JP2001171870A - Winding device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a winding device capable of certainly detecting that length of a loose part where a discharge part discharged from an image forming device is loosened reaches a predetermined length even when a position of the loose part is different. SOLUTION: The winding device 60 comprises a movable unit 100 that contacts with the loose part 14 and moves responsive to the length of the loose part 14, and a detector 130 for detecting the movable unit 100 when the length of the loose part 14 reaches the predetermined length.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a recording medium,
The present invention relates to a winding device that winds a portion on which an image is formed and discharged (hereinafter, referred to as a discharged portion).

[0002]

2. Description of the Related Art Conventionally, in an image forming apparatus for forming an image on a recording medium of a large size (for example, A0 size or A1 size), generally, a roll-shaped recording medium in which a band-shaped recording medium is wound into a roll or a long recording medium is used. Recording medium is used. Such an image forming apparatus usually includes a winding device that winds a discharge portion. In such image forming apparatuses, a winding device provided in a printer or a plotter that employs an ink jet system usually loosens the discharge portion before winding the discharge portion to loosen the slack portion (hereinafter referred to as a slack portion). After the ink is dried, the slack portion is wound up.

[0003] Many winding devices of this type wind up a slack portion with the image surface on which an image is formed facing outward. In this case, when the slack portion becomes long and comes into contact with a floor or the like, dust or the like adheres and the image surface becomes dirty. The time until the ink dries differs depending on the material of the recording medium. Therefore, when the recording medium comes into contact with a floor or the like, a portion where the ink has not dried may remain. In this case, the portion where the ink is not dried may be rubbed against the floor or the like to disturb the image, or the floor or the like may be stained with the ink.

Therefore, in this type of winding device, a slack sensor for detecting a slack portion is disposed on the side where the discharge portion slackens in order to prevent the image from becoming dirty or disturbed. Thus, the slack portion is detected by the slack sensor and rolled up before coming into contact with the floor or the like.

[0005] A winding device of the type described above will be described with reference to FIG.

FIG. 13 is a side sectional view schematically showing a plotter combined with a winding device of the type described above.

Below the plotter 20, the plotter 20
A winding device 40 that winds a portion (discharge portion) where an image is formed on the recording medium and discharged (winding portion) around the winding shaft 42 is disposed. The plotter 20 is fixed to an upper part of the stand 30. The stand 30 includes a leg 34 with a caster 36 and an upright column 32 fixed to the leg 34. The plotter 2
0 is fixed.

[0008] The plotter 20 has a housing 22 in which the inside is hollow 22a. A platen 24 on which a recording medium is placed is fixed to an upper portion of the housing 22. The recording medium 10 wound in a roll shape is arranged behind the housing 22 (left side on the paper surface of FIG. 13). The recording medium 10 is pulled out in the direction of arrow A toward the recording medium insertion port 21, inserted into the recording medium insertion port 21, and placed on the platen 24.

Above the platen 24, a guide shaft 25 is extended parallel to the platen 24 (in a direction perpendicular to the paper surface). A carriage 26 is fixed to the guide shaft 25 so as to reciprocate. The carriage 26 reciprocates by a drive motor (not shown) and a belt (not shown) while being guided by the guide shaft 25.

A print head 28 for discharging ink is mounted on the carriage 26. The print head 28 has an ink ejection surface (not shown) on which a plurality of ink ejection ports for ejecting ink are formed. In front of the ink ejection surface is an image forming area where an image is formed, and ink is ejected from an ink ejection port to a portion of the recording medium 10 located in the image forming area to form an image.

In forming an image on the recording medium 10, the recording medium 10 placed on the platen 24 is transported by a transport roller 23 having a part of the outer peripheral surface exposed from an opening formed in the platen 24, 10 are pinched by pinch rollers 27 that press down from above, and transported by rotating transport rollers 23 by a transport motor (not shown).
The recording medium 10 being transported is temporarily stopped, and the recording medium 1 is stopped.
While the carriage 26 reciprocates above the position 0, ink is ejected from the ejection ports based on an image signal carrying image information transmitted to the print head 28, and a portion of the recording medium 10 located in the image forming area. To form an image for one band.

Thereafter, the recording medium 10 is conveyed by the width of one band and stopped, and while the carriage 26 is reciprocated again, ink is ejected from the ink ejection ports based on the image signal, and An image is formed in a portion newly located in the image forming area. By repeating such an operation, an image is formed on the recording medium 10. The portion on which the image is formed is ejected one band at a time.

By the way, a winding device 40 for winding the discharge portion 12 on which an image has been formed as described above is disposed below the front side of the housing 22 (right side on the paper surface of FIG. 13). The winding device 40 has a winding roller 42 around which the discharge portion 12 is wound. To start winding, the leading end of the discharge portion 12 is fixed to the winding roller 42.

Below the winding roller 42, two sensors 44 and 46 for detecting the slack portion 14 indicated by a solid line are arranged at different heights. Two sensors 44, 4
6 is a sensor for determining the timing to start winding the slack portion 14. The lower sensor 44 is a photoelectric sensor that reflects light emitted from the light emitting unit 44a with the reflector 45 and receives the reflected light with the light receiving unit 44b. The lower sensor 44 and the reflection plate 45 are arranged so that the slack portion 14 blocks light near the point B on the paper surface. When the slack portion 14 is detected by the lower sensor 44, the plotter 2
Since the controller (not shown) that controls 0 (or the winding device 40) controls the winding roller 42 to rotate in a predetermined direction (the direction of arrow D), the slack portion 14 starts to be wound.

