JP5045712B2 - Developing cartridge and image forming apparatus - Google Patents

Description

  The present invention relates to a developing cartridge and an image forming apparatus.

  An electrophotographic image forming apparatus forms an image using a developing cartridge containing toner. And means for detecting whether or not the developing cartridge is a new developing cartridge when the developing cartridge is exchanged in order to manage the amount of use of the developing roller provided in the developing cartridge and to ensure good image quality. Is required. Further, there are development cartridges of a large capacity type containing a large amount of toner and a small capacity type containing a small amount of toner, and means for detecting these specifications is also required.

  As a conventional technique for detecting the state (new or old, type, etc.) of these developing cartridges, for example, as in Patent Document 1, whether the developing cartridge is new or old is determined based on whether or not the light irradiated to the developing cartridge is reflected. The technology to do is known.

  Further, as disclosed in Patent Document 2, a technology for determining whether a developing cartridge is new or old based on the presence or absence of contact between a protrusion provided on the developing cartridge and an actuator provided on a printer main body is known.

JP 2006-243073 A JP 2006-267994 A

However, in the configuration in which the state of the developing cartridge is optically determined as in Patent Document 1, if the portion that emits light or the portion that reflects is contaminated, there is a possibility that appropriate determination cannot be made.
Further, in the configuration in which the state of the developing cartridge is determined by mechanical contact as in Patent Document 2, there is a problem that the positioning accuracy of the developing cartridge in the image forming apparatus is required to be high.

  Therefore, an object of the present invention is to make it less susceptible to dimensional errors and disturbances when determining the state of a developing cartridge.

In order to achieve the above-described object, the present invention provides a developer cartridge that includes a developer accommodating portion that accommodates a developer and is detachable from the image forming apparatus main body, and is a conductor detected by the image forming apparatus main body. The detection member includes a first state indicating that the developing cartridge is new and a developing cartridge is an old product by a driving force from the image forming apparatus. The detection member is configured to have a second state different from the first state, and the detection member includes a first conductor piece and a second conductor piece rotated by a driving force input from the image forming apparatus main body. The first conductor piece and the second conductor piece are at least partially overlapped when viewed from one direction in the first state, and the driving force causes the first conductor piece and the second conductor piece to be overlapped with each other. phase To be moved, in the second state, the first conductor piece and the second conductor piece is characterized in that the overlapping state is different from the first state when viewed from the one direction.

According to another aspect of the present invention, there is provided a developer cartridge that includes a developer accommodating portion that accommodates a developer, and is detachable from the image forming apparatus main body. And the detection member includes a first state indicating that the developing cartridge is a new product and a first state indicating that the developing cartridge is an old product based on a driving force from the image forming apparatus. Are configured to be capable of taking different second states, and the detection member includes a first magnetic piece and a second magnetic piece that are rotated by a driving force input from the image forming apparatus main body. The first magnetic piece and the second magnetic piece overlap at least partially when viewed from one direction in the first state, and the driving force causes the first magnetic piece and the second magnetic piece to overlap each other. Move relatively It is, in the second state, the first magnetic piece and the second magnetic piece, characterized in that the overlapping state is different from the first state when viewed from the one direction.

  As described above, the detection member is made of a conductor or a magnetic material, and the detection member detects that the development cartridge is in the first state and the development cartridge is an old product by the driving force from the image forming apparatus. In the second state different from the first state, when the state of the detection member is detected by the main body of the image forming apparatus, an electromagnetic induction action is caused in the coil of the main body of the image forming apparatus, and the reactance of the coil changes. . Therefore, the state of the developing cartridge, for example, whether it is new or not can be detected by detecting the detection signal accompanying the change in the reactance of the coil in the image forming apparatus main body.

  In addition, the “state of the detection member” in the present invention means the position and shape of the detection member.

The present invention also provides an image forming apparatus corresponding to such a developing cartridge, the developing cartridge described above, a driving force output unit for applying a driving force to the developing cartridge, a closed circuit including a coil, and the closed circuit. said signal detecting means for detecting a current or voltage of the circuit, with a change in the reactance of the coil, the detection member in the developing cartridge on the basis of a change in the detection signal by the signal detecting means detects that the first state And determining means for determining which state is in the second state.

  Such an image forming apparatus has a closed circuit including a coil, and due to the state of the detection member of the developing cartridge, for example, due to a difference in position and shape, the electromagnetic induction action changes in this coil, and the reactance changes. The state of the developing cartridge can be detected based on the change in the detection signal accompanying the change in reactance.

  According to the developing cartridge and the image forming apparatus of the present invention, the state of the detection member changes to cause an electromagnetic induction action on the coil of the image forming apparatus main body. Therefore, the state of the developing cartridge can be detected based on the change in the detection signal accompanying the change in the reactance of the coil. Since the state of the detection member is detected using electromagnetic induction, there is an effect that the possibility of being affected by a dimensional error of the developing cartridge and the image forming apparatus and disturbance such as dust is low.

