JPH0141717Y2 - - Google Patents

Description

[Detailed Description of the Invention] Technical Field The present invention relates to a sheet-like conveyance reversing device that reverses the conveyance direction of an advancing sheet-like conveyance object and sends it out.

BACKGROUND OF THE INVENTION It has been well known that a reversing device of the type described above is used in a copying machine or the like for the purpose of reversing a conveyed sheet of copy paper or a document. For example, in a double-sided copying machine, in order to copy a sheet of paper that has been copied on one side and then copy the other side of the sheet, it is necessary to reverse the sheet. Also, regardless of double-sided or single-sided copying,
It is also well known to invert the copy paper after the copying process is completed and then discharge it out of the machine. As one of the reversing devices used for this purpose, the devices shown in FIGS. 1 to 3 have been proposed. This device consists of a pair of conveyor rollers 1a and 2 as shown in FIG.
A sheet-like conveyed object (for example, a copy paper) 4a is advanced in the direction of arrow A by the first conveying means 3a consisting of a conveying means 3a, followed by a conveying direction changing means 7a having two rollers 5a and 6a, and a pair of feeding rollers. 8
By the second conveyance means 10a consisting of a, 9a,
The sheet-like conveyance object 4a is further advanced. Then, as shown by the chain line, the rear end 11a of the sheet-like conveyed object 4a
are the conveyance rollers 1a and 2 in the first conveyance means 3a.
When the rollers have finished passing through a, the rotation directions of the rollers 5a, 6a; 8a, 9a are reversed as shown in FIG.
The sheet-like conveyance object 4a is moved backward in the direction of arrow B, and the sheet-like conveyance object 4a is moved by the third conveyance means 13a consisting of the above-mentioned conveyance roller 2a and another conveyance roller 12a.
a is sent out from the reversing device. Further, by the conveyance direction converting means 7a, arrow B
The leading end 11a of the sheet-like conveyed object 4a sent in the direction
(the rear end before the conveyance direction is changed) is gripped by the conveyance rollers 2a, 12a as shown in FIG. Conveying direction converting means 7a
One roller 5a is separated from the other roller 6a. In this way, both rollers 5
If a and 6a are separated from each other, the rear end 14a (the leading edge before the direction change) of the sheet-like conveyed object 4a described above passes between the rollers 5a and 6a of the conveyance direction changing means 7a, as shown in FIG. Even if a subsequent sheet-like conveyed object 104a enters between the rollers 5a and 6a before the sheet-like conveyed object 104a is finished, the subsequent sheet-like conveyed object 104a
is not hindered in its progress by these rollers 5a, 6a. In other words, before the rear end 14a of the preceding sheet-like conveyed object 4a leaves between the rollers 5a, 6a, the following sheet-like conveyed object 104a can be sent between these rollers 5a, 6a, and the sheet-like conveyed object 4a can be fed between these rollers 5a, 6a. The distance between the objects 4a and 104a can be narrowed, and therefore, this reversing device can be particularly advantageously employed in high-speed copying machines with high copying speeds. Also, the preceding sheet-like conveyed object 4
Since both rollers 5a and 6a of the conveyance direction converting means 7a are separated from each other after the tip end 11a of the sheet starts receiving conveyance force by the third conveyance means 13a, the feeding action of the sheet-like conveyed object 4a is inhibited. Nor.

The reversing device shown in FIGS. 1-3 has the advantages mentioned above. However, on the other hand,
When switching the conveying direction of the sheet-like conveyed object to the opposite direction (FIG. 2), the rollers 5a and 6a of the conveying direction changing means 7a arranged between the first and second conveying means
and feed rollers 8a, 9a of the second conveyance means 10a.
Since the direction of rotation of the rollers must be reversed, it is necessary to use an expensive reversible motor as a drive device for driving these rollers, which inevitably increases the cost of the reversing device. Also, the roller 6a of the conveyance direction converting means 7a
When the distance L (FIG. 3) between the second conveyance means 10a and the feed roller 9a is short, the rear end 14a of the sheet-like conveyed object 4a that is switched in direction and moves in the direction of arrow B is Before the copy sheet 104a passes through the rollers 10a of the means, the leading edge 114a of the succeeding copy sheet 104a moving forward in the direction of arrow A reaches the second conveying means 10a.
If it reaches this point, the tip 114a may hit the feed roller 8a, and its progress may be hindered. For this reason, it is necessary to increase the distance L between both rollers 6a and 9a, but if this is done, the disadvantage is that the structure of the reversing device becomes larger. In order to eliminate this inconvenience, the leading end 11 of the preceding sheet-like conveyed object 4a
When a is gripped by the conveyance rollers 2a, 12a, the feed roller 8a is separated from the other feed roller 9a so that the progress of the subsequent sheet-like conveyed object 104a is not obstructed by the feed rollers 8a, 9a. It is also possible to do so. However, if this is done, the configuration of the reversing device will not only become more complicated, but also the subsequent conveyance of the sheet-shaped object will become unstable, increasing the possibility of causing conveyance troubles.

