out with the second and subsequent sheet materials.

That is, instead of forming a flexible loop in the sheet material and separating and feeding one sheet as in the separation claw method described above, the gap (gate) between the first and second restriction portions with respect to the sheet material stack is Since only one sheet is separated and fed by passing only the uppermost sheet to which the feeding force is applied, it is strong and unsuitable for separating and feeding one sheet by the separating claw method. It is possible to separate and feed one sheet with good performance.

The upper portion of the first restriction portion is inclined forward as it goes upward, so that the tip end of the fed uppermost sheet material is slid and guided upward by the inclined surface. Smoothly overcome the regulatory department.

By partially differentiating the friction coefficient of the inclined surface as described above (μ1 <μ2), the tip of the uppermost sheet material smoothly rides over the first restricting portion, and the second and subsequent sheets below it. The leading end of the sheet material is reliably regulated to prevent the second and subsequent sheet materials from being dragged by the uppermost sheet material and crossing over the first regulation portion, thereby preventing double feed.

Since the first restricting portion and the second restricting portion are swingably supported along the stacking direction of the sheet material, the sheet material feeding means is pressed against the upper surface of the sheet material when the sheet material is sent out. When the sheet material stack is pushed down by means of the sheet material, the first and second regulating parts also follow the lowering of the sheet material, so that the relative position between the tip of the sheet material and the regulating portion is always constant and stable. The separated sheet materials can be separated.

(Embodiment) Embodiment 1 (FIGS. 1 to 4) In FIG. 1, reference numeral 45 denotes a sheet material stacking base as a sheet material receiving substrate, which is urged upward by an urging means not shown. . P is a sheet material (sheet material stack) stacked on the stacking table 45, and 26 is a feeding roller located above the stacked sheet material. The feeding roller 26 is an open-circle roller, and normally, the open-side 26a of the feed roller 26 is faced downward so that the feed roller 26 is in a non-contact rotation angle posture with respect to the upper surface of the stacked sheet material and is on standby. When the feeding roller 26 is driven to make one rotation in the sheet material feeding direction, the circumferential portion 26b comes into contact with the upper surface of the stacked sheet material P, and the uppermost sheet material P1 is frictionally exerted so that the feeding force in the feeding direction is increased. To work.

50 and 50 are a pair of left and right sheet material separating levers, which are freely swingable up and down around a shaft 51 on the inner surface of a side wall (not shown) disposed on the left and right sides of the sheet material stacking table 45. I am allowed.

Each of the left and right sheet material separating levers 50, 50 comes into contact with the front end surface of the stacked sheet material P in the sheet feeding direction on the stacking table 45 to regulate the movement of the stacked sheet material P in the sheet feeding direction. Restricting portion 56 (hereinafter referred to as front end restricting member) and stacked sheet material P
Has a second restricting portion 55 (hereinafter referred to as a height restricting member) that abuts on the uppermost part of the stacking sheet material P and restricts the vertical direction of the stacked sheet material P. In the free state, the left and right sheet material separating levers 50, 50 have a turning force downward about the shaft 51 due to their own weight, and the stacked sheet material P near the left and right corners on the leading edge side of the stacked sheet material P. The height regulating members 55, 55 are hooked on the upper surface portions, respectively, and are in a state of being stuck. Moreover, each front end regulating member 56
56 is in a state of facing the surface portions of the left and right end surfaces of the front end surface of the stacked sheet material P.

FIG. 2 shows the sheet material separating lever 50 on the right side in FIG.
3 is a perspective view of only the front end regulating member 56 and the height regulating member.
It is an enlarged side view of 55 parts.

In this embodiment, the height regulating member 55 is the stacked sheet material P.
The stacked sheet material P is regulated in the vertical direction behind the front end of the sheet feeding direction. The front end regulating member 56 is inclined as a slope portion 56a toward the front in the sheet material feeding direction as it goes upward with respect to its upper portion. A gap α in the sheet material advancing direction is present between the uppermost portion 56b of the sheet material passage surface of the front end regulation member 56 (FIG. 3) and the stacked sheet material contact surface 55a of the height regulation member 55, The gap α is set to be smaller than the thickness of one sheet material of the stacked sheet material P. Further, a gap β perpendicular to the sheet material advancing direction is present between the uppermost portion 56b of the sheet material passage surface of the front end regulation member 56 and the stacked sheet material contact surface 55a of the height regulation member 55. β is 2
It is set in the range of 10 mm.

