JP2010175984A - Image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image forming apparatus that prevents a situation wherein components of drive transmissions are damaged, when load torque applied on an operation unit for stirring or carrying toner is increased abnormally. <P>SOLUTION: The image forming apparatus 1 includes: a toner cartridge 5 for receiving the toner; a stirring member 501 for stirring the toner by arranging and rotating at least part of the stirring member 501 in the toner cartridge 5; a motor 520 for output of rotary driving force; a transmission gear train 510 for connecting the operation unit with the motor, and also for transmitting the torque, which is output from the motor, to the operation unit; a rotation detecting member 540, which is arranged in the transmission gear train, for detecting the rotation in the operation unit; and a torque limiter 530, which is arranged in the upstream side more than the rotation detecting member in the transmission direction of the rotary driving force in the transmission gear train, for shutting off the transmission of the driving force from the motor side to the operation unit side, when the load torque exceeds a predetermined value. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an image forming apparatus including an operation unit that stirs or conveys toner.

  Conventionally, in an image forming apparatus such as a printer, no toner remaining amount detecting means is provided in the developing device, and toner is continuously supplied from the toner container (toner cartridge) to the developing device during operation of the device. There is.

JP 2002-148886 A

  In such an image forming apparatus, for example, an abnormality such as toner solidifying in a toner container may occur. Due to such an abnormality, the load torque applied to the operating unit that stirs or conveys the toner in the toner container may become abnormally high.

  When such an abnormality occurs, the motor that is the drive source of the operating unit is locked, and the abnormality of the motor is detected. Alternatively, an excessive load is applied to the drive transmission unit that connects the motor and the operation unit, the drive transmission unit is damaged, and the machine stops. Conventionally, an abnormality such as toner solidification can be found only by either detecting an abnormality due to a motor lock or stopping the machine due to damage to the drive transmission unit.

  In order to avoid a situation where the motor is locked and an abnormality is detected, a measure to adopt a high-quality motor that can be driven even at high torque can be considered. However, if an attempt is made to drive a high load torque with a large driving torque exceeding the high load torque, it is inevitable that an excessive load is applied to the drive transmission unit. As a result, the risk of causing damage to the drive transmission unit increases.

  Further, a measure for providing a toner remaining amount detecting means in the developing device can be considered. In this case, when the toner remaining amount detecting means detects a decrease in the toner remaining amount, the toner is supplied from the toner container to the developing device. However, when the toner container is abnormal and the load torque applied to the operating portion becomes abnormally high, the same problem as described above occurs.

  It is an object of the present invention to provide an image forming apparatus capable of avoiding a situation in which parts such as a drive transmission unit are damaged when a load torque applied to an operation unit that stirs or conveys toner is abnormally high. Objective.

  The present invention includes a storage unit that stores toner, an operation unit that stirs and / or conveys the toner by being at least partially disposed and rotated in the storage unit, a motor that outputs a rotational driving force, The motor and the operation unit are connected to each other, and a drive transmission unit that transmits the rotational force output from the motor to the operation unit, and a rotation detection that is disposed in the drive transmission unit and detects rotation in the operation unit. A member and an upstream side of the rotation detection member in the transmission direction of the rotational driving force in the drive transmission unit, and when the load torque exceeds a predetermined value, the motor side to the operating unit side The present invention relates to an image forming apparatus including a blocking member that blocks transmission of driving force.

  In addition, when the rotation detection member does not detect rotation in the operating unit during the operation of the motor, the blocking detection unit detects that the blocking member has blocked transmission of the driving force, and the blocking detection unit It is preferable to further include a display member that displays a predetermined message when the blocking member detects that the transmission of the driving force is blocked.

  The drive transmission unit includes a transmission gear train that transmits a driving force by a plurality of gears from the motor to the operation unit, and the blocking member is a transmission between two predetermined gears in the transmission gear train. The torque limiter is preferably configured to block

  The rotation detection member is preferably composed of a pulse board and a sensor.

  According to the present invention, it is possible to avoid a situation in which components such as the drive transmission unit are damaged when the load torque applied to the operating unit that stirs or conveys the toner is abnormally high.

FIG. 2 is a layout diagram illustrating a printer as an embodiment of an image forming apparatus according to the present invention and illustrating the layout of each component in the printer. FIG. 3 is a perspective view illustrating a toner stirring structure in a toner cartridge of a printer. FIG. 4 is a schematic view showing a rotating shaft of a transmission gear train on the same plane in a toner stirring structure. It is a block diagram which shows the input side and output side of a interruption | blocking detection part.

Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings.
With reference to FIG. 1, the overall structure of a printer 1 as an image forming apparatus in the present embodiment will be described. FIG. 1 is a diagram for explaining the arrangement of each component of the printer 1.

  As shown in FIG. 1, a printer 1 as an image forming apparatus includes an apparatus main body M, and an image forming unit that forms a predetermined toner image on a sheet T as a sheet-like transfer material based on predetermined image information. And a paper supply / discharge unit that supplies the paper T to the image forming unit and discharges the paper T on which the toner image is formed.

  As shown in FIG. 1, the image forming unit includes a photosensitive drum 2 as an image carrier (photosensitive member), a charging unit 10, a laser scanner unit 4 as an exposure unit, a developing device 16, and a toner cartridge 5. A toner supply unit 6, a drum cleaning unit 11, a static eliminator 12, a transfer roller 8, and a fixing unit 9.

  As shown in FIG. 1, the paper supply / discharge unit includes a paper feed cassette 52, a manual paper feed unit 64, a conveyance path L for paper T, a registration roller pair 80, and a paper discharge unit 50.

Hereinafter, each configuration of the image forming unit and the paper supply / discharge unit will be described in detail.
First, the image forming unit will be described.
In the image forming unit, charging by the charging unit 10, exposure by the laser scanner unit 4, development by the developing device 16, transfer by the transfer roller 8, removal from the surface of the photosensitive drum 2 in order from the upstream side to the downstream side Static elimination by the electric device 12, cleaning by the drum cleaning unit 11, and fixing by the fixing unit 9 are performed.

  The photosensitive drum 2 is made of a cylindrical member and functions as a photosensitive member or an image carrier. The photosensitive drum 2 is disposed so as to be rotatable in the direction of an arrow about an axis extending in a direction orthogonal to the conveyance direction of the paper T in the conveyance path L. An electrostatic latent image is formed on the surface of the photosensitive drum 2.

  The charging unit 10 is disposed to face the surface of the photosensitive drum 2. The charging unit 10 uniformly charges the surface of the photosensitive drum 2 to be negative (minus polarity) or positive (plus polarity).

  The laser scanner unit 4 functions as an exposure unit, and is disposed away from the surface of the photosensitive drum 2. The laser scanner unit 4 includes a laser light source (not shown), a polygon mirror, a polygon mirror driving motor, and the like.

  The laser scanner unit 4 scans and exposes the surface of the photosensitive drum 2 based on image information output from an external device such as a PC (personal computer). By performing scanning exposure by the laser scanner unit 4, electric charges charged on the surface of the photosensitive drum 2 are removed. As a result, an electrostatic latent image is formed on the surface of the photosensitive drum 2.

  The developing device 16 is provided corresponding to the photosensitive drum 2 and is disposed to face the surface of the photosensitive drum 2. The developing unit 16 attaches a single color (usually black) toner to the electrostatic latent image formed on the photosensitive drum 2 to develop a single color toner image (forms a toner image on the surface of the photosensitive drum). ). The developing device 16 includes a developing roller 17 that can be disposed opposite to the surface of the photosensitive drum 2, a stirring roller 18 for stirring the toner, and the like.

  The toner cartridge 5 is provided corresponding to the developing device 16 and stores toner supplied to the developing device 16.

  The toner supply unit 6 is provided corresponding to the toner cartridge 5 and the developing device 16, and supplies the toner contained in the toner cartridge 5 to the developing device 16.

  The transfer roller 8 transfers the toner image developed on the surface of the photosensitive drum 2 to the paper T. A transfer bias for transferring the toner image developed on the photosensitive drum 2 to the paper T is applied to the transfer roller 8 by a voltage application unit (not shown).

  The transfer roller 8 is brought into contact with and separated from the photosensitive drum 2. Specifically, the transfer roller 8 is configured to be movable between a contact position where the transfer roller 8 is in contact with the photosensitive drum 2 and a spaced position where the transfer roller 8 is separated from the photosensitive drum 2. Specifically, the transfer roller 8 is moved to the contact position when the toner image developed on the photosensitive drum 2 is transferred to the paper T, and is moved to the separation position in other cases.

  A sheet T conveyed on the conveyance path L is sandwiched between the photosensitive drum 2 and the transfer roller 8. The sandwiched paper T is pressed against the surface of the photosensitive drum 2. A transfer nip N is formed between the photosensitive drum 2 and the transfer roller 8. In the transfer nip N, the toner image developed on the photosensitive drum 2 is transferred onto the paper T.

