JP7205069B2 - Conveying object conveying device, image forming device - Google Patents

Description

The present invention relates to a transported object transporting device and an image forming apparatus having the same.

Conventionally, as an image forming apparatus to which a transported object conveying device is applied, a rolled paper, which is an example of the transported object, is nipped between a transport roller and a pinch roller and transported to a printing unit. The type to print is known.

In one example of an inkjet recording apparatus, the transport roller and the pinch roller are separated from each other, and the front end of the roll paper is manually inserted, and the transport roller and the pinch roller are pressed against each other in a state in which left and right slack in the transport direction of the roll paper is removed. It is desirable to set This is from the viewpoint of preventing skew and wrinkles, and it is necessary to apply tension to the roll paper.

As a well-known technique for applying tension to roll paper, there is a "roll paper support mechanism" that always generates a certain or more back tension relative to the transport force of the roll paper and has a low rate of change in back tension with respect to changes in the remaining amount of roll paper. (Patent Document 1).

In the technique disclosed in Patent Document 1, a torque limiter is fixed to the spool that supports the roll paper, and the idling torque of the torque limiter is used as the rotation resistance of the roll paper in order to generate a certain amount or more of back tension with respect to the conveying force of the roll paper. We are using. As a result, it is possible to stably apply a back tension to the roll paper and prevent the roll paper from slipping.

However, when the rotational load is constantly applied by the torque limiter in this way, it is necessary to make the front end of the roll paper longer and insert it between the conveying roller and the pinch roller when loading the roll paper, or before removing the roll paper. There is a problem that it becomes an obstacle when you want to rewind to .

The present invention has been made to solve such problems, and its technical problem is to easily attach and detach a conveyed object by applying tension only when necessary without adding any new parts. It is to provide a function that can be performed by

In order to solve the above technical problem, one aspect of the present invention relates to a conveyed object conveying device, which conveys a sheet delivered from a rolled conveyed object held by a first rotating shaft. a holding member arranged to face the conveying member and sandwiching the conveying member and the sheet; a motor as a drive source for the first rotary shaft; and a second drive shaft for the motor. a torque limiter provided on a third rotating shaft interposed between the rotating shaft and the first rotating shaft to transmit the rotation of the second rotating shaft to the first rotating shaft; a first encoder sensor attached to the rotating shaft and outputting a first signal capable of detecting the direction and amount of rotation of the first rotating shaft; and the third rotating shaft attached to the third rotating shaft. a second encoder sensor that outputs a second signal capable of detecting the direction and amount of rotation of the shaft; a sensor that detects whether or not the holding member is positioned to hold the sheet; and the first signal. and control means for controlling the rotational drive of the motor according to the second signal and the detection result of the position of the holding member by the sensor, and controlling the state of applying tension to the sheet, the control means is determined based on the first signal and the second signal that the sheet has been delivered and the first rotating shaft is rotating forward, and the nipping member detects that the sheet is detected by the sensor; When it is determined that the second rotating shaft is not in a position to sandwich the when it is determined based on the first signal and the second signal that the sheet is rewound and the first rotating shaft is reversed by controlling the rotational drive of the motor so as to hold the position ; Further, when it is determined by the detection of the sensor that the nipping member is not in a position to nip the sheet, the second rotating shaft rotates in the opposite direction as the sheet is rewound. control of the rotational drive of the motor is stopped so that the rotational shaft of the motor does not become a rotational load.

According to the present invention, with the above configuration, it is possible to easily perform the attachment/detachment work by applying tension to the transported object only when necessary, without requiring the addition of new parts. Problems, configurations, and effects other than those described above will be clarified by the following description of the embodiments.

