JP6296342B2 - Sheet material discrimination apparatus and image forming apparatus - Google Patents

Description

  The present invention relates to a sheet material discriminating apparatus that discriminates a sheet material, and an image forming apparatus including the sheet material discriminating apparatus.

  2. Description of the Related Art Conventionally, it is known that an image forming apparatus automatically determines the type of sheet material and sets image forming conditions according to the determined type of sheet material in order to improve the quality of printed matter. In the image forming apparatus described in Patent Document 1, a sheet material discrimination device that discriminates information on a sheet material conveyed in a sheet material conveyance path is provided inside the image forming apparatus.

  This sheet material discriminating apparatus includes a sheet material information detection sensor including an optical sensor having a light emitting element and a light receiving element, which is information detecting means for detecting information on the sheet material. In this sheet material information detection sensor, a light receiving element is provided at a position where light reflected from the surface of the sheet material out of light emitted from the light emitting element toward the sheet material can be received.

  Then, the light emitting element of the sheet material information detection sensor emits light, irradiates the light toward the sheet material conveyed in the sheet material conveyance path, and the reflected light reflected on the surface of the sheet material is received by the light receiving element, Information on the sheet material is detected from optical information such as the amount of reflected light received.

  In this way, based on the sheet material information detected by the optical sensor, the sheet material is determined by the control unit that is a determination unit that determines the sheet material, and image forming conditions are set according to the type of the sheet material. ing.

  However, when light is emitted from the light emitting element of the optical sensor to the deformation portion of the sheet material that has been deformed such as curling or corrugation during conveyance, the reflection of the light on the surface of the sheet material depends on the state of deformation. Since the method is different, the optical information of the light received by the light receiving element is different. Therefore, accurate sheet material information cannot be detected, and the accuracy of sheet material discrimination may be reduced.

  On the other hand, the inventors of the present application have developed a sheet material discriminating apparatus that is used outside the image forming apparatus and not inside the image forming apparatus.

  An opening through which the sheet material can be inserted and removed is provided on the side wall of the exterior case of the sheet material discrimination device. In addition, a sheet material placing portion on which the sheet material inserted from the opening is placed is provided inside the exterior case, and an optical sensor for detecting information on the sheet material is placed on the sheet material. It is provided facing the part.

  Then, when determining the type of sheet material, the operator confirms that the sheet material is not deformed, such as curl, while inserting the sheet material held by the operator into the exterior case from the opening, The sheet material is placed on the sheet material placing portion, and the sheet material information is detected by the optical sensor. Accordingly, it is possible to suppress the detection of information on the deformation portion of the sheet material by the optical sensor, and it is possible to detect the accurate sheet material information and to prevent the accuracy of the determination of the sheet material from being lowered.

  In addition, the sheet material information at a plurality of positions of the sheet material is obtained at a predetermined sampling interval while moving the sheet material within the opening so as to pass through the information detectable position where the information of the sheet material can be detected by the optical sensor. Detection is performed by an optical sensor, and detection results are averaged. As a result, as the number of samples of the sheet material information detected by the optical sensor increases, it is possible to determine the sheet material with higher accuracy while suppressing measurement errors and the like.

  However, since the operator holds the sheet material in his hand and inserts or pulls out the sheet material from the opening, the faster the operation, the shorter the time for detecting the sheet material information by the optical sensor. Therefore, the number of detected sheet material information samples is reduced.

  Therefore, even if the sheet material is determined based on the detected sheet material information, the determination accuracy is low, and the image forming conditions set based on the determination result correspond to the type of the sheet material. May not be appropriate.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a sheet material discriminating apparatus capable of suppressing a reduction in sheet material discrimination accuracy, and an image forming apparatus including the sheet material discriminating apparatus. Is to provide.

  In order to achieve the above object, the invention of claim 1 includes information detecting means for detecting information on a sheet material, and discriminating means for discriminating a sheet material based on information on the sheet material detected by the information detecting means. The sheet material is moved relative to the apparatus in a state where at least a part of the sheet material is located at an information detectable position, which is a position where information of the sheet material can be detected by the information detection means in the apparatus, A sheet material discriminating device for detecting sheet material information at a plurality of locations on a sheet material by an information detecting unit and used outside the image forming apparatus. Detectable time detection means for detecting the detectable time when the sheet material information could be detected, and the detectable time detected by the detectable time detection means, If shorter than the first reference time is because setting, is characterized in that a control means for controlling said discrimination means so as not to determine the sheet material.

  As mentioned above, according to this invention, there exists an outstanding effect that it can suppress that the discrimination | determination precision of a sheet | seat material becomes low.

6 is a flowchart illustrating an example of sheet material determination control by the sheet material determination device according to Configuration Example 1; 1 is a schematic configuration diagram of an image forming system according to an embodiment. FIG. 3 illustrates an image forming apparatus. The figure explaining a sheet material post-processing apparatus. 1 is a schematic configuration diagram of a sheet material discrimination device according to Configuration Example 1. FIG. The figure for demonstrating an optical sensor and a processing apparatus. The figure for demonstrating a surface emitting laser array. The figure for demonstrating the incident angle of the irradiation light to a sheet | seat material. The figure for demonstrating the arrangement position of the light receivers 113 and 114. FIG. (A) The figure for demonstrating surface regular reflection light, (b) The figure for demonstrating surface diffuse reflection light, (c) The figure for demonstrating internal reflection light. The figure for demonstrating the light received with the light receivers 113 and 114. FIG. The figure for demonstrating the light which injects into the polarizing filter. The figure for demonstrating the arrangement position of the light receivers 115 and 118. FIG. The figure which shows the state which the front-end | tip of the sheet | seat material contact | abutted to the stopper. The figure which shows the state which the front-end | tip of the sheet | seat material left | separated from the stopper. The figure which shows the state which the sheet material slipped out from the position which can detect sheet material information by a sheet material information detection sensor. The graph which showed the change of sheet material information detection sensor output value. Explanatory drawing about the case where the sheet material information detectable time t is shorter than the preset reference time t1. Explanatory drawing about the case where the sheet | seat material information detectable time t is longer than the preset reference time t2. (A) A schematic diagram showing a state where the error display lamp is not lit, (b) a schematic diagram showing a state where the error display lamp is lit. FIG. 6 is a schematic configuration diagram of a sheet material determination device according to Configuration Example 2; Operation | movement explanatory drawing of a sheet material holding | grip mechanism. 10 is a flowchart showing an example of sheet material discrimination control by the sheet material discrimination device according to Configuration Example 2. The figure which shows the state which hold | gripped the sheet material with the sheet material holding member and the upper sensor unit holding member. Explanatory drawing in the case of raising the holding | grip force of a sheet material by a sheet material holding member and an upper sensor unit holding member. Explanatory drawing in the case of weakening the holding force of the sheet material by a sheet material holding member and an upper sensor unit holding member. FIG. 10 is a schematic configuration diagram of a sheet material determination device according to Configuration Example 3; The schematic block diagram of the sheet material thickness detection sensor installed in the sheet material discrimination | determination apparatus.

  FIG. 2 is a schematic configuration diagram of the image forming system according to the present embodiment. As illustrated in FIG. 2, the image forming system 1 includes an image forming apparatus 2 and a sheet material post-processing apparatus 3 as a sheet material processing apparatus. The image forming apparatus 2 and the sheet material post-processing apparatus 3 are connected to be able to communicate with each other. In the image forming system 1, after the image forming apparatus 2 forms an image on the sheet material P, the sheet material post-processing apparatus 3 receives the sheet material P from the image forming apparatus 2 and performs various post-processing on the received sheet material P. Apply.

  The various post-processing includes, for example, end binding processing, center folding processing, and the like. The half-folding process includes a saddle stitching process. The sheet material post-processing apparatus 3 that performs such various post-processing has a discharge mode, an end binding mode, and a middle folding mode as operation modes.

FIG. 3 is a diagram illustrating the image forming apparatus 2.
In the image forming apparatus main body 400, a feeding cassette that stores a sheet material that is a recording medium is disposed below the image forming unit. The sheet materials stored in the feeding cassette are fed by feeding rollers 414 a and 414 b, and then are conveyed upward along a predetermined conveyance path to reach the registration roller pair 413.

