JP2006306578A - Device and method for outputting signal on sheet, and image forming device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To control a situation that a bottom part of a recessed external force receiving unit is brought into contact with a sheet before the sheet is brought into contact with an external force providing unit. <P>SOLUTION: The device for outputting signal on a sheet comprises an external force providing unit to provide the external force to the sheet, a recessed external force receiving unit to receive the external force provided on the sheet by the external force providing unit via the sheet, a signal output unit to output the signal corresponding to the physical properties of the sheet according to the force received by the external force receiving unit via the sheet, and a separation means to separate the sheet from a bottom part so that the sheet is curved toward the external force providing unit from the recessed bottom side of the external force receiving unit. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a signal output device and output method relating to a sheet material. The present invention also relates to an image forming apparatus such as a copying machine and a printer, and a sheet material conveying apparatus.

  An image forming apparatus such as a copying machine or a printer has a sheet material conveying process and an image forming process, and is required to be performed under conditions (such as a conveying condition and an image forming condition) suitable for the sheet material to be used.

  Therefore, acquisition of information regarding the sheet material is important when setting these conditions.

  Japanese Patent Application Laid-Open No. 2004-133867 describes a technique for acquiring information related to a sheet material.

  In the same document, as shown in FIG. 16, in a state where the sheet material P is interposed between the impact applying unit 2500 for applying an impact and the detection unit 2510, the impact applying unit applies an impact to the sheet material. Add. The impact is transmitted to the detection unit 2510 via the sheet material P, and is output as a piezoelectric signal from a piezoelectric element provided in the detection unit. The type of paper is determined using the fact that this output signal changes according to the physical properties of the sheet material.

Further, this document describes that a signal reflecting the bending of the sheet material can be acquired by providing a recess on the side that receives an impact via the sheet material.
JP 2004-26486 A

  However, it has been found that even when a concave member is provided on the side that receives an impact via the sheet material, the sheet material and the bottom of the concave member may be unintentionally contacted before applying an external force.

  As shown in FIG. 17, this is caused by the undulation of the sheet material itself.

  Thus, when contact of both unintentional arises, even if it is going to acquire the information regarding the bending of a sheet material, since the said bottom part 2620 and the sheet material P are contacting before giving external force, it is related with the bending of a sheet material. It becomes difficult to obtain information.

  Therefore, the present invention provides a signal output device, a signal output method, and the like provided with means for suppressing unintentional contact between a sheet material and the bottom.

The signal output device according to the present invention, an external force applying unit for applying an external force to the sheet material,
According to the concave external force receiving portion that receives the external force applied to the sheet material by the external force applying portion via the sheet material, and the force received by the external force receiving portion via the sheet material, A signal output unit that outputs a signal corresponding to a physical property and the sheet material are separated from the bottom so that the sheet material is curved from the concave bottom side of the external force receiving unit toward the external force applying unit. And a separating means for making it happen.

The signal output device relating to the flexible sheet material according to the present invention is:
An external force applying part for applying an external force from one surface of the sheet material to the other surface;
A concave external force receiving portion that receives the external force applied to the sheet material by the external force applying portion via the sheet material;
A signal output unit that outputs a signal corresponding to the physical properties of the sheet material in accordance with the force received by the external force receiving unit via the sheet material;
In order to separate the other surface of the sheet material from the concave bottom portion of the external force receiving portion before the external force applying portion contacts with one surface of the sheet material, a direction opposite to the external force applying direction is provided. Separating means for applying a force to the sheet material.

  In addition, the image forming apparatus according to the present invention is based on the conditions determined by the image forming condition setting unit for setting the image forming condition and the image forming condition setting unit based on the signal output from the signal output device. And an image forming unit for performing image formation.

  Further, the conveying device according to the present invention is based on a condition determined by the conveying condition setting unit for setting the conveying condition of the sheet material based on the signal output from the signal output device and the condition set by the conveying condition setting unit. And a transport unit for transporting the sheet material.

Furthermore, the signal output method according to the present invention is a method for outputting a signal corresponding to the physical properties of a flexible sheet material,
Applying an external force from one surface of the sheet material to the other surface;
Receiving the external force on the other surface of the sheet material bent by the application of the external force;
A step of outputting a signal corresponding to the physical properties of the sheet material according to the received external force,
Before the step of applying the external force, a force from the other surface to the one surface is applied to the sheet material.

  According to this invention, it can suppress that a sheet | seat material and the bottom part of an external force receiving part contact before external force provision.

  Hereinafter, modes for carrying out the present invention will be described.

(1) Signal Output Device Concerning Sheet Material As shown in FIG. 1, the signal output device according to the present invention includes an external force applying unit 1000 for applying an external force from one surface of the sheet material P toward the other surface. In accordance with the external force receiving portion 1010 that receives external force applied to the sheet material P by the external force applying portion 1000 via the sheet material P, and the force received by the external force receiving portion via the sheet material P, A signal output unit 1030 that outputs a signal corresponding to the physical properties of the sheet material, and a spacing that separates the other surface of the sheet material from the bottom before the external force applying unit 1000 contacts one surface of the sheet material Means 1040 are provided.

  Reference numeral 1020 denotes the bottom of the concave structure. Such a separating means applies a force in a direction opposite to the external force applying direction to the sheet material in order to separate the other surface of the sheet material from the concave bottom portion of the external force receiving portion. Become.

  Since the separating means 1040 is configured to press the sheet material P outside the external force receiving portion 1010 in the external force applying direction so as to be lowered in the external force applying direction from the convex portion 1025 of the external force receiving portion 1010. P curves on the bottom portion 1020 of the external force receiving portion in a direction away from the bottom portion 1020. Thereby, before applying external force to a sheet | seat material, it can suppress that the previous term bottom part 1020 and the sheet | seat material P contact unintentionally.