The upper sensor 46 disposed above the two sensors 44, 46 is also a photoelectric sensor similar to the lower sensor 44, and emits light emitted from the light emitting section 46a to the reflection plate 4.
7, and is configured to receive the reflected light at the light receiving portion 46b. The upper sensor 46 is a sensor for determining the timing at which the winding of the slack portion 14 is stopped. A state in which the slack portion 14 is wound up by the winding roller 42 and shortened is indicated by a two-dot chain line as the slack portion 16. Whether the slack part 16 is at the point C on the paper,
When it is at a position lower than the point C, the light emitted from the light emitting section 46 a is blocked by the slack portion 16. In this state, the winding operation is continued.

However, when the winding progresses and the slack portion 16 rises above the point C on the paper surface, the light emitted from the light emitting portion 46a is not blocked by the slack portion 16 but is reflected by the reflecting plate 47 and is received by the light receiving portion 46b. Is received at. As a result, the winding roller 42 is controlled to stop its rotation, and the winding of the slack portion 16 is stopped.

After this stop, when the image forming operation is performed and the length of the discharge portion 12 increases again, the slack portion 14 also increases. As described above, when the slack portion 14 blocks light from the light emitting portion 44a again at the point B on the paper surface, the controller of the winding device 40 rotates the winding roller 42 again to start winding the slack portion 14. Control so that By repeating such an operation, the discharge portion 12 is wound around the winding roller 42.

[0018]

As described above, the conventional winding device 40 winds the discharge portion 12 with the image surface on which an image is formed facing outward. However, depending on the purpose of use of the recording medium on which the image is formed, it may be more convenient to wind the recording medium with the image side inside.

In order to wind the discharge portion 12 with the image surface inside, the winding roller 42 is rotated in the direction opposite to the direction of arrow D. In this case, the discharge portion 12 is loosened on the side opposite to the side where the discharge portion 12 is loosened when the image is taken up with the image surface facing outward. As a result, the upper sensor 46
In addition, since the slack portion 14 cannot be detected by the lower sensor 44 or the lower sensor 44, it cannot be controlled so that the slack portion 14 is appropriately wound.

Further, even when the image is wound with the image surface facing outward, the position of the slack portion 14 changes due to a difference in environmental conditions such as humidity and temperature at a place where the winding device 40 is installed. Further, the position of the slack portion 14 also changes depending on the difference in the material of the recording medium and the thickness of the discharge portion 12 already wound up by the winding roller 42. For this reason, the length of the slack portion when detected by the upper sensor 46 or the lower sensor 44 changes, so that the winding control is likely to be inappropriate.

Further, the stiffness of the recording medium may change depending on environmental conditions such as humidity and temperature of the place where the winding device 40 is installed. When the stiffness of the recording medium increases, the discharged portion 12 immediately after the image is formed and discharged may rise, and a part of the recording medium located in the image forming area may slightly float. As a result, the image quality may deteriorate.

The present invention has been made in view of the above circumstances, and has as its object to provide a winding device that can prevent a discharge portion from floating up which causes deterioration of image quality.

Still another object of the present invention is to provide a winding device capable of accurately detecting that the length of the slack portion has reached a predetermined length even if the position of the slack portion differs due to various causes. And

[0024]

According to a first aspect of the present invention, there is provided a take-up device which achieves the above object by loosening a long discharge portion discharged from an image forming apparatus for forming an image on a recording medium. A winding device for winding a slackened slack portion around a rotating winding shaft, comprising: (1) pressing means for pressing a slack portion from discharge to winding up from a non-image surface on which no image is formed. It is characterized by the following.

Here, the pressing means (2) the movable unit which changes its position according to the length of the slack portion while contacting the slack portion (3) detects the length of the slack portion based on the position of the movable unit It may be provided with a detecting means for performing the detection. .

The winding shaft is provided in both (4) a first rotation direction in which the image is formed with the image surface outside and a second rotation direction in which the image is formed with the image surface inside. It may rotate selectively in the rotation direction.

Further, (5) the movable unit may be provided with a rotating shaft concentric with the winding shaft and changing its position by rotating around the rotating shaft.

Further, the movable unit comprises: (6) a pair of rotating arms (7) which are arranged one at each of both ends in the longitudinal direction of the winding shaft and which rotate about a rotating shaft; And a rod-shaped member that connects the distal ends of the rotary arms and contacts the slack portion.

Further, (8) the winding device may include a rotation stopper for restricting the movable unit so that the movable unit rotates within a predetermined range.

Further, the movable unit has (9) an arc portion extending in an arc shape from the rotation arm in opposite directions along a circle formed around the rotation axis. May be characterized in that (10) an arc portion is detected when the length of the slack portion reaches a predetermined length, and the arc portion is disposed near the arc portion.

[0031]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the winding device of the present invention will be described with reference to the drawings.

The outline of the winding device of the present invention will be described with reference to FIGS.

FIG. 1 is a side sectional view showing a winding device mounted on an ink jet type image forming apparatus. FIG.
FIG. 2 is a side sectional view showing a winding device in the process of winding a recording medium. FIG. 3 is an exploded perspective view showing a movable unit of the winding device and members around the movable unit. FIG. 4 (a)
FIG. 4 is a front view showing the movable unit and the winding unit shown in FIG. 3. (B) is a front view showing a winding unit. FIG. 5A is a left side view illustrating the movable unit and members around the movable unit. (B) is a right side view showing the movable unit and its peripheral members. FIG. 6 is a side view showing the movable unit and members around it.

Here, as shown in FIG. 1, as an example of an ink jet type image forming apparatus (an example of an image forming apparatus according to the present invention), a plotter 20 for forming an image by discharging ink onto a recording paper 10 is used. Are listed. Plotter 20
Is fixed to the upper part of a column 32 fixed upright to a leg 34 with casters 36. Behind the plotter 20 (left side on the paper surface of FIG. 1), a recording paper (an example of a recording medium according to the present invention) 10 wound in a roll shape is mounted. The recording paper 10 is pulled out by a predetermined amount in the direction of arrow A toward the plotter 20.

