JPS6143255B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a sheet feeding device, and particularly to a sheet feeding device suitable for facsimile machines and the like.

Broadly speaking, there are two methods for feeding sheets, for example, transmission originals, one by one into the reading section of a facsimile machine. One method is for an operator to insert documents one by one into the document feed port. Another method is to stack a stack of originals with the front and back sides and top and bottom aligned on a sheet stacking table, and use an appropriate feeding means such as an air suction method or a roller method to move the originals to the topmost layer. Alternatively, there is an automatic feeding method in which the documents are separated and fed one by one starting from the lowest document.

In the former case, the operator is required to be present during the facsimile transmission operation, which is inefficient, but on the other hand, documents can be reliably fed one by one. In the latter case, automatic feeding is convenient, but in the case of such an apparatus, means to prevent double feeding of the document must be taken. In general, manuscripts vary in size, paper quality, etc., and may be charged with static electricity due to friction or the like. When such documents are stacked and automatically fed, a so-called separation error, in which a plurality of documents are fed in close contact with each other, tends to occur.

Therefore, in the case of an automatic feeder, the number of originals is checked before the transmission operation, and after the transmission, the number of originals is checked against the number of originals actually transmitted. If there is a document that is not sent due to a separation error, it is necessary to find the document and send it again, resulting in a troublesome post-processing work.

Additionally, various types of devices have already been proposed to ensure paper separation and feeding, but their effects are not as good despite their complex configurations, and in order to improve the separation effect, However, many of them have the disadvantage of damaging the original or smearing it by rubbing.

The present invention has been made in view of the above, and includes:
To provide a sheet feeding device that eliminates sheet separation errors and reliably feeds sheets one by one.

SUMMARY OF THE INVENTION An object of the present invention is to provide a sheet mounting table, a belt that is wound around at least a pair of pulleys so as to be rotatable in the forward and reverse directions, and has one of its extending portions positioned on the sheet placing surface of the sheet placing table; A plurality of sheet gripping claws having a closing habit and gripping the sheet are provided on the belt at a constant pitch, and a first driving means for moving the belt at the pitch in a direction opposite to the sheet feeding direction. a second drive means for moving the belt in the sheet feeding direction at the pitch; a feeding roller disposed above the pulley on the feeding side of the pair of pulleys; and a feeding roller on the feeding side. This is achieved by a sheet feeding device including a sheet guide means disposed near the pulley for removing the sheet from the sheet gripping pawl.

According to the sheet feeding device of the present invention, first, one sheet is held in one sheet holding claw while the belt is reversed in the opposite direction to the sheet feeding direction, and then this belt is held in one sheet holding claw. The sheets are fed by moving them in the sheet feeding direction, in other words, the sheets to be fed are held one by one in advance by sheet holding claws provided at a constant pitch, and Since the belt travels a distance corresponding to the pitch, the sheets being fed are reliably fed one by one to the facsimile machine, regardless of the type (thickness or thinness, strength of the waist, attached original, etc.). .

According to a detailed feature of the present invention, the sheet gripping claw has a closing habit when the belt is stretched between a pair of pulleys, but has a closing habit when the belt is wrapped around the pulley. By configuring this to open in the tangential direction and attaching and detaching the sheet to and from the belt at the winding part, an opening/closing mechanism for the sheet gripping pawl is not required, so that a sheet feeding device with a simple configuration can be provided.

Hereinafter, the present invention will be explained in detail with reference to illustrated embodiments.

FIG. 1 shows the mutual positional relationship between the main body of the facsimile device and the device of the present invention. In the figure, reference numeral 1 indicates a casing of the main body of the facsimile machine, and inside the casing 1, a reading section 5 consisting of two pairs of rollers 2 and 3 and a reading head 4 is provided at a predetermined interval. ing.

A sheet feeding device 6 is provided on the right side of the reading section 5, and a sheet, such as a transmission document, is fed from this sheet feeding device to the reading section. The sheet feeding device 6 is wound around a sheet loading table 7 on which a transmission document S (see FIG. 2) is placed, and a pair of belt pulleys 8, 9, and is substantially endless. A belt 10 in which the path portion 10a is positioned substantially on the same plane as the sheet loading surface of the sheet loading table 7, and a plurality of sheet gripping claws 11 (details) provided on the belt 10 at a constant pitch and having a closing habit. (to be described later), a feeding roller 12 disposed above the belt pulley 8, and a driving means to be described later. The above belt 10
In the illustrated embodiment, as shown in FIG.
It is disposed close to a side plate 7a provided on one side of the sheet mounting table 7 and serving as a reference for document feeding.

