JPH03186541A - Sheet transporting device - Google Patents

Abstract

PURPOSE:To easily separate two rotary members for nipping a sheet from each other by installing a means for separating the second rotary member from the first rotary member against the pulling force of a spring means through a process of substantially attaching the second rotary member to a prescribed regulating member. CONSTITUTION:When a driven roller 33 turns around a driving roller 32, a triangle having apexes at a center axis 40, axis 42, and a driven roller shaft 44 turns, keeping the same shape, by the pulling force of a spring 45. Accordingly, since a member bulging out from the outer periphery of the driven roller 33 does not exist, other member can be arranged on the peripheral part, and the whole of the device can be made compact. Further, if a turning driving power is applied after the shaft 44 of the driven roller 33 contacts a stopper member 46 installed on the peripheral circuit, the shaft 44 of the driven roller 33 shifts along the contact surface of the stopper member 46 against the pulling force of the spring 45. Accordingly, the driven roller 33 is separated from the driving roller 32 in the direction crossing the sheet transport direction.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a sheet conveying device that is used in a recording device, a reading device, or the like, and has a mechanism for changing the traveling direction of a sheet.

[Prior Art] Conventionally, in order to change the course of a sheet being conveyed along a certain conveyance path and convey it to another path, it was necessary to use a movable guide plate, etc. There was a fear that the sheet surface curved along the guide plate having a small radius of curvature would rub against the guide plate and damage the emulsion surface of the sheet surface.

Therefore, in order to solve this problem, the applicant of the present application proposed in the previously filed Japanese Patent Application No. 1-169425 that the traveling direction of the sheet being conveyed while being held between two rotating members can be changed to an arbitrary direction. We have proposed a compact sheet conveying device that can

[Object of the Invention] The object of the present invention is to further improve the sheet transport device proposed above, and to provide a sheet transport device that can separate the two rotating members that sandwich the sheet with a simple configuration. It is something to do.

[Means for Achieving the Object] The present invention that achieves the above object provides a sheet conveying device that grips a sheet between first and second rotating members, at least one of which has a rotational driving force, and conveys the gripped sheet. , a tensioning means for applying a tensile force between the first rotating member and the second rotating member; and a tensioning means for bringing the second rotating member into substantially contact with a predetermined regulating member. The sheet conveying device is characterized by having means for separating the second rotating member from the first rotating member against a force.

[Example] Hereinafter, an example applied to an image recording apparatus that records an image by scanning a light beam on a photosensitive sheet film will be described in detail. Note that the scope of application of the present invention is not limited to image recording devices, but can be widely applied to devices having a sheet conveyance mechanism for conveying a sheet-like member, such as an image reading device, a copying device, and a photographing device.

FIG. 1 is a configuration diagram of an embodiment of the present invention. In the figure, 1 is a laser beam unit, which has a laser light source, a light modulator, a polygon mirror, etc., and emits a laser beam modulated according to an image signal. 1a is deflected in the main scanning direction using rotation of a polygon mirror, and the film surface at the recording position is optically scanned. Note that while the sheet is being fed, a shutter (not shown) or the like is used to prevent the laser beam from being irradiated onto the recording position. A sub-scanning roller 2 is arranged below the laser optical system 1, and the sub-scanning roller 2 is a pair of rollers, one of which has a rotational driving force and the other is driven by it, and the sheet sandwiched between the two rollers is It is conveyed at a constant speed to perform sub-scanning for image recording. A laser beam 1a from a laser optical system 1 is optically scanned in the vicinity of the sub-scanning roller 2.

Below the sub-scanning roller 2, a supply magazine 3 that stores unrecorded sheets in a stacked manner from the bottom and a receive magazine 4 that stores recorded sheets are arranged in parallel. Each magazine 3.4 is provided with slide lids 3a and 4a that can be opened and closed for loading and unloading sheets, and the slides 1i3a, 4a are provided on the top surface of each magazine.
With 4a closed, the inside of the magazine is shielded from light from the outside. Note that the sheet films laminated inside both magazines 3 and 4 have their film emulsion surfaces facing downward to further enhance the light-shielding effect. It is provided for taking out one sheet at a time from the magazine opening.

