JP3167174U - Developer cartridge - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a developing cartridge capable of suppressing the movement of a detection member even when a slight erroneous driving force is transmitted to a gear for moving the detection member. A developing cartridge has a detection member 90 that projects outward from a housing and can move between a contact position that can abut on a detection arm 122 and a separation position that is separated from the detection arm 122. The pulling spring 91 that urges the member 90 from the contact position to the separation position and the detection member 90 are brought into contact with the detection member 90 against the urging force applied from the pull spring 91. It is provided with a rotating body 80 that can rotate in a direction along the holding surface 83A, and a transmission gear 67 that transmits a driving force input from the outside to the rotating body 80. The rotating body 80 can take a first state in which the detection member 90 is held by the holding surface 83A and a second state in which the holding surface 83A is detached from the detection member 90. [Selection diagram] FIG. 7

Description

  The present invention relates to a developing cartridge.

  In general, in an image forming apparatus such as a laser printer, a developing cartridge that contains toner is detachably attached to the main body of the apparatus. As such an image forming apparatus, there is conventionally known an apparatus capable of determining whether a mounted developing cartridge is new (new article detection) (see Patent Document 1).

  Specifically, in the image forming apparatus disclosed in Patent Document 1, a swingable arm-shaped detection actuator, a spring that biases the detection actuator to a neutral position, and a swing of the detection actuator are provided on the apparatus main body side. A sensor for detection and a control device for detecting a new article based on a signal from the sensor are provided. Further, a developing cartridge mounted on the image forming apparatus includes a detection member that extends radially outward from a predetermined shaft portion, a detection gear that rotates integrally with the detection member around the shaft portion, and the detection gear. And a plurality of gears for transmitting a driving force to the developing roller and the agitator.

  In this image forming apparatus, when a new development cartridge is mounted on the apparatus main body, the detection member presses one end of the detection actuator, the detection actuator swings, and this swing is detected by the sensor. The sensor that detects the swing transmits a detection signal indicating that to the control device, and the control device determines that the developing cartridge is new based on the received detection signal.

  In this image forming apparatus, after the developing cartridge is mounted, for example, when the front cover is closed, a warming operation (rotating operation) is executed by the control device. Here, the glass turning operation refers to an operation of rotating the agitator in the cartridge to stir the toner in the developing cartridge.

  In such a glass turning operation, a driving force from a driving source provided on the apparatus main body side is transmitted to the agitator and the detection gear via a plurality of gears. As a result, the stirring of the toner by the agitator is started, and the detection member rotates to further press one end of the detection actuator, and comes off from the detection actuator at a predetermined position. Thereafter, the detection actuator returns to the neutral position by the biasing force of the spring.

Therefore, in the used developing cartridge, the position of the detection member is located at a position different from the initial position. As a result, when the used developing cartridge is removed from the apparatus main body and attached to the image forming apparatus again, the detection actuator is not pressed by the detection member in the image forming apparatus, so that the control apparatus that does not receive the detection signal is attached. It is determined that the developed cartridge is an old product.
JP 2006-267994 A

  However, in the conventional developing cartridge described above, when a plurality of gears that transmit driving force to the developing roller and the agitator are operated before using the developing cartridge, the detection member is intended in conjunction with this. There is a possibility of moving to a position that does not. Then, there arises a problem that the detection member cannot be accurately detected by the detection actuator on the main body side.

  Therefore, an object of the present invention is to provide a developing cartridge that can suppress the movement of the detection member even when an erroneous driving force is slightly transmitted to the gear that moves the detection member.

  In order to achieve the above object, a developing cartridge according to the present invention includes a housing that stores a developer, a contact position that protrudes outward from the housing and can contact the detection actuator, and is spaced apart from the detection actuator. A detection member that can move between positions; a biasing member that biases the detection member from the contact position toward the separation position; A holding surface that holds the detection member at the abutting position against the biasing force, a holding member that is movable in a direction along the holding surface, and a driving force input from the outside. A transmission gear for transmitting to the holding member, wherein the holding member takes a first state in which the detection member is held by the holding surface and a second state in which the holding surface is detached from the detection member. To get And features.

