JPH0825657B2 - Sheet material separating and feeding device - Google Patents

Description

Description: (a) Field of Industrial Application The present invention relates to a sheet feeding / separating apparatus, and more specifically, a large number of sheets in a stacked state in an electronic copying machine, a facsimile, an image reading apparatus or the like. Sheet automatic document feeder for automatically feeding the document sheets one by one to the document illuminating section and the document reading section, or a large number of copy sheets and printing sheets which are also stacked in an electronic copying machine or a printing machine. The present invention relates to a sheet material separating / feeding device such as a transfer paper automatic feeding device for automatically feeding sheets one by one to a transfer unit or the like.

(B) Conventional Technology Conventionally, as a sheet material separating / feeding device of this type,
Conveying roller 1 rotating in the conveying direction of the sheet material P shown in the figure
And a separation pad 2 are in contact with each other, and a friction roller system in which the conveyance roller 1 rotating in the conveyance direction of the sheet material P shown in FIG. 7 is composed of a pair of upper and lower endless belts 5 and 6 which are in contact with each other as shown in FIG. 7, the upper belt 5 is driven to run in the conveying direction of the sheet material P, and the lower belt 6 is stopped or run in the opposite direction. Driven friction belt type and 8th-10th
A plurality of narrow endless belts alternately arranged in the upper and lower direction shown in the figure
A belt using the waist strength of the sheet material P that is composed of 7, 9 and that drives the belts 7 above it in the conveying direction of the sheet material P and drives the belts 9 below to stop or drive in the opposite direction. There is a separation type. In each of the above figures, reference numeral 10 indicates a pair of conveying rollers, reference numeral 11 indicates a pickup roller, and reference numerals 12, 15 and 13, 16 respectively indicate a driving pulley and a driven pulley. Is.

However, in any of the above methods, the sheet material P is separated by the separating members such as the separation pad 2, the separation roller 3, and the separation belts 6 and 9, and the conveyance roller 1 and the conveyance belts 5 and 7 are separated.
Since the separating member is stopped or is rotated or driven in the opposite direction by the time the sheet is fed forward by the conveying member such as the above, as shown in FIG. The sheet material P may be bent or broken due to the collision with the separating member, and as a result, the sheet material P cannot move toward a contact point or a meeting point between the conveying member and the separating member, that is, toward the nip portion. There is a drawback that the sheet material P cannot be separated and fed. This drawback is
In particular, the damaged sheet material P is apt to appear remarkably, which is the greatest weak point of this type of sheet material separating and feeding system utilizing the frictional action.

Therefore, in order to eliminate the above-mentioned drawbacks, recently, as shown in FIG. 12, a thin plate-shaped member is formed so as to be as close as possible to the contact portion between the conveying roller 1 and the separating roller 3 which is in pressure contact with the conveying roller 1. A low friction member 17 is provided and configured so as to avoid the above-mentioned collision between the sheet material P and the separating roller 3 by the guide action of the low friction member 17, or as shown in FIG. And the separating roller 3 are pressed against each other so as to rotate the conveying roller 1 in the conveying direction of the sheet material P, and the separating roller 3 has a torque limiter 19 and a transmission mechanism having a structure as shown in FIG. When the sheet material P does not exist between the conveying roller 1 and the separating roller 3 as shown in FIG. Force the sheet material P in the conveying direction When the plural sheet materials P ₁ , P ₂ are sandwiched between the conveying roller 1 and the separating roller 3 (see FIG. 15),
As shown, the conveying roller 1 and the friction coefficient mu ₁ of the sheet P _1, the sheet material P _1, P ₂ the friction coefficient of comrades mu _3, and the coefficient of friction between the separation roller 3 and the sheet material P ₂ mu ₂ Between μ ₁ ＞
The mu _2> mu ₃ the relationship, the sheet P ₁ in contact with the conveying roller 1 is fed in the conveying direction, the sheet material P ₂ in contact with the separation roller 3 is reversed via the torque limiter 19, the transmission mechanism 20 When the separating roller 3 returns the sheet to the side opposite to the conveying direction to prevent double feeding (see FIG. 15), and when only one sheet material P is properly sandwiched between the conveying roller 1 and the separating roller 3, , As shown in FIG. 16, the friction coefficient μ
Due to the relation of ₁ > μ _2, the sheet material P is conveyed in the conveying direction by the conveying roller 1 and the separation roller 3 which is forcibly rotated in the conveying direction (see FIG. 15), and the sheet material P is conveyed to the above-mentioned sheet material P. Conveying roller 1 and separating roller 3
When a plurality of sheet materials P are again sandwiched between and, the sheet materials P other than the sheet material P contacting the conveying roller 1 are reversed by the separation roller 3 in the same manner as in the case of FIG. Has proposed to return to the side opposite to the conveying direction (see FIG. 15).

