JP2009145912A - Image forming apparatus and developer cartridge - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image forming apparatus capable of determining information on a developer cartridge, while preventing a rise in costs and avoiding an increase in structural complexity, and to provide a developer cartridge detachably mounted in the image forming apparatus. <P>SOLUTION: When the developer cartridge 30 is mounted in a body casing 2, a sensor gear 70 is driven one-half of a rotation by a motor 59. Contact protrusions 82 are moved in a circumferential direction together with the rotation of the sensor gear 70 to pass through a detection position of an actuator 91. An optical sensor 92 detects passage of the contact protrusion 82. A CPU 90 determines the information on the developer cartridge 30 on the basis of whether the optical sensor 92 has detected the contact protrusion 82. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an image forming apparatus such as a laser printer, and a developing cartridge that is detachably attached to the image forming apparatus.

Conventionally, a developing cartridge containing toner is detachably attached to a laser printer. Such a laser printer is provided with a new article detecting means for detecting whether or not the installed developing cartridge is new and determining the life of the developing cartridge from the detection of the new article.
For example, when a developing device is provided with a sector gear having recesses and protrusions and a new developing device is mounted on an electrophotographic image forming apparatus main body, the protrusion formed on the sector gear is detected as a new-side detection sensor. When the idler gear starts to be driven after the development device is mounted after the new product side detection sensor is turned on, the sector gear also rotates, and the protrusion moves from the new product side detection sensor to the old product side detection sensor. It has been proposed that the protrusion enters the old product side detection sensor and turns on the old product side detection sensor, and at the same time, the idler gear reaches the concave portion of the sector gear to stop the rotation of the sector gear (for example, , See Patent Document 1).

Japanese Patent Laid-Open No. 2000-221781

However, in the new article detection means described in Patent Document 1, when the new article is detected, the protrusion enters the new article side detection sensor, and when the old article is detected, the projection enters the old article side detection sensor. The old product side detection sensor is necessarily required, which increases the cost and makes the apparatus configuration complicated.
In addition, when replacing the developer cartridge, it is desired to select an optimum developer cartridge from a plurality of developer cartridges having different price ranges according to the amount of toner contained, taking into consideration the frequency of use and cost. There is a request from the user.

In order to meet this demand, when developing cartridges having different amounts of toner contained therein are prepared, the degree of agitation varies depending on the amount of toner contained, and the toner deterioration rate also differs.
In such a case, even if it is detected that the cartridge is new, if the amount of stored toner varies depending on the developing cartridge, the lifetime of the developing cartridge from the detection of the new cartridge will be different. An accurate determination cannot be made. For this reason, in a developing cartridge that contains a small amount of toner, even if the end of the life is actually reached, the life is not determined and the image may be deteriorated.

  SUMMARY OF THE INVENTION An object of the present invention is an image forming apparatus capable of determining information relating to a developing cartridge while suppressing an increase in cost and avoiding the complexity of the apparatus configuration, and is detachably attached to the image forming apparatus. It is to provide a developing cartridge.

  In order to achieve the above object, an invention according to claim 1 is directed to an image forming apparatus main body, a developing cartridge that is detachable from the image forming apparatus main body and contains a developer, and the image forming apparatus main body. And a driving unit provided in the developing cartridge, and when the developing cartridge is mounted on the image forming apparatus main body, the driving unit can drive the driving unit, and a predetermined driving amount from a driving start to a driving stop is provided. A driving member to be driven, a moving member movable along with the driving of the driving member, a detecting means capable of passing the moving member moving by driving of the driving member, and detecting the passage of the moving member; Information determining means for determining information relating to the developing cartridge based on the detection result of the moving member by the detecting means. It is characterized.

  According to such a configuration, when the developing cartridge is mounted in the image forming apparatus main body, the driving member is driven by a predetermined driving amount from the driving start to the driving stop by the driving unit. Then, when the drive member is driven, the moving member moves and passes through the detecting means, and the detecting means detects the passage of the moving member. Then, the information determination unit determines information related to the developing cartridge based on the detection result of the moving member by the detection unit. Therefore, it is possible to determine information related to the developing cartridge with a simple configuration while reducing costs.

Moreover, in such a structure, since a detection means passes a moving member and detects the passage, a plurality of moving members can be provided and a plurality of moving members can be passed through the detecting means. As a result, the information determination unit can determine information related to the plurality of developing cartridges based on detection of the plurality of moving members by the detection unit.
According to a second aspect of the present invention, in the first aspect of the present invention, the detection unit includes a contact member that contacts the moving member, and the moving member contacts the contact member. The direction and the moving direction of the moving member are the same direction.

According to such a configuration, the abutting direction in which the moving member abuts on the abutting member and the moving direction of the moving member are the same direction. Moving. Therefore, reliable contact between the moving member and the contact member can be ensured.
According to a third aspect of the present invention, in the second aspect of the present invention, the contact member is in contact with the moving member when the developing cartridge is mounted on the image forming apparatus main body. It is a feature.

  According to such a configuration, when the developing cartridge is attached to the image forming apparatus main body, the contact member contacts the moving member. That is, the moving member can be brought into contact with the contact member before the drive member is driven by the drive means. Therefore, if the contact result is detected by the detection means, the information determination means can determine information on the developing cartridge without driving the drive member by the drive means.

According to a fourth aspect of the present invention, in the invention according to any one of the first to third aspects, the driving member includes a tooth portion to which a driving force from the driving means is transmitted, and a driving force from the driving means. It is a missing tooth gear in which a missing tooth portion to which a driving force is not transmitted is formed.
According to such a configuration, while the drive force from the drive means is transmitted to the tooth portion, the drive member rotates, while the drive force from the drive means is not transmitted to the missing tooth portion. The rotation drive of the drive member is stopped. Therefore, the driving member can be reliably driven with a predetermined driving amount from the start of driving to the stop of driving.

According to a fifth aspect of the present invention, in the invention according to the fourth aspect, the developing cartridge transmits a driving force from the driving means when the developing cartridge is mounted on the image forming apparatus main body. And the chipped gear is meshed with the transmission gear.
According to such a configuration, since the chipped gear is meshed with the transmission gear, the chipped gear is reliably driven via the transmission gear by the driving force from the driving means. For this reason, information relating to the developing cartridge can be reliably determined by the information determining means by reliably driving the driving member.

According to a sixth aspect of the present invention, in the fifth aspect of the present invention, the developing cartridge urges the chipped gear toward the transmission gear so that the gears mesh with each other. It is characterized by having.
According to such a configuration, the chipped gear is biased toward the transmission gear by the biasing means so as to mesh with each other. Therefore, reliable engagement of the chipped gear and the transmission gear can be ensured, and more reliable driving of the chipped gear can be ensured.

The invention according to claim 7 is the invention according to any one of claims 1 to 6, wherein a plurality of the moving members are provided.
According to such a configuration, since a plurality of moving members are provided, if information relating to the developing cartridge is set corresponding to the number of moving members, the information determining means corresponds to the number of moving members. Information regarding a plurality of developing cartridges can be determined.

According to an eighth aspect of the present invention, in the invention according to any one of the first to seventh aspects, the number of the moving members corresponds to information relating to the developing cartridge, and the information determining means includes: Information on the developing cartridge is determined based on the number of detections of the moving member by the detecting means.
According to such a configuration, the number of moving members corresponds to information on the developing cartridge, and the information determining unit can determine information on a plurality of developing cartridges based on the number of times the moving member is detected by the detecting unit. it can.

The invention according to claim 9 is the invention according to any one of claims 1 to 7, wherein the moving member has a width along a moving direction corresponding to information on the developing cartridge, The information judging means judges information on the developing cartridge based on the detection time by the detecting means.
According to such a configuration, the width along the moving direction of the moving member corresponds to the information relating to the developing cartridge, and the information determining means determines the information relating to the plurality of developing cartridges based on the detection time of the moving member by the detecting means. Can be judged.

According to a tenth aspect of the present invention, in the invention according to any one of the first to ninth aspects, the information on the developing cartridge is information on whether or not the developing cartridge is new. Yes.
According to such a configuration, the information determination unit can easily and reliably determine whether or not the developing cartridge is new. For this reason, it is possible to determine the life of the developing cartridge from when a new article is detected.

According to an eleventh aspect of the present invention, in the invention according to any one of the first to ninth aspects, the information relating to the developing cartridge is a recording medium on which an image can be formed by a developer contained in the developing cartridge. It is the information regarding the maximum number of sheets.
According to such a configuration, the information determination unit can easily and reliably determine the maximum number of recording media on which an image can be formed with the developer contained in the developer cartridge. As a result, even if the amount of the developer is different in the developing cartridge, it is possible to accurately determine the lifetime and replace the developing cartridge accurately.

  According to a twelfth aspect of the present invention, in the developing cartridge that is detachable from the main body of the image forming apparatus and contains developer, the developing cartridge is mounted on the main body of the image forming apparatus. The image forming apparatus main body can be driven by a driving unit, and can be driven with a predetermined driving amount from the start of driving to the stop of driving, and can be moved along with the driving of the driving member. And a moving member that can pass through a detection position detected by the detection means provided.

  According to such a configuration, when the developing cartridge is mounted in the image forming apparatus main body, the driving member is driven by a predetermined driving amount from the driving start to the driving stop by the driving unit. Then, the moving member moves with the driving of the driving member, and the moving member passes the detection position of the detecting means, and the detecting means can detect the passage of the moving member. Information can be determined. For this reason, it is possible to cause the image forming apparatus to determine information related to the developing cartridge while reducing costs with a simple configuration.

In such a configuration, if a plurality of moving members are provided, the plurality of moving members can be passed through the detection position of the detection means when the developing cartridge is mounted on the image forming apparatus main body. As a result, in the image forming apparatus, information on the plurality of developing cartridges can be determined based on the result of detection of the plurality of moving members by the detecting unit.
The invention according to claim 13 is the invention according to claim 12, wherein the drive member is not transmitted with the tooth portion to which the drive force from the drive means is transmitted and the drive force from the drive means. It is a missing tooth gear formed with a missing tooth portion.

  According to such a configuration, when the developing cartridge is mounted on the image forming apparatus main body, while the driving force from the driving means is transmitted to the tooth portion, the driving member is driven to rotate while the tooth missing portion is When the driving force from the driving means is not transmitted, the rotational driving of the driving member is stopped. Therefore, the driving member can be reliably driven with a predetermined driving amount from the start of driving to the stop of driving.

  According to a fourteenth aspect of the present invention, in the developing cartridge that is detachable from the main body of the image forming apparatus and contains a developer, the developing cartridge is mounted on the main body of the image forming apparatus. The image forming apparatus main body includes a tooth portion that can be driven by the driving means provided in the image forming apparatus main body, to which the driving force from the driving means is transmitted, and a missing tooth portion to which the driving force from the driving means is not transmitted. A toothless gear that is driven with a predetermined driving amount from the driving to the stop of driving, and a movable member that is movable along with the driving of the toothless gear and is provided to face the middle of the tooth portion in the rotation direction of the toothless gear. It is characterized by having.

  According to such a configuration, when the developing cartridge is attached to the image forming apparatus main body, the chipped gear is driven to rotate while the driving force from the driving means is transmitted to the tooth portion, while the chipped tooth When the driving force from the driving means is not transmitted to the part, the rotational driving is stopped, so that it is driven with a predetermined driving amount from the start of driving to the stop of driving, and the driving of this chipped gear At the same time, the moving member moves. When this moving member is detected at the detection position by the detecting means so as to determine information related to the developing cartridge, the moving member is provided to face the middle of the tooth portion in the rotation direction of the missing gear. Therefore, compared with the case where it is provided at the end portion of the tooth portion, the detection position can be reliably passed with a smaller rotational drive amount of the chipped gear. For this reason, it is possible to reliably determine information relating to the developing cartridge in the image forming apparatus while reducing costs with a simple configuration.

According to a fifteenth aspect of the present invention, there is provided the transmission according to the thirteenth or fourteenth aspect, wherein the driving force from the driving unit is transmitted when the developing cartridge is mounted on the image forming apparatus main body. A gear is provided, and the chipped gear is meshed with the transmission gear.
According to such a configuration, since the chipped gear is meshed with the transmission gear, when the developing cartridge is mounted on the main body of the image forming apparatus, the chipped gear is moved by the driving force from the driving unit via the transmission gear. Driven reliably. Therefore, the information regarding the developing cartridge can be reliably determined in the image forming apparatus by the reliable driving of the driving member.