  According to the developing cartridge configured as described above, when an erroneous driving force is slightly transmitted to the transmission gear, the holding member slightly moves in the direction along the holding surface. At this time, since the detection member is held on the holding surface until the holding member is in the second state, the detection member continues to be held at a contact position where it can come into contact with the detection actuator. That is, the movement of the detection member can be suppressed because the holding surface does not come off the detection member only by moving the holding member slightly in the direction along the holding surface.

  According to the present invention, until the holding member is in the second state, the detection member continues to be held at the contact position where the detection member can come into contact with the detection actuator, so that an erroneous driving force is slightly applied to the gear that moves the detection member. Even if it is transmitted, the movement of the detection member can be suppressed.

1 is a side sectional view showing a laser printer according to an embodiment of the present invention. FIG. 4 is a side view (a) showing a state where the cover body of the developing cartridge is removed, and a side view (b) showing the cover body. It is a perspective view which shows the state which looked at the rotary body from the near left side. It is the figure (a) which shows the state which looked at the rotary body from the right side, and sectional drawing (b) of a rotary body. FIG. 6 is a cross-sectional view illustrating a state where the developing cartridge is removed from the main body casing. It is a perspective view which shows each component of a new article specification detection apparatus. It is explanatory drawing explaining operation | movement of a rotary body, explanatory drawing (a) which shows the relationship between a rotary body, a detection member, and a detection arm when a developing cartridge is mounted in a main body casing, It is explanatory drawing (b) shown, and explanatory drawing (c) which shows the state by which the support of the detection arm by the detection member was cancelled | released. Sectional drawing (a) which shows the relationship between the 2nd notch part and nail | claw part before a rotary body rotates, and sectional drawing which shows the relationship between the 2nd notch part and claw part while a rotary body is rotating ( It is sectional drawing (c) which shows the relationship between b) and the 2nd notch part and nail | claw part after a rotary body rotated predetermined amount. It is the side view (a) which shows the 1st modification of a holding member, and the side view (b) which shows the 2nd modification of a holding member.

  Next, an embodiment of the present invention will be described in detail with reference to the drawings as appropriate. In the following description, first, the overall configuration of the laser printer will be described briefly, and then the details of the features of the present invention will be described. Further, in the following description, the description will be made in the direction based on the user when the laser printer 1 is used. That is, in FIG. 1, the right side is referred to as “front side”, the left side is referred to as “back side”, the back side in the vertical direction of the paper surface is referred to as “right side”, and the front side in the vertical direction of the paper surface is referred to as “left side”. Called. As for the vertical direction, the vertical direction in the figure is referred to as the “vertical direction” as it is.

<Overall configuration of laser printer>
As shown in FIG. 1, the laser printer 1 includes a feeder unit 4 for feeding paper 3 into a main body casing 2 as an example of an image forming apparatus main body, and an image forming unit for forming an image on the paper 3. 5 etc.

<Configuration of feeder section>
The feeder unit 4 has a known structure, and mainly includes a paper feed tray 6, a paper pressing plate 7, and a paper transport mechanism 9. In the feeder unit 4, the sheet 3 in the sheet feeding tray 6 is moved upward by the sheet pressing plate 7 and conveyed to the image forming unit 5 by the sheet conveying mechanism 9.

<Configuration of image forming unit>
The image forming unit 5 includes a scanner unit 16, a process cartridge 17, a fixing unit 18, and the like.

  The scanner unit 16 includes a laser light emitting unit, a polygon mirror, a lens, a reflecting mirror, and the like (not shown). In the scanner unit 16, the laser beam is irradiated on the surface of the photosensitive drum 27 by high-speed scanning through a path indicated by a chain line in the drawing.

  The process cartridge 17 can be attached to and detached from the main casing 2 by appropriately opening the front cover 2 </ b> A on the front side of the main casing 2. The process cartridge 17 is mainly composed of a developing cartridge 28 and a drum unit 51.

