JP2008254881A - Device for counting the number of paper sheet for paper feeding cassette - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a device for counting the number of paper sheets for a paper feeding cassette capable of accurately counting the number of remaining paper sheets even when the thickness of one paper sheet varies. <P>SOLUTION: This device for counting the number of paper sheets for the paper feeding cassette comprises a counting fixed claw piece 312 for applying elasticity to the paper sheet end of each of paper sheets shifted one by one; a counting movable claw piece 311 flipped by paper sheets released from the elasticity applied by the counting fixed claw piece 312; a counting movable claw piece fulcrum 135 for rotating the counting movable claw piece 311 at the center; and a photosensor unit 317 through which part of the counting movable claw piece 311 passes along with the flipping operation by paper sheets. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a paper feed cassette used in an image forming apparatus such as a facsimile, a printer, and a copying machine, and more particularly to a configuration that accurately detects the remaining amount of sheets such as paper in the paper feed cassette.

  2. Description of the Related Art Conventionally, in an image forming apparatus such as a facsimile, a printer, and a copying machine, a sheet cassette in which sheet-like sheets are stored in a bundle is set in the apparatus body, and the sheet bundle is formed by a sheet feed roller provided in the apparatus body. A configuration in which paper is fed from the uppermost sheet toward the image forming unit in the apparatus main body is often used.

  In this paper feed cassette, there are a dedicated cassette corresponding to a specific paper type and a cassette capable of dealing with a plurality of types of paper, and the operator is notified of the paper replenishment timing regardless of which cassette is used. There is a need. For this reason, a mechanism for counting the number of sheets loaded on the cassette is provided around the sheet feeding cassette.

As such a mechanism, for example, in Patent Document 1 (Japanese Patent Laid-Open No. 8-91627), in a paper supply device provided with a paper delivery means for delivering paper from a paper storage cassette, the paper is loaded on the paper storage cassette. A rotating body that contacts the uppermost surface of the sheet and rotates as the sheet is fed by the sheet feeding means, a support mechanism that supports the rotating body so as to be movable in the sheet stacking direction, and a support mechanism that supports the rotating body. A stopper for limiting the moving range of the rotating body, a rotation detecting means for detecting the rotation of the rotating body, a control means for determining the remaining amount of paper based on the output of the rotation detecting means and performing a corresponding process Are described.
JP-A-8-91627

  The conventional sheet remaining amount detection device in the cassette is as described above. However, the information that the user of the image forming apparatus such as a printer really wants to know is not an estimate of the remaining sheet amount, but “how many sheets can be printed? In general, it is the remaining number of sheets. However, the amount of paper that can be set in the printer (or paper cassette) varies, and the thickness of the paper itself also varies depending on the type of paper. Therefore, even if the remaining amount of paper is roughly indicated, the printer user cannot grasp the remaining number of sheets.

  Similar problems exist not only in printers but also in similar devices having a mechanism for measuring and displaying the number of sheets in some form. That is, even if you try to count the current number of remaining sheets, the thickness of one sheet varies depending on whether the loaded sheet is a cut sheet or an envelope. I couldn't.

  Therefore, an object of the present invention is to provide a technique for accurately displaying the remaining number of sheets even in a case where the thickness of the sheets is different in an apparatus having a mechanism for measuring the number of sheets. It is to provide.

  In order to solve the above-mentioned problems, the present invention is free from the fixed claw piece for counting which gives elasticity to the paper edge of the sheet shifted by one sheet, and the elasticity given by the fixed claw piece for counting. The counting movable claw piece repelled by the paper sheet, the counting movable claw piece fulcrum for rotating the counting movable claw piece about the center thereof, and one of the counting movable claw pieces as the sheet is repelled by the movement. It is a sheet number counting device of a sheet feeding cassette characterized by comprising a photo sensor unit through which a section passes.

  In the sheet cassette counting device of the sheet feeding cassette of the present invention, the counting movable claw piece is provided with a notch from the upper side to the lower side.

  In the sheet cassette counting device of the sheet feeding cassette according to the present invention, the counting claw piece is provided with a notch from the lower side to the upper side.