The invention described in claim 16 is the invention described in claim 15, further comprising urging means for urging the chipped gear toward the transmission gear so that they mesh with each other. It is characterized by.
According to such a configuration, the chipped gear is biased toward the transmission gear by the biasing means so as to mesh with each other. Therefore, reliable engagement of the chipped gear and the transmission gear can be ensured, and more reliable driving of the chipped gear can be ensured.

The invention according to claim 17 is the invention according to any one of claims 12 to 16, wherein a plurality of the moving members are provided.
According to such a configuration, since a plurality of moving members are provided, if information relating to the developing cartridge is set corresponding to the number of moving members, the image forming apparatus corresponds to the number of moving members. Information regarding a plurality of developing cartridges can be determined.

  The invention according to claim 18 is an image forming apparatus, wherein the main body of the image forming apparatus, a developing cartridge which is detachable from the main body of the image forming apparatus and contains a developer, and the image forming apparatus. A driving means provided in the apparatus main body and a developing cartridge provided in the developing cartridge, and when the developing cartridge is mounted on the image forming apparatus main body, can be driven by the driving means, and predetermined driving from the start of driving to the stop of driving A driving member that is driven by the amount, a moving member that is movable along with the driving of the driving member, and a detecting means that is capable of passing the moving member that is moved by driving the driving member and that detects the passage of the moving member And information determining means for determining information relating to the developing cartridge based on the detection result of the moving member by the detecting means. When the amount of developer accommodated in the developing cartridge is the first amount, the moving member is provided in the first number, and when the second amount is smaller than the first amount. Is provided in a second number greater than the first number, and the information determination means is configured to detect the number of detections detected by the detection means based on the passage of the moving member as the first number. When the number of times of detection corresponds to the second number, the developer amount stored in the developer cartridge is determined to be the first amount, and when the number of detections corresponds to the second number, It is characterized in that it is determined that the amount of developer accommodated in the developing cartridge is the second amount.

  As the number of moving members increases in the detecting means, the number of times of detection increases. Accordingly, even if the information judging means detects the moving member by the detecting means, the detection result is overlooked. There is a possibility that the number of detections is less than the number of detections of. For this reason, the second number larger than the first number may be erroneously determined as the first number smaller than the second number by the information determination unit due to oversight of the detection result by the information determination unit.

  When the developer amount stored in the developing cartridge is the second amount larger than the first amount, the moving member is provided in a second number larger than the first number. By overlooking the detection result by the information determining means as described above, in actuality, it should be determined as the number of detections corresponding to the second number, but it is determined as the number of detections corresponding to a smaller first number. There is a case. In such a case, the information determination unit causes the first amount that is smaller than the second amount even though the amount of developer contained in the developing cartridge is actually the second amount. It is judged as.

Then, in the image forming apparatus, when the developer stored in the developing cartridge is consumed in the first amount, it is determined that the replacement time has arrived, and the difference between the second amount and the first amount remains. This causes a problem such that the developing cartridge is replaced while the developer to be used is not consumed.
On the other hand, according to this configuration, when the amount of developer accommodated in the developing cartridge is the second amount smaller than the first amount, the moving member has the second number larger than the first number. Is provided. That is, the number of moving members corresponding to the first amount larger than the second amount is provided as the first number smaller than the second number. As described above, the first number is less likely to cause the detection result of the information determination unit to be overlooked than the second number, and therefore the first number corresponding to the first amount larger than the second amount. It is possible to reduce the possibility of erroneous determination of the number of detections of one. Therefore, it is possible to prevent the above-described problem, that is, the problem that the developer cartridge is replaced while the developer remaining in the difference between the second amount and the first amount is not consumed.

  Further, an invention according to claim 19 is the invention according to claim 18, in which the first quantity and the second quantity, the number of detection times of the detection means corresponding to the first number, and the first quantity The number of detections of the detection means corresponding to the number of two is provided with a storage means for storing a table associated with each of the number, and the information determination means refers to the storage means, When the number of detections is other than the number of detections associated with the table, the developer amount stored in the developer cartridge is determined to be the first amount.

  According to such a configuration, as a result of erroneously determining the noise input to the information determination means as a detection result, even when the detected number of detections is a detection number other than the number of detections associated with the table, The information determining means determines that the amount of developer accommodated in the developing cartridge is the first amount. Therefore, even if there is a misjudgment due to noise, it is possible to prevent problems such as the developer cartridge being replaced while the developer remaining in the difference between the second amount and the first amount is not consumed. Can do.

According to a twentieth aspect of the present invention, in the invention according to the eighteenth or nineteenth aspect, the driving unit determines a moving speed of the moving member during image formation when the detecting unit detects the moving member. Therefore, it is characterized in that it is decelerated as compared with the time of image formation.
According to such a configuration, the driving means decelerates the moving speed of the moving member during the detecting operation of the moving member as compared with the time of image formation for image formation. Passage can be detected, and the information determination unit can accurately determine the number of detections detected by the detection unit. As a result, it is possible to reliably determine the amount of developer accommodated in the developing cartridge.

According to the first aspect of the present invention, information relating to the developing cartridge can be determined with a simple configuration while reducing the cost. In addition, a plurality of moving members can be passed through the detection unit, whereby information on the plurality of developing cartridges can be determined by the information determination unit.
According to invention of Claim 2, reliable contact | abutting with a moving member and a contact member is securable.

According to the third aspect of the present invention, the information determination unit can determine information on the developing cartridge without driving the driving member by the driving unit.
According to invention of Claim 4, a drive member can be reliably driven with the predetermined drive amount from a drive start to a drive stop.
According to the fifth aspect of the present invention, the information determination means can reliably determine information relating to the developing cartridge.

According to the sixth aspect of the present invention, it is possible to ensure reliable engagement between the chipped gear and the transmission gear, and it is possible to ensure more reliable driving of the chipped gear.
According to the seventh aspect of the present invention, the information determination means can determine information relating to a plurality of developing cartridges corresponding to the number of moving members.
According to the eighth aspect of the present invention, the information determination unit can determine information related to a plurality of developing cartridges based on the number of detections of the moving member by the detection unit.

According to the ninth aspect of the present invention, the information determination unit can determine information regarding a plurality of developing cartridges based on the detection time of the moving member by the detection unit.
According to the tenth aspect of the present invention, it is possible to determine the life of the developing cartridge from when a new article is detected.
According to the eleventh aspect of the present invention, even if the amount of the developer is different in the developing cartridge, it is possible to accurately determine the lifetime and replace the developing cartridge accurately.

According to the twelfth aspect of the present invention, it is possible to cause the image forming apparatus to determine information relating to the developing cartridge while reducing costs with a simple configuration. Also, if a plurality of moving members are provided, the image forming apparatus can be made to determine information relating to a plurality of developing cartridges.
According to invention of Claim 13, a drive member can be reliably driven by the predetermined drive amount from a drive start to a drive stop.

According to the fourteenth aspect of the present invention, it is possible to reliably determine information relating to the developing cartridge in the image forming apparatus while reducing costs with a simple configuration.
According to the fifteenth aspect of the present invention, information relating to the developing cartridge can be reliably determined in the image forming apparatus by the reliable driving of the driving member.
According to the sixteenth aspect of the present invention, it is possible to ensure reliable engagement between the chipped gear and the transmission gear, and it is possible to ensure more reliable driving of the chipped gear.

According to the seventeenth aspect of the present invention, in the image forming apparatus, information relating to a plurality of developing cartridges can be determined in accordance with the number of moving members.
According to the eighteenth aspect of the present invention, it is possible to prevent problems such as the developer cartridge being replaced while the developer remaining by the difference between the second amount and the first amount is not consumed. .

According to the nineteenth aspect of the present invention, even if there is a misjudgment due to noise, the developer cartridge is replaced while the developer remaining in the difference between the second amount and the first amount is not consumed. It is possible to prevent problems such as end.
According to the twentieth aspect, it is possible to reliably determine the amount of developer accommodated in the developing cartridge.

1 is a side cross-sectional view showing a main part of a laser printer as an image forming apparatus of the present invention. FIG. 2 is a side view of a developing cartridge (gear cover mounted state) of the laser printer shown in FIG. 1. It is a side view of a developing cartridge (gear cover detached state). It is an operation view for explaining a new article detection mechanism (aspect having two contact protrusions), where (a) is a state before the developing cartridge is attached to the main body casing, and (b) is a state where the developing cartridge is the main body casing. (C) is a state in which the front side contact protrusion has passed through the actuator, and (d) is a state in which the rear side contact protrusion is in contact with the actuator. A state immediately before contact, (e) shows a state in which the rear contact protrusion is in contact with the actuator, and (f) shows a state in which the rear contact protrusion has passed through the actuator. FIG. 6 is an operation diagram for explaining a new article detection mechanism (a mode in which one abutment protrusion is narrow (narrow)), (a) is a state before mounting the developing cartridge to the main body casing, and (b) is A state in which the developing cartridge is mounted on the main body casing and the contact protrusion is in contact with the actuator, (c) is a state in which the contact protrusion has passed through the actuator, and (d) is a state immediately before the detection gear is stopped. FIG. 5 is an operation diagram for explaining a new article detection mechanism (a mode in which one abutment protrusion is wide (wide)), in which (a) shows a state in which the abutment protrusion is in contact with an actuator, and (b) shows a corresponding state. A state in which the contact protrusion is passing through the actuator, (c) shows a state in which the contact protrusion has passed through the actuator. It is a block diagram regarding the control system of a new article judgment process. It is a figure which shows the table memorize | stored in ROM shown in FIG. It is a timing diagram of a new article judgment process. It is a flowchart of a new article judgment process. FIG. 10 is a flowchart for determining that the new article determination process is an error when the detection count is not “2” in the new article determination process. It is a flowchart which shows a motor rotational speed judgment process. It is a timing diagram of a new article judgment process in the case of rotating a motor at half speed. It is a flowchart of a new article judgment process in the case of rotating a motor at half speed.

1. FIG. 1 is a side sectional view of an essential part showing a laser printer as an image forming apparatus of the present invention. The laser printer 1 includes a main body casing 2, a feeder unit 4 for feeding a paper 3 as a recording medium housed in the main body casing 2, and an image formed on the fed paper 3. The image forming unit 5 is provided.

(1) Main Body Casing An attachment / detachment opening 6 for attaching / detaching the process cartridge 20 is formed on one side wall of the main body casing 2, and a front cover 7 for opening / closing the attachment / detachment opening 6 is provided. . The front cover 7 is rotatably supported by a cover shaft (not shown) inserted through the lower end portion thereof. As a result, when the front cover 7 is closed around the cover shaft, as shown in FIG. 1, the attachment / detachment opening 6 is closed by the front cover 7 and when the front cover 7 is opened with the cover shaft as a fulcrum (when tilted), The attachment / detachment opening 6 is opened, and the process cartridge 20 can be attached to / detached from the main casing 2 through the attachment / detachment opening 6.

In the following description, in a state where the process cartridge 20 is mounted on the main casing 2, the side on which the front cover 7 is provided is referred to as “front side”, and the opposite side is referred to as “rear side”.
(2) Feeder unit The feeder unit 4 includes a paper feed tray 8 that is detachably attached to the bottom of the main body casing 2 along the front-rear direction, and a separation roller 9 that is provided above the front end of the paper feed tray 8. And a separation pad 10 and a paper feed roller 11 provided on the rear side of the separation roller 9 (upstream side of the separation pad 10 in the conveyance direction of the paper 3). The feeder unit 4 includes a paper dust removing roller 12 provided on the front upper side of the separation roller 9 (downstream side in the transport direction of the paper 3 with respect to the separation roller 9), and a pinch disposed to face the paper dust removing roller 12. And a roller 13.

The paper feed side transport path of the paper 3 is folded back to the rear side in a substantially U shape from the vicinity of the paper dust removing roller 12 and is further downstream in the transport direction and below the process cartridge 20 at the feeder section 4. Is provided with a registration roller 14 composed of a pair of rollers.
Inside the paper feed tray 8 is provided a paper pressing plate 15 on which the paper 3 can be stacked. The sheet pressing plate 15 is supported so as to be swingable at the rear end portion, so that the front end portion is disposed below, the placement position along the bottom plate 16 of the paper feed tray 8 and the front end portion are disposed above. Oscillating between the inclined supply position.

