JP2005351676A - Sheet material information detector and sheet material processor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sheet material information detector for efficiently detecting information on a sheet material while having satisfactory information detection accuracy. <P>SOLUTION: This detector is structured so that a signal owing to external force impressed on the sheet material P by an external force impression means 2 is detected by a signal detection means 3 while frequency components within a specific domain included in an output signal input from the detection means 3 are removed or extracted by a filter 101, and that a sheet material information detection means 102 detects information on the sheet material P on the basis of an output signal from the filter 101. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a sheet material information detection apparatus and a sheet material processing apparatus that detect information related to a sheet material.

  2. Description of the Related Art In recent years, a sheet material information detection device that detects information related to a sheet material has attracted attention. For example, such a sheet material information detection device is provided in an image forming apparatus that is an example of a sheet material processing device. An apparatus has been proposed in which the type of sheet material is determined by an apparatus (see Patent Document 1).

Japanese Patent Laid-Open No. 2000-301805

  By the way, for example, sheet materials such as sheet materials used in image forming apparatuses are continually diversifying, and even those that are generally used at present are plain paper based on wood fiber, OHP by resin material Film materials such as sheets, and bond paper made by mixing sub-materials such as cotton fibers with wood fibers are enormous.

  On the other hand, in image forming apparatuses, there is an increasing demand for higher image quality and energy saving, and control for changing image forming conditions (print mode) in accordance with sheet material information is in progress. For this reason, it is necessary for the sheet material information detection apparatus to detect the sheet material information with high accuracy and in a short time.

  Therefore, an object of the present invention is to provide a sheet material information detection apparatus and a sheet material processing apparatus that can detect information on a sheet material with high accuracy and efficiency.

  The present invention has been made in consideration of the above circumstances, and in a sheet material information detection apparatus for detecting information on a sheet material, an external force applying means for applying an external force to the sheet material, and the sheet resulting from the external force A signal detection means for detecting a signal from the material, and a filter for removing or extracting a frequency component of a specific region included in the output signal from the signal detection means, and a signal obtained by operating the filter Based on this, information on the sheet material is detected.

  As in the present invention, a frequency component in a specific region included in the output signal from the signal detection means that detects the signal from the sheet material caused by the applied external force is removed or extracted by the filter, and this filter is operated. By detecting the information on the sheet material obtained in this way, the information on the sheet material can be detected accurately and efficiently.

  The best mode for carrying out the present invention will be described below with reference to the drawings.

  FIG. 1 is a diagram showing a configuration of a sheet material information detection apparatus and a sheet material processing apparatus according to an embodiment of the present invention. In FIG. 1, 20 is an external force application member, 2 is a sheet material P by an external force application member 20. An external force applying unit that is an external force applying unit that applies external force to the signal, 3 is a signal detecting unit that is a signal detecting unit that detects a signal output from the sheet material P due to the external force, and 101 is an output from the signal detecting unit 3 A filter that removes or extracts a frequency component in a specific region included in the signal, and 102 is a sheet material information detection unit that is a sheet material information detection unit that detects information about the sheet material P based on an output signal from the filter 101. .

  Reference numeral 4 denotes a sheet material displacement member disposed at a position facing the external force application unit 2 (via the sheet material). The position of the sheet material P when an external force is applied by the sheet material displacement member 4 is indicated. I try to control it.

  FIG. 2 is a diagram for explaining the sheet material information detecting operation in the sheet material information detecting apparatus having such a configuration. When detecting sheet material information, first, an external force is applied to the sheet material (S1). Next, the signal detector 3 detects a signal output as, for example, an electrical waveform from the sheet material due to the external force (S2). Next, the filter 101 removes or extracts a frequency component of a specific region from the detected signal (S3), and based on the detection result (for example, an electric signal), the sheet material information detection unit 102 detects information about the sheet material. Then, for example, it outputs to CPU (not shown) of the sheet material processing apparatus (S4).

  Next, a process of removing or extracting a frequency component in a specific region from the signal detected by the signal detection unit 3 using the filter 101 will be described.