  In the present invention, the separation means refers to separating the sheet material from the bottom so that the sheet material P is curved from the concave bottom 1020 side of the external force receiving portion toward the external force applying portion. It is the separation means for.

  In addition, although two places are described as the separation means on the left and right sides of the paper, one place may be used as long as the contact can be reduced.

  The waviness of the sheet material depends on the environment (humidity condition and heating condition) in which the sheet material is placed, but the height difference is about 0.1 mm to 1 cm with a period of several millimeters to several centimeters. Therefore, although it depends on the area of the low part of the external force receiving part, the separation means is particularly important when the level difference between the bottom part and the convex part is included in the range of the height difference.

  For example, when the separation means is provided on the outer periphery of the external force receiving portion as shown in FIG. 1, the height difference between the convex portion of the external force receiving portion and the lower portion of the separation means can be in the range of 0.1 mm to 1 cm. .

  Although FIG. 1 is shown as an example of the separation means, for example, as shown in FIG. 2, at least a part of the periphery of the bottom portion 1220 of the external force receiving portion 1210 is provided with a taper shape that falls outward from the bottom side on the convex portion 1225. Separating means 1240 may be provided so that the sheet material P is curved on the external force receiving portion 1220 in a direction away from the bottom portion 1020. In the figure, reference numeral 1230 denotes a signal output unit.

  As described above, in the present invention, the case where the separating means is provided separately from the external force receiving portion has been described. However, the external force receiving portion 1810 may protrude from the base 1880 as shown in FIG. In this case, the structure itself that projects the external force receiving portion from the pedestal is the separating means, and no further separating means 1840 may be provided around the external force receiving portion. The upper surface of the concave external force receiving portion, that is, the convex portion needs to protrude at least from the pedestal surface.

  Further, the sheet material does not necessarily have to be curved as described above as long as the sheet material is separated from the bottom portion of the external force receiving portion on the bottom of the external force receiving portion.

  As another separation means, for example, a hole capable of blowing a gas such as air in a direction opposite to the direction in which the external force is applied is provided in the bottom of the external force receiving portion, and the sheet material and the bottom of the external force receiving portion are provided by this blowing force. Can be separated from each other.

  As another means, the sheet material and the external force receiving portion bottom can be separated by sucking the sheet material in the direction opposite to the direction in which the external force is applied. Instead of suction, the sheet material may be separated using electrostatic attraction. In addition, since the cause of contact between the bottom portion of the external force receiving portion and the sheet material before applying the external force may be the influence of static electricity, for example, it is also preferable to neutralize the sheet material or the external force receiving portion before applying the external force. .

  Further, the separating means 1040 as shown in FIG. 1 is not necessarily fixed. If the sheet material is separated from the bottom of the external force receiving portion by the separating means 1040 before the external force applying portion contacts the sheet material. Good. For example, before the external force is applied, a configuration is possible in which the separation means first moves to a desired position in the external force application direction, and then the external force application portion starts moving toward the sheet material to apply the external force.

  In the present invention, by using an external force receiving portion having a concave portion having a predetermined size, and limiting the amount of deformation behavior of the sheet material that is deformed by applying an external force within a predetermined range, the mechanical properties of the sheet material (bending, compression) ) Can be detected with high accuracy.

  The concave structure of the external force receiving portion in the present invention means a step which can be bent toward the concave bottom when the sheet material is given an external force.

(Sheet material)
The flexible sheet material used in the present invention is a recording medium used in the image forming apparatus, such as plain paper, glossy paper, coated paper, recycled paper, OHP (transparent plastic sheet), and the like. Of course, the sheet material includes a banknote, a document on which a document is previously written, and a sheet on which an image is formed only on one side. The term “flexible” refers to bending when a force is applied to an external force receiving portion having a recess via a sheet material. One surface and the other surface of the sheet material are, for example, a front surface and a back surface of paper.

(External force application part)
The external force applying unit used in the present invention uses a material that applies an external force to the sheet material and the external force receiving unit by colliding a member having a predetermined mass at a predetermined speed. For example, a member such as a metal bar is accelerated and applied by a spring. The mass of the member can be appropriately set, but is preferably about 1/10 to 10 times the weight of the area to be measured of the sheet material. As an example, when letter-size (about 215.9 × 279.4 mm) paper having a basis weight of about 100 g / m ² is used as a sheet material, a range of 0.5 g to 50 g is preferable.

  The collision speed is set to a value sufficient to deform the sheet material. Here, the deformation includes bending and compression. In the case of the same paper as described above, although it depends on the mass of the member and the presence or absence of acceleration such as gravity, 0.05 m / sec. To 5 m / sec. The range of is preferable.

  Of course, when the sheet material is thinner, both the mass and the collision speed of the application member can be set to smaller values, and when the sheet material is thicker, the values are set to larger values. In any case, it is determined within a range in which the sheet material does not break, and more preferably in a range in which the sheet material does not dent or bend.

  The external force applying unit may apply an external force to the sheet material based on contacting a solid member with the sheet material, or may be configured to spray a fluid such as air. The drive source of the external force imparting member is one that drives the member by mechanical or electromagnetic energy, for example, mechanical means such as gravity or a spring, electromagnetic means such as a motor, solenoid or voice coil, Conversion mechanisms such as cams, shafts, and gears may be combined and used as appropriate. As an example, there is a configuration in which a hammer supported by a rotary bearing is accelerated by a motor and a cam.

  As an external force, a signal may be output when a member is caused to collide with a sheet material to apply an impact, or an object vibrating at a predetermined cycle is brought into contact with the sheet material from a non-contact state.