The setting of the transmission document on the sheet mounting table 7 and the subsequent feeding thereof are as follows.

Although the details will be described later, the sheet gripping claw 11 is
The belt 10 is opened at the part where it wraps around the pulley 8, and with this claw open, the leading edge of the document S to be sent is inserted between the claw and the belt 10, and then the belt 10 is held in the sheet's mouth. Move the holding claw clockwise by the pitch of the holding claw, and then attach the next sheet holding claw 1.
Let 1 hold the transmitted document in its mouth. Therefore, each time the transmission original S is set on the sheet mounting table 7, it is moved backward in the opposite direction to the paper feeding direction a, and is successively stacked on top of it. When the setting of the original to be transmitted is completed, as shown in FIG.
There is a transmission document S held and stacked in the holder.

After that, when a feed start button (not shown) is pressed, the belt 10 moves in the sheet feeding direction (counterclockwise in the figure) at the pitch, and at the same time the feeding roller 1
2 rotates in the direction of the arrow and sends out the first transmission document toward the reading section 5. The above-mentioned belt 1
0 moves by one pitch again to send out the next document, and this operation will be repeated from now on.

An example of a specific configuration of the apparatus of the present invention which performs the above-mentioned functions will be described with reference to FIGS. 3 to 10.

In FIGS. 3 to 5, belt pulley 8
is fixed to a support shaft 14 rotatably supported on the frame 13. On the other hand, belt pulley 9
is rotatably supported by a support shaft 15 fixed to the frame 13. Both pulleys 8 and 9 have
A belt 10 consisting of an endless timing belt is wound around the belt 10 with an appropriate tension applied thereto.

The belt 10 has a plurality of sheet gripping claws 11.
is fixed. The sheet gripping claw 11 is formed of an elastic thin plate, and the bent portion 11a formed at its base end is wrapped around the trough of the belt 10 to clamp and fix the belt (see FIG. 9). .
The sheet gripping claws 11 are provided for each trough of the belt 10, and are provided over a length that is approximately equal to the length of the stretched portion of the belt 10, in the illustrated case, the stretched side. Further, the free end 11b of the sheet gripping claw 11 is bent toward the belt surface, and is pressed against the belt surface or the back of an adjacent claw by its own elasticity. In order to ensure the sheet clamping action of the sheet gripping claw, the free end 11b may be coated with a high friction member 11c such as rubber, and furthermore, a rubber 11d may be sprayed on the back surface where the free end comes into pressure contact. , the clamping becomes more secure (see Fig. 11).

The closing habit of the sheet gripping claw 11 is as follows:
1, and in the part where the belt 11 is wound around the pulley, the belt 11 bends and opens approximately in the tangential direction (Figs. 3 and 10). reference).

The circumferential surfaces of the pulleys 8 and 9 are formed in complementary shapes corresponding to the peaks and valleys of the timing belt, and the peaks have bent portions of the sheet gripping claws 11. A recessed portion (only the pulley 9 is shown with reference numeral 9a in FIGS. 3 and 4) into which the portion 11a enters is provided.

A ratchet wheel 16 of the same pitch as the timing belt is fixed to the center of the support shaft 14, and an operating lever 17 is rotatably supported at the outer shaft end of the frame 13.

The actuation lever 17 has a first arm 17a and a second arm 17.
A cam follower 18 that abuts against a cam 33, which will be described later, is attached to the first arm 17a. The ratchet wheel 1 is attached to the tip of the second arm 17b.
A support shaft 19 is fixedly planted toward 6. The support shaft 19 enters through the window hole 13a (see FIG. 4) of the frame 13, and the feed claw element 2
0 is rotatably supported.

The feed pawl element 20 is located close to the outer periphery of the ratchet wheel 16, and is formed with two pawls 21, 22 that selectively engage with the ratchet wheel 16. One claw 21 engages with the ratchet wheel 16 when the belt 10 is rotated in the opposite direction to the sheet feeding direction, and the other claw 22 engages with the ratchet wheel 16 when the belt 10 is rotated in the sheet feeding direction. 16.

A pin 23 is fixed to the feed claw element 20 in parallel with the support shaft 19. On the other hand, the second arm 17b of the operating lever 17 is provided with a long hole 24 into which the pin 23 enters.