Purpose This invention was made based on the above recognition,
The object thereof is to provide a sheet-like conveyed object reversing device that can reverse the conveying direction of a sheet-like conveyed object without using an expensive reversible motor and can also achieve miniaturization of the structure.

Configuration In order to achieve the above object, the present invention includes a first conveying means for advancing a sheet-like conveyed object, and a first conveying means disposed downstream of the first conveying means when viewed in the advancing direction of the sheet-like conveyed object, A second conveying means that applies a conveying force to the sheet-like conveyed object in a direction to further advance the sheet-like conveyed object, and is disposed between the first conveying means and the second conveying means, and is arranged between the first conveying means and the second conveying means to apply a conveying force to the sheet-like conveyed object in a direction that moves the sheet-like conveyed object further forward. a conveying direction converting means for converting the direction to the opposite direction and conveying the same; and a conveying force is applied to the conveyed object in a direction in which the sheet-like conveyed object conveyed in the opposite direction is sent out by the conveying direction converting means. In the sheet-like conveyed object reversing device, the conveyance direction converting means includes at least one return roller that is rotationally driven only in a direction in which the sheet-like conveyed object is conveyed in the opposite direction; At least one pressing member is supported so as to be able to move toward and away from the roller, and the pressing member is separated from the return roller before the rear end of the advancing sheet-like conveyed object leaves the first conveying means, and the pressing member is moved away from the return roller. After the rear end leaves the first conveyance means, the third
The pressing member is brought into contact with the return roller so as to exert a conveying force directed toward the conveying means, and after the sheet-like conveyed object begins to receive the conveying force by the third conveying means, the sheet-like conveyed object is an actuating means for separating the pressing member from the return roller at an appropriate time before the succeeding sheet-like conveyed object reaches the conveyance direction changing means, and the second conveying means moves the sheet-like conveyed object in a direction in which it advances. at least one feed roller that is rotationally driven only, and when the pressing member contacts the return roller and conveys the sheet-like conveyed object in the opposite direction, the pressing member and the return roller exert an effect on the sheet-like conveyed object. The conveying force is larger than the force exerted on the sheet-like conveyed object by the feed roller, and the conveying force exerted on the sheet-like conveyed object by the third conveying means is larger than the force exerted on the sheet-like conveyed object by the feed roller. Before the rear end of the sheet-like conveyed object, which is larger than the force exerted on the object and is conveyed in the opposite direction, leaves the feed roller, a subsequent sheet-like conveyed object is fed between the sheet-like conveyed object and the feed roller. The second conveying means converts the conveying direction so that the forward conveying force exerted by the feed roller on the subsequent sheet-like conveyed object becomes larger than the frictional force acting between both sheet-like conveyed objects. The present invention proposes the reversing device, characterized in that the conveying force exerted on the sheet-like conveyed object by the third conveying means and the third conveying means is set respectively.

Embodiment The reversing device according to the present invention can be employed in various types of equipment, and as an example, a specific example in which the present invention is applied to a copy paper reversing device in a double-sided copying machine will be described below.

FIG. 4 is an explanatory diagram schematically showing a part of a double-sided copying machine, and first the outline of the overall configuration of this copying machine will be explained. The copy paper (sheet-like conveyed object) 4 stored in the paper feed cassette 20 is transported by a paper feed roller 21,
The sheets are sent one by one from the cassette 20 to the registration roller pair 24 by the separating roller 22 and the feeding roller 23 paired therewith (arrow A ₁ ).

On the other hand, in this example, the photoreceptor 2 is formed into a drum shape.
5 is rotated clockwise in the figure, and at this time, a toner image corresponding to the image of the original (not shown) is formed on the surface of the photoreceptor by image forming means such as an exposure device and a developing device (not shown). .

The above-mentioned copy paper 4 sent to the registration roller pair 24 is fed onto the surface of the photoreceptor 25 in synchronization with the rotation of the photoreceptor 25, and the toner image on the photoreceptor is transferred to the copy paper by the transfer charger 26. The copy paper is then separated from the photoreceptor 25 by a separation charger 27 (arrow A ₂ ). The copy paper separated from the photoreceptor 25 is then conveyed by the conveyor belt 28, as shown by arrow _A3 , and passes through a pair of rollers 30 of the fixing device 29, at which time the toner image on the copy paper is transferred to the copy paper. is fixed on the surface of The copy paper on which the copy image (toner image) has been formed on one side is further transferred to the feed roller pair 31 by the sheet-like conveyed material reversing device 100 according to the present invention.
(arrow A ₄ ).