  The image forming unit includes a photosensitive drum 401 as an image carrier, a charging device 402, an exposure device 410, a developing device 404, a transfer device 405, and a cleaning device 406.

  The charging device 402 is a charging unit that uniformly charges the surface of the photosensitive drum 401. The exposure device 410 is a latent image forming unit that forms an electrostatic latent image on the photosensitive drum 401 based on image information read by the image reading device 300. The developing device 404 is a developing unit that visualizes an electrostatic latent image on the photosensitive drum 401 by attaching toner.

  The transfer device 405 is a transfer unit that transfers the toner image on the photosensitive drum 401 to a sheet material. The cleaning device 406 is a cleaning unit that removes toner remaining on the photosensitive drum 401 after transfer. A fixing device 407 as a fixing unit that fixes the toner image to the sheet material is disposed on the downstream side in the sheet material conveyance direction of the image forming unit.

  The exposure apparatus 410 emits laser light based on image information under the control of a control unit (not shown) and the laser light from the laser unit 411 in the rotation axis direction (main scanning direction) of the photosensitive drum 401. A polygon mirror 412 for scanning is provided.

  An automatic document feeder 500 is connected to the upper part of the image reading apparatus 300. The automatic document feeder 500 includes a document table 501, a document separating and feeding roller 502, a conveyor belt 503, and a document discharge tray 504.

  When an original is set on the original table 501 and an instruction to start reading is received, the automatic original conveying apparatus 500 sends out the originals on the original table 501 one by one by the original separation feeding roller 502. Then, the document is guided onto the platen glass 309 by the conveyance belt 503 and temporarily stopped.

  Then, the image information of the original temporarily stopped on the platen glass 309 is read by the image reading device 300. Thereafter, the conveyance belt 503 resumes the conveyance of the document, and the document is discharged to the document discharge tray 504.

Next, an image reading operation and an image forming operation will be described.
When a document is transported on the platen glass 309 by the automatic document transport device 500 or a document is placed on the platen glass 309 by an operator and a copy start operation is performed on the operation panel 4, the first traveling body 303. The upper light source 301 is turned on. At the same time, the first traveling body 303 and the second traveling body 306 are moved along a guide rail (not shown).

  The original on the platen glass 309 is irradiated with light from the light source 301, and the reflected light is guided to the mirror 302 on the first traveling body 303, the mirrors 304 and 305 on the second traveling body 306, and the lens 307. The light is received by the CCD 308. As a result, the CCD 308 reads the image information of the document, and the image information is converted from analog data to digital data by an A / D conversion circuit (not shown). The image information is sent from an information output unit (not shown) to the control unit of the image forming apparatus main body 400.

  On the other hand, the image forming apparatus main body 400 starts to drive the photosensitive drum 401, and when the photosensitive drum 401 rotates at a predetermined speed, the charging device 402 uniformly charges the surface of the photosensitive drum 401. Then, an electrostatic latent image based on image information read by the image reading device is formed by the exposure device 410 on the surface of the charged photosensitive drum 401.

  Thereafter, the electrostatic latent image on the surface of the photosensitive drum 401 is developed by the developing device 404 to become a toner image. Further, the sheet material stored in the feeding cassette is fed by feeding rollers 414 a and 414 b and is temporarily stopped by a pair of registration rollers 413.

  The toner image formed on the surface of the photosensitive drum 401 is sent to the transfer unit by the registration roller pair 413 at the timing when the leading end of the toner image reaches the transfer unit facing the transfer device 405. When the sheet material passes through the transfer portion, the toner image formed on the surface of the photosensitive drum 401 by the action of the transfer electric field is transferred onto the sheet material.

  Thereafter, the sheet material on which the toner image is placed is conveyed to the fixing device 407, subjected to fixing processing by the fixing device 407, and then discharged to the subsequent sheet material post-processing device 3. The transfer residual toner remaining on the surface of the photosensitive drum 401 without being transferred to the sheet material in the transfer portion is removed by the cleaning device 406.

  FIG. 4 is a diagram illustrating the sheet material post-processing device 3. The sheet material post-processing device 3 is provided with a first transport path Pt1 for receiving the sheet material P discharged from the image forming device 2 and discharging the sheet material P to the first paper discharge tray 10. Also, a second conveyance path Pt2 for branching from the first conveyance path Pt1 to perform edge binding processing or the like on the sheet bundle, and connected to the second conveyance path Pt2 to perform saddle stitching and middle folding processing on the sheet bundle. A third transport path Pt3 is provided.

  The first transport path Pt1, the second transport path Pt2, and the third transport path Pt3 are formed by, for example, guide members (not shown). In the first conveyance path Pt1, an entrance roller 11, a conveyance roller 12, a conveyance roller 13, and a paper discharge roller 14 are sequentially arranged from the upstream side in the sheet conveyance direction to the downstream side of the first conveyance path Pt1.

  The entrance roller 11, the transport roller 12, the transport roller 13, and the paper discharge roller 14 are rotationally driven by a motor as a drive source to transport the sheet material P. An inlet sensor 15 is disposed upstream of the inlet roller 11 in the sheet material conveyance direction. The inlet sensor 15 detects that the sheet material P has been carried into the sheet material post-processing apparatus 3.

  A branching claw 17 is disposed on the downstream side of the conveying roller 12 in the sheet material conveying direction. The branching claw 17 rotates and switches its position, so that the branching claw 17 moves to the downstream side of the branching claw 17 in the sheet material conveyance direction of the first conveyance path Pt1 and the second conveyance path Pt2. The material P is selectively guided. The branch claw 17 is driven by, for example, a motor or a solenoid.

  In the discharge mode, the sheet material P carried into the first transport path Pt1 from the image forming apparatus 2 is transported by the entrance roller 11, the transport roller 12, the transport roller 13, and the paper discharge roller 14, and the first paper discharge tray 10 is discharged. To be discharged. On the other hand, in the end binding mode and the middle folding mode, the sheet material P carried into the first conveyance path Pt1 is conveyed by the entrance roller 11 and the conveyance roller 12, and the traveling direction is changed by the branch claw 17, and the second conveyance is performed. It is conveyed to the route Pt2.

  In the second transport path Pt2, the transport roller 20, the transport roller 21, the transport roller 22, the sheet material stacking tray 23, the first sheet material aligning unit 24, and the end binding processing unit (first binding processing unit) 25 are provided. And are arranged. The conveyance roller 20, the conveyance roller 21, and the conveyance roller 22 are driven by a motor to convey the sheet material P. The first sheet material aligning unit 24 is driven by a motor.

  Further, a branching claw 26 and a branching claw 27 are arranged on the downstream side of the sheet material stacking tray 23 in the sheet material conveyance direction. The branching claw 26 and the branching claw 27 are rotated to switch their positions, so that the sheet material P is separated from the downstream portion of the branching claw 17 in the sheet material conveyance direction in the first conveyance path Pt1 and the third conveyance path. The sheet material P is selectively guided to one of Pt3. The branch claw 26 and the branch claw 27 are driven by, for example, a motor or a solenoid.

  In the edge binding mode, the sheets are sequentially stacked on the sheet material stacking tray 23. Thereby, a sheet bundle in which a plurality of sheet materials P are laminated is formed. At this time, the sheet material P comes into contact with a first movable reference fence (not shown) provided on the sheet material stacking tray 23 at the rear end thereof, and the sheet material conveyance direction position is aligned, and the first sheet material aligning unit 24 The position in the width direction is aligned.

  Here, the sheet material stacking tray 23, the first sheet material aligning unit 24, and the first movable reference fence constitute a first bundling unit 28 as a bundling unit that stacks a plurality of sheet materials P into a sheet bundle. ing. The first bundling unit 28 also includes a motor that drives the first sheet material aligning unit 24 and a motor that drives the first movable reference fence.

  The sheet bundle with the ends bound is transported to the first transport path Pt1 by the first movable reference fence, and then transported by the transport roller 13 and the paper discharge roller 14 to be discharged to the first paper discharge tray 10.

  Here, the paper discharge roller 14 is an example of a paper discharge unit that discharges the sheet bundle bound by the edge binding processing unit 25. On the other hand, in the middle folding mode, the sheet material P conveyed to the second conveyance path Pt2 is conveyed to the third conveyance path Pt3 by the conveyance rollers 20, the conveyance rollers 21, the conveyance rollers 22, and the first movable reference fence.

