JP2006184087A - Signal output device on sheet material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To acquire information on a sheet material, when information such as a numerical code is not attached beforehand to the sheet material. <P>SOLUTION: This signal output device on the sheet material has the first and second sensing means for allowing an impact application member to collide with the sheet material, and sensing the impact level of the sheet material. The device has characteristics wherein the first sensing means senses the impact level acquired by bending the sheet material, and the second sensing means senses the impact level acquired by compressing the sheet material in the thickness direction. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a signal output device related to a sheet material. The present invention also relates to a sheet material type detection device and a type detection method. More specifically, the present invention relates to an apparatus for detecting the type of sheet material (including paper medium and transparent resin sheet) used in an image forming apparatus such as a copying machine, a printer, or a FAX.

  A method for discriminating the type of sheet material is described in Japanese Patent Application Laid-Open No. 11-314443.

The technique described in the publication is a technique in which some numerical code or symbol is attached to the sheet material itself (hereinafter referred to as “marking method”). Information such as the numeric code is read by a sensor provided in the printer, and the printer uses this information to optimize the print mode.
Japanese Patent Laid-Open No. 11-314443

  However, in the above marking method, the type of a sheet material that is not attached with a numeric code or the like cannot be determined.

  Therefore, an object of the present invention is to provide a type detection method capable of detecting the type of sheet material without reducing the printing speed of the image forming apparatus even when information such as a numeric code is not attached to the sheet material in advance. And providing a type detection device.

  The signal output device related to the sheet material according to the present invention includes first and second sensing means for causing the impact applying member to collide with the sheet material and sensing the impact level of the sheet material, and the first sensing means includes: The impact level obtained by bending the sheet material is sensed, and the second sensing means senses the impact level obtained by compressing in the thickness direction of the sheet material.

  In the present invention, the first and second sensing means simultaneously sense the impact level on the sheet material, or the second sensing means senses more than the sensing by the first sensing means. It is characterized by being performed first.

The sheet material type detection method according to the present invention causes the impact applying member to collide with the sheet material,
First sensing means for sensing an impact level obtained by bending the sheet material with a pressure sensor such as a piezoelectric element;
The type of sheet material is discriminated by one or both of the second sensing means for sensing the impact level obtained by compressing the thickness direction of the sheet material with a pressure sensor such as a piezoelectric element. And

  According to the present invention, a signal relating to the bending rigidity (deflection) of the sheet material is obtained by the first sensing means, and the rigidity (compression) in the thickness direction of the sheet material is obtained by the second sensing means. The amount of information about the material can be increased.

  As shown in FIG. 1, in the present invention, when the impact applying member collides with the sheet material, the first impact having a concave shape as the impact receiving portion located at the position facing the impact applying member through the sheet material. It is characterized by including a receiving portion and a second impact receiving portion that does not have a concave shape.

  Information on how the sheet material bends (bending rigidity) can be obtained mainly by the first impact receiving portion. In this case, a pressure-sensitive element (first pressure-sensitive means) such as a piezoelectric element that detects the applied pressure may be disposed at a position facing the impact application unit, but preferably, as shown in FIG. It is preferable to arrange at a position away from the position facing the application unit and at a position where the bending of the sheet material can be detected.

  On the second impact receiving portion side, the pressure sensitive element (second sensing means) as described above is provided at a position facing the impact applying portion. Thereby, the information regarding the rigidity in the thickness direction of the sheet material can be acquired.

  In the case where the sensing is performed by the first sensing means, in order to prevent the bending deformation of the sheet material from affecting other parts, the sheet material by the first and second sensing means is applied to the sheet material. The impact level is sensed simultaneously, or preferably the sensing by the second sensing means is performed prior to the sensing by the first sensing means.

  Information on the physical properties of the sheet material can be obtained by using the information from the above two sensing means. By using this information, the sheet material is compared with the data in the storage unit in which the information on the sheet material is stored in advance. Even when the type of sheet material is determined or when the type of sheet material is not determined, the acquired signal is used to convey the sheet material (for example, the speed and the inter-roller pressure condition when conveyed by a roller) Image forming conditions on the sheet material (such as a fixing temperature when toner is fixed) can be appropriately set.

  According to the present invention, printing and printing are performed in an image forming process mode under optimum conditions corresponding to each sheet material type, so that a high-quality image forming apparatus can be provided.

Example 1
FIG. 1 is an enlarged cross-sectional view of a sheet conveying portion of an image forming apparatus provided with a sheet material sheet type detecting device according to the present invention, and a portion shows an impact level obtained by bending (bending) a sheet material. The first sensing means for sensing, FIG. B, shows the second sensing means for sensing the impact level obtained by compressing the thickness direction of the sheet material.