Drive rollers 12.22.3 each with rotational driving force
2 and driven rollers 13, 23, and 33 having no driving force form first, second, and third conveyance roller pairs, respectively. These three conveyance roller pairs are driven by one motor via a chain, and the number of teeth of each sprocket is determined so that the circumferential speeds of the rollers are all the same. The driven roller 13 near the sheet ejection port is equipped with a mechanism that can reciprocate between positions G and H in the figure, and in the initial state it is retracted to the G position, and when it moves to the H position, it comes into contact with the driving roller 12 while being urged. . The driven roller 23 is similarly movable from position J, and is retracted to position J in the initial state. Further, the driven roller 33 is movable in each position of P, Q, R, and S.
In the initial state, a roller pair is formed at the Q position, and P, Q
.

At the position between R, the roller moves planetarily while contacting the drive roller 32.

Reference numeral 14 denotes a pair of pinching rollers, which are composed of two lightly biased rollers that are freely rotatable and do not have a driving force. Reference numeral 15 denotes a resist plate, which is moved from position M to L with 15c at the center to push the film held by the pair of nipping rollers 14, align the inclination of the sheet, and remove the resist. In addition, the guide surface 15b is designed to serve as a conveyance guide with less resistance during sub-scanning.
is smooth. 24 and 34 are film guide plates, and 36 is a guide roller, which guides the conveyed film. The guide plate 34 is slightly curved in the direction of gravity with respect to the tangential direction of the pair of sub-scanning rollers 2 to reduce sheet conveyance resistance during sub-scanning. Also, the movable guide plate 35 is normally retracted to the V position, but it is retracted to the W position during sub-scanning.
The drive roller 32 is raised to the position shown in FIG. Each guide plate has a smooth surface to reduce conveyance resistance.

When the leading edge of the sheet taken out from the supply magazine 3 reaches the sub-scanning roller pair 2, the trailing edge of the sheet is still held between the first m2 feed roller pair 11.

Hereinafter, the path through which the sheets taken out from the supply magazine 3 are fed to the guide plate 34 will be referred to as a first conveyance path, and the path from the lower end of the guide surface 15b of the resist plate 15 at the L position to the guide plate 34 will be referred to as a second conveyance path. We will call it the conveyance path. The first conveyance path and the second conveyance path share a path from the J position of the driven roller 23 to the guide plate 34.

Next, the operation of the image recording apparatus having the configuration described above will be explained.

The supply magazine 3 in which unrecorded sheets are stacked and stored is loaded at a predetermined position within the main body of the apparatus, and the slide M3a cannot be opened while the inside of the apparatus is shielded from light. Next, the suction cup 5 is operated to suck the topmost one of the sheets stacked in the supply magazine 3 at position E in the figure and lift it to position F.

At this time, the tip of the lifted sheet comes into light contact with the drive roller 12. Next, the driven roller 13, which had been retracted to the position G, enters the position H, and the driving roller 1
Insert the tip of the sheet between 2 and 2. In this state, the suction of the suction cup 5 is stopped, the suction cup 5 is released from the sheet, and the drive roller 12
When the sheet is conveyed in six directions by rotating clockwise, the conveyed sheet is inserted into the pair of pinching rollers 14 arranged in the sheet advancing direction, and the sheet advances in the tangential direction of the pair of pinching rollers 14. When the leading edge of the sheet reaches a predetermined position a little beyond the nipping roller pair 14, the rotation of the driving roller 12 is stopped and the driven roller 13 is retracted to the G position again. In this way, one sheet taken out is held by the nipping roller pair 14 by weak friction.

Next, when the resist plate 15 moves from the M position to the blank position in this state, the resist surface 15a hits the leading edge of the sheet and pushes the sheet back in the B direction opposite to the traveling direction against the weak holding force of the nipping rollers 14. In this way, the leading edge of the sheet is aligned along the registration surface 15a, and registration operations for correcting the sheet inclination and positioning are performed.

After the resist operation is completed, the resist plate 15 is returned to the initial position M.
Return to Then, the driving roller 12 is driven to advance the sheet to a predetermined position past the upper part of the driven roller 23 waiting at the K position, and then the driving roller stops. Next, the driven roller 23
The sheet is moved from the crab position to the J position, the sheet is curved, and the leading edge of the curved sheet is moved between the driving roller 22 and the driven roller 23.
Insert it in between. The drive rollers 22 and 12 are then rotated to advance the sheet along the guide plate 24 in the C direction.