  In the third conveyance path Pt3, a conveyance roller 31, a conveyance roller 32, and a saddle stitch folding portion 33 are arranged. The conveyance roller 31 and the conveyance roller 32 are driven by a motor to convey the sheet material P. The saddle stitch folding unit 33 includes a center folding unit 34, a saddle stitching processing unit (second binding processing unit) 35, and a second bundling unit 36.

  The sheet material P conveyed to the third conveyance path Pt3 is sequentially stacked on the second bundle unit 36 by the conveyance roller 31 and the conveyance roller 32. Thereby, a sheet bundle in which a plurality of sheet materials P are laminated is formed. That is, the second bundling unit 36 includes a plurality of sheet materials conveyed by the conveyance unit 51 including the entrance roller 11, the conveyance roller 12, the conveyance roller 20, the conveyance roller 21, the conveyance roller 22, the conveyance roller 31, and the conveyance roller 32. P is overlapped to form a sheet bundle.

  At this time, the front end of the sheet material P comes into contact with the second movable reference fence 37, the position in the sheet material conveyance direction is aligned, and the position in the width direction is aligned by a second sheet material alignment unit (not shown). The sheet bundle is saddle-stitched by the saddle stitching processing unit 35 in the vicinity of the center in the sheet material conveyance direction. The saddle stitched sheet bundle is returned to the center folding position by the second movable reference fence 37. The second movable reference fence 37 is driven by a motor.

  The sheet bundle positioned at the middle folding position is folded in the middle in the sheet material conveyance direction by the middle folding section 34. In the middle folding portion 34, the folding blade 38 facing the central portion in the sheet material conveyance direction of the sheet bundle at the middle folding position moves from right to left in FIG. 2 to bend the central portion in the sheet material conveyance direction of the sheet bundle. However, it is pushed between the lower pressing roller 39 and the upper pressing roller 40. The folding blade 38 is driven by a motor.

  The folded sheet bundle is pressed from above and below by the lower pressing roller 39 and the upper pressing roller 40. The lower pressing roller 39 and the upper pressing roller 40 are driven by a motor. The sheet bundle folded in this way is discharged onto the second discharge tray 42 by the lower pressing roller 39, the upper pressing roller 40, and the discharge roller 41.

[Configuration example 1]
FIG. 5 is a schematic configuration diagram of the sheet material discrimination device 100 according to Configuration Example 1. The sheet material discriminating apparatus 100 includes a sheet material information detection sensor 110, and the sheet material information detection sensor 110 is used to discriminate the type of the sheet material P.

  The sheet material discriminating apparatus 100 is connected to the image forming apparatus 2 via a communication cable 60 (see FIG. 2), and communication is possible between the sheet material discriminating apparatus 100 and the image forming apparatus 2. The sheet material information detection sensor 110 includes an upper sensor unit 110A provided with a light source and a light receiver that receives reflected light, an upper sensor unit 110A provided with a light receiver that receives transmitted light, and the like. Have.

  The sheet material information detection sensor 110 and the processing device 130 will be described with reference to FIG. As shown in FIG. 6 as an example, the sheet material information detection sensor 110 houses a light source 111, a collimating lens 112, light receivers 113, 114, 115, 118, 160, polarizing filters 116, 117, and these. It has dark boxes 119A, 119B and the like.

  The dark boxes 119A and 119B are metal box members, for example, aluminum box members, and black alumite treatment is applied to the surface in order to reduce the influence of disturbance light and stray light.

  The light source 111 has a plurality of light emitting units. Each light emitting unit is a vertical cavity surface emitting laser (VCSEL). That is, the light source 111 includes a surface emitting laser array (VCSEL array). Here, as shown in FIG. 7 as an example, nine light emitting units are two-dimensionally arranged.

  The light source 111 is arranged so that the sheet material P is irradiated with S-polarized linearly polarized light. Further, the incident angle θ (see FIG. 8) of the light from the light source 111 to the sheet material P is 80 [°]. The light source 111 is turned on and off by the processing device 130.

  The collimating lens 112 is disposed on the optical path of the light emitted from the light source 111 and makes the light substantially parallel light. The light passing through the collimating lens 112 passes through an opening provided in the dark box 119A and illuminates the sheet material P. In the following, the center of the illumination area on the surface of the sheet material P is abbreviated as “illumination center”. The light that has passed through the collimator lens 112 is also referred to as “irradiation light”.

  By the way, when light is incident on the boundary surface of the medium, a surface including the incident light ray and the normal of the boundary surface set at the incident point is called an “incident surface”. Therefore, when the incident light is composed of a plurality of light beams, there is an incident surface for each light beam. Here, for convenience, the incident surface of the light beam incident on the illumination center is referred to as the incident surface of the sheet material P. And That is, the plane that includes the illumination center and is parallel to the XZ plane is the incident plane of the sheet material P.

  In this embodiment, the expressions S-polarized light and P-polarized light are used for reflected light as well as incident light on the sheet material P. However, for the sake of easy understanding, this is incident on the sheet material P. This is an expression based on the polarization direction of light. In the incident plane, the same polarization direction as that of incident light (here, S-polarized light) is referred to as S-polarized light, and the polarization direction orthogonal thereto is referred to as P-polarized light.

  The polarizing filter 116 is disposed on the + Z side of the illumination center. The polarizing filter 116 is a polarizing filter that transmits P-polarized light and shields S-polarized light. Note that a polarizing beam splitter having an equivalent function may be used instead of the polarizing filter 116.

  The light receiver 114 is disposed on the + Z side of the polarizing filter 116 and receives light transmitted through the polarizing filter 116. Here, as shown in FIG. 9, the angle ψ1 formed by the line L1 connecting the illumination center, the center of the polarizing filter 116, and the center of the light receiver 114 and the surface of the sheet material P is 90 °.

  The light receiver 113 is disposed on the + X side of the illumination center with respect to the X-axis direction. As shown in FIG. 9, the angle ψ2 formed by the line L2 connecting the illumination center and the center of the light receiver 113 and the surface of the sheet material P is 170 [°]. The center of the light source 111, the center of illumination, the center of the polarizing filter 116, and the center of each light receiver are present on substantially the same plane.

  By the way, the reflected light from the sheet material P when the sheet material P is illuminated can be divided into reflected light reflected by the surface of the sheet material P and reflected light reflected inside the sheet material P. . Moreover, the reflected light reflected on the surface of the sheet material P can be divided into specularly reflected light and diffusely reflected light.

  Hereinafter, for convenience, the reflected light regularly reflected on the surface of the sheet material P is also referred to as “surface regular reflected light”, and the reflected light that is diffusely reflected is also referred to as “surface diffuse reflected light” (FIG. 10A and FIG. b)).

  The surface of the sheet material P is composed of a flat portion and a slope portion, and the smoothness of the sheet material surface is determined by the ratio. The light reflected by the plane portion becomes surface regular reflection light, and the light reflected by the slope portion becomes surface diffuse reflection light. The surface diffuse reflection light is reflected light that is completely scattered and reflected, and the reflection direction can be considered to be isotropic. And the light quantity of surface regular reflection light increases, so that smoothness becomes high.

  On the other hand, when the sheet material P is a general printing paper, the reflected light from the inside of the sheet material P is only diffusely reflected light because it is scattered multiple times in the fibers inside. Hereinafter, for the sake of convenience, the reflected light from the inside of the sheet material P is also referred to as “internally reflected light” (see FIG. 10C). Similar to the surface diffuse reflection light, the internal reflection light is also a reflection light that is completely scattered and reflected, and the reflection direction can be considered to be isotropic.

  The polarization direction of the surface regular reflection light and the surface diffuse reflection light toward the light receiver is the same as the polarization direction of the incident light. By the way, in order for the polarization direction to rotate on the surface of the sheet material P, incident light must be reflected by a surface inclined in the direction of rotation with respect to the incident direction. Here, since the center of the light source, the center of illumination, and the center of each light receiver are on the same plane, the reflected light whose polarization direction is rotated on the surface of the sheet material P is not reflected in any light receiver direction.

  On the other hand, the polarization direction of the internally reflected light is rotated with respect to the polarization direction of the incident light. This is presumably because the light that has entered the inside of the sheet material P passes through the fiber, rotates while being scattered multiple times, and the polarization direction rotates.