  A lever 17 for lifting the front end portion of the paper pressing plate 15 upward is provided at the front end portion of the paper feed tray 9. The lever 17 is supported at a position below the front end portion of the paper pressing plate 15 so that the rear end portion is swingably supported by the lever shaft 18, and the front end portion of the lever 17 is lying on the bottom plate 16 of the paper feed tray 8. The portion can swing between the inclined posture in which the sheet pressing plate 15 is lifted. When a rotational driving force is input to the lever shaft 18, the lever 17 rotates with the lever shaft 18 as a fulcrum, the front end of the lever 17 lifts the front end of the paper pressing plate 15, and the paper pressing plate 15 is fed to the supply position. Move to.

When the paper pressing plate 15 is positioned at the supply position, the paper 3 on the paper pressing plate 15 is pressed by the paper feeding roller 11, and the rotation of the paper feeding roller 11 causes the separation between the separation roller 9 and the separation pad 10. Paper feeding is started toward the separation position.
When the paper feed tray 8 is detached from the main casing 2, the front end of the paper pressing plate 15 moves downward due to its own weight, and the paper pressing plate 15 is positioned at the loading position. When the paper pressing plate 15 is positioned at the mounting position, the paper 3 can be stacked on the paper pressing plate 15.

  The sheet 3 sent out toward the separation position by the sheet feeding roller 11 is rolled and fed one by one when it is sandwiched between the separation roller 9 and the separation pad 10 by the rotation of the separation roller 9. Is done. The fed paper 3 passes between the paper dust removing roller 12 and the pinch roller 13, and after the paper dust is removed there, the paper 3 is folded back along the U-shaped paper feeding side conveying path, and the registration roller It is transported toward 14.

The registration roller 14 conveys the sheet 3 to the transfer position between the photosensitive drum 28 and the transfer roller 31 and to transfer the toner image on the photosensitive drum 28 to the sheet 3 after registration.
(3) Image Forming Unit The image forming unit 5 includes a scanner unit 19, a process cartridge 20, and a fixing unit 21.

(A) Scanner Unit The scanner unit 19 is provided in the upper part of the main casing 2 and includes a laser light source (not shown), a polygon mirror 22 that is driven to rotate, an fθ lens 23, a reflecting mirror 24, a lens 25, and a reflecting mirror 26. Yes. The laser beam based on the image data emitted from the laser light source is deflected by the polygon mirror 22 as shown by a chain line, passes through the fθ lens 23, then the optical path is turned back by the reflecting mirror 24, and further passes through the lens 25. After that, the light path is further bent downward by the reflecting mirror 26, so that the surface of the photosensitive drum 28 of the process cartridge 20 is irradiated.

(B) Process Cartridge The process cartridge 20 is provided below the scanner unit 19 in the main casing 2 and is detachably attached to the main casing 2.
The process cartridge 20 includes a process frame 27 and a photosensitive drum 28, a scorotron charger 29, a developing cartridge 30, a transfer roller 31, and a cleaning brush 32 in the process frame 27.

  The photosensitive drum 28 has a cylindrical shape, the outermost layer is formed of a positively chargeable photosensitive layer made of polycarbonate or the like, and an axial center of the drum main body 33 along the longitudinal direction of the drum main body 33. And a metal drum shaft 34 that extends. The drum shaft 34 is supported by the process frame 27, and the drum body 33 is rotatably supported by the drum shaft 34, so that the photosensitive drum 28 can be rotated about the drum shaft 34 in the process frame 27. Is provided. The photosensitive drum 28 is rotationally driven by the input of a driving force from a motor 59 (see FIG. 2).

  The scorotron charger 29 is supported by the process frame 27 obliquely above the rear side of the photosensitive drum 28, and is disposed opposite the photosensitive drum 28 so as not to contact the photosensitive drum 28. The scorotron charger 29 is provided between the discharge wire 35 and the photosensitive drum 28, which is disposed to face the photosensitive drum 28 with a space therebetween, and the amount of discharge from the discharge wire 35 to the photosensitive drum 28. And a grid 36 for controlling. In the scorotron charger 29, a bias voltage is applied to the grid 36 and at the same time, a high voltage is applied to the discharge wire 35 to cause corona discharge of the discharge wire 35, so that the surface of the photosensitive drum 28 is uniformly positive. To charge.

The developing cartridge 30 includes a casing 62 and a supply roller 37, a developing roller 38, and a layer thickness regulating blade 39 provided in the casing 62.
The developing cartridge 30 is detachably attached to the process frame 27. Therefore, the developing cartridge 30 can be attached to and detached from the main body casing 2 by attaching and detaching the developing cartridge 30 to and from the process cartridge 20 by opening and closing the front cover 7 with the process cartridge 20 attached to the main body casing 2. It can also be made.

  The housing 62 has a box shape with the rear side opened, and a partition plate 40 is provided in the middle of the front-rear direction so as to partition the inside of the housing 60. The front side of the housing 62 partitioned by the partition plate 40 is partitioned as a toner storage chamber 41 in which toner is stored. Further, the rear side of the housing 62 partitioned by the partition plate 40 is partitioned as a developing chamber 42 in which the supply roller 37, the developing roller 38, and the layer thickness regulating blade 39 are provided.

  In the toner storage chamber 41, positively charged nonmagnetic one-component toner is stored as a developer. In the toner, a polymerizable monomer, for example, a styrene monomer such as styrene, an acrylic monomer such as acrylic acid, alkyl (C1 to C4) acrylate, alkyl (C1 to C4) methacrylate, A polymerized toner obtained by copolymerization by suspension polymerization or the like is used. This polymerized toner has a substantially spherical shape, has extremely good fluidity, and can achieve high-quality image formation.

Such a toner is blended with a colorant such as carbon black, wax, and the like, and an external additive such as silica is added to improve fluidity. The average particle size of the toner is about 6 to 10 μm.
An agitator rotating shaft 43 is provided in the center of the toner storage chamber 41. The agitator rotating shaft 43 is rotatably supported on both side walls 44 arranged to face each other with a gap in the width direction of the casing 62 (a direction orthogonal to the front-rear direction and the up-down direction). The agitator rotating shaft 43 is provided with an agitator 45. The agitator 45 is rotated when a driving force from a motor 59 (see FIG. 2) is input to the agitator rotating shaft 43. When the agitator 45 is rotated, the toner in the toner storage chamber 41 is agitated and discharged toward the supply roller 37 from the opening 46 communicating in the front-rear direction below the partition plate 40.

  Note that toner detection windows 47 for detecting the remaining amount of toner stored in the toner storage chamber 41 are provided on the side walls 44 of the housing 62 at positions corresponding to the toner storage chamber 41. Yes. Each of the toner detection windows 47 is disposed so as to face the toner storage chamber 41 in the width direction. The main body casing 2 is provided with a toner empty sensor (not shown) including a light emitting element and a light receiving element. The light emitting element (not shown) is provided outside one toner detection window 47, and the other is used for toner detection. A light receiving element (not shown) is disposed outside the window 47, is emitted from the light emitting element, is incident on the toner storage chamber 41 through one toner detection window 47, and the other toner is transferred from the toner storage chamber 41. The detection light emitted through the detection window 47 is detected by a light receiving element, whereby the toner empty sensor determines the remaining amount of toner according to the frequency of detection of the detection light. When the amount of toner stored in the toner storage chamber 41 becomes small, a toner empty warning is displayed on an operation panel (not shown) or the like by the determination of the toner empty sensor.

  The supply roller 37 is disposed on the rear side of the opening 46. The supply roller 37 includes a metal supply roller shaft 48 and a sponge roller 49 made of a conductive foam material that covers the supply roller shaft 48. The supply roller shaft 48 is rotatably supported at a position corresponding to the developing chamber 42 on both side walls 44 of the housing 62. The supply roller 37 is rotationally driven when a driving force from a motor 59 (see FIG. 2) is input to the supply roller shaft 48.

  The developing roller 38 is disposed on the rear side of the supply roller 37 in contact with the supply roller 40 so as to be compressed. The developing roller 38 includes a metal developing roller shaft 50 and a rubber roller 51 made of a conductive rubber material that covers the developing roller shaft 50. The developing roller shaft 50 is rotatably supported at a position corresponding to the developing chamber 42 on both side walls 44 of the housing 62. The rubber roller 51 is made of conductive urethane rubber or silicone rubber containing carbon fine particles, and the surface thereof is coated with a urethane rubber or silicone rubber coating layer containing fluorine. The developing roller 38 is rotationally driven when a driving force from a motor 59 (see FIG. 2) is input to the developing roller shaft 50. A developing bias is applied to the developing roller 38 during development.

  The layer thickness regulating blade 39 includes a pressing portion 52 having a semicircular cross section made of insulating silicone rubber provided at a free end portion of a blade body made of a metal leaf spring material. In the layer thickness regulating blade 39, the base end portion of the blade body is supported by the casing 62 above the developing roller 38, so that the pressing portion 52 is pressed onto the developing roller 38 by the elastic force of the blade body. .

  The toner discharged from the opening 46 is supplied to the developing roller 38 by the rotation of the supply roller 37, and at this time, the toner is triboelectrically charged between the supply roller 37 and the developing roller 38. The toner supplied onto the developing roller 38 enters between the pressing portion 52 of the layer thickness regulating blade 39 and the rubber roller 51 of the developing roller 38 as the developing roller 8 rotates, and a thin layer having a constant thickness. Is carried on the developing roller 38.

  The transfer roller 31 is rotatably supported by the process frame 27, is provided below the photosensitive drum 28, contacts the photosensitive drum 28 in the vertical direction, and forms a nip with the photosensitive drum 28. Are arranged as follows. The transfer roller 31 includes a metal roller shaft and a rubber roller made of a conductive rubber material that covers the roller shaft. A transfer bias is applied to the transfer roller 31 during transfer. Further, the transfer roller 31 is rotationally driven by receiving a driving force from a motor 59 (see FIG. 2).

The cleaning brush 32 is attached to the process frame 27 and is disposed on the rear side of the photosensitive drum 28 so as to face and contact the photosensitive drum 28.
As the photosensitive drum 28 rotates, the surface of the photosensitive drum 28 is first uniformly charged to a positive polarity by the scorotron charger 29 and then exposed by high-speed scanning of the laser beam from the scanner unit 19. An electrostatic latent image corresponding to the image to be formed on the paper 3 is formed.

  Next, when the developing roller 38 rotates, the toner carried on the developing roller 38 and charged with positive polarity is formed on the surface of the photosensitive drum 28 when it comes into contact with the photosensitive drum 28. The electrostatic latent image, that is, the surface of the photosensitive drum 28 that is uniformly charged to the positive polarity, is supplied to the exposed portion exposed to a laser beam and having a lowered potential. As a result, the electrostatic latent image on the photosensitive drum 28 is visualized, and a toner image by reversal development is carried on the surface of the photosensitive drum 28.

Thereafter, the toner image carried on the surface of the photosensitive drum 28 is transferred to the transfer roller 31 while the sheet 3 conveyed by the registration roller 14 passes the transfer position between the photosensitive drum 28 and the transfer roller 31. Is transferred to the sheet 3 by the transfer bias applied to the sheet 3. The sheet 3 on which the toner image is transferred is conveyed to the fixing unit 21.
The transfer residual toner remaining on the photosensitive drum 28 after the transfer is collected by the developing roller 38. Further, the paper dust from the paper 3 adhering to the photosensitive drum 28 after the transfer is collected by the cleaning brush 32.

(C) Fixing Unit The fixing unit 21 is provided on the rear side of the process cartridge 20, and includes a fixing frame 53, and a heating roller 54 and a pressure roller 55 in the fixing frame 53.
The heating roller 54 includes a metal tube whose surface is coated with a fluororesin, and a halogen lamp for heating inserted in the metal tube. The heating roller 54 is rotationally driven when a driving force is input from a motor 59 (see FIG. 2).

The pressure roller 55 is disposed below the heating roller 54 so as to press the heating roller 54. The pressure roller 55 includes a metal roller shaft and a rubber roller made of a rubber material that covers the roller shaft. The pressure roller 55 is driven according to the rotational drive of the heating roller 54.
In the fixing unit 21, the toner image transferred onto the paper 3 at the transfer position is thermally fixed while the paper 3 passes between the heating roller 54 and the pressure roller 55. The sheet 3 on which the toner image is fixed is conveyed toward a sheet discharge tray 56 formed on the upper surface of the main casing 2.