1 is a cross-sectional view illustrating a schematic configuration of a developing cartridge and an image forming apparatus according to a first embodiment. FIG. 4 is a diagram illustrating attachment / detachment of a developing cartridge to / from an image forming apparatus main body. FIG. 3 is a side view illustrating the configuration of the developing cartridge according to the first embodiment. FIG. 3 is a plan view illustrating the configuration of the developing cartridge according to the first embodiment. 2 is a diagram illustrating an equivalent circuit of a closed circuit provided in the image forming apparatus. FIG. FIG. 4 is a side view (a) showing a state in which a detection member for determining a new developer cartridge is operating, and a side view (b) showing a state after the operation. It is a graph which shows the change of the reactance of a coil in a 1st embodiment. 5A is a side view of a developing cartridge showing a modification of the first embodiment, and FIG. 5B is a graph showing a change in reactance. FIG. 6A is a side view for explaining the configuration of the developing cartridge according to the second embodiment, and FIG. FIG. 7A is a side view for explaining the configuration of the developing cartridge according to the third embodiment, and FIG. They are a side view (a) explaining the structure of the developing cartridge which concerns on 4th Embodiment, and the enlarged view (b) of a detection gear. They are a side view (a) and a sectional view (b) for explaining a configuration of a developing cartridge according to a fifth embodiment, and a side view (c) and a sectional view (d) showing a state after operation. It is the side view (a) explaining the structure of the developing cartridge which concerns on 6th Embodiment, and the side view (b) which shows the state after an action | operation. It is a graph which shows the reactance change of the coil at the time of the action | operation of the developing cartridge which concerns on 6th Embodiment. It is the side view (a) explaining the structure of the developing cartridge which concerns on 7th Embodiment, sectional drawing (b), and sectional drawing (c) which shows the state after an action | operation. It is a graph which shows the reactance change of the coil at the time of the action | operation of the developing cartridge which concerns on 7th Embodiment. It is the side view (a) explaining the structure of the developing cartridge which concerns on 8th Embodiment, sectional drawing (b), and sectional drawing (c) which shows the state after an action | operation. It is the side view (a) explaining the structure of the developing cartridge which concerns on 9th Embodiment, the side view (b), and the side view (c) which shows the state after an action | operation. It is a graph which shows the reactance change of the coil at the time of the action | operation of the developing cartridge which concerns on 9th Embodiment. FIG. 10 is an exploded perspective view for explaining the configuration of the detection gear of the developing cartridge according to the tenth embodiment, a perspective view of the first conductor piece viewed from the inside (b), and a side view showing a state before the developing cartridge is operated. It is a side view (d) which shows figure (c) and the state after an action | operation. It is the side view (a) explaining the structure of the developing cartridge which concerns on 11th Embodiment, sectional drawing (b), and the side view (c) which shows the state after an action | operation.

[First Embodiment]
Next, a first embodiment of the present invention will be described in detail with reference to the drawings as appropriate.
<Overall configuration of laser printer>
As shown in FIG. 1, a laser printer 1 as an example of an image forming apparatus includes an feeder 4 for feeding paper 3 into a main body casing 2 as an example of an image forming apparatus main body, and an image on the paper 3. An image forming unit 5 and the like for forming are provided.

  The feeder unit 4 includes a paper feed tray 6 that is detachably attached to the bottom of the main casing 2 and a paper pressing plate 7 provided in the paper feed tray 6. The feeder unit 4 includes various rollers 11 that carry the paper 3 and remove paper dust. 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 various rollers 11.

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

  As shown in FIG. 2, the process cartridge 17 is configured to be detachably attached to the main body casing 2 by appropriately opening a front cover 2 </ b> A provided on the front side of the main body casing 2. The process cartridge 17 is mainly composed of a developing cartridge 100 and a drum unit 30.

  The developing cartridge 100 is detachable from the main casing 2 while being attached to the drum unit 30. As shown in FIG. 1, the developing cartridge 100 mainly includes a developing roller 101, a layer thickness regulating blade 102, a supply roller 103, and a casing 104 as an example of a developer container.

  In the developing cartridge 100, the toner in the casing 104 is stirred by the agitator 105 and then supplied to the developing roller 101 by the supply roller 103. At this time, the toner is positively frictionally charged between the supply roller 103 and the developing roller 101. Is done. The toner supplied onto the developing roller 101 enters between the layer thickness regulating blade 102 and the developing roller 101 as the developing roller 101 rotates, and is further developed as a thin layer having a constant thickness while being frictionally charged. It is carried on the roller 101.

  The drum unit 30 mainly includes a photosensitive drum 31, a scorotron charger 32, and a transfer roller 33. In the drum unit 30, the surface of the photosensitive drum 31 is uniformly positively charged by the charger 32 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 rotation of the developing roller 101 causes the toner carried on the developing roller 101 to be supplied to the electrostatic latent image formed on the surface of the photosensitive drum 31, and the toner on the surface of the photosensitive drum 31. An image is formed. Thereafter, the sheet 3 is conveyed between the photosensitive drum 31 and the transfer roller 33, whereby the toner image carried on the surface of the photosensitive drum 31 is transferred onto the sheet 3.

  The fixing unit 18 includes a heating roller 41 and a pressure roller 42 that holds the paper 3 between the heating roller 41. In the fixing unit 18 configured as described above, the toner transferred onto the paper 3 is thermally fixed while the paper 3 passes between the heating roller 41 and the pressure roller 42. The sheet 3 thermally fixed by the fixing unit 18 is conveyed to a paper discharge roller 45 disposed on the downstream side of the fixing unit 18, and is sent out from the paper discharge roller 45 onto a paper discharge tray 46.

<Configuration to detect new development cartridge>
The developing cartridge 100 receives a driving force for operating each part from the image forming apparatus main body. Specifically, as shown in FIG. 2, the main body casing 2 is provided with an output coupling 51 provided with a driving force from the motor 52 on the side wall, and the side wall of the developing cartridge 100 corresponds to the output coupling 51. The input gear 110 is provided at a position to be operated. The input gear 110 is integrally formed with an input coupling 115 that can be engaged with the output coupling 51. Thereby, the input gear 110 receives the driving force from the output coupling 51 and is driven to rotate clockwise in FIG.