  In the sheet counting device of the sheet feeding cassette according to the present invention, a part of the counting movable claw piece that passes through the photo sensor unit is different from a side on which the counting movable claw piece is repelled by the sheet. It is the side of this.

  Further, the sheet number counting device of the sheet feeding cassette of the present invention includes the counting fixed claw piece, the counting movable claw piece, the counting movable claw piece fulcrum, and the photo sensor unit as a sheet number counting unit. It is characterized by being unitized.

  Further, the sheet number counting device of the sheet feeding cassette according to the present invention is characterized in that the sheet number counting unit performs scanning in the direction of shifting the sheet edge of the sheet shifted by one sheet.

  According to the sheet count device of the sheet cassette of the present invention, it is possible to accurately count the remaining number of sheets even if the thickness of one sheet is different.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings, taking as an example the case where the image forming apparatus is a color printer. FIG. 1 is a configuration diagram (main part sectional view) of an image forming apparatus (color printer 2) on which a sheet number counting device for a sheet feeding cassette according to an embodiment of the present invention is mounted. In FIG. 1, 621 is a photosensitive drum, 622 is a charging unit, 623 is an exposure unit, 611B is a black toner cartridge, 611M is a magenta toner cartridge, 611C is a cyan toner cartridge, 611Y is a yellow toner cartridge, and 614B to 614Y are mounting portions. , 626 is a primary transfer unit, 627 is an intermediate transfer member, 71 is an operation display panel, 200 is a paper feed cassette, 94 is a paper feed roller, 100 is a dust cover member feed mechanism, 628 is a secondary transfer unit, and 629 is a fixing unit. Respectively. The engine of the color printer 2 is composed of a charging unit, an exposure unit, a developing device, a transfer unit, and the like, but in FIG. 1, it is expressed by a classification of a developing device 61 (developing means) and other in-engine units 62. Yes.

  The photosensitive drum 621 has a cylindrical conductive substrate and a photosensitive layer formed on the outer peripheral surface thereof, is rotatable with respect to the central axis, and rotates counterclockwise as indicated by an arrow. The charging unit 622 charges the photosensitive drum 621, and the exposure unit 623 irradiates the charged photosensitive drum 621 with a beam from a light source such as a built-in laser or LED array to form a latent image due to static electricity. Beam irradiation of the exposure unit 623 is controlled by, for example, a drive signal modulated based on image information input from a host computer (not shown).

  The developing device 61 includes mounting portions 614B to 614Y on which a black toner cartridge 611B, a magenta toner cartridge 611M, a cyan toner cartridge 611C, and a yellow toner cartridge 611Y that store toner as developer are detachably mounted. A developing rotary that is rotatable with respect to 613. The developing device 61 is rotated to bring the necessary toner cartridges 611B to 611Y close to the photosensitive drum 621, and the developing material is supplied to the photosensitive drum 621 on which the latent image is formed, so that the latent image becomes an image by the developing material. Developed.

  The primary transfer unit 626 transfers the toner image formed on the photoconductor 621 to the intermediate transfer body 627. The intermediate transfer member 627 is an endless belt in which an aluminum vapor deposition layer is formed on the surface of a PET film and a semiconductive paint is formed on the surface, for example, and is driven to rotate at the same peripheral speed as that of the photosensitive drum 621. A sheet material such as paper supplied from the paper feed cassette 200 is conveyed to a secondary transfer unit 628 and a fixing unit 629 through a paper feed roller 94. Then, the secondary transfer unit 628 transfers the toner image formed on the intermediate transfer body 627 to the sheet material supplied from the paper feed cassette 92, and the fixing unit 629 transfers the toner image transferred onto the print medium to the medium. To form a permanent image, and the print medium is discharged out of the printer 2.

  The cleaning unit 624 is provided between the primary transfer unit 626 and the charging unit 622 and has a cleaning blade 625 that comes into contact with the surface of the photosensitive drum 621 and remains on the photosensitive drum 621 after the primary transfer. The developing material (toner) to be removed is removed by the cleaning blade 625.

  In the present invention, the paper feed cassette 200 includes a paper number counting unit that accurately counts the number of paper sheets when the number of loaded paper sheets in the paper feed cassette 200 is near empty (approximately several tens of sheets). is there.