A process of separating and feeding one sheet material by the sheet material feeding device having the above configuration will be described with reference to FIG.

First, when the feeding roller 26 is driven, the uppermost sheet material P1 of the stacked sheet material P is fed by the frictional force with the driving roller 26, but the height regulating member 55 and the front end regulating member 56 in the feeding direction. Since the gap α is smaller than the thickness of one sheet material, the front end regulating portion 56 prevents the advance of the sheet material being fed. Therefore, the fed out uppermost sheet material P1 slides on the sloped portion 56a of the front end regulating member 56, climbs over it, and is fed to the intermediate transfer roller (not shown). 4 (a), (b), and (c) show the state, and as the feeding roller 26 rotates, the figure (a) →
It changes from (b) to (c).

Figure (a) shows the set state. When the feeding roller 26 starts to rotate, the uppermost sheet material P1 is fed, but the second sheet material P2 is also fed with the feeding of the uppermost sheet material P1 as shown in FIG. The frictional force with the upper sheet material P1 may be taken out in the same direction as the uppermost sheet material P1. However, the uppermost sheet material P1 that has received the large conveying force of the feeding roller 26 is the slope portion 56 of the front end regulating member 56.
Compared to climbing up a easily, the feeding force due to the frictional force between the sheet materials is weak, so the second sheet material P2 must climb over the slope 56a of the front end regulating member 56 as shown in FIG. I can't. At this time, the sheet material is sliding while bending, but the bending position varies depending on the strength of the used sheet material. However, since there is the height regulating member 55, the upward bending does not occur in the rear direction in the sheet material feeding direction by the height regulating member 55, and is in front of the height regulating member 55 or at the front end thereof. It will be a department.

That is, the height regulating member 55 regulates the height of the sheet material and also regulates the bending position. When the bending position occurs in front of the height restricting member 55, there is a possibility of double feeding.

Therefore, if the height regulating member 55 is performed in front of the position where the sheet material originally bends, the bending position is the front end portion of the height regulating member 55, and a large force is required to get over the slope portion 56a. No more double feeding. Moreover, if it goes too far forward, the uppermost sheet material P1 can no longer get over the inclined surface portion 56a even by the conveying force of the feeding roller 26, and a sheet feeding failure occurs. In this embodiment, the uppermost portion 56b of the sheet material passing surface of the front end regulating member 56 and the stacked sheet material contact surface 55a of the height regulating member 55 have a clearance β of 2 to 10 mm perpendicular to the sheet material advancing direction. By setting it in the range of 3, it was possible to obtain good feeding conditions without causing double feeding or paper feeding failure.

That is, the relationship between the feeding force required for the sheet material to slide over the sloped portion 56a of the front end regulating member 56, the feeding force of the feeding roller, and the frictional force between the sheet materials is calculated. By the relation of feed force> conveyance force required to get over> frictional force between sheet materials, it is impossible or difficult to form a flexible loop and separate and feed one sheet by the separating claw method. -Even if a special thick sheet material such as a book sheet or an envelope is used, it is possible to reliably separate and feed one sheet material without double feeding the sheet material.

As the consumption of the stacked sheet material P decreases, the sheet material stacking table
45 is successively lifted by push-up biasing means (not shown). As a result, the height level of the topmost sheet material P1 of the stacked sheet material P on the stacking table 45 is pressed against the height regulating member 55 and is constantly maintained at a predetermined substantially constant level. Sheet feeding is always stable.

Second Embodiment (FIG. 5) The first embodiment described above has a structure in which the leading end portion of the uppermost sheet material P1 fed by the feeding roller 26 is pushed up so as to get over the slope portion 56a of the front end regulating member 56. The tip of the sheet material P1 receives a drag force from the slope when trying to get over the slope portion 56a, and the bending point is determined by the relationship between the received drag force and the stiffness of the sheet material. Therefore, if the bending point is farther than the front end of the sheet material that rides on the slope, the moment of the drag force that the sheet material receives is constant, so even if the sheet material has the same conveying force, it bends even a fairly thick sheet material. Then get over the slope 56a.