  FIG. 3 is a diagram for explaining the handling of signals according to the present invention. The external force application member 20 having a certain mass collides with the sheet material at a predetermined speed as an external force by using the sheet material information detection apparatus of the present embodiment. In this example, an electrical output waveform from the signal detector 3 (which is a piezoelectric element in the present embodiment) and an output waveform subjected to frequency analysis by fast Fourier transform (hereinafter referred to as FFT) are shown.

  3A is an example of output waveforms when there are no typical three types of sheet materials having different qualities, and FIG. 3B is an example of output waveforms obtained by FFT. It is an example converted into a signal level corresponding to a frequency component.

  Here, as a sheet material to be detected for detecting information, plain paper (XEROX 4024 (75 g) hereinafter referred to as XX75), textured paper (NEENAH Paper CLASSIC Laid Writing, Kimberly-Clark Corporation) The following three are used: NCL75) and OHP sheet (Sumitomo 3M CG3300, hereinafter referred to as OHP).

  FIG. 3A shows the three types of sheet material and the output waveform when there is no sheet material overlaid (for ease of viewing, the time position of the peak is shifted and graphed). As is clear from this figure, the output waveform from the signal detection unit 3 appears as a voltage peak corresponding to the application of external force, and varies depending on the presence or absence of the sheet material and the type of the sheet material.

  When the FFT analysis is performed on each of such waveforms, the signal level varies greatly depending on the sheet material, particularly in the frequency range of 2 kHz to 10 kHz. Therefore, in the present embodiment, information on the sheet material is obtained by removing or extracting a frequency component of a specific region from the signal detected by the signal detection unit 3 and detecting a difference in signal level in such a frequency region. Is efficiently detected.

  Although any means can be used as means for removing or extracting a frequency component in a specific region from the detected signal, an electrical filter (101 in FIG. 1) is preferably used. Here, as the filter, a low-pass filter or a high-pass filter having a predetermined cut-off frequency and a band-pass filter having a predetermined pass band are preferably used.

  Of course, the output waveform from the signal detector 3 varies depending on not only the sheet material but also the external force to be applied and the characteristics of the signal detector 3, especially these materials and dimensions. Depending on the type, it is necessary to select an appropriate filter design value (cutoff frequency, passband, attenuation, etc.).

  On the other hand, when a metal material (stainless steel, etc.) is used as a member that contacts the sheet material, such as the external force application member 20, and the paper or OHP sheet is targeted as the sheet material, the signal in the frequency region described above is generally extracted. It is effective to do. For this reason, the pass band of the filter should be 2 kHz to 10 kHz, more preferably about 4 kHz to 7 kHz.

  And the information of a sheet | seat material is efficiently detectable by comparing the level of the signal after such a filter passage. As will be described later, when a plurality of different external forces are applied, it is needless to say that a passband filter suitable for the output obtained corresponding to each of them is used.

  By the way, detection of information regarding the sheet material may be performed by a person based on the detection result, or may be automatically performed based on inputting the detection result to the sheet material information detection unit 102. Here, the sheet material information detection unit 102 described above may detect the information on the sheet material by comparing the detection result of the signal detection unit 3 with the data.

  That is, the sheet material information detection unit 102 obtains these detection results (signals) in advance and is stored in a memory unit (not shown), and the type, model number, and state of the sheet material corresponding to the output signal and the output signal. The information such as change, print state, and multi-feed may be compared with the recorded data table and output as information for determining the sheet material.

  When the signal of the sheet material differs depending on the environmental conditions, the conveyance state, etc., it is preferable to prepare a plurality of tables corresponding to each and make a determination based on the prepared tables. In addition, when a plurality of signal detection units 3 are provided, or when signal detection is performed a plurality of times by changing an external force application condition, a corresponding data table may be provided.

  Furthermore, another means regarding the sheet material (for example, input of an artificially set paper model number or a signal from a separately provided sensor) may be determined together. Furthermore, it is also preferable to provide a logic circuit for making a determination by combining the plurality of detection results and determination results.

  Further, for example, signal processing such as subtracting an output signal when the sheet material is not conveyed may be performed on the detected signal. The processing circuit that performs such signal processing includes the first signal when the signal detection unit receives the external force when the sheet material is not sandwiched, and the external force when the sheet material is sandwiched. Signal processing can be performed using the second signal received by the detection unit.

