JP2004317358A - Surface property identification device, heating device and image forming device using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sensor protection means for simultaneously performing measures for preventing a sensor failure and improving the detection accuracy in actual use by installing, inside a printer, a sensor which brings a probe having a piezoelectric element into contact with a paper surface and detecting paper surface roughness. <P>SOLUTION: The probe having the piezoelectric element is contained in a sensor case having a protection function of the piezoelectric element surface and the probe tip end, a guide function for smoothly guiding a sheet shape object to be measured to the probe tip end, and a function for suppressing an excess displacement of the probes unnecessary for detection. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a surface property discriminating device for discriminating a difference in surface frictional resistance of an object to be measured, a difference in surface roughness and a difference in surface material, which are factors thereof, a heating device provided with the device, and an electrophotographic printer. And an image forming apparatus such as a copier, an ink jet printer, a thermal head printer, a dot impact printer, a facsimile, and a composite device thereof.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, various image forming apparatuses are generally used to form an image on a sheet-like recording material such as a plain paper, a postcard, a cardboard, an envelope, and a plastic thin plate for OHP. In apparatuses such as printers, copiers, and facsimile machines using a toner system, a toner image is formed on a recording material by electrostatic image forming means using toner as a developer, and then the recording material is heated and heated by a fixing means. The image is formed by applying pressure to melt and fix the toner image.
[0003]
In addition, other apparatuses such as printers, copiers, and facsimile machines using an ink jet system use ink as a developer, and use a large number of nozzles having minute orifices using mechanical or thermal reactions. An image is formed on a recording material by an image forming unit that ejects ink at a high speed from the configured recording head.
[0004]
Further, other devices such as printers, copiers, and facsimile machines using the thermal transfer method use an ink ribbon as a developer, and thermally transfer ink from the ink ribbon using a thermal head. An image is formed on the image.
[0005]
By the way, these apparatuses have been improved in recent years, and measures for high image quality and high processing speed have been realized by various means. At the same time, cost reduction measures have also been devised to reduce costs. It has become increasingly popular.
[0006]
However, the types of recording materials used in these image forming apparatuses are various, such as plain paper to high-grade paper with a special surface treatment for sealing, and resin sheets for OHP. As a result, it has become necessary to be able to form good images on any type of recording material used in various places, especially in image forming conditions. Is a very important factor.
[0007]
For example, in an apparatus adopting an electrophotographic system, when the surface of a recording material to be used is smooth (hereinafter, referred to as smooth paper) or rough (hereinafter, referred to as rough paper), a heat source is supplied from a heating source in a fixing unit. The heat transfer efficiency differs according to the difference in thermal resistance due to the difference in surface properties, and even if the rough paper is fixed at an appropriate fixing temperature with smooth paper, insufficient fixing is caused. It is necessary to fix at a high temperature. For this reason, in the current apparatus, the temperature at which the rough paper can be fixed is used as the standard fixing temperature, and the fixing is always performed at an excessive temperature for the smooth paper, and for the even rougher paper. Further, since a higher fixing temperature is required, a selection mode for allowing a user to change the setting of the fixing temperature when using such paper is provided.
[0008]
FIG. 2 shows a basic configuration of a printer adopting the electrophotographic system as a specific example of these.
[0009]
That is, FIG. 2 is a cross-sectional view of a main part of a conventional printer. In this printer, the surface of a photosensitive drum 2 is uniformly charged to a predetermined polarity by a charging roller 1 and then exposed by an exposure unit 3 such as a laser. A latent image is formed on the photosensitive drum 2 by discharging only the area where the photosensitive drum 2 is exposed. Then, this latent image is developed by the toner 5 of the developing device 4 and visualized as a toner image. That is, the toner 5 of the developing device 4 is frictionally charged between the developing blade 4a and the developing sleeve 4b to have the same polarity as the charged surface of the photosensitive drum 2, and DC and AC are applied at a developing gap portion where the photosensitive drum 2 and the developing sleeve 4b face each other. A bias is superimposed, and the toner 5 is selectively attached to a latent image forming portion of the photosensitive drum 2 while causing the toner 5 to float and vibrate by the action of an electric field. Then, the toner 5 is transferred by the transfer roller 6 and the photosensitive drum 2. The photosensitive drum 2 is conveyed to the nip by rotation of the photosensitive drum 2.