  The static eliminator 12 is disposed to face the surface of the photosensitive drum 2. The static eliminator 12 irradiates the surface of the photosensitive drum 2 with light, thereby neutralizing the surface of the photosensitive drum 2 after the transfer is performed (removing the electric charge).

  The drum cleaning unit 11 is disposed to face the surface of the photosensitive drum 2. The drum cleaning unit 11 removes toner and deposits remaining on the surface of the photosensitive drum 2, and transports the removed toner to a predetermined recovery mechanism for recovery.

  The fixing unit 9 melts the toner constituting the toner image transferred onto the paper T and fixes it on the paper T. The fixing unit 9 includes a heating roller 9a heated by a heater and a pressure roller 9b pressed against the heating roller 9a. The heating roller 9a and the pressure roller 9b convey the paper T onto which the toner image has been transferred so as to sandwich the paper T. When the paper T is conveyed so as to be sandwiched between the heating roller 9a and the pressure roller 9b, the toner transferred onto the paper T is melted and fixed on the paper T.

Next, the paper supply / discharge unit will be described.
As shown in FIG. 1, in the lower part of the apparatus main body M, a single paper feed cassette 52 that stores paper T is disposed. The paper feed cassette 52 is configured to be drawable from the apparatus main body M in the horizontal direction. In the paper feed cassette 52, a placement plate 60 on which the paper T is placed is disposed. In the paper feed cassette 52, the paper T is stored in a state of being stacked on the placement plate 60. The paper T placed on the placement plate 60 is sent out to the transport path L by the cassette paper feed unit 51 arranged at the end of the paper feed cassette 52 on the paper feed side (the left end in FIG. 1). The cassette paper feed unit 51 includes a double feed prevention mechanism including a forward feed roller 61 for taking out the paper T on the placement plate 60 and a paper feed roller pair 63 for feeding the paper T to the transport path L one by one. Prepare.

  A manual paper feed unit 64 is provided on the left side surface (left side in FIG. 1) of the apparatus main body M. The manual paper feed unit 64 is provided mainly for supplying the apparatus main body M with a paper T of a size and type different from the paper T set in the paper feed cassette 52. The manual paper feed unit 64 includes a manual feed tray 65 that forms a part of the apparatus main body M in the closed state, and a paper feed roller 66. The lower end of the manual feed tray 65 is attached to the vicinity of the paper feed roller 66 so as to be rotatable (openable and closable). The paper T is placed on the open manual feed tray 65. The manual paper feed unit 64 feeds the paper T placed on the open manual feed tray 65 to the manual feed path La.

  A paper discharge unit 50 is provided on the upper side of the apparatus main body M. The paper discharge unit 50 discharges the paper T to the outside of the apparatus main body M. Details of the paper discharge unit 50 will be described later.

  The conveyance path L for conveying the paper T is a first conveyance path L1 from the cassette paper feeding unit 51 to the transfer roller 8, a second conveyance path L2 from the transfer roller 8 to the fixing unit 9, and a discharge from the fixing unit 9. A third conveyance path L3 to the section 50, a manual conveyance path La that joins the paper supplied from the manual sheet feeding unit 64 to the first conveyance path L1, and a third conveyance path L3 from the upstream side to the downstream side. And a return transport path Lb that reverses the paper and returns it to the first transport path L1.

Moreover, the 1st junction part P1 and the 2nd junction part P2 are provided in the middle of the 1st conveyance path L1. A first branch portion Q1 is provided in the middle of the third transport path L3.
The first joining part P1 is a joining part where the manual feed path La joins the first transport path L1. The second junction P2 is a junction where the return conveyance path Lb merges with the first conveyance path L1.
The first branch portion Q1 is a branch portion where the return transport path Lb branches from the third transport path L3.

  In the middle of the first transport path L1 (specifically, between the second junction P2 and the transfer roller 8), a sensor for detecting the paper T, skew correction (slanting paper feeding) of the paper T, and toner A registration roller pair 80 is arranged for matching the timing with the image. The sensor is disposed immediately before (on the upstream side) the registration roller pair 80 in the transport direction of the paper T. The registration roller pair 80 conveys the paper T by performing the above-described correction and timing adjustment based on detection information from the sensor.

