JP2010113192A - Rotational drive transmission unit and image forming apparatus provided with the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress cost increase and to obtain good rotational control with respect to a rotational drive transmission unit which surely transmits driving force from a motor to a photoreceptor and allows a photoreceptor to be easily separated from the motor. <P>SOLUTION: The rotational drive transmission unit includes: a magnetic aggregation plate 100A on driving shaft side, fixed on an end surface of a driving shaft 110; a magnetic aggregation plate on photoreceptor side 100B, fixed on an end surface of a photoreceptor 11 so as to face the magnetic aggregation plate 100A; a magnetic sensor 150 on photoreceptor side, for detecting magnetism generated by the magnetic aggregation plate 100B on photoreceptor side; and a control section for calculating the rotational speed on the photoreceptor side based on the magnetism detected by the magnetic sensor 150 on photoreceptor side and controlling the motor so that the rotational speed on the photoreceptor side becomes the target speed. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a rotational drive transmission device capable of reliably transmitting a driving force from a power source to a rotating body and easily separating the rotating body from the power source. The present invention also relates to an image forming apparatus.

  In an image forming apparatus such as a copying machine, a printer, a facsimile machine, or a combination machine combining two or more of them, which normally forms a toner image, an electrostatic latent image is usually formed on an image carrier such as a photosensitive member in an exposure process. Then, the electrostatic latent image is developed by a development process to form a visible toner image, and the visible toner image is transferred to a recording medium such as a recording paper by a transfer process, or is temporarily transferred by an intermediate transfer belt or the like. The toner image transferred to the recording medium in the fixing process is fixed onto the recording medium (hereinafter referred to as recording paper). it can.

  In the development process, for example, a drum-type photosensitive member that is an electrostatic latent image carrier and a developing roller that is a developer carrier are carried at a certain interval, and between the developing roller and the drum-type photosensitive member. Development may be performed in which an electric field is formed, and toner as a developer on the developing roller is made to fly to an electrostatic latent image on a drum type photoreceptor to be visualized to form a toner image on a recording sheet. .

  Such an image forming apparatus includes a motor as a power source for rotationally driving the drum-type photosensitive member. On the other hand, the drum type photoreceptor must be able to be pulled out from the main body of the image forming apparatus for maintenance such as jam processing. In this case, since the motor is heavy and a cable for driving and control is attached to the motor, the motor should remain on the main body side of the image forming apparatus. Therefore, a drive transmission device that can transmit and detach the drive is inevitably required between the motor and the drum-type photosensitive member.

  In such a case, it is extremely difficult to make the backlash-free with a coupling that mechanically transmits drive, and it is practically difficult to make the rotation unevenness zero. In particular, in the case of a digital image forming apparatus or a full-color image forming apparatus, the influence of rotation unevenness appears to be a big problem. Japanese Patent Application Laid-Open No. 2000-27885 (Patent Document 1) and Japanese Patent Application Laid-Open No. 2005-208151 (Patent Document 2) disclose techniques regarding such drive transmission and rotation control of a drum type photoconductor.

  The image forming apparatus disclosed in Patent Document 1 is a drive transmission device that transmits a driving force from a power source to an image bearing rotator using a magnetic coupler and can pull out the image bearing rotator from the power source. A magnetic apparatus having a first suction member provided on the power source side and a second suction member provided on the image bearing rotator side and magnetically attracting each other with the first suction member. The suction force F in the suction state between the first suction member and the second suction member is equal to or less than a force that can be easily peeled off by a human, and the first suction member and the second suction member A drive transmission device in which the product of the radius R of the suction portion and the suction force F is equal to or greater than the torque T required to drive the image bearing rotator, and forms a toner image on the image bearing rotator. The toner image is transferred to a recording material to form an image.

  According to this image forming apparatus, it is possible to provide a drive transmission device that is hard to slip and reliably transmits a drive, and that can easily pull out an image bearing rotating body from a power source. As a result, both smooth rotation of the image bearing rotating body and maintainability in the image forming apparatus are achieved.

  An image forming apparatus disclosed in Patent Document 2 includes a rotating body that is a cylindrical photosensitive body on which an electrostatic latent image that is rotatably supported is formed, a rotation driving unit that rotationally drives the rotating body, A magnetic body provided over the entire circumference of the body and magnetized at a predetermined interval, a magnetoresistive element that is fixed in position and detects a magnetic field generated from the magnetic body on the rotating body, and the magnetoresistive element A rotary body drive device including a drive control means for driving and controlling the rotary drive means based on rotation information of the rotary body detected by the image forming apparatus, and an image forming process member disposed around the photoconductor in the rotary drive device. Prepare.

  According to this image forming apparatus, by detecting the magnetic field generated from the magnetic body magnetized at a predetermined interval provided over the entire circumference of the rotating body itself to be rotationally driven by the fixed position magnetoresistive element. When the rotating body rotates, the resistance value of the magnetoresistive element changes for each magnetized region of the magnetic body so that the rotation information of the rotating body can be accurately detected without being affected by eccentricity, etc. Appropriate rotation control of the body is possible.

JP 2000-27885 A Japanese Patent Laid-Open No. 2005-208151

  In the drive transmission device disclosed in Patent Document 1, since the power source and the image carrying rotator are connected via the magnetic coupler, the drive transmission is reliable and the image carrying rotator is removed from the power source. It can be easily pulled out. Therefore, it can be said that it is suitable for an image forming apparatus. However, the specific rotation control is not mentioned.

  In the image forming apparatus disclosed in Patent Document 2, the photosensitive member and the power source are merely coupled via a gear, and the image bearing rotating body cannot be easily pulled out from the power source. Further, in the image forming apparatus disclosed in Patent Document 2, a magnetic body for detecting rotation information is provided over the entire circumference in a non-image area (specifically, near one end portion) of the surface of the photoreceptor. Yes. For this reason, there is a concern about control failure and cost increase due to eccentricity of the rotating body (eccentricity based on imbalance of the magnetic body attached over the entire circumference) by providing such a magnetic body on the rotating body. The Further, a magnetoresistive element is brought into contact with the magnetic body and is slid on the magnetic body. For this reason, control failure and cost due to eccentricity of the rotating body (eccentricity caused by the force received by the rotating body from the magnetoresistive element in contact with the magnetic body) by providing a contact object on the magnetic body provided on the rotating body There is concern about up.

  Therefore, the present invention is a rotational drive transmission device that can transmit a rotational driving force from a power source to a rotating body using magnetic force and can separate the rotating body from the power source, and is good for suppressing an increase in cost. An object of the present invention is to provide a rotation drive transmission device capable of performing a proper rotation control.

  The present invention also relates to an image forming apparatus capable of forming an electrostatic latent image on an electrostatic latent image carrier and developing the electrostatic latent image to form a toner image, which transmits a rotational driving force using magnetic force. In addition, the rotation body can be separated from the power source, and the rotation from the power source included in the image forming apparatus to the rotation body can be rotated by using a rotation drive transmission device capable of controlling the rotation while suppressing an increase in cost. A second problem is to provide an image forming apparatus that transmits a driving force.

In order to solve the first problem described above, the present invention provides the following rotary drive transmission device.
A rotational drive transmission device capable of transmitting a rotational driving force from a power source to a rotating body using magnetic force, and capable of separating the rotating body from the power source,
The rotational drive transmission device
A first magnetic member provided on the power source side;
A second magnetic member provided on the rotating body side and magnetically attracting to the first magnetic member;
A detector that detects at least one of magnetism generated by the first magnetic member, magnetism generated by the second magnetic member, and magnetism formed between the first magnetic member and the second magnetic member;
And a controller that controls the power source based on the magnetism detected by the detector.