  The developing cartridge 28 is detachably attached to the main body casing 2 via the drum unit 51 or is detachably attached to the drum unit 51 fixed to the main body casing 2. The developing cartridge 28 mainly includes a developing roller 31, a layer thickness regulating blade 32, a supply roller 33, and a toner hopper 34.

  In the developing cartridge 28, toner as an example of the developer in the toner hopper 34 is stirred by the agitator 34A and then supplied to the developing roller 31 by the supply roller 33. At this time, the toner between the supply roller 33 and the developing roller 31 is supplied. Positively frictionally charged. The toner supplied onto the developing roller 31 enters between the layer thickness regulating blade 32 and the developing roller 31 as the developing roller 31 rotates, and is further developed as a thin layer having a constant thickness while being frictionally charged. It is carried on a roller 31. Details of the developing cartridge 28 will be described later.

  The drum unit 51 mainly includes a known photosensitive drum 27, a scorotron charger 29 and a transfer roller 30. In the drum unit 51, the surface of the photosensitive drum 27 is uniformly positively charged by the scorotron charger 29 and then exposed by high-speed scanning of the laser beam from the scanner unit 16. Thereby, the potential of the exposed part is lowered, and an electrostatic latent image based on the image data is formed.

  Next, the toner carried on the developing roller 31 is supplied to the electrostatic latent image formed on the surface of the photosensitive drum 27 by the rotation of the developing roller 31, and the toner image is formed on the surface of the photosensitive drum 27. It is formed. Thereafter, the sheet 3 is conveyed between the photosensitive drum 27 and the transfer roller 30, whereby the toner image carried on the surface of the photosensitive drum 27 is transferred onto the sheet 3.

  The fixing unit 18 has a known structure and includes a heating roller 41 and a pressing roller 42. In the fixing unit 18, the toner transferred onto the paper 3 is thermally fixed while the paper 3 passes between the heating roller 41 and the pressing roller 42. The paper 3 thermally fixed by the fixing unit 18 is sent out onto the paper discharge tray 46 by the paper discharge roller 45.

<Detailed structure of developing cartridge>
Next, the detailed structure of the developing cartridge 28 which is a characteristic part of the present invention will be described.

  2A and 2B, the developing cartridge 28 includes the developing roller 31 and the like, and also includes a cartridge body 60 and a cover body 70 as an example of a housing.

  A gear mechanism 61 is rotatably provided on the left side surface of the cartridge body 60 for transmitting a driving force input from the outside of the developing cartridge 28 to the developing roller 31, the supply roller 33, and the agitator 34A.

  The gear mechanism 61 includes an input gear 62 to which a driving force is transmitted from a driving device 110 (see FIG. 5) provided on the main casing 2 side, a developing roller driving gear 63 and a supply roller driving gear 64 that directly mesh with the input gear 62. And an agitator drive gear 66 that meshes with the input gear 62 via an intermediate gear 65. Here, the developing roller driving gear 63, the supply roller driving gear 64, and the agitator driving gear 66 are gears for driving the developing roller 31, the supply roller 33, and the agitator 34A shown in FIG. 33 and the agitator 34A are integrally provided at the ends of the shafts.

  A transmission gear 67 that meshes directly with the agitator drive gear 66 and a rotating body 80 as an example of a holding member are rotatably provided on the right side surface of the cover body 70. Since the cover body 70 is detachably attached to the left side surface of the cartridge main body 60, the gear mechanism 61, the transmission gear 67, and the rotating body 80 are disposed between the cartridge main body 60 and the cover body 70. Become. The cover body 70 is provided with a detection spring 90 and a tension spring 91 as an example of an urging member.

  As shown in FIG. 3, the rotating body 80 includes a cylindrical inner cylinder portion 81, a gear portion 82 provided on the right side of the outer peripheral surface portion of the inner cylinder portion 81 (on the cartridge body 60 side), and an outer periphery of the inner cylinder portion 81. The outer cylinder part 83 provided so that the surface part left side may be enclosed is comprised.