A carriage 26 having a print head 28 for discharging ink onto the recording paper 10 is mounted on the plotter 20. A cover 9 having a curved surface curved downward is disposed in a region opposite to the roll-shaped recording paper 10 with the plotter 20 interposed therebetween. A portion 12 discharged from the plotter 20 after the image is formed (hereinafter, referred to as a discharged portion 12) is guided along the curved surface of the cover 9 with the image surface 18 on which the image is formed facing upward. Of the discharge portion 12, the slack portion 14 that hangs down from the cover 9 and is loose is wound by the winding device 60.

This winding device 60 is, as shown in FIG.
A winding unit 90 for winding the slack portion 14 into a roll while rotating, a drive unit 140 for applying a rotational force to the winding unit 90, and a slack portion 14 which comes into contact with the slack portion 14 (see FIG. 2). The movable unit 100 changes its position and posture in accordance with the length of the movable unit 100, and a detector 130 for detecting the movable unit 100. The movable unit 100 and the detector 130 among these are examples of the pressing means according to the present invention.

Hereinafter, each of these units and the detector 130
Will be described.

The winding unit 90 is, as shown in FIG.
It has a cylindrical winding shaft 92 extending in the reciprocating direction of the carriage 26 (see FIG. 1) (direction perpendicular to the plane of FIG. 1).
Both ends of the winding shaft 92 are partially cut off so as to have a D-shaped cross section as shown in FIG. 4B (the front end 92a and the rear end 92b).

As shown in FIGS. 3 and 4, a cylindrical spool 94 is detachably fitted and fixed to the leading end 92a of the winding shaft 92. The spool 94 has a large-diameter cylindrical portion (hereinafter, referred to as a large-diameter cylinder) 94a.
And a cylindrical portion (hereinafter, referred to as a small-diameter cylinder) 94b having a smaller diameter than the large-diameter cylinder 94a.
The small-diameter cylinder 94b has a large-diameter cylinder 9
Cut 9 cut in parallel to winding shaft 92 toward 4a
5 are formed. The cut 95 includes the discharge portion 12.
One side of the tip is inserted and fixed. A screw hole 98a is also formed in the large-diameter cylinder 94a. The spool 94 is fixed to the winding shaft 92 by a screw 98b screwed into a screw hole 98a.

The leading end 92a of the winding shaft 92 is inserted from the small-diameter cylinder 94b toward the large-diameter cylinder 94a, and the foremost part of the leading end 92a protrudes from the large-diameter cylinder 94a. On the other hand, a cylindrical spool 96 is also detachably fitted and fixed to the rear end portion 92b of the winding shaft 92. The spool 96 is also formed by two portions having different diameters. Of these, the outer diameter of the cylindrical portion 96b having a small diameter (hereinafter referred to as a small-diameter cylinder) 96b
Is the same as the outer diameter of the small-diameter cylinder 94b. Small diameter cylinder 96b
A cut 97 is formed in the same manner as the cut 95. A screw hole (not shown) is formed on the outer peripheral surface.
This cut 97 has a cut 9 out of the tip of the discharge portion 12.
The part on the side opposite to the one side inserted in 5 is inserted and fixed.

The rear end 92b of the winding shaft 92 is inserted from the small-diameter cylinder 96b toward a large-diameter disk-shaped portion (hereinafter, referred to as a large-diameter disk) 96a.
The rear end of b protrudes from the large-diameter disk 96a. The spool 96 is fixed to the winding shaft 92 by a screw 84 screwed into a screw hole formed in the small diameter cylinder 96b.

The end faces of the small-diameter cylinder 94b and the small-diameter cylinder 96b of the spool 94 and the spool 96 fixed to the winding shaft 92 as described above face each other.
The spool 94 and the spool 96 have respective cuts 95,
Take-up shaft 92 so that the positions of
It is fixed to. As a result, when the distal end of the discharge portion 12 is inserted into the cuts 95 and 97 and fixed, the width direction of the discharge portion 12 (the direction orthogonal to the direction in which the discharge portion 12 is discharged) is taken up by the winding shaft 92. Becomes almost parallel to

As shown in FIG. 4A, a cylindrical rotation holding cylinder 93 is arranged concentrically with the spool 94 near the large-diameter cylinder 94a of the spool 94. This rotation holding cylinder 9
At one end of the three ends near the large-diameter cylinder 94a, an insertion hole 93a having substantially the same shape as the contour of the leading end 92a of the winding shaft 92 is formed. The distal end of the tip 92a is inserted into the insertion hole 93a. This allows
The tip 92 a of the winding shaft 92 is supported by the rotation holding cylinder 93.

A cylindrical insertion hole 93b is formed concentrically with the insertion hole 93a at the other end of the rotation holding cylinder 93 opposite to the one end. On the inner surface forming the insertion hole 93b,
A treatment for reducing frictional resistance is performed.

On the other hand, also in the vicinity of the large-diameter disk 96a of the spool 96, a cylindrical rotation holding cylinder 99 is arranged concentrically with the spool 96. At one end of the rotation holding cylinder 99 near the large-diameter cylinder 94a, a rear end 92b of the winding shaft 92 is provided.
An insertion hole 99a having substantially the same shape as that of the outline is formed. The rear end portion of the rear end portion 92b is inserted into the insertion hole 99a. A cylindrical insertion hole 99b is formed at the other end of the rotation holding cylinder 99 opposite to the one end.
It is formed concentrically with a. The winding unit 90 configured as described above is connected to the drive unit 140 (see FIG. 3) via the rotation holding cylinder 99.

The drive unit 140 includes, as shown in FIG. 3, an electric rotary motor 142,
A gear 144 fixed to the distal end of the output shaft 143, a gear 146 meshed with the gear 144, a drive shaft 148 fixed to one end of the gear 146, and the like.