  According to this rotational drive transmission device, the rotational driving force can be reliably transmitted from the power source to the rotating body by the magnetic force using the first magnetic member and the second magnetic member, and the rotating body can be easily separated from the power source. it can. It is only necessary to provide a detection unit that detects at least one of the magnetism generated by the first magnetic member, the magnetism generated by the second magnetic member, and the magnetism formed between the first magnetic member and the second magnetic member. Since it is good, the cost increase can be suppressed. In this case, since the member which detects the information about rotation is not provided in a 1st magnetic member and a 2nd magnetic member, eccentricity of a rotary body does not generate | occur | produce but the control failure resulting from this can be suppressed.

The detection unit is configured to detect magnetism generated by the second magnetic member,
The control unit calculates the rotational speed on the rotating body side based on the magnetism generated by the second magnetic member detected by the detecting section, and controls the power source so that the rotational speed on the rotating body side becomes the target speed. Can be configured.

  The control unit calculates the rotation speed on the rotating body side based on the temporal change in the direction of magnetism generated by the second magnetic member on the rotating body side (the direction of the magnetic force lines from the N pole to the S pole). The control unit controls the power source so that the calculated rotation speed on the rotating body side becomes the target speed. For this reason, it is possible to perform feedback control and the like so that the rotational speed on the rotating body side converges to the target speed with a simple configuration (no need to newly provide a member on the first magnetic member and the second magnetic member) Rotation control can be realized.

Further, the detection unit is configured to detect magnetism generated by the first magnetic member,
The control unit calculates the rotational speed on the power source side based on the magnetism generated by the first magnetic member detected by the detection unit, the rotational speed on the power source side is the target speed, and the rotational speed on the rotating body side is the target speed. It can be configured to control the power source to be either of the following.

  The control unit calculates the rotational speed on the power source side based on a temporal change in the direction of magnetism generated by the first magnetic member on the power source side (direction of the magnetic force lines from the N pole to the S pole). The control unit controls the power source so that the calculated rotational speed on the power source side becomes the target speed, or predefines the relationship between the rotational speed on the power source side and the rotational speed on the rotating body side. The rotational speed on the power source side is controlled so that the rotational speed on the rotating body side becomes the target speed (obtained by experiment etc.). For this reason, with a simple configuration, it is possible to perform feedback control or the like so that the rotational speed on the drive source side or the rotating body side converges to the target speed, and good rotational control can be realized.

Further, the detection unit is configured to detect magnetism formed between the first magnetic member and the second magnetic member,
The control unit calculates the angle of the lines of magnetic force formed between the first magnetic member and the second magnetic member based on the magnetism detected by the detection unit, and the detected angle is the target speed of the rotating body. The power source can be controlled so as to have an angle at the time of rotation.

  The control unit calculates the angle of the magnetic lines of force formed between the first magnetic member and the second magnetic member. Although the rotational speed itself cannot be obtained using the angle of the lines of magnetic force, the relative speed difference between the rotational speed on the rotating body side and the rotational speed on the power source side can be calculated. The power source is controlled so that the angle of the magnetic lines of force when the rotation speed on the rotating body side is the target speed (the speed difference at this time is constant and the angle of the magnetic lines of force is also constant). For this reason, it is possible to perform feedback control or the like so that the rotational speed on the rotating body side converges to the target speed with a simple configuration, and good rotational control can be realized.

The detection unit is configured to detect magnetism generated by the first magnetic member and magnetism generated by the second magnetic member,
The control unit calculates the rotation speed on the rotating body side based on the magnetism generated by the second magnetic member detected by the detection section, and detects the rotation speed on the rotating body side to be the target speed and is detected by the detection section. The rotational speed on the power source side is calculated based on the magnetism generated by the first magnetic member, so that the difference between the rotational speed on the rotating body side and the rotational speed on the power source side becomes a predetermined value. It can be configured to control the power source.

  The control unit calculates a rotation speed on the rotating body side based on a temporal change in the direction of magnetism generated by the second magnetic member on the rotating body side so that the calculated rotation speed on the rotating body side becomes the target speed. Control the power source. Further, the control unit calculates a rotation speed on the drive source side based on a temporal change in the direction of magnetism generated by the first magnetic member on the rotation body side, and calculates the rotation speed on the drive source side and the rotation body side. The power source is controlled so that the difference from the rotational speed of the motor becomes a predetermined value (a constant value including 0). In this way, the rotation control for converging the rotation speed of the rotating body to the target speed and the rotation control for setting the difference between the rotation speed of the rotating body and the rotation speed of the power source to a constant value are performed. Stabilize more.

In order to solve the second problem described above, the present invention provides the following image forming apparatus.
An image forming apparatus capable of forming an electrostatic latent image on an electrostatic latent image carrier and developing the electrostatic latent image to form a toner image. A rotational driving force is transmitted from a power source included in the forming apparatus to the rotating body.

  According to this image forming apparatus, since the rotational drive transmission device described above is used, the rotational driving force is reliably transmitted from the power source to the rotating body by the magnetic force using the first magnetic member and the second magnetic member, and from the power source. The rotating body can be easily separated. It is only necessary to provide a detection unit that detects at least one of the magnetism generated by the first magnetic member, the magnetism generated by the second magnetic member, and the magnetism formed between the first magnetic member and the second magnetic member. Since it is good, the cost increase can be suppressed. In this case, since the member which detects the information about rotation is not provided in a 1st magnetic member and a 2nd magnetic member, eccentricity of a rotary body does not generate | occur | produce but the control failure resulting from this can be suppressed. Thereby, it is possible to realize an image forming apparatus using a rotational drive transmission device capable of controlling the rotation while suppressing an increase in cost.

  The rotating body can be configured to be a photoconductor that carries an electrostatic latent image. In this way, the rotational driving force can be transmitted to the photosensitive member using magnetic force, the photosensitive member can be separated from the power source, and the rotation of the photosensitive member can be controlled with high accuracy.

  As described above, according to the present invention, a rotational drive transmission device capable of transmitting rotational driving force from a power source to a rotating body using magnetic force and separating the rotating body from the power source, which increases the cost. Thus, it is possible to provide a rotation drive transmission device that can suppress rotation and perform good rotation control.

  According to the present invention, there is also provided an image forming apparatus capable of forming an electrostatic latent image on an electrostatic latent image carrier and developing the electrostatic latent image to form a toner image. It is possible to separate the rotating body from the power source and transmit the power from the power source provided in the image forming apparatus to the rotating body by using a rotational drive transmission device capable of controlling the rotation while suppressing an increase in cost. An image forming apparatus that transmits rotational driving force can be provided.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description, the same parts are denoted by the same reference numerals. Their names and functions are also the same. Therefore, detailed description thereof will not be repeated. In the following description, an image forming apparatus provided with the rotational drive transmission device according to the embodiment of the present invention (this image forming apparatus is also according to the embodiment of the present invention) will be described.

<First Embodiment>
The image forming apparatus according to the first embodiment of the present invention will be described below. In describing the rotational power transmission device, an image forming apparatus provided with the rotational power transmission device will be described.
[Entire configuration of image forming apparatus]
FIG. 1 is a front view of the image forming apparatus A. FIG. The image forming apparatus A shown in FIG. 1 is a copier provided with an image reading device S, but can be said to be a multi-function machine having both a function of a facsimile machine and a printer function for printing according to image information supplied from a computer or the like. It is. In the following description, the recording medium is described as recording paper.

  The image forming apparatus A in FIG. 1 includes an image forming unit B that performs image formation and a recording paper cassette unit CS having recording paper storage cassettes C1 to C4 below the image forming unit B. The image reading device S is located above the image forming portion B that performs image formation. The image reading apparatus S is equipped with an automatic document feeder ADF and an operation panel PA.

  The automatic document feeder ADF is openable and closable, and also serves as a cover that covers a document placed on a glass plate g1 that is a document placement table of the image reading device S. The operation panel PA is equipped with a liquid crystal display section D in addition to a start key for instructing copy image formation and facsimile transmission, a key group Ke such as a numeric keypad for setting the number of image formations, and the like. The liquid crystal display unit D is used to reflect and display key operations by the user, to display an instruction menu for the user, to display information from the image forming unit B that performs image formation, and the like.