  On the side wall of the main body casing 2 is provided a control board 81 that constitutes a control means 80 as an example of a determination means, and slightly above the rotation center (see FIGS. 1 and 3) of the agitator 105 on the side wall of the developing cartridge 100. A coil 61 as an example of a sensor that detects the detection member is provided corresponding to the position of the shift. The coil 61 is connected to the control means 80, and the current flowing through the coil 61 is measured by an ammeter (not shown) as an example of the signal detection means, so that the developing cartridge 100 is unused as described later. Or an old product that has already been used.

  The coil 61 forms a closed circuit connected to the AC power source. If shown as an equivalent circuit, the coil 61 is a circuit in which the AC power source 63 is connected to a circuit in which an inductance L and a resistor R are connected in series as shown in FIG. By measuring the current flowing through the closed circuit, a change in reactance of the coil 61 can be detected. In measuring the current, the voltage may be measured directly, or the new or old of the developing cartridge 100 may be determined from the measured voltage value without measuring the current.

  The reactance of the coil 61 is smaller when the conductor is close to the coil 61 than when the conductor is not close because the magnetic flux of the coil 61 is weakened by the eddy current generated in the conductor. Therefore, the reactance of the coil 61 is changed by detecting the positional relationship such that the conductor is close to or away from the coil 61, and the change in the state of the conductor can be detected.

  As shown in FIG. 3, in addition to the input gear 110 described above, the developing roller gear 120, the supply roller gear 130, the intermediate gear 140, the agitator gear 150, and the detection gear 160 are provided on the left side surface of the developing cartridge 100. Each casing is rotatably provided. In the following description, unless otherwise specified, the members are made of an insulator and a non-magnetic material, for example, a resin.

The developing roller gear 120 is provided so as to rotate integrally coaxially with the developing roller 101 and meshes with the input gear 110.
The supply roller gear 130 is provided so as to rotate coaxially and integrally with the supply roller 103 (see FIG. 1), and meshes with the input gear 110.
The intermediate gear 140 meshes with both the input gear 110 and the agitator gear 150 and has a function of transmitting the rotation of the input gear 110 to the agitator gear 150.
The agitator gear 150 is an example of a first transmission member, and is provided so as to rotate integrally with the rotating shaft of the agitator 105.

  The detection gear 160 is an example of a first rotating member, and a gear tooth portion 161 as an example of an engaging portion that meshes with the agitator gear 150 at a part of the outer periphery, and on the same reference circle as the gear tooth portion 161. There are no gear teeth, and the agitator gear 150 has a non-engagement portion 162 as an example of a non-engagement portion that cannot be engaged. On a side surface of the detection gear 160, a conductor plate 170 as an example of a detection member is attached to a part of the circumferential direction by fitting or bonding.

  Each of these gears is covered with a resin gear cover (not shown) except for the portion that requires exposure, such as the input coupling 115, but when fixing the gear cover to the casing 104, a metal screw is not used. It is desirable to fix by adhesion, welding or fitting. This is because if a conductor such as metal is close to the coil 61, the detection of the detection member by the coil 61 may be affected.

  As shown in FIGS. 1 and 3, the casing 104 of the developing cartridge 100 is adjacent to the developing chamber 104A as an example of the first chamber in which the developing roller 101 is accommodated, the developing chamber 104A, and the agitator 105 is accommodated. A toner storage chamber 104B as an example of the second chamber is formed. The conductive plate 170 is provided in a range corresponding to the toner storage chamber 104B in the development chamber 104A and the toner storage chamber 104B when viewed from the axial direction of the development roller 101.

  As shown in FIG. 3, the above-described coil 61 is positioned on the upper front side of the agitator gear 150, and is disposed so that the conductor plate 170 overlaps with the movement locus accompanying the rotation of the detection gear 160 in a side view. .

  As shown in FIG. 4, the developing roller 101 provided in the developing cartridge 100 is provided with an electrical contact 108 for applying a developing bias voltage so as to protrude from the right side surface.

The control means 80 shown in FIG. 2 has a CPU, ROM, RAM, etc., and when the change in the current value (detection signal) from the ammeter provided in the closed circuit greatly changes beyond a predetermined threshold value. It is configured to determine that it is new. Specifically, in the case of a new product, since the conductor plate 170 passes in front of the coil 61, at this time, the reactance decreases (the current value increases), and the absolute value or the increase width of the current value is a predetermined threshold value. If it exceeds the threshold value, it is determined that it is a new product, and if it does not exceed a predetermined threshold value, it is determined that it is an old product.
The control unit 80 is also configured to perform known general printer controls such as transport control of the paper 3 and agitation of toner by the agitator 105.

  The new and old determination operations of the developing cartridge 100 in the laser printer 1 configured as described above will be described.

When the developing cartridge 100 is new, the conductor plate 170 is located above the rotation shaft of the detection gear 160 as shown in FIG. This position is defined as a first position (first state) of the conductor plate 170.
When the power is turned on or when the control unit 80 receives a print job, the control unit 80 performs a so-called glass turning operation in which the agitator 105 is rotated for a predetermined time and stirred, and at this time, from the output coupling 51 Driving force is transmitted to the input gear 110, and rotation is transmitted from the input gear 110 to the detection gear 160 via the intermediate gear 140 and the agitator gear 150 in the directions of the arrows shown in FIG. The detection gear 160 rotates counterclockwise as shown in FIG. 6A and rotates in the direction facing the coil 61 as shown in FIG. 6A, and then the missing tooth portion 162 is formed in the agitator gear 150 as shown in FIG. 6B. The drive force is not transmitted from the agitator gear 150 when it rotates to the direction facing the motor, and stops. The position of the conductor plate 170 shown in FIG. 6B is the second position (second state).