The rotation direction of the rotation motor 142 can be selectively changed. The other end of the drive shaft 148 opposite to the one end is inserted into the insertion hole 99 b of the rotation holding cylinder 99. The surface of the other end is treated to reduce frictional resistance. The vicinity of the tip of the other end is fixed to the rotation holding cylinder 99 by a screw 82. This allows
The winding shaft 92 and the drive shaft 148 are concentrically connected.

Therefore, when the output shaft 143 is rotated by the rotation of the rotary motor 142, the drive shaft 148 is rotated via the gears 144 and 146. When the drive shaft 148 rotates, the winding shaft 92 rotates via the rotation holding cylinder 99. When the take-up shaft 92 rotates, the slack portion 14 of the recording paper 10, the tip of which is fixed to the spools 94 and 96, is taken up by the take-up shaft 92. Since the slack portion 14 is in contact with the movable unit 100 as shown in FIG.
When the length of the movable unit 100 is changed by winding, the position and the posture of the movable unit 100 change accordingly.

As shown in FIG. 3, the movable unit 100 includes a rotating arm 70 in the form of a plate that is long and slightly thick, a rotating arm 80 partially different in shape from the rotating arm 70,
A connecting rod (which is an example of a rod-shaped member according to the present invention) 110 for connecting the rotating arms 70 and 80, and a connecting rod 1
It is composed of a disk-shaped roller 112 rotatably fixed to and the like.

As shown in FIG. 4 (a), the rotating arm 70
It is rotatably fixed to the 0-side drive shaft 148 (which also serves as the rotation shaft according to the present invention). Rotating arm 70
5A, as shown in FIG. 5A, the width gradually decreases from the rear end 70b to the front end 70a. From both sides of a portion between the front end portion 70a and the rear end portion 70b of the rotary arm 70 and near the rear end portion 70b, arc portions 72 and 74 extending in opposite directions in an arc shape are formed. . The shape of the arc portions 72 and 74 is such that the rotation arm 70 rotates when the rotation arm 70 rotates about the drive shaft 148.
It is an arc along the circle drawn by the point M on the center line L of 0. The arc portions 72 and 74 are detected by the detector 130.

An insertion hole (not shown) is formed in the rear end 70b of the rotating arm 70, and the other end of the drive shaft 148 is inserted. The inner surface on which the insertion hole is formed is subjected to a treatment for reducing frictional resistance. As described above, the surface of the other end of the drive shaft 148 is also subjected to the process of reducing the frictional resistance, so that even if the drive shaft 148 rotates, the rotating arm 70 hardly rotates.

As shown in FIG. 4A, the rotating arm 80 is provided between the drive unit 14 and both ends of the winding unit 90.
It is fixed to a rotating shaft 86 to be described later in close proximity to the other end opposite to the one end close to zero. The rotating arm 80 is shown in FIG.
As shown in FIG.
However, the rotation arm 80 differs from the rotation arm 70 in that the rotation arms 80 do not include the arc portions 72 and 74 formed in the rotation arm 70.

An insertion hole (not shown) is formed in the rear end portion 80b of the rotation arm 80, and one end of the rotation shaft 86 passes through the insertion hole. The turning arm 80 is fixed to the turning shaft 86 by a screw 88. One end of both ends of the rotation shaft 86 is inserted into the insertion hole 93 b at the other end of the rotation holding cylinder 93. The surface of the portion of the rotary shaft 86 inserted into the insertion hole 93b is subjected to a process for reducing frictional resistance. On the other hand, the other end (not shown) of the rotating shaft 86 opposite to the one end is rotatably held by a bearing (not shown). Therefore, the winding shaft 92
Rotates, the rotation holding cylinder 93 also rotates.
No torque is transmitted to.

The distal end portion 80a of the rotating arm 80 has the structure shown in FIG.
As shown in (a), one end of the connecting rod 110 is fixed. The other end of the connecting rod 110 opposite to the one end is fixed to the tip end 70 a of the rotating arm 70.
Thus, the turning arm 70 and the turning arm 80 are connected. As shown in FIG.
A plurality of disk-shaped rollers 112 are rotatably fixed. The roller 112 is used for the discharge portion 12 (see FIG. 2).
Is in contact with and pressed against the slack portion 14. For this reason, even when a stiff recording sheet is used, the discharge portion does not rise, so that the position of the recording sheet during image formation does not change carelessly. In addition, the rotating arms 70 and 80, the connecting rod 110, and the roller 112 are made, for example, in a hollow shape or made of a lightweight material, so that the weight of the movable unit 100 is reduced.

As shown in FIG. 1, when the slack portion 14 reaches a predetermined length, one of the arc portions 72, 74 is provided near the arc portions 72, 74 of the rotating arm 70. A detector 130 (an example of a detecting unit according to the present invention, which is hereinafter referred to as an arc sensor 130) for detection is arranged. The detector 130 is fixed to, for example, a support on which the plotter 20 is mounted. In addition, the above-mentioned predetermined length means that the image surface 1
The length is such that the time until the ink No. 8 is sufficiently dried can be ensured, and the length does not reach the installation surface (for example, floor) of the plotter 20.

As shown in FIG. 2, an arc sensor 130 for detecting the arcs 72 and 74 of the rotary arm 70 is disposed below the drive shaft 148. This arc sensor 13
0 is a light emitting unit 130a that emits light as shown in FIG.
And a light receiving unit 1 for receiving light emitted by the light emitting unit 130a
The photoelectric sensor 30b faces the light emitting unit 130a and the light receiving unit 130b at a predetermined interval.