What has been described above has a relationship between the position that regulates the height of the uppermost portion of the sheet material, the distance that regulates the front end of the sheet material, and the stiffness of the sheet material used. It does not matter if the height of the sheet material is restricted behind the point where the sheet material bends, but if the height is restricted before the point where the sheet material bends, the height of the bending point It becomes the point of regulation. In view of the above, the present embodiment (FIG. 5) allows the height regulating member 55 to be adjusted in position before and after the sheet material feeding direction so that the clearance between the member 55 and 56 is perpendicular to the sheet material traveling direction. By adjusting β, the bending point of the sheet material is adjusted.

FIG. 5 shows a perspective view of a sheet material separating lever 50 provided with a height regulating member 55 so that its position can be adjusted. That is, the height regulating member 55 is a member separate from the lever 50, and the member 55
A longitudinal slot 55b in the front-rear direction, and by engaging this slot 55b with a boss 57 provided on the lever 50 side, the height restricting member 55 is provided to the lever 50 by the slot 55b and the boss 57. It is provided so as to be slidable in the longitudinal direction of the sheet material in the longitudinal direction of the sheet material while maintaining a constant height and in the longitudinal direction of the sheet material feeding direction.
By moving the member 55 forward to move it to a position closer to the front end regulating member 56, the gap β between the members 55 and 56 becomes smaller. On the contrary, by moving the member 55 backward to move it to a position away from the front end regulating member 56, the gap β becomes large. The member 55 can be fixedly held at a position moved by sliding by a fixing means (not shown).

As described above, if the height of the sheet material is regulated at a position away from the end of the sheet material on which the sloped portion 56a is to be ridden, the sheet material can easily be ridden, and if the height is regulated at a distance that is short, it is difficult to ridden the sheet material. That is, when an extremely thick sheet material is used, the front end regulating member 56 and the height regulating member 55 are separated from each other in FIG.
If you set the member 55 at the position shown by the dotted line and use paper that is close to thin paper, set the member 55 at the position shown by the solid line where the height restriction member 55 is close to the front end restriction member 56 and set the sheet material. If feeding is performed, problems such as poor paper feeding and double feeding can be further avoided from thin paper to extremely thick paper.

Embodiment 3 (FIG. 6) This embodiment is an example in which the slope portion 56a is devised to avoid double feeding. That is, the frictional force is different between the portion of the slope portion 56a with which the uppermost sheet material P1 contacts and the portion with which the second and subsequent sheet materials P2 contact. Friction coefficient μ1 to make the slope part that the topmost sheet material abut is slippery
Is made low, and the slope portion where the second sheet P2 and subsequent sheet members come into contact with each other is less slippery and the friction coefficient μ2 is increased (μ1 <μ2).

In this embodiment, some grooves 58 are formed in the slope portion of the slope portion 56a with which the second and subsequent sheets P2 of the sheet material P come into contact. Since the slope portion with which the tip of the uppermost sheet material P1 abuts is a slope without a groove, it can easily slide, but since there is a groove 58 in the slope portion with which the second and subsequent sheet materials abut,
Even if an attempt is made to climb, it becomes a resistance and cannot climb over the slope 56a, so that it is not taken out to the uppermost sheet material P1 (Fig. 6 (a) → (b)). Then, after the uppermost sheet material P1 is sent out, the sheet material loading platform 45 is pushed upward by the pushing-up urging means so that the second sheet material P2 is located at a height without the groove 58 and is the same. Things are repeated ((c)). At that time, since the slope 56a is inclined forward in the feeding direction, there is no problem when the stacked sheet material P is pushed upward.

Embodiment 4 (Fig. 7) In the above embodiment, the groove 58 is provided in order to partially differ the friction coefficient of the sloped portion 56a, but resistance is given to the sloped portion where the second and subsequent sheet materials come into contact. Is not limited to this. In the present embodiment, the friction member 59 is provided on the slope portion where the tips of the second and subsequent sheet materials come into contact. The friction coefficient of the friction member 59 is set to be larger than that of the member forming the inclined surface portion 56a. Therefore, in addition to the effect similar to that of the third embodiment, if the friction member 59 is replaceable and an appropriate friction member is set according to the sheet material used, further reliability can be obtained.

Embodiment 5 (FIGS. 8 to 12) This embodiment shows an example of a sheet material feeding device A according to the present invention and a laser beam printer B as a main body device in which the sheet material feeding device A is combined.