In this process, the reactance X of the coil 61 temporarily decreases as shown in FIG. 7 corresponding to the timing at which the conductor plate 170 faces the coil 61. Therefore, the current value detected at this time is temporarily When the current value is higher than a predetermined threshold, for example, the control means 80 determines that the product is new.
When it is determined that the developing cartridge 100 is new, the control unit 80 performs a predetermined operation such as resetting the stored counter for the number of printed sheets to zero.

  On the other hand, when the developing cartridge 100 is an old product, the detection gear 160 may have been rotated before, and the detection gear 160 faces the missing tooth portion 162 and the agitator gear 150 shown in FIG. It is a posture to do. Therefore, even if the developing cartridge 100 is rotated, the conductor plate 170 remains stopped at the second position, so that the current flowing in the closed circuit does not change, and the control means 80 causes the developing cartridge 100 to be old. It is determined that it is a product.

  As described above, according to the laser printer 1 of the present embodiment, whether or not the reactance X of the coil 61 is changed differs depending on whether or not the conductor plate 170 moves in accordance with the rotation operation, and flows to the closed circuit of the image forming apparatus. Since the presence or absence of a change in the current value is different, the control unit 80 can determine whether the developing cartridge 100 is new or old. In this case, since the electromagnetic induction action is used, it is difficult to be influenced by the dimensional error of each component of the laser printer 1 and the disturbance such as dust.

  Since the conductive plate 170 is provided in a range corresponding to the toner storage chamber 104B, the conductive plate 170 is separated by the coil 61 at a position away from the developing roller 101 that uses a conductor such as a metal as a shaft in order to apply a voltage. The movement of 170 can be detected, and the detection accuracy is hardly adversely affected. Generally, metal or conductive resin is used for the shaft of the developing roller 101 in order to receive a developing bias. Since the developing chamber 104A is also provided with a supply roller 103 having a metal shaft and a metal layer thickness regulating blade 102, according to this configuration, the conductor plate formed by the coil 61 at a position away from these members. The movement of 170 can be detected.

  The electrical contact 108 for applying a voltage to the developing roller 101 is provided on the side surface opposite to the conductor plate 170 of the developing cartridge 100. That is, since the conductor plate 170 and the electrical contact 108 are separated from each other, it is difficult to affect the detection of the movement of the conductor plate 170 by the coil 61.

  Further, since the input coupling 115 for inputting driving force to the developing roller 101 is disposed on the same side as the side surface on which the conductive plate 170 is provided on the side surface of the developing cartridge 100, the conductive plate 170 is operated. The power transmission path to be made can be shortened, and the power transmission mechanism can be made compact.

  In the first embodiment described above, the conductor plate 170 is disposed so as to overlap the coil 61 in the side view as the movement locus associated with the rotation of the detection gear 160, but this is not essential, and detection by the coil 61 is possible. As long as the movement locus of the conductor plate 170 is slightly different from the position of the coil 61,

  In the first embodiment, only the new and old of the developing cartridge 100 are determined. However, as shown in FIG. 8A, the conductor plate 170 is placed on the same circumference on the detection gear 160. Two of them may be used. In this case, as shown in FIG. 8B, since the reactance X is lowered twice during the determination operation, it can be detected that two conductor plates 170 are provided. Therefore, if two types of developing cartridges 100, one having one conductor plate 170 arranged as shown in FIG. 3 and two arranged as shown in FIG. Differences in specifications of 100 types, for example, whether the amount of toner contained therein is large or small, can be determined.

  In the first embodiment, the detection member is a plate-shaped conductor plate 170. However, as long as the detection member has a size that can detect a change in reactance of the coil 61, the detection member may have another shape such as a columnar shape. It does not matter. And as a detection member, not only what consists of conductors but a magnetic body and what is a magnetic body and is a conductor can be used. When a magnetic material is used for the detection member, the reactance X increases because the magnetic flux of the coil 61 is increased when approaching the coil 61, unlike the case of the conductor. Also, when a magnetic material and a conductor are used for the detection member, the reactance X changes according to the frequency of the alternating current applied to the closed circuit. In any of these cases, the state of the developing cartridge 100 can be detected by the change in the reactance X.

  Hereinafter, other embodiments of the present invention will be sequentially described. In the following embodiments, only portions different from the first embodiment will be described, and portions similar to those of the first embodiment will be denoted by the same reference numerals and description thereof will be omitted. In each embodiment, a case where a conductor is used as the detection member will be described. However, a magnetic body or a conductor and a magnetic body can be used instead of the conductor.

[Second Embodiment]
As shown in FIG. 9A, the developing cartridge 200 of the second embodiment employs a friction wheel 260 that does not use gear teeth instead of the detection gear 160 of the first embodiment. The friction wheel 260 can be rotated by a frictional force received from the agitator gear 150 by winding a rubber ring 262 around the outer periphery of the D-shaped main body 261 in a side view.
Of the outer periphery of the D-shaped friction wheel 260, a circumferential portion 260A having a circumferential shape is an engaging portion, and a straight portion 260B is a non-engaging portion. The friction wheel 260 is in the posture of being engaged with the agitator gear 150 at the leftmost end in FIG. 9A, that is, at the beginning of the engagement with the agitator gear 150 in the circumferential portion 260 </ b> A.
The friction wheel 260 is provided with a conductor plate 270 at the same position as in the first embodiment.

  According to such a developing cartridge 200, when a rotational driving force is input from the output coupling 51 of the image forming apparatus main body to the input coupling 115 of the developing cartridge 200 in a new state shown in FIG. The rotation is transmitted to the friction wheel 260 via the input gear 110, the intermediate gear 140 and the agitator gear 150. Then, as shown in FIG. 9B, the friction wheel 260 stops when the straight portion 260 </ b> B comes into a posture facing the agitator gear 150. During this time, since the conductor plate 270 passes in front of the coil 61, the reactance X of the coil 61 changes as in the first embodiment. When this change occurs, it can be determined that the developing cartridge 200 is new, and when there is no change, it can be determined that it is an old product.