The arc portions 72 and 74 are, as shown in FIG.
When the position of the distal end portion 70 a of the rotating arm 70 is lowered, it passes vertically below the drive shaft 148. Therefore, the light emitting unit 130a
And the arc portions 72 and 74 enter the gap 132 between the light receiving portion 130b and the light receiving portion 130b. An arc sensor 130 is arranged at a position where the arc portions 72 and 74 that have entered can be detected. Note that an ultrasonic proximity switch can be used instead of the photoelectric sensor.

At a position vertically below the drive shaft 148 and higher than the arc sensor 130, the rotation of the rotation arm 70 is limited, and the rotation range of the movable unit 100 is set to a predetermined range (arrow). (A range of angles shown by I) is disposed. The rotation of the rotation arm 70 when rotating clockwise on the paper is restricted at a first position (position indicated by a solid line) in contact with the rotation stopper 120. On the other hand, the turning of the turning arm 70 when turning in the counterclockwise direction on the paper is restricted at a second position (position indicated by a two-dot chain line) in contact with the turning stopper 120. Therefore, the rotating arm 70 cannot rotate clockwise from the first position to the second position, and cannot rotate counterclockwise from the second position to the first position.

When the rotating arm 70 is at the first position,
The arc portion 72 is the gap 1 between the light emitting portion 130a and the light receiving portion 130b.
32, and the light emitted from the light emitting section 130a is blocked by the arc section 72. In addition, the rotating arm 7
0 is in the second position, the arc portion 74 is
The light enters the gap 132 between the light emitting portion 130a and the light receiving portion 130b, and the light emitted from the light emitting portion 130a is blocked by the arc portion 74.

The intersection P at which the longitudinal center line L from the front end portion 70a to the rear end portion 70b of the rotating arm 70 intersects the vertical line N is located at the center of the drive shaft 148. Assuming that the angle formed by the center line L when the rotating arm 70 is in the first position and the vertical line N in the clockwise direction is θ, when the rotating arm 70 is in the second position, The angle formed by the center line L and the vertical line N in the counterclockwise direction is also θ. If the angle θ is small, the movable unit 100 may not rotate smoothly. Therefore, the angle θ is preferably 30 ° or more.

As shown in FIG. 5B, the rotating arm 80
In order to limit the rotation range of the
A columnar rotation stopper 122 similar to that described above is disposed. The positional relationship between the rotation stopper 122 and the rotation shaft 86 is as follows.
The positional relationship between the rotation stopper 120 and the drive shaft 148 is the same. Thus, the rotation of the rotation arm 70 and the rotation of the rotation arm 80 are limited to the same range. Therefore, the rotation of the movable unit 100 is restricted within the above-mentioned predetermined range.

The movable unit 100 has a connecting rod 11
If there is 0, the roller 112 need not be provided. further,
The movable unit 100 may be a single member in which the rotating arms 70 and 80 and the connecting rod 110 are integrally formed.

With reference to FIGS. 1 and 2 again, a description will be given of a winding operation in which the winding device 60 configured as described above winds the slack portion 14 of the recording paper 10 around the winding shaft 92.

FIGS. 1 and 2 show an example of winding the slack portion 14 around the winding shaft 92 with the image plane 18 facing outward (outer winding). As shown in FIG. 1, when the rotating arm 70 is located at the first position, the rotating unit 120 is in contact with the rotating stopper 120 and the movable unit 100 is stationary. In addition, the slack portion 14 has reached a predetermined length.
In this case, the slack portion 14 is in light contact with the roller 112.

Note that a force for rotating the movable unit 100 in the direction of arrow G is constantly applied to the movable unit 100 by its own weight. When the rotation arm 70 is located at the first position, the arc portion 72 is
a and the gap 132 (see FIG. 3) between the light receiving portion 130b.

When the arc portion 72 enters the gap 132, the light emitted from the light emitting portion 130a is blocked by the arc portion 72, and the arc portion 72 is detected by the arc sensor 130. When the arc sensor 130 detects the arc portion 72, a controller (not shown) for controlling the entire plotter 20 (or the winding device 60) controls the rotation motor 142 (see FIG. 3), and the winding unit The take-up shaft 90 is rotated in the clockwise direction on the paper surface of FIG. 1 (an example of the first rotation direction in the present invention, which is the direction of arrow E). As a result, the slack portion 14 starts to be wound around the winding shaft 92 with the image surface 18 facing outward.

As the winding progresses, the slack portion 14 becomes shorter, and as shown in FIG.
00 rotates in the direction of arrow H. At this time, since the roller 112 that comes into contact with the slack portion 14 rotates freely, the movable unit 100 smoothly rotates and changes its position according to the length of the slack portion 14.

The controller controls the rotation motor 142 so that the rotation of the winding shaft 92 stops after performing a predetermined winding operation. For example, the rotation motor 142 is configured to stop when the rotation speed of the winding shaft 92 reaches a predetermined rotation speed.
Is controlled. In addition, the arc portion 7
The rotation motor 142 may be controlled so that the rotation of the winding shaft 92 stops when the light emitted from the light emitting unit 130a is received by the light receiving unit 130b when the light emitting unit 2 completely exits.

After the winding operation of the slack portion 14 is stopped as described above, the image forming operation is executed, and when the slack portion 14 reaches the predetermined length again, the predetermined winding operation is restarted. As described above, the execution and stop of the winding operation are repeated, and the slack portion 14 is wound on the winding shaft 92.

In order to remove the recording paper wound on the winding shaft 92 from the winding device 60, the rotating arm 80 is slid (in the direction of the arrow J), and the leading end 92a is pulled out of the rotation holding member 93. Next, the spool 94 is removed from the winding shaft 92, and the recording paper is pulled out (removed) from the winding shaft 92.

Referring to FIG. 7, a case where the slack portion 15 is wound with the image plane 18 inside will be described.