  As shown in FIG. 4A, the inner cylinder portion 81 is rotatably engaged with an outer peripheral surface of a support shaft portion 71 as an example of a shaft portion that protrudes inward in the left-right direction from the inner surface of the cover body 70. ing. The support shaft portion 71 is a shaft formed in a cylindrical shape, and a claw portion 71 </ b> A as an example of an engagement piece that protrudes radially outward in part and can be deformed in the radial direction is formed. Has been. The claw portion 71 </ b> A is engaged with the axially inner end surface of the gear portion 82 of the rotating body 80, so that the rotating body 80 is prevented from coming off from the support shaft portion 71.

  A gear tooth portion 82 </ b> A that meshes with the transmission gear 67 is formed on a part of the outer peripheral surface of the gear portion 82. Of the outer peripheral surface of the gear portion 82, the portion where the gear tooth portion 82 </ b> A is not formed is a missing tooth portion 82 </ b> B that is not in contact (impossible to engage) with the transmission gear 67.

  A cylindrical wall 82 </ b> C that protrudes inward in the left-right direction is formed on the right end surface of the gear portion 82 so as to surround the support shaft portion 71. The cylindrical wall 82C is formed with a first notch 82D and a second notch 82E as an example of an engagement groove. The position of the rotating body 80 is maintained by engaging the claw portion 71A with the first notch portion 82D or the second notch portion 82E.

  Specifically, the first cutout portion 82D is a portion that engages with the claw portion 71A when the developing cartridge 28 is in a new state, and the second cutout portion 82E rotates the rotating body 80 by a predetermined amount due to the glass turning operation. It is a portion that sometimes engages with the claw portion 71 </ b> A and maintains the missing tooth portion 82 </ b> B of the rotating body 80 at a position facing the transmission gear 67. The gear tooth portion 82A and the missing tooth portion 82B are formed at a predetermined ratio so that the relationship between the claw portion 71A, the first notch portion 82D, and the second notch portion 82E is the above-described relationship.

  As shown in FIG. 4B, the outer cylinder portion 83 is a circle centered on the rotation center of the rotating body 80 (outer cylinder portion 83) when viewed from the direction of the rotating shaft (support shaft portion 71) of the rotating body 80. It is formed in an arc shape. The outer peripheral surface of the outer cylindrical portion 83 includes a holding surface 83A having an arc shape and a flat portion 83B that connects both ends of the holding surface 83A (arc).

  The rotating body 80 configured as described above can move in the direction along the arc shape of the holding surface 83A by rotating counterclockwise as shown in FIG. 4B around the support shaft portion 71. Thus, a first state in which a detection member 90 described later is held on the holding surface 83A and a second state in which the holding surface 83A is detached from the detection member 90 can be taken.

  The detection member 90 has a substantially quadrangular prism shape (see FIG. 3), is attached to an opening 72 formed in the cover body 70 so as to be slidable in the front-rear direction, and has a front surface (front surface) and an opening 72. A tension spring 91 is provided between the front end and the front end. The detection member 90 has a right end portion disposed between the cover body 70 and the cartridge body 60, and a left end portion disposed so as to protrude outward in the left-right direction from the opening 72 of the cover body 70.

  As shown in FIG. 4B, the detection member 90 is held on the back side of the opening 72 by the front lower portion of the right end being in contact with and held by the holding surface 83 </ b> A of the rotating body 80. The rear surface (surface on the back side) of the left end portion is maintained at a contact position where it can come into contact with a detection arm 122 to be described later, against the urging force applied from.

  Then, when the rotating body 80 is in the second state, specifically, when the rotating body 80 is rotated and the flat portion 83B is directed upward in FIG. 4B and becomes substantially horizontal (FIG. 7C )), The holding surface 83A is detached from the right end portion of the detection member 90. Then, the detection member 90 is pulled to the near side of the opening 72 along the plane portion 83 </ b> B by the pulling spring 91, and moves to a separation position where the left end portion is separated from the detection arm 122.

  As shown in FIG. 5, a drive device 110 and a new product specification detection device 120 are provided in the main body casing 2. These are briefly described below.