  The image reading device S can optically read an image of a document placed stationary on the platen glass g1, and is transported from the document placing tray a1 by the automatic document feeder ADF, and the document discharge tray a2. It is also possible to optically read an image of a document that is discharged along the way and moves along the glass plate g2 for document panning of the image reading device S.

  The image data read by the image reading device S is sent to an image forming unit B that performs image formation, and is used for image formation there or for facsimile transmission. Image data transmitted from a computer (not shown) or the like is sent to the image forming unit B and used for image formation there.

  The image forming unit B forms a toner image on recording paper by an electrophotographic method. The image forming unit B in the image forming apparatus A according to the present embodiment includes a yellow image forming unit Y, a magenta image forming unit M, a cyan image forming unit C, and a black image forming unit K arranged along the intermediate transfer belt 4. The toner image formed by each image forming unit is primarily transferred to the intermediate transfer belt 4, and the recording paper P supplied from one of the cassettes is a multiple toner image that is primarily transferred and superimposed on the intermediate transfer belt 4. And a fixing device 7 (including a heating roller 71 and a pressure roller 72) to obtain a color image, which is a so-called tandem type full color type. The recording paper P on which the toner image is fixed is discharged to a discharge tray T.

  The image forming unit B can form a monochrome image or can form an image using any two or three image forming units. The image forming apparatus A may be a 4-cycle color type or a monochrome type in the first place.

  As described above, the image forming unit B includes the intermediate transfer belt 4. The intermediate transfer belt 4 is wound around a driving roller 31 and a roller 32 facing the driving roller 31, and the driving roller 31 is belt driving unit. Can be rotated in the counterclockwise direction (arrow direction in the figure).

  A cleaner is in contact with the intermediate transfer belt 4 on the roller 32 and cleans the secondary transfer residual toner and the like on the intermediate transfer belt 4. The secondary transfer roller 5 faces the intermediate transfer belt 4 on the driving roller 31.

  The secondary transfer roller 5 forms a nip portion with the intermediate transfer belt 4 and is rotated by the rotation of the intermediate transfer belt 4 or by the movement of the recording paper P fed to the nip portion. To do. A secondary transfer bias can be applied to the secondary transfer roller 5 from a secondary transfer bias power source.

  A timing roller 6 is disposed below the secondary transfer roller 5, and the recording paper storage cassette group described above is further below the timing roller 6. Above the secondary transfer roller 5, the above-described fixing device 7 is disposed.

  Between the driving roller 31 and the roller 32 around which the intermediate transfer belt 4 is wound, the yellow image forming unit Y and the magenta image forming unit described above from the roller 32 toward the driving roller 31 along the intermediate transfer belt 4. M, cyan image forming unit C, and black image forming unit K are arranged in this order.

  Each of the Y, M, C, and K image forming units includes a drum-type photoconductor 11 around which a charger, an image exposure device, a developing device, a primary transfer roller 2, and a photoconductor. A cleaning device and the like for removing and cleaning the primary transfer residual toner and the like on the body 11 are arranged in this order.

  The primary transfer roller 2 faces the photoconductor 11 with the intermediate transfer belt 4 in between, and rotates as the intermediate transfer belt 4 travels. A primary transfer bias for primary transfer of a toner image formed on the photoreceptor 11 to the intermediate transfer belt 4 can be applied to the primary transfer roller 2 from a primary transfer bias power source.

  The exposure apparatus performs image exposure on the photoconductor 11 using a laser beam in accordance with image information provided from the image reading apparatus S or a personal computer (not shown). The photoconductor 11 in each image forming unit is a negatively chargeable organic photoconductor here, and is rotationally driven by a photoconductor drive motor (not shown). A charging voltage can be applied to the charger in each image forming unit at a predetermined timing from a charging power supply (not shown).

  The developing unit in each image forming unit employs a negatively chargeable toner in the present embodiment, and an electrostatic latent image formed on the photoconductor 11 is developed from a developing bias power source (not shown) to a developing bias voltage. Reversal development can be performed with a developing roller to which is applied.

  As described above, the image forming unit B can form an image using one or more of the Y, M, C, and K image forming units.

  Taking a case where a full color image is formed using all of the image forming portions Y, M, C and K as an example, a yellow toner image is first formed in the yellow image forming portion Y, and this is applied to the intermediate transfer belt 4 by 1. Next transfer. That is, in the yellow image forming portion Y, the photosensitive member 11 is rotationally driven in a predetermined direction, and the surface of the photosensitive member 11 whose surface is uniformly charged to a predetermined potential by a charger is transferred from the image exposure device to the yellow image. The yellow electrostatic latent image is formed on the photoconductor 11. This electrostatic latent image is developed by a developing roller to which a developing bias of a developing unit having yellow toner is applied to become a visible yellow toner image, and this visible yellow toner image is formed on the intermediate transfer belt 4 by the primary transfer roller 2. Primary transfer. At this time, a primary transfer bias voltage is applied to the primary transfer roller 2 from a power supply device (not shown).

  Similarly, a visible magenta toner image is formed in the magenta image forming unit M and transferred to the intermediate transfer belt 4, and a visible cyan toner image is formed and transferred to the intermediate transfer belt 4 in the cyan image forming unit C. A visible black toner image is formed at the forming portion K and transferred to the intermediate transfer belt 4. The visible toner images of yellow, magenta, cyan, and black are formed at the timing when these are transferred onto the intermediate transfer belt 4 in an overlapping manner. The multiple toner images formed on the intermediate transfer belt 4 are moved toward the secondary transfer roller 5 by the rotation of the intermediate transfer belt 4.

  On the other hand, the recording paper P is pulled out from any recording paper storage cassette by a recording paper supply roller (not shown), supplied to the timing roller 6, and is on standby. The recording roller P waiting at the timing roller 6 is supplied to the nip portion between the intermediate transfer belt 4 and the secondary transfer roller 5 in accordance with the multiple toner images sent by the intermediate transfer belt 4. 6 starts to feed the recording paper P, and is fed into the nip portion, and a multiple toner image is secondarily formed on the recording paper P by the secondary transfer roller 5 to which a secondary transfer bias is applied from a power supply (not shown). Transcribed.

  Thereafter, the recording paper P is passed through the fixing device 7, where the multiple toner images are fixed on the recording paper P under heat and pressure and discharged onto the tray T. The secondary transfer residual toner or the like remaining on the intermediate transfer belt 4 is removed and cleaned by a cleaner, and the primary transfer residual toner or the like remaining on the photoconductor 11 in each image forming unit contacts the photoconductor 11 of the cleaning device. It is removed and cleaned by a cleaning blade. An image is formed as described above.

  In the image forming apparatus A having such a structure and operation, the photosensitive member 11, the driving roller 31 of the intermediate transfer belt 4, the developing roller, and the fixing roller (the driving roller of the heating roller 71 and the pressure roller 72) are provided. It is driven to rotate. And these rollers and a drive source are connected via the rotational drive transmission device (magnetic coupling) which concerns on this Embodiment. For this reason, the transmission of the drive is reliable, and the photosensitive unit, the intermediate belt unit, the developing unit, the fixing unit, and the like including the roller serving as the rotating body are easily pulled out (separated) from the image forming apparatus A. ) Is possible. The rollers connected to the drive source by the rotational drive transmission device according to the present embodiment may be other than these rollers. In the following, the rotating body will be described as the photoreceptor 11.

[Structure of rotational drive transmission device]
The rotational drive transmission device of the image forming apparatus A as described above will be described. FIG. 2 is a diagram showing an outline of the configuration of the rotational drive transmission device 100 that transmits rotational force in a non-contact manner from the drive source (motor) to the photoconductor 11 in the image forming apparatus A shown in FIG.