FIG. 7 is a side sectional view showing an example of a state in which the recording paper is wound with the image side inward by the above-mentioned winding device (inside winding). As shown in FIG. 7, the movable unit 100 (FIG. 3) is used for the inner winding and the outer winding.
(See Reference). In this case, the discharge part 1
A portion 15 (slack portion 15) hanging down from the cover 9 is loosened beyond the winding device 60 to the side where the rotating arm 70 is located (left side of the winding device on the paper surface of FIG. 7). It is. When the length of the slack portion 15 reaches the predetermined length, the rotation arm 70 is moved to the second position by the rotation stopper 12.
It is stationary in contact with 0. Since the rotating arm 70 is located at the second position, the arc portion 74 is detected by the arc sensor 130.
Is detected by

When the winding operation is performed, the rotating shaft 92 (FIG. 3 is an example of the second rotating direction in the present invention, which is an arrow F direction) on the paper surface of FIG. reference)
The controller controls the rotation motor 142 so as to rotate. In performing and stopping the winding operation, the inner winding is different from the outer winding in that the rotating shaft 92 rotates in the opposite direction, the position and posture of the rotating arm 70 are different,
Due to these differences, the arc detected by the arc sensor 130 is not the arc 72 but the arc 74
The only thing that is. Therefore, the description of the process in which the execution and stop of the winding operation are repeated and the slack portion 15 is wound on the winding shaft 92 will be omitted because it is the same as the above-described case of the outer winding.

Although the portions detected by the arc sensor 130 are arc-shaped arc portions 72 and 74, the shape is not limited to the arc shape, and the gap 13 between the light emitting portion 130a and the light receiving portion 130b is not limited to the arc shape.
2 (see FIG. 3) and may be a rectangular flat plate or a column such as a cylinder or a prism as long as the light emitted from the light emitting unit 130a can be blocked. Good.

With reference to FIGS. 8, 9, and 10, a winding device including a movable unit and a detector different from the above-described movable unit 100 and detector 130 will be described.

FIG. 8 is a side sectional view showing the winding device when the outer winding is performed. FIG. 9 is a side sectional view showing the winding device in the process of winding the slack portion. FIG.
FIG. 10 is a plan view showing a movable unit and a detector of the winding device shown in FIGS. 8 and 9. In these figures, the same components as those shown in FIGS. 1 to 4 are denoted by the same reference numerals.

As shown in FIGS. 8 and 9, the winding device 400
The movable unit 410 of the winding device 60 is the movable unit 1
00 (see FIG. 1) is that the rotation arm 412
Is different from the shape of the rotating arm 70. The rotating arm 412 includes an arc portion 7 formed on the rotating arm 70.
2, 74 (see FIG. 1) are not formed. Further, a vertically long columnar blocking member 480 is provided at the tip of the rotating arm 412.
Has been fixed. The longitudinal direction of the blocking member 480 is shown in FIG.
As shown in FIG. 0, the length of the connecting rod 110 coincides with the extension direction of the connecting rod 110 connecting the distal end 412a of the rotating arm 412 and the distal end 80a of the arm 80. The blocking member 480 is detected by two detection sensors 450 and 460 described later.

As shown in FIGS. 8 and 9, the two detection sensors 450 and 460 for detecting the blocking member 480 are arranged at different heights with the detection sensor 450 being higher. These detection sensors 450 and 460 are fixed to, for example, a support on which the plotter 20 is mounted.

The lower detection sensor 460 (hereinafter referred to as lower sensor 460) is a reflection type photoelectric sensor.
In the area where the ejection portion 12 is ejected from the plotter 300 (the area on the right side of the drive shaft 148 on the paper of FIGS. 8 and 9), a light emitting unit 462 for emitting light and the light emitting unit 4 are provided.
A light receiving unit 464 for receiving the emitted light of 62 is arranged. On the other hand, in the area where the recording paper 10 is wound in a roll shape (the area on the left side of the rotation axis 76 on the paper surface in FIGS. 8 and 9), the light emitted by the light emitting unit 462 is applied. A reflector 466 that reflects light toward the light receiving unit 464 is provided.

The lower sensor 460 determines the timing at which the winding operation of the slack portion 14 is started. Therefore, as shown in FIG. 8, when the slack portion 14 reaches a predetermined length and the rotating arm 412 reaches the first position,
The lower sensor 460 is disposed at a position where the light emitted from the light emitting unit 462 is blocked by the blocking member 480. As described above, the predetermined length is a length capable of securing a time required for the ink on the image surface 18 to be sufficiently dried by loosening the discharge portion 12 and the installation surface of the plotter 20 (for example, Floor).

The upper detection sensor 450 (hereinafter referred to as the upper sensor 450) is a reflection-type photoelectric sensor similar to the lower sensor 460. Light emitting unit 4 of host sensor 450
52, the light receiving section 454 and the reflector 456
The light emitting unit 462, the light receiving unit 464, and the reflector 466 are arranged in the same positional relationship.

The upper sensor 450 determines the timing at which the winding operation of the slack portion 14 is stopped. Therefore, as shown in FIG. 9, when the winding of the slack portion 14 progresses and the rotating arm 412 reaches the predetermined position, the upper sensor 450 causes the light emitted from the light emitting unit 452 to emit light by the blocking member 480. It is arranged at the position where it is cut off. Note that the predetermined position is the position of the rotating arm 412 when the slack portion 14 reaches the length when the winding operation is stopped.

Since the upper sensor 450 and the lower sensor 460 are arranged as described above, when the rotation arm 412 stops at the first position as shown in FIG.
Is detected by the lower sensor 460. When the lower sensor 460 detects the blocking member 480, a controller (not shown) that controls the entire plotter 300 (or the winding device 400) rotates the winding shaft 92 in the direction of arrow E (see FIG. (Not shown). As a result, the slack portion 14 starts to be wound around the winding shaft 92 with the image surface 18 facing outward. This rotation motor is the same rotation motor as the rotation motor 142 shown in FIG.