  By the way, in the present embodiment, the sheet material means a recording medium (for example, plain paper, glossy paper, coated paper, recycled paper, OHP, etc.) or a document. “Information about sheet material” refers to the type of sheet material, model number, density of sheet material, thickness of sheet material, irregularities on the surface of sheet material, state change of sheet material, printing status, It means the presence / absence of feeding, the number of sheets to be fed, the remaining number, the presence / absence of sheet material, the overlapping position of sheet material, and the like.

  In particular, the present invention is effective in detecting information that exhibits a characteristic behavior as a frequency component, such as vibration characteristics of a sheet material and a periodic structure in surface irregularities. Examples of such materials include the material, rigidity, dimensions, uneven period (including those that are intentionally formed as texture in the paper making process), repulsion, and the like.

  On the other hand, the external force application unit 2 includes an external force application member 20 (see FIG. 1) that applies an external force to the sheet material based on contact with the sheet material, or a configuration that blows a gas such as air. good. The external force application member 20 is preferably driven by a drive source.

  Further, the external force used in this embodiment may be any electromagnetic force, heat or heat expansion / contraction of a medium such as a gas, light such as laser light, electromagnetic wave, sound wave, vibration, mechanical force, etc. Can be used. Furthermore, the external force may be applied as an impact force, but may be applied as vibration.

  As a drive source in the case of applying an impact force, the external force applying member 20 is held above the sheet material P, and the external force applying member 20 can be appropriately dropped on the sheet material P, mechanically or An example in which the external force applying member 20 is caused to collide with electromagnetic energy (for example, a mechanical means such as a spring, an electromagnetic means such as a solenoid or a voice coil) can be given, and a preferable example is a motor or From the viewpoint of stability, it is also preferable to use the rotational force of a roller or the like used in the sheet material conveyance system after changing the direction and size by a conversion mechanism such as a gear or a cam.

  In addition, as a drive source in the case of applying vibration, an excitation means (for example, a piezoelectric actuator, an electrostatic actuator, or an electromagnetic sound generator) that vibrates the external force application member 20 can be used.

  Further, when applying an impact force, not only the method of causing the external force application member 20 to collide with the sheet material P from a distant position, but also the state in which the external force application member 20 is in contact with the sheet material P from the external force application member 20. A method of applying an impact force to the sheet material P can also be taken.

  That is, the external force application by the external force application member 20 is performed in a state where the external force application member 20 is in contact with the sheet material P. However, even if the external force application member 20 is in contact with the sheet material P only when the external force is applied, the external force is applied. The external force applying member 20 may already be brought into contact with the sheet material P before applying.

  In the case of the former, and when the external force application member 20 and the signal detection unit 3 are opposed to each other through the sheet material, the external force application member 20 and the signal detection unit 3 The distance of will change (become shorter). Further, when a force is applied to the sheet material by the external force application member 20 (external force application means 2), the sheet material may be slightly deformed (can be indented), so the external force is applied to the end of the sheet material, etc. It is good to apply.

  By the way, the application of the external force as described above may be performed on the sheet material being conveyed or may be performed on the sheet material being temporarily stopped. Here, when an external force is applied to the sheet material being conveyed as in the former, there is an advantage that it is easy to detect the surface state of the surface of the sheet material (external force application unit side) in a short time. When applying external force to a sheet material that has been temporarily stopped as in the latter case, there is a merit that detection can be performed accurately as much as there is no noise associated with conveyance of the sheet material. It may be selected as necessary.

  Further, as described above, there are a plurality of types of external forces, but only one type of external force may be used or a plurality of types of external force may be used. Further, when one type of external force is used, information on the sheet material may be detected by applying the external force only once, or information on the sheet material may be detected by applying the external force multiple times.

  Here, when external force application is performed a plurality of times, for example, when one type of external force is applied a plurality of times, or when a plurality of types of external force are applied, a plurality of data is obtained, so that the identification accuracy is higher. Become. Such multiple times of external force application may be performed by one external force application member or multiple external force application members, and the strength of the external force (impact force or vibration strength) may be equal. It may be different. In addition, when the external force is applied a plurality of times as described above, it is preferable to apply the next external force after the vibration of the sheet material due to the applied external force is sufficiently damped or after a predetermined value or less.