  The return conveyance path Lb is a conveyance path that is provided so that the opposite surface (non-printing surface) to the surface that has already been printed faces the photosensitive drum 2 when performing duplex printing on the paper T. According to the return transport path Lb, the paper T transported from the first branching section Q1 to the paper discharge section 50 side is reversed and returned to the first transport path L1, and the resist disposed on the upstream side of the transfer roller 8 is returned. It can be conveyed to the upstream side of the roller pair 80. A predetermined toner image is transferred onto the non-printing surface by the photosensitive drum 2 on the paper T that has been turned upside down by the return conveyance path Lb.

  A paper discharge unit 50 is formed at the end of the third transport path L3. The paper discharge unit 50 is disposed on the upper side of the apparatus main body M. The paper discharge unit 50 opens toward the right side of the apparatus main body M (the right side in FIG. 1, the side opposite to the manual paper feed unit 64). The paper discharge unit 50 discharges the paper T conveyed on the conveyance path L3 to the outside of the apparatus main body M.

On the opening side of the paper discharge unit 50, a paper discharge stacking unit M1 is formed. The paper discharge stacking unit M1 is formed on the upper surface (outer surface) of the apparatus main body M. The paper discharge stacking unit M1 is a portion formed by the upper surface of the apparatus main body M being depressed downward. The bottom surface of the paper discharge stacking unit M1 constitutes a part of the top surface of the apparatus main body M. In the paper discharge stacking unit M1, sheets T onto which a predetermined toner image has been transferred and discharged from the paper discharge unit 50 are stacked and stacked.
A paper detection sensor is disposed at a predetermined position on each conveyance path.

  Next, a structure for stirring the toner in the toner cartridge 5 will be described with reference to FIGS. 2 to 4 in addition to FIG.

  As shown in FIG. 1, the toner in the developing device 16 is reduced by developing the electrostatic latent image formed on the photosensitive drum 2 with toner. For this reason, the developer 16 needs to be replenished (supplemented) with toner so that the remaining amount of toner in the developer 16 is not always less than the required amount. The developing device 16 is not provided with a toner remaining amount detecting member capable of detecting the remaining amount of toner. Therefore, the printer 1 of the present embodiment is configured such that toner is constantly supplied (supplied) from the toner cartridge 5 to the developing device 16 during the operation of the printer 1.

  As shown in FIGS. 1 and 3, a stirring member 501 serving as an operation unit is provided in a toner cartridge 5 serving as a storage unit that stores toner. The stirring member 501 is at least partially disposed in the toner cartridge 5 and rotates to stir the toner. The stirring member 501 includes a central shaft 502 that extends parallel to the rotation axis of the toner supply unit 6. Further, the stirring member 501 includes, for example, a spiral plate 503 projecting spirally around the central shaft 502. FIG. 3 shows the spiral plate 503 in cross section.

Such a stirring member 501 is capable of stirring the toner stored in the cartridge 5 by being rotated about the central shaft 502. In order to rotate the stirring member 501, the end of the central shaft 502 of the stirring member 501 is connected to the motor 520 via the drive transmission unit 510.
The central shaft 502 of the stirring member 501 is rotatably supported on the wall portion of the toner cartridge 5. A coupling 504 is attached to the end of the central shaft 502 that protrudes outward (leftward in FIG. 3) from the toner cartridge 5.

  The drive transmission unit 510 that connects the output shaft 521 of the motor 520 and the central shaft 502 of the stirring member 501 is configured by a transmission gear train. In the transmission gear train 510 as a drive transmission unit, the number of gears (number) can be arbitrarily selected. In the present embodiment, for example, nine gears from the first gear to the ninth gear are used.

  The first gear 511 is attached to the output shaft 521 of the motor 520. Therefore, the output shaft 521 of the motor 520 serves as the rotation shaft of the first gear 511. The outer periphery of the first gear 511 meshes with the outer periphery of the second gear 512 having a rotation axis parallel to the rotation axis of the first gear 511. The outer periphery of the second gear 512 meshes with the outer periphery of a third gear 513 having a rotation axis parallel to the rotation axis of the second gear 512. The fourth gear 514 that meshes with the outer periphery of the third gear 513 and the next fifth gear 515 are attached to a torque limiter 530 as a blocking member.

In the torque limiter 530, the driving side 531 and the load side (driven side) 532 are arranged on the same axis. When the drive side 531 is rotated by receiving a drive torque from a drive source (for example, the motor 520), the torque limiter 530 is integrated with the drive side 531 when the rotation torque of the load side 532 is equal to or less than a set value. Rotate.
On the other hand, when the load torque exceeds the set value, the torque limiter 530 cancels the transmission state between the drive side 531 and the load side 532. Thereby, transmission of the driving force from the driving side 531 to the load side 532 in the torque limiter 530 is cut off. For this reason, when the load torque exceeds the set value, even if the drive side 531 continues to rotate, the load side 532 does not rotate and stops.