The copy paper 4 transported to the reversing device 100 is transported to different destinations depending on whether the final copy mode is one-sided copying or double-sided copying. That is, in the case of single-sided copying, the copy paper is conveyed in the direction shown by arrow C, and is discharged onto the paper discharge tray 33 outside the machine by the pair of discharge rollers 32, and in the case of double-sided copying,
Turn the edge of the copy paper, which was previously warm at the rear edge, into the leading edge.
It is sent out from the reversing device 100 in the direction indicated by arrow _B1 . These operations and the configuration of the reversing device 100 will be explained in detail later.

The copy paper leaving the reversing device 100 is sent to the intermediate tray 34 as shown by arrow _B2 and placed on the tray 34. At this time, the side of the copy paper on which the copy image is formed is facing upward.

The above operation is repeated a predetermined number of times, and the intermediate tray 34
When a predetermined number of copies are deposited on the tray 34, the paper feed roller 35 is rotated counterclockwise, and the copies placed on the tray 34 are transferred to a separation roller 36, a feed roller 37, and an intermediate roller pair 38. Therefore, it is sent again to the registration roller pair 24 described above (arrow B ₃ ),
Next, in the same manner as described above, the photoreceptor 2
The toner image is transferred to the surface of 5. At this time, since the leading and trailing ends of the copy paper have already been reversed by the reversing device 100, the front and back sides of the copy paper are reversed from when they first reached the photoreceptor 25, and the toner image is transferred first. Place the opposite side of the photoreceptor 2
I'm heading towards 5. Therefore, the toner image is transferred to the surface opposite to the surface on which the copy image was previously formed.
The copy paper on which a copy image has been formed on each side in this way is transferred to a fixing device 29 and a reversing device 100.
After passing through, the paper is conveyed in the direction of arrow C and delivered to the output tray 3.
3 is discharged on top.

Next, the configuration of the sheet-like conveyed object reversing device 100,
We will clarify its effect.

As mentioned above, the copy paper 4 that has been copied on one side and is sent to the reversing device 100 in the direction of the arrow _A4 passes through the guide plate 3 as shown by the dashed line in FIG.
It is moved forward by the first conveying means 3 while being guided by 9 and 40 . The first conveyance means 3 in this example includes a conveyance roller 1 that rotates clockwise, and a pair of conveyance rollers 2 that rotate counterclockwise. These are respectively provided on support shafts 41 and 42 and are fixedly spaced apart from each other in the axial direction.
The copy paper 4 is conveyed while being held between both rotating conveyance rollers 1 and 2.

A conveying direction converting means 7 is provided on the downstream side of the first conveying means 3 when viewed in the conveying direction of the copy paper, and a second conveying means 10 is provided further downstream of the first conveying means 3. A switching claw 43 supported by a shaft 44 is disposed between the transport direction converting means 7 and the transport direction changing means 7. The switching claw 43 can be rotated between the position shown by the solid line and the position shown by the broken line by rotating its shaft 44.

When the copy paper carried into the reversing device 100 is to be ejected from the machine with a single-sided copy, the switching pawl 43 is rotated to the position shown by the broken line, and both conveying rollers 1 of the first conveying means 3 are rotated. , 2 is guided by the switching claw 43 and is shown by the solid line in FIG.
The discharge roller pair 3
2 (FIG. 4) onto the paper discharge tray 33 (also shown in FIG. 4). The tip of the switching claw 43 that has reached the position indicated by the broken line enters the slit formed in the guide plate 39, so that the switching claw 43 moves into the guide plate 39.
will not interfere with

When the other side of the copy paper 4 is to be copied, the switching claw 43 is rotated to the position shown by the solid line in FIG. Therefore, the copy paper 4 leaving the first conveying means 3 is guided by the switching pawl 43 and the guide plates 39, 45, while being guided by the conveying direction changing means 7 and the second conveying means 10.
transported to.