[Third Embodiment]
As shown in FIG. 10, the developing cartridge 300 according to the third embodiment uses a belt for transmitting a driving force for driving the detection member.
In the developing cartridge 300, the agitator gear 350 has a pulley 351 coaxially and integrally, and a pulley 352 is provided in front of the pulley 351. A belt 353 is wound between the pulley 351 and the pulley 352.
Above the belt 353, a D-shaped friction wheel 360 having a circumferential portion 360A (engagement portion) and a straight portion 360B (non-engagement portion) in a side view is provided. The friction wheel 360 is pressed against the belt 353 from above at the head of the circumferential portion 360A in the counterclockwise direction (near the lower end of FIG. 10A).
The friction wheel 360 is provided with a conductor plate 370 at the same position as in the first embodiment.

  According to such a developing cartridge 300, when a rotational driving force is input from the output coupling 51 of the image forming apparatus main body to the input coupling 115 of the developing cartridge 200 in a new state shown in FIG. The rotation is transmitted to the belt 353 through the input gear 110, the intermediate gear 140, the agitator gear 350 and the pulley 351. The rotation of the belt 353 is transmitted to the friction wheel 360 by a frictional force. Then, as shown in FIG. 10B, the friction wheel 360 stops when the straight portion 360 </ b> B is in a posture facing the belt 353. During this time, since the conductor plate 370 passes in front of the coil 61, the reactance X of the coil 61 changes in the same manner as in the first embodiment. When this change occurs, it can be determined that the developing cartridge 400 is new, and when there is no change, it can be determined that it is an old product.

[Fourth Embodiment]
As shown in FIG. 11A, the developing cartridge 400 according to the fourth embodiment uses a coil 470 as a detection member. The coil 470 is a conductor and is a closed circuit in which the ends of the coil 470 are connected to each other as shown in an enlarged view in FIG. The coil 470 is provided on the side surface of the detection gear 460 by printing or transfer. Similar to the detection gear 160 of the first embodiment, the detection gear 460 has a gear tooth portion 461 and a missing tooth portion 462.

  Also with such a developing cartridge 400, it is possible to determine whether the developing cartridge 400 is a new product or an old product based on a change in the reactance X of the coil 61, as in the first embodiment. When the coil 470 is used, the influence on the coil 61 can be changed by adjusting the number of turns. Therefore, the coil 61 can be changed by changing the number of turns according to the difference in specifications such as the toner capacity. It is possible to make a difference in the amount of change in the reactance X measured in step (1), and the specification of the developing cartridge 400 can be detected by the coil 61.

[Fifth Embodiment]
As shown in FIG. 12, the developing cartridge 500 of the fifth embodiment is provided not on a member that rotates the detection member but on a member that slides.
In the developing cartridge 500, the agitator gear 550 has a pinion gear 551 as an example of a second transmission member coaxially and integrally. In front of the pinion gear 551, a rack gear 560 is provided as an example of a slide member that extends straight forward and upward. The rack gear 560 is engaged with the guide 568 and guided in the moving direction. The rack gear 560 has a gear tooth portion 561 (engagement portion) that can mesh with the pinion gear 551 and a missing tooth portion 562 (non-engagement portion) without gear teeth on one plane along the slide direction. The rack gear 560 overlaps with the coil 61 in a side view, and a conductor plate 570 is provided in a portion located above the coil 61.

  According to such a developing cartridge 500, when a rotational driving force is input from the output coupling 51 of the image forming apparatus main body to the input coupling 115 of the developing cartridge 200 in the new state shown in FIG. Driving force is transmitted to rack gear 560 through input gear 110, intermediate gear 140, agitator gear 550 and pinion gear 551. The rack gear 560 slides downward along the guide 568 and stops when the missing tooth portion 562 reaches a position facing the pinion gear 551 as shown in FIG. During this time, since the conductor plate 570 passes in front of the coil 61, the reactance X of the coil 61 changes as in the first embodiment. When this change occurs, it can be determined that the developing cartridge 500 is new, and when there is no change, it can be determined that it is an old product.

[Sixth Embodiment]
In the developing cartridge 600 of the sixth embodiment shown in FIGS. 13A and 13B, the detection member does not move in a side view of the developing cartridge, but moves in the axial direction of the developing roller 101.
The developing cartridge 600 has a lower step 604 that is one step lower on the side wall, and a cover gear 660 that engages with the agitator gear 150 meshes with the lower step 604. The cover gear 660 includes a gear portion 661 and a cover portion 662 as an example of a locking member that protrudes only partially in the circumferential direction around the gear portion 661, and these cover portions have a predetermined upper limit by a torque limiter (not shown). It is connected so that torque can be transmitted by torque.

  A hole 672 having a circular cross section is provided at a position corresponding to the coil 61 on the side wall of the lower step 604, and a cylindrical conductor piece 670 is disposed in the hole 672. The conductor piece 670 is biased to the outside by a spring 678 disposed at the bottom of the hole 672, but in the new state shown in FIGS. 13A and 13B, the outer end portion is the cover portion 662. It is stopped by jumping out by being pressed by. The position of the cover part 662 at this time is a locking position. A flange 671 is provided at the innermost end of the conductor piece 670. Even when the engagement with the cover portion 662 is released, the flange 671 is caught on the edge of the opening of the hole portion 672, thereby the conductor piece 670. Is prevented from falling off the casing 104 completely.