The frame 13 also includes the feed claw element 20.
A switching member 25 for switching the mode is provided diagonally. This switching member 25 has a long hole 25b having a locking protrusion 25a that is loosely fitted into a piece 27 fixed to the frame 13 with a headed screw 26, and a lower long groove 25c that is connected to a guide pin 28 fixed to the frame 13. It is loosely fitted into the frame 13, and is slidable along the frame 13 within the range of the elongated hole 25b. One end of a helical spring 29 whose other end is locked to a stationary member is locked to one side of the switching member 25, giving the switching member 25 a tendency to move downward.

Furthermore, approximately in the center of the switching member 25, there is formed a notch 25d into which the support shaft 19 enters, and a part of this notch 25d, which abuts against the pin 23 of the feed claw element 20. An engaging portion 30 and a bent portion 25e provided at the upper end of the member are respectively formed.

Between the bent portion 25e and the pin 23,
A hanging spring 31 is stretched across it. Due to the elasticity of the spring 31, the pin 23 is brought into pressure contact with the engaging portion 30 of the switching member 25 (see FIG. 5).

In the document setting mode shown in FIG. 5, the switching member 25 is moved by the elasticity of the spring 29 to the lowest position where the top 27 is located at the upper end of the elongated hole 25b. In this mode,
The feed pawl element 20 swings clockwise about the support shaft 19 by pushing the pin 23 with the engaging portion 30, and moves one pawl 21 between the teeth of the ratchet wheel 16. It is in contact with one. Further, in the above mode, the operating lever 17 is pushed by the lower edge of the elongated hole 24 by the pin 23, and the supporting shaft 14
It is oscillated counterclockwise around the center.

A feeding roller 12 is disposed above the pulley 8 and is made of relatively hard sponge rubber and has a cutout portion 12a with a portion of its circumferential surface removed. This feeding roller 12 is connected to the frame 1.
The drive shaft 32 is rotatably supported between the drive shaft 3 and the other frame (not shown).

A cam 33 is fixed to one end of the drive shaft 32, with which the cam follower 18 of the operating lever 17 comes into contact, and a drive motor 35 is attached to the other end via a one-turn clutch 34, as shown only in FIG. are connected. The feed roller 12 and cam 33 are in their home position as shown in FIG. 5, and this position is held by the one-turn clutch 34.
The drive motor 35 has a feed start button (not shown).
This rotation is caused by the rotation of the drive shaft 3 intermittently according to the operation of the one-turn clutch 34.
2. The belt 10 is moved in the sheet feeding direction a.
(See FIG. 2) The second driving means for moving the belt at a constant pitch includes a pulley 8 around which the belt 10 is wound, a ratchet wheel 16 that is substantially integral with the pulley, and a feed pawl element 20 that rotates the ratchet wheel. An actuation lever 17 that rotates this feed claw element, a pin 23 that connects this lever and the feed claw element, a cam follower 18 provided on the actuation lever, a cam 33 that this cam follower comes into contact with, a drive shaft 32 that rotates this cam, It consists of a drive motor 35 that drives this shaft via a one-turn clutch 34.

In the feeding mode, the switching member 25
It is positioned as shown in FIG. That is, when the switching member 25 is moved upward against the elastic force of the spring 29 while holding the bent portion 25e, the member swings counterclockwise about the pin 28. Therefore, the piece 27 moves relatively to the right in the wide part of the lower end of the elongated hole 25b, and the protrusion 27a of the piece is located below the locking part 25a. When the hand is subsequently released, the locking portion 25a and the protrusion 27a engage to hold the switching member 25 in the feeding mode position shown in FIG.

In this feeding mode, the feeding claw element 20
By being pulled by the spring 31, the pin 23 swings counterclockwise about the support shaft 19, causing the pawl 22 to engage with the pawl of the ratchet wheel 16. Further, the actuating lever 17 is swung clockwise by the pin 23 engaging with the upper edge of the elongated hole 24, and the cam follower 18 is moved to the cam 33 at the home position.
It is in contact with the The first driving means for moving the belt 10 at a constant pitch in a direction opposite to the sheet feeding direction a (see FIG. 2) includes a pulley 8 around which the belt 10 is wound, and a ratchet wheel 16 that is substantially integrated with the pulley.
It is mainly composed of a feed pawl element 20 that rotates this ratchet wheel, and an operating lever 17 that reciprocates this feed pawl element around the ratchet wheel.

