JPH04292341A - Sheet conveying device - Google Patents

Abstract

PURPOSE:To perform drive of a feed roller and rollers for a plurality of conveying means positioned downstream thereof by a single main gear connected to a drive source. CONSTITUTION:A plurality of conveying means 13 and 20 and a main gear 31 connected to a drive source M are located downstream of a feed roller 3. A driven gear 11 coupled to the feed roller through an electromagnetic clutch 12 and driven gears 16 and 22 of conveying means 13 and 20 are disposed in a position where they are engageable with the main gear 31. A sheet P is fed through rotation of the main gear 31 and conveyable through U-turn conveyance passages 27 and 29 by the conveying means 13 and 20. This constitution causes drive of the feed roller 3 and the conveying means 13 and 20 by the single main gear 31 and reduces the number of gears required for drive.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a paper conveyance device installed in an image forming apparatus such as a copying machine, a printer, a laser beam printer, or a facsimile machine.

0002

2. Description of the Related Art An example of the configuration of a conventional laser beam printer as an image forming apparatus is shown in FIG. In the same figure, reference numeral 101 denotes a paper storage cassette, which is housed in a cassette body 102 and has a loading platform 1 on which paper P is loaded.
03, and a pressure spring 106 for urging the stacked sheets P against the feeding roller 105. Reference numeral 107 is a separating means, which is connected to a friction member 109 and a feeding roller 1.
05 and a pressure spring 110 that applies pressure to the pressure spring 110.

The feed roller 105 is supported by a drive shaft 105a, and a driven gear 1 is attached to the end of the drive shaft 105a.
11 and an electromagnetic clutch 112 are pivotally supported. code 1
Reference numeral 13 denotes a pair of registration rollers, including a conveying roller 115 made of a friction member, a driven roller 116, and this driven roller 1.
16 and an elastic member 117 that urges the transport roller 115. Reference numeral 119 is a detection means for detecting the leading edge of the transported paper P. A paper conveying path 121 consisting of guide plates 121a and 121b is provided between the feeding means 120 including the feeding roller 105 and the pair of registration rollers 113, and a paper conveyance path 121 consisting of guide plates 121a and 121b is provided between the pair of registration rollers 113 and the detection means 119. A paper conveyance path 122 is formed.

A gear 123 is pivotally supported on a drive shaft 115a of the conveyance roller 115, and is connected to a drive source M via a gear train (not shown). The gear 123 is connected to the driven gear 111 via idle gears 125 and 126.

[0005] Now, when the electromagnetic clutch 112 is energized,
Drive of the driven gear 111 is connected to the drive shaft 105a, and the feeding roller 105 starts rotating in the direction of the arrow. As a result, the upper paper P in the paper storage cassette 101 is fed, and after being separated one by one by the separation action of the separation means 107,
It reaches the pair of registration rollers 113 along the conveyance path 121. When the leading edge of the paper P conveyed by the pair of registration rollers 113 is detected by the detection means 119, the movement of the paper P is stopped because the drive from the drive source M is stopped.

After a certain period of time has elapsed, the drive source M is restarted and the paper P is further conveyed. The electromagnetic clutch 112 is restarted, and the paper P is further conveyed. Electromagnetic clutch 11
2, even if the paper is fast, the leading edge of the paper is not connected to the registration roller pair 113.
At the latest, the feed roller 10
5 is in contact with the current.

[0007]

However, in the conventional device described above, the distance from the registration roller pair 113 to the feeding means 120 is long, and the drive from the registration roller pair 113 to the feeding roller 105 is difficult. There was a problem in that the number of gears required to transmit the information increased. Another problem is that the paper storage cassette 101 extends from the main body of the apparatus, requiring a large installation space.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a paper transport device in which the number of gears for driving the feed roller, transport roller, etc. is reduced, and a paper storage cassette can be stored within the main body of the device. It is.

[0009]

[Means for Solving the Problems] The present invention has been made in view of the above-mentioned circumstances. For example, referring to FIG. 1, FIG. 6, FIG. 7, and FIG. ), a feeding means (1) comprising a feeding roller (3) that feeds the sheets one by one, and a drive control mechanism (12) that controls the rotation of the feeding roller (3); Pairs of transport rollers (15, 19, and 2
1, 25);
A main gear (31) that drives the feeding roller (3) and the conveying means (13, 20) and is driven by a drive source (M), wherein the feeding means Drive shaft (3a) of feeding roller (3) in (1)
A driven gear (11) pivotally supported by the conveyor means (13,
20) drive shafts (15a, 21) of the rollers (15, 21)
The driven gears (16, 22) respectively supported by the gears (16, 22) are arranged at positions meshing with the main gear (31), and the feeding means (1) and the plurality of conveying means (
13, 20), there is a U-turn conveyance path (
27, 29).