FIG. 8 is a vertical sectional side view of both devices A and B. The sheet material feeding device A of the present embodiment is a separate body from the printer B as a main body device, and is configured as a detachable optional unit device to be used in combination with the printer B. The sheet material feeding device A is placed on the sheet material feeding device A, and the printer B as a main body device is provided on the sheet material feeding device A with the downward projection 18 on the lower surface side of the printer on the upper surface plate 21 side of the sheet material feeding device A. The sheet material feeding device A and the printer B are fitted and engaged with the receiving holes 24 provided and positioned and placed.
And are combined with each other.

A feeding sheet material receiving port 19 is provided on the bottom surface of the printer, and is provided at the printer bottom surface position corresponding to the position of the nip portion between the sheet material feeding roller 10 and the sheet material conveying roller 12 arranged inside the printer.

The feeding sheet material receiving port 19 is provided on the sheet material feeding device A side when the printer B is positioned and mounted on the sheet material feeding device A as described above. A pair of sheet material conveying rollers 28 located on the front side of the face plate 21
-Located above 54.

I, the printer B 1 is an external casing of the printer, and the printer of this example has the right end surface side in the drawing as the front surface. 1A is a printer front plate, and the front plate is a hinge shaft 1B on the lower side with respect to the printer outer casing 1.
It is possible to freely incline and open as shown by the chain double-dashed line, and raise and close as shown by the solid line. Attaching / detaching the process cartridge 2 to / from the printer and inspecting the inside of the printer
Maintenance and the like is performed by tilting the front plate 1A open to greatly open the inside of the printer.

The process cartridge 2 of this example is a cartridge housing 2a, a photosensitive drum 3, a charging roller 4, and a developing device 5.
The cleaner 6 includes four image forming process devices, and the printer front plate 1A can be attached to and detached from a predetermined storage portion in the printer outer casing 1 by tilting and opening the printer front plate 1A as shown by a two-dot chain line. When the cartridge 2 is properly installed in the printer, the mechanical drive system and the electric circuit system on both the cartridge side and the printer side are connected to each other via a mutual coupling member (not shown), and the cartridge is mechanically and electrically connected. Integrated into.

Reference numeral 7 denotes a laser beam scanner section disposed on the inner side of the printer outer casing 1, which is composed of a semiconductor laser, a scanner motor 7a, a polygon mirror 7b, a lens system 7c, etc., and a laser beam from the scanner section 7 L enters the housing 2a almost horizontally from the exposure window 2b of the cartridge housing 2a mounted in the printer, and passes through the passage between the cleaner 6 and the developing device 5 arranged vertically in the housing. Is incident on the exposure unit 3a on the left side surface of the photosensitive drum 3, and the surface of the photosensitive drum 3 is scanned and exposed in the generatrix direction.

The sheet material conveying roller 12 is provided on the printer exterior casing 1 side. 13 is a transfer roller disposed inside the printer front plate 1A and above the sheet material feeding roller 10, 15a and 15b are fixing roller pairs provided inside the printer front plate 1A, and 14 is a transfer roller 13 and a fixing roller. A sheet material guide plate provided between 15a and 15b, 16 is a sheet material discharge roller disposed on the sheet material outlet side of the fixing roller pair 15a and 15b, and 17 is a discharged sheet material receiving tray.

When an image forming start signal is input to the control system of the printer, the photosensitive drum 3 is rotationally driven in the counterclockwise direction indicated by the arrow at a predetermined peripheral speed, and the peripheral surface thereof is charged by the charging roller 4 to a predetermined positive or negative polarity. It is uniformly charged. The charging roller 4 is a conductive member to which a predetermined voltage is applied, and the photosensitive drum 3 is charged by the roller by a so-called contact (or direct) charging method. The charging roller 4 may be driven to rotate by the photosensitive drum 3, may be driven to rotate in the opposite direction, or may not rotate. It may be a friction charging member or a corona charger.

Next, the pixel laser beam L corresponding to the time series electric pixel signal of the image information output from the laser beam scanner section 7 is incident on the uniformly charged surface of the rotating photosensitive drum 3 at the exposure section 3a, and An electrostatic latent image of image information is formed on the surface of the photosensitive drum 3 by sequentially subjecting the three surfaces to main scanning by the laser light L in the drum generatrix direction.