  The sheet cassette loading thickness detection sensor 400 is a sensor for detecting the thickness of the sheet loaded in the sheet feeding cassette 200, and the number of sheets loaded in the sheet feeding cassette 200 by the sheet feeding cassette loading thickness detection sensor 400. Estimate. In such a paper cassette loading thickness detection sensor 400, the thickness of the total number of sheets loaded is detected, the number of sheets loaded is estimated from the thickness, and the number of sheets used is subtracted therefrom. This is used in the near empty detection unit 503 described later. The reason why the sheet cassette loading thickness detection sensor 400 cannot calculate the exact number of sheets is because the sheet thickness differs depending on the type of sheet.

  Specific configurations of the sheet cassette loading thickness detection sensor 400 include, for example, a mechanical type and an optical type. In the former, for example, a manipulator is fed out from a sensor and brought into contact with the uppermost sheet surface to detect the thickness of the loaded sheet. In the latter case, for example, the thickness of the loaded paper is detected using the reflected light when the light emitted from the light emitting element of the paper feed cassette loading thickness detection sensor 400 is reflected from the uppermost paper surface. For this, the technique described in Japanese Patent Application Laid-Open No. 2001-114451 can be used.

  The operation means of the apparatus front surface information section is a part for the user to operate the color printer 2, and includes an operation display panel 71, operation buttons, and the like. A device such as a touch panel is provided on the operation display panel 71, and the user touches the operation display panel 71 directly while referring to a UI (user interface) displayed on the operation display panel 71. The printer 2 can be operated. In the operation unit, various setting actions such as setting of printing conditions in the color printer 2 are possible. The color printer 2 according to the present embodiment is configured such that the paper feed cassette 200 is attached from the front side of the apparatus where the operation display panel 71 as an operation means is located.

  Next, the structure of the paper feed cassette 200 in the embodiment of the present invention will be described. FIG. 2 is a perspective view of the paper stacking plate of the paper feed cassette 200 according to the embodiment of the present invention. In FIG. 2, 240 is a paper stacking portion, 250 is a bottom plate of the paper stacking portion, 251 and 252 are notched recesses, 253, 254 and 255 are long hole convex portions, 256, 257 and 258 are long holes, and 259 is a first hole. Projection pieces, 260 is a sheet stacking portion side plate, 261 and 262 are engaging projections, 265 is a second projection piece, and 270 is a shaft.

  The sheet stacking unit 240 includes a sheet stacking unit bottom plate 250 that stacks schematic sheets directly above, and a sheet stacking unit side plate 260 that supports sheets from the side. The sheet stacking portion bottom plate 250 is provided with cutout recesses 251 and 252 at two locations as shown on one side thereof. Locations other than the cutout recesses 251 and 252 are long hole convex portions 253, 254, and 255, and long holes 256, 257, and 258 are formed in the long hole convex portions, respectively.

  The paper stacking portion side plate 260 is provided with engaging convex portions 261 and 262, and the engaging convex portion is provided with a hole penetrating the engaging convex portion. The shaft 270 includes a long hole 256 in the long hole convex portion 253, a through hole in the engaging convex portion 261, a long hole 257 in the long hole convex portion 254, a through hole in the engaging convex portion 262, and a long hole convex portion 255. The engaging projections 261 and 262 are slidable in the range of the long holes 256, 257, and 258 by such a configuration.

  First protrusion pieces 259 are provided on the side surface portions on both sides of the sheet stacking portion bottom plate 250. In addition, second protrusion pieces 265 are provided on the side surface portions on both sides of the sheet stacking portion side plate 260. Of the first and second protrusions 259 and 265 provided on both sides, only one is shown.

Next, the guide side plate through which the first protrusion piece 259 and the second protrusion piece 265 penetrate will be described. FIG. 3 is a diagram showing a guide side plate of the paper feed cassette 200 in the embodiment of the present invention. What is shown in FIG. 3A is a second guide side plate 272. The second guide side plate 272 includes
A second guiding long hole 274 is provided, and the second guiding long hole 274 is used so that the second protruding piece 265 formed on the sheet stacking portion side plate 260 penetrates. What is shown in FIG. 3B is a first guide side plate 271. The first guide side plate 271 is provided with a first guide slot 273, and the first guide piece 259 formed on the sheet stacking portion bottom plate 250 penetrates into the first guide slot 273. It is used in this way.