As the winding progresses, the slack portion 14 becomes shorter, and as shown in FIG.
10 rotates in the direction of arrow H. When the length of the slack portion 14 is shortened and the rotating arm 412 reaches the predetermined position, the blocking member 480 blocks light emitted from the light emitting section 452 of the upper sensor 450. When the upper sensor 450 detects the blocking member 480, the controller stops the rotation of the rotary motor and the winding operation stops.

After the winding of the slack portion 14 is stopped as described above, the image forming operation is executed, and the slack portion 1 is again returned.
When 4 reaches a predetermined length, the winding operation is restarted. Execution and stop of the winding operation are repeated as described above, and the slack portion 14 is wound around the winding shaft 92 with the image surface 18 facing outward. The discharge portion 12 wound around the winding shaft 92 is connected to the winding shaft 9.
The procedure for detaching from the winding device 60 is the same as the procedure described above for the winding device 60.

Referring to FIGS. 11 and 12, a case in which the slack portion is wound with the image surface inside will be described.

FIG. 11 is a side cross-sectional view showing the winding device when winding inside. FIG. 12 is a side cross-sectional view showing a state where the slack portion is being wound.

In this case, the rotating arm 412 is located at the second position. Further, the slack portion 15 is loosened beyond the winding device 400 in a region where the rotating arm 412 is located (a region on the left side of the winding device on the paper surface of FIG. 11). When the slack portion 15 reaches a predetermined length, the rotating arm 41
2 comes into contact with the rotation stopper 120 at the second position and stops. In this state, the light emitted from the light emitting unit 462 is blocked by the blocking member 480. When the lower sensor 460 detects the blocking member 480, the controller controls the rotation motor to rotate the winding shaft 92 (see FIG. 10) in the direction of arrow F. As a result, the slack portion 15 is moved to the image plane 18.
Is wound around the winding shaft 92 with.

The difference between the inner winding and the outer winding in performing and stopping the winding operation is that the rotating shaft 92 rotates in the opposite direction, and the position and posture of the rotating arm 412 are different. The only difference is. Therefore, the description of the process in which the execution and stop of the winding operation are repeated and the slack portion 15 is wound on the winding shaft 92 will be omitted because it is the same as the above-described case of the outer winding.

Note that the blocking member 480 is connected to the rotating arm 412.
Is not limited to the above position. Blocking member 4
If 80 is fixed at another position, the positions of the two detection sensors 450 and 460 (see FIG. 8) are changed accordingly.

[0091]

As described above, according to the winding device of the present invention, since the pressing means presses the slack portion from the non-image surface on which no image is formed, tension always acts on the discharge portion. are doing. Therefore, even when a stiff recording medium is used, the discharge portion does not rise, so that the position of the recording medium during image formation does not change carelessly. As a result, it is possible to prevent the image quality from deteriorating due to the lifting of the discharge portion.

Here, the pressing means comprises a movable unit which changes its position according to the length of the slack part while contacting the slack part, and a detecting means for detecting the length of the slack part based on the position of the movable unit. In the case where the movable unit is provided, the detecting unit detects the movable unit that contacts the slack portion and changes its position according to the length of the slack portion, so that the length of the slack portion is based on the position of the movable unit. Detected indirectly. Therefore, the slack portion may be caused by various factors such as a difference in the material of the recording medium to be used, a change in the thickness of the discharge portion already wound on the winding shaft, and a change in environmental conditions in a place where the winding device is installed. Even if the position is different, there is no erroneous detection because the slack portion is not directly detected, and it is possible to accurately detect that the length of the slack portion has reached a predetermined length. For this reason,
By setting the predetermined length such that the slack portion does not reach the floor or the like, the slack portion can be wound up before the slack portion contacts the floor or the like.

Here, the winding axis is a rotation direction in both a first rotation direction in which the image is formed on the image surface outside and a second rotation direction in which the image is formed on the image surface inside. When the rotation direction of the winding shaft is the first rotation direction, the discharge portion is loosened on one of the two sides sandwiching the winding shaft. On the other hand, when the rotation direction of the winding shaft is the second rotation direction, the discharge portion is slackened on the side opposite to one of the two sides sandwiching the winding shaft. However, since the position of the movable unit changes according to the length of the slack portion, the detecting means accurately detects the movable unit even if the position of the slack portion is different. Therefore, regardless of whether winding with the image surface facing outside or winding with the image surface facing inside is selected,
It can be detected that the length of the slack portion has reached a predetermined length. For this reason, in either case of winding with the image surface outside and winding with the image surface inside, by setting the predetermined length to a length where the slack portion does not reach the floor etc.,
The slack portion can be rolled up before the slack portion comes into contact with the floor or the like.

In the case where the movable unit is provided with a rotating shaft concentric with the winding shaft and changes its position by rotating around the rotating shaft, the rotating shaft of the movable unit may be used. And the winding shaft are concentric, so that the position of the movable unit can be smoothly changed according to the length of the slack portion. Further, by changing the rotation direction of the winding shaft, the slack position of the slack portion is changed from one of the two sides sandwiching the winding shaft to a side opposite to the one side. However, since the movable unit can rotate about the rotation axis concentric with the winding shaft, it can be easily adjusted so that the movable unit comes into contact with the slack portion in accordance with a change in the slack position of the slack portion. Therefore, when winding the slack portion by changing the rotation direction of the winding shaft, preparation can be completed in a very short time.