  The axis of the torque limiter 530 having such a structure is arranged in parallel with the rotation axis of the third gear 513. A fourth gear 514 that meshes with the outer periphery of the third gear 513 is attached to the drive side 531 of the torque limiter 530. A fifth gear 515 is attached to the load side (driven side) 532 of the torque limiter 530.

  The outer periphery of the fifth gear 515 meshes with the outer periphery of a sixth gear 516 having a rotation axis parallel to the axis of the torque limiter 530. The outer periphery of the sixth gear 516 meshes with the outer periphery of a seventh gear 517 having a rotation axis parallel to the rotation axis of the sixth gear 516. A pulse plate 541 constituting the rotation detection member 540 is attached to one end (left end in FIG. 3) of the rotation shaft 517a of the seventh gear 517. The pulse plate 541 rotates integrally with the seventh gear 517. Here, the rotation detecting member 540 detects the rotation of the pulse plate 541 that rotates in conjunction with the stirring member 501 and outputs a predetermined signal when the stirring member 501 is rotating. The rotation detection member 540 will be described later.

  An eighth gear 518 is attached to the other end (the right end in FIG. 3) of the rotation shaft 517a of the seventh gear 517. Therefore, the rotation shaft 517a of the seventh gear 517 is also used as the rotation shaft of the eighth gear 518. The outer periphery of the eighth gear 518 meshes with the outer periphery of a ninth gear 519 having a rotation axis parallel to the rotation shaft 517a of the eighth gear 518. A coupling 505 is attached concentrically with the ninth gear 519 at one end of the rotation shaft of the ninth gear 519 (the right end in FIG. 3).

The coupling 505 is biased by a coil spring 506 in a direction away from the ninth gear 519 (rightward in FIG. 3). When the coupling 505 receives an external force in the left direction in FIG. 3 by the coupling 504 of the stirring member 501, the coupling 505 is pushed in the left direction in FIG. 3 while compressing the coil spring 506. Therefore, the coupling 504 is detachably engaged with the coupling 504 attached to the end of the central shaft 502 of the stirring member 501.
The engagement state between the coupling 505 and the coupling 504 is reliably held by the biasing force of the coil spring 506. Therefore, when the ninth gear 519 is rotated, the rotational force of the coupling 505 that is rotated integrally with the ninth gear 519 is reliably transmitted from the coupling 505 to the coupling 504.

  In such a transmission gear train 510, the side where the motor 520 is located and the side where the coupling 505 is located are opposite to each other. That is, in FIG. 3, the motor 520 is disposed on the left side when viewed from the first gear 511. On the other hand, the coupling 505 is disposed on the right side when viewed from the ninth gear 519.

  The rotation detection member 540 includes a disk-shaped pulse disk 541 and a sensor (for example, an optical sensor) 543. The pulse disc 541 is attached to one end (left end in FIG. 3) of the rotation shaft 517a of the seventh gear 517 concentrically with the seventh gear 517. Near the outer periphery of the pulse board 541, a plurality of (for example, four) holes (pulse holes) 542 are arranged at equal intervals in the circumferential direction along the circumferential direction. Specifically, when the number of holes 542 is four, they are arranged at intervals of 90 ° in the circumferential direction. In FIG. 2, only two of the four holes 542 are shown. In FIG. 3, only one hole 542 is shown.

  The sensor 543 is disposed at a position where the holes 542 pass successively when the pulse plate 541 rotates. The sensor 543 detects the hole 542 passing through the position in accordance with the rotation of the pulse board 541. By detecting the hole 542, the sensor 543 detects the rotation of the pulse board 541. When the number of holes 542 in the pulse plate 541 is four, for example, the sensor 543 detects that the pulse plate 541 has made one rotation by detecting the holes 542 four times.

  When the pulse plate 541 rotates, the stirring member 501 also rotates through the eighth gear 518 and the ninth gear 519 and further through the couplings 505 and 504. Therefore, the sensor 543 detects the rotation of the pulse plate 541 by detecting the hole 542, and further detects the rotation of the stirring member 501. The sensor 543 outputs a predetermined signal in response to detection of the hole 542. Therefore, when the sensor 543 outputs a predetermined signal, it indicates that the pulse plate 541 (and hence the stirring member 501) is rotating. Further, when the sensor 543 does not output a predetermined signal, it indicates that the pulse plate 541 (and hence the stirring member 501) is not rotating.