1 is a schematic configuration diagram showing an ink jet recording apparatus, which is an example of an image forming apparatus to which a transported object conveying apparatus according to an embodiment of the present invention is applied; FIG. FIG. 2 is a schematic configuration diagram when loading roll paper as a transported object into the ink jet recording apparatus shown in FIG. 1 ; 3 is an external perspective view of a main part for explaining a loading error state that can occur when the roll paper shown in FIG. 2 is loaded; FIG. FIG. 2 is a diagram showing the detailed configuration of a paper feed drive unit, which is a main part of the ink jet recording apparatus shown in FIG. 1; 2 is a diagram showing the hardware configuration of a roll paper conveying device, which is a main part of the inkjet recording apparatus shown in FIG. 1; FIG. 6 is a functional block diagram of a control circuit provided in the roll paper transport device shown in FIG. 5; FIG. FIG. 7 is a schematic configuration diagram showing an example of the movement of roll paper in the ink jet recording apparatus when one function of the control circuit shown in FIG. 6 is activated; FIG. 7 is a schematic diagram showing the movement of roll paper in the inkjet recording apparatus when another function of the control circuit shown in FIG. 6 is activated; FIG. 7 is a schematic configuration diagram showing another example of the movement during loading of roll paper in the ink jet recording apparatus when another function of the control circuit shown in FIG. 6 is activated;

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, a conveyed object conveying apparatus of the present invention and an image forming apparatus including the same will be described in detail with reference to the accompanying drawings.

FIG. 1 is a schematic configuration diagram showing an ink jet recording apparatus, which is an example of an image forming apparatus to which a conveying apparatus for conveying objects according to an embodiment of the present invention is applied. Referring to FIG. 1, this ink jet recording apparatus has a configuration in which an object to be conveyed is conveyed from one lower side of a recording apparatus main body 11 to the other lower side via the upper side and wound up. Paper, coated paper, thick paper, OHP, plastic film, prepreg, silver foil, etc. are examples of the transported object, and the roll paper will be described below as an example.

More specifically, the roll paper 2 wound around a rotating shaft is held by the paper feed drive unit 1 on one lower side of the main body 11 of the recording apparatus. The roll paper 2 is drawn upward, passed through the paper feed guide plate 3, and sandwiched between the transport roller 4 and the pinch roller 5. As shown in FIG. A conveying roller 4 is a conveying member that conveys the roll paper 2, and a pinch roller 5 with a depressurizing lever 5a is a nipping member that is arranged to face the conveying roller 4 and pinches the roll paper 2 between itself and the conveying roller 4. is. Thereafter, the roll paper 2 passes through the contact portion (nip) between the transport roller 4 and the pinch roller 5 and the platen portion 7 .

At this time, when the roll paper 2 reaches the platen section 7, the carriage 6 arranged on the platen section 7 scans the print head to form an image. A general example of a print head can be a case in which ink is discharged and dropped. The roll paper 2 on which the image has been formed then passes through a paper ejection guide plate 8 and is taken up by a paper tube 10 held by a paper ejection driving section 9 on the other lower side of the main body 11 of the recording apparatus.

By the way, if the transported object is regarded as an object to be coated with the liquid other than the roll paper 2, various forms can be applied. An object to which a liquid can adhere means an object to which a liquid can adhere at least temporarily, such as an object to which the liquid adheres and adheres, an object to which the liquid adheres and penetrates, and the like. Unless otherwise specified, all materials to which liquid can adhere and be formed into a roll are included. In addition, it is a premise that the liquid needs to be charged and received by ions in the liquid when a voltage is applied. There is no particular limitation as long as it has a viscosity and surface tension that can be applied to the above materials, but it is preferable to have a viscosity of 30 mPa·s or less at room temperature and pressure or by heating or cooling.