[0010]
On the other hand, after the recording material 7 such as paper on which an image is recorded is fed from the recording material storage box 7a 'to the vertical conveyance roller pair 7d by the paper supply roller pair 7c (the lower roller may be a pad), The sheet is conveyed to the pre-transfer conveying roller 7d 'by the vertical conveying roller pair 7d or conveyed to the pre-transfer conveying roller 7d' from the manual feed tray 7b by the sheet feeding roller pair 7c. Further, the pre-transfer conveying roller 7d 'conveys the sheet to a transfer nip portion at a predetermined entry angle between the upper transfer guide plate 9 and the lower transfer guide plate 9'. Before the recording material 7 is conveyed from the pre-transfer conveyance roller 7d 'to the transfer nip portion, the recording material 7 is rubbed with various members in contact with the recording material 7 until the recording material 7 is conveyed to this area. Since there is a possibility that the surface of the recording material 7 is charged, a static elimination brush 8 for removing such unnecessary electrification which may disturb an image when performing electrostatic recording is provided on the rear surface of the recording material 7 being conveyed. It is provided to contact the side and is grounded.
[0011]
In the transfer section, a high voltage having a polarity opposite to that of the toner 5 is applied to the transfer roller 6 on the back surface of the recording material 7 in order to electrostatically attract the toner 5 on the photosensitive drum 2 and move the toner 5 to the recording material 7 side. The toner 5 is electrostatically attracted to the back surface of the recording material 7 and the toner image is transferred to the recording material 7, and the back surface of the recording material 7 is charged to a polarity opposite to that of the toner 5 to keep the transferred toner 5. Is applied to the back surface of the recording material 7.
[0012]
Finally, the recording material 7 onto which the toner image has been transferred is conveyed to a fixing device 12 composed of a heating rotator 13 and a pressure roller 14 forming a nip portion, where the fixing temperature preset in the nip portion is reduced. The toner image is fixed by being heated and pressed while the temperature is controlled by a heater provided on the heating rotator 13 side to hold the toner image.
[0013]
Since a slight amount of foreign matter such as toner having a different polarity remains on the surface of the photosensitive drum 2 after the transfer of the toner image, the surface of the photosensitive drum 2 after passing through the transfer nip portion is cleaned by the cleaning container 10. After the attached matter is scraped off and cleaned by the cleaning blade 10a contacting the counter, the apparatus stands by for the next image formation.
[0014]
Since the components of the charging roller, the photosensitive drum, the developing container, and the cleaning container have a relatively short replacement cycle, a cartridge replacement type device in which these components can be replaced in units of a cartridge 11 is mainly used. are doing.
[0015]
Among the above processes, a contact heating type fixing device having good thermal efficiency and safety is widely known as an image fixing method. Conventionally, a release layer is mainly formed on a metal cylindrical core metal surface. Then, a heat fixing roller containing a halogen heater inside the cylinder and an elastic layer made of heat-resistant rubber formed on a metal core, and a pressure roller formed by forming a pressure-side release layer on the surface are pressed. A heat roller fixing device configured to be in contact has been used, but in recent years, as a method having a higher heating efficiency, a heat-resistant resin film having a low heat capacity is processed into a cylindrical shape in place of the heat fixing roller, and the surface thereof is formed. A film heating type fixing device is used in which a fixing film having a releasable layer formed thereon is used, and a ceramic heater is brought into contact with the film from the inside of a fixing nip portion to heat the film.
[0016]
From the viewpoint of promoting energy saving in recent years, this type of film heating type fixing device has a higher heat transfer efficiency than the conventional heat roller system using a cylindrical metal containing a halogen heater as a fixing roller, and the start-up of the apparatus is also possible. Attention has been paid to the fast method, and it has also been applied to higher-speed models.However, in this method, it is necessary to reduce the heat capacity of the heating surface of the fixing unit in order to emphasize the heating rate, and as a result It is difficult to form an elastic layer on the heating surface, and a hard heating surface is used. For this reason, this type of fixing system has a configuration in which a difference in heating efficiency easily occurs due to a difference in unevenness of the recording material surface.
[0017]
In various image forming apparatuses such as printers using such a fixing device, there is a problem that a difference in fixing property becomes conspicuous due to a difference in paper type with the increase in processing speed as described above. It is necessary for the user to input an appropriate fixing mode to the printer in advance according to the type of paper to be used by the user.
