JP4706713B2 - Developer cartridge - Google Patents

Description

  The present invention relates to a developing cartridge mounted on an image forming apparatus that detects a new article and a specification.

  In general, in an image forming apparatus such as a laser printer, a developing cartridge containing toner is detachably attached to the apparatus main body. As such an image forming apparatus, there has heretofore been known an apparatus capable of determining whether a mounted developing cartridge is new (detecting a new product) and determining the specifications of the developing cartridge (specification 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 and detecting a specification based on a signal from the sensor are provided. The developing cartridge mounted on the image forming apparatus includes one or two detection protrusions extending radially outward from a predetermined shaft portion, and a detection gear that rotates integrally with the detection protrusion about the shaft portion. A gear mechanism is provided that meshes with the detection gear and transmits a driving force to the developing roller.

  In this image forming apparatus, when the developing cartridge is mounted on the apparatus main body, the detection protrusion presses one end of the detection actuator, the detection actuator swings, and this swing is detected by the sensor. The signal detected by this sensor is transmitted to the control device as the first detection signal. When receiving the first detection signal, the control device determines that the developing cartridge is new.

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

  In such a glass turning operation, the transmission force from the driving source provided on the apparatus main body side is transmitted to the agitator and the detection gear on the developing cartridge side via the gear mechanism. As a result, the stirring of the toner by the agitator is started, and the detection protrusion 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. At this time, if there are two detection protrusions, the second detection protrusion again presses one end of the detection actuator, the detection actuator swings, and this swing is detected by the sensor. The signal detected by this sensor is transmitted to the control device as the second detection signal.

  When receiving the second detection signal, the control device determines that the specification of the developing cartridge is the A type (for example, the maximum image forming number is 6000 types). Note that if the second detection signal is not received, the control device determines that the specification of the developing cartridge is a type B different from the type A (for example, a type having a maximum image forming number of 3000).

JP 2006-267994 A

  By the way, the applicant of the present application has developed a method of performing specification detection by a method different from the above-described prior art. This method is a method of changing the timing at which the detection projection that presses the detection actuator when the developing cartridge is mounted retracts from the detection actuator by the loosening operation (the timing at which the detection actuator returns to the original position) according to specifications. Specifically, an engagement gear that rotates integrally with the detection protrusion and a rotating body that rotates coaxially with the engagement gear are provided, and these engaging gear and the rotating body are relatively rotatable in the initial state. However, when the rotating body rotates by a predetermined amount, the engaging portion of the rotating body engages with the engaged portion of the engaging gear, and these rotate integrally, so that the detection projection is rotated after the start of the rotation operation. The structure starts moving after a predetermined time. According to this, it is possible to detect the specification by the time difference from the start of the glass turning operation until the detection protrusion starts moving.

  However, in this structure, since two parts, that is, the rotating body and the engagement gear must be provided, there is a problem that the number of parts increases and the cost increases.

  Accordingly, an object of the present invention is to provide a developing cartridge capable of suppressing the number of parts in a structure in which the movement timing of the detection protrusion can be changed according to specifications.

In order to solve the above-described problems, a developing cartridge according to the present invention includes a housing for storing a developer and a detection protrusion formed so as to protrude from the housing so as to be able to come into contact with the detection actuator. And a rotation body that is rotatably provided on the housing and has the detection protrusion at a position deviated from the rotation center, and has a gear tooth portion and a tooth missing portion, and a driving force is applied to the gear tooth portion of the rotation body. A transmission gear for transmitting, and a contact portion of the detection projection with the detection actuator has a rotation center of the rotating body by each tip portion of a plurality of gear teeth arranged in a circumferential direction of the rotating body. It is characterized in that the distance from the center of rotation is constant by being configured in a circular arc shape with the center.