Also, near the pulley 8, as shown in FIGS. 4, 9, and 10, a sheet guide means 36 is provided.
is installed.

The sheet guide means 36 is provided on the sheet feeding side of the pulley 8, and is arranged on the sheet loading table 7 in such a manner that the pulley 8 is sandwiched between the bent free ends 37a of the two prongs.
a sheet removal claw 37 fixed to the front end 7b of the
It consists of a guide plate 38 made of an elastic plate, the free end 38a of which is positioned so as to intersect the free end 37a of the sheet removing claw 37, and the guide plate 38 is inclined in the sheet feeding direction. The guide plate 38 is supported by a support 39 fixed to the frame 13.

The free ends of the sheet removing claw 37 and the guide plate 38 intersect at approximately the same position as the sheet gripping claw 11 which is open directly below the feeding roller 12. Further, the notch 37b provided in the sheet removing pawl 37 is for escaping the sheet gripping pawl 11, and the notch 38b provided in the guide plate 38 is for escaping the sheet gripping pawl 11 and the feeding roller 12. be.

Further, a cam plate 39 is rotatably supported on the support shaft 14 of the pulley 8, as shown in FIG. A stopper 39a is formed in a part of this cam plate 39. A stopper 40 is pivotally supported on the support shaft 15 of the pulley 9, and both stoppers 39a,
40 are connected by a wire 41. Free ends of both stoppers 39a, 40 are bent toward the belt.

On the other hand, a release claw 42 is fixedly provided on the underpass portion 10b of the belt 10. In the document setting mode, which will be described later, the release claw 42 moves to the left in FIG. moves to the right and collides with the stopper 40, and swings the cam plate 39 via the wire 41 to release the engagement between the claw 22 and the ratchet wheel 16. Therefore, the release claw 4
2, the belt 10 reciprocates over a distance corresponding to the length of the spanning portion between the pulleys 8 and 9. The driving of the belt 10 will be described later. Further, as shown in FIG. 6, the ratchet wheel 16 is elastically engaged with a click stopper consisting of a roller 45 pivotally attached to one end of a lever 44 biased by a spring 43.

Now, the operation of the apparatus of the present invention constructed as described above will be explained below by dividing it into two modes: the transmission document setting mode and the feeding mode.

Transmission original setting mode In this mode, the transmission original is held in the sheet gripping claw while the belt is reversed.

In this mode, the switching member 25 is placed in a position where the top 27 and the locking portion 25a are disengaged, as shown in FIG. At this time, power to the drive motor 35 is cut off. Also,
In this mode, all sheet gripping claws 1
1 is located to the left from directly below the feeding roller 12, in other words, in a portion of the belt 10 extending from the portion where it wraps around the pulley 8 to the underpass portion. However, in FIG. 5, for convenience of illustration, the two sheet gripping claws are located to the right of just below the feeding roller.

As shown in FIG. 5, the sheet gripping claw 11 directly below the feeding roller 12 is open. With respect to this open sheet gripping claw 11, the operator:
First, insert the document to be sent last.

This document insertion will be explained in detail with reference to FIG. 10. The belt 10 is placed on approximately the same surface as the sheet placing table 7 (in FIG. 10, for convenience of illustration, the belt and the sheet placing table 7 are spaced apart from each other). ), and this belt 1
Since the guide plate 38 is provided obliquely in a direction that intersects with the belt 10, the operator inserts the document S between the belt 10 and the guide plate 38.

At this time, the free end 38a of the guide plate 38 is located closer to the belt than the open free end 11a of the sheet gripping claw 11, so the leading edge of the inserted original is between the sheet gripping claw 11 and the belt 1. It will penetrate between the surface and the surface. The position where the leading edge of the document abuts the sheet gripping claw 11 and the sheet removal plate 37 is the limit for document insertion.

When the document insertion is finished, move the operating lever 17 to the fifth position.
It is swung from the position shown in the figure to the position shown in FIG. That is, when the actuating lever 17 is moved clockwise around the support shaft 14, the cam follower 18 is moved toward the cam 3.
3, the second arm 17b
The feed pawl element 20 pivotally attached to the tip of the feed pawl element 20 is rotated clockwise, and at this time, the pawl 21 engaged with the ratchet wheel 16 rotates the ratchet wheel 16 by one pitch clockwise.