  As shown in FIG. 2, the rotational drive transmission device 100 includes a drive shaft side magnetic assembly plate 100A (hereinafter simply referred to as a magnetic assembly plate 100A) fixed to the end surface of the drive shaft 110, and a magnetic assembly plate 100A. The photosensitive member-side magnetic assembly plate 100B (hereinafter simply referred to as the magnetic assembly plate 100B) fixed to the end face of the photosensitive member 11 so as to face the surface. The magnetic aggregate plate 100A and the magnetic aggregate plate 100B have the same configuration and magnetically attract each other. These magnetic gathering plates have the same number of N-pole fan-shaped magnetic bodies as N-pole fan-shaped magnetic bodies whose fan-shaped tips are N poles and S-pole fan-shaped magnetic bodies whose fan-shaped tips are S poles. And S pole fan type magnetic bodies are alternately coupled.

  3 and 4 show the state of magnetic lines of force in such a rotary drive transmission device 100. FIG. FIG. 3 shows the state of magnetic lines of force when the south pole fan-shaped magnetic body of the magnetic aggregate plate 100B is opposed to the north pole fan-shaped magnetic body of the magnetic aggregate plate 100A and stopped. As shown in FIG. 3, between the magnetic assembly plate 100A and the magnetic assembly plate 100B, the drive shaft 110 and the rotation shaft of the photoconductor 11 from the end face of the N-pole fan-type magnetic body to the end face of the S-pole fan-type magnetic body. Magnetic field lines are generated parallel to In the rotational drive transmission device 100, when the drive shaft 110 rotates, the magnetic aggregate plate 100A fixed to the end surface of the drive shaft 110 rotates. As the magnetic aggregate plate 100A rotates, the magnetic field generated between the magnetic aggregate plate 100A and the magnetic aggregate plate 100B changes as shown in FIG. The magnetic aggregate plate 100B fixed to the end face of the photoconductor 11 is rotated by being pulled by the change of the magnetic field, and the photoconductor 11 is rotated.

  FIG. 4 shows the state of the lines of magnetic force in the magnetic aggregate plate 100A or the magnetic aggregate plate 100B. FIG. 4 shows a state of magnetic lines of force as viewed from the end face of the magnetic aggregate plate 100A or the end face of the magnetic aggregate plate 100B, and next to the same magnetic aggregate plate 100A from the tip of the N pole fan type magnetic body of the magnetic aggregate plate 100A. Magnetic field lines are generated at the tip of the S-pole fan type magnetic body. Such lines of magnetic force are generated 360 degrees around the rotation axis. The same applies to the magnetic aggregate plate 100B.

  As shown in FIG. 4, when the magnetic assembly plate 100B rotates in a state where magnetic lines of force are formed, the direction of the magnetic field lines changes alternately with time at a fixed position in a direction perpendicular to the rotation axis of the magnetic assembly plate 100B. . For example, as shown in FIG. 4, it is possible to detect a change in the direction of the lines of magnetic force detected by the photoconductor side magnetic sensor 150 (hereinafter sometimes simply referred to as the magnetic sensor 150). At this time, the direction of the lines of magnetic force is alternately changed by approximately 180 degrees.

[Control structure of rotary drive transmission device]
FIG. 5 shows a control structure of the rotational drive transmission device 100 of the image forming apparatus A according to the present embodiment. As shown in FIG. 5, a magnetic sensor 150 is provided in the direction perpendicular to the rotation axis of the magnetic aggregate plate 100B so as to face the rotational circumferential surface of the magnetic aggregate plate 100B. The magnetic sensor 150 detects a change in the magnetic field due to rotation of the magnetic body (N-pole fan-type magnetic body and S-pole fan-type magnetic body), and outputs a voltage corresponding to the N pole and the S pole. . More specifically, it is a sensor of a type that outputs a pulse of switching between the N pole and the S pole, and is used for detecting a time interval of switching between the N pole and the S pole. By using this type of magnetic sensor 150, as described above, the direction of magnetic field lines that are alternately switched is detected by the magnetic sensor 150, and rotation is performed based on time information when the direction of the magnetic field lines are alternately switched. The speed of the body (here, the rotational speed and angular speed of the photoconductor 11, but may be the rotational speed and angular speed of the drive shaft 110 as in the second embodiment described later) is calculated. Feedback control is performed so that the speed of the rotating body becomes the target speed. Hereinafter, this rotation control will be described in detail.

  FIG. 6 is a diagram for explaining the function of the magnetic sensor 150 of FIG. If rotation unevenness does not occur in the rotating body (here, the magnetic aggregate plate 100B fixed to the end face of the photoconductor 11) (when ideally rotating), the magnetic sensor 150 shows FIG. The waveform (magnetic change waveform) in which the switching between the N pole and the S pole is output at regular intervals as shown in FIG. The rotational speed can be obtained based on the time interval until switching from one magnetic pole (N pole) to the other magnetic pole (S pole). When rotation irregularity occurs in the rotating body, as shown in FIG. 6B, the time interval until the magnetic sensor 150 switches from one magnetic pole (N pole) to the other magnetic pole (S pole) is one rotation. It changes every period. Even in this case, the rotational speed can be obtained based on the time interval at which the magnetic poles are switched.

  FIG. 7 is a control block diagram of the image forming apparatus A according to the present embodiment. As shown in FIG. 7, the control block of the image forming apparatus A includes a control unit 160 that controls the entire image forming apparatus A and a photoconductor side magnet connected to an input port (not shown) of the control unit 160. It includes a sensor 150 and a driving motor driver 180 connected to an output port (not shown) of the controller 160 for controlling a motor for driving the photosensitive member 11. Further, other signals are input to the control unit 160 via the input port of the control unit 160, and other signals are output from the control unit 160 via the output port of the control unit 160.

  As shown in FIG. 7, the control unit 160 includes a rotation speed calculation unit 162 that calculates the rotation speed of the photoconductor 11, a target speed storage unit 164 that stores the target speed of the photoconductor 11, and the target speed and the actual rotation. A speed deviation calculating unit 166 that calculates a deviation from the speed.

  As described above, the rotation speed calculation unit 162 calculates the rotation speed of the photoconductor 11 from the time when the direction of the lines of magnetic force are alternately switched based on the pulse signal input from the magnetic sensor 150 to the control unit 160. The target speed storage unit 164 stores a target speed of the photoconductor 11 that is a target value for feedback control. The speed deviation calculation unit 166 calculates a deviation between the rotation speed of the photoconductor 11 calculated by the rotation speed calculation unit 162 and the target speed stored in the target speed storage unit 164. The control unit 160 gives a control command to the drive motor driver 180 so that the speed deviation calculated by the speed deviation calculation unit 166 becomes zero. The drive motor driver 180 controls the number of rotations of the motor that drives the photoconductor 11 based on the control command given from the control unit 160. The control unit 160 does not calculate the speed deviation, and gives a control command to the drive motor driver 180 so that the rotation speed of the photoconductor 11 calculated by the rotation speed calculation unit 162 becomes the target speed. It doesn't matter.

[Control operation of rotational drive transmission device]
A control operation of the image processing apparatus A according to the present embodiment having the above structure will be described. In the following, only the part related to the rotation control of the photosensitive member 11 of the rotation drive transmission device 100 of the image forming apparatus A will be described.

  During image formation by the image forming apparatus A, the magnetic aggregate plate 100A on the drive shaft 110 side and the magnetic aggregate plate 100B on the photoconductor 11 side face each other without contact. Between these magnetic aggregate plates, magnetic lines of force from the N pole to the S pole are formed as shown in FIG. When the drive shaft 110 rotates in this state, the magnetic aggregate plate 100A rotates, and the magnetic field generated between the magnetic aggregate plate 100A and the magnetic aggregate plate 100B changes and is pulled by the change in the magnetic field. Thus, the magnetic aggregate plate 100B fixed to the end face of the photoconductor 11 rotates, and the photoconductor 11 rotates. At this time, if the rotation unevenness does not occur, the magnetic sensor 150 can detect the magnetic field change as shown in FIG. 6A. If the rotation unevenness occurs, the magnetic sensor 150 causes the magnetic field change as shown in FIG. It can be detected.