  Reflected light in which surface diffuse reflected light and internal reflected light are mixed enters the polarizing filter 116 (see FIG. 11). Since the surface diffuse reflection light is the same S-polarized light as the incident light, it is shielded by the polarization filter 116. On the other hand, since the internally reflected light includes S-polarized light and P-polarized light, the P-polarized light component is transmitted through the polarizing filter 116. That is, the P-polarized component included in the internally reflected light is received by the light receiver 114 (see FIG. 12).

  Hereinafter, for convenience, the P-polarized component included in the internally reflected light is also referred to as “P-polarized internally reflected light”. Further, the S-polarized component contained in the internally reflected light is also referred to as “S-polarized internally reflected light”.

  The inventors have confirmed that the amount of P-polarized internally reflected light has a correlation with the thickness and density of the sheet material P. This is because the light amount of the P-polarized internally reflected light depends on the path length when passing through the fibers of the sheet material P.

  Reflected light that is a mixture of surface regular reflection light, surface diffuse reflection light, and internal reflection light is incident on the light receiver 113. At this light receiving position, the light amount of the surface diffuse reflection light and the internal reflection light is very small compared to the light amount of the surface regular reflection light. Therefore, the light reception amount of the light receiver 113 can be regarded as the light amount of the surface regular reflection light. Yes (see FIG. 11).

  The light receiver 115 is disposed at a position for receiving the surface diffuse reflection light and the internal reflection light. For example, the angle ψ3 formed by the line L3 connecting the illumination center shown in FIG. 13 and the center of the light receiver 115 and the surface of the sheet material P is 120 [°]. The center of the light source 111, the center of illumination, the center of the polarizing filter 116, and the center of each light receiver are present on substantially the same plane.

  The polarizing filter 117 is disposed on the optical path of the surface diffuse reflection light and the internal reflection light. The polarizing filter 117 is a polarizing filter that transmits P-polarized light and shields S-polarized light. The light receiver 118 is disposed on the optical path of the light transmitted through the polarizing filter 117. Therefore, the light receiver 118 receives the P-polarized component included in the internally reflected light.

  For example, an angle ψ4 formed by a line L4 connecting the illumination center, the center of the polarizing filter 117, and the center of the light receiver 118 shown in FIG. 13 and the surface of the sheet material P is 150 [°]. The center of the light source 111, the center of illumination, the center of the polarizing filter 116, the center of the polarizing filter 117, and the center of each light receiver are present on substantially the same plane.

  The light receiver 160 is disposed at a position for receiving transmitted light that passes through the sheet material P among the light irradiated on the sheet material P from the light source 111. Each light receiver outputs an electrical signal (current signal) corresponding to the amount of received light to the processing device 130.

  Returning to FIG. 6, the processing device 130 includes a light source driving circuit 131, a current-voltage conversion circuit 132, an AD conversion circuit 133, and the like, and is fixed to the dark box 119A. The light source drive circuit 131 outputs a light source drive signal to the light source 111 in accordance with an instruction from the control unit 600. The current-voltage conversion circuit 132 converts the current signal from each light receiver into a voltage signal. The AD conversion circuit 133 converts the analog signal that has passed through the current-voltage conversion circuit 132 into a digital signal, and outputs the digital signal to the control unit 600.

  As in the present embodiment, in addition to the information from the light receivers 113, 114, 115, 118 that receive the reflected light, the information from the light receiver 160 that receives the transmitted light is also included, so that the sheet material P with higher accuracy can be obtained. Can be determined.

  Further, at least a regular reflection light receiver that receives light regularly reflected on the sheet material P among light irradiated from the light source, and a diffuse reflection light receiver that receives light diffusely reflected on the sheet material P. It is preferable to use the sheet material information detection sensor 110 that includes it. Thereby, since it can detect with the sensor which installed the diffused molecule of the reflected light with respect to the sheet | seat material P in several different angles, a detection result with a higher precision than the information of only regular reflection can be obtained.

  The upper sensor unit 110A and the lower sensor unit 110B are held by the upper sensor unit holding member 103 and the lower sensor unit holding member 104, respectively. The upper sensor unit holding member 103 and the lower sensor unit holding member 104 are urged away from each other by the urging force from the elastic body 105. Therefore, as shown in FIG. 5, the sheet material P can be inserted between the upper sensor unit 110A and the lower sensor unit 110B and between the upper sensor unit holding member 103 and the lower sensor unit holding member 104. A gap is formed.

  The gap is desirably sized so that the gap is pushed and expanded by the sheet material P when the sheet material P is inserted. At this time, at least by the upper sensor unit 110A and the lower sensor unit 110B. The sheet material P is held.

  The elastic body 106 connects the lower sensor unit holding member 104 and the lower sensor unit 110B, and the lower sensor unit 110B can swing up and down with respect to the lower sensor unit holding member 104 by the elastic body 106. Yes. Then, by swinging the lower sensor unit 110B in the vertical direction with respect to the lower sensor unit holding member 104, the sheet material P can be gripped with a constant force.

  The upper sensor unit holding member 103 is provided with a stopper 8 that regulates the leading end position of the sheet material P inserted into the sheet material determination apparatus 100. Further, a sheet material position detection sensor 9 for detecting the position of the sheet material P is provided on the upper sensor unit 110 </ b> A side in the sheet material conveyance direction from the stopper 8.

  In this configuration example, the operator confirms that the sheet material P is not curled or the like, and inserts the sheet material P held by the operator into the gap. When the sheet material P enters until the leading end of the sheet material abuts against the stopper 8, the sheet material position detection sensor 9 reacts to detect that the sheet material P is in a restricted position by the stopper 8.

  Next, sheet material discrimination control by the sheet material discrimination device 100 will be described. FIG. 1 is a flowchart illustrating an example of sheet material discrimination control by the sheet material discrimination device 100 according to the configuration example 1.

  In the sheet material discriminating apparatus 100, the sheet material P is inserted between the upper sensor unit 110A and the lower sensor unit 110B and between the upper sensor unit holding member 103 and the lower sensor unit holding member 104 as described above. Possible gaps are formed. When discriminating the sheet material P, first, the operator confirms that the sheet material P is not curled or deformed, and the sheet material P held by the operator is placed in the gap. Insert (S1).

  When the sheet material P is inserted into the sheet material discriminating apparatus 100 at a certain level or more, as shown in FIG. 14, the leading edge of the sheet material P hits the stopper 8, and the sheet material P can be further inserted. Disappear. Further, the sheet material P is detected by the sheet material position detection sensor 9 at the timing when the leading edge of the sheet material P hits the stopper 8 in this way (YES in S2).

  When the sheet material P is detected by the sheet material position detection sensor 9, the control unit 600 determines that the sheet material P is located at a normal detection start position for detecting the sheet material information by the sheet material information detection sensor 110. The Thereafter, drawing of the sheet material P is started from the sheet material discrimination device 100 (S4), and when the leading edge of the sheet material P is separated from the stopper 8 as shown in FIG. It will not be detected.

  When the sheet material P is no longer detected by the sheet material position detection sensor 9 (YES in S5), the control unit 600 determines that the sheet material P is moving, and the sheet material information detected by the sheet material information detection sensor 110 is detected. Is started (S6). Then, while the sheet material P is pulled out from the sheet material determination apparatus 100, the sheet material information detection sensor 110 detects the sheet material information a plurality of times (S7).

  Thus, by repeating the detection operation of the sheet material information a plurality of times for a certain period of time by the sheet material information detection sensor 110, it becomes possible to obtain the sheet material information at a plurality of locations of the sheet material P. The discrimination accuracy of the sheet material P can be improved.

  When the sheet material P continues to be pulled out and the sheet material P passes through the position X where the sheet material information detection sensor 110 can detect the sheet material information as shown in FIG. 16, the output of the sheet material information detection sensor 110 as shown in FIG. The value (information detected) suddenly changes greatly. When such a change in the output value of the sheet material information detection sensor 110 occurs (YES in S8), the control unit 600 determines that the sheet material P has passed the sheet material information detectable position X at that timing. (S9).