As the ratchet wheel 16 rotates, the ratchet wheel and the pulley 8 (sixth
(not shown in the figure) rotates clockwise. The rotation angle of this pulley 8 is the same as the arrangement pitch of the sheet gripping pawl 11, so the sheet gripping pawl that was open at the wrapping part until now is
As the belt 10 rotates, it is moved to the stretching section of the belt 10 and closed. As the sheet gripping pawl 11 moves, the document inserted into the pawl is also moved by the same pitch, and its leading edge is clamped between the sheet gripping pawl and the surface of the belt 10.

The actuating lever 17 is connected to the spring 29 of the switching member 25.
Due to the elasticity of the slider, it swings back from the position shown in FIG. 6 to the position shown in FIG. At this time, the pawl 21 of the feed pawl element 20 passes over one tooth of the ratchet wheel 16. In this way, the ratchet wheel 16 is rotated by one pitch by the swinging of the operating lever 17, and the belt 10 is rotated along with this, thereby opening and closing the sheet gripping pawl 11. Then, the document is held in the sheet holding claws 11 which are open at the part where the belt 10 is wrapped. Therefore, as shown in FIG. 2, on the sheet mounting table 7, the transmission document whose leading edge is clamped by the sheet gripping claw 11 is placed with the leading edge shifted by the arrangement pitch of the sheet gripping claw. They will be stacked in the order of transmission from the top.

By repeating the above operations, when the insertion of the document into the last sheet holding claw 11 is completed, the release claw 42 (see FIG. 3) engages with the stopper 39a. Then, when the operating lever 17 is swung from the position shown in FIG. 5 to the position shown in FIG.
The pawl 21 rotates the ratchet wheel 16 and moves the belt 10 in the opposite direction to the sheet feeding direction.At this time, the release pawl 42 rotates the cam plate 39 clockwise around the support shaft 14 via the stopper 39a. Rotate in the direction. The rotational position of the cam plate 39 is held by a release claw 42 provided on the belt 10. The pushed cam plate 39 moves its cam edge to the ratchet wheel 16 within the movement range of the pawl 21.
Position it outside the tip circle of the tooth. Therefore, at this time, the end 21a of the claw 21 (see FIG. 3) rides on the cam plate 39.

That is, by rotating the cam plate 39, the claw 2
1 and the ratchet wheel 16 are disengaged. After this, even if the operating lever 17 is swung, the pawl 21 and the ratchet wheel 16 do not engage with each other, so the belt 1
No rotational driving force to 0 is transmitted.

In addition, as already explained, the sheet gripping claw 1
1 is closed only at the stretch portion of the belt 10, so the timing for disabling the action of the feed claw element 20 is when the sheet gripping claw that clamped the original document is still located in the straight portion of the overpass portion. It is when If this is not done, the sheet gripping claws will open at the part where the belt wraps around the pulley 9, releasing the document clamp or damaging the leading edge of the document.

This completes the setting of the original to be sent.

Feeding Mode This mode is a mode in which a transmission original stacked on a sheet mounting table with its leading edge clamped is fed to the reading section 5 of the facsimile apparatus (see FIG. 1). Switching from the transmission document set mode to this paper feeding mode is performed by moving the switching member 25 from the position shown in FIG. 5 to the position shown in FIG. 7.

That is, as shown in FIG.
5 is moved upward against the elasticity of the spring 29, and the locking portion 25a and the protrusion 27a of the top 27 are engaged to hold this position. Switching member 2
5 causes the spring 31 to move the feed pawl element 20
, the actuating lever 17 is swung clockwise about the support shaft 14 until the cam follower 18 abuts against the cam 33.

Also, at this time, the feed claw element 20
Since the claw 3 is pulled by the spring 31, it is rotated counterclockwise around the support shaft 19, and the claw 2
2 is engaged with one pawl of the ratchet wheel 16.

In the state shown in FIG. 7, when the feeding start button (not shown) is pressed, the drive motor 35 and the one-rotation electromagnetic clutch 34 are energized, and the rotation of the motor 35 is transmitted via the clutch 34 to the drive shaft 32.
transmitted to.