  Of the second guide slot 274 provided in the second guide side plate 272, the portion indicated by P1 is a guide profile for the normal printing operation of the color printer 2, and the portion indicated by P2 is 4 is a guide profile for the operation of counting the number of sheets of the color printer 2.

  Of the first guide slot 27 provided in the first guide side plate 271, the portion indicated by P3 is a guide profile for the normal printing operation of the color printer 2, and the portion indicated by P4 is 4 is a guide profile for the operation of counting the number of sheets of the color printer 2. A part of the guide profile P4 has a wave-like portion as shown in the figure, and the sheet stacking portion bottom plate 250 vibrates when the first protrusion piece 259 passes through the guide profile P4.

  The sheet cassette 200 equipped with the sheet stacking unit 240, the first guide side plate 271 and the second guide side plate 272 as described above will be described. FIG. 4 is a diagram showing the configuration of the paper feed cassette 200 in the embodiment of the present invention.

  In FIG. 4, 201 is a paper cassette box-shaped portion, 202 is an intermediate partition plate, 210 is a first actuator, 211 is a second actuator, 212 is a first operation rod, 213 is a second operation rod, and 300 is a sheet count. Each part is shown.

  The sheet feeding cassette box-shaped portion 201 is provided with an intermediate partition plate 202 for partitioning the upper portion and the lower portion. The upper portion partitioned by the intermediate partition plate 202 has a sheet stacking portion 240 and a first guide side plate 271. The second guide side plate 272 and the sheet number counting unit 300 are disposed, and a first actuator 210 and a second actuator 211 are disposed in a lower portion partitioned by the intermediate partition plate 202.

  The first guide side plate 271 and the second guide side plate 272 are fixed to the upper side wall partitioned by the intermediate partition plate 202 so that the paper stacking unit 240 is movable. A first operating rod 212 and a second operating rod 213 extend from the first actuator 210 and the second actuator 211 provided in the lower part partitioned by the intermediate partition plate 202, respectively, and the paper stacking of the paper stacking unit 240 is performed. The bottom plate 250 is supported.

  In the present embodiment, a mechanism for supporting and moving the sheet stacking portion bottom plate 250 by the first operating rod 212 extending from the first actuator 210 and the second operating rod 213 extending from the second actuator 211. However, the mechanism for supporting and moving the sheet stacking portion bottom plate 250 may have other configurations. For example, a mechanism for supporting and moving the sheet stacking unit bottom plate 250 by a motor, a reel that rotates in conjunction with the rotation of the motor, and a suspension line drawn from the reel may be used. In this case, the paper stacking unit bottom plate 250 is suspended from the upper side by the hanging line. In any case, in the present invention, the sheet stacking portion bottom plate 250 is supported at at least two locations and is movable at the support points.

  Next, a usage pattern of the paper feed cassette 200 configured as described above will be described with reference to FIGS. 5 to 6 show a state when the paper feed cassette 200 according to the embodiment of the present invention is mounted on the color printer 2.

  FIG. 5 is a diagram illustrating a form when the sheet cassette 200 according to the embodiment of the present invention approximates the number of sheets by the sheet cassette loading thickness detection sensor 400. When the sheet cassette loading thickness detection sensor 400 estimates the number of sheets, the first operating rod 212 of the first actuator 210 and the second operating rod 213 of the second actuator 211 take positions as shown in the figure, The bottom plate 250 is pushed up to the top. When the detection mechanism of the sheet cassette loading thickness detection sensor 400 is, for example, a mechanical type, the manipulator 401 is extended from the sensor 400 and brought into contact with the uppermost sheet surface, so that the thickness of the loaded sheet is Is detected.

  FIG. 6 is a diagram showing a form when the paper feed cassette 200 feeds the color printer 2 in the embodiment of the present invention. When the paper feed cassette 200 feeds the color printer 2, the first operating rod 212 of the first actuator 210 and the second operating rod 213 of the second actuator 211 take the positions shown in the figure, and the paper stacking unit The bottom plate 250 is inclined to smoothly feed the image from the sheet feed roller 94 to the image forming process.