  In addition, the passage time from the start of detection of sheet material information to the end of passage through the position where sheet material information can be detected is measured by a timer that is a measuring unit provided in the control unit 600. Then, the measured passing time is a sheet material information detectable time t in which the sheet material information detection sensor 110 can detect the sheet material information on the sheet material P that moves relative to the sheet material determination apparatus 100. It is detected by the control unit 600 (S10).

  In the sheet material determination apparatus 100 of the configuration example 1, the control unit 600 determines whether or not the sheet material information detection sensor 110 has normally detected the sheet material information based on the sheet material information detectable time t. To do.

  That is, when the sheet material information detectable time t is shorter than the preset reference time t1, the sheet material information detection sensor 110 cannot detect the sheet material information a predetermined number of times set in advance (FIG. 18). See), and the discrimination accuracy of the sheet material P is lowered. Therefore, when the sheet material information detectable time t is shorter than the preset reference time t1, the operator is notified that the sheet material information has not been normally detected, and the sheet material information is re-established. It encourages detection.

  On the other hand, when the sheet material P is stopped in the sheet material determination apparatus 100 at the time of detecting the sheet material information, or when the sheet material P is hardly moved, the sheet material information of the same portion of the sheet material P is displayed as shown in FIG. There is a possibility that the sheet material information detection sensor 110 detects a plurality of times. When the sheet material P is discriminated using the sheet material information detected from the same part of the sheet material P in this way, there is a possibility that the discrimination accuracy of the sheet material P is lowered, and the normal sheet material The discrimination of P cannot be guaranteed.

  For this reason, in the configuration example 1, even when the sheet material information detectable time t (the passage time) is longer than the preset reference time t2, it is determined that the sheet material information is not normally detected. To re-detect the sheet material information. The reference time t1 and the reference time t2 satisfy the relationship t1 <t2.

  Examples of a method for notifying that the detection of the sheet material information has not been normally performed include the following. That is, in the sheet material discrimination device 100 of the configuration example 1, as shown in FIG. 20A, the operator is notified that the sheet material information has not been normally detected on the upper surface of the upper sensor unit holding member 103. An error display lamp 120 imitating an exclamation mark “!” For notification is provided.

  The error display lamp 120 is not lit when the sheet material information is not detected or when the sheet material information is normally detected (see FIG. 20A), and the sheet material information is detected. If the operation is not performed normally, it is lit in red (see FIG. 20B).

  If the sheet material information detectable time t is shorter than the reference time t1 or longer than the reference time t2 (YES in S11), it is determined that the sheet material information is not normally detected and an error is displayed. The lamp 120 is lit red (S13). As a result, the operator visually recognizes that the error display lamp 120 is lit in red, thereby easily grasping that the detection of the sheet material information has not been performed normally and prompting the re-detection of the sheet material information. be able to.

  On the other hand, when the sheet material information detectable time t is longer than the reference time t1 and shorter than the reference time t2 (NO in S11), it is determined that the sheet material information has been normally detected and the detected sheet material is detected. Based on the information of P, the control unit 600 determines the sheet material P (S12).

  Thus, an appropriate sheet material in which the sheet material information is detected a plurality of times from the same portion of the sheet material P while the sheet material information detection sensor 110 performs a predetermined number of times of preset sheet material information detection. Based on the information, it is possible to determine the sheet material P with high accuracy.

  Then, based on the determination result of the sheet material P, the brand material candidates of the sheet material P are displayed on the display unit of the operation panel 4 provided in the image forming apparatus 2, and according to the type of the sheet material P listed as the brand material candidate. The image forming conditions are set and image formation is performed.

[Configuration example 2]
FIG. 21 is a schematic configuration diagram of a sheet material determination device 100 according to Configuration Example 2. The sheet material discriminating apparatus 100 is provided with a sheet material gripping mechanism 150 for gripping the sheet material P. The sheet material gripping mechanism 150 includes a sheet material gripping member 151, two cams 152 and 153, a drive transmission device 154, a drive generation device 155, and the like.

  FIG. 22 is an explanatory diagram of the operation of the sheet material gripping mechanism 150. The cams 152 and 153 are constrained in only one direction and can be rotated. The sheet material gripping member 151 and the cams 152 and 153 are in physical contact with each other, and the sheet material gripping member 151 moves up and down as the cams 152 and 153 rotate.

  The cams 152 and 153 receive drive transmission from the drive generation device 155 through the drive transmission device 154, and the rotational position is controlled to a target position. As a result, the sheet material gripping member 151 is also controlled to the target position, so that the force received by the sheet material P can also be controlled.

  The sheet material discriminating apparatus 100 of the present configuration example includes a sheet material gripping member 151 instead of the elastic body 106 provided in the sheet material discriminating apparatus 100 of the configuration example 1. The sheet material discriminating apparatus 100 should remove noises unnecessary for paper type detection such as fluttering of the sheet material P by putting different sheet thicknesses in the same apparatus and holding the sheet material P during the detection operation. I must.

  Therefore, when the sheet material P is inserted into the sheet material determination apparatus 100, the gap between the upper sensor unit holding member 103 and the lower sensor unit holding member 104 is widened. At the start of detection of sheet material information by the sheet material information detection sensor 110, the sheet material gripping member 151 is configured to restrain the movement of the sheet material P.

  The sheet material discrimination control by the sheet material discrimination device 100 will be described. FIG. 23 is a flowchart illustrating an example of sheet material discrimination control by the sheet material discrimination device 100 according to Configuration Example 2.

  In the sheet material discriminating apparatus 100, the sheet material P is inserted between the upper sensor unit 110A and the lower sensor unit 110B and between the upper sensor unit holding member 103 and the lower sensor unit holding member 104 as described above. Possible gaps are formed. Further, the sheet material determination device 100 in the standby state is located at a position where the sheet material gripping member 151 is lowered from the surface of the lower sensor unit holding member 104.

  Therefore, there is a sufficient space between the sheet material gripping member 151 and the upper sensor unit holding member 103 to insert the sheet material P. When discriminating the sheet material P, first, the operator confirms that the sheet material P is not curled or deformed, and the sheet material P held by the operator is placed in the gap. Insert (S1).

  When the sheet material P is inserted into the sheet material discriminating apparatus 100 at a certain level or more, the leading end of the sheet material P hits the stopper 8 as shown in FIG. 21, and the sheet material P cannot be inserted any more. . Further, the sheet material P is detected by the sheet material position detection sensor 9 at the timing when the leading edge of the sheet material P hits the stopper 8 in this way (YES in S2).

  When the sheet material P is detected by the sheet material position detection sensor 9, it is controlled that the sheet material P is in a set state in which the sheet material information is detected at the normal position of the detection start for detecting the sheet material information by the sheet material information detection sensor 110. The determination is made by the unit 600 (S3).

  After the sheet material P is in the set state, the driving force is transmitted from the drive generator 155 to the cams 152 and 153 through the drive transmission device 154 and rotated, so that the sheet material gripping member 151 is directed toward the upper sensor unit holding member 103. Raise. Then, the sheet material P is held by the sheet material holding member 151 and the upper sensor unit holding member 103 by raising the sheet material holding member 151 to a preset lift position (S4).

  As a result, the sheet material P is restrained so as not to flutter, and the sheet material information detection operation by the sheet material information detection sensor 110 can be stabilized (FIG. 24). After the sheet material P is gripped in this way, the sheet material P starts to be pulled out from the sheet material determination apparatus 100 (S5), and when the leading end of the sheet material P moves away from the stopper 8, the sheet material position detection sensor 9 The sheet material P is not detected.

  When the sheet material P is no longer detected by the sheet material position detection sensor 9 (YES in S6), the control unit 600 determines that the sheet material P is moving, and the sheet material information detected by the sheet material information detection sensor 110 is detected. Is started (S7). Then, while the sheet material P is pulled out from the sheet material determination apparatus 100, the sheet material information detection sensor 110 detects the sheet material information a plurality of times (S8).

  Thus, by repeating the detection operation of the sheet material information a plurality of times for a certain period of time by the sheet material information detection sensor 110, it becomes possible to obtain the sheet material information at a plurality of locations of the sheet material P. The discrimination accuracy of the sheet material P can be improved.

  When the sheet material P continues to be pulled out and the sheet material P passes through the position X where the sheet material information detection sensor 110 can detect the sheet material information, the sheet material information detected by the sheet material information detection sensor 110 suddenly changes greatly. If such a change in sheet material information occurs (YES in S9), the control unit 600 determines that the sheet material P has passed the sheet material information detectable position X at that timing (S10).