(C) Problems to be Solved by the Invention By the way, in the above-described one shown in FIG.
Is attached to the pressing contact portion between the conveying roller 1 and the separating roller 3, that is, a little front side of the nip portion, the sheet material P still bends due to the collision with the separating roller 3, resulting in low friction. If the effect of providing the member 17 cannot be expected, and conversely, if the low friction member 17 is mounted in such a state that it has entered the nip portion, the separation roller 3
However, there is a drawback in that it is technically extremely difficult to properly dispose the low friction member 17 close to the nip portion.

In the case of FIG. 13 described above, it is very difficult to set the relationship between the friction coefficients μ ₁ and μ ₂ between the conveying roller 1 and the separating roller 3 and the sheet material P, the separating pressure, and the operation setting torque of the torque limiter 19. Even if the proper value of the operation setting torque of the torque limiter 19 is experimentally obtained, it is not easy to actually produce a torque limiter having such an operation setting torque, and even if it is produced, the torque limiter 19 However, there is a drawback in that it is very difficult to maintain the initial value because the operation setting torque of the above changes with time.

Further, as shown in FIGS. 12 and 13, in a system in which the conveying roller 1 and the separating roller 3 are constantly in pressure contact with each other with a predetermined pressing force, as shown in FIG. There is a drawback that it is extremely difficult for the sheet material P to pass between the rollers 1 and 3 after passing through the section.
In the conventional separation and feeding method, including those shown in Figs. 2 and 13, a conveying member in a wedge portion composed of curved portions or straight portions which are in contact with each other, such as a roller pair roller, a belt pair roller, and a belt pair belt, Since the conveyance and separation of the sheet material P are determined by the unstable contact of the separating member with the sheet material P, there is a fundamental drawback that the conveyance and separation of the sheet material P is extremely unstable.

(D) Means for Solving the Problem The present invention aims to solve the above-mentioned problems, and a conveying member that rotates in a sheet material feeding direction and a sheet member that rotates in a direction opposite to the sheet material feeding direction. In addition, a sheet material detecting means is disposed downstream of the separating member that is displaceably contactable and separable with respect to the conveying member in the sheet material feeding direction, and is displaceably contactable and separable with the conveying member and feeding the sheet material. A feeding member that rotates in a direction in which the sheet material is not detected by the detecting means, the conveying member and the separating member are brought into a non-contact state, and at the same time, the conveying member and the feeding member are brought into a contact state, When the sheet material is detected by the detection means, the conveying member and the separating member are brought into contact with each other, and at the same time, the conveying member and the feeding member are brought into non-contact with each other.

(E) Operation By adopting the above means, when there is no sheet material between the conveying member and the separating member, the conveying member and the separating member are separated by a predetermined distance, and both the conveying member and the feeding member are sheet materials. Since the sheet material is rotated in the feeding direction, even if several sheet materials are conveyed in a state of being superposed by a pickup roller, those sheet materials are positively conveyed by the conveying member and the feeding member. . Then, these sheet materials pass through the gap between the conveying member and the separating member,
When any of these sheet materials is detected by the detection means, the feeding member is separated from the separating member, the conveying member and the feeding member are separated by a predetermined distance, and the separating member moves toward the conveying member and is conveyed. The member and the separating member come into contact with each other with a predetermined pressing force. Then, the sheet material contacting the conveying member is conveyed in the feeding direction by the conveying member due to the frictional contact force between the conveying member and the sheet material contacting the separating member is separated by the frictional contact force between the separating member. The sheet material returned by the member in the direction opposite to the feeding direction and finally left between the conveying member and the separating member has a frictional contact force between the conveying member and the sheet material, Based on the greater frictional contact force between
It is sent in the feeding direction. In this way, the stacked sheet materials are sequentially separated one by one and fed to the next work process or the like.

(F) Example Hereinafter, examples embodying the present invention will be described with reference to the drawings.

As shown in FIG. 1, the sheet-shaped document automatic feeding device 21 is configured to feed a sheet-shaped document P, which is placed on the document table 22 in a stacked state by a pick-up roller 23, to separate and feed the document sheet P. 25, and the original separating and feeding unit 25
The sheet-shaped originals P separated one by one are fed to the downstream original reading section and the like through the pair of conveying rollers 26.