  In the portion of the main casing 2 where the developing cartridge 28 is mounted, a driving device 110 that transmits driving force to the input gear 62 of the developing cartridge 28 and a new specification detection that detects whether the developing cartridge 28 is new or not. A device 120 is provided.

  The drive device 110 includes a plurality of gears and a drive motor (not shown). Then, when the developing cartridge 28 is mounted in the main casing 2, the gear on the driving device 110 side meshes with the input gear 62, so that the driving force from the driving motor is transmitted to the input gear 62 via each gear. The In the drive device 110, a gear that meshes with the input gear 62 is configured to advance and retract with respect to the input gear 62 in conjunction with opening and closing of the front cover 2 </ b> A, for example.

  As shown in FIG. 6, the new product specification detection device 120 mainly includes an optical sensor 121, a detection arm 122 and a coil spring 123 as an example of a detection actuator, and a control device 124.

  The optical sensor 121 is a sensor that detects the swing of the detection arm 122, and outputs a predetermined signal to the control device 124 when the light from the light emitting unit 121 </ b> A is received by the light receiving unit 121 </ b> B.

  The detection arm 122 includes a cylindrical portion 122A that is rotatably supported by the main body casing 2, a light shielding arm 122B that extends radially outward from the cylindrical portion 122A, and a contact arm 122C. It is configured to be swingable about the portion 122A. In addition, a coil spring 123 is attached to an appropriate position of the light shielding arm 122B of the detection arm 122, whereby the detection arm 122 is constantly biased to the neutral position by the coil spring 123. And in this neutral position, the front-end | tip part 122D of the arm 122B for light shielding is arrange | positioned between the light emission part 121A and the light-receiving part 121B. Further, in the neutral position, the distal end portion 122E of the contact arm 122C is disposed at a position where it can contact the detection member 90 at the contact position protruding from the outer surface of the developing cartridge 28 attached to the main casing 2. .

  The control device 124 determines whether or not the developing cartridge 28 is new according to the presence or absence of the swing of the detection arm 122 detected by the optical sensor 121, and the detection arm from the start of driving of the driving device 110. A function of discriminating the specifications of the developing cartridge 28 according to the time required for the 122 to return to the original position is provided. Specifically, the control device 124 executes a known glass turning operation based on a closing signal from a sensor for detecting the closing operation of the front cover 2A or a signal generated when the laser printer 1 is turned on. . Then, the control device 124 determines whether or not it is a new product by determining whether or not the ON signal output from the optical sensor 121 is received when the detection arm 122 is pressed by the detection member 90. I do. In addition, the control device 124 receives the ON signal that is continuously output from the optical sensor 121 when the detection arm 122 is tilted from the original posture (the detection arm 122 is restored from the start of the rattling operation). Based on the determination of whether the maximum number of images to be formed is 3000 or 6000, based on the time until the ON signal from the optical sensor 121 is turned off after returning to the posture. I do.

  Next, operations of the rotating body 80 and the detection member 90 when the developing cartridge 28 is mounted on the main casing 2 will be described.

  As shown in FIG. 5, when a new developing cartridge 28 is installed in the main casing 2, the detection member 90 in the contact position is moved to the lower end of the detection arm 122 as shown in FIG. It abuts (the front end 122E of the abutting arm 122C). Then, the detection arm 122 is pressed by the detection member 90, and the lower end portion of the detection arm 122 moves to the back side together with the detection member 90 (developing cartridge 28).

  When the detection arm 122 swings in this way, an ON signal is output from the optical sensor 121 to the control device 124, and the control device 124 determines that it is new. Thereafter, when a known gear turning operation is executed by the control device 124, the driving force of the driving device 110 is changed to the input gear 62, the intermediate gear 65, the agitator driving gear 66, and the transmission gear 67 as shown in FIG. And transmitted to the rotating body 80 via the gear tooth portion 82A, and the rotating body 80 rotates clockwise as shown in FIG.

  At this time, since the holding surface 83A of the rotating body 80 is formed in an arc shape centered on the rotation center of the rotating body 80, the detection member 90 is kept being held on the holding surface 83A of the rotating body 80. It will continue to be held in the contact position. Thereby, since the detection member 90 continues to support the detection arm 122, the detection arm 122 does not return to the original position. In this way, the detection arm 122 is maintained in a posture inclined from the initial position, so that the ON signal described above continues to be output to the control device 124.