As shown in FIGS. 5 and 6, the illustrated conveyance direction converting means 7 includes a plurality of return rollers 6 fixed to a rotating shaft 46 at intervals, and a plurality of return rollers 6 paired with the return rollers 6. The separating roller 5 also has a support shaft 47.
are fixedly supported at intervals in the axial direction. The rotating shaft 46 is rotatably supported by two side plates 48 and 49, and the rotating shaft 46 is supported by a gear 5 fixed to the end of the shaft 46 together with a return roller 6.
It is rotatably driven only in the clockwise direction in FIG. 5 by a drive device (not shown) via a transmission device including numeral 9. That is, the return roller 6 is rotationally driven only in the direction in which the copy paper is conveyed in the opposite direction, which will be described later. The support shaft 47 is rotatably supported at both ends by arms 50, 50a as shown in FIG.
is fixed to the pivot 51. The pivot shaft 51 is rotatably supported by both side plates 48 and 49 via bearings, and an actuating plate 52 is fixed to one end thereof.
and a support member 57 fixed to the side plate 48, each end of a first tension spring 53 is moored, and by this tension spring 53, the actuating plate 52, the pivot 51, and the arms 50, 50a are The rotation habit is given in the counterclockwise direction in the figure. Further, a plunger 56 of a solenoid device 55 is connected to the actuation plate 52 via a second tension spring 54 located on the opposite side of the first tension spring 53, and the solenoid device 55 is connected to the support plate as shown in FIG. It is fixedly supported by the side plate 48 via 58.

Normally, the solenoid device 55 is deenergized, and therefore the actuating plate 52, the pivot shaft 51, the arms 50, 50a, and the contact/separation roller 5 are held in the position shown by the solid line in FIG. The separation roller 5 is spaced apart from the return roller 6.

When the solenoid device 55 is energized, its plunger 56 is pulled to the right in FIG.
0 and 50a and the support shaft 47 to the position shown by the two-dot chain line in FIG. 5, and come into pressure contact with the return roller 6. Further, as will be described later, the copy paper 4 is
When passing between the copy paper 4 and the return roller 6, the copy paper 4 passes through a paper passing range shown as E in FIG. First transmission roller 105 and second transmission roller 10
6 are fixed, and when the separation roller 5 contacts the return roller 6 directly or through the copy paper, both the transmission rollers 105 and 106 directly press against each other,
The rotation of the rotation shaft 46 is transmitted to the support shaft 47 by the frictional force. in this case,
It is desirable that both transmission rollers 105 and 106 be made of a high friction material, such as rubber, to increase the coefficient of friction around them so that force can be transmitted reliably.

On the other hand, the second conveying means 10 in this example is the fifth
As shown in the drawings and FIG. 8, it has a plurality of feed rollers 8 fixed to a rotating shaft 60 and a guide plate 61 with which the rollers 8 can come into contact. The illustrated guide plate 61 is composed of a plate. An electromagnetic clutch 63 is provided at the end of the rotating shaft 60, and the gear 6
2 is rotatably supported. Electromagnetic clutch 6
3 has a core 64 and a coil 65 wound around it, and the core 64 is fixed to the rotating shaft 60 so as to be able to rotate together with the rotating shaft 60, but the coil 65 is not rotatable. The core 64 does not rotate together with the coil 65.

As described above, the copy paper 4 shown by the dashed line in FIG.
When the paper is fed into the conveying direction changing means 7 while being guided by the solenoid device 55, the solenoid device 55 is deenergized, so that the approaching/separating roller 5 is separated from the return roller 6 as shown by the solid line in FIG. That is,
Before the trailing edge 11 of the advancing copy paper 4 leaves the first conveyance means 3, the contact/separation roller 5 is separated from the return roller 6. Therefore, the return roller 6 is the fifth
Although the copy paper 4 is constantly rotating in the clockwise direction in the figure, that is, in the direction in which the copy paper 4 is conveyed in the opposite direction, the copy paper 4
The tip 14 passes through the conveyance direction converting means 7 without substantially receiving conveying force from the return roller 6, and is connected to the feed roller 8 in the second conveying means 10.
It is sent between the guide plate 61 and the guide plate 61 . At this time,
The coil 65 of the electromagnetic clutch 63 shown in FIG. , gear 62
The rotation is transmitted to the rotating shaft 60, and the feed roller 8 rotates clockwise in FIG. Therefore, the copy paper 4 held between the feed roller 8 and the guide member 61 receives a conveyance force from the feed roller 8, and continues to move forward as shown by the dashed line in FIG.

In order for the feed roller 8 to reliably exert a conveying force on the copy paper 4, the frictional force between the peripheral surface of the feed roller 8 and the copy paper 4 is greater than the frictional force between the copy paper 4 and the guide plate 61. The coefficient of friction between the circumferential surface of the roller 8 and the surface of the guide plate 61 is set in advance so that For example, it is advantageous to configure the feed roller 8 with a soft roller having a high coefficient of friction and excellent wear resistance, such as a soft urethane foam. Further, the copy paper 4 between the feed roller 8 and the guide plate 61 is pressed against the surface of the guide plate 61 by the feed roller 8, but at this time, a plurality of beads 66 ( (Fig. 8) is formed on the guide plate 61, and the feed roller 8 is positioned between the beads to give so-called stiffness to the copy paper 4 being conveyed and to apply a uniform conveyance force to the copy paper. It is desirable to give.