The paper discharge side conveyance path of the sheet 3 from the fixing unit 21 to the paper discharge tray 56 is folded back from the fixing unit 21 to the front side in a substantially U shape. In the discharge side transfer path, a transfer roller 57 is provided in the middle, and a discharge roller 58 is provided at the downstream end.
The sheet 3 heat-fixed in the fixing unit 21 is conveyed to the sheet discharge side conveyance path, conveyed to the sheet discharge roller 58 by the conveyance roller 57, and then discharged onto the sheet discharge tray 56 by the sheet discharge roller 58. The

  A paper discharge sensor 60 is provided between the transport roller 57 and the paper discharge roller 58 in the paper discharge side transport path. The paper discharge sensor 60 swings every time the paper 3 transported in the paper discharge side transport path passes, and the number of times of the swing is determined by a CPU 90 (see FIG. 2) provided in the main body casing 2. The counted number is stored in a storage unit (not shown) (such as NVRAM 106 described later) as the number of images formed on the sheet 3.

In the laser printer 1, as will be described later, the CPU 90 (see FIG. 2) determines whether or not the developing cartridge 30 attached to the main casing 2 is a new one, and if the developing cartridge 30 is a new one, the developing cartridge 30 The maximum number of image forming sheets (described later) is determined, and the actual number of image forming sheets from when the new developing cartridge 30 is mounted is compared with the maximum number of image forming sheets (described later) of the developing cartridge 30. A toner empty warning is displayed on an operation panel (not shown) immediately after the actual number of image formation exceeds the maximum number of image formation (described later).
2. (A) Configuration of developer cartridge FIG. 2 is a side view of the developer cartridge (gear cover attached state), FIG. 3 is a side view of the developer cartridge (gear cover detached state), and FIG. FIG. 5 is an operation diagram for explaining a new article detection mechanism (an aspect with two contact protrusions), and FIG. 5 is an operation diagram for explaining a new article detection mechanism (an aspect with one contact protrusion).

2 and 3, in this developing cartridge 30, as shown in FIG. 3, the agitator rotating shaft 43 of the agitator 45, the supplying roller shaft 48 of the supplying roller 37, and the developing roller shaft 50 of the developing roller 38 are rotationally driven. As shown in FIG. 2, a gear mechanism 63 for this purpose and a gear cover 64 that covers the gear mechanism 63 are provided.
As shown in FIG. 3, the gear mechanism 63 is provided on one side wall 44 of the housing 62 of the developing cartridge 34. The gear mechanism 63 includes an input gear 65, a supply roller drive gear 66, a developing roller drive gear 67, an intermediate gear 68, an agitator drive gear 69 as a transmission gear, and a detection gear 70 as a drive member.

  The input gear 65 is rotatably supported between the developing roller shaft 50 and the agitator rotating shaft 43 by an input gear support shaft 71 protruding outward in the width direction from one side wall 44. A coupling receiving portion to which driving force from a motor 59 as driving means provided in the main body casing 2 is input to the shaft center of the input gear 65 when the developing cartridge 30 is mounted on the main body casing 2. 72 is provided.

The supply roller drive gear 66 is provided below the input gear 65 so as not to be relatively rotatable at the shaft end portion of the supply roller shaft 48 in a state of meshing with the input gear 65.
The developing roller drive gear 67 is provided at the shaft end portion of the developing roller shaft 50 so as not to rotate relative to the rear end of the input gear 65 obliquely below the input gear 65 so as to mesh with the input gear 65.
The intermediate gear 68 is rotatably supported by an intermediate gear support shaft 73 that protrudes outward in the width direction from one side wall 44 on the front side of the input gear 65. The intermediate gear 68 is a two-stage gear in which external teeth 74 that mesh with the input gear 65 and internal teeth 75 that mesh with the agitator drive gear 69 are integrally formed.

The agitator driving gear 69 is provided at a shaft end portion of the agitator rotating shaft 43 so as not to be relatively rotatable, obliquely below the front side of the intermediate gear 68. The agitator drive gear 69 is a two-stage gear in which an internal tooth 76 that meshes with the internal tooth 75 of the intermediate gear 68 and an external tooth 77 that meshes with the detection gear 70 are integrally formed.
The detection gear 70 is rotatably supported by a detection gear support shaft 78 projecting outward in the width direction from one side wall 44 at an obliquely upper front side of the input gear 65.

The detection gear 70 is formed as a missing tooth gear integrally including a detection gear main body 79, a tooth portion 80, a missing tooth portion 81, and a contact protrusion 82 as a moving member.
The detection gear main body 79 has a disk shape through which the detection gear support shaft 78 is inserted so as to be relatively rotatable at a center thereof, and a part of the detection gear main body portion 79 has a substantially fan-shaped notch 83 extending radially outward from the center. Is formed.

  The tooth portion 80 is partially provided on the outer peripheral surface of the detection gear main body portion 79. That is, the tooth portion 80 is formed in a substantially semicircular arc portion corresponding to a half-circumferential portion of the outer peripheral surface of the detection gear main body 79 from one circumferential end of the detection gear main body 79 to the other circumferential end. The external teeth 77 of the agitator drive gear 69 mesh with the tooth portion 80, and the driving force from the motor 59 is transmitted.

The missing tooth portion 81 is a portion other than the portion where the tooth portion 80 is formed on the outer peripheral surface of the detection gear main body 79, and the missing tooth portion 81 meshes with the outer teeth 77 of the agitator drive gear 69. Instead, transmission of the driving force from the motor 59 is interrupted.
The contact protrusion 82 is formed on the outer surface of the detection gear main body 79 as a protrusion that extends radially outward from the insertion portion through which the detection gear support shaft 78 is inserted toward the outer peripheral surface. The contact protrusion 82 has a distal end portion on the outer peripheral surface side that is wider than the proximal end portion on the insertion portion side, and the distal end portion is substantially L toward the rotation direction of the detection gear 70. A protruding portion 84 that protrudes in a letter shape is formed. In addition, the front-end | tip part of the contact protrusion 82 is formed in the curved shape so that a sharp angle | corner may not be formed including the protrusion part 84. FIG.

The number of the contact protrusions 82 is the maximum number of sheets 3 on which the image can be formed by the toner stored in the toner storage chamber 41 when the development cartridge 30 is new, as the number of the contact protrusions 82. Hereinafter, it is provided so as to correspond to the information on the maximum number of image formations).
More specifically, for example, as shown in FIG. 3 and FIG. 4, when two contact protrusions 82 are provided, the maximum image forming number is 6000, so as to correspond to the information. As shown in FIG. 5, when one contact protrusion 82 is provided, the contact protrusion 82 is provided so as to correspond to the information that the maximum image forming number is 3000 sheets.

  Further, the contact protrusion 82 passes through a detection position of an actuator 91 described later while the detection gear 70 is rotatable, that is, while the tooth portion 80 is engaged with the external tooth 77 of the agitator drive gear 69. The relative arrangement with the tooth part 80 is set so that More specifically, in FIG. 3, in the two contact projections 82, the tip end portion of the front contact projection 82 provided on the upstream side in the rotation direction of the detection gear 70 extends in the circumferential direction of the detection gear main body 79. It arrange | positions so that the middle (center) of the tooth | gear part 80 currently formed may be opposed. Further, the distal end portion of the rear contact protrusion 82 provided on the downstream side in the rotation direction of the detection gear 70 is downstream in the rotation direction of the detection gear 70 in the tooth portion 80 formed in the circumferential direction of the detection gear main body 79. It arrange | positions so that the outer side of an edge part may be opposed.

And this detection gear 70 is the state in which the insertion part of the detection gear main-body part 79 was inserted in the detection gear support shaft 78 so that relative rotation was possible, and the detection gear in the tooth part 80 by the coil spring 85 as a biasing means. The upstream end of the rotational direction 70 is biased so as to mesh with the external teeth 77 of the agitator drive gear 69.
The coil spring 85 is wound around the detection gear support shaft 78, one end of which is fixed to one side wall 44, and the other end is locked to the notch 83 of the detection gear main body 79. . As a result, the coil spring 85 is always detected in the rotational direction in which the upstream end of the tooth portion 80 in the rotational direction of the detection gear 70 faces the external teeth 77 of the agitator drive gear 69 and meshes with each other. The gear 70 is energized. For this reason, the upstream end of the tooth portion 80 in the rotation direction of the detection gear 70 and the external tooth 77 of the agitator drive gear 69 have been engaged with each other since the developing cartridge 30 is new. The urging force of the coil spring 85 is set larger than the urging force of a tension spring 97 (described later).

As shown in FIG. 2, the gear cover 64 is attached to one side wall 44 of the developing cartridge 30 so as to cover the gear mechanism portion 63. In the gear cover 64, an opening 86 for exposing the coupling receiving portion 72 is formed on the rear side. Further, a detection gear cover portion 87 that covers the detection gear 70 is formed on the front side thereof.
The detection gear cover portion 87 is formed so as to bulge outward in the width direction so that the detection gear 70 can be accommodated. A substantially fan-shaped detection window 88 is opened for exposing the contact protrusion 82 whose tip moves in the circumferential direction.

(B) Configuration of Main Body Casing In the main body casing 2, information on the mounted developing cartridge 30, more specifically, information on whether or not the mounted developing cartridge 30 is new, as described above, An information detection mechanism 89 serving as a detection unit and a CPU 90 serving as an information determination unit for detecting and determining information related to the maximum number of images formed on the development cartridge 30 when the development cartridge 30 is new. ing.

The information detecting mechanism 89 is provided on the inner wall surface of the main body frame 2 and is disposed on the rear side of the developing cartridge 30 in a state of being mounted on the main casing 2 as shown in FIG.
As shown in FIG. 4, the information detection mechanism 89 includes an actuator 91 and an optical sensor 92 as contact members.
The actuator 91 is swingably supported by a swing shaft 93 that protrudes inward in the width direction from the inner wall surface of the main casing 2. The actuator 91 includes a cylindrical insertion portion 94 through which the swing shaft 93 is inserted, an abutment claw portion 95 that extends forward from the insertion portion 94, and a light shielding portion 96 that extends rearward from the insertion portion 94. In preparation.

As shown in FIG. 4A, the contact claw portion 95 is disposed so as to extend slightly obliquely downward in a state where the light shielding portion 96 extends in a substantially horizontal direction. The light shielding portion 96 is formed to have a thickness in the vertical direction that can shield the detection light emitted from the optical sensor 92.
Further, the light blocking portion 96 is formed with a spring locking portion 98 in the middle in the longitudinal direction. One end of a tension spring 97 is locked to the spring locking portion 98. The tension spring 97 extends downward from the spring locking portion 98, and the other end is fixed to the inner wall surface of the main body casing 2 (not shown).

In addition, the insertion portion 94 is formed with a stopper projection 99 protruding outward in the radial direction above the outer peripheral surface. On the other hand, the main body casing 2 is provided with a stopper contact portion 100 that can contact the stopper protrusion 99 in the vicinity of the rear side of the stopper protrusion 99.
The actuator 91 is always urged so that the light shielding portion 96 is pulled downward by the tension spring 97 as shown in FIG. 4A, and this urging force causes the stopper projection 99 to contact the stopper. It is regulated by contacting the part 100. In this normal state, the actuator 91 is held such that the light shielding portion 96 extends substantially in the horizontal direction, and the insertion portion 94 extends slightly diagonally downward. The position where the contact claw 95 of the actuator 91 in this normal state is disposed is a detection position for detecting the passage of the contact protrusion 82 of the detection gear 70.

  As will be described in detail later, when the contact claw 95 comes into contact with the contact projection 82 of the detection gear 70 at the detection position, the contact claw 95 is pressed downward, so that the insertion portion The light shielding portion 96 swings upward and the abutment claw portion 95 swings downward against the urging force of the tension spring 97 with 94 as a fulcrum (see FIG. 4B). Moreover, the stopper protrusion 99 is separated from the stopper contact portion 100 by this swinging. Thereafter, when the contact of the contact protrusion 82 with the contact claw portion 95 is released, the insertion portion 94 is used as a fulcrum until the stopper protrusion 99 contacts the stopper contact portion 100 by the biasing force of the tension spring 97. The light shielding portion 96 swings downward, and the contact claw portion 95 swings upward (see FIG. 4C).

Although the optical sensor 92 does not appear in FIG. 4, a light emitting element and a light receiving element are provided on a holder member having a substantially U shape in a plan view, one of which is open so that the light emitting element and the light receiving element face each other with a space therebetween. And this optical sensor 92 is provided so that the light-shielding part 96 of the actuator 91 may be pinched | interposed with a holder member. More specifically, in the optical sensor 92, when the actuator 91 is in a normal state, detection light emitted from the light emitting element toward the light receiving element is shielded by the light shielding portion 96 (the state shown in FIG. 4A). As described above, when the contact protrusion 82 contacts the contact claw portion 95 and the light shielding portion 96 swings upward, the detection light emitted from the light emitting element toward the light receiving element is generated. The light receiving elements are arranged so as to receive light (the state shown in FIG. 4B).
3. Next, a description will be given of a method of mounting the developing cartridge 30 in the main casing 2 and determining whether the developing cartridge 30 is new or old and the maximum number of images formed on the developing cartridge 30.