  In such a developing cartridge 600, when the driving force from the image forming apparatus main body is transmitted to the agitator gear 150, and the rotation of the agitator gear 150 is transmitted to the cover gear 660, the cover portion 662 rotates, and the cover portion 662 and the conductor piece. 670 is disengaged. Then, the conductor piece 670 jumps out by the urging force of the spring 678. When the agitator gear 150 continues to rotate, the cover 662 is caught by the protruding conductor piece 670, so that the cover 662 is stopped and the torque limiter between the cover 662 and the gear 661 continues to slide. The position of the cover part 662 at this time is an open position.

  By such an operation, the conductor piece 670 moves suddenly from the first position (first state) far from the coil 61 to the second position (second state) close to the coil 61, so that as shown in FIG. The reactance X decreases rapidly when the conductor piece 670 moves. Therefore, the control unit 80 can detect that the developing cartridge 600 is new by detecting the change in the current value accompanying the change in the reactance X, and can determine that the developing cartridge 600 is old if there is no change.

[Seventh Embodiment]
The developing cartridge 700 of the seventh embodiment shown in FIG. 15 is an example showing another form in which the conductor moves in the axial direction of the developing roller 101. As shown in FIGS. 15A and 15B, the developing cartridge 700 has a lower step 704 that is one step lower on the side wall, and a left-handed stud bolt 760 (male screw) is fixed to the lower step 704. Yes. A detection gear 770 as an example of a second rotating member made of a conductor such as metal is screwed to the stud bolt 760. The developer cartridge 700 is engaged with the agitator gear 150 in a new state as shown in FIG.

  In such a developing cartridge 700, when the driving force from the image forming apparatus main body is transmitted to the agitator gear 150 and the rotation of the agitator gear 150 is transmitted to the detection gear 770, the detection gear 770 is counterclockwise in FIG. It rotates and gradually moves on the stud bolt 760 toward the lower step portion 704. Then, as shown in FIG. 15C, when the engagement between the agitator gear 150 and the detection gear 770 is disengaged, the rotation of the detection gear 770 is stopped and the movement is stopped.

By such an operation, the detection gear 770 gradually moves from the first position close to the coil 61 (first state) to the second position far away from the coil 61 (second state). Therefore, as shown in FIG. The reactance X gradually increases as the detection gear 770 moves. Therefore, the control unit 80 can determine that the developing cartridge 700 is new by detecting the change in the current value accompanying the change in the reactance X, and can determine that the developing cartridge 700 is old if there is no change.
In this embodiment, the detection gear 770 rotates around the stud bolt 760. However, the relationship between the male screw and the female screw may be reversed, and only a part of the detection gear 770, not the whole, is a conductor. There may be.

[Eighth Embodiment]
The developing cartridge 800 of the eighth embodiment shown in FIG. 17 is an example showing still another form in which the conductor moves in the axial direction of the developing roller 101. As shown in FIGS. 17A and 17B, a developing cartridge 800 has a screw shaft 863 having a left-hand thread rotatably supported on a side wall, and a gear 862 is provided on the outer side of the screw shaft 863 with a screw shaft 863 ( It is provided integrally with the male screw). The gear 862 meshes with the intermediate gear 861, and the intermediate gear 861 meshes with the agitator gear 150.

  On the side wall of the developing cartridge 800, a hole 872 having a rectangular cross section is formed coaxially with the screw shaft 863. A conductor piece 870 as an example of a moving member having an outline corresponding to the rectangular cross section of the hole 872 and having a female screw threadedly engaged with the screw shaft 863 is formed in the hole 872 near the opening end of the hole 872. It is arranged in a state of being fitted into the portion 872. Of the screw shaft 863 in the hole portion 872, a predetermined range on the back side of the hole portion 872 is a shaft portion 863A in which a screw is not cut. The length of the shaft portion 863A is larger than the thickness of the engaged conductor piece 870 (the size of the screw shaft 863 in the axial direction). In the new state of the developing cartridge 800, the conductor piece 870 is located in the vicinity of the opening end of the hole portion 872, as shown in FIG.

  In such a developing cartridge 800, when the driving force from the image forming apparatus main body is transmitted to the agitator gear 150 and the rotation of the agitator gear 150 is transmitted to the gear 862, the gear 862 rotates clockwise in FIG. The conductor piece 870 gradually moves along the screw shaft 863 toward the back of the hole portion 872. As shown in FIG. 17C, when the conductor piece 870 moves to the shaft portion 863A of the screw shaft 863, the conductor piece 870 does not move.

  By such an operation, the conductor piece 870 gradually moves from the first position close to the coil 61 (first state) to the second position far away from the coil 61 (second state). Therefore, as in the seventh embodiment, the coil 61 This reactance X gradually increases as the detection gear 770 moves. Therefore, the control unit 80 can determine that the developing cartridge 800 is new by detecting a change in the current value accompanying the change in the reactance X, and can determine that the developing cartridge 800 is an old product if there is no change. In this embodiment, the screw shaft 863 rotates with respect to the conductor piece 870. However, the relationship between the male screw and the female screw may be reversed, and only a part of the conductor piece 870, not the whole, is a conductor. May be.

[Ninth Embodiment]
The developing cartridge 900 of the ninth embodiment shown in FIG. 18 shows another form in which the driving force from the image forming apparatus main body is not transmitted to the detection member. That is, in the power transmission path where the driving force is transmitted to the detection member, the engagement for power transmission is disengaged during the power transmission operation. As shown in FIG. 18A, in the developing cartridge 900, a rotating plate 960 is rotatably provided at a position on the side wall where the detection gear 160 of the first embodiment is provided. The agitator gear 150 is provided with a pin 981, and one end of the rod 980 is rotatably engaged with the agitator gear 150 via the pin 981. The other end of the rod 980 has a groove 982 opened at the end in the longitudinal direction, and this groove 982 is engaged with a pin 961 provided on the rotating plate 960.