(Applying external force)
As a preferable aspect in the present invention, it is possible to apply an external force multiple times to one sheet material by the external force applying unit.

  This can be realized by a mechanism that causes a plurality of collisions, for example, by releasing energy stored in a spring a plurality of times with a multistage cam or the like. At the time of each collision, the value of external force (for example, speed) may be the same. When the values of the external forces are the same, for example, statistical processing such as taking an average of outputs at that time can be performed to increase the accuracy of information. Moreover, you may perform the collision which changed the value of external force. When the value of the external force is varied, since the reaction of the sheet material is different, more multifaceted information can be obtained.

  Specifically, after applying an external force to the sheet material with the first force, a second force weaker than the first external force is applied to the sheet material. Of course, the order may be reversed, but when the external force is applied with a force different in magnitude as described above, when the first force is applied, a signal that strongly reflects the physical properties relating to the compressive strength of the sheet material can be obtained, When an external force is applied with a second force that is weaker than the first force, a signal that strongly reflects the physical properties relating to the bending strength of the sheet material can be acquired.

  Thus, in the present invention, only one type of external force may be used or a plurality of types of external force may be used. Moreover, the signal output according to the physical property of a sheet | seat material may be performed only by external force application once, and external force application may be performed in multiple times. When external force is applied multiple times (that is, when one type of external force is applied multiple times or when multiple types of external force are applied at different timings), multiple data can be obtained, so identification accuracy is also high. Get higher. When the external force is applied a plurality of times in this way, 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.

  In addition, as a method of applying external force, a method of causing the external force applying member to collide with the sheet material from a distant position, or a method of applying an impact force from the applying member to the sheet material while keeping the applying member in contact with the sheet material Can be mentioned. That is, in the signal output process, the external force imparting portion, the sheet material, and the impact receiving portion must be in contact with each other at the same time, but the positional relationship may be arbitrarily set at other times.

  The application of the external force as described above is performed when the sheet material is stationary (for example, stocked in a stocker), the sheet material is conveyed, or the conveyed sheet material P is temporarily stopped. It can be carried out.

  When an external force is applied to the sheet material P that is being conveyed, the surfaces of the external force applying member and the sheet material rub against each other, so that the surface state of the sheet material can be easily detected. When an external force is applied to the sheet material in a stopped state, the external force detection means can reduce noise components accompanying the movement of the sheet material. Such a conveyance state is appropriately designed and controlled according to necessary information.

(External force receiving part)
The concave external force receiving portion having a bottom portion according to the present invention will be described in detail.

  The external force receiving portion is sufficiently durable against the applied external force and is made of a material that can propagate the external force to a pressure sensitive element as a signal output portion. Preferred are metals, resin materials, and the like.

  The concave external force receiving portion having a bottom portion has a shape capable of bending the sheet material toward the bottom portion side by applying an external force. By applying an external force, the sheet material is bent on the bottom portion, and the surface of the sheet material is pressed against the bottom portion.

  The concave shape of the external force receiving portion may be a rectangular shape, a saw shape, or a curved shape, which is appropriately selected according to the application.

  4 to 7 show examples of the external force receiving portion.

  In the example of FIG. 4, a rectangular hole-shaped concave structure having widths W <b> 1 and W <b> 2 and a depth d is provided on a plate-like member as an external force receiving portion. 1425 indicates a convex portion, and 1420 indicates a bottom portion.

  In the example of FIG. 5, a groove-like concave structure having a width W1, a length W2, and a depth d is provided on a plate-like member, and an inclined structure 1511, that is, a tapered shape is provided on the edge of the side wall portion of the step. . In the inclined structure 1511, the edge of the side wall portion of the step structure 4 is worn by friction with the sheet material or the like, and the shape changes, and the relationship between the width W1, the length W2, and the depth d changes. This is provided for the purpose of substantially suppressing the variation in the dimensional relationship of the structure. Specific designs are described in detail in the examples. The inclined structure 1511 preferably has a gradient of 5% to 20%.

  In the example of FIG. 6, a relief structure 1612 is further provided in the example of FIG. The example of FIG. 6 is used particularly when detecting information on the sheet material being conveyed. The relief structure 1612 is a surface of the receiving member 3 that faces the traveling direction of the sheet material (the front end of the sheet material is directed). It is provided to release excessive force due to the collision between the front end of the sheet material and the receiving member. In the example shown in FIG. 6, even a sheet material conveyed at high speed has an effect of preventing element damage and enabling stable information detection. In addition, as shown in FIG. 7, the structure which has the convex part 1725 only in the one side of the bottom part 1720 of the external force receiving part 1703 is also possible.

(Signal output section)
The signal output unit is composed of, for example, a pressure sensitive element.

  A pressure-sensitive element is an element that converts a mechanical action such as pressure or vibration into an electric signal or an optical signal.

As an example of an element (electromechanical conversion) that converts a mechanical action into an electric signal, an element such as a semiconductor diaphragm type, a capacitance type, an elastic diaphragm type, or a piezoelectric type is used. Preferable examples include inorganic or organic materials having piezoelectric characteristics, such as PZT (lead zirconate titanate), PLZT, BaTiO ₃ , PMN-PT (Pb (Mg1 / 3Nb2 / 3) O ₃ —PbTiO _3. ) Or an organic piezoelectric material. When a piezoelectric element is used, the external force is detected as a voltage signal. Here, the signal output section includes the case where the element itself is directly exposed or covered.

  As an element that converts a mechanical action into an optical signal, an element that utilizes reflection of light from a member, transmission from a member, or change in polarization due to mechanical movement of the member is used. For example, a method of reading the movement of a member by applying a laser beam to the member and reading the direction change of the reflected light from the member with a light receiving element (such as a split photodiode), or applying a two-beam laser beam to the member to interfere with it. A method of reading the motion speed of the member from the so-called “laser Doppler velocimeter” is also suitable.