When the leading edge of the conveyed sheet is inserted between the third pair of conveying rollers consisting of the driving roller 32 and the driven roller 33 at the Q position, the driven roller 33 will move the driving roller 32 with the sheet sandwiched between them.
The conveying sheet is rotated around the sheet conveying speed at a constant speed to the R position, and the traveling direction of the leading edge of the conveyed sheet is changed to the right in the figure. By stopping and fixing the rotation of the driven roller 33 at the R position and continuing to rotate the drive roller 32, the sheet advances along the guide plate 35 and is inserted between the pair of sub-scanning rollers 2.

When the sheet is fed until the rear end of the sheet is removed from the nipping roller pair 14, the resist plate 15 moves to the L position, and a guide surface 15b in the same direction as the guide plate 24 is formed. The path formed by the guide plate 24 and the guide surface 15b is a straight path with little conveyance resistance.

Here, each pair of conveyance rollers and each pair of sub-scanning rollers all rotate in the opposite direction. As a result, the sheet descends in the D direction along the guide plate 24 and the guide surface 15b.

When the edge of the sheet is removed from the sub-scanning roller pair 2, the driven roller 23 moves from the S position to the S position, and the sheet holding action of the second conveyance roller pair is released.

Next, each conveyance roller rotates normally again, and the sheet is conveyed in the forward direction by the third conveyance roller pair. When the leading edge of the sheet reaches the sub-scanning roller 2 that rotates in the forward direction in the sub-scanning direction, and the leading edge is sandwiched between the pair of sub-scanning rollers 2,
At the same time, the driven roller 33 separates from the driving roller 32 and S
The drive roller 32 is retracted to the position , and the drive roller 32 stops rotating. At the same time, the movable guide plate 35, which had been retracted to the V position,
The movable guide plate 35 moves upward to the position W to release the sheet from the surface of the driving roller, and the movable guide plate 35 functions as a conveyance guide during sub-scanning.

After this, when sub-scanning of the sheet is started by the sub-scanning roller 2, a laser beam is emitted from the laser optical system 1 to perform main scanning on the sheet, and an image is formed on the emulsion surface on the upper surface of the sheet as shown in FIG. A latent image is recorded. When recording is completed, the trailing edge of the sheet is held between the sub-scanning rollers, and the recorded portion is discharged along the guide plate 34.

The sheet that is sub-scanned along the second conveyance path is curved along the outer periphery of the movable guide plate 35, but the curvature in this part is caused by the repulsive force of the bending of the flexible sheet and the force of the sheet hanging down due to the guard. This is a curvature close to the natural state in which they cancel each other out. Further, in other parts of the second conveyance path, the sheet is not curved and maintains a natural state, so there is little friction between the sheet and the rollers and guide plates. Comparing this second conveyance path with the first conveyance path through which sheets taken out from the supply magazine 3 are conveyed, the rear ends of the sheets conveyed like the first conveyance path are stacked and stored in the supply magazine. Because there is no large frictional resistance due to close contact with the laminated sheet to be carried due to static electricity, etc., and the curvature of the sheet conveyance path is not sharp, the first
The second conveyance path has extremely low conveyance resistance compared to the second conveyance path. As a result, sub-scanning can be performed at a stable feed rate with little fluctuation, and high-quality image recording without unevenness is possible.

After the recording is completed, the sub-scanning roller 2 is rotated in the reverse direction to convey the recorded sheet in the opposite direction to that during recording. When the trailing edge of the sheet reaches the drive roller 32, move the movable guide plate 35 to V.
The driven roller 33, which had been returned to the S position, is also moved back to the R position.
Return to position and hold the rear end of the sheet between the rollers. Then, while the end portion of the sheet is being held, the driving roller 32 rotates and the driven roller 33 rotates to the P position, changing the direction in which the sheet advances toward the inside of the receive magazine 4.

Then, by continuing to drive the drive roller 32, the recorded sheet is fed into the receive magazine 4. After this, the driven roller 33 returns to the initial position Q. Note that the number of sheets already stored in the receive magazine 4 is recognized by means not shown, and the stacking height of the sheets in the receive magazine is estimated based on the number of sheets, and the sheets are placed in the optimal position according to the height. The stopping position P of the driven roller 33 is determined. This allows recorded sheets to be fed into the receive magazine without malfunction regardless of the number of stacked sheets.