  According to the present invention, since the contact portion of the detection protrusion with the detection actuator is configured in an arc shape, the detection actuator contacts the arc-shaped contact portion even if the rotating body rotates due to the rotation operation. The sensing actuator does not move while Thereafter, when the arc-shaped contact portion is detached from the detection actuator, the support of the detection actuator by the contact portion is released, and the detection actuator swings and returns to the original position. In other words, according to the present invention, the detection actuator is returned from the start of the rattling operation only by changing the structure of one component (rotating body), more specifically, by changing the length of the arc-shaped contact portion of the detection protrusion. Thus, the number of parts can be reduced as compared with the structure in which the time difference is changed between two parts.

  According to the present invention, it is possible to freely change the time difference from the start of the glass turning operation to the return of the detection actuator only by changing the structure of one component (rotating body), so the time difference between the two components is changed. Compared to the structure, the number of parts can be reduced.

  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 briefly described, and then the details of the characteristic portions 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 casing 2 via the drum unit 51 or is detachably attached to the drum unit 51 fixed to the main 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, as the developing roller 31 rotates, the toner carried on the developing roller 31 is supplied to the electrostatic latent image formed on the surface of the photosensitive drum 27, 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.
As shown in FIGS. 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. The cover body 70 is detachably attached to the left side surface of the cartridge main body 60. As shown in FIG. 2A, a driving force is applied to the developing roller 31 and the like between the cartridge main body 60 and the cover body 70. A gear mechanism 61 for transmission and a rotating body 80 connected to the gear mechanism 61 (specifically, an agitator drive gear 66 to be described later) via a transmission gear 67 are provided. Here, the gear mechanism 61, the transmission gear 67, and the rotating body 80 are rotatably provided on the cartridge body 60 or the cover body 70.

  The gear mechanism 61 includes an input gear 62 to which a driving force is transmitted from a driving device 110 (see FIG. 4) 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.

  As shown in FIG. 3A, the rotating body 80 includes a ring-shaped middle plate portion 81 and an outer cylindrical portion 82 extending from the outer peripheral edge portion of the middle plate portion 81 to the inner side in the left-right direction (right side; cartridge main body 60 side). And an inner cylinder portion 83 extending inward in the left-right direction from the inner peripheral edge portion of the intermediate plate portion 81, and a detection protrusion 84 extending outward in the left-right direction (on the cover body 70 side) from the outer peripheral edge portion of the intermediate plate portion 81. Has been. Here, FIG. 3A is partially broken for convenience.

  As shown in FIG. 2, 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 outer cylinder portion 82. And the other part in which the gear tooth part 82A is not formed among the outer peripheral surfaces of the outer cylinder part 82 is a missing tooth part 82B that is not in contact with the transmission gear 67.

  As shown in FIG. 3A, the inner cylinder portion 83 is rotatably engaged with the outer peripheral surface of the support shaft portion 68 that protrudes outward from the cartridge body 60 in the left-right direction. The support shaft portion 68 is a shaft formed in a cylindrical shape, and a part of the support shaft portion 68 projects outward in the radial direction and is formed as a claw portion 68A that can be bent and deformed in the radial direction. The claw portion 68 </ b> A engages with the middle plate portion 81 of the rotator 80, thereby preventing the rotator 80 from coming off the support shaft portion 68.

  In addition, the inner cylinder portion 83 is formed with a pair of slits 83A that come out in a direction away from the middle plate portion 81, whereby the engagement pieces 83B that can be deformed in the radial direction between these slits 83A. Is formed. Further, as shown in FIG. 3B, an engagement protrusion 83C is formed at the tip of the engagement piece 83B so as to protrude radially inward. The engagement protrusion 83C is adapted to engage with a first engagement groove 68B and a second engagement groove 68C formed at the base of the support shaft portion 68 of the cartridge body 60. Thus, the position of the rotating body 80 is moved by the engagement between the engaging protrusion 83C and the first engaging groove 68B (or the second engaging groove 68C) until a predetermined force is applied to the rotating body 80 in the circumferential direction. To be maintained.