Further, a movable unit is provided at each of both ends in the longitudinal direction of the take-up shaft and forms a pair. When the length of the slack portion changes because the slack portion comes into contact with the bar-shaped member, the bar-shaped member and the bar-shaped member are connected in accordance with the change. The turning arm connected by the rod-shaped member turns. As described above, the main components of the movable unit are the pair of rotating arms and the rod-shaped members connecting the distal ends of these rotating arms. Therefore, the structure of the movable unit is extremely simple. Further, the operation of the movable unit is only a simple rotation. For this reason, there is almost no trouble in the detection of the movable unit due to the failure or adjustment failure of the movable unit, and the slack portion can be stably wound up.

Furthermore, in the case of a winding device provided with a rotation stopper for restricting the movable unit so that the movable unit rotates within a predetermined range, the movable unit can be smoothly moved according to the length of the slack portion. In addition, the rotation of the movable unit can be limited within a range in which the movable unit surely rotates. As a result, the movable unit reliably rotates in accordance with the length of the slack portion, so that when the detecting means detects the movable unit, it is accurately detected that the length of the slack portion has reached the predetermined length. It is done. Still further, the movable unit has an arc portion extending in an arc shape from the rotation arm in opposite directions along a circle formed around the rotation axis, and the detecting means is provided with a length of the slack portion. When the arc reaches a predetermined length, the arc is detected near the arc. If the arc is located near the arc, the arc is extended as described above. Even if the length of the slack portion exceeds a predetermined length within the time from the detection of the slack portion to the start of winding of the slack portion, the portion of the arc portion first detected by the detecting means. The other parts continue to be detected by the detecting means. Therefore, there is no inconvenience that the slack portion cannot be detected even though the length of the slack portion has reached the predetermined length. The arc portion extends from the rotating arm in opposite directions. For this reason, even if the slack position of the slack portion is changed to either of the two sides sandwiching the winding shaft by changing the rotation direction of the winding shaft, one of the arc portions extending in both opposite directions is removed. The detecting means can detect. Therefore, it is possible to detect that the length of the slack portion has reached a predetermined length regardless of the direction of rotation of the winding shaft.

Further, since the detecting means is arranged near the arc, the distance between the detecting means and the arc is small. Accordingly, it is possible to prevent foreign matter having a size detected by the detecting means from entering between the detecting means and the arc portion.
Therefore, it is possible to prevent the detection means from erroneously detecting a foreign substance,
It is possible to accurately detect that the length of the slack portion has reached a predetermined length.

[Brief description of the drawings]

FIG. 1 is a side sectional view showing a plotter provided with a winding device of the present invention.

FIG. 2 is a side cross-sectional view showing a state where a slack portion of a recording sheet is being wound.

FIG. 3 is an exploded perspective view illustrating a winding unit, a movable unit, and members around the winding unit of the winding device.

FIG. 4A is a front view showing a movable unit and a winding unit shown in FIG. 3; (B) is a front view showing a winding unit.

FIG. 5A is a left side view showing a movable unit and members around the movable unit. (B) is a right side view showing the movable unit and members around it.

FIG. 6 is a side view showing a rotation range of a rotation arm.

FIG. 7 is a side cross-sectional view showing an example of a state in which a slack portion of a recording sheet is wound up with an image surface inside.

FIG. 8 is a side sectional view showing a winding device having different detection means.

FIG. 9 is a side cross-sectional view showing a state where a slack portion is being wound.

FIG. 10 is a plan view showing a winding unit, a movable unit, and a detector of the winding device shown in FIGS. 8 and 9;

FIG. 11 is a side cross-sectional view showing an example of a state in which a slack portion of a recording sheet is wound with an image surface inside.

FIG. 12 is a side cross-sectional view showing a state where a slack portion is being wound.

FIG. 13 is a side sectional view showing a plotter combined with a conventional winding device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Recording paper (recording medium) 12 Ejection part 14, 15 Loose part 18 Image surface 20, 300 Plotter (image forming apparatus) 60, 400 Winding device 70, 80 Rotating arm 72, 74 Arc part 92 Winding shaft 100 Rod shape Member 120 Rotation stopper 130 Arc sensor E First rotation direction F Second rotation direction

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 3F055 AA01 CA22 DA01 FA03 FA05 FA18 3F105 AA02 AB02 BA18 CA06 DA08 DB11 DC11

Claims (7)

[Claims] 1. A winding device for winding a slack slack portion on a rotating winding shaft while slackening a long discharging portion discharged from an image forming apparatus for forming an image on a recording medium. A winding device comprising: a pressing unit that presses the slack portion from the non-image surface on which an image is not formed until the winding portion is wound. 2. A movable unit whose position changes according to the length of the slack portion while being in contact with the slack portion, and detection for detecting the length of the slack portion based on the position of the movable unit. The winding device according to claim 1, further comprising means. 3. The winding shaft is configured to rotate in both a first rotation direction in which an image on which an image is formed is wound outside and a second rotation direction in which an image is formed on an image surface inside. 3. The winding device according to claim 2, wherein the winding device selectively rotates. 4. The apparatus according to claim 1, wherein the movable unit has a rotating shaft concentric with the winding shaft, and changes its position by rotating around the rotating shaft. 4. The winding device according to 2 or 3. 5. A pair of a movable arm, which is disposed at each of both ends in a longitudinal direction of the winding shaft to form a pair, and a rotating arm that rotates about the rotating shaft. The winding device according to claim 4, further comprising a rod-shaped member that connects the distal ends of the rotating arms and that contacts the slack portion. 6. The winding device according to claim 4, further comprising a rotation stopper that limits the movable unit to rotate within a predetermined range. 7. The movable unit has an arc portion extending in an arc shape from the pivot arm in opposite directions along a circle formed around the pivot axis. The said arc part is detected when the length of the said slack part reaches the said predetermined length, It is arrange | positioned in the vicinity of this arc part, The thing characterized by the above-mentioned. Winding device.