  In addition, although the case where the signal output unit is provided on the external force receiving unit side is illustrated in the drawing, it can also be provided on the external force applying unit side. For example, a leaf spring that can be bent by an impact is provided on the external force receiving portion, and the displacement of the spring may be detected by a piezoelectric element or the like.

  A piezoelectric ceramic plate is used as a pressure-sensitive element that functions as a signal output unit, a member having sufficiently higher rigidity than the pressure-sensitive element is used for the impact receiving part and the fixing material, and the pressure-sensitive element is externally applied by the external force applying part. The deformation mode is mainly compressed in the thickness direction.

  As another preferred example of using piezoelectric ceramics as the pressure-sensitive element, an elastic body having elasticity that causes the pressure-sensitive element to bend and deform is used for the external force receiving portion, and the fixing material is elastically deformed such as rubber. A deformation mode in which the pressure-sensitive element 5 mainly expands and contracts as the receiving part bends and deforms due to an external force applied by the external force applying part, such as using a material or fixing only one end of the pressure-sensitive element with a fixing material. It is set as the structure which takes. Wiring is drawn from the pressure sensitive element. The wiring 6 is made of a highly flexible material so as not to give unnecessary constraints to the pressure sensitive element 5. Furthermore, these are fixed to the base 8 as appropriate. The pedestal 8 is preferably a material having high rigidity and high temperature stability, and the material is appropriately selected from metal and resin. It is also preferable to lay a vibration isolating material in order to brake the vibration appropriately. The installation position of the vibration isolator may be anywhere as long as unnecessary vibration can be braked.

  The fixing material 1870 used in the present invention will be described in detail with reference to FIG.

  By appropriately selecting the fixing material 1870, information on the sheet material can be detected with higher efficiency. An example in which a piezoelectric ceramic thin plate is used as the pressure-sensitive element 1850 will be described. For example, when an elastic body or a viscoelastic body (rubber or the like) that causes deformation by a force applied to the sheet material is used as the fixing material 1870, the pressure-sensitive element 1850 and the receiving member 1810 substantially operate as a unimorph element and mainly. Since a relatively high voltage can be obtained by bending deformation, there is an effect of improving the S / N of signal processing.

  For example, when a rigid body is used as the fixing member 1870, the pressure-sensitive element 1850 mainly undergoes compressive deformation. In this case, the pressure-sensitive element is compressed as a whole with respect to the applied force. Since the difference in generated voltage depending on the place where it is applied is small, there is an effect that individual differences in output vibration due to, for example, tolerances in device assembly can be suppressed. Further, if the fixing material 1870 is selected such that the properties such as hardness, viscoelasticity, and resistivity change appropriately due to changes in the environment such as temperature and humidity, the output can be changed according to the environment. Output fluctuations due to environmental changes can also be corrected. In addition, the fixing member 1870 is preferably designed in a shape that does not cause unnecessary resonance due to external force application or external vibration, and further, it is preferable that vibration is blocked from the outside by a damper such as rubber. Further, since the fixing material 7 faces repulsion due to the application of external force, it is preferable that the fixing material 7 has an inertial mass of a certain degree or more, at least a mass larger than that of the external force application member, and more than 5 times the mass of the external force application member. It is more preferable to have. In the figure, 1840 is a separating means, 1890 is a sheet material supporting means, 1880 is a substrate, 1825 is a convex portion in an external force receiving portion, 1820 is a bottom portion, and 1860 is a wiring.

  In FIG. 8, when the sheet material is transported from the front side to the back side, the separating means 1840, the supporting means 1890, and the external force receiving portion 1810 are provided with a taper shape that is lowered toward the board 1880 side toward the front side of the paper. It is good to leave.

(Physical properties of sheet material)
The “physical properties of the sheet material” are the bending rigidity of the sheet material, that is, the physical properties relating to the ease of bending and the difficulty of bending, and the rigidity (compressive strength) in the thickness direction. The signal output device according to the present invention outputs a signal corresponding to at least the bending rigidity.

(2) Signal Output Method for Sheet Material A signal output method according to the present invention will be described.

  Specifically, applying an external force from one surface of the sheet material to the other surface, receiving the external force on the other surface of the sheet material bent by the application of the external force, and receiving Outputting a signal corresponding to the physical properties of the sheet material according to the external force, and before the step of applying the external force, the force from the other surface to the one surface with respect to the sheet material Is granted. By doing in this way, before a sheet material and an external force provision part contact, it can reduce that the bottom part of the external force receiving part which has the said concave structure, and a sheet material contact.

  The force directed toward the one surface is generated by, for example, the above-described separating means. For example, an external force is applied to the sheet material by the external force applying unit 1000 in a state where the sheet material P is curved in a direction away from the bottom portion 1020 on the bottom portion 1020 of the external force receiving portion 1010 shown in FIG. In this manner, by applying an external force to the sheet material in a state where the sheet material is curved, it is possible to suppress the contact between the sheet material and the bottom portion before the external force applying portion and the sheet material are in contact with each other. it can. More specifically, as shown in FIG. 13A, an external force is applied to the sheet material in a state where the sheet material P is curved so as to be separated from the bottom portion 2320. The external force application unit 2300 contacts the sheet material on the bottom 2320. The sheet material bends in the external force application direction (FIG. 13B). Finally, the sheet material is sandwiched between the external force applying part and the external force receiving part and compressed (FIG. 13C).

(3) Image Forming Device, Conveying Device A process when the signal output device according to the present invention is used in the image forming device will be described with reference to FIGS.