Furthermore, the following are mentioned as a preferable aspect at the time of performing external force application in multiple times.
・ Multiple impacts with different impact speeds ・ Vibrations with different frequency components By applying such external force, it is possible to efficiently reflect the difference in viscoelasticity of the polymer sheet material in the output signal. More detailed information on the sheet material can be output. In addition, when such external force application is performed a plurality of times, a plurality of pieces of information can also be output from the signal detection unit 3.

  By the way, in order to accurately detect information, a member (hereinafter referred to as “external force receiving member”) may be disposed at a position facing the external force applying member 20 with the sheet material P interposed therebetween so as to receive the external force. .

  When the sheet material displacement member 4 is disposed so as to face the external force application member 20 (see FIG. 1), the sheet material displacement member 4 may function as an external force receiving member, that is, a separate external force receiving member. However, when the sheet material displacement member 4 is disposed at a position not facing the external force application member 20, the external force receiving member is disposed at a position facing the external force application member 20. Should be provided. In such a sheet material displacement member 4 (external force receiving member), the contact surface with the sheet material may be a flat surface or a curved surface.

  In addition, by providing a recess in the sheet material displacement member 4 (external force receiving member) at a position facing the tip of the external force application member 20 via the sheet material, it is possible to disperse the concentration of external force at one point. It is preferable in terms of element lifetime. By providing such a recess, it is possible to detect the absorption of external force due to the sheet material being bent into the recess by applying an external force, which is a preferable example.

  The sheet material displacement member 4 (external force receiving member) described above may have any structure as long as the sheet material can be displaced. For example, the sheet material may be displaced via a buffer layer such as air, or the sheet material may be displaced by projecting a displacement member into the sheet material conveyance path and contacting the sheet material. . However, when the sheet material displacement member 4 is also used as an external force receiving member, the latter needs to be used.

  Even if the sheet material displacement member 4 (external force receiving member) defines the position of the sheet material with respect to the signal detection unit 3 (that is, the interval between the sheet material P and the signal detection unit 3), Even if the position of the sheet material (that is, the distance between the sheet material P and the external force applying member 20) is defined, the position of the sheet material with respect to the external force receiving member (that is, the distance between the sheet material P and the external force receiving member) is defined. May be.

  When the position of the sheet material relative to the sheet material displacement member 4 (external force receiving member) is defined, the amount of bending of the sheet material due to the application of the external force is made constant, and the external force absorption amount thereby made constant. Therefore, stable detection can be performed with respect to the applied external force. More preferably, the sheet material P is brought into contact with the external force receiving member by the sheet material displacement member 4. For such control, the external force receiving member is pressed against the conveyed sheet material. Or it can also be set as the structure which gives the displacement of the direction which presses down a sheet material with respect to an external force receiving member by the sheet material displacement means 4. FIG.

  It is also preferable to provide a limiting member that limits a region where the sheet material is displaced when an external force is applied. FIG. 4 shows an example of a sheet material information detection apparatus provided with such a restriction member 301. In this case, when the sheet material P is displaced to a predetermined position by the sheet material displacement member 4, the restriction member is shown. It is preferable to press the sheet material P to 301. Reference numeral 41 denotes a pressing roller for pressing the sheet material P against the restricting member 301 as described above. The pressing roller 41 is urged toward the sheet material by a spring 42.

  Here, the limiting member 301 is provided with a hole 302 having a predetermined shape. As a more preferable aspect, the sheet material displacement member 4 (external force receiving member) is provided in the hole 302 of the restriction member 301, and the upper surface of the sheet material displacement member 4 is set to a predetermined depth d from the upper surface of the hole 302 of the restriction member. Place it in a position that is retracted only.

  And by setting it as such arrangement | positioning, when the external force with respect to the sheet | seat material P is applied, a deflection | deviation is generated in the sheet | seat material P, and the difference in the behavior of this deflection | deviation by the state of the sheet | seat material P is detectable. As an example, with the compression coil spring 303 or the like as a drive source, the external force applying member 20 is caused to collide with the sheet material P with a certain stroke amount (first collision), and further, the sheet material P is deflected by the collision (deflection process). In addition, an external force is applied in a step of causing the sheet material displacement member 4 to collide (second collision).