Also, although not shown, by changing the traveling direction of the recorded sheet using the sheet traveling direction changing action of the third pair of transport rollers, image recording can be performed without storing the recorded sheet in the receive magazine. It is also possible to directly discharge and feed to an automatic developing device or the like provided outside the apparatus. In this case, when recording on the sheet is completed, the driven roller 33 is fixed at the R position so that the sheet advances straight to the left in the figure, and the drive roller 32 continues to rotate counterclockwise to record the image. The finished sheet can be advanced along a guide plate (not shown), discharged from the discharge port 37, and fed to an automatic developing device or the like directly connected to the side surface.

Next, a detailed explanation of the sheet conveying apparatus according to the present invention, that is, the unit of the third pair of conveying rollers will be given with reference to FIGS. 3(a) and 3(b).

FIG. 3(b) is a side view of FIG. 3(a), which is a block diagram of the unit.

In the figure, reference numeral 40 denotes a center axis of planetary rotation in which the driven roller 33 orbits around the circumference of the drive roller 32 in a planetary manner, and a lever 41 is fixed thereto. Note that the center axis of the drive roller 32 and the planetary rotation center axis 40 are coaxial, and the drive roller 3 is driven by a driving force transmitted by a sprocket chain (not shown).
2 is rotatable in both directions. The lever 41 and the lever 43 are connected via a shaft 42 and are bendable. The lever 43 has a driven roller IIk44.
is rotatably mounted. Reference numeral 45 denotes a single-tension spring, which applies a tensile force between the central shaft 40 and the shaft 44 of the driven roller 33, thereby biasing the two rollers. Further, 46 is a stopper member attached to the side plate, and the driven roller shaft 44
is placed at a predetermined position on the circuit.

In the previous operation description, when the sheet is conveyed to the sub-scanning roller pair 2 by the third conveying roller pair and the leading edge of the sheet is held between the sub-scanning roller pair 2, the driven roller 3
3 is designed to retreat from R to S position. When the center shaft 40 is rotated clockwise in the figure, a force is applied to extend the lever 41 fixed to the center shaft 40 and the lever 43 connected to the center shaft 40 so as to be bendable. Normally, when the driven roller 33 revolves around the driving roller 32, the spring 45 rotates with the same shape without changing the shape of the triangle whose vertices are the central shaft 40, the shaft 43, and the driven roller @44. Therefore, since there is no member protruding from the outer periphery of the driven roller 33, other members can be placed around the periphery, and the entire device can be made compact.

Subsequently, after the shaft 44 of the driven roller comes into contact with the stopper member 46 mounted on the circumferential circuit, when further rotational driving force is applied, the shaft 44 of the driven roller resists the tensile force of the spring 45,
It moves along the contact surface of the stopper member 46. If the contact surface of the stopper member 46 is set in a direction that intersects with the sheet conveyance direction, the driven roller 33 will eventually separate from the driven roller 32 in the direction that intersects with the sheet conveyance direction.

Note that the above is an example in which the conveyance roller retracts so as not to apply a load to the sheet during the sub-scanning process.
The application of the device of the invention is not limited to this.

For example, a similar mechanism may be used to retract the rollers in order to temporarily unrestrict the sheet during registration.

Further, a similar mechanism may be used when a sheet is inserted into a pair of conveyance rollers. In other words, the rollers are temporarily evacuated,
The sheet end portion is inserted therein by the upstream feeding means. At this time, even if the sheet is warped and the edge of the sheet being inserted is lifted up, the roller is retracted, so the insertion range is wide, and there is less chance of the sheet leading edge getting stuck and causing jamming. . When conveying the sheet by contacting and holding the retracted rollers, the rollers are configured to move away from each other in a direction crossing the sheet conveyance direction and then come into contact with each other. becomes less likely to occur. In this way, reliable sheet pinching operation is possible.

In the above embodiment, the stopper member 46 is fixed to the side plate, but as a modified example, as shown in FIG. The driven roller can be separated at a desired position among the plurality of positions.

When the stopper member is fixedly installed as in the above-described embodiment, it becomes impossible for the driven roller, which performs planetary motion, to move past the position where the stopper is attached. This is not a problem if the sheet conveyance direction is determined in advance and the driven roller reciprocates at a certain fixed angle, but it is possible to pinch the sheet coming from any direction, change the direction of travel, and convey it in another direction. In this case, it is desirable that the driven roller 33 be configured to be able to rotate around the drive roller 32 over 360 degrees. To this end, a plurality of stopper members 46 are installed on the circumferential circuit of the driven roller 33 so as to be movable back and forth, and the stopper members are configured to enter at a position where the driven roller 33 is desired to be separated from the interlocking roller 32.