  Thereafter, when the rotating body 80 further rotates and the flat portion 83B of the rotating body 80 reaches a substantially horizontal position shown in FIG. 7C, as shown in FIG. 7C, the holding surface 83A detects. When the detection member 90 is detached from the member 90 and pulled by the pulling spring 91 along the flat portion 83B, the detection member 90 moves from the contact position to the separation position. Thereby, the support of the detection arm 122 by the detection member 90 is released, and the detection arm 122 is returned to the neutral position by the coil spring 123. At this time, the gear tooth portion 82A of the rotating body 80 is disengaged from the transmission gear 67, and the rotation of the rotating body 80 is stopped.

  As described above, when the detection arm 122 returns to the neutral position, the light shielding arm 122B of the detection arm 122 returns to the original position, the light from the light emitting unit 121A is blocked, and the optical sensor 121 is in the OFF state. Thus, transmission of the ON signal to the control device 124 is stopped. As a result, the reception time of the ON signal from the optical sensor 121 is calculated, and the control device 124 determines the specification based on this reception time. Note that this reception time can be changed, for example, by changing the initial position of the rotating body 80 to the position shown in FIG. 7A and the position shown in FIG. By changing the length in the circumferential direction, the time for supporting the detection arm 122 by the detection member 90 can be changed according to the specification.

  As described above, before the rotating body 80 rotates, as shown in FIG. 8A, the first cutout portion 82D of the cylindrical wall 82C formed on the right end surface of the gear portion 82 has a support shaft portion. 71 is engaged with a claw portion 71 </ b> A formed in 71. When a predetermined driving force is transmitted from the transmission gear 67 to the rotating body 80, the rotating body 80 (cylindrical wall 82C) deforms the claw portion 71A radially inward as shown in FIG. 8B. The claw portion 71A rotates while being in sliding contact with the inner peripheral surface of the cylindrical wall 82C. Thereafter, as shown in FIG. 8C, the second notch portion 82E of the cylindrical wall 82C is engaged with the claw portion 71A. Accordingly, the rotation of the rotating body 80 is reliably stopped at the position shown in FIG. 7C, and the rotating body 80 is held in a posture in which the missing tooth portion 82 </ b> B faces the transmission gear 67.

  According to the above, the following effects can be obtained in the present embodiment.

  Until the rotating body 80 is in the second state, the detection member 90 is continuously held at the contact position where it can contact the detection arm 122. Thereby, an artificial force is applied to any gear of the gear mechanism 61 or the transmission gear 67, or the driving force by the driving device 110 is transmitted for a short period of time. Even if the driving force is transmitted slightly, the movement of the detection member 90 can be suppressed, so that a new article can be detected reliably.

  Since the holding surface 83A is formed in an arc shape centered on the rotation center of the rotating body 80 when viewed from the rotation axis direction of the rotating body 80, the holding surface 83A is located with respect to the detection arm 122 when the rotating body 80 rotates. It can slide smoothly and can suppress the generation of abnormal noise. Further, the specification detection can be performed by appropriately setting the length of the holding surface 83A in the circumferential direction according to the specification.

  Since the second notch portion 82E of the cylindrical wall 82C is engaged with the claw portion 71A of the support shaft portion 71, the posture of the rotating body 80 is maintained with the missing tooth portion 82B facing the transmission gear 67. The malfunction of the rotating body 80 due to the transmission gear 67 meshing with the gear tooth portion 82A of the body 80 again can be suppressed. Moreover, since the position of the rotary body 80 (plane part 83B) is hold | maintained in a 2nd state because the 2nd notch part 82E engages with the nail | claw part 71A, the detection member which moves to a separation | spacing position from a contact position 90 and the flat portion 83B can be prevented from contacting, and the detection member 90 can be moved smoothly (see FIG. 7C).

  In addition, this invention is not limited to the said embodiment, It can utilize with various forms so that it may illustrate below.