  As shown in FIG. 10, using the signal output device described above, an external force is applied to the sheet material (step S1), and a signal is obtained from the signal output device (step S2). Image forming conditions are set using the output signal (step S3). Then, image formation is performed under the set conditions (step S4).

  In setting the conditions, the conditions can be determined by comparing the output signal and the table in which the setting conditions for the output signal are stored in advance with the actually output signal.

  Here, the image forming conditions include, for example, the ink discharge amount, the interval between the conveying rollers when the sheet material is conveyed, and the temperature condition when the image is formed on the sheet material (for example, fixing toner as in electrophotography). For example, a temperature condition when performing fixing, a pressing condition when fixing, and the like. In addition, it relates to sheet material conveyance conditions (conveyance speed, pressure between conveyance rollers, interval between rollers), discharge conditions to sort discharge (sorter), drying conditions for sheet material after image formation, and stapling. There are conditions.

  Although the case where the signal output apparatus according to the present invention is used in an image forming apparatus has been described, the present invention can also be applied to a sheet material conveying apparatus without an image forming process. In that case, the pressure between the rollers used when the sheet is conveyed is adjusted based on information from the signal output device.

  Of course, the user may directly control the image forming conditions on the sheet material, the conveying conditions of the sheet material, and the like based on the voltage signal output from the signal output device.

  Next, with reference to FIGS. 11 and 12, a case will be described in which a step of determining what type of sheet material is used, for example, the type of paper or the like.

  For example, in the image forming apparatus, it is first determined whether or not to determine the sheet material (S0). This step can be omitted.

  Next, an external force is applied to the sheet material (S1). Thereby, information is output from the information output device (S2). Then, as shown in FIG. 12, the determination unit determines whether or not the sheet material can be determined based on the information stored in the storage unit in advance (S3). Setting is performed (S4), and image formation is performed (S5). If it cannot be determined in step S3, it is possible to go through the step of applying an external force again.

  The signal output apparatus according to the present invention is not limited to the above-described image forming apparatus (copying machine, printer, facsimile), and of course a conveyance device having a conveyance unit for conveying a sheet material, that is, a sheet material conveyance mechanism. In addition, the present invention can be applied to, for example, a sheet material number measuring machine, a sheet material type sorting machine, and an automatic cash deposit / withdrawal machine having a bill conveyance mechanism.

(Signal processing)
A processing circuit for processing a signal from the sheet material signal output device of the present invention will be described.

  FIG. 14 shows an example of a voltage waveform generated from the sheet material information detection apparatus. FIG. 14A shows an output waveform when the sheet material is not interposed between the external force applying portion and the external force receiving portion.

  FIG. 14B shows an output waveform when a sheet material is sandwiched.

  In both figures, area A is the time zone before the tip of the external force application member collides with the bottom of the external force receiving portion inside the concave shape (in the case of FIG. 14B, the sheet material is bent and deformed). is doing.).

Region B shows a time region after colliding with the bottom of the external force receiving portion (in the case of FIG. 14B, the sheet material is sandwiched). Here, as an example, data using paper (Xerox, PREMIUM MULTIPURPOSE 4024 PAPER 75 g / m ² ) is used as the sheet material.

  As shown in FIG. 14A, in the case of no sheet material, no voltage is generated in the region A, and the voltage is generated in the region B. In contrast, as shown in FIG. 14B, when the sheet material is sandwiched, an output in which the generated voltage gradually increases in the region A is obtained. This is due to the generation of voltage due to the sheet material being gradually deformed and the pressure applied to the pressure-sensitive element functioning as a signal output unit gradually increasing accordingly.

  Further, in the region B of FIG. 14B, a peak-like generated voltage is generated and immediately decays. This corresponds to the behavior in which the application member collides with the receiving material with the sheet material interposed therebetween and further recoils away.

  The signal detected in the present invention is an electric signal (for example, a voltage signal) generated from the pressure-sensitive element when the sheet material directly contacts the receiving member.

  In the present invention, the waveform of the region A and the region B is processed by the processing circuit from the waveforms shown in FIG. 14 to extract and output the feature amount. Information that is preferably extracted by the processing circuit includes, for example, a gradual increase rate, rise, maximum generated voltage value (peak voltage), amplitude and frequency component, peak width, differential value, integral value, attenuation, and the like. Of course, only the feature amount of the region A may be extracted, or only the feature amount of the region B may be extracted, and it goes without saying that only one of the feature amounts may be used as information.

  Further, the waveform in the case of no sheet material in FIG. 14A is used as information for detecting the state of the sheet material information detection apparatus. Specifically, sheet material information detection devices are subject to individual differences, wear and other causes, deterioration due to environmental (especially temperature, humidity), disturbances such as vibration and electrical noise, sheet material information output devices and sheet materials described later. It is detected that the state of the output signal of the sheet material information detection device fluctuates due to an error during incorporation into the processing device.

  Thus, the signal which detected the state of the sheet material information detection apparatus is used as reference information when detecting information on the sheet material. The reference information is used as follows. By taking the reference information and information when the sheet material is sandwiched, for example, the ratio, difference, deviation or the like of both data values, correction can be performed and detection accuracy can be improved. Also, if such reference information exceeds a certain range, or if the variation in values when this reference information is acquired multiple times exceeds a certain range, it is determined that the device is abnormal and an alarm is issued. You can also Furthermore, the operation of the sheet material information detection device itself may be controlled (for example, changing the strength of an applied external force or giving a bias to the output) so that such reference information falls within a certain range. Is possible.