[0010] Also, in the U-turn conveyance path (27, 29
) is transported by other feeding means (P1, P2)
It has a conveyance port (27c, 29c) that can be merged.

[0011] Furthermore, the U-turn conveyance path (27, 29)
a paper detecting means (26) disposed on the most downstream side of the paper (P) to detect the leading edge of the paper (P); and a detection signal from the paper detecting means (26) to stop the drive of the drive source (M); , and registration control means (4) for restarting the drive source after a certain period of time.

0012

[Operation] Based on the above configuration, when the drive source (M) is driven, the drive is transmitted to the main gear (31), and this rotation is further transmitted to the driven gear (11) of the feeding roller (3) and the first The driven gear 16 of the conveying means (13), the second conveying means (2
0) is transmitted to the driven gear (22). At this time, even if the driven gear (11) rotates, the drive control mechanism (12) is controlled so that no driving force is transmitted to the drive shaft (3a), so the feeding roller (3) does not rotate. The two transport means are rotating. The drive control mechanism (12) couples the rotation of the driven gear (11) to the drive shaft (3a), thereby rotating the feeding roller (3) and feeding the paper (P). Furthermore, the paper (P) is conveyed through the U-turn conveyance path (16, 22) by the conveyance force of the first conveyance means (13) and the second conveyance means (20). As a result, one main gear (31) can drive the feeding roller (3) and the plurality of conveying means (13, 20), and the driving source (
It becomes possible to reduce the number of gears for transmitting the driving force of M).

Note that the above-mentioned symbols in parentheses are shown for reference to the drawings and do not limit the structure of the present invention in any way.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described below with reference to FIGS. 1 to 4.

[First Embodiment] In FIG. 1, the device main body 8
The paper stacking device 6 disposed inside is composed of a stacking table 2 on which paper P is stacked, and an elastic member 5 that biases the paper P against a feeding roller, which will be described later. The feeding means 1 is rotatably supported by a drive shaft 3a and rotates in the direction of the arrow to feed the paper P on the loading table 2.
It consists of a feeding roller 3 that feeds the sheets P, and a separating means 10 that separates the fed sheets P one by one. The separating means 10 includes a friction member 7 that separates the paper P, and an elastic member 9 that urges the friction member 7 against the feeding roller 3.

A driven gear 1 is provided at one end of the drive shaft 3a.
1 and an electromagnetic clutch 12 are provided, and by turning on/off the electromagnetic clutch 12, the drive shaft 3 is connected from the driven gear 11.
It is possible to connect and release the drive to a.

[0017] On the downstream side of the feeding means 1, a first conveying means 13 is arranged. This first conveying means 13 is composed of a roller 15 and a driven gear 16 made of a friction member that are supported on a support shaft 15a, and a driven roller 19 that is urged against the roller 15 by an elastic member 17. There is. On the downstream side of the first conveying means 13, a second conveying means 2 is provided.
0 is placed. This second conveying means 20 is composed of a roller 21 made of a friction member supported by a support shaft 21a, a driven gear 22, and a driven roller 25 urged against the roller 21 by an elastic member 23. ing.

A paper transport path 30 consisting of guide plates 30a and 30b is formed on the downstream side of the second transport means 20, and in the vicinity of the second transport means 20 in this paper transport path 30, A paper detecting means 26 consisting of a photo interrupter is provided to detect the leading edge of the paper P.

Between the feeding means 1 and the first conveying means 13,
A paper transport path 27 is formed by guide plates 27a and 27b for guiding the paper P, and the first transport means 13
and a guide plate 29a provided between the second conveyance means 20,
A paper conveyance path 29 is formed by 29b. Each guide plate 27a, 27b, 29a, 29b, 30a, 30b formed across the feeding means 1 and the second conveying means 20
U-shaped paper conveyance paths 27, 29, and 30 are formed by these.

A main gear 31 is connected to the drive source M via a gear train (not shown), and each of the driven gears 11, 16, 22 is arranged so as to mesh with the main gear 31. has been done. As the main gear 31 rotates in the direction of the arrow, each gear 11, 16, 22 rotates in the same direction as shown by the arrow. In addition, the feeding roller 3
The numbers of teeth of the gears 11, 16, and 22 are determined so that the circumferential speed of the rollers and the circumferential speeds of the two rollers 15 and 21 are constant.