  In such a process, the speed (V1) of the external force application member 20 at the time of the first collision is decelerated by the sheet material P in the bending process. Since the amount of deceleration varies depending on characteristics such as the thickness and material of the sheet material P, the speed (V2) at the time of the second collision reflects information on the sheet material P. For this reason, if the signal detection part 3 is provided in the sheet material displacement member 4, the output will depend on V2 reflecting the information of the sheet material.

  In the case of this configuration, it is particularly effective in detecting the deflection rigidity of the sheet material P and information related thereto, for example, the sheet material thickness, material, density, sheet material tension, water content, etc. It is possible to detect the stiffness change due to.

  A preferable range of d and W is a range of about 0.1 mm <d <2.0 mm and 5 mm <W <20 mm. In this range, a recording medium (for example, plain paper, glossy paper, coated paper) , Recycled paper, OHP, etc.) can be suitably detected.

  It is also preferable that a sheet material sensor for detecting the state and position of the sheet material P (interaction between the external force application unit 2 and the signal detection unit 3 and the sheet material) is added. Here, “the state and position of the sheet material P (the interaction between the external force application unit 2 and the signal detection unit 3 and the sheet material)” refers to the contact state between the external force application unit 2 and the signal detection unit 3 and the sheet material. It means the tip position of the sheet material, the passing state of the sheet material, the pressure received by the external force application unit 2 and the signal detection unit 3 from the sheet material, the deformation of the sheet material, and the like.

  Examples of the sheet material sensor include a mechanical sensor and an optical sensor that detect contact and deformation, a pressure sensor that detects pressure, and an acceleration sensor that detects vibration. Such a sheet material sensor may be directly joined to the external force application unit 2 or the signal detection unit 3 or may be installed in the vicinity of the external force application unit 2 or the signal detection unit 3. It can be designed accordingly.

  By feeding back the signal from the sheet material sensor, it is possible to optimize the control of the external force application unit 2 and the signal detection unit 3 and to detect sheet information with higher accuracy. In addition, conditions such as timing and intensity of the start / end of external force application can be determined based on the signal from the sheet material sensor.

  Further, the interaction between the external force application unit 2 and the signal detection unit 3 and the sheet material, for example, the pressure from the sheet material, the deformation of the sheet material, and the like are detected and combined with the signal by the external force application of the present embodiment. If used, more information on the sheet material can be obtained.

On the other hand, the signal detection unit 3 described above may be composed of an inorganic material or an organic material having piezoelectric characteristics. Specifically, PZT (lead zirconate titanate), PLZT, BaTiO ₃ , PMN-PT (Pb (Pb ( _{mg1 / 3Nb2 / 3) O 3} -PbTiO 3) may be composed of an inorganic material or an organic piezoelectric material, such as. By using such a piezoelectric material, the external force is detected as a voltage signal.

  The position where the signal detection unit 3 is disposed may be any position as long as a signal caused by an external force can be detected. For example, as illustrated in FIGS. 1 and 4, the external force application unit 2 with the sheet material P interposed therebetween. Or a position on the external force application unit 2 side.

  In the case of FIG. 4, since the signal detection unit 3 supports the sheet material displacement member 4 as an external force receiving member, the signal detection unit 3 detects the external force received by the sheet material displacement member 4. . And when arrange | positioning in this way, the output from the sheet | seat material P with respect to the applied external force can be detected efficiently.

  Further, when the signal detection unit 3 is provided on the external force application unit 2 side, an elastic member (not shown) such as a leaf spring is attached to the external force application unit 2 so that vibration of the elastic member at the time of external force application or Examples include a device that detects a change in position, and a device in which a signal detection unit is mounted on the external force application unit itself.

  And when arrange | positioning in this way, the repulsion of the sheet | seat material with respect to the applied external force can be detected efficiently. In addition, you may arrange | position a signal detection part on both the side which opposes the external force application part 2 on both sides of the sheet material P, and the external force application part 2 side. In addition, when a signal detection unit is mounted on the external force application unit 2, changes in the external force application unit itself (for example, resonance frequency, deformation, etc.) may be detected when contacting the sheet material. Furthermore, it also includes detecting reverberation remaining after the external force applied is stopped, its attenuation characteristics, and the like.