  Further, the passage time from the start of detection of the sheet material information to the end of passage through the position where the sheet material information can be detected is measured by a timer which is a measuring unit provided in the control unit 600, and the measured passage time is measured. The detection time t is obtained (S11). In the sheet material determination apparatus 100 of the configuration example 2, the control unit 600 determines whether or not the sheet material information detection sensor 110 has normally detected the sheet material information based on the sheet material information detectable time t. To do.

  When the sheet material information detectable time t (the passage time) is shorter than the reference time t1 or longer than the reference time t2 (YES in S12), the sheet material information is normally detected. If there is no error, the error display lamp 120 is lit red (S14). As a result, the operator visually recognizes that the error display lamp 120 is lit in red, thereby easily grasping that the detection of the sheet material information has not been performed normally and prompting the re-detection of the sheet material information. be able to.

  Here, in the sheet material discriminating apparatus 100 of this configuration example, the rotation operation of the cams 152 and 153 can be freely controlled by the control unit 600. In this configuration example, when the sheet material information is not normally detected, the sheet material information is re-recovered based on the sheet material information detected by the sheet material information detection sensor 110 and the sheet material information detectable time t. The position of the sheet material gripping member 151 at the time of detection is adjusted (FIG. 25).

  For example, when the sheet material information detectable time t is shorter than a preset time, the rising amount of the sheet material gripping member 151 is increased and the sheet material P of the sheet material P by the sheet material gripping member 151 and the upper sensor unit holding member 103 is increased. Increase gripping force.

  Thereby, it becomes difficult to pull out the sheet material P from the sheet material determination apparatus 100 as the gripping force is increased. Therefore, it becomes possible to earn the sheet material information detectable time t, and the sheet material information detection sensor 110 can detect the sheet material information for a predetermined number of times set in advance. It becomes possible.

  Conversely, when the sheet material information detectable time t is longer than a preset time, the gripping force of the sheet material P by the sheet material gripping member 151 and the upper sensor unit holding member 103 may be too large. For this reason, the sheet material gripping member 151 is positioned below the detection position when the previous sheet material information detection procedure was not performed normally, and the sheet by the sheet material gripping member 151 and the upper sensor unit holding member 103 is used. The gripping force of the material P is weakened (FIG. 26).

  As a result, the sheet material P is easily pulled out from the sheet material determination apparatus 100 as the gripping force is weakened. Therefore, the sheet material P can be prevented from stopping when the sheet material information is detected, and the sheet material information detection sensor 110 is prevented from acquiring the sheet material information from the same portion of the sheet material P a plurality of times. The accuracy can be increased.

  Therefore, if the detection of the sheet material information is not normally performed and the error display lamp 120 is lit in red, based on the sheet material information detected by the sheet material information detection sensor 110, the sheet material information detectable time t, and the like, An adjustment amount of the position of the sheet material gripping member 151 is obtained (S15).

  Thereafter, when the sheet material information is re-detected by the same procedure as described above, the cams 152 and 153 are rotated by the driving force from the drive generator 155 based on the adjustment amount, and the sheet material is detected. The gripping member 151 is moved to the target position at the time of redetection. Then, the sheet material P is gripped by the sheet material gripping member 151 and the upper sensor unit holding member 103.

  As a result, it is possible to adjust the drawing speed of the sheet material P from the sheet material determination apparatus 100 by the operator so that an appropriate sheet material information detectable time t is obtained.

  On the other hand, when the sheet material information detectable time t is longer than the reference time t1 and shorter than the reference time t2 (NO in S11), it is determined that the sheet material information is normally detected, and the detected sheet material P is detected. Based on the information, the control unit 600 determines the sheet material P (S13).

  Thus, an appropriate sheet material in which the sheet material information is detected a plurality of times from the same portion of the sheet material P while the sheet material information detection sensor 110 performs a predetermined number of times of preset sheet material information detection. Based on the information, it is possible to determine the sheet material P with high accuracy.

[Configuration example 3]
FIG. 27 is a schematic configuration diagram of a sheet material discrimination device 100 according to Configuration Example 3. Since the basic configuration of the sheet material determination apparatus 100 according to the configuration example 3 is the same as that of the sheet material determination apparatus 100, the description thereof is omitted.

  In the sheet material determination device 100 according to the configuration example 3, a sheet material thickness detection sensor 170 that detects the thickness of the sheet material P inserted into the gap is provided. Further, the detection of the sheet material information by the sheet material information detection sensor 110 is finished by detecting the sheet material information a predetermined number of times set in advance within a predetermined time from the start of the detection of the sheet material information.

  FIG. 28 is a schematic configuration diagram of the sheet material thickness detection sensor 170 installed in the sheet material determination apparatus 100. The sheet material thickness detection sensor 170 is an encoder serving as a displacement amount detection unit that detects a displacement amount according to the paper thickness. And as shown in FIG. 28, it has the filler 171 which formed the several slit 171b with the pitch of a fixed angle, and the transmissive | pervious optical sensor 172 which detects the slit 171b of this filler 171.

  When the sheet material P is not inserted into the gap of the sheet material determination apparatus 100, the filler 171 is located at the initial position where the upper end 171a of the filler 171 contacts the lower surface 103a of the upper sensor unit holding member 103.

  When the sheet material P is inserted into the gap of the sheet material discriminating apparatus 100, the sheet material P is interposed between the filler 171 pushed by the sheet material P and rotated about the rotation shaft 173 and the upper sensor unit holding member 103. Sandwiched.

  Then, the amount of rotation of the filler 171 at this time is obtained by detecting the slit 171b passing through the position facing the sensor portion 172a of the optical sensor 172 by the optical sensor 172. The thickness of the sheet material P is detected by converting the rotation amount thus obtained into a thickness amount by a predetermined arithmetic expression or the like.

  Here, when thick paper is used as the sheet material P, the gripping force of the sheet material P by the sheet material gripping member 151 and the upper sensor unit holding member 103 is large, and the sheet material P is pulled out from the sheet material discrimination device 100. It becomes difficult. For this reason, when thick paper is used as the sheet material P, the sheet material information detectable time t tends to be longer than when thin paper or plain paper is used.

  Therefore, when the same determination condition as that of thin paper or plain paper is used as the determination condition as to whether or not the detection of the sheet material information is performed normally, which is compared with the sheet material information detectable time t as described in the configuration example 2. The sheet material information is re-detected more than necessary, and workability may be reduced.

  Therefore, in this configuration example, the control unit 600 determines whether or not the detection of the sheet material information has been normally performed based on the thickness of the sheet material P detected by the sheet material thickness detection sensor 170. It can be changed. That is, when thick paper is used as the sheet material P, the determination condition as to whether or not the detection of the sheet material information has been normally performed is changed to a reference time t2 'that is longer than the reference time t2. The reference time t1 is not changed.

  When the sheet material information detectable time t is shorter than the reference time t1 or when the sheet material information detectable time t is longer than the reference time t2 ′, the sheet material information is not normally detected. This is determined by the control unit 600. On the other hand, when the sheet material information detectable time t is longer than the reference time t1 and shorter than the reference time t2 ', the control unit 600 determines that the sheet material information has been normally detected.

  Thus, when thick paper is used as the sheet material P, the sheet material information is detected a predetermined number of times set in advance while reducing the frequency of re-detection of the sheet material information and suppressing deterioration in workability. Thus, the sheet material P can be determined with high accuracy.