Next, the operation of the paper conveying device will be explained with reference to FIGS. 2 to 4. In FIG. 2, it is assumed that the electromagnetic clutch 12 is not energized and the driven gear 11 is in a state where it can freely rotate with respect to the drive shaft 3a. When the drive source M is driven, the drive is transmitted to the main gear 31 and further to the driven gears 11, 16, and 22. At this time, even if the driven gear 11 rotates, the driving force is not transmitted to the drive shaft 3a, so the feeding roller 3 does not rotate. Since drive is transmitted to the two support shafts 15a and 21a, the rollers 15 and 21 are rotating, respectively.

[0022] Here, when the electromagnetic clutch 12 is energized,
The drive of the driven gear 11 is transmitted to the drive shaft 3a, and the feeding roller 3 rotates in the direction of the arrow. Then, the uppermost paper stacked on the paper stacking device 6 is fed, and only the uppermost paper P1 is separated by the separating means 10 and enters the paper transport path 27 (see FIG. 3). Furthermore, the paper P1 is transferred to the feed roller 3
, the paper advances to the paper transport paths 29 and 30 due to the transport forces of the first transport means 13 and the second transport means 20, but the electromagnetic clutch 12 is activated by the first transport means even if the leading edge of the transported paper P1 is fast. 13, or until the feeding roller 3 comes into contact with the next sheet P at the latest, the current is energized.

When the leading edge of the paper P1 is detected by the paper detection means 26, the driving source M is stopped, the rotation of each roller is stopped, and the paper P1 is temporarily put on standby (see FIG. 4). After a certain period of time after the stop, the drive source M is restarted under the control of the registration control means 4, and the paper P1 is further conveyed. In this way, the sheets of paper P are fed one by one while being timed.

[Embodiment 2] FIG. 5 shows a second embodiment of the present invention. In the first embodiment, the paper P is loaded on the loading table 2 in the device main body 8, but the paper P can also be loaded in a removable cassette 33 in the device main body 8 as shown in FIG. good. Here, reference numeral 35 indicates a cassette main body, and a loading table 37 housed therein is urged by a pressure spring 36 to urge the paper P against the feeding roller 3.

[Embodiment 3] The feeding means of the first embodiment is as follows:
Although this paper feeding method uses a frictional separation method, the paper P may be separated by a claw separation method as shown in FIG. Separation claws 40 come into contact with both corners of the paper P and separate the uppermost paper P1 when the paper P is fed. The feeding roller 41 has a half-moon shape in cross section. Further, the driven roller 19 of the first conveying means 42 and the driven roller 25 of the second conveying means 43 are oblique conveying rollers disposed so that their rotation axes are oblique to the rollers 15 and 21 on the driving side. A configuration may also be used. The feeding roller 41 is controlled one rotation by a drive control means 12 provided on a drive shaft 41a. At this time, the feeding roller 4
It is assumed that the arc length of 1 is sufficiently longer than the distance from the leading edge of the paper P to the first conveying means 42.

[Embodiment 4] FIG. 7 shows a fourth embodiment of the present invention. In the figure, a paper transport path 27 between the feeding roller 3 and the first transport means 13 and a paper transport path 29 between the first transport means 13 and the second transport means 20 are provided with other feeding means. Paper P1 and paper P fed from (not shown)
Feeding ports 27c and 29c, which can be connected to each other, are provided in such a manner that they are connected to each other. This makes it possible to feed paper from a plurality of paper stacking units.

[Embodiment 5] In the first embodiment, the drive control mechanism for the feeding roller 3 is performed by the electromagnetic clutch 12, but this can be changed to, for example, using a solenoid 50 and a spring clutch 51 as shown in FIG. Any configuration is acceptable. In the figure, since the actuator 50a of the solenoid 50 locks the pawl portion 52a of the control ring 52 that constitutes the spring clutch 51,
The feeding roller 3 is in a state of idle rotation. solenoid 5
0 momentarily, the actuator 50a moves the claw portion 52.
When the feed roller 3a is removed from the drive shaft 3a, the drive is connected, the drive shaft 3a rotates, and the feeding roller 3 starts rotating. Feeding roller 3
When the actuator 50a rotates exactly once, the actuator 50a engages the claw portion 52.
By locking a, the feeding roller 3 is stopped.