  FIG. 7 is a diagram illustrating a form when the paper feed cassette 200 according to the embodiment of the present invention counts the number of sheets by the sheet number counting unit 300. When the paper feed cassette 200 counts the number of sheets by the sheet number counting unit 300, the first operation rod 212 of the first actuator 210 and the second operation rod 213 of the second actuator 211 take positions as shown. The sheet stacking unit bottom plate 250 is inclined while the sheet stacking unit side plate 260 is slightly laid down. With this configuration, the sheets on the sheet stacking unit bottom plate 250 are shifted one by one in accordance with the inclination angle of the sheet stacking unit side plate 260, and the sheet number counting unit 300 described in detail later. This makes it easier to count the number of paper sheets.

  When the sheet cassette 200 counts the number of sheets by the sheet number counting unit 300, the sheet cassette 200 is changed from the form shown in FIG. 6 to the form shown in FIG. However, the sheet stacking portion bottom plate 250 vibrates by passing through the wavy portion of the guide profile P4 in the first guide slot 27 of the first guide side plate 271. Due to such vibration, the sheets on the sheet stacking portion bottom plate 250 are easily shifted one by one. In order to shift the sheets one by one, in this embodiment, the wavy portion of the guide profile P4 is used to cause the paper stacking portion bottom plate 250 to vibrate. An eccentric cam linked to the movement may be provided, and the sheet stacking unit bottom plate 250 may be struck by the eccentric cam to cause the sheet stacking unit bottom plate 250 to vibrate. Further, a vibrator or the like may be provided on the paper stacking unit bottom plate 250, and this may be vibrated to vibrate the paper stacking unit bottom plate 250.

  Next, the sheet number counting unit 300 will be described. FIG. 8 is a diagram illustrating the sheet number counting unit 300 of the sheet feeding cassette 200 according to the embodiment of the present invention. FIG. 8 is an enlarged view showing an R portion of FIG. In FIG. 8, reference numeral 310 denotes a sheet number counting unit, 311 denotes a counting movable claw piece, 312 denotes a counting fixed claw piece, 315 denotes a counting movable claw piece fulcrum, and 317 denotes a photosensor unit. The sheet number counting unit 310 is provided with a counting claw piece and a photo sensor unit, and is moved in a direction indicated by D in the drawing by a mechanism (not shown). Along with such movement, the claw piece for counting the number of sheets is shaped to scan the end of the sheet.

  The counting claw piece 312 is fixed with respect to the sheet number counting unit 310 and gives elasticity to the sheet underneath. The sheet provided with elasticity by the counting fixed claw piece 312 is then released from the counting fixed claw piece 312 and repels the counting movable claw piece 311. FIG. 9 is a diagram illustrating the movement of the counting movable claw piece 311 of the sheet number counting unit 300 according to the embodiment of the present invention. The counting movable claw piece 311 is configured to rotate around the counting movable claw piece fulcrum 315. The counting movable claw piece 311 is provided with a cut portion 321 from the upper side portion to the lower side portion, and the counting fixed claw piece 312 is provided with a cut portion 322 from the lower side portion to the upper side portion. By forming these notches 321 and 322, it is possible to smoothly apply elasticity to the paper and release it.

  The counting movable claw piece 311 repelled by the sheet moves like a seesaw around the counting movable claw piece fulcrum 315 as shown in FIG. At this time, the movable counting claw piece 311 passes through the photo sensor unit 317 including the light emitting unit and the light receiving unit. The sheet number counting unit 300 detects the light shielding of the counting movable claw piece 311 of the photo sensor unit 317 and counts the number of sheets. Thus, a part of the counting movable claw piece 311 passing through the photosensor unit 317 is substantially the same as the counting movable claw piece fulcrum 315 as the center from which the counting movable claw piece 311 is repelled by the paper. It is a point-symmetrical position.

  As described above, according to the present invention, the counting fixed claw piece 312, the counting movable claw piece 311, the counting movable claw piece fulcrum 315, and the photo sensor unit 317 are unitized as a sheet number counting unit 310, and each sheet is counted as one unit. The sheet number counting unit 310 is configured to scan in the D direction in the direction of deviation of the sheet edge of the shifted sheet.