  The rotating plate 960 is provided with a conductor plate 970 at a part in the circumferential direction. When the developing cartridge 900 is new, the conductor plate 970 is disposed at a position closest to the coil 61, and the pin 981 is connected to the agitator gear 150. It is located slightly rearward and upward with respect to the rotation axis. Further, below the rotating plate 960, a receiving base 990 that receives the rod 980 that is disengaged from the pin 961 is provided.

  In such a developing cartridge 900, when the driving force from the image forming apparatus main body is transmitted to the agitator gear 150 and the rotation of the agitator gear 150 pushes the rod 980 forward, the rod 980 is moved as shown in FIG. When the other end pushes the pin 961, the rotating plate 960 is rotated clockwise in the figure. After the pin 961 is positioned farthest from the agitator gear 150, the rod 980 moves rearward as shown in FIG. 18C, and the pin 961 is removed from the groove 982, and the rod 980 is moved to the cradle 990. fall into. Therefore, after this, the rotating plate 960 does not rotate.

  By such an operation, the conductor plate 970 suddenly moves away from the first position (first state) close to the coil 61 to the second position (second state) far from the coil 61. Therefore, as shown in FIG. X increases rapidly as the conductor plate 970 moves. Therefore, the control unit 80 can detect that the developing cartridge 900 is new by detecting the change in the current value accompanying the change in the reactance X, and can determine that the developing cartridge 900 is old if there is no change.

[Tenth embodiment]
The developing cartridge A of the tenth embodiment shown in FIG. 20 is an example in which the shape of the conductor changes due to the driving force from the image forming apparatus main body.
As shown in FIGS. 20A and 20B, the detection gear A70 used in the developing cartridge A is rotatably supported on the side wall of the developing cartridge A, and has a first conductor piece A71 having gear teeth A72 on the outer periphery. The second conductor piece A75 having no gear teeth is provided on the outer periphery that is rotatably supported relative to the first conductor piece A71. The first conductor piece A71 has a semicircular opening A73, and an engagement piece A74 that protrudes inward in the left-right direction of the developing cartridge A is formed. The gear teeth A72 of the first conductor piece A71 mesh with the agitator gear 150.
The second conductor piece A75 also has a semicircular opening A76, and an engagement piece A77 that protrudes outward in the left-right direction of the developing cartridge A is formed.

  In a new state of the developing cartridge A, the opening A73 and the opening A76 are arranged so as to overlap each other, and the conductor portions on the opposite side of the opening A73 and the opening A76 are also arranged so as to overlap each other. The opening A73 and the opening A76 are disposed at positions facing the coil 61. Further, as shown in FIG. 20 (c), the engagement piece A74 and the engagement piece A77 are on opposite sides (positions shifted by 180 °) across the rotation centers of the first conductor piece A71 and the second conductor piece A75. Has been placed. This state of the detection gear A70 is the first state.

  In such a developing cartridge A, when the driving force from the image forming apparatus main body is transmitted to the agitator gear 150 and the rotation of the agitator gear 150 is transmitted to the first conductor piece A71, the first 180 ° is only the first conductor piece A71. After the engagement piece A74 and the engagement piece A77 are engaged, the first conductor piece A71 and the second conductor piece A75 continue to rotate together. The state in which the first conductor piece A71 and the second conductor piece A75 are integrated is the second state. In the second state, the conductor piece B70 includes the first conductor piece A71 and the second conductor piece A75 that are continuous on a circle having a predetermined radius around the rotation center as viewed from one direction (in a side view). It can be said.

  By such an operation, the opening A73 and the opening A76 are opposed to the coil 61 at the beginning when the developing cartridge A is new, but the rotation of the detection gear A70 causes the detection gear A70 to move as shown in FIG. The reactance X of the coil 61 decreases rapidly from when the conductor portion faces the coil 61. Therefore, the control unit 80 can determine that the developing cartridge A is new by detecting a change in the current value accompanying the change in the reactance X, and can determine that the developing cartridge A is an old product if there is no change.

[Eleventh embodiment]
The developing cartridge B of the eleventh embodiment shown in FIG. 21 is configured such that the driving force from the image forming apparatus continues to be transmitted to the detection member, but the position of the detection member is stopped by a torque limiter. That is, it is a form provided with the latching member which stops a detection member in a 2nd position, and the torque limiter provided in the power transmission path | route which a driving force transmits to a detection member.

  As shown in FIGS. 21A and 21B, the developing cartridge B is provided with a gear B60 that meshes with the agitator gear 150 at the same position as the detection gear 160 of the first embodiment. A collar B71 is provided that is fitted to the outside of the shaft B61 so as to generate a predetermined frictional force between the gear B60 and the shaft B61 that rotates together with the gear B60. That is, between the shaft B61 and the collar B71, torque is transmitted with a predetermined upper limit torque, and these constitute a torque limiter. In the collar B71, a conductor piece B70 is formed so as to protrude in the radial direction at a part in the circumferential direction.

  The conductor piece B70 has a size capable of facing the coil 61 and protrudes outward in the radial direction of the collar B71. When the developing cartridge B is new, as shown in FIG. positioned. This is the first position of the conductor piece B70. A stopper B80 is provided in front of and below the shaft B61 at a position where it can engage with the rotating conductor piece B70. The stopper B80 is fixed to the side wall of the developing cartridge B.