Specific examples of liquids include solvents such as water and organic solvents, colorants such as dyes and pigments, functional-imparting materials such as polymerizable compounds, resins, and surfactants, and biocompatible materials such as DNA, amino acids, proteins, and calcium. , solutions, suspensions, emulsions and the like containing edible materials such as natural pigments. Common examples of ink include water-based ink, UV ink, non-VOC ink, vegetable oil ink, soybean oil ink, glycol ink, non-toluene ink, printing ink such as EB ink, pigment ink, dye ink, indelible ink, metal ink, invisible ink, fluorescent ink, and the like. In addition, it is also possible to apply recently developed low-odor inkjet inks, UV-curing precoat liquids, and the like. These can be used, for example, as inkjet inks, surface treatment liquids, constituent elements of electronic elements and light-emitting elements, liquids for forming electronic circuit resist patterns, material liquids for three-dimensional modeling, and the like.

FIG. 2 is a schematic configuration diagram when the roll paper 2 is loaded (set) in the ink jet recording apparatus described above. In FIG. 2, the carriage 6 is schematically illustrated. Referring to FIG. 2, when the roll paper 2 is loaded, an operation is performed to pull up the depressurization lever 5a of the pinch roller 5 with respect to the conveying roller 4 so that the pinch roller 5 is separated. In this state, the leading edge of the roll paper 2 is manually pulled out, and the leading edge of the roll paper 2 is fed along the paper feed guide plate 3 at the position of the arrow A. Further, after the leading edge of the roll paper 2 is passed between the transport roller 4 and the pinch roller 5, the transport roller 4 and the pinch roller 5 are brought into pressure contact so as to sandwich the vicinity of the leading edge of the roll paper 2. FIG. In this state, the vicinity of the leading edge of the roll paper 2 is pressed against the contact portion between the conveying roller 4 and the pinch roller 5 . While the leading edge of the roll paper 2 is pulled out, the roll paper 2 rotates along with it.

FIG. 3 is an external perspective view of a main part for explaining a loading error state that can occur when the roll paper 2 is loaded. Referring to FIG. 3, if the left and right sides of the roll paper 2 are not loaded without slack when the roll paper 2 is loaded as described with reference to FIG. In order to deal with this, it is necessary to apply a certain amount of tension to the left inter-member portion 2L and the right inter-member portion 2R of the roll paper 2 . The state of FIG. 3 shows a loading error state, in which there is no slack in the left part 2L between members of the roll paper 2, but slack is generated in the right part 2R between members. The reason for this is that the roll paper 2 was rotated during the drawing, and sufficient tension could not be applied to the right inter-member portion 2R.

In order to deal with such problems, a technique can be adopted in which a torque limiter is arranged in the paper feeding drive unit 1 that holds the roll paper 2 so that the roll paper 2 is always given tension (rotational load) by a constant torque. However, in this case, when the tip of the roll paper 2 is to be inserted between the conveying roller 4 and the pinch roller 5 when the roll paper 2 is loaded, or when the roll paper 2 is to be rewound before being removed, the roll paper The tension of the paper 2 becomes an obstacle. Therefore, in the present embodiment, it is an object of the present invention to provide a function of applying tension to the roll paper 2 only when necessary, without requiring the addition of new parts.

FIG. 4 is a diagram showing the detailed configuration of the paper feed driving section 1, which is a main part of the above-described ink jet recording apparatus. Referring to FIG. 4, the paper feed drive unit 1 is basically provided with a motor 20 as a drive means for rotating the rotary shaft 2a of the roll paper 2. As shown in FIG. A torque limiter 21 is attached to the center shaft of the motor 20 via a flange 27 attached to the drive shaft. An encoder 25 for detecting the direction and amount of rotation of the flange 27 and an encoder sensor 26 are arranged on the central axis of the flange 27 . An encoder 22 for detecting the direction and amount of rotation of the rotary shaft 2a of the roll paper 2, which serves also as the central shaft of the gear 28 which receives the torque action from the torque limiter 21, and an encoder sensor 23 at a position close to the rotary shaft 2a. are placed. Further, a flange 24 is arranged on the rotating shaft 2a of the roll paper 2, and the roll paper 2 is held by the flange 24. As shown in FIG. In the paper feed drive unit 1, the rotational driving force of the drive shaft of the motor 20 is transmitted to the gear 28 of the rotation shaft 2a of the roll paper 2 via the torque limiter 21 of the center shaft of the flange 27. It is a drive transmission mechanism.