  Next, a method for processing the detection result from the sheet number counting unit 300 configured as described above will be described. FIG. 10 is a diagram showing a block configuration related to the sheet number counting unit 300 in the embodiment of the present invention. In FIG. 10, reference numeral 501 denotes a control unit, 502 denotes an engine controller unit, 503 denotes a near empty detection unit, and 505 denotes a counter.

  The control unit 501 is a general-purpose information processing mechanism that assumes a main CPU of the color printer 2, a RAM around the CPU, a ROM, and the like. The engine controller unit 502 is a controller that controls the image processing process, and the control unit 501 can obtain information such as “one image forming process is completed” from the engine controller unit 502. The near empty detection unit 503 detects the near empty state of the paper feed cassette 200 by the paper feed cassette loading thickness detection sensor 400 and subtraction therefrom. Note that the near empty state of the paper feed cassette 200 assumes several tens of sheets. The counter 505 is a memory unit for storing the count result obtained by the sheet number counting unit 300. The operation display panel 71 is a display output interface for the user.

  Processing and operation at the time of near empty detection by the block configuration related to the sheet number counting unit 300 as described above will be described. FIG. 11 is a diagram showing a flowchart of processing when near empty is detected in the embodiment of the present invention. Processing according to such a flowchart is realized by the control unit 501 cooperating with a related mechanism based on a predetermined program.

  In FIG. 11, when the near-empty detection start process is started in step S100, the near-empty detection unit 503 determines whether or not a near-empty has been detected in the subsequent step S101. If the determination result is NO, step S101 is looped. When the determination result of step S101 is YES, the process proceeds to step S102.

  In step S102, the sheet number counting unit 300 performs a sheet number counting process. When such a sheet count process is performed, the usage form of the paper feed cassette 200 is changed from that shown in FIG. 6 to that shown in FIG.

  In step S 103, the number of sheets counted by the sheet number counting unit 300 is set as the C value of the counter 505. In the next step S104, the value of the counter C is displayed on the operation display panel 71, thereby notifying the user of the exact remaining number of sheets. Thus, according to the present invention, it is possible to accurately count the remaining number of sheets even if the thickness of one sheet is different.

  In the subsequent step S105, it is determined whether or not one sheet has been used with reference to information from the engine controller unit 502. If the determination result of step S105 is YES, the process proceeds to step S108, and if the determination result of step S105 is NO, the process proceeds to step S106.

  In step S108, which proceeds when the determination result in step S105 is YES, the counter value is decremented by one. After step 108, the process proceeds to step 109. In step S109, it is determined whether C = 0. If the determination result in step S109 is NO, the process proceeds to step S103, and if the determination result in step S109 is YES, the process proceeds to step S110. In step S110, the operation display panel 71 displays that the paper in the paper cassette 200 is empty. Subsequent to step S110, the process proceeds to step S111, and the near empty detection time process is terminated.

  In step S106, which proceeds when the result of determination in step S105 is NO, it is detected whether the paper feed cassette 200 has been removed from the color printer 2. For such detection, conventionally known detection methods can be used as appropriate.

  If the determination result in step S106 is YES, the process proceeds to step S107, and if the determination result in step S106 is NO, the process proceeds to step S105. In step S107, the C value of the counter 505 is reset. Subsequently, the process proceeds to step S111, and the near empty detection time process is terminated.

  As described above, according to the sheet count device of the sheet cassette of the present invention, it is possible to accurately count the remaining number of sheets even if the thickness of one sheet is different.

  The sheet counting device of the sheet cassette of the present invention includes an electrophotographic copying machine, an electrophotographic printer, an electrophotographic facsimile, an electrophotographic multifunction machine, an ink jet copying machine, an ink jet printer, an ink jet facsimile, The present invention can be applied to an image forming apparatus such as an inkjet type multifunction peripheral.

  Further, the present invention includes embodiments configured by arbitrarily combining the components of the respective embodiments.