  In the sheet material signal output device according to the present invention, the above-described feature amount is compared with a table in which a sheet material signal is recorded in advance, and the sheet material type, model number, state change, printing state, double feed, and the like are determined. You may make it output. When the signal of the sheet material varies 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 tables. In the sheet material information output device of the present invention, the value of the feature value itself may be used as determination information, or a value obtained by performing predetermined conversion on the feature value may be used as determination information. In addition, when the signal of the sheet material differs depending on the environmental condition, the conveyance state, etc., processing for correcting the value may be performed.

  In the sheet material signal output device of the present invention, the feature amount or the result determined from the feature amount can be converted into a control value corresponding to the sheet material information by a predetermined calculation formula and output. That is, for example, an electrophotographic apparatus which is an example of an image forming apparatus can output a parameter value for controlling the power for heating the fixing device according to the maximum voltage generated by the pressure sensitive element.

  Furthermore, another means (for example, an input of an artificially set paper model number or a signal from a separately provided sensor) may be determined together with the sheet material.

  In addition, in order to acquire information on the sheet material, it is not always necessary to make a determination in the processing circuit, and a person may make a determination based on a signal output from the signal output unit.

Example 1
In the present embodiment, a sheet material information detection apparatus having the structure shown in FIG. 8 was produced, and a sheet material information output apparatus was configured and mounted on an electrophotographic apparatus (sheet material processing apparatus). 8 is a cross-sectional view and FIG. 9 is a perspective view.

  The apparatus was configured as follows.

  First, the signal output unit 1850, the external force receiving unit 1810, and the fixing material 1870 were as follows. What is necessary is just to provide a fixing material as needed.

  The external force receiving portion 1810 is made of a stainless steel (SUS316) plate having a width of 15 mm, a length of 10 mm, and a thickness of 1.5 mm. As the step structure 4, the width W1 is 10 mm, the length W2 is 10 mm, and the depth d is 0. What provided the groove-shaped concave structure of 3 mm was used. In the figure, 1825 is a convex portion, 1820 is a bottom portion, 1850 is a pressure-sensitive element, and 1860 is a wiring.

  Further, an inclined structure (1611 in FIG. 6) having a 10% gradient and a width of 0.5 mm was provided at the edge of the side wall portion around the bottom of the external force receiving portion. Further, a relief structure (1612 in FIG. 6) having a gentle inclined structure is provided at one end of the receiving member.

  As the pressure sensitive element, a piezoelectric element having a structure in which PZT (lead zirconate titanate), which is sandwiched between silver electrodes, is used. The size of the piezoelectric element is 5 mm in length, 3 mm in width, and 0.3 mm in thickness. did.

  As the fixing material, a stainless steel (SUS316) plate material having a width of 15 mm, a length of 10 mm, and a thickness of 1.5 mm was used.

  The receiving member 1810, the pressure-sensitive element 1850, and the fixing material 1870 are bonded to each other with an adhesive mainly composed of an epoxy resin, and the fixing material 7 is bonded to a base 1880 as a substrate. The pedestal 1880 was made by embedding a metal weight (not shown) in a highly heat-resistant resin having high hardness stability near room temperature. The metal weight is effective for imparting sufficient inertial mass to the element portion including the pedestal with respect to the applied external force and stabilizing the output signal.

  The pedestal 1880 is provided with a first paper guide (sheet material supporting means) 1890. Further, a second paper guide 1840 is provided as a separating means according to the present invention so as to face the first paper guide 1890.

  Since the sheet material P is sandwiched between the first paper guide 1890 and the second paper guide 1840, the sheet material was curved in a direction away from the bottom portion on the bottom of the external force receiving portion 1820. Therefore, on the bottom portion, the external force application unit (described later) and the sheet material did not come into contact before applying the external force.

  The pedestal 1880 is fixed to a sheet material processing apparatus, which will be described later, via a damper (O-ring-shaped rubber material) (not shown).

  On the other hand, an external force applying means 1800 for applying an external force to the sheet material P is disposed at a position facing the external force receiving portion. The external force applying means 1800 was made of a stainless steel (SUS316), a hammer having a spherical surface with a mass of 4 g and a tip shape of a radius of 50 mm.

  It should be noted that the output signal from the pressure-sensitive element when an external force is applied to the sheet material in FIG. 3 and the external force in the state where the sheet material is previously in contact with the bottom of the external force receiving portion without providing a separation means as in this embodiment. A comparison with the output signal in the case of giving is shown. FIG. 3A shows data in the case where contact is made in advance without providing the separation means, and FIG. 3B shows data in the case where the separation means is provided. The paper is a sheet having a basis weight of 163 g / m 2 and a thickness of 204 μm. As is apparent from FIG. 3, it can be seen that there is a large difference in the output signal between the case where there is an unintended contact and the case where there is no unintentional contact before the external force is applied, even though they are the same sheet material. As compared with the case where there is an unintended contact as described above, a more accurate output signal can be obtained by using the present invention. In addition, since the sheet material and the bottom of the external force receiving portion are not in contact with each other when the external force is applied, the sheet material is always bent by the application of the external force, so that a signal reflecting the deflection is output together with the physical properties related to compression. Become.

(Example 2)
In the same manner as in the first embodiment, an example will be described in which an external force is applied twice to determine the type of sheet material.

  8 is held at a position about 2 mm away from the sheet material P except when an external force is applied, but is accelerated by a drive source when an external force is applied and gives an impact force as an external force. In this embodiment, the drive source is configured to accelerate a hammer supported by a rotary bearing with a motor and a cam. In the present embodiment, two types of external forces are applied to one sheet material information detection. In the first external force application, the external force applying portion was accelerated to 0.5 m / second and collided. After applying the first external force, the external force applying unit 1800 is once separated from the sheet material P, and then the second external force is applied. In the second external force application, the external force applying portion was accelerated to 0.2 m / sec and collided with the sheet material P. After applying the second external force, the external force applying means 1 is supported at a position away from the sheet material P. The first external force application and the second external force application are performed in a state where the sheet material P is transported in the direction corresponding to the back direction from the front side of the drawing at approximately 0.2 m / sec. The interval was set to 0.1 seconds.