As shown in FIG. 4, the sensor 543 is connected to a control member (for example, CPU) 550. The control member 550 includes a block detection unit 551 and a message output unit 552. Then, a predetermined signal output from the sensor 543 is input to the interruption detection unit 551 of the control member 550. A motor 520 is connected to the control member 550. Then, when the motor 520 is in operation, an electrical signal indicating that is input to the interruption detection unit 551 of the control member 550.
Therefore, when the electrical signal indicating that the shut-off detection unit 551 is operating is input from the motor 520 but the predetermined signal from the sensor 543 is not input, the torque limiter 530 is connected to the drive side 531 and the load side. It is possible to detect that transmission with 532 has been cut off.

Specifically, in a state where an electric signal indicating that the motor 520 is operating is being input, the motor 520 is shut off after a predetermined time has elapsed since the predetermined signal from the sensor 543 that has been input is no longer input. The detection unit 551 detects the interruption of transmission (release of the transmission state) by the torque limiter 530.
In addition, when the predetermined signal from the sensor 543 is not input even after a predetermined time has elapsed since the start of the motor 520 and an electric signal indicating that the motor 520 is operating is input, the interruption detection unit 551 Then, transmission interruption (release of transmission state) by the torque limiter 530 is detected.

  In response to the detection of the interruption by the interruption detection unit 551, the message output unit 552 outputs predetermined message information. The message information output from the message output unit 552 is input to an appropriate display member 555 provided in the printer 1. The display member 555 displays a predetermined message based on the input message information.

When the powder toner is stored in the toner cartridge 5 and stored for a long period of time without being externally impacted, it is as if it is solidified. Therefore, the cause of the torque limiter 530 blocking the transmission state between the drive side 531 and the load side 532 may be that the toner is solidified in the toner cartridge 5.
In such a case, for example, “Please remove the toner cartridge and shake it once” is an appropriate error message to notify the operator. This is because there is a possibility that the toner solidified in the toner cartridge 5 can be returned to the original powder state by shaking the toner cartridge 5 by the operator. If it still does not work, it is appropriate to display a message such as “Please call a service person”.

Next, the operation of the toner stirring structure as described above will be described.
First, the operation when the torque limiter 530 maintains the transmission state between the drive side 531 and the load side 532 will be described.

  When the printer 1 starts operating, the toner supply unit 6 is continuously driven during the subsequent operation of the printer 1. Thus, toner is supplied (supplied) from the toner cartridge 5 to the developing device 16 by the toner supply unit 6. At this time, the stirring member 501 is rotated via the drive transmission unit 510 by the drive of the motor 520. Accordingly, the toner accommodated in the toner cartridge 5 is agitated by the agitating member 501.

  The torque required for the stirring member 501 to stir the toner is usually equal to or less than the set value of the load torque in the torque limiter 530. Therefore, the torque limiter 530 maintains the transmission state between the drive side 531 and the load side 532. Therefore, the driving force of the motor 520 is transmitted to the stirring member 501 through the transmission gear train 510 from the first gear 511 to the ninth gear 519 sequentially. Thereby, the stirring member 501 is rotated following the driving force of the motor 520. Therefore, the toner stored in the toner cartridge 5 is constantly stirred by the stirring member 501 during the operation of the printer 1.

At this time, the pulse plate 541 of the rotation detection member 540 is rotated at a constant rotation speed in conjunction with the stirring member 501. Therefore, the sensor 543 continues to detect the holes 542 of the pulse board 541 at regular time intervals. Accordingly, the sensor 543 detects the rotation of the pulse plate 541, that is, the rotation of the stirring member 501.
The sensor 543 outputs a predetermined signal to the interruption detection unit 551 in the control member 550 at predetermined intervals. Accordingly, a predetermined signal is input to the interruption detection unit 551 at predetermined intervals. In this case, the shutoff detection unit 551 does not detect the shutoff of the torque limiter 530. As a result, the error message as described above is not displayed on the display member 555.

Next, an operation when the torque limiter 530 cancels the transmission state between the drive side 531 and the load side 532 will be described.
First, a description will be given of a case in which the load torque that has been equal to or less than the set value in the torque limiter 530 exceeds the set value for some reason during the operation of the printer 1.