(A) When there are two abutting projections First, as shown in FIG. 4A, the front cover 7 is opened, and the process cartridge 20 to which the new developing cartridge 30 is mounted is attached from the attachment / detachment opening 6. The main body casing 2 is mounted along the arrow A direction. Alternatively, the front cover 7 is opened, and a new developing cartridge 30 is attached to the process cartridge 20 attached to the main casing 2 through the attachment / detachment opening 6.

The detection gear 70 of the developing cartridge 30 is provided with two contact protrusions 82 as shown in FIG.
Then, as shown in FIG. 4B, when the developing cartridge 30 is mounted, the protrusion 84 of the contact protrusion 82 on the front side of the detection gear 70 is in contact with the normal actuator 91 at the detection position. The actuator 91 is in contact with the claw portion 95 so as to be directed downward from above, and against the urging force of the tension spring 97, the actuator 91 has the insertion portion 94 as a fulcrum and the contact claw portion 95 is in the downward direction. 96 swings upward (in the direction of arrow B). Then, in the normal state of the actuator 91, the detection light of the light sensor 92 that has been shielded from light is received by the light receiving element.

Then, a light reception signal based on this light reception is transmitted from the optical sensor 92 to the CPU 90. The CPU 90 recognizes this light reception signal as the first light reception signal and resets the counter.
When the developing cartridge 30 is mounted on the main casing 2, the driving force from the motor 59 provided in the main casing 2 is transmitted to the coupling receiving portion 72 of the input gear 65 of the developing cartridge 30. A coupling insertion portion (not shown) is inserted, and thereby, the input gear 65, the supply roller driving gear 66, the developing roller driving gear 67, the intermediate gear 68, the agitator driving gear 69 and the detection gear 70 of the gear mechanism portion 63 can be driven. It becomes.

Next, in the laser printer 1, when the developing cartridge 30 is mounted on the main casing 2, a warming-up operation is started under the control of the CPU 90, and a glass turning operation is performed in which the agitator 45 is rotated.
In the loosening operation, the motor 59 provided in the main body casing 2 is driven by the control of the CPU 90, and the driving force is input from the coupling insertion portion to the developing cartridge 30 via the coupling receiving portion 72. The gear 65 is input, and the input gear 65 is rotationally driven. Then, as shown in FIG. 3, the supply roller drive gear 66 meshing with the input gear 65 is rotationally driven, and the supply roller 37 is rotated by the rotation of the supply roller shaft 48. Further, the developing roller driving gear 67 meshed with the input gear 65 is rotationally driven, and the developing roller 38 is rotated by the rotation of the developing roller shaft 50. Further, the external teeth 74 of the intermediate gear 68 meshing with the input gear 65 are rotationally driven, and the internal teeth 75 of the intermediate gear 68 formed integrally with the external teeth 74 are rotationally driven. When the inner teeth 75 of the intermediate gear 68 are rotationally driven, the inner teeth 76 of the agitator driving gear 69 meshing with the inner teeth 75 of the intermediate gear 68 are rotationally driven, and the agitator 45 is rotated by the rotation of the agitator rotating shaft 43. Is rotated. By the rotation of the agitator 45, the toner in the toner storage chamber 41 is stirred and fluidized.

When the inner teeth 76 of the agitator driving gear 69 are rotationally driven, the outer teeth 77 of the agitator driving gear 69 formed integrally with the inner teeth 76 are rotationally driven. Then, the detection gear 70 in which the tooth portion 80 meshes with the external teeth 77 of the agitator drive gear 69 is rotationally driven by a predetermined drive amount from the start of rotational drive to the stop of rotational drive.
That is, the detection gear 70 is rotationally driven in the direction of the arrow C only while the tooth portion 80 meshes with the external tooth 77 of the agitator drive gear 69, so that the detection gear 70 is formed on the half peripheral portion of the outer peripheral surface of the detection gear body 79. Corresponding to the tooth portion 80, the detection gear support shaft 78 is driven about one half rotation in one direction, and then stopped. The detection gear 70 is held in a stopped state by frictional resistance with the detection gear support shaft 78 after being stopped.

  In such rotation driving of the detection gear 70, when the rotation driving of the detection gear 70 is started, as shown in FIG. 4B, the contact of the actuator 91 occurs when the developing cartridge 30 is mounted. From above, the protrusion 84 of the contact protrusion 82 on the front side of the detection gear 70 that is in contact with the claw 95 is in the same direction as the contact direction in which the protrusion 84 contacts the contact claw 95. It is moved in one circumferential direction so as to go downward. Then, the projecting portion 84 further presses the contact claw portion 95 while sliding with the contact claw portion 95, and then passes through the contact claw portion 95 as shown in FIG. It is separated from the contact claw part 95. Thus, when the contact of the protruding portion 84 with the contact claw portion 95 is released, the biasing force of the tension spring 97 causes the actuator 91 to move the contact claw portion 95 upward and the light shielding portion with the insertion portion 94 as a fulcrum. 96 swings downward (in the direction of arrow D), and the actuator 91 returns to the normal state. Then, the detection light of the optical sensor 92 received by the light receiving element is blocked by the light blocking unit 96.

  Thereafter, when the detection gear 70 is further driven to rotate, as shown in FIG. 4D, the protruding portion 84 of the rear contact protrusion 82 is brought into contact with the contact claw portion 95 of the normal actuator 91 at the detection position. On the other hand, it abuts from the upper side to the lower side. Then, as shown in FIG. 4 (e), the actuator 91 again resists the biasing force of the tension spring 97, with the insertion portion 94 as a fulcrum, the contact claw portion 95 downward, and the light shielding portion 96 upward. The light detected by the optical sensor 92 is received by the light receiving element. Then, a light reception signal based on this light reception is transmitted from the optical sensor 92 to the CPU 90. The CPU 90 recognizes this light reception signal as the second light reception signal.

  Thereafter, the projecting portion 84 further presses the contact claw portion 95 while sliding with the contact claw portion 95, and then passes through the contact claw portion 95 as shown in FIG. It is separated from the contact claw part 95. Thus, when the contact of the protruding portion 84 with the contact claw portion 95 is released, the biasing force of the tension spring 97 causes the actuator 91 to move the contact claw portion 95 upward and the light shielding portion with the insertion portion 94 as a fulcrum. The actuator 96 swings downward and the actuator 91 returns to the normal state. Then, the detection light of the optical sensor 92 received by the light receiving element is blocked by the light blocking unit 96.

Thereafter, the meshing between the tooth portion 80 of the detection gear 70 and the external teeth 77 of the agitator drive gear 69 is released, and the rotation drive of the detection gear 70 is stopped.
In such a glass turning operation, the CPU 90 determines whether or not the developing cartridge is a new one based on whether or not a light receiving signal is input, and determines the maximum number of images formed on the developing cartridge 30 based on the number of times the light receiving signal is input. Judging.

That is, as described above, in the example shown in FIG. 4, when the CPU 90 recognizes the first light reception signal, the CPU 90 determines that the developing cartridge 30 is new.
Further, in the CPU 90, the number of received light signal inputs is associated with information related to the maximum number of formed images. More specifically, for example, when the number of light reception signal inputs is two, the maximum number of image formations is 6000, and when the number of light reception signal inputs is one, the maximum number of image formations is 3000. It is associated with the information that it is a sheet.

As described above, in the example illustrated in FIG. 4, when the CPU 90 recognizes the first light reception signal and the second light reception signal, that is, the two light reception signals before the end of the glass turning operation, It is determined that the maximum number of image forming sheets of the new developing cartridge 30 is 6000 sheets.
As a result, in the example shown in FIG. 4, when the developing cartridge 30 is mounted, the CPU 90 determines that the developing cartridge 30 is new and the maximum number of images to be formed on the developing cartridge 30 is 6000. When the developing cartridge 30 is mounted, a toner empty warning is displayed on an operation panel (not shown) or the like immediately after the actual number of formed images detected by the paper discharge sensor 60 exceeds 6000.

  On the other hand, after the new developing cartridge 30 is mounted, when the developing cartridge 30 is once detached from the main body casing 2 due to, for example, jamming of the paper 3, and is mounted in the main body casing 2 again, the detection gear 70 Is held at a position where the tooth portion 80 does not mesh with the external teeth 77 of the agitator drive gear 69 (see FIG. 4F). For this reason, even when the gear 90 is rotated under the control of the CPU 90 in the remounting, the detection gear 70 is not rotationally driven, and any of the contact protrusions 82 does not pass the detection position of the actuator 91. For this reason, there is no input of a light reception signal from the optical sensor 92 to the CPU 90, and the CPU 92 does not erroneously determine that the re-installed developing cartridge 30 (old developing cartridge) is a new one. The comparison between the maximum number of image formations at the time of determination and the actual number of image formations on the sheet 3 from when it is determined as new is continued.

(B) When there is one abutting projection First, as shown in FIG. 5A, the front cover 7 is opened, and the process cartridge 20 with a new developing cartridge 30 is attached to the main body through the attachment / detachment opening 6. Mount on the casing 2. Alternatively, the front cover 7 is opened, and a new developing cartridge 30 is attached to the process cartridge 20 attached to the main casing 2 through the attachment / detachment opening 6.

The detection gear 70 of the developing cartridge 30 is provided with only one contact protrusion 82 as shown in FIG. The one abutting protrusion 82 corresponds to the abutting protrusion 82 on the front side of the two abutting protrusions 82 shown in FIG. 4 and corresponds to the abutting protrusion 82 on the rear side. 82 is not provided.
Then, as shown in FIG. 5B, when the developing cartridge 30 is mounted, the protrusion 84 of the contact protrusion 82 of the detection gear 70 is in the detection position, and the contact claw 95 of the normal actuator 91 is in the detection position. Against the urging force of the tension spring 97, the actuator 91 uses the insertion portion 94 as a fulcrum, the contact claw portion 95 is downward, and the light shielding portion 96 is upward. Swing to head toward. Then, in the normal state of the actuator 91, the detection light of the light sensor 92 that has been shielded from light is received by the light receiving element.

Then, a light reception signal based on this light reception is transmitted from the optical sensor 92 to the CPU 90. The CPU 90 recognizes this light reception signal as the first light reception signal.
When the developing cartridge 30 is mounted on the main casing 2, the driving force from the motor 59 provided in the main casing 2 is transmitted to the coupling receiving portion 72 of the input gear 65 of the developing cartridge 30. A coupling insertion portion (not shown) is inserted, and thereby, the input gear 65, the supply roller driving gear 66, the developing roller driving gear 67, the intermediate gear 68, the agitator driving gear 69 and the detection gear 70 of the gear mechanism portion 63 can be driven. It becomes.

Next, in the laser printer 1, when the developing cartridge 30 is mounted on the main casing 2, the warming-up operation is started under the control of the CPU 90, and the glass turning operation for rotating the agitator 45 is executed as described above. .
In this gear turning operation, the detection gear 70 is rotationally driven only while the tooth portion 80 is engaged with the external tooth 77 of the agitator drive gear 69, as described above. Corresponding to the tooth portion 80 formed in the half-circumferential part of the motor, the motor is stopped after being driven approximately ½ rotation in one direction around the detection gear support shaft 78. The detection gear 70 is held in a stopped state by frictional resistance with the detection gear support shaft 78 after being stopped.

  In such rotational driving of the detection gear 70, when the rotational driving of the detection gear 70 is started, as shown in FIG. 5B, the contact of the actuator 91 occurs when the developing cartridge 30 is mounted. The protrusion 84 of the contact protrusion 82 of the detection gear 70 that is in contact with the claw 95 is in the same direction as the contact direction in which the protrusion 84 is in contact with the contact claw 95, from above to below. So that it is moved in one circumferential direction. Then, the projecting portion 84 further presses the contact claw portion 95 while sliding with the contact claw portion 95, and then passes through the contact claw portion 95 as shown in FIG. It is separated from the contact claw part 95. Thus, when the contact of the protruding portion 84 with the contact claw portion 95 is released, the biasing force of the tension spring 97 causes the actuator 91 to move the contact claw portion 95 upward and the light shielding portion with the insertion portion 94 as a fulcrum. The actuator 96 swings downward and the actuator 91 returns to the normal state. Then, the detection light of the optical sensor 92 received by the light receiving element is blocked by the light blocking unit 96.