[0018]
However, forcing the user to select a mode in order to switch the fixing conditions each time according to the type of paper used increases the work load on the user, and when the selection mode is erroneous, the fixing for the print is performed. However, there is a possibility that power may be wasted due to insufficient heating, power may be wasted by excessive heating, image defects may occur due to high-temperature offset, or toner contamination of the fixing device may occur.
[0019]
Further, in a use environment in which a single network printer is shared by a plurality of users as in recent years, after one user performs mode setting switching according to the special paper, the special paper is used. May be left in the device, the mode may not match when used by other users who do not know that, and the above problem may occur due to improper fixing. Is getting higher.
[0020]
Regarding the number of fixing modes that can be set, there are strictly various levels in the actual paper smoothness, and it is impossible to set optimum conditions for each of them. The number of setting modes is limited by fixing papers having a range of smoothness collectively in the same mode, and there are cases where specific paper is fixed using more power than necessary. Depending on the combination, the fixing may be performed inefficiently.
[0021]
On the other hand, in an apparatus that employs the inkjet method, the required amount of ink differs when the recording material used is smooth paper and rough paper, and an image is printed on rough paper with an appropriate amount of ink on smooth paper. Even if it is formed, ink penetrates in the thickness direction of the paper, resulting in insufficient density. Therefore, it is necessary to discharge more ink to rough paper. For this reason, in the current apparatus, it is necessary for the user to perform an operation of causing the printer to recognize the paper type of the paper having different surface textures in advance.
[0022]
Also, in an apparatus adopting the thermal transfer method, the amount of required power is different when the recording material used is smooth paper and when rough paper is used. However, because of the large thermal resistance, the transferability of the ink is reduced, resulting in insufficient density.
[0023]
As described above, any of the current apparatuses consumes extra temperature, ink, and power to prevent the image quality from deteriorating due to the surface roughness of the recording material, or causes the image quality to degrade. In order to prevent this, it is necessary to switch these conditions according to the surface roughness of the recording material.However, at present, there are methods that require the user to change the settings and complicated configurations used in some devices. Only optical sensors that require signal processing have been considered, resulting in a significant increase in cost.
[0024]
For this reason, some proposals have been made for devices for detecting the roughness of the recording material surface and changing the image forming conditions in accordance with the detection result, and among them, relatively inexpensive and high-speed devices have been proposed. JP-A-2000-314618 and JP-A-2000-356507 disclose a detection principle capable of detecting the surface roughness of a recording material. In these proposals, the contact means that contacts the recording material surface detects physical phenomena such as vibration and rubbing noise caused by rubbing with the recording material surface, and detects a difference in the detected amount as a difference in surface roughness. As a specific configuration, there is proposed a configuration in which a piezoelectric element is provided in a contact unit and vibration is converted into an electric signal and detected.
[0025]
However, the above proposal does not disclose in detail the specific constitutional conditions necessary for a member (hereinafter, referred to as a probe) that is actually brought into contact with the recording material surface. Only one configuration is shown in which one end is fixed, and the downstream end is abutted so as not to be opposed to the oblique conveyance direction, and only this content actually realizes highly accurate detection. It was difficult.
[0026]
For this reason, the author has newly studied the sensor probe shape and mounting configuration in order to dramatically improve the surface property discrimination performance and make it practical with the detection method using a piezoelectric element. Very high discrimination performance can be obtained by providing a structure in which the contact portion can vibrate in the transport direction on the transport plane, and setting the tip contact portion at an angle that cuts into the measurement surface against the transport direction. As a configuration that realizes such a structure at the lowest cost without disturbing the paper conveyance, a probe having an S-shaped side shape obtained by bending a strip-shaped sheet metal twice is rotatably fixed to the rotation axis. As shown in the center of FIG. 2, this sensor is designed to detect whether paper is fed from either a paper cassette or a manual tray as shown in the center of FIG. Of the paper transfer path at the confluence of the paper transport path and the downstream side in the paper transport direction where the paper can be detected from the front side of the paper is attached to the optimal upper transfer guide 9 and evaluated. It was confirmed that high discrimination performance was obtained.