The latent image on the surface of the drum 3 is sequentially developed with toner by the developer carried on the developing sleeve (or roller) 5a of the developing device 5. 5b is a storage room for the developer (toner) t,
Reference numeral 5c denotes a developer agitating / conveying member in the developer accommodating chamber, which is rotationally driven in the direction of the arrow to agitate the developer t in the accommodating chamber 5b and sequentially supplies and conveys the developer to the developing sleeve 5a side. .

On the other hand, one sheet of the stacked sheet material P stored in the sheet material feeding device A is separated and fed, and introduced into the printer B from the feeding sheet material receiving port 19 on the bottom surface of the printer B. The introduced sheet material is sandwiched between the feeding roller 10 and the conveying roller 12 and drawn into the printer B, and the rotating circumference of the photosensitive drum 3 is moved toward the facing contact portion (transfer portion) between the photosensitive drum 3 and the transfer roller 13. It is fed at the same constant speed as the speed. During the feeding, the sheet material sensor PH arranged at a predetermined position of the sheet path between the roller 10 and the transfer roller 13 detects that the leading edge of the fed sheet material reaches the sensor position. There is a timing relationship at which scanning exposure (writing of image information) of image information on the surface of the photosensitive drum 3 by the laser beam scanner section 7 is started by the sheet material front end detection signal.

The sheet material fed to the transfer unit sequentially passes between the photosensitive drum 3 and the transfer roller 13, and a voltage applied to the transfer roller 13 (a voltage having a polarity opposite to that of the toner) and a photosensitive drum of the transfer roller The photosensitive drum 3 is pressed by the pressing force against the drum 3.
The transfer of the toner image on the surface side is sequentially received. The voltage is applied to the transfer roller 13 when the leading edge of the sheet material to be fed reaches the contact portion (transfer portion) between the photosensitive drum 3 and the transfer roller 13. The transfer roller 13 may be a corona charger.

The sheet material that has passed through the transfer portion is separated from the surface of the photosensitive drum 3, guided by the guide plate 14, and introduced to the fixing rollers 15a and 15b. Of the pair of fixing rollers 15a and 15b, the roller 15a on the side contacting the image transfer surface of the sheet material is a heating roller incorporating a halogen heater, and the roller 15b on the side contacting the back side of the sheet material is made of an elastic material. It is a pressure roller, and the transferred toner image is fixed on the surface of the sheet material by heat and pressure while the sheet material having undergone the image transfer passes through the roller pair 15a and 15b, and is discharged onto the tray 17 by the discharge roller 16. It is discharged as an image formed product (print).

After the transfer of the toner image, the surface of the photosensitive drum 3 is cleaned and cleaned by the cleaning blade 6a of the cleaner 6 to remove the transfer residual toner and other contaminants, and is repeatedly used for image formation.

II, Sheet Material Feeding Device A The sheet material feeding device A includes a sheet material feeder 20 having at least a sheet material feeding means and a driving means for the sheet material, and a sheet serving as a sheet material accommodating portion that can be taken in and out of the sheet material feeder. It consists of a material cassette 40.

9 and 10 show a front view and a vertical sectional view of the feeder 20, respectively. 11 and 12 show a left side view and a vertical sectional view of the sheet material cassette, respectively.

The feeder 20 includes left and right parallel pedestals 21L and 21R, an upper surface plate 21 that connects the pedestals, a feeding roller 26 having an oval circular shape, feeding roller driving means (not shown) housed in the pedestal, sheet material. It has one roller 28 of the pair of conveying rollers 28 and 54, and the like. The sheet material cassette 40 is inserted (Fig. 8) from the front side of the feeder into the space formed by the lower surface of the feeder upper surface plate 21, the upper surface of the pedestal c, and the inner side surfaces of the left and right pedestals 21L and 21R. It is pulled out by pulling to.

The sheet material cassette 40 includes a cassette body case 41, a middle plate 45 as a sheet material receiving substrate (sheet material stacking base) which is disposed in the case, and which can freely swing up and down about a rear side 45a as a fulcrum. A shaft that lifts and urges the tip side of the intermediate plate 45
A pressure lever 46 that can be tilted and tilted around 46a, a pressure shaft 47 that tilts and tilts the pressure lever 46 via a spring 49, and inner surface sides of the left and right side walls 41b and 41c of the cassette body case 41. On axis 51
It has a pair of left and right sheet material separating levers 50, 50 which are vertically rotatable about the center of the sheet material, the other roller 54 of the sheet material conveying roller pair 28, 54, and the like.