  The first engaging groove 68B is a groove that engages with the engaging protrusion 83C when the developing cartridge 28 is in a new state, and the second engaging groove 68C rotates the rotating body 80 by a predetermined amount by the rotation operation. This is a groove that engages with the engaging protrusion 83 </ b> C to maintain the missing tooth portion 82 </ b> B of the rotating body 80 in a direction facing the transmission gear 67. Further, the gear tooth portion 82A and the missing tooth portion 82B are formed at a predetermined ratio so that the relationship between the engagement protrusion 83C and the engagement grooves 68B and 68C is the above-described relationship.

  As shown in FIG. 3A, the detection protrusion 84 has a substantially C-shape, and in a state where the rotating body 80 is supported by the support shaft portion 68 of the cartridge body 60, the outer peripheral surface 84A thereof is The cover body 70 is arranged so as to protrude outward in the left-right direction so as to be able to come into contact with a detection arm 122 described later. Specifically, the detection protrusion 84 includes a half cylinder portion 84B formed in a C shape as an example of a contact portion, and a flange portion 84C extending radially inward from both circumferential ends of the half cylinder portion 84B. It is configured. The half cylinder portion 84 </ b> B is formed at a position shifted from the rotation center of the rotating body 80, and the outer peripheral surface 84 </ b> A is formed in a curved surface shape (arc shape) centering on the rotation center of the rotating body 80. . Here, the half cylinder part 84B is reinforced by the flange part 84C.

  As shown in FIG. 4, 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, there are a driving device 110 that transmits a driving force to the input gear 62 of the developing cartridge 28 and a new product specification detecting device 120 that can execute new product detection and specification detection. Is provided. In the present embodiment, a new (unused) developing cartridge refers to a cartridge in which the driving force is not yet applied to the input gear 62 and the developing roller 31 is not driven. Further, the old (used) developing cartridge refers to a cartridge in which a driving force has already been applied to the input gear 62 and the developing roller 31 has been driven.

  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. 5, 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 front end portion 122E of the contact arm 122C is disposed at a position where it can contact the detection protrusion 84 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 one 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 protrusion 84. 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, the operation of the rotating body 80 when the developing cartridge 28 is mounted on the main casing 2 will be described.

  As shown in FIG. 4, when a new developing cartridge 28 is mounted in the main casing 2, the detection protrusion 84 of the rotating body 80 is moved to the lower end portion of the detection arm 122 (see FIG. 6A). It abuts on the front end 122E) of the abutting arm 122C. Then, the detection arm 122 is pressed by the detection protrusion 84, and the lower end portion of the detection arm 122 moves to the back side together with the detection protrusion 84 (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. Is transmitted to the rotating body 80, and the rotating body 80 rotates clockwise. At this time, since the outer peripheral surface 84A of the detection protrusion 84 of the rotating body 80 is formed in an arc shape centering on the rotation center of the rotating body 80, the detection arm 122 is supported by the outer peripheral surface 84A of the detection protrusion 84. While continuing, it will not return to its 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.

  After that, as shown in FIG. 6C, when the opening of the detection protrusion 84 that is substantially C-shaped (the opening formed between the pair of flange portions 84 </ b> C) reaches the lower end of the detection arm 122, The support of the detection arm 122 by the detection protrusion 84 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. The reception time is detected by detecting the detection arm 122 by changing the initial position of the rotating body 80 to the position shown in FIG. 6A and the position shown in FIG. The time supported by the protrusions 84 can be changed according to the specifications.

  As described above, before the rotating body 80 rotates, as shown in FIG. 7A, the engaging protrusion 83 </ b> C formed on the inner cylinder portion 83 of the rotating body 80 is a support shaft of the cartridge body 60. The first engagement groove 68B formed at the base of the portion 68 is engaged. When a predetermined driving force is transmitted from the transmission gear 67 to the rotating body 80, the engagement protrusion 83C is deformed radially outward as shown in FIG. 7B, and the first engagement groove 68B is formed. It moves while slidably contacting the outer peripheral surface of the support shaft portion 68. Thereafter, as shown in FIG. 7C, the engaging protrusion 83C is engaged with the second engaging groove 68C. Thereby, the rotation of the rotating body 80 is reliably stopped at the position shown in FIG. 6C, 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.
By simply changing the initial position of one component (rotating body 80), the time difference from the start of the glass turning operation to the return of the detection arm 122 can be freely changed, so that the time difference between the two components is changed. In comparison, the number of parts can be reduced.