  In the said embodiment, although the example which employ | adopted the rotary body 80 was shown as an example of a holding member, the holding member of this invention is not limited to this. For example, as shown in FIG. 9A, the holding member 183A is formed in a flat shape, and is configured to be linearly movable in the direction along the holding surface 183A (up and down in FIG. 9A). 180 may be adopted.

  Specifically, the holding member 180 is formed in a plate shape that is long in the vertical direction, and the upper surface on the back side is a holding surface 183A that contacts the detection member 90 in the first state shown in FIG. A rack gear tooth portion 182 is formed on the front surface of the holding member 180 and meshes with the first gear 168 of the transmission gear 167. Here, the transmission gear 167 includes a first gear 168 and a second gear 169 having the same rotation center as the first gear and rotating integrally with the first gear 168. The second gear 169 has a gear tooth portion 169A that meshes with the agitator drive gear 66, and a missing tooth portion 169B in which the gear tooth portion 169A is not formed.

  The operation of the holding member 180 configured as described above will be briefly described. When a new developing cartridge 28 is mounted in the main casing 2, the detection member 90 at the contact position contacts the detection arm 122. . Then, when the gear-turning operation is executed, the driving force of the driving device 110 is transmitted to the transmission gear 167 via the gear mechanism 61 and the gear tooth portion 169A of the second gear 169, and the first gear 168 is moved to FIG. ), And the holding member 180 moves downward.

  Since the detection member 90 is in the contact position while being held on the holding surface 183A of the holding member 180, it continues to support the detection arm 122, and the detection arm 122 does not return to the original position. When the holding member 180 moves further downward and the holding surface 183A is detached from the detection member 90, the detection member 90 is pulled to the near side by the pulling spring 91 and moves from the contact position to the separation position. Thereby, the support of the detection arm 122 by the detection member 90 is released, and the detection arm 122 returns to the neutral position. At this time, the gear tooth portion 169A of the second gear 169 is disengaged from the agitator drive gear 66, the agitator drive gear 66 and the missing tooth portion 169B face each other, and the rotation of the transmission gear 167 is stopped.

  According to such a holding member 180, the detection member 90 is continuously held in the contact position until the holding surface 183A is in the second state in which the holding surface 183A is detached from the detection member 90, so that an erroneous driving force is slightly transmitted. Even if it is a case, the movement of the detection member 90 can be suppressed and a new article detection can be performed reliably. In addition, since the holding surface 183A is formed in a planar shape, the holding surface 183A and the detection member 90 are in surface contact, so that the detection member 90 can be stably held at the contact position.

  As another example of the holding member of the present invention, a holding member 280 as shown in FIG. 9B may be employed. In the holding member 280, a rod-like holding portion 283 having a holding surface 283A and a rack gear tooth portion 282 that meshes with the first gear 168 of the transmission gear 167 are integrally configured. In the first state shown in FIG. 9B, the holding member 280 is engaged with a through hole (reference numeral omitted) formed in the detection member 290, so that the detection member 290 is brought into a contact position. Hold on.

  And while the holding | maintenance part 283 is engaged with the through-hole of the detection member 290, since the detection member 290 exists in a contact position, it can continue supporting the detection arm 122 in the rock | fluctuated state. When the holding member 280 moves downward and the holding portion 283 (holding surface 283A) is removed from the through hole of the detection member 290, the detection member 290 moves from the contact position to the separation position, and the detection arm 122 by the detection member 290 is detected. Is released, and the detection arm 122 returns to the neutral position.

  According to such a holding member 280, the detection member 290 is continuously held in the contact position until the holding surface 283A is in the second state in which the holding surface 283A is removed from the through hole of the detection member 290. Even if it is transmitted, the movement of the detection member 290 can be suppressed, and a new article detection can be performed reliably. Further, since the holding portion 283 is configured to be engaged with the through hole of the detection member 290, the detection member 290 can be stably held at the contact position.