  In the control unit 160, the rotation speed detection unit 162 calculates the rotation speed of the photoconductor 11, and the speed deviation calculation unit 166 stores the rotation speed of the photoconductor 11 and the target speed storage unit 164 of the photoconductor 11. A deviation from the target rotation speed (target speed) is calculated. The controller 160 provides feedback so that the speed deviation becomes zero, that is, the rotational speed of the photoconductor 11 calculated based on the information detected by the magnetic sensor 150 becomes a preset target speed. Control.

  As described above, according to the rotational drive transmission device and the image forming apparatus according to the present embodiment, the driving force from the drive shaft to the photoconductor is reliably transmitted using magnetic force, and the photoconductor is easily transferred from the drive shaft. Can be separated. Further, it is only necessary to provide a magnetic sensor in the vicinity of the magnetic aggregate plate on the photosensitive member side, so that an increase in cost can be suppressed. Since the rotating body itself is not provided with parts other than the mechanism for transmitting the driving force, it is possible to suppress an increase in cost and to achieve good rotation control because no eccentricity of the rotating shaft occurs.

  The position of the magnetic sensor 150 is not limited to the position described above. There is no particular limitation as long as the change in the magnetic field of the magnetic aggregate plate 100B due to the rotation of the magnetic aggregate plate 100B can be detected.

<Second Embodiment>
The image forming apparatus according to the second embodiment of the present invention will be described below. Detailed description of the same configuration as in the first embodiment will not be repeated here. In particular, the image forming apparatus A and the rotational drive transmission device 100 described with reference to FIGS. 1 to 4 and 6 are the same (for this reason, the image forming apparatus A and the rotational drive transmission device 100 are the same in this embodiment as well. To describe). Image forming apparatus A according to the present embodiment performs rotation control different from that of the first embodiment described above in rotation drive transmission device 100. Hereinafter, this point will be described in detail.

[Control structure of rotary drive transmission device]
FIG. 8 shows a control structure of the rotational drive transmission device 100 of the image forming apparatus A according to the present embodiment. As shown in FIG. 8, the drive shaft side magnetic sensor 250 (hereinafter simply referred to as the magnetic sensor 250) is opposed to the rotational circumferential surface of the magnetic aggregate plate 100A in a direction perpendicular to the rotational axis of the magnetic aggregate plate 100A. May be provided). The magnetic sensor 250 is the same sensor as the magnetic sensor 150 and is attached at a different position. As described in the first embodiment, the direction of alternately changing magnetic lines is detected by the magnetic sensor 250, and the speed of the rotating body (here, the direction of the magnetic lines of force is alternately changed). The rotational speed and angular speed of the drive shaft 110 are calculated. Feedback control is performed so that the speed of the rotating body becomes the target speed. Hereinafter, this rotation control will be described in detail.

  FIG. 9 is a control block diagram of the image forming apparatus A according to the present embodiment. As shown in FIG. 9, the control block of the image forming apparatus A includes a control unit 260 that controls the entire image forming apparatus A, and a drive shaft side connected to an input port (not shown) of the control unit 260. It includes a magnetic sensor 250 and a driving motor driver 180 connected to an output port (not shown) of the control unit 260 for controlling a motor for driving the photoconductor 11.

  As shown in FIG. 9, the control unit 260 includes a rotation speed calculation unit 262 that calculates the rotation speed of the drive shaft 110, a target speed storage unit 264 that stores the target speed of the drive shaft 110, and the target speed and the actual rotation. A speed deviation calculating unit 266 that calculates a deviation from the speed.

  As described above, the rotation speed calculation unit 262 calculates the speed of the drive shaft 110 from the time when the direction of the magnetic field lines is alternately switched based on the pulse signal input from the magnetic sensor 250 to the control unit 260. The target speed storage unit 264 stores a target speed of the drive shaft 110 that is a target value for feedback control. The speed deviation calculation unit 266 calculates a deviation between the rotation speed of the drive shaft 110 calculated by the rotation speed calculation unit 262 and the target speed stored in the target speed storage unit 264. The control unit 260 gives a control command to the drive motor driver 180 so that the speed deviation calculated by the speed deviation calculation unit 266 becomes zero. The drive motor driver 180 controls the number of rotations of the motor that drives the photoconductor 11 based on the control command given from the control unit 260. The control unit 260 gives a control command to the drive motor driver 180 so that the rotation speed of the drive shaft 110 calculated by the rotation speed calculation unit 262 becomes the target speed without calculating the speed deviation. It doesn't matter.

[Control operation of rotational drive transmission device]
A control operation of the image processing apparatus A according to the present embodiment having the above structure will be described. In the following, only the part related to the rotation control of the photosensitive member 11 of the rotation drive transmission device 100 of the image forming apparatus A will be described.

  When the drive shaft 110 rotates during image formation by the image forming apparatus A, the magnetic aggregate plate 100A rotates, and the magnetic field generated between the magnetic aggregate plate 100A and the magnetic aggregate plate 100B changes. The magnetic aggregate plate 100B fixed to the end surface of the photoconductor 11 is rotated by being pulled by the change of the magnetic field, and the photoconductor 11 is rotated. At this time, if the rotation unevenness does not occur, the magnetic sensor 250 can detect the magnetic field change as shown in FIG. 6A. If the rotation unevenness occurs, the magnetic sensor 250 changes the magnetic field as shown in FIG. 6B. It can be detected.

  In the control unit 260, the rotation speed detection unit 262 calculates the rotation speed of the drive shaft 110, and the speed deviation calculation unit 266 calculates the rotation speed of the drive shaft 110 and the drive speed of the drive shaft 110 stored in the target speed storage unit 264. A deviation from the target rotation speed (target speed) is calculated. The control unit 260 performs feedback so that the speed deviation becomes 0, that is, the rotational speed of the drive shaft 110 calculated based on the information detected by the magnetic sensor 250 becomes a preset target speed. Control.

  As described above, according to the rotational drive transmission device and the image forming apparatus according to the present embodiment, the driving force from the drive shaft to the photoconductor is reliably transmitted using magnetic force, and the photoconductor is easily transferred from the drive shaft. Can be separated. Furthermore, it is only necessary to provide a magnetic sensor in the vicinity of the magnetic collecting plate on the drive shaft side, so that an increase in cost can be suppressed. Since the rotating body itself is not provided with parts other than the mechanism for transmitting the driving force, it is possible to suppress an increase in cost and to achieve good rotation control because no eccentricity of the rotating shaft occurs.

  The position of the magnetic sensor 250 is not limited to the position described above. There is no particular limitation as long as the change in the magnetic field of the magnetic aggregate plate 100A due to the rotation of the magnetic aggregate plate 100A can be detected.

  Further, the rotation control of the photoconductor 11 may be performed as follows. By measuring the speed response (delay time, steady rotational speed difference, etc.) between the drive shaft 110 and the photoconductor 11 in advance, the relationship between the rotational speed of the photoconductor 11 and the rotational speed of the drive shaft 110 is defined. Based on this relationship, the rotational speed of the drive shaft 110 is controlled so that the rotational speed of the photoconductor 11 becomes the target speed. That is, the rotational speed of the drive shaft 110 such that the rotational speed of the photoconductor 11 becomes the target speed is stored as the target speed of the drive shaft 110, and the drive shaft 110 is controlled to rotate at the rotational speed. . As a result, the photoconductor 11 rotates at the target speed of the photoconductor.

<Third Embodiment>
The image forming apparatus according to the third embodiment of the present invention will be described below. Detailed description of the same configuration as in the first embodiment will not be repeated here. In particular, the image forming apparatus A and the rotational drive transmission device 100 described with reference to FIGS. To describe). The image forming apparatus A according to the present embodiment performs rotation control different from the first embodiment and the second embodiment described above in the rotational drive transmission device 100. Hereinafter, this point will be described in detail.