Furthermore, as shown in FIG. 9, a solenoid 50
The feeding roller 3 may be controlled by using a spring 59 whose one end is locked to the pin 57 of the control ring 56 and by providing a notch 11a in a part of the driven gear 11. A claw portion 56a and a pin 57 are integrally formed on the driven gear 11, and a solenoid 50
The actuator 50a locks the claw portion 56a. One end of the spring 59 is engaged with the pin 57, and the other end is engaged with the main body fixing portion, urging the feeding roller 3 to rotate in the direction of the arrow.

The driven gear 11 has some of its teeth cut out, and maintains a state in which it does not mesh with the main gear 31 as shown in the figure. Therefore, when the solenoid 50 is energized momentarily, the actuator 50a separates from the claw portion 56a, and the spring 5
The driven gear 11 rotates slightly in the direction of the arrow due to the biasing force 9. Due to this rotation, the notch portion 11a of the driven gear 11 moves and comes to mesh with the main gear 31, thereby transmitting the drive of the main gear 31. When the driven gear 11 rotates once, the claw portion 56a is stopped by the actuator 50a.

[0030]

[Effects of the Invention] As explained above, according to the present invention,
The feeding roller that feeds the stacked paper and the rollers of the plurality of conveyance means downstream thereof can be rotated by one main gear connected to a drive source, so that the feeding roller and the conveyance Since the number of gears that transmit driving force to the means is reduced, costs can be reduced and the device can be made more compact.

Furthermore, by providing the U-turn conveyance path with a feeding port that joins from other feeding means, it becomes easy to connect paper paths from other feeding means (circumferential, manual feeding, etc.). Further, since the plurality of conveyance means can be arranged in the U-turn conveyance path, the paper loading device can be housed within the apparatus main body, and the installation area of the apparatus main body can be reduced.

[Brief explanation of drawings]

FIG. 1 is a longitudinal side view showing a first embodiment of the present invention.

FIG. 2 is also an action diagram.

FIG. 3 is an action diagram as well.

FIG. 4 is also an action diagram.

FIG. 5 is a longitudinal sectional side view of a paper conveyance device showing a second embodiment of the present invention.

FIG. 6 is a longitudinal sectional side view of a paper conveyance device showing a third embodiment of the present invention.

FIG. 7 is a longitudinal sectional side view of a paper conveyance device showing a fourth embodiment of the present invention.

FIG. 8 is a longitudinal sectional side view of a paper conveyance device showing a fifth embodiment of the present invention.

9 is a vertical sectional side view showing a modification of the device shown in FIG. 8. FIG.

FIG. 10 is a longitudinal sectional side view of a paper conveyance device showing an example of a conventional paper conveyance device.

[Explanation of symbols]

P, P1, P2 Paper 1 Feeding means 2 Loading table 3 Feeding roller 3a Drive shaft 4 Registration control means 8 Apparatus body 11 Driven gear 12 Drive control mechanism (electromagnetic clutch) 13
First conveyance means 15 Drive roller 16 Driven gear 19 Driven roller (or oblique feeding roller) 20
Second conveyance means 21 Drive roller 22 Driven gear 25 Driven roller (or oblique feeding roller) 27, 29
, 30 U-turn conveyance path 31 Main gear

Claims (4)

[Claims] 1. Feeding means comprising a feeding roller that feeds stacked and stored sheets one by one and a drive control mechanism that controls rotation of the feeding roller, and a feeding means provided on the downstream side of the feeding roller. a plurality of conveying means each including a pair of conveying rollers arranged in sequence and conveying the paper fed by the feeding roller; and a driving source for driving the feeding roller and the conveying means, the drive being transmitted by a drive source. a main gear, a driven gear pivotally supported on the drive shaft of the feeding roller of the feeding means, and a driven gear supported on the drive shaft of the roller of each of the conveying means, A paper conveyance device, characterized in that a U-turn conveyance path for guiding the paper is disposed at a position meshing with the main gear, and between the feeding means and the plurality of conveyance means. 2. The conveying means is a pair of diagonal feeding rollers comprising a driving roller made of a friction member and a diagonal feeding roller pressed against the driving roller by an elastic member. Paper transport device. 3. The paper conveyance device according to claim 1, wherein the U-turn conveyance path has a conveyance port through which sheets conveyed by other feeding means can merge. 4. Paper detecting means disposed on the most downstream side of the U-turn conveyance path to detect the leading edge of the paper; and a detection signal from the paper detecting means to stop the drive of the drive source and to control the drive source at a constant speed. Claim 1, further comprising a resist control means for restarting the drive source after a certain period of time.
The paper transport device described.