Incidentally, the detection signal from the encoder sensor 26 is called an A-phase signal, and the detection signal from the encoder sensor 23 is called a B-phase signal. Direction and amount of rotation can be detected. Therefore, the encoder sensors 23 and 26 work together with the encoders 22 and 25 to function as detection means (rotary encoders) that output signals capable of detecting the direction and amount of rotation of the roll paper 2 . Further, since the rotational driving force generated by the rotation of the drive shaft of the motor 20 is transmitted to the gear 28 of the rotating shaft 2a of the roll paper 2 via the torque limiter 21, the roll paper 2 is tensioned according to the torque of the torque limiter 21. (back tension) can be applied. However, the function of applying tension to the roll paper 2 only when necessary is not constructed only with such a configuration of the paper feed drive unit 1 .

FIG. 5 is a diagram showing the hardware configuration of a roll paper conveying device, which is a main part of the ink jet recording apparatus described above. The roll paper conveying apparatus according to the present embodiment is provided with a depressurization lever position sensor 29 as detecting means for detecting whether or not the conveying roller 4 and the pinch roller 5 are present at the pinching position of the roll paper 2. Basic. Therefore, the control circuit 30 as a control means controls the motor 20 according to the A-phase and B-phase signals detected by the encoder sensors 23 and 26 indicating the direction and amount of rotation of the roll paper 2 to rotate the roll paper 2. Apply tension. At this time, the sensor signal of the detection result by the pressure release lever position sensor 29 is also taken into consideration.

The control circuit 30 provides a drive signal to the motor 20 to drive and control the motor 20 so that the tension applied to the roll paper 2 can be adjusted, including release. The tension applied to the roll paper 2 is controlled by the control circuit 30 to hold the position of the motor 20 at the positions of the encoders 22 and 25 based on the detection results of the encoder sensors 23 and 26 that detect the positions of the encoders 22 and 25. is adjusted by As a result, the torque (rotational load) of the torque limiter 21 is applied to the roll paper 2 as tension.

As a result of drive control of the motor 20 by the control circuit 30, the tension is freely applied to the roll paper 2, or the suspension of the tension is switched. Specifically, the control circuit 30 manually rotates the roll paper 2 in the pull-out direction by separating the transport roller 4 and the pinch roller 5 when the detection result of the depressurization lever position sensor 29 is not in the nipping position. When it is determined that the material should be loaded, the motor 20 is driven and controlled to suppress the tension. When the control circuit 30 determines that the roll paper 2 should be manually rotated in the direction opposite to the pull-out direction based on the same detection result, the control circuit 30 drives and controls the motor 20 to release the tension.

Furthermore, when it is determined that the roll paper 2 should be manually rotated long in the pull-out direction based on the same detection results and the detection results of the encoder sensors 23 and 26, the control circuit 30 sets the tension to a state in which the tension is suppressed, and then the motor 20 is rotated. is driven and controlled to rotate the roll paper 2 by a predetermined amount in the direction opposite to the pull-out direction, thereby releasing the tension. After that, the state of releasing the tension is used as a trigger to switch the application of the state of suppressing the tension between OFF and ON. In any case, the control circuit 30 holds and controls the motor 20 to apply tension to the roll paper 2 as a rotational load for sliding and rotating action. As a result, it is possible to prevent the roll paper 2 from returning due to the torque of the torque limiter 21 for applying back tension to the roll paper 2 when printing is conveyed.

Incidentally, the components of the paper feed drive unit 1 including the transport roller 4 and the pinch roller 5 in the ink jet recording apparatus, the motor 20 for rotationally driving the rotary shaft 2a of the roll paper 2, the depressurization lever position sensor 29 and the control circuit. 30 constitutes the basic configuration of the roll paper transport device.