As the drive shaft 32 rotates, the feeding roller 12 and the cam 33 rotate clockwise. As the cam 33 rotates, the operating lever 17, which is in contact with the cam 33 via the cam follower 18, is pushed counterclockwise from the position shown in FIG. 7 to the position shown in FIG. This swinging of the operating lever 17 is
A pin 23 that is made to resist the elasticity of the spring 31 and that locks one end of the spring 31;
In other words, the feed pawl element 20 is rotated counterclockwise about the support shaft 19 and at the same time revolves around the support shaft 14 . Therefore, the pawl 22 rotates the pawl wheel 16 by one pitch,
The belt 10 is moved in the sheet feeding direction (to the left in FIG. 8) by the pitch of the sheet gripping pawls via the pulley 8 which is substantially integrated with the ratchet wheel.

The cam 33 rotates once by the operation of the one-turn electromagnetic clutch 34, and then stops at the home position shown in FIG. The operating lever 17 is moved from the position shown in FIG.
When it rotates to the position shown in the figure, it comes into contact with the cam edge due to the elasticity of the spring 31, and accordingly swings back clockwise. At this time, the feed pawl element 20 is also moved so that the pawl 22 passes over one tooth of the pawl wheel 16. Also, at this time, the ratchet wheel 16
is prevented from rotating by a click stopper (see Figure 6). By the way, Cam 33
During one rotation, the actuating lever 17 makes one reciprocating motion to feed the belt 10 one pitch.

Incidentally, when the cam 33 rotates once, the feed roller 12 also rotates once, and the feed roller 12 is separated from the sheet gripping claw 11 in the home position shown in FIG. The distance between the feeding roller 12 and the sheet gripping claw 11 is maintained while the sheet gripping claw 11 moves one pitch. In other words, when the cam 33 rotates from the position shown in FIG. 7 to the position shown in FIG. There is. When the defective portion 12a of the feeding roller 12 faces the sheet gripping claw 11, there is no contact between the circumferential surface of the roller and the document to be transmitted. When rotating to the position, the regular roller peripheral surface portion 12b comes into contact with the document.

Sheet gripping claw 11 that clamps the transmission document
However, when the document is opened at the part where the belt is wrapped around the pulley 8, the pressing force of the gripping claw on the leading edge of the document is released.
As shown in FIG. 1, since the sheet removing claw 37 is arranged, the original to be transmitted, which has been moved while being clamped by the sheet gripping claw 11, has its leading edge moved to the free end 37a of the sheet removing claw 37. It collides with and stops (see symbol SA in Figure 11).
The tip of the sheet gripping claw 11 is then extracted from the sheet gripping claw 11, which continues to rotate.

In reality, the stopping time of the transmitted document after the clamp is released is extremely short; by the time the document comes off the grip, it has already rotated as shown by the chain line in FIG. The original conveying action by the regular roller peripheral surface portion 12b continues.

That is, the leading edge of the document pulled out from the sheet gripping claw is brought into contact with the pair of free ends 37a, 37a of the sheet removal claw 37, but at this time, part of the bottom surface of the document is The sheet gripping claw (indicated by reference numeral 11A in FIGS. 9 and 11, which is still clamping the next document) that is about to open comes into contact with the back surface and is pushed upward. Then, the regular roller peripheral surface 12bA (the first
Since the upper surface of the document is pressed against the reference numeral 12b) in FIG. 1, the leading edge of the document is held between the feeding roller 12, the free end 37a of the sheet removal claw 37, and the back surface of the sheet gripping claw 11A. (See Figure 11). At this time, the claw that was holding the sheet in its mouth is located below the sheet removal claw. Therefore, due to the friction of the peripheral surface 12b of the rotating feeding roller 12, the document is
As indicated by the symbol SB in the figure, it is sent out toward the reading section 5 (see FIG. 1). When the document clamp is released, the guide plate 38 is moved to the 11th position by the document pushed up by the sheet gripping claw 11A.
It is deflected as shown in the figure.

The document feeding length by the feeding roller 12 is determined by the effective circumference of the portion 12b of the roller other than the missing portion 12a, and this length is determined by the fact that the leading edge of the fed document is the roller pair 2 (the first (see figure)
It has become enough to be held in high esteem.

Then, the electromagnetic clutch 3 rotates once in response to a reading end signal from the reading section 5 or a signal from a document detecting means provided in the middle of the document conveyance path.
4 is energized, the cam 33 rotates once again clockwise from the position shown in FIG. 7 and stops.
During this time, the operating lever 17 is swung to move the belt 10 by one pitch in the sheet feeding direction and send out the next document.