  Next, the operation of this embodiment will be described.

  First, an external force was applied to the external force receiving portion without the sheet material P. As the external force application, the first external force application and the second external force application were performed under the above conditions. The output voltage from the pressure-sensitive element 1850 at that time (hereinafter referred to as “signal when no sheet is present”) is stored in a storage unit provided to the processing circuit.

  This signal when there is no sheet is used as a reference signal to be compared with an output when a sheet material described later is narrowed. In this example, a voltage waveform having a peak value of 11.0 V was obtained (see FIG. 14A). Further, the signal when there is no sheet material is also used for detecting the state of the signal output device itself relating to the sheet material. For example, if the signal value when there is no sheet material exceeds a predetermined range, it is determined that the sheet material information detection device is abnormal and a failure display, adjustment or replacement command is issued, or the sheet material information detection device is A procedure for switching the operation of the sheet material processing apparatus to a mode not in use is performed.

  In addition, when using paper as the sheet material P, dust generated from the paper (hereinafter referred to as paper dust) adheres, or as a sheet material processing apparatus, powder toner such as a laser beam printer or a copying machine is used. In the case of an apparatus to be used, scattered toner may adhere, but by applying an external force in the absence of the sheet material P, by applying appropriate vibration, the above paper dust and toner are removed to perform cleaning. You can also.

  Next, in the state where the sheet material P was sandwiched, the external force application was performed under the above conditions under the first external force application and the second external force application.

Hereinafter, an output waveform (see FIG. 14B) when an external force is applied to the sheet material will be described. In the drawing, as an example, external force application is the first external force application condition, and paper is an example of copier paper (Xerox, PREMIUM MULTIPURPOSE 4024 PAPER 75 g / m ² ). In the region A, the tip of the application member is inside the stepped structure of the receiving portion, but before the time when it collides with the bottom of the stepped structure (in the case of FIG. 14B, the sheet material is bent and deformed), Region B is a time region after colliding with the bottom of the step structure (in the case of FIG. 14B, the sheet material is sandwiched).

  In region A in FIG. 14B, an output in which the generated voltage gradually increases is obtained. This is due to the fact that the sheet material is gradually bent and deformed, and the pressure applied to the pressure-sensitive element is also increased accordingly. In this embodiment, the processing circuit detects that the generated voltage near the end of the region A is 0.32 V as the feature amount of the region A. In this step, the external force imparting portion decelerates due to resistance due to bending of the sheet material.

  In the subsequent region B of FIG. 14B, a peak-like generated voltage is generated and immediately attenuates. This corresponds to the behavior in which the application member collides with the receiving material with the sheet material interposed therebetween and further recoils away. At this time, the sheet material is deformed in the direction of being crushed in the thickness direction, and an output reflecting the mechanical characteristics of compression is obtained. In this embodiment, the processing circuit detects that the generated voltage at the peak of the region B is 3.50 V as the feature amount of the region B.

  Further, similarly, the output waveform at the time of applying the second external force was processed. In the second external force application, the generated voltage near the end, which is the feature amount of the region A, was 0.20 V, and the generated voltage at the peak, which is the feature amount of the region B, was 1.20 V.

An example in which three brands are identified as a sheet material by the apparatus of the present embodiment will be described. As a sheet material, sheet material A (Xerox, PREMIUM MULTIPURPOS 4024 PAPER 75g / m ² ), sheet material B (FOX RIVER PAPER, FOX RIVER BOND 75g / m ² ), sheet material C (Sumitomo 3M, CG3300) . As an example, only the generated voltage value at the peak in the region B is used as the feature amount, and the first external force application condition and the second external force application condition are used as the external force application conditions. In this identification experiment, a filter that eliminates unnecessary frequency band vibration from the waveform is used so that signal processing in the latter stage can be easily performed in practice. Is slightly different from the values used in the description of the waveform. The following determination is performed as a relative value by dividing by all the signal values when there is no sheet.

  Although the sheet material can be identified only by the first or second external force applied peak voltage value, it is possible to identify with higher accuracy by using both.

  As described above, since the sheet material A and the sheet material B are paper and the impact force is absorbed, the relative value becomes small with respect to the signal value when there is no sheet, and the determination is possible because the values are different. Further, the sheet material C is an OHP sheet, and since a vibration with a high frequency is detected because it is a relatively high resin, a signal having a high peak value is obtained. In the case of paper, the peak value has a variation of several percent of the above value due to the distribution of thickness due to unevenness (unevenness when scrubbing paper), etc. Accordingly, it is also possible to average the values in a plurality of detections and determine with higher accuracy.

  As described above, it is possible to determine that the sheet material is the paper by judging from the feature amounts of the respective outputs in the first external force application and the second external force application. Note that a sheet material having the same configuration (material, paper thickness, fiber density, moisture content, etc.) as that of the paper has the same mechanical characteristics and the same determination result can be obtained. In general, in a sheet material having different characteristics, for example, thick paper having high rigidity, which is a mechanical characteristic, the generated voltage near the end used as the feature amount of the region A is relatively large, and the peak voltage which is the feature amount of the region B is relatively Become smaller.

  The relationship between the behavior of the tip of the application member described above and the output of the pressure-sensitive element is determined by measuring the speed of the application member with a laser Doppler velocimeter (manufactured by Canon Inc., P-20Z type) and measuring the output waveform. Verification can be performed by using the observation of the behavior of the sheet material P by high-speed imaging as necessary.