  Since the outer peripheral surface 84A of the detection projection 84 is formed in a curved surface shape, the outer peripheral surface 84A can smoothly slide relative to the detection arm 122 when the rotating body 80 rotates, and the generation of abnormal noise is suppressed. be able to.

  Since the engagement protrusion 83C engages with the second engagement groove 68C, the posture of the rotating body 80 is maintained with the missing tooth portion 82B facing the transmission gear 67. Therefore, the gear tooth portion 82A of the rotating body 80 is retained. In addition, the malfunction of the rotating body 80 due to the meshing of the transmission gear 67 again can be suppressed.

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 above embodiment, the initial position of the rotating body 80 is changed according to the specification, so that a time difference is given to the reception time of the ON signal from the optical sensor 121 (the timing at which the detection arm 122 returns). The present invention is not limited to this. For example, as shown in FIG. 8, by properly using a rotating body 840 having a detection projection 841 having a circumferential length different from that of the embodiment and a rotating body 80 according to the embodiment according to specifications, A time difference can be added to the reception time of the ON signal from the optical sensor 121.

  In the above-described embodiment, the outer peripheral surface 84A of the substantially semi-cylindrical detection protrusion 84 is used as the contact portion, but the present invention is not limited to this. For example, as shown in FIGS. 9A and 9B, the abutting portion that abuts on the detection arm 122 is formed in an arc shape with a predetermined interval in the circumferential direction of the rotating body 800 (the center of rotation of the rotating body 800 is You may comprise by each front-end | tip part 811 of the some gear teeth 810 arrange | positioned by the circular arc shape centered. Specifically, as shown in FIG. 9 (c), the rotating body 800 is formed in a cylindrical shape, and more than half of its outer peripheral surface is composed of a plurality of gear teeth 810, and the remaining portions are It is a missing tooth portion 820 recessed inward in the radial direction. 9A and 9C, the plurality of gear teeth 810 are illustrated as circular arcs connecting the respective tip portions 811. In this structure, the transmission gear 67 disposed between the agitator drive gear 66 and the rotating body 800 is disposed on the back side (the mounting direction leading side) of the rotating body 800. Specifically, the transmission gear 67 is disposed so that the engaging portion (meshing portion) of the transmission gear 67 with the rotating body 800 is located at substantially the same position as the lower end portion of the detection arm 122.

  In this structure, as shown in FIG. 10A, when the new developing cartridge is mounted, the gear teeth 810 of the rotating body 800 come into contact with the lower end portion of the detection arm 122, thereby detecting the detection arm 122. Swings. Thereby, the new article judgment similar to the above-mentioned embodiment is performed.

  Thereafter, when a known gear turning operation is started, the rotating body 800 rotates clockwise via the input gear 62, the intermediate gear 65, the agitator driving gear 66 and the transmission gear 67 as shown in FIG. To do. At this time, since the tip portions 811 (see FIG. 9B) of the plurality of gear teeth 810 of the rotating body 800 are arranged in an arc shape centering on the rotation center of the rotating body 800, the detection arm 122 is While being supported by each gear tooth 810, it does not return to its 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 missing tooth portion 820 of the rotating body 800 reaches the lower end portion of the detection arm 122, the support of the detection arm 122 by the gear teeth 810 is released, and the detection arm 122 is returned to the neutral position by the coil spring 123. At this time, the gear teeth 810 of the rotating body 800 are disengaged from the transmission gear 67 and the rotation of the rotating body 800 is stopped. Then, when the detection arm 122 returns to the neutral position in this way, transmission of the ON signal from the optical sensor 121 to the control device 124 is stopped, and the control device 124 performs the same specification determination as in the above embodiment. Therefore, even in this structure, the same effects as those of the above embodiment can be obtained.