FIG. 6 is a functional block diagram of the control circuit 30 provided in the roll paper transport device described above. Referring to FIG. 6, the control circuit 30 functionally includes a pressure release lever position determination unit 31 that determines the detection result of the pressure release lever position sensor 29, and a rotation direction/direction sensor that determines the detection results of the encoder sensors 23 and 26. and a rotation amount determination unit 32 . The control circuit 30 also has a motor control section 33 for controlling the motor 20 . Furthermore, the control circuit 30 includes a time management unit 34 that manages the time required to adjust the tension by judging the detection result of the pressure release lever position sensor 29 and the detection results of the encoder sensors 23 and 26, and the tension control unit 34 based on these judgments. and a number-of-times management unit 35 for managing the number of times of suppression and cancellation of . The control function of the control circuit 30 when the roll paper 2 is attached to and detached from the ink jet recording apparatus will be described below together with the movement of the roll paper 2 .

FIG. 7 is a schematic configuration diagram showing an example of movement when the roll paper 2 is loaded in the ink jet recording apparatus when one function of the control circuit 30 is activated. The carriage 6 is also schematically shown here. Referring to FIG. 7, it is assumed that the conveying roller 4 and the pinch roller 5 are separated from each other as in the case described with reference to FIG. In this state, the pressure release lever position sensor 29 notifies the control circuit 30 of the detection result that the roll paper 2 is not in the nipping position between the transport roller 4 and the pinch roller 5 . In the control circuit 30, the depressurization lever position determination section 31 determines the detection result to that effect.

As shown in FIG. 7, when the roll paper 2 is rotated (normally) in the drawing direction (filling direction), the encoders 22 and 25 of the paper feed driving unit 1 rotate, and the encoder sensors 23 and 26 detect the rotation. The encoder sensors 23 and 26 notify the control circuit 30 of the detection results. In the control circuit 30 , the rotation direction/rotation amount determination unit 32 determines the detection result of the rotation direction and rotation amount of the roll paper 2 . In response to this, the motor control section 33 of the control circuit 30 holds the motor 20 . As a result, the tension T is applied to the roll paper 2, but the tension T is applied to the roll paper 2 in a suppressed manner. In this manner, the roll paper 2 can be loaded with a suppressed tension T applied. The operation of loading the roll paper 2 is as described with reference to FIG. Since the tension T is applied to the roll paper 2 at this time, the loading operation can be easily performed.

The tension applied to the roll paper 2 may be applied by a torque limiter 21 such as a rotary sliding member, or simply by weakly holding the motor 20 (holding the motor 20 at a new position after being moved). Also, from the viewpoint of chattering, it is desirable that the amount of rotation is equal to or greater than a predetermined amount of rotation. Furthermore, there may be a case where the loading operation is not performed immediately after the tension T is applied, and if the motor 20 is always held and controlled, power is consumed. For this reason, it is desirable that the time management unit 34 counts the time and that the motor control unit 33 stops the motor 20 when a timeout occurs after a predetermined time has elapsed.

FIG. 8 is a schematic diagram showing the movement of the roll paper 2 in the ink jet recording apparatus when other functions of the control circuit 30 are activated. The carriage 6 is also schematically shown here. Referring to FIG. 8, it is also assumed here that the conveying roller 4 and the pinch roller 5 are separated from each other. In this state, the pressure release lever position sensor 29 notifies the control circuit 30 of the detection result that the roll paper 2 is not in the nipping position between the transport roller 4 and the pinch roller 5 . In the control circuit 30, the depressurization lever position determination section 31 determines the detection result to that effect.