Thereafter, the meshing between the tooth portion 80 of the detection gear 70 and the external teeth 77 of the agitator drive gear 69 is released, and the rotation drive of the detection gear 70 is stopped.
In such a rattling operation, the CPU 90 determines whether or not the developing cartridge is new based on whether or not a light receiving signal is input, and determines the developing cartridge 30 based on the number of times the light receiving signal is input, as described above. The maximum number of images formed is determined.

That is, in the example shown in FIG. 5, first, when the CPU 90 recognizes the first light reception signal, the CPU 90 determines that the developing cartridge 30 is new.
In the example shown in FIG. 5, when the CPU 90 recognizes the first light reception signal, that is, one light reception signal before the end of the glass turning operation, the CPU 90 determines the maximum number of image forming sheets of the new developing cartridge 30. Is determined to be 3000 sheets.

  As a result, in the example shown in FIG. 5, when the developing cartridge 30 is mounted, the CPU 90 determines that the developing cartridge 30 is new and the maximum number of images to be formed on the developing cartridge 30 is 3000. A toner empty warning is displayed on an operation panel (not shown) from when the developing cartridge 30 is mounted to when the actual number of formed images detected by the paper discharge sensor 60 exceeds 3000.

On the other hand, after the new developing cartridge 30 is mounted, when the developing cartridge 30 is once detached from the main body casing 2 due to, for example, jamming of the paper 3, and is mounted in the main body casing 2 again, the detection gear 70 Is held at a position where the tooth portion 80 does not mesh with the external teeth 77 of the agitator drive gear 69 (see FIG. 5D). For this reason, even when the gear 90 is rotated under the control of the CPU 90 during remounting, the detection gear 70 is not rotationally driven, and the contact protrusion 82 does not pass through the detection position of the actuator 91. For this reason, there is no input of a light reception signal from the optical sensor 92 to the CPU 90, and the CPU 92 does not erroneously determine that the re-installed developing cartridge 30 (old developing cartridge) is a new one. The comparison between the maximum number of image formations at the time of determination and the actual number of image formations on the sheet 3 from when it is determined as new is continued.
4). Effects on New Detection of Developer Cartridge According to this racer printer 1, when the developer cartridge 30 is mounted on the main casing 2, the motor 59 causes the detection gear 70 to rotate only half of the rotation from the start of rotation to the stop of rotation. Driven by rotation. Then, the contact protrusion 82 moves in the circumferential direction along with the rotation of the detection gear 70, passes through the detection position of the actuator 91, and the passage of the contact protrusion 82 is detected by the optical sensor 92. Then, the CPU 90 determines whether or not the developing cartridge 30 is new based on whether or not the contact protrusion 82 is detected by the optical sensor 92. Therefore, it is possible to determine whether or not the developing cartridge 30 is new with a simple configuration while reducing the cost.

  In the racer printer 1, the contact claw portion 95 of the actuator 91 passes through the contact protrusion 82 to detect the presence or absence of the contact protrusion 82. A plurality of contact protrusions 82 can be passed through. As a result, the CPU 90 determines whether or not the developing cartridge 30 is new in addition to determining whether or not the developing cartridge 30 is new based on whether or not the plurality of contact protrusions 82 are detected by the optical sensor 92. A maximum image forming number of 30 can also be determined.

Moreover, in the detection gear 70, the contact protrusion 82 is provided so as to face the middle of the tooth portion 80 in the rotation direction of the detection gear 70, so that it is provided so as to face the end portion of the tooth portion 80. Compared with the case where the detection gear 70 is present, the detection position can be reliably passed with a smaller rotational drive amount of the detection gear 70.
In the racer printer 1, the contact direction in which the protrusion 84 of the contact protrusion 82 contacts the contact claw 95 of the actuator 91 and the movement direction in which the protrusion 84 moves in the circumferential direction are the same direction. Therefore, when the protruding portion 84 contacts the contact claw portion 95, it moves in the moving direction as it is. Therefore, reliable contact between the protruding portion 84 and the contact claw portion 95 can be ensured.

  In the racer printer 1, the projecting portion 84 contacts the contact claw portion 95 when the developing cartridge 30 is mounted on the main body casing 2. That is, the protruding portion 84 can be brought into contact with the contact claw portion 95 before the gear 59 is rotated by the motor 59. Therefore, if the presence or absence of the contact is detected by the optical sensor 92, the CPU 90 can determine whether or not the developing cartridge 30 is a new product without rotating the detection gear 70 by the motor 59.

  The detection gear 70 is composed of a missing gear, and while the driving force from the motor 59 is transmitted to the tooth portion 80, the detection gear 70 is driven to rotate, while the missing gear portion 81 is driven from the motor 59. When the driving force is not transmitted, the rotational driving of the detection gear 70 is stopped. Therefore, the detection gear 70 can be reliably rotated with a predetermined drive amount from the start of rotation drive to the stop of rotation drive.

  In the developing cartridge 30, the detection gear 70 is urged by the coil spring 85 toward the external teeth 77 of the agitator driving gear 69 so as to mesh with each other, and the detection gear 70 and the agitator driving gear 69 are thus urged. The positive engagement with the external teeth 77 is ensured. Therefore, the detection gear 70 is reliably driven via the external teeth 77 of the agitator driving gear 69 by the driving force from the motor 59. Therefore, by reliably driving the detection gear 70, the CPU 90 can reliably determine the maximum number of images formed on the developing cartridge 30 when the developing cartridge 30 is determined to be new.

  In the laser printer 1, the developing cartridge 30 is provided with one or two abutting protrusions 82, so that information on the maximum number of images formed on the developing cartridge 30 corresponds to the number of the abutting protrusions 82. Therefore, the CPU 90 easily and reliably determines information related to the maximum number of formed images of the developing cartridge 30 based on the number of detections of the contact protrusion 82 of the optical sensor 92 (the number of times of input of the light reception signal). be able to. Therefore, in the developing cartridge 30, even if the amount of toner differs corresponding to the maximum number of images formed, it is possible to accurately determine the life and replace the developing cartridge 30 accurately.

In the laser printer 1, the CPU 90 determines whether or not the mounted developing cartridge 30 is a new one depending on whether or not the optical sensor 92 detects the contact protrusion 82 of the mounted developing cartridge 30. Since it is determined, whether the developing cartridge 30 is new or old can be easily and reliably determined. Therefore, it is possible to reliably determine the life of the developing cartridge 30 from when a new article is detected.
5). In the above embodiment, the number of the contact protrusions 82 is made to correspond to the maximum number of images to be formed on the developing cartridge 30. However, as shown in FIG. The width in the circumferential direction of the tip including the protruding portion 84 can be made to correspond to the maximum number of images formed by the developing cartridge 30.

That is, for example, as shown in FIG. 6, when the width of the tip end portion of the contact protrusion 82 is formed wide, it corresponds to the information that the maximum image forming number is 6000, as shown in FIG. As shown in FIG. 4, when the width of the tip of the contact protrusion 82 is narrow, the contact protrusion 82 is formed so as to correspond to the information that the maximum number of image formation is 3000 sheets. .
Further, the CPU 90 determines the maximum number of image formations corresponding to the input time of the light reception signal from the optical sensor 92 from the start of driving of the motor 59.

  Accordingly, in FIG. 5, the rotation of the detection gear 70 starts from the start of rotation of the detection gear 70, and the detection gear 70 that is in contact with the contact claw 95 of the actuator 91 as shown in FIG. Corresponding to the time until the protrusion 84 of the contact protrusion 82 passes through the contact claw 95 while sliding with the contact claw 95, the CPU 90 receives a short light reception signal from the optical sensor 92. Entered in time.

  On the other hand, in FIG. 6, the rotation of the detection gear 70 starts from the start of rotation of the detection gear 70, and the contact of the detection gear 70 that is in contact with the contact claw portion 95 of the actuator 91 as shown in FIG. As shown in FIG. 6C, the protrusion 84 of the contact projection 82 slides on the contact claw 95 as shown in FIG. 6B until it passes through the contact claw 95. Corresponding to the time, a light reception signal is input to the CPU 90 from the optical sensor 92 in a long time.

Then, the CPU 90 determines that the maximum image forming number is 3000, for example, when the light receiving time is short, and the maximum image forming number is 6000 when the light receiving time is long. Set so that it is judged to be a sheet.
In this way, even if a plurality of contact protrusions 82 are not formed, the CPU 90 only changes the width of the tip of the contact protrusion 82 and based on the detection time of the contact protrusion 82 by the optical sensor 92. Then, the maximum number of image forming sheets of the developing cartridge 30 can be determined.
6). Modification regarding the relationship between the number of contact protrusions and the maximum number of image formations In the above description, when two contact protrusions 82 are provided, the maximum number of image formations is 6000. In the case where one contact projection 82 is provided, the information is that the maximum number of images to be formed is 3000. On the contrary, one contact projection 82 is provided. In this case, it corresponds to the information that the maximum image forming number is 6000, and in the case where two contact projections 82 are provided, it can correspond to the information that the maximum image forming number is 3000. it can.

Next, with reference to FIG. 7 to FIG. 10, the control of the new article determination process for judging the new and old development cartridges 30 and the maximum number of image forming sheets of the development cartridges 30 in such a case will be described. This will be described in detail.
7 is a block diagram related to the control system of the new article determination process, FIG. 8 is a diagram showing a table stored in the ROM shown in FIG. 7, FIG. 9 is a timing chart of the new article determination process, and FIG. It is a flowchart of a process.

As shown in FIG. 7, in this control system, the motor 59, the optical sensor 92, and the front cover open / close detection sensor 102 are connected to the ASIC 101 for controlling each part of the laser printer 1.
The motor 59 is controlled by the ASIC 101 by executing various programs of the CPU 90.

The optical sensor 92 inputs the above-described received light signal to the CPU 90 via the ASIC 101.
Although not shown, the front cover open / close detection sensor 102 includes a switch that is turned on when the front cover 7 abuts. The front cover open / close detection sensor 102 is turned on when the opened front cover 7 is closed, and sends a close detection signal via the ASIC 101. To the CPU 90.

The ASIC 101 is connected to a ROM 104, a RAM 105, an NVRAM 106, and a CPU 90 as storage means via a bus 103.
The ROM 104 stores various programs executed by the CPU 90, such as an image formation processing program for image formation processing, a new article determination processing program for executing a new article determination process, and, if necessary, motor rotation speed determination. A motor rotation speed determination processing program for executing the processing is stored. In addition, the ROM 104 stores a table 107 in which the toner capacity of the developing cartridge 30 and the number of detections are referred to that are referred to in the new article determination process.

As shown in FIG. 8, this table 107 shows that the number of detections of the contact protrusion 82 of the optical sensor 92 (the number of times of input of the received light signal) is 1 (that is, the detection frequency count described later is “1”). Corresponds to “high capacity” and is associated with “low capacity” when the number of detections is 2 (that is, when the detection number count described later is “2”). .
“High capacity” indicates that the developing cartridge 30 (hereinafter referred to as “high capacity developing cartridge”) having a high capacity corresponding to the maximum number of image forming sheets of 6000 and containing toner is referred to as “low capacity”. Indicates a low-capacity developing cartridge 30 (hereinafter referred to as a low-capacity developing cartridge) corresponding to a maximum image forming number of 3000 sheets.

The RAM 105 stores temporary numerical values when various programs are executed. Further, the NVRAM 106 stores the presence / absence of input of the light reception signal of the optical sensor 92, the measurement time of the light reception signal (see FIG. 9), and the number of times of light reception (number of detections).
In such a control system, the new article determination process is executed by the CPU 90 executing the new article determination process program stored in the ROM 104 and the ASIC 101 controlling each unit.

Next, the new article determination process will be described with reference to FIG. 9 and FIG.
As described above, in this new article determination process, the developing cartridge 30 provided with one contact projection 82 (first number) has a high capacity (first amount) corresponding to the maximum number of images to be formed 6000. The developing cartridge 30 having two contact projections 82 (second number) is a low-capacity developing cartridge corresponding to a maximum number of 3000 sheets (second number). A low-capacity developing cartridge in which toner is contained.