  The signal detection unit 3 may be a one-dimensional array or a two-dimensional array. In the latter case, the signal detection unit 3 includes a sensor unit having a length equal to or longer than the width of a sheet material (for example, a recording medium). If so, the width of the sheet material can also be detected. Of course, the width of the recording medium can be detected by a plurality of sensor units.

  As described above, the filter 101 removes or extracts the frequency component of a specific region included in the output signal from the signal detection unit 3 that has detected the signal from the sheet material P caused by the external force applied to the sheet material P. Then, based on the output signal from the filter 101, in other words, the information regarding the sheet material P is acquired (detected) by operating the filter 101 to detect the information on the sheet material P with high accuracy and efficiency. Can do.

  By the way, the sheet material processing apparatus according to the present embodiment is based on the detection result of the sheet material information detection apparatus indicated by B in FIG. 1 and the sheet material information detection apparatus B, that is, taking the detection result into consideration. And a sheet material processing unit C that performs processing of P.

  Here, examples of the sheet material processing unit C include an image forming unit that forms an image, a scanner unit that reads an image, and other devices. The sheet material processing unit C includes the sheet material processing unit C. Examples of the sheet material processing apparatus include a copying machine, a printer, a FAX, an image reading scanner, and an automatic document feeder.

  Then, based on the detection result of the sheet material information detection apparatus B, a CPU (control unit) (not shown) provided in the sheet material processing apparatus changes the print mode (for example, adjustment of image forming conditions and transfer to a roller used for conveyance). It is preferable to adjust transport conditions such as adjusting the pressing force, stop printing, stop transport of the recording medium, and generate a warning signal. That is, based on the detection result of the sheet material information detection apparatus B, it is preferable to select and execute a process corresponding to the detection result from a plurality of processes. Here, as the CPU, a CPU provided inside or outside the sheet material processing apparatus may be used. However, when a CPU provided inside is used, data from the outside is used. Transmission and reception of signals can be omitted.

(Example)
Hereinafter, the present invention will be described in more detail with reference to examples.

  In this example, a paper type detection device (sheet material information detection device) having the structure shown in FIG. 1 was produced and mounted on an electrophotographic device (sheet material processing device).

  Here, in this paper type detection apparatus, a sheet material conveyance path A is formed by a pair of conveyance guides 10a and 10b, and a conveyance roller (sheet material conveyance means) that conveys the sheet material P is formed in the sheet material conveyance path A. ) 1a, 1b, 1c, 1d are arranged. Reference numeral 11 denotes a sheet material sensor disposed in the vicinity of the roller 1a, and the sheet material sensor 11 detects displacement such as passage of the sheet material P or skew.

  An external force application unit 2 and a signal detection unit 3 are disposed between the rollers 1a and 1b and the rollers 1c and 1d. That is, a notch portion is provided in a part of the transport guide 10a, and the bracket 12 is disposed so as to cover the notch portion from below, and the buffer member 13, the detection sensor (signal detection means) 3 and the displacement member are disposed on the bracket 12. (Sheet material displacement means) 4 was attached. That is, the detection material 3 is supported by the buffer material 13, the displacement member 4 is supported by the detection sensor 3, and the displacement member 4 is protruded into the conveyance path.

  In this embodiment, the protruding amount of the displacement member 4 is 1/4 of the width of the sheet material conveyance path A (the width in the portion where the displacement member 4 is disposed), and is conveyed in the apparatus of the present embodiment. Any type (paper or OHP sheet) of the sheet material is brought into contact with the displacement member 4. Further, the displacement member 4 is formed of a so-called kamaboko-shaped metal member as shown in the figure, and the surface contacting the sheet material P is a notch portion of the conveyance guide 10a at the upstream end and the downstream end in the sheet conveyance direction. Retreat from the opening surface with respect to the transport path A, and project toward the transport guide 10b at the center. Here, reference numeral 14 denotes a pressing pressure adjuster.

  As another aspect, such a contact surface as a whole is configured to recede downward from the opening surface with respect to the conveyance path A of the cutout portion of the conveyance guide 10a, and the sheet material is bent by applying external force, It is also a preferable example that only the sheet material and the displacement member 4 are in contact with each other.