As shown in FIG. 8, when the roll paper 2 is rotated (reversed) in the reverse direction opposite to the drawing direction (filling direction), the encoders 22 and 25 of the paper feed driving section 1 rotate, and the rotation is detected by the encoder sensor. 23 and 26 detect, and the detection results are notified from the encoder sensors 23 and 26 to the control circuit 30 . In the control circuit 30 , the rotation direction/rotation amount determination unit 32 determines the detection result of the rotation direction and rotation amount of the roll paper 2 . In such a case, it is decided to remove the roll paper 2 . Therefore, when the motor control unit 33 of the control circuit 30 determines that the roll paper 2 is rotating in the reverse direction, it stops the motor 20 to release the tension. Manual winding for removing the roll paper 2 does not require application of tension to the roll paper 2. Therefore, if tension is not applied, the roll paper 2 can be easily rewound when the roll paper 2 is removed.

FIG. 9 is a schematic configuration diagram showing another example of the movement when the roll paper 2 is loaded in the ink jet recording apparatus when another function of the control circuit 30 is activated. The carriage 6 is also schematically shown here. Referring to FIG. 9, it is also assumed here that the conveying roller 4 and the pinch roller 5 are separated from each other. In this state, the pressure release lever position sensor 29 notifies the control circuit 30 of the detection result that the roll paper 2 is not in the nipping position between the transport roller 4 and the pinch roller 5 . In the control circuit 30, the depressurization lever position determination section 31 determines the detection result to that effect.

As shown in FIG. 9, if the roll paper 2 is rotated (normally) in the drawing direction (filling direction) for a long time, the loading operation will be hindered if the tension T is always applied to the roll paper 2 . Therefore, when a certain degree of rotation of the roll paper 2 in the pull-out direction is detected, the tension T is temporarily suppressed and then the roll paper 2 is rotated in the direction opposite to the pull-out direction by a predetermined amount to release the tension T. . After that, the state in which the tension T is released is used as a trigger, and the application of the state in which the tension T is suppressed is switched between OFF and ON. That is, in such a case, the tension T is suppressed, the tension T is released by the reverse rotation of the roll paper 2, the suppression of the tension T is turned off, the tension T is released by the reverse rotation of the roll paper 2, and the tension T is suppressed. is turned on.

When executing such a control procedure as well, the encoders 22 and 25 of the paper feed drive unit 1 detect the initial rotation of the roll paper 2 in the pull-out direction to some extent, and the results are output from the encoder sensors 23 and 26. The control circuit 30 is notified. In the control circuit 30 , the rotation direction/rotation amount determination unit 32 determines the detection result of the rotation direction and rotation amount of the roll paper 2 . Therefore, the motor control section 33 of the control circuit 30 holds the motor 20 . As a result, the tension T to be applied to the roll paper 2 is started and applied so as to be restrained. After that, the motor control unit 33 rotates the motor 20 in the reverse direction so that the roll paper 2 is pulled out by a predetermined amount in the opposite direction (Fig. 9) to release the tension T.

Since the rotation direction/amount determination unit 32 continues to determine the detection result of the rotation direction and rotation amount of the roll paper 2 , the motor control unit 33 subsequently stops the motor 20 and the roll paper 2 is rotated. Turn off the restraint application of the tension T. Furthermore, the motor control unit 33 reversely rotates the motor 20 to rotate the roll paper 2 by a predetermined amount in a direction opposite to the pull-out direction, thereby releasing the tension T. FIG. Since the rotation direction/amount determination unit 32 continues to determine the detection result of the rotation direction and rotation amount of the roll paper 2 even after this, when the rotation of the roll paper 2 in the pull-out direction is detected, The motor control unit 33 holds and controls the motor 20 to suppress and apply the tension T to the roll paper 2 . When the roll paper 2 is rotated in the reverse direction, the application of the tension T is unnecessary, so the application of the suppression of the tension T is always kept off. In this way, when it is determined that the roll paper 2 should be rotated long in the pull-out direction, the suppression of the tension T to the roll paper 2 is turned on and off to switch between the suppression of the tension T and the release thereof. As a result, even when the roll paper 2 is set while being rotated in the pull-out direction, the suppressed tension T is intermittently and appropriately applied to the roll paper 2, and the loading operation can be performed smoothly and easily.