  When the driving force from the image forming apparatus main body is transmitted to the agitator gear 150 and the rotation of the agitator gear 150 is transmitted to the gear B60, the developing cartridge B rotates with the shaft B61 and the collar B71 being integrated with each other. The conductor piece B70 also rotates counterclockwise in FIG. Then, as shown in FIG. 21C, when the conductor piece B70 comes into contact with the stopper B80, the rotation of the conductor piece B70 is stopped and continues to slide between the shaft B61 and the collar B71. This state is the second position of the conductor piece B70.

  By such an operation, when the developing cartridge B is new, the conductor piece B70 passes in front of the coil 61, and the reactance X of the coil 61 is temporarily reduced as shown in FIG. Therefore, the control unit 80 can detect that the developing cartridge B is new by detecting a change in the current value accompanying the change in the reactance X, and can determine that the developing cartridge B is an old product if there is no change.

  As exemplified in the above embodiments, according to the present invention, the coil 61 detects that the conductor or the magnetic body changes from the first state (first position) to the second state (second position). It is possible to detect the state of the development cartridge, such as the old and new, and the specifications. Since this detection uses the action of electromagnetic induction, the dimensional accuracy of each part of the laser printer 1 is not required to be high and is not easily affected by dust, so that stable determination is possible.

Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and can be implemented with appropriate modifications.
For example, only a monochrome printer is illustrated as an image forming apparatus, but the present invention can also be applied to a color printer, a multifunction peripheral, a copier, and the like.
Further, the developing cartridge may be provided with a conductor or a magnetic body whose position or the like does not change, separately from the above-described conductor or magnetic body that acts greatly on the coil 61.

  Hereinafter, the rotating body such as the gear described in the above embodiment will be further defined.

  The present invention includes a rotating body main body made of a material other than a conductor and a magnetic body, a conductor provided in a part of the rotating body main body in a circumferential direction, and a power input unit to which rotational driving force is input. It can be provided as a rotating body used in the developing cartridge, such as a gear, a friction wheel, or a pulley.

  The present invention also includes a rotating body main body made of a material other than a conductor and a magnetic body, a magnetic body provided in a part of the rotating body main body in a circumferential direction, and a power input unit to which rotational driving force is input. It can be provided as a rotating body, such as a gear, a friction wheel, a pulley, etc., used in a developing cartridge.

DESCRIPTION OF SYMBOLS 1 Laser printer 2 Main body casing 2A Front cover 3 Paper 51 Output coupling 52 Motor 61 Coil 80 Control means 81 Control board 100 Developing cartridge 101 Developing roller 104 Casing 104A Developing chamber 104B Toner storage chamber 105 Agitator 108 Electric contact 110 Input gear 115 Input Coupling 120 Developing roller gear 130 Supply roller gear 140 Intermediate gear 150 Agitator gear 160 Detection gear 161 Gear tooth portion 162 Missing tooth portion 170 Conductor plate

Claims (6)

A developer cartridge that includes a developer accommodating portion that accommodates a developer and is detachable from the image forming apparatus main body,
A detection member made of a conductor detected by the image forming apparatus main body;
The detection member is different from a first state in which the developing cartridge is a new product and a first state in which the developing cartridge is an old product by a driving force from the image forming apparatus. Configured to take two states ,
The detection member has a first conductor piece and a second conductor piece rotated by a driving force input from the image forming apparatus main body,
The first conductor piece and the second conductor piece are at least partially overlapped when viewed from one direction in the first state, and the first conductor piece and the second conductor piece are relative to each other by the driving force. Moved,
The developing cartridge according to claim 2, wherein the first conductor piece and the second conductor piece are different from each other in the overlapping state when viewed from one direction . A developer cartridge that includes a developer accommodating portion that accommodates a developer and is detachable from the image forming apparatus main body,
Having a detection member made of a magnetic material detected by the image forming apparatus main body;
The detection member is different from a first state in which the developing cartridge is a new product and a first state in which the developing cartridge is an old product by a driving force from the image forming apparatus. Configured to take two states ,
The detection member includes a first magnetic piece and a second magnetic piece rotated by a driving force input from the image forming apparatus main body.
The first magnetic piece and the second magnetic piece overlap at least partially when viewed from one direction in the first state, and the first magnetic piece and the second magnetic piece are driven by the driving force. The pieces are moved relative to each other,
The developing cartridge according to claim 2, wherein in the second state, the first magnetic piece and the second magnetic piece are different in overlapping state from the first state when viewed from one direction . A developing roller for carrying the developer accommodated in the developer accommodating portion;
The developer accommodating portion has a first chamber in which the developing roller is accommodated, and a second chamber in which a member for agitating the developer adjacent to the first chamber is accommodated.
The developing cartridge according to claim 1, wherein the detection member is provided corresponding to a range in which the second chamber is formed when viewed from the axial direction of the developing roller. A developing roller for carrying the developer accommodated in the developer accommodating portion;
An electrical contact for applying a voltage to the developing roller is provided on one side surface of the developer container,
The developing cartridge according to claim 1, wherein the detection member is provided on the other side surface of the developer accommodating portion. A developing roller for carrying the developer accommodated in the developer accommodating portion;
A driving force input portion for inputting driving force to the developing roller is provided on a side surface of the developer accommodating portion,
The developing cartridge according to claim 1, wherein the detection member is provided on a side surface on the drive input unit side. A developing cartridge according to claim 1 or 2,
A driving force output unit for applying a driving force to the developing cartridge;
A closed circuit including a coil;
Signal detection means for detecting the current or voltage of the closed circuit;
Due to the change of the reactance of the coil, determining means for determining the signal detection means the detection member in the developing cartridge on the basis of a change in the detection signal detected is in either of said second state and said first state An image forming apparatus comprising:

Images