[Control structure of rotary drive transmission device]
FIG. 10 shows a control structure of the rotational drive transmission device 100 of the image forming apparatus A according to the present embodiment. As shown in FIG. 10, an intermediate magnetic sensor 350 (hereinafter simply referred to as a magnetic sensor 350) is provided between the magnetic aggregate plate 100A and the magnetic aggregate plate 100B. The magnetic sensor 350 detects the inclination (angle) of the lines of magnetic force generated by the rotation of the magnetic aggregate plate 100A and the magnetic aggregate plate 100B, and outputs a voltage corresponding to the angle. More specifically, it is a sensor of a type that outputs the angle of the magnetic lines formed between the N pole and the S pole, and can detect a change in the direction of the magnetic lines with time. It is used to calculate the rotation speed difference. By using this type of magnetic sensor 350, the angle of the magnetic field lines formed between the N and S poles is detected by the magnetic sensor 350 and rotated based on the time change of the magnetic field angle. The body speed difference (here, the rotational speed difference and angular speed difference between the drive shaft 110 and the photoconductor 11) is calculated. Feedback control is performed so that the speed difference of the rotating body becomes zero. Hereinafter, this rotation control will be described in detail.

  FIG. 11 is a diagram for explaining the function of the magnetic sensor 350 of FIG. If rotation unevenness does not occur in the rotating body (here, the magnetic aggregate plate 100A fixed to the end face of the drive shaft 110 and the magnetic aggregate plate 100B fixed to the end face of the photosensitive member 11) (ideally rotates). (If there is no difference between the rotation speed of the drive shaft 110 and the rotation speed of the photosensitive member 11), the magnetic sensor 350 can obtain a waveform with a constant angle of magnetic lines of force as shown in FIG. . Although the rotational speed (rotational angular speed) itself cannot be obtained, the relative speed difference between the photoconductor 11 and the drive shaft 110 can be calculated. If there is no speed difference in rotation between the drive shaft 110 and the photosensitive member 11 (if the speed difference is 0), the angle is always constant as shown in FIG. When rotation unevenness occurs in the rotating body (if there is a difference between the rotation speed of the drive shaft 110 and the rotation speed of the photoconductor 11), the magnetic sensor 350 detects the speed difference as shown in FIG. The fluctuation appears as a fluctuation in the angle of the magnetic lines of force, and the angle of the magnetic lines of force changes every rotation cycle. Even in this case, the rotational speed difference can be obtained based on the angle of the magnetic lines of force.

  FIG. 12 is a control block diagram of the image forming apparatus A according to the present embodiment. As shown in FIG. 12, the control block of the image forming apparatus A includes a control unit 360 that controls the entire image forming apparatus A and an intermediate magnetic unit connected to an input port (not shown) of the control unit 360. A sensor 350 and a driving motor driver 180 connected to an output port (not shown) of the control unit 360 for controlling a motor for driving the photosensitive member 11 are included.

  As shown in FIG. 12, the control unit 360 includes a magnetic line angle calculation unit 362 that calculates an angle of magnetic lines formed between the magnetic assembly plate 100A on the drive shaft 110 side and the magnetic assembly plate 100B on the photoconductor 11 side. A target angle storage unit 264 that stores the target angle of the magnetic field lines, and an angle deviation calculation unit 366 that calculates a deviation between the target angle and the actual angle.

  As described above, the magnetic force line angle calculation unit 362 calculates the magnetic force line angle based on the signal input from the magnetic sensor 350 to the control unit 360. The target angle storage unit 364 stores a target angle of magnetic field lines that is a target value for feedback control. At this time, the angle of the lines of magnetic force generated at the target speed of the photoconductor 11 is measured in advance, and the angle is stored as the target angle. That is, at this target angle, the photoconductor 11 rotates at the target speed. The angle deviation calculation unit 366 calculates a deviation between the magnetic line angle calculated by the magnetic line angle calculation unit 362 and the target angle stored in the target angle storage unit 364. The control unit 360 gives a control command to the drive motor driver 180 so that the angle deviation calculated by the angle deviation calculation unit 366 becomes zero. The drive motor driver 180 controls the number of rotations of the motor that drives the photoconductor 11 based on the control command given from the control unit 360. Note that the control unit 360 may give a control command to the drive motor driver 180 so that the angle of the magnetic force lines calculated by the magnetic force line angle calculation unit 362 becomes the target angle without calculating the angle deviation. .

[Control operation of rotational drive transmission device]
A control operation of the image processing apparatus A according to the present embodiment having the above structure will be described. In the following, only the part related to the rotation control of the photosensitive member 11 of the rotation drive transmission device 100 of the image forming apparatus A will be described.

  When the drive shaft 110 rotates during image formation by the image forming apparatus A, the magnetic aggregate plate 100A rotates, and the magnetic field generated between the magnetic aggregate plate 100A and the magnetic aggregate plate 100B changes. The magnetic aggregate plate 100B fixed to the end surface of the photoconductor 11 is rotated by being pulled by the change of the magnetic field, and the photoconductor 11 is rotated. At this time, if the rotation unevenness does not occur, the magnetic sensor 350 can detect the angle (always constant) of the lines of magnetic force as shown in FIG. 11A. If the rotation unevenness occurs, the magnetic sensor 350 displays the angle shown in FIG. The angle of such magnetic field lines can be detected.

  In the control unit 360, the magnetic field line angle detection unit 362 calculates the angle of the magnetic field lines formed between the magnetic assembly plate 100A on the drive shaft 110 side and the magnetic assembly plate 100B on the photoconductor 11 side, and an angle deviation calculation unit. By 366, the deviation between the angle of the magnetic field lines and the target angle of the magnetic field lines stored in the target angle storage unit 364 is calculated. The control unit 360 sets the angle of the lines of magnetic force calculated based on the information detected by the magnetic sensor 350 so that the angle deviation is zero, that is, the target angle (the photosensitive member 11 is the target speed). The feedback control is performed so that the angle is the same as when rotating. As described above, when the angle of the lines of magnetic force reaches a preset target angle, the photoconductor 11 rotates at the target speed.

  As described above, according to the rotational drive transmission device and the image forming apparatus according to the present embodiment, the driving force from the drive shaft to the photoconductor is reliably transmitted using magnetic force, and the photoconductor is easily transferred from the drive shaft. Can be separated. Furthermore, it is only necessary to provide a magnetic sensor between the magnetic aggregate plates on the photoconductor side, so that an increase in cost can be suppressed. Since the rotating body itself is not provided with parts other than the mechanism for transmitting the driving force, it is possible to suppress an increase in cost and to achieve good rotation control because no eccentricity of the rotating shaft occurs.

  The position of the magnetic sensor 350 is not limited to the position described above. The position is not particularly limited as long as the angle of the lines of magnetic force between the magnetic aggregate plates due to the rotation of the magnetic aggregate plate 100A and the magnetic aggregate plate 100B can be detected.

<Fourth embodiment>
The image forming apparatus according to the fourth embodiment of the present invention will be described below. Detailed description of the same configuration as in the first embodiment will not be repeated here. In particular, the image forming apparatus A and the rotational drive transmission device 100 described with reference to FIGS. To describe). The rotation drive transmission device 100 of the image forming apparatus A according to the present embodiment is similar to the rotation control that combines the rotation control according to the first embodiment and the rotation control according to the second embodiment. Rotation control is performed. Hereinafter, this point will be described in detail.

[Control structure of rotary drive transmission device]
FIG. 13 shows a control structure of rotation drive transmission device 100 of image forming apparatus A according to the present embodiment. As shown in FIG. 13, a magnetic sensor 250 is provided in the direction perpendicular to the rotational axis of the magnetic aggregate plate 100A so as to face the rotational circumferential surface of the magnetic aggregate plate 100A, and the rotational axis of the magnetic aggregate plate 100B is A magnetic sensor 150 is provided in the vertical direction so as to face the rotational circumferential surface of the magnetic aggregate plate 100B.