On the other hand, a first actuator 68 for detecting paper, which is operated by copy paper, is supported by a rotation shaft 69 at or near the position where the first conveyance means 3 is provided. As mentioned above, the rear end 11 (the fifth
When the copy paper 4 passes through the first actuator 68, this is detected by the actuator 68, and after a certain period of time has elapsed from the time of this detection, the trailing edge 11 of the copy paper 4 moves as shown by the two-dot chain line in FIG. , when it leaves both conveying rollers 1 and 2 and reaches the position indicated by the symbol D, for example, the solenoid device 55 mentioned above is energized and the electromagnetic clutch 63 is de-energized.

As the solenoid device 55 is energized, the approaching/separating roller 5
is in pressure contact with the return roller 6 through the copy paper 4 as shown by the two-dot chain line in FIG.
is also rotationally driven. Therefore, the return roller 6 and the approaching/separating roller 5 exert a force on the copy paper 4 to transport it in the opposite direction to the direction in which the copy paper has been advanced. Furthermore, since the electromagnetic clutch 63 is disengaged, the connection between the gear 62 and the rotating shaft 60 is released, and the rotating shaft 60 is in a state where it can freely rotate without being transmitted with the driving force from the gear 62. No conveying force is exerted on 4. For this reason, copy paper 4
begins to be conveyed in the opposite direction shown by arrow _B1 in FIG.
It is sent toward the third conveyance means 13 while being guided by.

As described above, after the rear end 11 of the advancing copy paper 4 leaves the first conveyance means 3, the approaching/separating roller is applied so that a conveying force directed toward the third conveyance means 13 is applied to the copy paper 4 5 comes into contact with the return roller 6. Furthermore, when the approaching/separating roller 5 contacts the return roller 6 and conveys the copy paper 4 in the opposite direction, the feed roller 8 does not exert any conveying force on the copy paper 4, so the copy paper 4 is hardly moved away from the feed roller 8. Since no external force is applied or only a slight force is applied, the copy paper can be conveyed in the opposite direction without any trouble. That is, the conveyance direction converting means 7 applies the conveyance direction to the copy paper so that the conveyance force exerted on the copy paper by the approaching/separating roller 5 and the return roller 6 is larger than the force exerted on the copy paper 4 by the feed roller. The magnitude of the conveying force exerted on the object is set.

Note that it is desirable to set the friction coefficient of the surface of the separation roller 5 against the copy paper 4 to be relatively large so that the roller 5 can exert a large force on the copy paper 4. When the leading edge 14 of the copy paper 4 that is being fed in _four directions hits the return roller 6, it slides on the surface of the roller 6, i.e., it can continue moving forward without being obstructed by the roller 6. It is advantageous to set the coefficient of friction of the surface of the return roller 6 to be relatively small.
To achieve this purpose, it is desirable that the separation roller 5 be made of, for example, low hardness rubber, and that the return roller 6 be made of, for example, polyacetal resin, or that the surface of the return roller 6 be made of a smooth resin or metal surface.

The third conveying means 13 in this example is composed of the previously described conveying roller 2 and a plurality of conveying rollers 71 that are paired with this and fixed to a shaft 70, and the copy paper 4 is conveyed to these conveying rollers 2, 71. It is conveyed while being held and sent out of the reversing device 100 (see FIG. 9). Then, while being guided by the guide plates 72 and 73, the paper is sent to the intermediate tray 34 as described above with reference to FIG. In this way, the copy sheet 4 is switched back by the reversing device 100, and the other side of the sheet can be subjected to the copying process as described above.

By the way, subsequent copy sheets are fed sequentially after the above-mentioned copy paper 4, but in order to increase the copying speed of the copying machine, the gap between the preceding copy paper and the following copy paper should be made as narrow as possible. There is a need. Therefore, in the illustrated reversing device 100, the trailing edge 14 of the preceding copy sheet 4, which is indicated by the two-dot chain line in FIG. This feed roller 8
Even if the distance between the two copy sheets is narrow enough to reach , the structure is such that they do not interfere with each other. The configuration related to this will be clarified below.