  In the above embodiment, the holding surface 83A having a continuous surface is illustrated, but the holding surface of the present invention is not limited to this. That is, the holding surface of the present invention is not limited to a continuous surface, and may be a discontinuous surface. For example, the holding surface 83A of the rotating body 80 of the above embodiment may have a configuration in which a recess such as a groove is formed at a predetermined interval, or a configuration in which a gear tooth portion is formed.

  In the embodiment, the claw portion 71A as an example of the engagement piece is formed in the support shaft portion 71 (shaft portion), and the second as an example of the engagement groove in the cylindrical wall 82C of the rotating body 80 (gear portion 82). Although the notch 82E is formed, the present invention is not limited to this. For example, a claw portion (engagement piece) that can be bent and deformed in the radial direction may be formed in the cylindrical wall 82 </ b> C of the embodiment, and a notch portion (engagement groove) may be formed in the support shaft portion 71.

  In the embodiment, the example in which the tension spring 91 is employed as an example of the urging member has been described. However, the urging member of the present invention is not limited thereto, and for example, a torsion spring or a push spring may be employed. .

  In the above embodiment, the gear mechanism 61 is provided in the cartridge body 60, and the transmission gear 67 and the rotating body 80 are provided in the cover body 70. However, the present invention is not limited to this. 67 and the rotating body 80 may be provided in the cartridge main body 60 together with the gear mechanism 61.

  The number and layout of each gear in the embodiment can be changed as appropriate. For example, in the above-described embodiment, the transmission gear 67 and the rotating body 80 are meshed, but the present invention is not limited to this, and a predetermined number of gears may be provided between them. Further, the rotating body 80 may be coupled to the intermediate gear 65 directly or via a predetermined number of gears.

  Note that the transmission gear of the present invention is not limited to the transmission gears 67 and 167 of the above-described embodiment as long as the driving force input from the outside is transmitted to the holding member. For example, when the rotating body 80 is directly connected to the intermediate gear 65, the intermediate gear 65 serves as a transmission gear.

  In the above-described embodiment, the present invention is applied to the laser printer 1. However, the present invention is not limited to this, and the present invention may be applied to other image forming apparatuses such as a copying machine and a multifunction machine.

28 Developing Cartridge 60 Cartridge Body 67 Transmission Gear 70 Cover Body 71 Support Shaft 71A Claw 80 Rotating Body 82A Gear Tooth 82B Missing Tooth 82E Second Notch 83A Holding Surface 90 Sensing Member 91 Pulling Spring 122 Sensing Arm 123 Coil Spring 167 Transmission gear 180 Holding member 183A Holding surface 280 Holding member 283A Holding surface 290 Detection member

Claims (4)

A housing for containing the developer;
A detection member that protrudes outward from the housing and is movable between a contact position that can contact the detection actuator and a separation position that is separated from the detection actuator;
A biasing member that biases the detection member from the contact position toward the separation position;
By having contact with the detection member, it has a holding surface that holds the detection member at the contact position against the urging force applied from the urging member and moves in a direction along the holding surface. Possible holding members;
A transmission gear for transmitting a driving force input from the outside to the holding member,
The developing cartridge, wherein the holding member can take a first state in which the detection member is held on the holding surface and a second state in which the holding surface is detached from the detection member. The holding member is a rotating body provided rotatably on the housing.
The developing cartridge according to claim 1, wherein the holding surface is formed in an arc shape centering on a rotation center of the rotating body when viewed from a rotation axis direction of the rotating body. The rotating body includes a gear tooth portion that can be engaged with the transmission gear, and a missing tooth portion that cannot be engaged with the transmission gear.
The housing includes a shaft portion that rotatably supports the rotating body,
One of the rotating body and the shaft portion is formed with an engagement piece configured to be flexibly deformable in the radial direction of the shaft portion, and the other is an engagement groove with which the engagement piece is engaged. Formed,
The developing cartridge according to claim 2, wherein the engagement piece and the engagement groove are engaged with each other in a state in which the toothless portion faces the transmission gear. The holding surface is formed in a planar shape,
The developing cartridge according to claim 1, wherein the holding member is configured to be linearly movable in a direction along the holding surface.

Images