First, referring to FIG. 9, on / off timing of the optical sensor 92 when a new high-capacity developing cartridge, a new low-capacity developing cartridge, and an old developing cartridge are mounted on the main casing 2. Will be described.
When a new high-capacity developing cartridge is mounted on the main casing 2, as described above, when the new high-capacity developing cartridge is mounted, the protruding portion 84 of the contact protrusion 82 is in the detection position. The actuator 91 swings in contact with the contact claw portion 95 of the normal actuator 91, and the optical sensor 92 is turned on (that is, a light reception signal is input to the CPU 90).

  Next, when the motor 59 is driven at full speed under the control of the CPU 90 and the gear-turning operation is performed, the protrusion 84 further presses the contact claw 95 while sliding with the contact claw 95. The optical sensor 92 is turned off (ie, the input of the light reception signal to the CPU 90 is stopped) by moving away from the contact claw portion 95 and swinging the actuator 91. It should be noted that the time from the start of the rotation operation until the optical sensor 92 is turned off is 0.3 seconds when the motor 59 is driven at full speed.

  That is, when a new high-capacity developer cartridge is mounted on the main casing 2, the number of times the light sensor 92 is turned on / off (number of times of light reception) is one. In such on / off of the optical sensor 92, the on-continuation state for a predetermined time (0.3 seconds) is once within a set time (for example, 5 seconds) from the start of driving of the motor 59. Is counted as the number of times of detection (the same applies hereinafter).

Further, when a new low-capacity developing cartridge is mounted on the main casing 2, as described above, when the new low-capacity developing cartridge is mounted, the protruding portion 84 of the front contact projection 82 is At the detection position, the actuator 91 comes into contact with the contact claw portion 95 of the normal actuator 91, and the optical sensor 92 is turned on.
Next, when the motor 59 is driven at full speed under the control of the CPU 90 and a loosening operation is performed, the front protrusion 84 further presses the contact claw 95 while sliding with the contact claw 95. After that, the optical sensor 92 is turned off by moving the actuator 91 away from the contact claw portion 95. It should be noted that the time from the start of the rotation operation until the optical sensor 92 is turned off is 0.3 seconds when the motor 59 is driven at full speed.

  Thereafter, the protruding portion 84 of the rear-side contact protrusion 82 contacts the contact claw portion 95 of the normal actuator 91, the actuator 91 swings, and the optical sensor 92 is turned on again. The time from when the optical sensor 92 is turned off to when the optical sensor 92 is turned on again is 1.1 seconds (that is, when the motor 59 is driven at full speed, that is, from the start of the rotation operation) The time until the sensor 92 is turned on again is 1.4 seconds when the motor 59 is driven at full speed.

  Then, the rear protruding portion 84 slides on the contact claw portion 95 and further presses the contact claw portion 95, and then moves away from the contact claw portion 95. 92 is turned off again. Note that the time from when the optical sensor 92 is turned on again to when the optical sensor 92 is turned off again is 0.3 seconds (that is, from the start of the glass turning operation) when the motor 59 is driven at full speed. The time until the optical sensor 92 is turned off again is 1.7 seconds when the motor 59 is driven at full speed.

That is, when a new low-capacity developer cartridge is mounted on the main casing 2, the number of times the light sensor 92 is turned on / off (number of times of light reception) is two.
On the other hand, when the old development cartridge (that is, the old high-capacity development cartridge or the old low-capacity development cartridge) is mounted on the main casing 2, the detection gear 70 is stopped as described above. Since the contact protrusion 82 does not pass the detection position of the actuator 91, the optical sensor 92 is not turned on but is kept off.

That is, when an old developing cartridge is mounted on the main casing 2, the number of times the photosensor 92 is turned on / off (number of times of light reception) is zero.
Next, a new article determination process performed by the CPU 90 will be described with reference to FIG. In FIG. 10, in this new article determination process, it is first determined whether the power is turned on or whether a closing detection signal is input to the CPU 90 (S1). If neither the power is turned on nor the closing detection signal is input to the CPU 90 (S1: NO), the process returns to the main routine (not shown) and the determination in step 1 is continued. On the other hand, when either the power is turned on or the closing detection signal is input to the CPU 90 (S1: YES), the above-described glass turning operation is started (S2).

As described above, when the front cover 7 is opened and the developing cartridge 30 is attached to the main body casing 2 from the attachment / detachment opening 6 and then the front cover 7 is closed, the front cover open / close detection sensor 102 is turned on and closed. Since the detection signal is input to the CPU 90, the rotation operation is started (S2).
When the glass turning operation is started, it is determined whether or not the glass turning operation is finished (S3). If the glass turning operation has not ended (S3: NO), that is, during the glass turning operation, it is first determined whether or not the optical sensor 92 is turned on (a light reception signal is input) (S4). When the optical sensor 92 is turned on (S4: YES), the time during which the optical sensor 92 is turned on is measured (S5). The time during which the optical sensor 92 is turned on is continuously measured while the optical sensor 92 is turned on during the rotation operation, and the measured time is stored in the NVRAM 106 (S3: NO, S4: YES, S5).

  When the optical sensor 92 is turned off (S4: NO), it is determined whether or not the time during which the optical sensor 92 is turned on is 0.3 seconds or longer (S6). When the time during which the optical sensor 92 is on is 0.3 seconds or longer (S6: YES), the contact protrusion 82 contacts the contact claw portion 95 at the contact position as described above. Therefore, it is determined that this is an input of the received light signal, the number of times of detection is counted up (S7), and the count of the number of times of detection stored in the NVRAM 106 is incremented. Thereafter, the ON measurement time of the optical sensor 92 stored in the NVRAM 106 is cleared (S8).

On the other hand, when the time during which the optical sensor 92 is on is less than 0.3 seconds (S6: NO), it is determined that the contact is not a contact between the contact protrusion 82 and the contact claw portion 95 but a noise signal. Therefore, the ON measurement time of the optical sensor 92 stored in the NVRAM 106 is cleared without counting up the number of detections (S7) (S8).
After clearing the ON measurement time of the optical sensor 92 (S8), the process returns to Step 3 where it is determined whether or not the glass turning operation is finished again. If the glass turning operation is not finished (S3: NO) ), The process of each step described above is executed.

When the mounted developing cartridge 30 is an old developing cartridge during the glass turning operation, as shown in FIG. 9, the number of times the photosensor 92 is turned on / off is 0 times. Therefore, the count-up of the number of detections (S7) is not performed once, and the glass-turning operation is ended in the state where the number of detections is “0”.
In addition, when the mounted developing cartridge 30 is a new high-capacity developing cartridge during the rotation operation, since one contact protrusion 82 is provided, as shown in FIG. The number of on / off detections of the optical sensor 92 is one. For this reason, the detection count is incremented once (S7), and the counting operation is terminated in a state where the detection count is “1”.

  In addition, when the mounted developing cartridge 30 is a new low-capacity developing cartridge during the loosening operation, two contact protrusions 82 are provided, and as shown in FIG. The number of on / off detections of the optical sensor 92 is two. For this reason, the detection count is incremented twice (S7), and the glass turning operation is terminated in a state where the detection count is “2”.

  When the glass turning operation ends (S3: YES), it is first determined whether or not the optical sensor 92 is turned on (S9). When the optical sensor 92 is turned on (S9: YES), for example, when the contact protrusion 82 and the contact claw 95 remain in contact with each other, the number of detections is normal. Not counted. Therefore, in such a case, it is determined that the new article determination process is an error (S10), and the process returns to the main routine (not shown). If it is determined that the new article determination process is an error, the error is displayed on an operation panel (not shown).

  On the other hand, when the optical sensor 92 is turned off (S9: NO), it is determined that the number of detections is normally counted, and it is determined whether or not the detection number count is “0” (S11). If the detection count is “0” (S11: YES), it is determined that the developing cartridge is an old product (S12), and the process returns to the main routine (not shown). If it is determined that the developing cartridge is an old product, as described above, the maximum number of image formations when it is determined to be new and the actual number of image formations on the paper 3 from when it is determined that it is new. The comparison continues.

  Subsequently, when the detection frequency count is not “0” (S11: NO), it is determined whether or not the detection frequency count is “1” (S13), and when the detection frequency count is “1” (S13). S13: YES), the table 107 stored in the ROM 104 is referred to, and based on the “high capacity” associated with the detection count “1”, it is determined that the cartridge is a new high capacity developing cartridge. (S14), the process returns to the main routine (not shown). If it is determined that the cartridge is a new high-capacity developing cartridge, the CPU 90 determines that the developing cartridge 30 is new and the maximum number of images formed on the developing cartridge 30 is 6000, as described above. A toner empty warning is displayed on an operation panel or the like (not shown) until the actual number of formed images detected by the paper discharge sensor 60 exceeds 6000 from when the developing cartridge 30 is mounted.

  Subsequently, when the detection frequency count is not “1” (S13: NO), it is determined whether the detection frequency count is “2” (S15), and when the detection frequency count is “2” (S15). In step S15: YES, the table 107 stored in the ROM 104 is referred to, and based on the “low capacity” associated with the detection count “2”, it is determined that the cartridge is a new low capacity developing cartridge. (S16), the process returns to the main routine (not shown). If it is determined that the cartridge is a new low-capacity developing cartridge, the CPU 90 determines that the developing cartridge 30 is new and the maximum number of images formed on the developing cartridge 30 is 3000, as described above. A determination is made that a toner empty warning is displayed on an operation panel (not shown) from when the developing cartridge 30 is mounted until the actual number of formed images detected by the paper discharge sensor 60 exceeds 3000.

  On the other hand, when the number of detection times is not “2” (S15: NO), that is, when the number of detection times is “3” or more, the number of times of detection in the table 107 stored in the ROM 104 does not exist. In this case, it is determined that the capacity is high, and it is determined that the cartridge is a new high capacity developing cartridge (S14), and the process returns to a main routine (not shown). When it is determined that the cartridge is a new high-capacity developing cartridge, the CPU 90 determines that the developing cartridge 30 is new and the maximum number of images to be formed on the developing cartridge 30 is 6000, as described above. A toner empty warning is displayed on an operation panel or the like (not shown) until the actual number of formed images detected by the paper discharge sensor 60 exceeds 6000 from when the developing cartridge 30 is mounted.

  In such a new article determination process, as the number of the contact protrusions 82 increases, the number of times the photosensor 92 is turned on / off increases. Even if a light reception signal is input, the light reception signal may be overlooked, and the number of detections may be determined to be smaller than the actual number of on / off detections. For this reason, when two contact protrusions 82 are provided, the CPU 90 detects that the light sensor 92 has overlooked the light sensor 92 and the number of times the optical sensor 92 is detected as ON / OFF is actually two times. May be misjudged.

  For example, if two contact projections 82 are provided corresponding to the high-capacity developer cartridge, the optical sensor 92 is actually turned on / off due to oversight of the light reception signal by the CPU 90 as described above. If the number of times of detection should be determined as two, but if it is erroneously determined as one, the CPU 90 determines that the maximum number of images to be formed on the high-capacity developing cartridge is 3,000, even though it is 6000. .

  Then, the CPU 90 displays a toner empty warning on an operation panel (not shown) or the like immediately after the actual number of formed images detected by the paper discharge sensor 60 exceeds 3000 after the developing cartridge 30 is mounted. Since the arrival of the replacement time is notified, there is a problem that the developing cartridge 30 is replaced while the toner remaining in a large amount in the high-capacity developing cartridge is not consumed.

  On the other hand, according to the new article determination process, since one contact protrusion 82 is provided corresponding to the high-capacity developing cartridge, as described above, the light emitted by the CPU 90 is higher than that in the case where two contact protrusions 82 are provided. The possibility of erroneous determination of the number of times the sensor 92 is turned on / off can be reduced. For this reason, it is possible to prevent the above-described problem, that is, the problem that the developing cartridge 30 is replaced without consuming a large amount of toner remaining in the high-capacity developing cartridge.

In this new article determination process, two abutment projections 82 are provided corresponding to the low-capacity developing cartridge, so that the CPU 90 causes the CPU 90 to detect the maximum image of the low-capacity developing cartridge by overlooking the light reception signal. Even though the number of sheets formed is 3,000, there is a possibility that it is determined as 6000.
However, in the laser printer 1, as described above, since the actual remaining amount of toner stored in the toner storage chamber 41 is determined by the toner empty sensor, the actual remaining amount of toner becomes small. By the determination of the toner empty sensor, a toner empty warning is displayed on an operation panel (not shown). Therefore, even if the maximum image forming number of the low-capacity developing cartridge is erroneously determined to be 6000 sheets, a toner empty warning is displayed based on the actual number of image forming sheets detected by the paper discharge sensor 60 until it exceeds 3000 sheets. Even if it is not performed, the toner empty warning is displayed based on the determination of the toner empty sensor, so that such a problem does not occur.