<Description of part a>
(Impact sensing means obtained by bending)
As shown in FIG. 1, the sheet material 5 passes between the sheet conveyance guides 6 and 7 formed with a certain gap, and forms an image at a predetermined speed (in the direction of the arrow in FIG. 1) by a conveyance roller (not shown). It is conveyed and guided to a process unit (not shown).

  The impact applying member 2 is formed of a material such as metal. Usually, the impact applying member 2 stands by at a solid line portion. The impact applying member 2 is held by a magnetic force generated when a current is supplied from the power source 51 to the coil 50.

  When the current of the power source 51 is cut off, the magnetic force of the coil 50 disappears, and the impact applying member 2 starts free fall due to gravity and collides with the sheet material 5 (FIG. 1, dotted line position). At this time, the sheet material 5 is bent and deformed by an impact force (FIG. 1, dotted line).

  The conveyance guide 7 is provided with a bending sensor 1 capable of converting an impact force into an electric signal at the recess 7a and a step portion on one side thereof, and when the sheet material 5 is bent by the impact force. The generated impact and pressure can be output as a voltage signal.

  When the sheet material 5 is conveyed by a conveyance roller (not shown) and passes through the vicinity of the bending detection sensor 1, the controller 101 controls the power source 51 to release the magnetic force. After impinging on the material 5, the impact pressure reaches the bending sensor 1 via the sheet material 5. The impact energy received by the sheet material 4 is output as an output voltage of the bending detection sensor 1. That is, a sheet material with high bending rigidity shows a high voltage value, and a sheet material with low bending rigidity shows a low voltage value.

The vertical axis in FIG. 2 represents the voltage output of the bending sensor 1 and
The horizontal axis represents time. For example, in the case of a sheet material of type A sheet (paper having a basis weight of 120 g / m ^{2 and} a thickness of 150 μm), the maximum output of the bending detection sensor 1 is Va.

In the case of the sheet material B type (paper having a basis weight of 80 g / m ^{2 and} a thickness of 100 μm), the maximum output of the bending detection sensor 1 is Vb.

In the case of the sheet material C type (paper having a paper basis weight of 60 g / m ^{2 and} a thickness of 80 μm), the maximum output of the bending detection sensor 1 is Vc.

  That is, the sheet material A of thick paper and high bending rigidity outputs a large maximum voltage of the sensor 1, and the sheet material C of thin paper and low bending rigidity outputs a small maximum voltage of the sensor 1.

  Thus, even if the impact energy applied to the sheet material by the impact applying member is the same, the rigidity of the sheet material in the bending direction depends on the basis weight of the sheet material (basis weight = weight per unit area) and the sheet material type. Because of the difference, the voltage of the bending sensor 1 is output differently depending on the type of sheet material.

  FIG. 3 is a schematic circuit configuration showing the relationship between the sheet material type device and the image forming apparatus. The voltage signal waveform from the bend detection sensor 1 is detected by the bend detection sensor detection circuit unit 501 with the maximum output voltage value. The bend sensing sheet type unit 502 in which the data table corresponding to each sheet material and the maximum voltage value is stored compares the result of the maximum value and determines the sheet material type.

  For example, as shown in FIG. 2, the data table in the bend sensing sheet type section 502 stores the sheet material A voltage range, the sheet material B voltage range, and the sheet material C voltage range. If the output is Va, the sheet material is in the class A voltage range, so the sheet material is determined to be class A, and if the maximum output is Vc, it is determined to be class C.

However, when the maximum output of the bending sensor 1 is Vz, such as the sheet material Z of FIG. 2 (paper having a basis weight of 100 g / m ^{2 and} a thickness of 130 μm), the maximum of the sheet material B is maximum. It becomes a value close to the output Vb, and the sheet material Z type can be judged only as the sheet material B type.

  There are many types of sheet materials used in the image forming apparatus. Therefore, there are cases where the maximum voltage output is very close to a different sheet material and cannot be classified as in the relationship between the above-described sheet material B type and Z type.

  For this reason, the sheet type is finally determined based on both values with the compression sensor in FIG.

<Description of part b>
(Means to sense the impact obtained by compression)
As shown in part b of FIG. 1, the impact applying member 4 is made of a material such as metal. Normally, the impact applying member 4 stands by at a solid line portion, and is held by a magnetic force generated by a power source 53 flowing through the coil 52.

  When the current of the power supply 53 is cut off, the magnetic force of the coil 52 is lost, and the impact applying member 4 starts free fall due to gravity and collides with the sheet material 5. At this time, the sheet material 5 is compressed and deformed in the thickness direction by an impact force.