  The detection sensor 3 has a structure in which PZT (lead zirconate titanate), which is a piezoelectric body, is sandwiched between silver electrodes, and the size of the piezoelectric body is 20 mm long, 5 mm wide, and 0.3 mm thick. In addition, a rubber material is used as the buffer material 13, and the buffer material 13 is disposed between the conveyance guide 10 a and the detection sensor 3, thereby propagating mechanical vibration from the conveyance guide 10 a to the detection sensor 3. And the detection accuracy can be increased.

  By the way, in FIG. 1, the bracket 12 is fixed to the conveyance guide 10a. However, of course, the bracket 12 is not limited to this. If appropriate rigidity and fixing accuracy can be obtained, the bracket 12 can be attached to the bracket 211 on the conveyance guide 10b side. These brackets 12 and 211 may be integrated and attached to the conveyance guide 10b, or may be attached to portions other than the conveyance guides 10a and 10b (for example, a housing or a frame).

  In this embodiment, a paper presser 15 is provided to assist the sheet material P in contact with the displacement member 4. Here, the paper presser 15 is composed of a plate material and a fixing material having elasticity, and can apply a force in a direction in which the sheet material is pressed against the displacement member 4 by the elasticity of the plate material. Although not shown in FIG. 1, the paper presser 15 has a mechanism that moves in conjunction with the application of an external force, and retracts out of the transport path when unnecessary. Further, in the present embodiment, the sheet material and the displacement member 4 are contact types, but this is not necessarily required and may be separated.

  On the other hand, an external force application unit 2 for applying an external force to the sheet material P is disposed at a position facing the displacement member 4. In this embodiment, a notch portion is provided in the transport guide 10b, a bracket 211 is disposed in the notch portion, a substantially cylindrical guide member 215 is attached to the bracket 211, and the guide member 215 is provided inside the guide member 215. A rod 217 was arranged so as to be movable in a direction perpendicular to the sheet material P. A pressing member (external force applying member) 20 is attached to the tip of the rod 217 (sheet material side tip), a hook-like stopper member 214 is provided above the pressing member 20, and the stopper member 214, the guide member 215, and the like. A coil spring 210 was shrunk between the two.

  A motor 213 is attached to the bracket 211, and a cam 212 is attached to the output shaft thereof so that the cam 212 can interfere with a protrusion 218 attached to the end of the rod 217. Reference numeral 216 denotes a pressure release hole for reducing damping caused by air in the guide member.

  The pressing member 20 (rod 217) described above collides with the sheet material P at a predetermined speed and applies an external force by the action of the coil spring 210 and the cam 212. The magnitude of the external force at that time is, for example, the product “mV” of the mass m of the pressing member 20 and the collision speed V if the pressing member 20 is in an unconstrained state, the pressing member 20, the sheet material P, and the external force receiving material. As an example, if it is a normal paper sheet type determination, 0.1 gm / s. To 10 gm / s. A range of the degree is preferably used. In addition, the external force is applied by a plurality of, preferably different external force values, for each signal output. By doing in this way, the information of a sheet material can be detected with higher accuracy.

  In this embodiment, the motor 213 has a two-stage cam 212 with different steps, that is, the cam 212 includes two cams, a larger cam 212a and a smaller cam 212b. The two different external forces can be applied by one rotation by.

  By providing the two cams 212a and 212b as described above, when the motor 213 makes one rotation, for example, the larger cam 212a first interferes with the protruding portion 217 so that the pressing member 20 is integrated with the rod 217 upward. The pressing member 20 collides with the sheet material P integrally with the rod 217 by the spring force of the coil spring 210 at the moment when the cam 212 is unlocked.

  Next, the smaller cam 212b interferes with the protrusion 217, moves the pressing member 20 upward together with the rod 217, and is pressed by the spring force of the coil spring 210 at the moment when the locking of the cam 212b is released. The member 20 collides with the sheet material P integrally with the rod 217.

  In this case, since the contraction distance of the coil spring 210 is different between the larger cam 212a and the smaller cam 212b, the external force applied to the sheet material P is different. In addition, it is also preferable to attach another cam to the drive shaft of the cam 212 (that is, the rotation shaft of the motor) and displace the displacement member and the auxiliary displacement member in conjunction with the application of external force.