  When the load torque becomes larger than the set value, the torque limiter 530 releases the transmission state between the drive side 531 and the load side 532. Then, the driving force of the motor 520 is sequentially transmitted from the first gear 511 to the fourth gear 514 of the transmission gear train 510, but is not transmitted from the fourth gear 514 to the fifth gear 515. On the other hand, since the gears 515 to 519 after the fifth gear 515 receive a large load torque exerted on the stirring member 501 from the toner side (toner cartridge 5 side), the rotation is immediately stopped.

  When the rotation of the pulse plate 541 is stopped, the output from the sensor 543 that has previously detected the holes 542 of the pulse plate 541 at a constant time interval to the interruption detection unit 551 of the control member 550 does not occur. At this time, an electric signal indicating that the motor 520 is in operation is input from the motor 520 to the interruption detection unit 551 of the control member 550. Therefore, the interruption detection unit 551 detects that there is no input from the sensor 543 even though there is an input from the motor 520. Thereby, the shut-off detection unit 551 detects that the torque limiter 530 has released the transmission state between the drive side 531 and the load side 532.

  Specifically, in a state in which there is an input from the motor 520, the interruption detection unit 551 detects the release of the transmission state by the torque limiter 530 after a predetermined time has elapsed since the output of the sensor 543 is no longer input. In response to the detection of the interruption by the interruption detection unit 551, the message output unit 552 of the control member 550 outputs a predetermined error message to the display member 555. As a result, the error message as described above is displayed on the display member 555.

That is, an error message such as “Remove the toner cartridge and shake once” is displayed on the display member 555. The operator can see this and shake the toner cartridge 5. Thus, if the toner solidified in the toner cartridge 5 returns to the original powder state, no error message is displayed after the operation of the printer 1 is resumed.
On the other hand, if it still fails, a message such as “Please call a service person” is displayed on the display member 555 after the operation of the printer 1 is resumed.

  Also, a case will be described in which the load torque in the torque limiter 530 exceeds the set value after the motor 520 is started, for example, because the toner is solidified in the toner cartridge 5 at the start of the operation of the printer 1.

  First, when the motor 520 is activated, the driving force of the motor 520 is transmitted from the first gear 511 of the transmission gear train 510 to the agitation member 501 via the ninth gear 519 sequentially. Thereby, the stirring member 501 tends to rotate following the driving force of the motor 520. However, since the load torque applied to the stirring member 501 exceeds the set limit, the load torque in the torque limiter 530 exceeds the set value before the stirring member 501 starts rotating. Therefore, the torque limiter 530 cancels the transmission state between the drive side 531 and the load side 532. Thereby, the stirring member 501 is in a state where the rotational driving force from the motor 520 is not transmitted without starting to rotate. On the other hand, the motor 520 drives the first gear 511 to the fourth gear 514 of the transmission gear train 510 with the substantial load (stirring member 501) disconnected.

  In this case, an electric signal indicating that the motor 520 is operating is input from the motor 520 to the shut-off detection unit 551 of the control member 550 simultaneously with the activation of the motor 520. On the other hand, the signal from the sensor 543 is not input to the interruption detection unit 551 of the control member 550 forever. Therefore, the interruption detection unit 551 detects that there is no input from the sensor 543 even after a predetermined time has elapsed since the input of the electric signal from the motor 520 started. Thereby, the shut-off detection unit 551 detects that the torque limiter 530 has released the transmission state between the drive side 531 and the load side 532.

  In response to the detection of the transmission release by the blocking detection unit 551, the message output unit 552 of the control member 550 outputs predetermined error message information to the display member 555. As a result, the error message as described above is displayed on the display member 555.

That is, an error message such as “Remove the toner cartridge and shake once” is displayed on the display member 555. The operator can see this and shake the toner cartridge 5. Thus, if the toner solidified in the toner cartridge 5 returns to the original powder state, no error message is displayed after the operation of the printer 1 is resumed.
On the other hand, if it still fails, a message such as “Please call a service person” is displayed on the display member 555 after the operation of the printer 1 is resumed.

  According to the present embodiment, when the load torque applied from the toner cartridge 5 side (toner side) to the stirring member 501 becomes abnormally high, the torque limiter 530 blocks the transmission state between the drive side 531 and the load side 532. Thereby, the situation where components, such as the 1st gearwheel 511-the 9th gearwheel 519 of the transmission gear train 510, are damaged can be avoided beforehand.