  The opposing conveyance guide 7 is provided with a compression sensor 3 that can convert an impact pressure into an electrical signal, and the pressure after the sheet material 5 is compressed can be output as a voltage signal.

  When the sheet material 5 is conveyed by a conveyance roller (not shown) and passes through the vicinity of the compression detection sensor 3, the controller 101 controls the power source 53 to release the magnetic force, and the free fall of the impact applying member 4 starts at the next moment. Collides with the sheet material 5. Thereafter, the impact pressure and the vibration reach the compression sensor 3 through the sheet material 5. Impact energy that cannot be absorbed by the sheet material 5 is output as an output voltage of the compression sensor 3. That is, a sheet material having a small thickness direction compressive strain exhibits a high voltage value, and a sheet material having a large thickness direction compressive strain exhibits a low voltage value.

The vertical axis in FIG. 4 represents the voltage output of the compression detection sensor 3 in part b, and the horizontal axis represents time. In the case of the sheet material B (paper having a basis weight of 80 g / m ^{2 and} a thickness of 100 μm), the maximum output of the compression sensor 3 is Vb. In the case of the sheet material Z type (paper having a paper basis weight of 100 g / m ^{2 and} a thickness of 130 μm), the maximum output of the compression sensor 3 is Vz.

  That is, even if the sheet material has the same thickness, the type B of the sheet material having a small compressive strain outputs a large maximum output of the sensor 3 and outputs a small sheet material Z having a large compressive strain.

  Even if the impact energy applied to the sheet material by the impact application member is the same, the elastic modulus in the thickness direction of the sheet material depends on the basis weight of the sheet material (basis weight = weight per unit area) and the sheet material type. Therefore, the voltage of the compression sensor 3 is output differently depending on the type of sheet material.

  FIG. 3 is a schematic circuit configuration showing the relationship between the sheet material type device and the image forming apparatus.

  Similar to the bending sensing sheet type unit 502, the compression sensing sensor detection circuit unit 601 detects the maximum output voltage value of the voltage signal waveform from the compression sensing sensor 3. The bend sensing sheet type unit 602 in which the data table corresponding to each sheet material and the maximum voltage value is stored compares the result of the maximum value and determines the sheet material type.

  For example, the data table in the compression sensing sheet type section 602 stores the voltage range of each sheet material type such as the sheet material B type voltage range and the sheet material Z type voltage range as shown in FIG. If the maximum output from the sensor is Vb, it is in the sheet material A type voltage range, so it is determined that this sheet material is type B, and if the maximum output is Vz, it is determined that it is type Z.

  The sheet material B type and the sheet material Z type (in FIG. 2) cannot be classified because there is almost no voltage difference in the bending sensor 1, but can be obtained by compressing the thickness direction of the sheet material 5 in FIG. In the compression sensor 3, the sheet material B type indicates the Vb value, and the sheet material Z type indicates the Vz value and is output as a large voltage difference.

  As described above, the sheet type unit 510 processes the discrimination means results of both (a part and b part), determines the final sheet material type, and discriminates the sheet.

  When the discrimination of the type of sheet material is completed (FIG. 3), the recording mode control unit 503 adapts the conditions of the sheet material A (for example, the sheet material A), the sheet speed, the development condition, and the developer. Fixing conditions (temperature and temperature distribution) are determined. Each image forming process 504 is controlled to print or print in a recording mode optimum for the sheet material A type.

(Example 2)
FIG. 5 shows another embodiment of the bending detection sensor unit, and bending detection sensors 201a and 201b capable of converting an impact force into an electric signal are arranged at one step portion of the recess.

  The pressure at which the sheet material 5 is bent by the impact force can be output as a voltage signal.

  As for the impact application configuration, in the present invention, the impact energy is given to the sheet material by the method of holding by the magnetic force using the coil and the free fall, but if the configuration can give the impact to the sheet material, the spring Other methods using a cam or the like may be used.

Cross-sectional view of sheet material type detection device of the present invention Bending sensor output diagram of the present invention Compression sensor output diagram of the present invention Outline of sheet material classification device and image forming apparatus circuit configuration of the present invention Output diagram of the compression sensor of the present invention

Claims (2)

  First and second sensing means for sensing an impact level of the sheet material by causing the impact applying member to collide with the sheet material, and the first sensing means is an impact level obtained by bending the sheet material. And the second sensing means senses an impact level obtained by compressing in the thickness direction of the sheet material.   The first and second sensing means simultaneously sense the impact level on the sheet material, or the second sensing means senses before the first sensing means. The signal output device relating to the sheet material according to claim 1.

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