1 is a configuration diagram (main part sectional view) of an image forming apparatus (color printer 2) on which a sheet number counting device of a sheet feeding cassette according to an embodiment of the present invention is mounted. It is a perspective view of the paper stacking plate of the paper feed cassette 200 in the embodiment of the present invention. It is a figure which shows the guide side board of the paper feed cassette 200 in embodiment of this invention. It is a figure which shows the structure of the paper feed cassette 200 in embodiment of this invention. FIG. 6 is a diagram illustrating a form when the paper feed cassette 200 according to the embodiment of the present invention approximates the number of sheets by a paper feed cassette loading thickness detection sensor 400. FIG. 3 is a diagram showing a form when a paper feed cassette 200 feeds a color printer 2 in an embodiment of the present invention. FIG. 5 is a diagram showing a form when the paper feed cassette 200 in the embodiment of the present invention counts the number of sheets by a sheet number counting unit 300. It is a figure which shows the paper sheet count part 300 of the paper feed cassette 200 in embodiment of this invention. It is a figure which shows the motion of the movable claw piece 311 for a count of the paper sheet count part 300 in embodiment of this invention. It is a figure which shows the block structure relevant to the paper sheet count part 300 in embodiment of this invention. It is a figure which shows the flowchart of the process at the time of near empty detection in embodiment of this invention.

Explanation of symbols

621 ... photosensitive drum, 622 ... charging unit, 623 ... exposure unit, 611B ... black toner cartridge, 611M ... magenta toner cartridge, 611C ... cyan toner cartridge, 611Y ... Yellow toner cartridge, 614B to 614Y, mounting portion, 626, primary transfer unit, 627, intermediate transfer member, 628, secondary transfer unit, 629, fixing unit, 71, operation Display panel 94 ... paper feed roller 100 ... dust cover member feeding mechanism 110 ... dust cover member 111 ... dust cover rack 112 ... dust cover 120 ...・ Pinion part, 200... Paper cassette, 201... Partition plate 210 ... first actuator 211 ... second actuator 212 ... first operation rod 213 ... second operation rod 240 ... paper stacking section 250 ... paper Stacking portion bottom plate, 251, 252... Notched recess, 253, 254, 255, long hole convex portion, 256, 257, 258, long hole, 259, first projection piece, 260. ..Sheet stacking portion side plates, 261, 262 ... engaging convex portions, 265 ... second projecting pieces, 270 ... shaft, 271 ... first guide side plate, 272 ... second guide side plate 273: first guide long hole, 274: second guide long hole, 300: paper number counting unit, 310: paper number counting unit, 311: movable claw piece for counting , 312 ... fixed claw piece for counting, 315 ... movable claw for counting Fulcrum, 317 ... photo sensor unit, 400 ... feed cassette loading thickness detection sensor, 501 ... control unit, 502 ... engine controller unit, 503 ... near empty detection unit, 505 ... counter

Claims (6)

A fixed claw piece for counting which gives elasticity to the paper edge of the paper which is shifted one by one;
A counting claw repelled by a sheet released from the elasticity imparted by the counting claw;
A counting movable claw piece fulcrum for rotating the counting movable claw piece at its center;
An apparatus for counting the number of sheets in a sheet feeding cassette, comprising: a photosensor unit through which a part of the counting movable claw piece passes in accordance with an operation of being repelled by a sheet. 2. The sheet count device for a sheet feeding cassette according to claim 1, wherein the movable claw piece for counting is provided with a notch from the upper side to the lower side. 3. The sheet number counting device for a sheet feeding cassette according to claim 1, wherein the counting claw piece is provided with a cut portion from a lower side portion to an upper side portion. A part of the counting movable claw piece passing through the photosensor unit is the other side different from the side where the counting movable claw piece is repelled by the paper. 4. The paper sheet counting device for a paper feed cassette according to any one of 3 above. 2. The counting fixed claw piece, the counting movable claw piece, the counting movable claw piece fulcrum, and the photo sensor unit are unitized as a sheet number counting unit. Item 5. The sheet number counting device of the sheet feeding cassette according to any one of Items 4 to 5. 6. The sheet number counting device for a sheet feeding cassette according to claim 1, wherein the sheet number counting unit performs scanning in the direction of shifting the sheet edge of each sheet. .

Images