The sheet material P is stacked on the intermediate plate 45 in the cassette body case 41 and stored in the cassette. The pair of left and right sheet material separating levers 50, 50 have the same structure as those shown in the first to fourth embodiments, and the front end regulating member 56 as the first regulating portion and the second regulating portion as the second regulating portion. The height regulating member 55 is provided.

When the cassette 40 is removed from the feeder 20,
Further, the intermediate plate 45 does not receive the lifting rotation force by the pressing lever 46 until just before the cassette 40 is sufficiently pushed into the feeder 20 and is properly mounted. As shown in FIG. 12, the stacking sheet material P on the intermediate plate 45 is held in the cassette body case 41 in a horizontal posture. Therefore, in the process of pushing the cassette 40 into the feeder 20, the upper surface of the uppermost sheet material of the stored and stacked sheet material P in the cassette body case 40 is sufficiently separated downward from the downward facing circle 26a of the sheet material feeding roller 26. Therefore, there is no interference between the upper surface of the uppermost sheet material of the stacked sheet material P on the cassette 40 side and the feeding roller 26 on the feeder 20 side.

That is, the feeding roller 26 on the feeder 20 side is formed as a truncated circular roller, and the truncated circular side 26a is normally kept in a rotation angle posture in a downward direction so that the feeder top plate 21
The height dimension of the sheet material cassette storage space 23 formed by the lower surface of the table, the upper surface of the cradle c, and the inner surfaces of the left and right pedestals 21L and 21R can be increased.
It is possible to increase the sheet material storage capacity. Right and left end portions 47L and (47R) of the pressure shaft 47 protruding outward from the left and right side walls 41b and 41c of the cassette immediately before the cassette 40 is sufficiently pushed into the feeder 20 and is properly mounted. Left and right pedestals 21L and 21R of feeder 20, respectively
The left and right end portions 47 of the pressing shaft 47 are engaged by the cam grooves 33 provided on the inner surface side of the
L ・ (47R) receives downward pressure by the cam grooves 33 ・ 33,
The pressurizing shaft 47 descends from the end point on the upper end side to the end point on the lower end side along the slanting vertical slot 48 with which the pressurizing shaft 47 is engaged. With the downward movement of the pressure shaft 47, the pressure lever 46 is rotated clockwise about the support shaft 46a via the tension coil spring 49, and the horizontal arm 46b of the lever 46 is rotated in the rising direction. By the arm 46b, the middle plate 45 on which the sheet material P is loaded is lifted up on the front end side with the rear side portion 45a as a fulcrum, and is rotated in a forward inclined posture.

Then, when the cassette 40 is fully pushed in and moved, and when the cassette mounting is completed, the pressure shaft 47 reaches the lower end side end of the oblique vertical groove 48 with which the pressure shaft 47 is engaged, and the left and right ends 47L thereof.
・ (47R) is held by the lower ends 33a, 33a of the cam grooves 33, 33 and stopped.

On the other hand, the sheet material separating lever 50/50 has its extension 53/53.
Although the pressurizing shaft 47 that receives the downward motion descends along the groove hole 48 as described above, it rotates clockwise about the support shafts 51, 51 in the initial stage of its descending and pasting. The height regulating member 55 is provided on the upper surface portion of the sheet material near the tip side corners of the stacked sheet material P, which rises in reverse by the lifting rotation of the front edge side of the intermediate plate 45 accompanying the lowering of the pressure shaft 47.・
55 is received and further downward rotation is blocked, and the pressurizing shaft 47 is disconnected from the lever extension portions 53, 53 by the subsequent downward movement. Sheet material separating lever 50/50 is lever extension 53/53
Is attached to the stacked sheet material P by its own weight due to the edge of the pressure shaft 47 being cut off, and the setting state shown in the first illustration is obtained.

Thus, one of the sheet material feeding rollers 26 on the feeder 20 side
Each time the rotary drive is performed, the stacked storage sheet materials P in the cassette 40 mounted on the feeder 20 are separated and fed one by one according to the principle described in the first to fourth embodiments, and the conveying roller pair 28. 54, it is fed to the printer B side through the route of the entrance 19,
Image formation is sequentially performed on the fed sheet material.