  Further, according to the present embodiment, when the torque limiter 530 releases the transmission state between the drive side 531 and the load side 532, the cutoff detection unit 551 detects the cutoff of the torque limiter 530. Accordingly, it is possible to reliably detect an abnormality in the load torque applied to the stirring member 501 from the toner cartridge 5 side (toner side).

  Further, according to the present embodiment, when an abnormality in load torque applied to the stirring member 501 from the toner cartridge 5 side (toner side) is detected, the display member 555 displays an error message. Thereby, the operator can take appropriate measures such as shaking the toner cartridge 5.

  Further, if the torque limiter 530 is not provided, the operation of the motor 520 must be stopped immediately when the sensor 543 detects the stop (non-rotation) of the pulse plate 541 (stirring member 501). Otherwise, the transmission gear train 510 may be damaged. However, even if the operation stop of the motor 520 is commanded at the same time that the sensor 543 detects (the stirring member 501 stops), there is a time lag until the motor 520 actually stops. Therefore, there is a risk that the transmission gear train 510 may be damaged due to excessive torque during the time lag.

  On the other hand, according to the present embodiment, since the torque limiter 530 is provided, the torque limiter 530 first releases the transmission state before the sensor 543 detects (the stirring member 501 stops). Therefore, it is not necessary to stop the operation of the motor 520 immediately after the sensor 543 detects that the stirring member 501 has been stopped. The motor 520 may be stopped at an arbitrary timing.

  As mentioned above, although preferred embodiment was described, this invention can be implemented with a various form, without being limited to embodiment mentioned above. For example, in the present embodiment, the monochrome printer 1 has been described as the image forming apparatus. However, the present invention is not limited to this, and a color printer, a copier, a facsimile, and a complex machine of these may be used.

  In this embodiment, the agitation member 501 that agitates the toner in the toner cartridge 5 is described as an example of the operation unit. However, the present invention is not limited to this. The present invention can also be applied to the stirring of the toner in the container 16.

  In this embodiment, the agitation member 501 is described as an example of the operating portion. However, the present invention is not limited to this, and for example, an appropriate conveyance member that conveys toner from the toner cartridge 5 to the developing device 16 is used. Can also be applied.

  Alternatively, a sensor for detecting the remaining amount of toner in the developing device 16 may be arranged so that the stirring member 501 is rotated only when the toner is replenished.

  Further, without providing the pulse board 541 separately, a reflection plate may be attached to the side surface of the seventh gear 517 and the rotation of the seventh gear 517 may be detected using a reflection type sensor.

  In this embodiment, the motor 520 and the coupling 505 are disposed on the opposite sides of the transmission gear train 510. However, the present invention is not limited to this, and the motor 520 and the cup are disposed on the same side of the transmission gear train 510. A ring 505 may be disposed.

DESCRIPTION OF SYMBOLS 1 ... Printer (image forming apparatus), 5 ... Toner cartridge (accommodating part), 501 ... Stirring member (operating part), 510 ... Transmission gear train (drive transmission part), 520 ... Motor, 530 ... Torque limiter (blocking member), 540... Rotation detection member, 541... Pulse board, 542 .. hole (pulse hole), 543. Blocking detection unit, 555 …… Display member

Claims (4)

A storage unit containing toner;
An operation unit that stirs and / or conveys the toner by being arranged and rotated in at least a part of the storage unit;
A motor that outputs rotational driving force;
A drive transmission unit for connecting the motor and the operation unit, and transmitting the rotational force output from the motor to the operation unit;
A rotation detecting member disposed in the drive transmission unit and detecting rotation in the operating unit;
In the transmission direction of the rotational driving force in the drive transmission unit, the driving force is arranged on the upstream side of the rotation detection member, and the driving force from the motor side to the operating unit side when the load torque exceeds a predetermined value. A blocking member for blocking transmission;
An image forming apparatus comprising: A shut-off detection unit that detects that the shut-off member shuts off transmission of the driving force when the rotation detection member does not detect rotation in the operating unit during operation of the motor;
A display member that displays a predetermined message when the blocking detection unit detects that the blocking member has blocked transmission of the driving force; and
The image forming apparatus according to claim 1, further comprising: The drive transmission unit is composed of a transmission gear train that transmits a driving force by a plurality of gears from the motor to the operating unit,
The image forming apparatus according to claim 1, wherein the blocking member includes a torque limiter that blocks transmission between two predetermined gears in the transmission gear train.   The image forming apparatus according to claim 1, wherein the rotation detection member includes a pulse board and a sensor.

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