What has been described above is merely an example, and the present invention has a specific effect for each of the following modes.
(Aspect A)
Information detection means such as a sheet material information detection sensor 110 that detects information on a sheet material such as the sheet material P, and determination means such as a control unit 600 that determines the sheet material based on information on the sheet material detected by the information detection means And at least a part of the sheet material is positioned at an information detectable position such as a sheet material information detectable position X, which is a position where the information of the sheet material can be detected by the information detection means in the apparatus. A sheet material discriminating apparatus such as a sheet material discriminating apparatus 100 that is used by being positioned outside the image forming apparatus, wherein the sheet material is moved relative to each other and the sheet material information is detected at a plurality of locations on the sheet material by the information detecting means. When it is possible to detect the sheet material information detectable time t when the sheet material information can be detected by the information detection means on the sheet material that moves relative to the apparatus. When the detectable time detection means such as the control unit 600 for detecting the detection time and the detectable time detected by the detectable time detection means are shorter than a first reference time such as a preset reference time t1, the seat And control means such as a control unit 600 for controlling the discriminating means so as not to discriminate the material.
In (Aspect A), the number of detections of the sheet material information by the information detection unit can be secured so that the number of samples of the sheet material information can be obtained so that the determination of the sheet material by the determination unit can be performed with high accuracy. Time is preset as the first reference time. As a result, when the detectable time detected by the detectable time detection means is shorter than the first reference time, the number of times of detection cannot be ensured, and the determination of the sheet material by the determination means is performed with high accuracy. The number of sheets of sheet material information that can be done is not obtained. Therefore, when the detectable time is shorter than the first reference time, the control unit controls the determination unit so as not to determine the sheet material, so that the accuracy is low due to the insufficient number of samples of the sheet material information. It is possible to prevent the sheet material from being discriminated. Therefore, it is possible to suppress an inappropriate image forming condition not depending on the type of the sheet material from being set by the image forming apparatus based on the determination result of the sheet material with low accuracy.
(Aspect B)
In (Aspect A), the detectable time detection means starts detection of sheet material information by the information detection means at a predetermined timing with respect to a sheet material at least partially located at the information detectable position, It has measuring means such as a timer for measuring a passing time until the sheet material has passed through the information detectable position, and detects the passing time measured by the measuring means as the detectable time. According to this, as described in the above embodiment, when the passage time measured by the measuring unit is shorter than the first reference time, the number of times of detection cannot be secured, and the determining unit The number of samples of sheet material information that can accurately determine the sheet material is not obtained. Therefore, when the passage time is shorter than the first reference time, the control unit controls the determination unit so as not to determine the sheet material, so that the sheet with low accuracy due to the insufficient number of samples of the sheet material information. It is possible to prevent the material from being discriminated. Therefore, it is possible to suppress an inappropriate image forming condition not depending on the type of the sheet material from being set by the image forming apparatus based on the determination result of the sheet material with low accuracy.
(Aspect C)
In (Aspect B), the control means is longer than a second reference time such as a preset reference time t2, which is a time longer than the first reference time, measured by the measuring means. Even in this case, the determination means is controlled so as not to determine the sheet material. According to this, as described in the above embodiment, it is possible to prevent the determination of the sheet material with low accuracy based on the sheet material information detected a plurality of times at the same position of the sheet material.
(Aspect D)
In (Aspect B) or (Aspect C), sheet position restriction means such as a stopper 8 for restricting the position of the sheet material, and sheet material position detection for detecting the presence or absence of the sheet material at a restriction position by the sheet material restriction means. A sheet position detecting means such as a sensor 9 and when it is detected by the sheet material position detecting means that there is no sheet material at the restriction position from the state where the sheet material is detected at the restriction position. Then, detection of sheet material information by the information detection means is started, and the measurement means measures the passage time using detection results of the sheet material position detection means and the information detection means. According to this, as described in the above embodiment, the passage time can be obtained with high accuracy.
(Aspect E)
In (Aspect A) to (Aspect D), the information detecting unit detects information on the sheet material by receiving light emitted from a light emitting unit such as the light source 111 on the surface of the sheet material and receiving the light by a plurality of light receiving units. The light receiving means includes at least transmitted light light receiving means such as a light receiver 160 that receives light transmitted through the sheet material among light emitted from the light emitting means. According to this, as described in the above embodiment, it is possible to determine the sheet material with higher accuracy.
(Aspect F)
In (Aspect A) to (Aspect E), the information detecting means receives light emitted from a light emitting means such as a light source 111 on the surface of the sheet material by a plurality of light receiving means and receives information on the sheet material. As the light receiving means, reflected light polarization component light receiving means such as light receivers 114 and 118 for receiving the polarization component of the light reflected from the sheet material out of the light emitted from the light emitting means. at least. According to this, as described in the above embodiment, a detection result with higher accuracy can be obtained.
(Aspect G)
In (Aspect A) to (Aspect F), it is possible to determine the brand of the sheet material based on the detection result of the information detection means.
(Aspect H)
In (Aspect A) to (Aspect F), it is possible to determine at least one of the thickness and the surface state of the sheet material based on the detection result of the information detection means.
(Aspect I)
In (Aspect B) to (Aspect H), information detection quality determination means such as a control unit 600 that determines quality of sheet material information detection by the information detection means based on the passage time measured by the measurement means. Have. According to this, as described in the above embodiment, it is possible to perform highly accurate determination of the sheet material based on the appropriate sheet material information in which the detection of the sheet material information has been normally performed.
(Aspect J)
(Aspect I) includes a display unit such as an error display lamp 120 that displays the quality of sheet material information detection based on the determination result of the information detection quality determination unit. According to this, as described in the above embodiment, the operator can easily grasp that the detection of the sheet material information has not been normally performed, and can prompt the re-detection of the sheet material information.
(Aspect K)
In (Aspect I) or (Aspect J), the determination condition used for the quality determination of sheet material information detection by the information detection quality determination means is changed according to the thickness of the sheet material. According to this, as described in the above embodiment, it is possible to determine the sheet material with high accuracy while reducing the frequency of re-detection of the sheet material information and suppressing deterioration in workability.
(Aspect L)
In (Aspect A) to (Aspect K), the detection interval of the sheet material information by the information detection means can be arbitrarily changed. According to this, as described in the above embodiment, it is possible to detect sheet material information at appropriate detection intervals.
(Aspect M)
In (Aspect A) to (Aspect L), a sheet material placing portion such as a sheet material grasping member 151 on which the sheet material is placed, and an elevating means such as a sheet material grasping mechanism 150 for raising and lowering the sheet material placing portion. The sheet material is inserted between the sheet material placing portion and the information detection means, and the sheet material information is detected by the information detection means. According to this, as described in the above embodiment, the sheet material placement portion is raised to restrain the sheet material from fluttering and the like, and the detection operation of the sheet material information by the information detection unit is stabilized. be able to.
(Aspect N)
In (Aspect M), the ascending / descending position of the sheet material placing portion by the elevating means can be adjusted. According to this, it becomes possible to adjust the drawing speed of the sheet material and the like.
(Aspect O)
In (Aspect N), the elevating means can adjust the elevating position by electric control. According to this, the adjustment of the raising / lowering position can be simplified.
(Aspect P)
In (Aspect M) to (Aspect O), the elevating means can adjust the elevating position based on the detection result of the information detecting means. According to this, as described in the above embodiment, the sheet material information can be normally detected when the sheet material information is re-detected.
(Aspect Q)
In (Aspect M) to (Aspect P), the presence / absence of the sheet material at the restriction position by the sheet position restriction means for restricting the position of the sheet material is detected at the timing at which the sheet material placement portion is raised and lowered by the lifting means. Adjustment is made based on the detection result of the sheet position detection means. According to this, as described in the above embodiment, the sheet material is reliably placed in the set state in which the sheet material is positioned at the normal position of the detection start for detecting the sheet material information by the information detection unit. It can be restrained by a mounting portion or the like.
(Aspect R)
In an image forming apparatus including an image forming unit that forms an image on a sheet material, and a sheet material determination device that detects information on the sheet material and determines the sheet material, the sheet material determination device includes: ) To (Aspect Q) are provided outside the image forming apparatus. According to this, as described in the above embodiment, it is possible to suppress the setting of inappropriate image forming conditions not depending on the type of the sheet material in the image forming apparatus, and to perform good image formation. Is possible.
(Aspect S)
In (Aspect R), an image forming condition is set based on the discrimination result of the sheet material discrimination device. According to this, as described in the above embodiment, it is possible to perform image formation under appropriate image forming conditions based on the determination result of the sheet material.