  In the present embodiment, the displacement member 4 is disposed at a position facing the pressing member 20, and the displacement member 4 is configured to receive an external force. Further, in this embodiment, before the sheet material is supplied from the tray, data in the case where there is no sheet material is read into the processing apparatus as an initial state. Note that reading of the initial state can be omitted.

  In this embodiment, the frequency component in a specific region is removed or extracted from the output signal from the detection sensor 3 described above. This step is performed by a filter having a predetermined pass band.

  Next, the sheet information detection operation in the present embodiment will be described.

  In this embodiment, the external force applied to the sheet material is a stainless steel steel pressing member 20 having a mass of 4 g and a spring force of 0.4 m / sec. It is accelerated and collided with the sheet material. Further, as a sheet material, plain paper (Xerox Corporation XEROX 4024 (75 g) hereinafter referred to as XX75), textured paper (Kimberly-Clark Corporation NEENAH Paper CLASSIC Laid Writing, hereinafter referred to as NCL75), OHP sheet Three types (Sumitomo 3M Co., CG3300, hereinafter referred to as OHP) were used, and the sheet information detection operation was performed for these three types of sheet materials.

  First, the sheet material P is conveyed by the downstream conveying rollers 1 c and 1 d, and then an external force is applied to the sheet material P by the pressing member 20. Then, the external force is transmitted to the detection sensor 3 as an output signal from the sheet material via the displacement member 4, and accordingly, a signal as shown in FIG. 3A is output from the detection sensor 3.

  Next, the level of the output signal from the detection sensor 3 varies greatly depending on the quality of the sheet material, as shown in FIG. 3B, by a bandpass filter designed with a pass band of 2 kHz to 10 kHz. A frequency component in a specific region is extracted from the frequency components. After that, the sheet material information detection unit 102 acquires (detects) information about the sheet material by reading, for example, a peak voltage value based on the output signal from the bandpass filter.

The figure which shows the structure of the sheet material information detection apparatus and sheet material processing apparatus which concern on embodiment of this invention. The figure explaining the sheet material information detection operation | movement in the said sheet material information detection apparatus. The figure explaining the handling of the signal in the said sheet material information detection apparatus. The figure which shows the example which used the limiting member in the said sheet material information detection apparatus.

Explanation of symbols

2 External force application unit 3 Signal detection unit 5 Sheet material information detection unit 20 External force application member 101 Filter 102 Sheet material information detection unit 301 Restriction member B Paper type detection device (sheet material information detection device)
C Sheet material processing part P Sheet material

Claims (10)

In the sheet material information detection apparatus for detecting information on the sheet material,
An external force applying means for applying an external force to the sheet material;
Signal detection means for detecting a signal from the sheet material due to the external force;
A filter that removes or extracts a frequency component of a specific region included in the output signal from the signal detection means;
With
A sheet material information detection apparatus for detecting information on a sheet material based on a signal obtained by applying the filter.   The sheet material information detection apparatus according to claim 1, further comprising sheet material information detection means for detecting information on the sheet material based on an output signal from the filter.   The sheet material information detecting means detects information on the sheet material by comparing an output signal from the filter with data relating to a relationship between a previously obtained output signal and sheet material information. The sheet material information detection apparatus according to claim 2.   The sheet material information detection apparatus according to claim 1, wherein the external force application unit applies a physical force.   The sheet material information detection apparatus according to claim 1, wherein the external force is a plurality of impacts with different collision speeds.   The sheet material information detection apparatus according to claim 1, wherein the external force is vibration having different frequency components.   The sheet material information detection apparatus according to claim 1, wherein the signal detection unit includes a piezoelectric element.   The sheet material information detection apparatus according to claim 1, wherein the filter is a band-pass filter.   9. The sheet material information detection apparatus according to claim 1, wherein the information on the sheet material is a type of the sheet material. The sheet material information detection apparatus according to any one of claims 1 to 9, and a process corresponding to the detection result selected from a plurality of processes based on a detection result of the sheet material information detection apparatus, A sheet material processing apparatus comprising: a sheet material processing unit that executes sheet processing.

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