  In the above embodiment, the engaging piece 83B having the engaging protrusion 83C is provided on the rotating body 80, and the engaging grooves 68B and 68C are provided on the support shaft portion 68. However, the present invention is not limited to this, and Conversely, an engagement groove may be provided in the rotating body, and an engagement piece may be provided in the support shaft portion.

  In the above 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.

  The number and layout of each gear in each 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 therebetween. Further, the rotating body 80 may be coupled to the intermediate gear 65 directly or via a predetermined number of gears.

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. They are the perspective view (a) which shows the state which looked at the rotary body from the left side, and sectional drawing (b) of the right side part 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 and a detection arm when a developing cartridge is mounted in a main body casing, and the state when a glass turning operation is started 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 protrusion of a rotary body was cancelled | released. Sectional view (a) showing the relationship between the engaging protrusion and the engaging groove before the rotating body rotates, and sectional view showing the relationship between the engaging protrusion and the engaging groove while the rotating body is rotating ( It is sectional drawing (c) which shows the relationship between b) and the engagement protrusion and engagement groove after a rotary body rotates predetermined amount. It is a side view which shows the modification which changed the length in the circumferential direction of the detection protrusion of a rotary body. It is the side view (a) which shows the modification which comprised the contact part with the arm for a detection with several gear teeth, the enlarged view (b) of X part of Fig.9 (a), and a perspective view (c). . It is a figure which shows the effect | action of the rotary body of FIG. 9, and is explanatory drawing (a) which shows the relationship between a rotary body when a developing cartridge is mounted in a main body casing, and a detection arm, and the state when a glass turning operation | movement is started FIG. 5B is an explanatory diagram showing the state where the detection arm is unsupported by the gear teeth of the rotating body. FIG.

Explanation of symbols

28 Developing Cartridge 60 Cartridge Main Body 61 Gear Mechanism 67 Transmission Gear 68 Support Shaft 68A Claw 68B First Engaging Groove 68C Second Engaging Groove 70 Cover Body 71 Opening 80 Rotating Body 81 Middle Plate Part 82 Outer Cylindrical Part 82A Gear Tooth part 82B Missing tooth part 83 Inner cylinder part 83A Slit 83B Engagement piece 83C Engagement protrusion 84 Detection protrusion 84A Outer peripheral surface 84B Half cylinder part 84C Flange part

Claims (4)

A housing for containing the developer;
A detection protrusion formed so as to protrude outward from the housing so as to be able to contact the detection actuator;
A rotating body provided rotatably on the housing, having the detection projection at a position shifted from the rotation center, and having a gear tooth portion and a missing tooth portion,
A transmission gear for transmitting a driving force to the gear tooth portion of the rotating body,
The contact portion of the detection protrusion with the detection actuator is configured in an arc shape centered on the rotation center of the rotating body by the respective tip portions of a plurality of gear teeth arranged in the circumferential direction of the rotating body. The developing cartridge is characterized in that the distance from the rotation center is constant.   The developing cartridge according to claim 1, wherein the contact portion is formed in a curved shape. 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,
Claim 1, wherein the toothless portion is such that the said engagement piece in a state facing the transmission gear and the engaging groove are engaged, the rotary member and the shaft portion is configured Alternatively, the developing cartridge according to claim 2 .   A housing for containing the developer;
  A detection protrusion formed so as to protrude outward from the housing so as to be able to contact the detection actuator;
  A rotating body that is rotatably provided on the housing, has the detection protrusion at a position shifted from the rotation center, and has a gear tooth portion and a missing tooth portion,
  A transmission gear for transmitting a driving force to the gear tooth portion of the rotating body,
  The contact portion of the detection protrusion with the detection actuator is configured in an arc shape with the rotation center of the rotating body as the center, so that the distance from the rotation center is constant,
  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, wherein the rotating body and the shaft portion are configured such that the engagement piece and the engagement groove are engaged in a state where the toothless portion faces the transmission gear.

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