(Example 3)
In this embodiment, a laser beam printer will be described as an example in the present embodiment as an image forming apparatus.

  Here, a configuration example in which the signal output apparatus according to the present invention is applied to a color laser beam printer to which electrophotography technology is applied as an image forming apparatus will be described with reference to FIG.

  Reference numeral 2701 denotes a recording material (hereinafter referred to as a transfer sheet) held in an accumulated state in the storage cassette 2702, and reference numeral 2703 denotes a feed roller for feeding the transfer sheet 1 positioned on the uppermost layer from the storage cassette 2702 one by one. , 2704 are registration rollers for temporarily stopping the leading edge of the transfer sheet 2701 fed by the feed roller 2703 and transferring the transfer sheet 2701 to the transfer drum 2705 in accordance with the transfer timing. 6 is a photosensitive drum that transfers a recorded image onto a transfer sheet 2701 held by a transfer drum 2705, and 2707 is cyan (C), magenta (M), yellow (Y), and black (Bk) toner in this example. Are accommodated in sleeves 7C, 7M, 7Y and 7Bk, and a color-specific developing device for forming a color-specific electrostatic latent image on the photosensitive drum 2706.

  Reference numeral 2708 denotes a laser scanner. The laser scanner 2708 modulates the intensity of the laser beam 2709 based on, for example, an image information signal sent from a host device (not shown), and the modulated laser beam 2709 is transferred to the photosensitive drum 2706. To form an electrostatic latent image for each color.

  Reference numeral 2710 denotes a fixing roller for fixing the toner image transferred onto the transfer sheet 1, 2711 denotes a discharge roller, and 2712 denotes a discharge tray. Reference numeral 2713 denotes a charger, and a potential for forming an electrostatic latent image is charged on the photosensitive drum 6 by the charger 2713.

  The electrostatic latent images of the respective colors formed on the photosensitive drum 6 with the configuration described above are selectively selected by the electric field formed by the voltage applied to the sleeves 7C to 7Bk and the surface potential charged by the charger 2713. The visualized image is transferred to a transfer sheet on the transfer drum 2705, and such a transfer operation is normally repeated for four colors Y, M, C, and Bk.

  In this embodiment, a signal output device is provided between the feeding roller 2703 and the registration roller 2704 for the sheet material. Reference numeral 1000 denotes an external force applying unit, 1040 denotes a separating means, and 1030 denotes an external force receiving unit having a recess.

  In this embodiment, the sheet material signal output device is installed between the paper tray and the transfer unit in the paper conveyance path, and the processing circuit is installed in a control circuit (not shown) in the printer. In this way, after obtaining an output signal corresponding to the physical properties of the sheet material, the power supplied for heating the fixing device was controlled as an image forming condition by comparison with a data table stored in advance. . According to the present embodiment, the heating condition of the fixing temperature can be appropriately controlled according to the physical properties of the sheet material.

  Although a laser printer has been shown as an example of an image forming apparatus, the present invention can be applied to other apparatuses that form images on sheet materials, including copiers using electrophotographic technology, printers such as ink ejection types and thermal transfer types. .

It is typical sectional drawing for demonstrating this invention. It is typical sectional drawing for demonstrating this invention. It is a table | surface for demonstrating this invention. It is a perspective view which shows an example of the external force receiving part applied to this invention. It is a perspective view which shows an example of the external force receiving part applied to this invention. It is a perspective view which shows an example of the external force receiving part applied to this invention. It is a perspective view which shows an example of the external force receiving part applied to this invention. It is typical sectional drawing for demonstrating this invention. It is a typical perspective view for demonstrating this invention. It is a flowchart figure for demonstrating this invention. It is a flowchart figure for demonstrating this invention. It is a block diagram for demonstrating this invention. It is typical sectional drawing for demonstrating this invention. It is a signal output diagram for demonstrating this invention. 1 is a schematic cross-sectional view when the present invention is applied to an image forming apparatus. It is a figure for demonstrating a prior art example. It is a figure for demonstrating a prior art example.

Explanation of symbols

1000 External force applying portion 1010 External force receiving portion 1020 Bottom portion of external force receiving portion 1030 Signal output portion 1040 Separation means 1025 Convex portion of concave external force receiving portion

Claims (7)

A signal output device relating to a sheet material,
An external force applying portion for applying an external force to the sheet material;
A concave external force receiving portion that receives the external force applied to the sheet material by the external force applying portion via the sheet material;
A signal output unit that outputs a signal corresponding to the physical properties of the sheet material according to the force received by the external force receiving unit via the sheet material;
Separating means for separating the sheet material from the bottom so that the sheet material is curved from the concave bottom side of the external force receiving portion toward the external force applying portion. Signal output device.   2. The signal output device according to claim 1, wherein the separating means is means for bending the sheet material on a bottom portion of the external force receiving portion in a direction away from the bottom portion.   The signal output device according to claim 1, wherein the bottom portion of the external force receiving portion is in contact with the other surface of the sheet material and receives a force from the external force applying portion.   The signal output device according to claim 1, wherein the signal corresponding to the physical property of the sheet material includes a signal related to the bending rigidity of the sheet material.   The signal output device according to claim 4, wherein the signal corresponding to the physical property of the sheet material includes a signal related to rigidity in the thickness direction of the sheet material.   An image forming condition setting unit for setting an image forming condition based on a signal output from the signal output device according to claim 1, and an image forming unit for performing image formation under conditions determined by the image forming condition setting unit. An image forming apparatus comprising: an image forming unit.   Based on a signal output from the signal output device according to claim 1, a conveyance condition setting unit for setting a conveyance condition for the sheet material, and conveyance of the sheet material according to a condition determined by the conveyance condition setting unit. A conveying device comprising: a conveying unit for performing.

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