Incidentally, since the number of times that the suppression of the tension T is turned off and on is managed by the number-of-times management unit 35, the motor control unit 33 can easily control the driving of the motor 20. FIG. In this case as well, it is conceivable that the tension T is applied to the roll paper 2 once and then the roll paper 2 is rotated in the opposite direction to release the tension T, and then the loading operation is not performed immediately. Therefore, it is desirable that the time management unit 34 counts time here as well, and that the motor control unit 33 stops the motor 20 when a timeout occurs after a predetermined time has elapsed.

As described above, according to the roll paper transport apparatus according to the embodiment, when the roll paper 2 is manually loaded into the ink jet recording apparatus with the transport roller 4 and the pinch roller 5 separated, the drawer length The tension T can be suppressed and applied to the roll paper 2 when necessary according to the conditions. This makes loading easier. On the same premise, when the roll paper 2 is manually removed from the ink jet recording apparatus, the unnecessary tension T is released. This makes the removal work easier. As a result, it is possible to easily attach and detach the roll paper 2 by applying tension to the roll paper 2 only when necessary without adding new parts.

The present invention is not limited to the above-described embodiments, and various modifications are possible without departing from the technical scope of the invention. subject of the present invention. Although the above embodiment shows a preferred example, those skilled in the art can realize various modifications from the disclosed contents, which are described in the appended claims. included in the defined technical scope.

REFERENCE SIGNS LIST 1 paper supply drive unit 2 roll paper 2a rotary shaft 3 paper supply guide plate 4 conveying roller 5 pinch roller 5a depressurization lever 6 carriage 7 platen unit 8 paper discharge guide plate 9 paper discharge drive unit 10 paper tube 11 main body of recording apparatus 20 motor 21 torque limiter 22, 25 encoder 23, 26 encoder sensor 24, 27 flange 28 gear 29 pressure release lever 30 control unit 31 pressure release lever position determination unit 32 rotation direction and rotation amount determination unit 33 motor control unit 34 time management unit 35 number of times Management Department

JP-A-6-219002

Claims (2)

a conveying member that conveys a sheet fed from a roll-shaped conveyed object held by the first rotating shaft;
a sandwiching member arranged to face the conveying member and sandwiching the conveying member and the sheet;
a motor as a drive source for the first rotating shaft;
provided on a third rotating shaft interposed between a second rotating shaft as a drive shaft of the motor and the first rotating shaft, and rotating the second rotating shaft to the first rotating shaft; a torque limiter to transmit;
a first encoder sensor attached to the first rotating shaft and outputting a first signal capable of detecting the direction and amount of rotation of the first rotating shaft;
a second encoder sensor attached to the third rotating shaft and outputting a second signal capable of detecting the direction and amount of rotation of the third rotating shaft;
a sensor for detecting whether or not the holding member is positioned to hold the sheet;
a control means for controlling the rotational drive of the motor according to the first signal, the second signal, and the detection result of the position of the nipping member by the sensor, and controlling the state of applying tension to the sheet;
with
The control means is
When it is determined based on the first signal and the second signal that the sheet has been delivered and the first rotating shaft is rotating forward, and the nipping member nips the sheet based on the detection of the sensor. position of the second rotating shaft so that the second rotating shaft acts as a rotational load against the first rotating shaft rotated by feeding the sheet when it is determined that the second rotating shaft is not in the position to controlling the rotational drive of the motor to hold ;
When it is determined based on the first signal and the second signal that the sheet is rewound and the first rotating shaft is reversed, and the nipping member nips the sheet by detection of the sensor. When it is determined that the second rotating shaft is not in the position where the sheet is rewound, the motor is rotated so that the second rotating shaft does not become a rotational load with respect to the first rotating shaft that reverses as the sheet is rewound. to stop controlling the
A device for transporting an object to be transported, characterized in that: An image forming apparatus comprising the transported object transporting device according to claim 1 .

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