  As described in the first embodiment, the direction of alternating magnetic lines of force is detected by the magnetic sensor 150, and the speed of the rotating body (here, the direction of the magnetic lines of force is alternately changed). The rotational speed and angular speed of the photoconductor 11 are calculated. Feedback control is performed so that the speed of the rotating body becomes the target speed. In addition to this, as described in the second embodiment, the magnetic sensor 250 detects the direction of alternating magnetic lines of force, and the rotating body is based on time information when the direction of the magnetic lines are alternately changed. (Here, the rotational speed and angular speed of the drive shaft 110) are calculated. Feedback control is performed so that the rotational speed difference between the rotational speed of the drive shaft 110 calculated by the magnetic sensor 250 and the rotational speed of the photoconductor 11 calculated by the magnetic sensor 150 becomes 0 or a constant value. Hereinafter, this rotation control will be described in detail.

  FIG. 14 is a control block diagram of the image forming apparatus A according to the present embodiment. As shown in FIG. 14, the control block of the image forming apparatus A includes a control unit 460 that controls the entire image forming apparatus A and a photoconductor side magnet connected to an input port (not shown) of the control unit 460. It includes a sensor 150, a drive shaft side magnetic sensor 250, and a drive motor driver 180 connected to an output port (not shown) of the controller 460 for controlling a motor for driving the photoreceptor 11.

  As illustrated in FIG. 14, the control unit 460 includes a rotation speed calculation unit 162 that calculates the rotation speed of the photoconductor 11, a target speed storage unit 164 that stores a target speed of the photoconductor 11, a target speed and an actual rotation. A speed deviation calculating unit 166 that calculates a deviation from the speed. Further, the control unit 460 includes a rotation speed calculation unit 262 that calculates the rotation speed of the drive shaft 110, the rotation speed of the photoconductor 11 calculated by the rotation speed calculation unit 162, and the drive shaft calculated by the rotation speed calculation unit 262. A speed difference calculation unit 462 that calculates a speed difference from the rotation speed of 110. Except for the speed difference calculation unit 462, the second embodiment is the same as the first embodiment or the second embodiment described above, and detailed description thereof will not be repeated here.

  The control unit 460 gives a control command to the drive motor driver 180 so that the speed deviation calculated by the speed deviation calculation unit 166 becomes zero. In addition, the control unit 460 causes the drive motor driver 180 so that the speed difference between the rotation speed of the drive shaft 110 calculated by the speed difference calculation unit 462 and the rotation speed of the photoconductor 11 becomes 0 or a constant value. Is given a control command. The drive motor driver 180 controls the rotational speed of the motor that drives the photoconductor 11 based on the control command given from the control unit 460.

[Control operation of rotational drive transmission device]
A control operation of the image processing apparatus A according to the present embodiment having the above structure will be described. In the following, only the part related to the rotation control of the photosensitive member 11 of the rotation drive transmission device 100 of the image forming apparatus A will be described.

  When the drive shaft 110 rotates during image formation by the image forming apparatus A, the magnetic aggregate plate 100A rotates, and the magnetic field generated between the magnetic aggregate plate 100A and the magnetic aggregate plate 100B changes. The magnetic aggregate plate 100B fixed to the end surface of the photoconductor 11 is rotated by being pulled by the change of the magnetic field, and the photoconductor 11 is rotated.

  In the control unit 460, the rotation speed detection unit 162 calculates the rotation speed of the photoconductor 11, and the speed deviation calculation unit 166 calculates the rotation speed of the photoconductor 11 and the target speed storage unit 164 of the photoconductor 11. A deviation from the target rotation speed (target speed) is calculated. The control unit 460 provides feedback so that the speed deviation becomes 0, that is, the rotational speed of the photoconductor 11 calculated based on the information detected by the magnetic sensor 150 becomes a preset target speed. Control. Further, in the control unit 460, the rotation speed detection unit 262 calculates the rotation speed of the drive shaft 110, and the speed difference calculation unit 462 calculates the speed difference between the rotation speed of the photoconductor 11 and the rotation speed of the drive shaft 110. Calculated. The control unit 460 performs feedback control so that the speed difference becomes 0 or a predetermined constant value.

  As described above, according to the rotational drive transmission device and the image forming apparatus according to the present embodiment, the feedback control for converging the rotational speed of the photosensitive member to the target speed, the rotational speed of the photosensitive member, and the rotational speed of the drive shaft. Since the feedback control is performed so that the difference between the two becomes zero or a constant value, the rotation control is further stabilized. It should be noted that even if such two types of feedback control are performed, a contradictory feedback command is not generated, or if a conflicting feedback command is generated, a rule is set in advance as to which control is prioritized. (It is the same in the following embodiments).

<Fifth embodiment>
The image forming apparatus according to the fifth embodiment of the present invention will be described below. Detailed description of the same configuration as in the first embodiment will not be repeated here. In particular, the image forming apparatus A and the rotational drive transmission device 100 described with reference to FIGS. To describe). The image forming apparatus A according to the present embodiment uses the rotation control that combines the rotation control according to the first embodiment and the rotation control according to the third embodiment described above in the rotation drive transmission device 100 or the second. The rotation control combining the rotation control according to the embodiment and the rotation control according to the third embodiment is performed. Hereinafter, the rotation control combining the rotation control according to the first embodiment and the rotation control according to the third embodiment will be described in detail.

[Control structure of rotary drive transmission device]
FIG. 15 shows a control structure of the rotational drive transmission device 100 of the image forming apparatus A according to the present embodiment. As shown in FIG. 15, a magnetic sensor 150 is provided in a direction perpendicular to the rotation axis of the magnetic assembly plate 100A so as to face the rotational circumferential surface of the magnetic assembly plate 100B, and the magnetic assembly plate 100A and the magnetic assembly plate Magnetic sensor 350 is provided between 100B and 100B. Note that when the rotation control according to the second embodiment and the rotation control according to the third embodiment are combined, a magnetic sensor 250 and a magnetic sensor 350 are provided.

  As described in the first embodiment, the direction of alternately changing magnetic lines is detected by the magnetic sensor 150, and the speed of the rotating body (here, the direction of the magnetic lines of force is alternately changed). The rotational speed and angular speed of the photoconductor 11 are calculated. Feedback control is performed so that the speed of the rotating body becomes the target speed. In addition, as described in the third embodiment, the angle of the magnetic force lines is detected by the magnetic sensor 350, and feedback control is performed so that the angle of the magnetic force lines becomes a constant value. Hereinafter, this rotation control will be described in detail.

  FIG. 16 is a control block diagram of the image forming apparatus A according to the present embodiment. As shown in FIG. 16, the control block of the image forming apparatus A includes a control unit 560 that controls the entire image forming apparatus A, and a photoconductor side magnet connected to an input port (not shown) of the control unit 560. It includes a sensor 150, an intermediate magnetic sensor 350, and a drive motor driver 180 connected to an output port (not shown) of the control unit 560 for controlling a motor for driving the photoreceptor 11.

  As illustrated in FIG. 16, the control unit 560 includes the configuration of the control unit 160 (FIG. 7) of the first embodiment and the configuration of the control unit 360 (FIG. 12) of the third embodiment. Have both. Since these calculation unit and storage unit are the same as those in the first embodiment or the third embodiment described above, detailed description thereof will not be repeated.

  The control unit 560 gives a control command to the drive motor driver 180 so that the speed deviation calculated by the speed deviation calculation unit 166 becomes zero. In addition to this, the control unit 560 gives a control command to the drive motor driver 180 so that the angle deviation calculated by the angle deviation calculation unit 366 becomes zero. The drive motor driver 180 controls the rotation speed of the motor that drives the photoconductor 11 based on the control command given from the control unit 560.

[Control operation of rotational drive transmission device]
A control operation of the image processing apparatus A according to the present embodiment having the above structure will be described. In the following, only the part related to the rotation control of the photosensitive member 11 of the rotation drive transmission device 100 of the image forming apparatus A will be described.