As a modification with an even greater degree of freedom, as shown in FIG. 5, the stopper member 47 is rotatably mounted on the same axis as the drive roller 32, and the stopper member 47 and the driven roller 33 are controlled to rotate independently. It becomes possible to separate the driven roller at this position.

The stopper member 47 is at the same center as the drive roller 32! 1t
It is rotatably mounted on the h40, and rotational driving force is provided by a dedicated drive source such as a motor. First, stopper member 4
7 is independently rotated and stopped at a desired position where the driven roller 33 is desired to be separated. Note that the stopper member 47 may be rotated before the driven roller 33 is rotated, or the two members may be rotated simultaneously. In order to prevent the stopper member 47 from coming into contact with the driven roller 33 while the stopper member 47 is moving around and hindering the movement, the stopper member 47 is moved in the opposite direction to the direction in which the driven roller 33 moves, or when the stopper member 47 is rotating. The driven roller 33 is controlled to move around in front of the driven roller 33. When the stopper member 47 reaches the desired position and stops, the driven roller 33 reaches the desired position and the driven roller 33 is directly applied with driving force and brought into contact with the stopper member 47. By this action, the driven roller 33 can be separated. In this way, the driven roller can be separated at any position within 360 degrees.

Next, a second, more simplified embodiment of the sheet conveyance device according to the present invention will be described. FIG. 6(a) and FIG. 6(b) are explanatory diagrams of the operation.

Unlike the previous embodiment, this embodiment does not use a bendable connecting member, but uses a wooden connecting member 49 to connect the drive roller 32 and the driven roller 33, which can move planetarily around the drive roller 32. Connect. Connecting member 49 and driven roller 33
The rotation shaft 44 of the driven roller 33 is fitted into an elongated hole provided in the connecting member 49, and the driven roller 33 can be separated from the driving roller 32 along the elongated hole. Further, a tension spring is applied between the rotating shaft 44 and the rotating shaft of the drive roller, and biases the space between the two rollers. Further, a tapered member 48 corresponding to the stopper member in the previous embodiment is provided at a predetermined position on the circumferential circuit of the driven roller 33.

In the above configuration, the driven roller 33 together with the connecting rod 49
When rotated around the drive roller 32 in the counterclockwise direction in the drawing, the tapered member 48 at a predetermined position and the rotating member 44 come into contact as shown in FIG. As shown in FIG. 6(b), the rotating shaft 44 rides on the tapered surface of the tapered member 48, and the driven roller 33 is separated in the direction along the elongated hole. Alternatively, the tapered member 48 may be moved clockwise to separate the driven roller 33.

It should be noted that in this embodiment as well, those skilled in the art will easily infer that there are several possible variations regarding the arrangement of the tapered member 48, as in the previous embodiment.

[Effects of the Invention] According to the present invention, there is provided a sheet conveying device that has a compact configuration and is capable of separating two rotating members that sandwich a sheet.

[Brief explanation of drawings]

1 and 2 are block diagrams of an embodiment in which the sheet conveying device of the present invention is applied to an image recording device, and FIG. 3(a) and FIG.
b) is a detailed view of the sheet conveyance unit according to the present invention, FIGS. 4 and 5 are modifications of FIG. 3, and FIG. 6(a),
FIG. 6(b) shows the second sheet conveyance unit according to the present invention.
This is a detailed diagram of the embodiment, and the main symbols in the diagram are: 32...driving roller, 33...following roller, 4
1.43...Bendable connection lever 45...
・Tension spring, 46... Stopper member, Figure 3 (shi) B, 32

Claims (5)

[Claims] (1) In a sheet conveying device that sandwiches a sheet between first and second rotating members, at least one of which has a rotational driving force, and conveys the sandwiched sheet, the first rotating member and the second rotating member a tensioning means for applying a tension between the tension members; A sheet conveying device characterized by having means for separating from a rotating member. (2) The sheet conveying device according to claim 1, wherein the first and second rotating members are connected at their centers with a bendable connecting member being bent. (3) The second rotating member is movable along the periphery of the first rotating member to change the traveling direction of the conveyance sheet held between the first and second rotating members. 1)
The sheet conveying device described. (4) The sheet conveying device according to claim 3, wherein the regulating member is fixed at a predetermined position on the circumferential path or is movable back and forth. (5) The sheet conveying device according to claim 4, wherein the regulating member is coaxial with the roller member, can revolve on the same path as the planetary member, and can be stopped at a predetermined position.