  In this new article determination process, if the detection count is not “2” in step 15 (S15: NO), that is, the detection corresponding to the detection count other than the detection count associated with the table 107 of the ROM 104 is detected. If the count is the number of times, it is determined as “high capacity” in step 14, and the CPU 90 determines that the cartridge is a new high capacity developing cartridge. Therefore, even if the noise signal input to the CPU 90 is erroneously determined as a light reception signal, the detection count corresponding to the detection count other than the detection count associated with the table 107 is “high capacity”. Thus, it is possible to prevent such a problem that the developing cartridge 30 is replaced while the toner remaining in a large amount in the high-capacity developing cartridge is not consumed.

  In the above description, if the detection count is not “2” in step 15 (S15: NO), that is, the detection count corresponding to the detection count other than the detection count associated with the table 107 of the ROM 104. If it is a count, it is determined as “high capacity” (S14). For example, as shown in FIG. 11, it is determined that the new article determination process is an error without determining “high capacity” ( S17), the process may return to a main routine (not shown). If it is determined that the new article determination process is an error, the error is displayed on an operation panel (not shown).

The flowchart shown in FIG. 11 includes the same steps as the flowchart shown in FIG. 10 except for the above description.
In the above description, the motor 59 is driven to rotate at the full speed that is the rotation speed at the time of image formation during the detection operation in which the passage of the contact protrusion 82 is detected by the optical sensor 92, that is, during the rotation operation. However, for example, during the rotation operation, the motor 59 is decelerated from the rotational speed at the time of image formation, and is driven to rotate at a half speed, for example, half the full speed, thereby detecting the on / off of the optical sensor 92. It is also possible to improve the accuracy of determination of the number of times in the CPU 90.

FIG. 12 is a flowchart showing the motor rotation speed determination process in the glass turning operation performed by the CPU 90. This process is performed as the process of step 2a in FIG.
This motor rotation speed determination processing is stored as a motor rotation speed determination processing program in the ROM 104 in order to drive the motor 59 to rotate at half speed during the rotation operation.

As shown in FIG. 12, in this motor rotation speed determination process, first, it is determined whether or not there is an instruction to rotate the motor 59 for an image forming operation or a gear rotation operation (S31). If there is no instruction to rotate the motor 59 (S31: NO), the process returns to the main routine (not shown) and the determination in step 31 is continued.
If there is an instruction to rotate the motor 59 (S31: YES), it is determined whether the power is turned on or whether a closing detection signal is input to the CPU 90 (S32). When neither the power is turned on nor the closing detection signal is input to the CPU 90 (S32: NO), the motor 59 is rotated in the image forming operation. In such a case, the motor 59 is rotated at full speed (S33), and the process returns to the main routine (not shown).

On the other hand, when either the power is turned on or the closing detection signal is input to the CPU 90 (S32: YES), the above-described glass turning operation is started. In such a case, The motor 59 is rotated at half speed (S34), and the process returns to the main routine (not shown).
FIG. 13 is a timing chart of the new article determination process when the motor is driven to rotate at half speed, and FIG. 14 is a flowchart of the new article determination process when the motor is driven to rotate at half speed.

  When the motor 59 is driven to rotate at half speed, as shown in FIG. 13, first, when a new high-capacity developing cartridge is mounted on the main casing 2, a new one as described above is used. When the high-capacity developing cartridge is mounted, the optical sensor 92 is turned on. Under the control of the CPU 90, the motor 59 is driven at half speed, and then the optical sensor 92 is turned off. It should be noted that the time from the start of the rotation operation until the optical sensor 92 is turned off is 0.6 seconds when the motor 59 is driven at half speed.

  Further, when a new low-capacity developing cartridge is mounted on the main casing 2, the optical sensor 92 is turned on when a new low-capacity developing cartridge is mounted, as described above, under the control of the CPU 90. After the motor 59 is driven at half speed, the optical sensor 92 is turned off. It should be noted that the time from the start of the rotation operation until the optical sensor 92 is turned off is 0.6 seconds when the motor 59 is driven at half speed.

Thereafter, the optical sensor 92 is turned on again. Note that the time from when the optical sensor 92 is turned off to when the optical sensor 92 is turned on again is 2.2 seconds (that is, from the start of the rotation operation) when the motor 59 is driven at half speed. The time until the optical sensor 92 is turned on again is 2.8 seconds when the motor 59 is driven at half speed.
Then, the optical sensor 92 is turned off again. Note that the time from when the optical sensor 92 is turned on again to when the optical sensor 92 is turned off is 0.6 seconds (that is, when the motor 59 is driven at half speed). Until the optical sensor 92 is turned off again is 3.4 seconds when the motor 59 is driven at half speed.

When an old developing cartridge is mounted on the main casing 2, as described above, the optical sensor 92 is not turned on but is kept off.
Next, a new article determination process when the motor is driven to rotate at half speed will be described with reference to FIG. In FIG. 14, in this new article determination process, in step 6 of the flowchart shown in FIG. 10 described above, it is substituted for determining whether or not the time during which the optical sensor 92 is on is 0.3 seconds or more. Then, it is determined whether or not the time during which the optical sensor 92 is turned on is 0.6 seconds or more. Except for Step 6, processing similar to the steps of the flowchart shown in FIG. 10 is executed. Is done.

  That is, in this new article determination process, the time during which the optical sensor 92 is turned on increases as the motor is driven to rotate at half speed, and accordingly, the time during which the optical sensor 92 is turned on. If it is 0.6 seconds or longer (S6: YES), it is determined that this is a light reception signal input, the number of detections is counted up (S7), and then the optical sensor 92 stored in the NVRAM 106 is turned on. If the measurement time is cleared (S8) and the optical sensor 92 is on for less than 0.6 seconds (S6: NO), it is determined as a noise signal and the number of detections is counted. The ON measurement time of the optical sensor 92 stored in the NVRAM 106 is cleared without increasing (S7) (S8).

  As described above, when the motor is driven to rotate at half speed in the rotation operation, the optical sensor 92 can detect the passage of the contact protrusion 82 with higher accuracy, and the CPU 90 receives the input from the optical sensor 92. The received light signal can be detected and judged more accurately. As a result, it is possible to reliably determine whether the cartridge is a high capacity developing cartridge or a low capacity cartridge.

  In each of the above embodiments, the developing cartridge 30 is provided separately from the process frame 27 in which the photosensitive drum 28 is disposed. However, the developing cartridge according to the present invention is formed integrally with the process frame 27. Needless to say, it may be one that has been used.

DESCRIPTION OF SYMBOLS 1 Laser printer 2 Main body casing 30 Developing cartridge 59 Motor 69 Agitator drive gear 70 Detection gear 80 Tooth part 81 Chip part 82 Contact protrusion 85 Coil spring 89 Information detection mechanism part 90 CPU
91 Actuator 92 Optical sensor 104 ROM
107 tables

Claims (20)

An image forming apparatus main body;
A developer cartridge that is detachable from the image forming apparatus main body and contains a developer;
Driving means provided in the image forming apparatus main body;
A driving member provided in the developing cartridge, which can be driven by the driving means when the developing cartridge is attached to the image forming apparatus main body, and is driven by a predetermined driving amount from a driving start to a driving stop;
A movable member movable with the drive of the drive member;
Detecting means for allowing the moving member to move by driving the driving member, and detecting the passage of the moving member;
An image forming apparatus comprising: an information determining unit that determines information about the developing cartridge based on a result of detection of the moving member by the detecting unit. The detection means includes a contact member that contacts the moving member,
The image forming apparatus according to claim 1, wherein a contact direction in which the moving member contacts the contact member and a moving direction of the moving member are the same direction.   The image forming apparatus according to claim 2, wherein the abutting member abuts on the moving member when the developing cartridge is mounted on the image forming apparatus main body.   The drive member is a missing tooth gear in which a tooth portion to which a driving force from the driving means is transmitted and a missing tooth portion to which a driving force from the driving means is not transmitted are formed. Item 4. The image forming apparatus according to any one of Items 1 to 3. The developing cartridge includes a transmission gear to which driving force from the driving unit is transmitted when the developing cartridge is mounted on the image forming apparatus main body.
The image forming apparatus according to claim 4, wherein the chipped gear is meshed with the transmission gear.   The image forming apparatus according to claim 5, wherein the developing cartridge includes a biasing unit that biases the chipped gear toward the transmission gear so that the gears mesh with each other.   The image forming apparatus according to claim 1, wherein a plurality of the moving members are provided. The number of the moving members corresponds to information on the developing cartridge,
The image forming apparatus according to claim 1, wherein the information determination unit determines information related to the developing cartridge based on the number of detections of the moving member by the detection unit. The moving member has a width along the moving direction corresponding to information on the developing cartridge,
The image forming apparatus according to claim 1, wherein the information determination unit determines information about the developing cartridge based on the detection time by the detection unit.   10. The image forming apparatus according to claim 1, wherein the information on the developing cartridge is information on whether or not the developing cartridge is new.   10. The image according to claim 1, wherein the information on the developing cartridge is information on a maximum number of recording media on which an image can be formed with a developer contained in the developing cartridge. Forming equipment. In the developing cartridge that is detachable from the image forming apparatus main body and contains the developer,
A driving member that can be driven by a driving means provided in the image forming apparatus main body when the developing cartridge is mounted in the image forming apparatus main body, and that is driven by a predetermined driving amount from a driving start to a driving stop;
A developing cartridge, comprising: a moving member that is movable along with the driving of the driving member and is capable of passing through a detection position detected by a detecting unit provided in the main body of the image forming apparatus.   The drive member is a missing tooth gear in which a tooth portion to which a driving force from the driving means is transmitted and a missing tooth portion to which a driving force from the driving means is not transmitted are formed. Item 13. The developing cartridge according to Item 12. In the developing cartridge that is detachable from the image forming apparatus main body and contains the developer,
When the developing cartridge is mounted on the image forming apparatus main body, the driving unit provided in the image forming apparatus main body can be driven, and a tooth portion to which the driving force from the driving means is transmitted, and the driving A chipped tooth portion that is not transmitted with the driving force from the means, and is driven at a predetermined drive amount from the start of driving to the stop of driving; and
A developing cartridge comprising: a moving member that is movable along with the driving of the chipped gear and is provided to face the middle of the tooth portion in the rotation direction of the chipped gear. A transmission gear for transmitting a driving force from the driving means when the developing cartridge is mounted on the image forming apparatus main body;
The developing cartridge according to claim 13 or 14, wherein the chipped gear is meshed with the transmission gear.   16. The developing cartridge according to claim 15, further comprising urging means that urges the chipped gear toward the transmission gear so that the gears mesh with each other.   The developing cartridge according to claim 12, wherein a plurality of the moving members are provided. An image forming apparatus main body;
A developer cartridge that is detachable from the image forming apparatus main body and contains a developer;
Driving means provided in the image forming apparatus main body;
A driving member provided in the developing cartridge, which can be driven by the driving means when the developing cartridge is attached to the image forming apparatus main body, and is driven by a predetermined driving amount from a driving start to a driving stop;
A movable member movable with the drive of the drive member;
The moving member that moves by the driving of the driving member can be passed, and the transfer is possible.
Detection means for detecting passage of the moving member;
Information determining means for determining information relating to the developing cartridge based on the detection result of the moving member by the detecting means;
When the amount of developer accommodated in the developing cartridge is the first amount, the moving member is provided in a first number and is a second amount smaller than the first amount. Are provided in a second number greater than the first number,
The information determination means is a developer stored in the developer cartridge when the number of detections detected by the detection means based on the passage of the moving member is the number of detections corresponding to the first number. When it is determined that the amount is the first amount and the number of times of detection corresponds to the second number, it is determined that the amount of developer stored in the developing cartridge is the second amount. An image forming apparatus. The first amount and the second amount are associated with the number of detections of the detection unit corresponding to the first number and the number of detections of the detection unit corresponding to the second number, respectively. A storage means for storing the table;
The information determination means refers to the storage means, and when the detected number of detections is a number of detections other than the number of detections associated with the table, the developer contained in the developer cartridge The image forming apparatus according to claim 18, wherein the amount is determined to be a first amount.   20. The drive unit according to claim 18, wherein the driving unit decelerates the moving speed of the moving member during the detecting operation of the moving member by the detecting unit as compared with the time of image formation for image formation. The image forming apparatus described.

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