As mentioned above, the conveyance direction of the copy paper 4 is the forward direction.
It is converted from A ₄ to the opposite direction B ₁ and sent to the third conveyance means 13, but its tip 11 (the rear end before the conveyance direction change) is held by both conveyance rollers 2, 71, and When the second actuator 7, which is disposed at or near the third conveyance means 13 and is supported by the rotation shaft 75,
4 is actuated by the leading edge 11 of the copy paper 4, which again de-energizes the solenoid device 55 and starts energizing the electromagnetic clutch 63. Therefore, the contact/separation roller 5 separates from the return roller 6, and at the same time, the feed roller 8 is rotated clockwise again. Along with this, the feed roller 8 begins to exert a conveyance force on the copy paper 4 in the forward direction A ₄ , but the conveyance force ( _F1 this
) is set to be larger than the force (F ₂ ) that the feed roller 8 exerts on the copy paper 4 (F ₁ > F ₂ ), and therefore the copy paper 4 is pushed away from the feed roller 8. The copy paper ₄ is transported in the direction of arrow B1 without any trouble even if subjected to force, and the feed roller 8 rotates clockwise while slipping on the copy paper 4.

As described above, when the contact/separation roller 5 separates from the return roller 6, the following copy paper 104, shown by the dashed line in _FIG . Even if the copy paper 104 is advanced and its leading end 114 enters between the separation roller 5 and the return roller 6, the copy paper 104 can continue to advance without being hindered by these rollers 5 and 6. . Furthermore, since the electromagnetic clutch 63 is energized and the feed roller 8 is rotating clockwise in FIG. Also, the copy paper 104 is further subjected to a forward conveyance force by the feed roller 8. That is, when a subsequent copy paper 104 is fed between the copy paper 4 and the feed roller 8 before the trailing edge 14 of the copy paper 4 conveyed in the opposite direction leaves the feed roller 8, the feed roller 8 The conveyance force exerted on the copy paper 104 by the second conveyance means 10 is set so that the conveyance force in the forward direction exerted on the copy paper 104 is greater than the frictional force acting between the two copy sheets 4, 104. It has been done. Therefore, the succeeding copy paper 104 is reliably advanced by the feed roller 8, and since the copy papers slip each other, the conveyance of the preceding copy paper 4 in the direction of arrow _B1 is not hindered.

As described above, it is possible to narrow the interval between copy sheets that are fed one after the other, and the method of determining this interval is more specifically as follows.

First, as shown in FIG. 10, the distance between the contact point t 1 of the two transport rollers 1 and ₂ and the contact point t ₂ of the approaching/separating roller 5 and return roller 6 is a, and both transport rollers 2,
Let b be the distance between the contact point _t3 of 71 and the above contact point _t2 . Further, a line segment connecting both contact points t ₂ and t ₃ is designated as G, which passes through a location D where the trailing edge 11 of the copy paper is located at the time when the copy paper is changed from the forward direction to the reverse direction.
Consider an arc F centered on the tangent point _t2 , and let H be the intersection of the line segment G and the arc F.

When the rear end 11 of the copy paper 4 reaches position D as shown by the solid line in FIG. 10, the copy paper 4 falls onto the switching claw 43 (see FIG. 5) as shown by the broken line. is sent in the direction of arrow B ₁ , and its tip 1
1 is gripped by the conveying rollers 2 and 71, and at this time, the approaching/separating roller 5 separates from the return roller 6 as shown in FIG. 11, as described above. If the leading edge 114 of the succeeding copy sheet 104, indicated by a dashed line in FIG. 11, reaches the return roller 6 after the contact/separation roller 5 leaves the return roller 6, its progress will not be hindered. In other words, if both copy sheets 4, 104 are fed while maintaining such a positional relationship, it is possible to prevent interference between the two copy sheets or transport trouble. Therefore,
The radius of the arc centered at t ₂ is r, and the distance from the trailing edge of the preceding copy sheet to the leading edge of the following copy sheet is l.
(In this case, l is the distance when both copies are moving in the same direction.) As is well known, when approximately the following equation holds,
It is possible to transport both copy sheets within the reversing device while preventing transport troubles.

(a-r)+(br-r)=a+b-2r≦l+a (1) Rearranging equation (1), b-2r≦l (2) (However, assuming that the circumferential speed of each roller is the same, (Assume that there is no slip between each roller and the copy paper.) If the above equation (2) cannot be satisfied, the approach/separation roller 5
The subsequent copy paper 104 is removed before it leaves the return roller 6.
The leading edge 114 of the copy paper reaches the nip between the approaching/separating roller 5 and the return roller 5, and the progress of the copy paper is obstructed. In addition, in order to prevent this inconvenience, the contact/separation roller 5
If the leading edge of the copy paper 4 is moved away, the contact/separation roller 5 will be separated before the leading edge of the copy paper 4 is gripped by the conveyance rollers 2, 71, so that the copy paper 4 will move in the direction of the arrow.
B Unable to receive conveyance force in _one direction, causing conveyance troubles.