DESCRIPTION OF SYMBOLS 1 Image forming system 2 Image forming apparatus 3 Sheet | seat post-processing apparatus 4 Operation panel 8 Stopper 9 Sheet | seat material position detection sensor 10 1st discharge tray 11 Inlet roller 12 Conveyance roller 13 Conveyance roller 14 Discharge roller 15 Inlet sensor 17 Branching claw DESCRIPTION OF SYMBOLS 20 Conveying roller 21 Conveying roller 22 Conveying roller 23 Sheet material stacking tray 24 First sheet material aligning unit 25 End binding processing unit 26 Branching claw 27 Branching claw 28 First bundling unit 31 Conveying roller 32 Conveying roller 33 Saddle binding folding unit 34 Folding part 35 Saddle stitching processing part 36 Second bundling part 37 Second movable reference fence 38 Folding blade 39 Lower pressing roller 40 Upper pressing roller 41 Paper discharge roller 42 Second paper discharge tray 51 Conveying part 60 Communication cable 100 Sheet Material discrimination device 103 Upper sensor unit holding member 103a Bottom 104 Lower sensor unit holding member 105 Elastic body 106 Elastic body 110 Sheet material information detection sensor 110A Upper sensor unit 110B Lower sensor unit 111 Light source 112 Collimator lens 113 Light receiver 114 Light receiver 115 Light receiver 116 Polarizing filter 117 Polarizing filter 118 Light receiver 119A Dark box 119B Dark box 120 Error display lamp 130 Processing device 131 Light source drive circuit 132 Current-voltage conversion circuit 133 AD conversion circuit 150 Sheet material gripping mechanism 151 Sheet material gripping member 152 Cam 153 Cam 154 Drive transmission device 155 Drive generator 160 Light receiver 170 Sheet Material thickness detection sensor 171 Filler 171a Upper end 171b Slit 172a Sensor unit 172 Optical sensor 173 Rotating shaft 300 Image reading device 3 DESCRIPTION OF SYMBOLS 1 Light source 302 Mirror 303 1st traveling body 304 Mirror 305 Mirror 306 2nd traveling body 307 Lens 309 Platen glass 400 Image forming apparatus main body 401 Photosensitive drum 402 Charging device 404 Developing device 405 Transfer device 406 Cleaning device 407 Fixing device 410 Exposure device 411 Laser unit 412 Polygon mirror 413 Registration roller pair 414a Feed roller 414b Feed roller 500 Automatic document feeder 501 Document table 502 Document separation feed roller 503 Conveyor belt 504 Document discharge tray 600 Controller

JP 2007-233186 A

Claims (20)

Information detecting means for detecting information on the sheet material;
A discriminating means for discriminating a sheet material based on information on the sheet material detected by the information detecting means,
In a state where at least a part of the sheet material is positioned at an information detectable position, which is a position where the information of the sheet material can be detected by the information detecting means in the apparatus, the information detecting means moves the sheet material relative to the apparatus. A sheet material discriminating device that is used by being positioned outside the image forming apparatus, detecting sheet material information at a plurality of locations on the sheet material,
Detectable time detection means for detecting the detectable time when the sheet material information can be detected by the information detection means on the sheet material that moves relative to the apparatus;
Control means for controlling the discrimination means so as not to discriminate the sheet material when the detectable time detected by the detectable time detection means is shorter than a preset first reference time. The sheet | seat material discrimination device characterized by the above-mentioned. In the sheet | seat material discrimination | determination apparatus of Claim 1,
The detectable time detecting means detects the information detectable position after the detection of the sheet material information by the information detecting means is started at a predetermined timing with respect to a sheet material at least partially located at the information detectable position. It has a measuring means to measure the passage time until the sheet material finishes passing,
The sheet material discriminating apparatus, wherein the passage time measured by the measuring means is detected as the detectable time. In the sheet material discrimination device according to claim 2,
The control means does not determine the sheet material even when the passing time measured by the measuring means is longer than a preset second reference time that is longer than the first reference time. The sheet material discriminating apparatus characterized by controlling the discriminating means as described above. In the sheet | seat material discrimination | determination apparatus of Claim 2 or 3,
Sheet material regulating means for regulating the position of the sheet material ;
Sheet material position detection means for detecting the presence or absence of the sheet material at the restriction position by the sheet material restriction means,
When it is detected that there is no sheet material at the restriction position from the state where the sheet material position detection means detects that there is a sheet material at the restriction position, detection of the sheet material information by the information detection means is started,
The sheet measurement apparatus according to claim 1, wherein the measuring unit measures the passage time using detection results of the sheet material position detection unit and the information detection unit. In the sheet material discriminating device according to claim 1, 2, 3, or 4,
The information detecting means detects the information of the sheet material by receiving light emitted from the light emitting means on the surface of the sheet material by a plurality of light receiving means, and as the light receiving means, from the light emitting means An apparatus for discriminating sheet material, comprising at least transmitted light receiving means for receiving light transmitted through the sheet material among the irradiated light. In the sheet material discriminating apparatus according to claim 1, 2, 3, 4 or 5,
The information detection means is for detecting information of the sheet material by receiving light emitted from the light emitting means on the surface of the sheet material with a plurality of light receiving means,
The sheet material discriminating apparatus comprising at least reflected light polarization component light receiving means for receiving a polarization component of light reflected from the sheet material, out of light emitted from the light emitting means, as the light receiving means. In the sheet material discrimination device according to claim 1, 2, 3, 4, 5 or 6,
The sheet material discrimination device, wherein a brand of the sheet material is determined based on a detection result of the information detection means. In the sheet material discrimination device according to claim 1, 2, 3, 4, 5 or 6,
A sheet material discrimination device that determines at least one of a thickness and a surface state of the sheet material based on a detection result of the information detection means. The image forming apparatus according to claim 2, 3 or 4 .
A sheet material discriminating apparatus comprising: an information detection pass / fail judgment means for judging pass / fail of sheet material information detection by the information detection means based on the passage time measured by the measurement means. In the sheet material discriminating device according to claim 9,
A sheet material discriminating apparatus, comprising: a display unit configured to display the quality of sheet material information detection based on a determination result of the information detection quality determination unit. In the sheet material discrimination device according to claim 9 or 10,
A sheet material discriminating apparatus, characterized in that a determination condition used for determining whether or not sheet information is detected by the information detection quality determining unit is changed according to a thickness of the sheet material. In the sheet material discrimination device according to claim 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 or 11,
The sheet material discriminating apparatus characterized in that the detection interval of the sheet material information by the information detecting means can be arbitrarily changed. In the sheet material discrimination device according to claim 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 or 12,
A sheet material placement section on which the sheet material is placed;
Elevating means for elevating and lowering the sheet material placing portion,
A sheet material discriminating apparatus, wherein a sheet material is inserted between the sheet material placing portion and the information detecting means, and the sheet material information is detected by the information detecting means. In the sheet | seat material discrimination | determination apparatus of Claim 13,
The sheet material discriminating apparatus, wherein an elevation position of the sheet material placing portion by the lifting means is adjustable. In the sheet | seat material discrimination | determination apparatus of Claim 14,
The sheet material discriminating apparatus characterized in that the elevating means can adjust the elevating position by electric control. In the sheet material discriminating apparatus according to claim 2, 3, 4, or 9 ,
A sheet material placement section on which the sheet material is placed;
Elevating means for elevating and lowering the sheet material placing portion,
Inserting a sheet material between the sheet material placing portion and the information detection means, detecting the sheet material information by the information detection means,
The lifting position of the sheet material placing portion by the lifting means can be adjusted,
The lifting / lowering means can adjust the lifting / lowering position based on the passage time measured by the measuring means. In the sheet | seat material identification device of Claim 14 or 15,
The lifting / lowering means can adjust the raising / lowering position based on the detection result of the information detection means. In the sheet material discriminating device according to claim 13, 14, 15, 16 or 17,
The timing for raising and lowering the sheet material placing portion by the elevating means is adjusted based on the detection result of the sheet position detecting means for detecting the presence or absence of the sheet material at the restriction position by the sheet position restricting means for restricting the position of the sheet material. The sheet | seat material discrimination | determination apparatus characterized by doing. Image forming means for forming an image on a sheet material;
In an image forming apparatus comprising a sheet material discriminating device that detects information on the sheet material and discriminates the sheet material,
The sheet material discrimination device according to claim 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17 or 18 as the sheet material discrimination device. An image forming apparatus, wherein the apparatus is provided outside the image forming apparatus. The image forming apparatus according to claim 19.
An image forming apparatus, wherein an image forming condition is set based on a determination result of the sheet material determining apparatus.

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