The same action is repeated thereafter, but when the last transmission document (the first document clamped) is fed, the release claw 42 shown in FIG. 3 engages with the stopper 40 and The cam plate 39 is rotated counterclockwise via the wire 41. Due to this rotation, the cam plate 39
The cam edge is positioned outside the tip circle of the ratchet wheel 16 within the range of movement of the pawl 22, and the engagement between the pawl 22 and the ratchet wheel 16 is released.

Therefore, after this, one rotation electromagnetic clutch 34
acts, the cam 33 rotates, and the actuating lever 1
7 swings, the ratchet wheel 16 is not rotated, and the belt 10 is also not rotated. In the reading section 5, if the next document is not fed in after a certain period of time, the power to the drive motor 35 is cut off.

With this, the feeding mode ends.

Although the present invention has been described above based on specific embodiments, the present invention is not limited thereto, and various modifications can be made within the scope of the technical idea of the present invention.

For example, in the illustrated embodiment, the first driving means for rotating the belt 10 in the reverse direction in the transmission document setting mode and the second driving means for rotating the belt 10 in the normal direction in the feeding mode are connected to a ratchet wheel 16, an operating lever 17, a feeding pawl element, and the like. 20. Although the switching member 25 is used as a common component, they may be separate, and the belt 10 may be driven using the pulley 9. Also, the first
The belt 10 may be reversely rotated by rotating the pulley 9 using a driving means. In the illustrated embodiment, the sheet gripping claws are fixed to an endless belt, but the sheet gripping claws may be provided so as to move back and forth without being formed endlessly.Furthermore, a chain may be used instead of a belt. Of course.

Furthermore, in the transmission document setting mode, in the illustrated embodiment, after inserting the leading edge of the document into the open sheet gripping claw, the actuating lever is manually swung to move the belt 10 backward. The insertion of a document into the claw is detected by a micro switch or a photoelectric switch, and a solenoid is connected to the operating lever 17, and the detection signal from the switch operates the solenoid to reverse the ratchet wheel 16. It may also be possible to move it backwards.

Furthermore, regarding the placement position of the belt 10 with respect to the sheet placement table 7, as shown in FIG. Even if the document skews due to backward movement in the feed mode, the reference side edge of the document naturally follows the side plate 7a and is corrected to the correct posture in the feed mode. Of course, it may be provided at the center in the direction, or may be provided on both sides of the sheet mounting table.
In particular, if belts are provided on both sides of the sheet loading table and the belt is used as a feeding device for feeding large-sized paper in a diazo copying machine, reliable feeding becomes possible.

[Brief explanation of the drawing]

Fig. 1 is a side view showing an example in which the device of the present invention is applied to a facsimile machine, Fig. 2 is a schematic plan view showing an embodiment of the invention, and Fig. 3 is an exploded view of essential parts of an embodiment of the invention. A perspective view, FIG. 4 is a plan view of the same, FIG. 5 is a side view showing the transmission document setting mode, FIG. 6 is a view of the same operation, FIG. 7 is a side view of the same operation. 9 are perspective views showing an example of the sheet guide means, and FIGS. 10 and 11 are side views illustrating the mutual positional relationship and operation of the transmission original, the sheet gripping claw, and the feeding roller. . 7... Sheet mounting table, 8, 9... Pulley, 10
... Belt, 11 ... Sheet grip claw, 12 ... Feeding roller, 16 ... Ratchet wheel, 17 ... Operating lever, 2
0...Feeding claw element, 21, 22...Claw, 25...
Switching member, 33... cam, 34... one-way electromagnetic clutch, 35... drive motor.

Claims (1)

[Scope of Claims] 1. A sheet mounting table 7 and at least a pair of pulleys 8 and 9, which are wound around the sheet mounting table 7 and at least a pair of pulleys 8 and 9 so as to be rotatable in the forward and reverse directions, and one of the extending portions 10a
a belt 10 positioned on the sheet loading surface of the sheet loading table 7; a plurality of sheet gripping claws 11 having a closing habit provided on the belt 10 at a constant pitch; First driving means 8, 1 for moving in the direction opposite to a at the pitch mentioned above.
6, 17, 20, and a second driving means 8, 16, 17 for moving the belt 10 in the sheet feeding direction a at the pitch.
18, 20, 23, 32, 33, 34, 35; Of the pair of pulleys 8, 9, a feeding roller 12 disposed above the pulley 8 located on the feeding side; and a feeding roller 12 on the feeding side. A sheet feeding device comprising a sheet guide means 36 disposed near the pulley 8 and for removing the sheet S from the sheet gripping claw 11.