  When the drive shaft 110 rotates during image formation by the image forming apparatus A, the magnetic aggregate plate 100A rotates, and the magnetic field generated between the magnetic aggregate plate 100A and the magnetic aggregate plate 100B changes. The magnetic aggregate plate 100B fixed to the end surface of the photoconductor 11 is rotated by being pulled by the change of the magnetic field, and the photoconductor 11 is rotated.

  In the control unit 560, the rotation speed detection unit 162 calculates the rotation speed of the photoconductor 11, and the speed deviation calculation unit 166 stores the rotation speed of the photoconductor 11 and the target speed storage unit 164 of the photoconductor 11. A deviation from the target rotation speed (target speed) is calculated. The control unit 560 provides feedback so that the speed deviation becomes 0, that is, the rotational speed of the photoconductor 11 calculated based on the information detected by the magnetic sensor 150 becomes a preset target speed. Control. Further, in the control unit 560, the magnetic field line angle detection unit 362 calculates the angle of the magnetic field lines formed between the magnetic assembly plate 100A on the drive shaft 110 side and the magnetic assembly plate 100B on the photoconductor 11 side, and the angle deviation. The calculation unit 366 calculates the deviation between the angle of the magnetic field lines and the target angle of the magnetic field lines stored in the target angle storage unit 364. The control unit 560 performs feedback control so that the angle deviation becomes zero, that is, the angle of the magnetic force lines calculated based on the information detected by the magnetic sensor 350 becomes a preset target angle.

  As described above, according to the rotational drive transmission device and the image forming apparatus according to the present embodiment, the feedback control for converging the rotational speed of the photoconductor to the target speed and the photoconductor calculated based on the angle of the magnetic field lines. Since the feedback control is performed so that the difference between the rotation speed and the rotation speed of the drive shaft becomes a constant value, the rotation control is further stabilized.

  In the fifth embodiment described above, a magnetic sensor 250 may be provided instead of the magnetic sensor 150.

<Other variations>
It is possible to combine the first embodiment, the second embodiment, and the third embodiment described above in addition to the fourth embodiment and the fifth embodiment. For example, in the fourth embodiment, the speed difference between the rotation speed of the photoconductor 11 and the rotation speed of the drive shaft 110 calculated by the speed difference calculation section 462 by the control section 460 is 0 or a predetermined constant value. As such, feedback control may be performed. That is, in the fourth embodiment, the control unit 460 does not control the rotational speed of the photoconductor 11 to be the target speed, and the above-described speed difference is set to 0 or a predetermined constant value. Only feedback control is performed.

  The embodiment disclosed this time is merely an example, and the present invention is not limited to the embodiment described above. The scope of the present invention is indicated by each claim in the claims after taking into account the description of the detailed description of the invention, and all modifications within the meaning and scope equivalent to the wording described therein are intended. Including.

1 is a diagram illustrating an outline of a configuration of an image forming apparatus according to a first embodiment of the present invention. FIG. 2 is a diagram illustrating an outline of a configuration of a rotational drive transmission device in the image forming apparatus of FIG. FIG. 3 is a first diagram showing an outline of magnetic lines of force in the rotational drive transmission device of FIG. 2; FIG. 3 is a diagram (part 2) illustrating an outline of magnetic lines of force in the rotational drive transmission device of FIG. 2; FIG. 3 is a diagram illustrating a control structure of a rotational drive transmission device of the image forming apparatus according to the first embodiment of the present invention. It is a figure for demonstrating the function of the magnetic sensor of FIG. 1 is a control block diagram of an image forming apparatus according to a first embodiment of the present invention. It is a figure which shows the control structure of the rotational drive transmission device of the image forming apparatus which concerns on the 2nd Embodiment of this invention. 5 is a control block diagram of an image forming apparatus according to a second embodiment of the present invention. FIG. It is a figure which shows the control structure of the rotational drive transmission device of the image forming apparatus which concerns on the 3rd Embodiment of this invention. It is a figure for demonstrating the function of the magnetic sensor of FIG. FIG. 6 is a control block diagram of an image forming apparatus according to a third embodiment of the present invention. It is a figure which shows the control structure of the rotational drive transmission device of the image forming apparatus which concerns on the 4th Embodiment of this invention. FIG. 10 is a control block diagram of an image forming apparatus according to a fourth embodiment of the present invention. It is a figure which shows the control structure of the rotational drive transmission device of the image forming apparatus which concerns on the 5th Embodiment of this invention. FIG. 10 is a control block diagram of an image forming apparatus according to a fifth embodiment of the present invention.

Explanation of symbols

A image forming apparatus B image forming section D liquid crystal display section S image reading apparatus CA caster CS recording paper cassette section PA operation panel 2 primary transfer roller 4 intermediate transfer belt 5 secondary transfer roller 6 timing roller 7 fixing device 11 photoconductor 31 Drive roller 32 Roller 100 Rotation drive transmission device 100A, 100B Magnetic aggregate plate 110 Drive shaft 150 Photoconductor side magnetic sensor 250 Drive shaft side magnetic sensor 350 Intermediate part magnetic sensor 160, 260, 360, 460, 560 Controller 162, 262 Rotational speed Calculation unit 164, 264 Target speed storage unit 166, 266 Speed deviation calculation unit 180 Drive motor driver 362 Magnetic field line angle calculation unit 364 Target angle storage unit 366 Angle deviation calculation unit 462 Speed difference calculation unit

Claims (7)

A rotational drive transmission device capable of transmitting rotational driving force from a power source to a rotating body using magnetic force, and capable of separating the rotating body from the power source,
The rotational drive transmission device is
A first magnetic member provided on the power source side;
A second magnetic member provided on the rotating body side and magnetically attracting to the first magnetic member;
A detector that detects at least one of magnetism generated by the first magnetic member, magnetism generated by the second magnetic member, and magnetism formed between the first magnetic member and the second magnetic member. When,
A rotational drive transmission device including a control unit that controls the power source based on magnetism detected by the detection unit. The detection unit detects magnetism generated by the second magnetic member,
The control unit calculates a rotation speed on the rotating body side based on magnetism generated by the second magnetic member detected by the detection section, and the power so that the rotation speed on the rotating body side becomes a target speed. The rotational drive transmission device according to claim 1 which controls a source. The detector detects magnetism generated by the first magnetic member;
The control unit calculates a rotational speed on the power source side based on magnetism generated by the first magnetic member detected by the detection unit, and the rotational speed on the power source side is set to a target speed and the rotating body side. The rotational drive transmission device according to claim 1, wherein the power source is controlled so that a rotation speed of the power source becomes any one of a target speed. The detection unit detects magnetism formed between the first magnetic member and the second magnetic member,
The control unit calculates an angle of lines of magnetic force formed between the first magnetic member and the second magnetic member based on magnetism detected by the detection unit, and the detected angle is the rotation The rotational drive transmission device according to claim 1, wherein the power source is controlled so as to have an angle at which the body rotates at a target speed. The detection unit detects magnetism generated by the first magnetic member and magnetism generated by the second magnetic member;
The control unit calculates a rotation speed on the rotating body side based on magnetism generated by the second magnetic member detected by the detection unit, so that the rotation speed on the rotating body side becomes a target speed, and The rotational speed on the power source side is calculated based on the magnetism generated by the first magnetic member detected by the detector, and the difference between the rotational speed on the rotating body side and the rotational speed on the power source side is calculated. The rotational drive transmission device according to claim 1, wherein the power source is controlled to have a predetermined value.   6. An image forming apparatus capable of forming an electrostatic latent image on an electrostatic latent image carrier and developing the electrostatic latent image to form a toner image. An image forming apparatus for transmitting a rotational driving force from a power source included in the image forming apparatus to a rotating body using a rotational drive transmission apparatus.   The image forming apparatus according to claim 6, wherein the rotating body is a photoconductor that carries the electrostatic latent image.

Images