As shown in detail in FIG. 2, the document separating / feeding unit 25 directs the sheet-shaped document P from the document placing table 22 side toward the conveying roller pair 26 side by a drive source (not shown) fixed to a shaft 27. A transport roller 29 which is rotated so as to feed, and the roller
The shaft 3 is placed opposite to the lower side of 29 by a drive source (not shown).
0, a drive side pulley 31 fixed to the shaft 30, a transmission belt 32 wound around the pulley 31, a driven side pulley 33 rotated by the belt 32, and a shaft to which the pulley 33 is fixed
A separating roller 36 which is rotated in the direction opposite to the feeding direction of the sheet-like document P via 35, and which is also arranged opposite to the lower side of the conveying roller 29 and is substantially parallel to both axial sides of the separating roller 36. It is equipped with the feed rollers 37, 37 located,
Both ends of the shaft 35 to which the separation roller 36 is fixed are respectively the shafts 30.
Is rotatably supported on one end side of lever members 39, 39 which can be swung about the feed rollers 37, 37, and the feed rollers 37, 37 can be swung about a fixed shaft 40, respectively. The lever members 41, 41 are rotatably supported by the shafts 42, 42 at one end side thereof.

Then, the lever members 39, 39 and another lever member 4
On the other end side of 1,41, respective lever members 39,39 and 41,41
The rod-shaped connecting members 43 and 45 are fixed so as to connect the connecting members, and the link members 46 and 46 are provided so as to connect the connecting member 43 and the connecting member 45. Further, a solenoid means 47 is disposed on one side of the coupling member 43, the plunger 49 of the solenoid means 47 and the coupling member 43 are coupled via a link spring 50, and the coupling member 45 is also provided.
On the other side of the
When the solenoid means 47 is excited, the plunger 49 is retracted against the tension spring 51, and the lever members 39, 39 are connected to the shaft 30 via the link spring 50.
And the separation roller 36 is brought into a non-contact state with the transport roller 29, and at the same time, via the connecting member 43, the link members 46, 46 and the connecting member 45, another lever member 41,
41 is also rotated counterclockwise about the shaft 40 so that the feed rollers 37, 37 are in contact with the conveying roller 29, and the plunger 49 is extended when the solenoid means 47 is not excited. Then, the lever member 39, 39 is rotated clockwise around the shaft 30 via the connecting member 45, the link members 46, 46 and the connecting member 43 by the spring force of the tension spring 51, and the separating roller 36 causes the conveying roller 29. To the lever member with a predetermined pressing force and via the connecting member 45.
41, 41 are also rotated clockwise about the shaft 40 so that the feed rollers 37, 37 are not in contact with the transport roller 29.

Further, as shown in FIG. 1, the conveying roller 29 and the separating roller 36 are located close to the front side (downstream side) of the sheet-shaped document P in the feeding direction, for example, by a photoelectric method, an ultrasonic method, or a contact method. A sheet-like document detection sensor 52 of an appropriate system or the like is provided, and the above-mentioned solenoid means 47 is de-energized by the detection action of the sheet-like document P by the sensor 52, and a solenoid means (not shown) The pickup roller 23 is separated upward from the sheet-like document P on the document table 22 by the excitation.

The above-described sheet-shaped document automatic feeding device 21 is incorporated in the document reading device 53 in a manner as shown in FIG.

In addition, what is denoted by reference numeral 55 below the document placing table 22 in FIG. 1 is rotated by a sheet-like document P placed on the document placing table 22 and presence / absence of a sheet-like document not shown. It is a sensor lever member that turns on the detection sensor.

Since the present embodiment is configured as described above, a large number of sheet-shaped originals P are placed on the original placing table 22 and the sensor lever member 55 is rotated, so that a sheet-like original presence / absence detection sensor (not shown) is provided. When the feeding of the original P is instructed in the on-operation state, the pickup roller 23 is lowered onto the laminated sheet-like original P and is rotationally operated so that the sheet-like original P is fed.
Feeding is started (see FIG. 4). Similarly, while the sheet-shaped original P is not fed between the conveying roller 29 and the separating roller 36, which are also started to rotate, the separating means 36 is in the excited state of the solenoid means 47.
Is separated from the transport roller 29 by a predetermined distance,
Since 37 is in contact with the conveyance roller 29 and is rotated in the feeding direction of the sheet-like document P, even if several sheets of sheet-like document P are fed by the pickup roller 23, for example, they may be fed. The sheet-shaped document P smoothly passes through the gap between the transport roller 29 and the separation roller 36 by the transport roller 29 and the feed roller 37 (see FIG. 4). When any of the sheet-shaped originals P that have passed through the gap between the transport roller 29 and the separation roller 36 is detected by the sheet-shaped original detection sensor 52, the solenoid means 47 is de-energized, and the tension spring 51. As a result, the feed roller 37 is separated from the carrying roller 29, and the separating roller 36 is raised in a direction in which the separating roller 36 comes into contact with the carrying roller 29 with a predetermined pressing force. Then, of the several sheet-shaped originals P sandwiched by the conveying roller 29 and the separating roller 36, the sheet-like original P that comes into contact with the conveying roller 29 is fed by the frictional contact force with the conveying roller 29. The sheet-shaped original P conveyed in the direction and coming into contact with the separation roller 36 is returned in the direction opposite to the feeding direction by the frictional contact force with the separation roller 36 (see FIG. 4). Thus, the frictional contact force of the separation roller 36 with respect to the sheet original P by the conveyance roller 29 is the only one sheet-shaped document P finally left between the conveyance roller 29 and the separation roller 36. Based on the fact that it is larger, it is fed to the next sheet-shaped document reading section (see FIG. 4). When the first sheet-shaped document P is separated from the detection action of the sensor 52, the solenoid means 47 is excited again to separate the separation roller 36 from the conveyance roller 29 and the feed roller 37 is raised, and at the same time, the pickup roller. 23 is lowered (see FIG. 4), the above-described steps 1 to 3 are repeated again, and the sheet-like originals P in the stacked state are sequentially fed one by one to the original reading section.