Although one embodiment of the present invention has been described above, the structure of the present invention can be modified in various ways. For example, the timing at which the approaching/separating roller 5 approaches and separates from the return roller 6 and the timing at which the feed roller 8 starts driving or releases the drive may be appropriately shifted. For example, in the above embodiment, when the rear end 11 of the advancing copy paper 4 reaches the position D, the contact/separation roller 5 is brought into pressure contact with the return roller 6, and at the same time, the drive of the feed roller 8 is released. After releasing the drive of the roller 8, when the contact/separation roller 5 is brought into pressure contact with the return roller 6, the copy paper 4 is temporarily stopped and then fed in the direction of the arrow _B1 , which prevents excessive external force from being applied to the copy paper. It is possible to prevent the inconvenience caused by the copying paper, and to prevent copy paper skew. Further, the timing of separating the contact/separation rollers 5 can be changed as appropriate; in other words, the succeeding copy paper 104 reaches the conveyance direction changing means 7 after the copy paper 4 begins to receive the conveyance force from the third conveyance means 13. It is only necessary to separate the contact/separate rollers at an appropriate time beforehand.

Furthermore, since the contact/separation roller 5 presses the copy paper against the return roller 6 and exerts a conveyance force on the copy paper, other appropriate pressing members may be used in place of the contact/separation roller.
For example, a sphere supported by a return roller so as to be able to approach and separate from it,
A blade, plate, etc. may also be used.

In the illustrated embodiment, a solenoid device, a tension spring, an arm, an actuator, etc. are used as the actuating means for bringing the pressing member consisting of the approaching/separating roller toward and away from the return roller at the above-mentioned predetermined timing, but other suitable means are used. It is clear that other means may be used. For example, in the embodiment, two actuators 68 and 74 are used, but only one actuator 68 is used, and the pressing member such as the approaching/separating roller is returned depending on the time after it detects the trailing edge of the copy paper. It can also be separated from the rollers.

Further, as shown in FIG.
The bearing 80 is vertically movably supported in a long hole 81 formed in the long hole 81 in the vertical direction, and biased downward by a compression spring 83 that is locked to an upper locking part 82 of the long hole 81. It can also be configured to do so. In this case, it is a matter of course that the arm 50a on the other side is configured in the same manner. In this way, when the contact/separation roller comes into contact with the return roller 6, both ends of the support shaft 47 are elastically pressed against the return roller 6 by the compression spring 83, and the entire longitudinal direction of the support shaft 47 is Each contact/separation roller 5 can be brought into pressure contact with the return roller 6 with uniform force over the period. This configuration can be particularly advantageously adopted when the surface of the return roller 6 has a high hardness.

Further, in the illustrated example, the guide plate 61 is used as a guide member that is a counterpart member of the feed roller 8 in the second conveyance means 10, but instead of this, other members, such as a plurality of claw-shaped guides as shown in FIG. 13, are used. 161 and connected by a shaft 90, it is also possible to provide a conveyance force to the copy paper passing between the feed roller 8 and these claw-shaped guides 161.

Also, both conveyance rollers 2 and 71 of the third conveyance means 13
The conveying force F ₁ exerted on the copy paper by the second conveying means 1
0 should be larger than the force F ₂ exerted on the copy paper. ₃ , it is also advantageous to configure the structure so that the relationship F ₃ >F ₂ is satisfied. If you do this, you can feed the copy paper using arrow B ₁
Even when the drive of the feed roller 8 is cut off slightly after the contact/separation roller 5 comes into contact with the return roller 6 to change the direction, the copy paper can be reliably conveyed in the direction of the arrow _B1 . can. Furthermore, if the conveying force exerted on the copy paper by the approaching/separating roller 5 and the return roller 6 is larger than the force F ₂ exerted on the copy paper by the rotationally driven feed roller 8, means for turning on and off the drive of this roller 8 ( Even if the electromagnetic clutch (in the illustrated example) is omitted and the feed roller 8 is kept constantly rotating, it is possible to convey the copy paper in the direction of arrow _B1 by the approaching/separating roller and the return roller.

The sheet-like conveyed object reversing device according to the present invention can be used in various ways other than a copy paper reversing device in a double-sided copying machine. For example, it can be used as a device for reversing copy sheets to align the order of the copy sheets when they are ejected, or as a device for aligning the order of copy sheets, or as a device for aligning the order of copy sheets when they are discharged. It can be widely applied to inverting devices, etc.

In this specification, when the pressing member (approach/separate roller of the embodiment) is brought into contact with and separated from, or brought into contact with, the return roller, "contact", "contact", and "contact" are used. ", etc. means that the pressing member is brought into direct contact with or in close proximity to the return roller, or brought into contact through a sheet-like conveyed object.
It is clear from the above explanation.