As the consumption of the stacked and stored sheet materials P in the cassette 40 decreases, the intermediate plate 45 is sequentially lifted and rotated by the pressure lever 46 sequentially rotating clockwise by the charging force of the coil spring 49. To be done. As a result, the height level of the uppermost sheet material of the stacked sheet material P on the middle plate 45 on the leading edge side is
The sheet is pressed against the height regulating member 55 and is constantly maintained at a predetermined substantially constant level, so that the sheet material is separated and fed one sheet at a time.

(Effects of the Invention) As described above, according to the present invention, a special thick type such as a book card, a postcard, or an envelope in which it is impossible to separate and feed one sheet by forming a flexible loop on a sheet material by a separation claw type. It is possible to separate and feed one sheet material with a very simple structure, without requiring a large device such as a retard roller, and at the same cost as the conventional separating claw method, a thick special sheet material Feeding is possible, and there is no increase in the size of the device associated with feeding thick sheet materials.

For example, in an automatic feeding device that separates and feeds by a separating claw method, when the thick sheet material is fed, the shape of the tip of the separating claw is simply changed according to the present invention to obtain a conventional feeding device. It is possible to feed a thick sheet material with almost the same configuration.

[Brief description of drawings]

FIG. 1 is a perspective view of an essential part of the first embodiment device, FIG. 2 is a perspective view of a sheet material separating lever, FIG. 3 is a side view of an essential part of the lever, and FIG. b) and (c) are process diagrams for separating and feeding one sheet material, FIG. 5 is a perspective view of the sheet material separating lever of the second embodiment device, and FIGS. 6 (a), (b), and (c). )
Is a process diagram of separating and feeding one sheet material of the third embodiment device,
FIG. 7 is a diagram of a main part of the fourth embodiment device, and FIG. 8 is a vertical sectional side view of a sheet material feeding device as a fifth embodiment device and a laser beam printer combined therewith. Figure / No.
FIG. 10 is a front view and a vertical sectional view of the feeder of the sheet material feeding device, FIGS. 11 and 12 are a left side view and a vertical sectional view of the sheet material cassette, and FIG. 13 is a conventional separation claw method. It is a perspective view of the principal part of an example of a sheet material feeding device. A is a sheet material feeding device, B is a printer as the main body of the apparatus, 20 is a feeder, 26 is a feeding roller, 40 is a sheet material cassette, 45 is a sheet material stacking platform, 55 is a height regulation unit (first regulation). Part), 56 is a front end regulation member (first regulation part), and P is a stacked sheet material.

Claims (5)

(57) [Claims] 1. A feeding means for contacting an uppermost portion of a sheet material stack to give a feeding force to a sheet material, and a sheet material stack body feeding direction for contacting a front end face of the sheet material stack in a sheet material feeding direction. To the uppermost part of the sheet material stack, and a second restriction part that regulates the vertical direction of the sheet material stack. A gap α in the sheet material advancing direction exists between the uppermost portion of the material passing surface and the sheet material stack contacting surface of the second restriction portion, and the gap α is equal to that of one sheet material of the sheet material stack. Less than the thickness, between the uppermost sheet material passage surface of the first restriction portion and the sheet material stack contact surface of the second restriction portion, there is a gap β perpendicular to the sheet material traveling direction, The sheet material is separated by passing over the first restriction portion and passing through the gap β, The sheet material feeding device, wherein the regulation portion and the second regulation portion are swingably supported in the sheet material stacking direction. 2. The sheet material feeding device according to claim 1, wherein an upper portion of the first restricting portion is inclined forward as it goes upward. 3. The sheet material feeding device according to claim 1, wherein the second regulating portion regulates the sheet material depositing body in the up-down direction behind the front end portion in the feeding direction of the sheet material depositing body. Sending device. 4. The sheet material feeding apparatus according to claim 1, wherein the gap β is set in a range of 2 to 10 mm. 5. The friction coefficient of a slope portion of the front inclined surface of the first restriction portion, with which the tip of the uppermost sheet material of the sheet material stack abuts, is μ1, and the lower sheet than the uppermost sheet material. The friction coefficient of the slope where the tip of the material abuts is μ
3. The sheet material feeding device according to claim 2, wherein the relationship of .mu.1 <.mu.2 is satisfied when 2.