In the above-described embodiment, the structure in which the solenoid means 47 in the excited state is set to the non-excited state by turning on the sheet-shaped document detection sensor 52 has been described. For example, in FIG. The solenoid means 47 may be exemplified by reversing the position of the spring 51 and turning on the sheet-shaped document detection sensor 52. Alternatively, the link members 46, 46 may be omitted and the lever member 39 and the lever member 41 may be operated by separate solenoid means. Further, although the separation feeding unit 25 uses the rollers of the conveying roller 29, the separation roller 36 and the feeding roller 37, the belt may be used.

(G) Effects of the Invention As described above, according to the present invention, the conveying member that rotates in the sheet feeding direction and the sheet member that rotates in the direction opposite to the sheet feeding direction and contact the conveying member. A sheet material detecting means is disposed downstream of the separating member that is freely displaceable in the sheet material feeding direction, and is a feeding member that is displaceably contactable and separable from the conveying member and rotates in a sheet material feeding direction. When the sheet material is not detected by the detecting means, the conveying member and the separating member are brought into a non-contact state, and at the same time, the conveying member and the feeding member are brought into contact with each other, and the sheet material is detected by the detecting means. When detected, the conveying member and the separating member are brought into contact with each other and at the same time the conveying member and the feeding member are brought into non-contact state, so that the leading end of the sheet material collides with the reversing separating member. Na Since the sheet is always conveyed by the conveying member and the feeding member and securely held by the conveying member and the separating member before being separated and fed, the occurrence of jams and feeding defects is prevented, and particularly, a sheet material having a defect at the leading end is provided. It is also possible to feed thin and thin sheet materials satisfactorily, and there is no mechanism that requires delicate mounting work, adjustment work, etc., and mechanical manufacturing is extremely easy. Moreover, since there is no possibility of aging, it is possible to obtain a sheet material separating and feeding apparatus which is inexpensive, easy to handle, and stable in performance.

[Brief description of drawings]

1 to 4 are views relating to a sheet material separating and feeding apparatus according to the present invention. FIG. 1 is a side sectional view of an essential part thereof, FIG. 2 is a perspective view of the essential part thereof, and FIG. FIG. 4 is an application diagram of the apparatus, and FIG.
FIGS. 5 to 15 show the main structure of the sheet material separating and feeding apparatus according to the conventional example, and FIGS. 16 and 17 show general operation explanatory views. 21 …… Sheet material separating / feeding device (automatic sheet feeding device), 29 …… Conveying member (conveying roller), 36 …… Separating member (separating roller), 37 …… Feeding member (feeding roller), 52 …
... Sheet material detection means (sheet-shaped document detection sensor), P ...
… Sheet material (sheet original).

Claims (1)

[Claims] 1. A sheet material separating member, comprising: a conveying member that rotates in a sheet material feeding direction; and a separating member that rotates in a direction opposite to a sheet material feeding direction and that is displaceably contactable with the conveying member. In the feeding device, the sheet material detecting means is disposed on the downstream side of the sheet material feeding direction between the conveying member and the separating member, and the sheet material detecting means is disposed so as to be movable toward and away from the conveying member and to feed the sheet material. If a sheet is not detected by the above detection means by disposing a rotating feed member,
When the conveying member and the separating member are brought into a non-contact state, the conveying member and the sending member are brought into a contact state at the same time, and when the sheet material is detected by the detecting means, the conveying member and the separating member are brought into a contact state. At the same time, the sheet material separating and feeding apparatus is characterized in that the conveying member and the feeding member are brought into a non-contact state.