Effects According to the present invention, it is possible not only to narrow the gap between the preceding sheet-like conveyed object and the following sheet-like conveyed object while preventing interference between them, but also to allow the sheet-like conveyed objects to be conveyed in the opposite direction. Since the conveyance direction changing means has a return roller that rotates in the same direction and a pressing member that can move toward and away from the roller, there is no need to use an expensive reversible motor as a device to drive the means, and the reversing device It has become possible to reduce costs. Further, the second conveying means can apply a conveying force to the sheet-like conveyed object in the direction of advancing it, and the following copy paper is applied to this means before the preceding sheet-like conveyed object leaves the second conveying means. Even when the conveyance direction is reached, the means can advance this subsequent copy sheet, so it is possible to narrow the distance between the conveyance direction converting means and the second conveyance means, thereby making the structure more compact.

[Brief explanation of the drawing]

1 to 3 are explanatory diagrams showing an example of a conventional sheet-like conveyed object reversing device, FIG. 4 is an explanatory diagram showing an outline of a double-sided copying paper equipped with the reversing device according to the present invention, and The figure is a cross-sectional view of the reversing device, with the side plate omitted; FIG. 6 is a cross-sectional view taken along the line - - of FIG. 5, with some elements omitted;
FIG. 7 is a view taken in the - line direction of FIG. 5, with some elements omitted like in FIG. 6, FIG. 8 is a sectional view taken along the - line of FIG. 5, and FIG. A sectional view similar to FIG. 5 showing the state when the succeeding copy paper is carried in, and FIGS. 10 and 11 are explanatory diagrams clarifying how to determine the distance between the preceding copy paper and the following copy paper. , FIG. 12 is a partial sectional view showing a preferable support mode of the support shaft for the contact/separation roller, and FIG.
FIG. 7 is a perspective view showing another embodiment of the guide member in the conveyance means. 3...first conveyance means, 6...return roller, 7...
...Conveyance direction conversion means, 10...Second conveyance means, 1
3...Third conveyance means, 100...Reversing device, 8...
...Feed rollers, 11, 14...rear end.

Claims (1)

[Claims for Utility Model Registration] A first conveying means for advancing a sheet-like conveyed object;
a second conveying means disposed downstream of the first conveying means when viewed in the forward direction of the sheet-like conveyed object, and exerting a conveying force on the sheet-like conveyed object in a direction to further advance the sheet-like conveyed object; a conveying direction converting means disposed between the first conveying means and the second conveying means, for converting the conveying direction of the sheet-like conveyed object to a direction opposite to the forward direction and conveying the same; Therefore, in the sheet-like conveyed object reversing device comprising a third conveying means that exerts a conveying force on the sheet-like conveyed object in the direction to send out the sheet-like conveyed object conveyed in the opposite direction, the conveying direction converting means at least one return roller that is rotationally driven only in the direction in which the conveyed object is conveyed in the opposite direction; at least one pressing member that is supported so as to be able to approach and separate from the return roller; The rear end is the first
Before leaving the conveying means, the pressing member is separated from the return roller, and after the rear end of the sheet-like conveyed object leaves the first conveying means, a conveying force is applied to the sheet-like conveyed object toward the third conveying means. After the pressing member is brought into contact with the return roller and the sheet-like conveyed object begins to receive the conveying force by the third conveying means, the subsequent sheet-like conveyed object following this sheet-like conveyed object is conveyed. an actuating means for separating the pressing member from the return roller at an appropriate time before reaching the direction changing means, and the second conveying means is rotatably driven only in the direction in which the sheet-like conveyed object is advanced. A feeding roller is provided, and when the pressing member contacts the return roller and conveys the sheet-like conveyed object in the opposite direction, the conveying force exerted on the sheet-like conveyed object by the pressing member and the return roller is applied to the feeding roller. Therefore, the force exerted on the sheet-like conveyed object is greater than the force exerted on the sheet-like conveyed object, and the conveying force exerted on the sheet-like conveyed object by the third conveying means is larger than the force exerted on the sheet-like conveyed object by the feed roller. , and when a subsequent sheet-like conveyed object is fed between the sheet-like conveyed object and the feed roller before the rear end of the sheet-like conveyed object conveyed in the opposite direction leaves the feed roller, the following sheet-like conveyed object is The second conveying means, the conveying direction converting means, and the third conveying means are configured such that the conveying force in the forward direction exerted on the sheet-like conveyed object is larger than the frictional force acting between both sheet-like conveyed objects. The above-mentioned reversing device is characterized in that the conveying force exerted on the sheet-like conveyed object is set respectively.