[0027]
More specifically, as shown in FIG. 3A, an S-shaped probe 15a having a piezoelectric element portion 15b formed in a flat portion has a non-transport side end attached to a probe holder 15c with a fixing screw 15d. The probe holder 15c is fixed so as to be rotatable on a probe rotating shaft 15e having a direction perpendicular to the carrying direction and having an axial direction in a direction parallel to the carrying plane, and the probe tip is carried around the probe rotating shaft 15e. It is pressed against the plane by a pressing means (not shown) with a contact pressure of about 10 to 30 g. Further, the probe rotating shaft 15e is fixed on a sensor holding plate 15g via a bearing 15f, and a transport flat plate 15h is provided on the paper transport path as a transport plane. FIG. 2C shows the positional relationship of these components when viewed from above, and the tip of the S-shaped surface property detection sensor 15 is provided at the center of the sensor holding plate 15g. A square hole is formed to make contact with the transport plane, and a signal line for extracting a detection signal is soldered from the surface of the piezoelectric element portion 15b and the surface of the sheet metal of the S-shaped probe 15a. The surface of the holding plate 15g is routed along the longitudinal direction.
[0028]
By using the S-shaped surface property detection sensor 15 configured as described above, the detection of the surface property of the conveyed paper can be completed at least before the fixing step, and the fixing control can be switched. Therefore, the user can use the apparatus without worrying about the type of paper to be used, and without causing an image defect and unnecessary power consumption.
[0029]
[Problems to be solved by the invention]
However, although the above-described configuration showed good discrimination and paper transportability at the basic study level, there were still incomplete portions in actually incorporating and using this sensor inside the apparatus. Each figure in FIG. 4 shows such a problem occurring in actual use,
If paper jams downstream of the sensor:
FIG. 4A is a schematic diagram for explaining a problem state when paper is jammed in a process after passing through the sensor, and shows a state in which the jammed paper is jammed in front of the sensor. If you attempt to remove the jammed paper and try to pull it out in the direction of the arrow in the figure, the tip of the deformed jammed paper will be caught on the sensor tip, and if you continue to pull it out, the sensor tip will be deformed or the piezoelectric element or fixed There is a risk of damaging the shaft.
When paper with a large curl at the leading end is passed:
When the paper with a large curl at the paper tip is passed through the detection portion of the sensor as it is, the paper tip is greatly jumped up by the curled paper tip as shown in FIG. After colliding with the lower part, etc., a large operation occurs that it collides again with the transport plane, causing damage due to direct collision of the piezoelectric element surface part, excessive stretching and bending of the signal line, peeling of the soldered part and its surroundings The risk of cracks in the piezoelectric element increases, and the longer the floating time, the shorter the time required to convey the paper surface within a certain period of time.
If paper jams upstream of the sensor:
This sensor has an S-shaped structure and its fixed end is rotatably fixed. Therefore, even if the height of the leading edge of the paper entering the sensor is conveyed to a certain height, the height of the paper is S-shaped. If the diameter is smaller than the diameter of the lower curved portion, the paper conveyance will not be an obstacle. However, if the paper leading end enters beyond the lower curved portion of the S-shape due to abnormally large curled paper or some paper conveyance failure, FIG. As shown in C), the force for pressing the sensor tip downward acts to stop the rotation of the sensor, hindering the advance of the paper as it is, causing a jam, and the sensor tip is pushed forward and the tip of the sensor is pushed forward. There is a risk of deformation or damage.
If the paper is weaker than the contact pressure of the sensor:
If the contact pressure of the sensor is set to be relatively high to increase the detection accuracy, depending on the set value, the sensor setting of the paper after passing may be possible when a thin paper such as thin paper is passed. There is a danger that local dent deformation as shown in FIG.
It is necessary to take into account that such problems can occur during actual product use.
[0030]
The present invention has been made in view of the above-described problem, and the object thereof is to eliminate the need for a user to select and set a paper type, and to perform good heat treatment and fixing even when paper having any surface roughness is used. An object of the present invention is to provide a heating device and an image forming apparatus using the surface property identification device capable of efficiently performing image formation, preventing failure and improving paper transport reliability.
[0031]
[Means for Solving the Problems]
In order to achieve the above object, the present invention provides a sheet material conveying means for conveying a sheet material, a probe having a piezoelectric element, a fixed shaft arranged at right angles to a conveying direction of the sheet material and parallel to a conveying plane, Pressurizing means for rotatably fixing a fixed end of the probe to the rotating shaft, and pressing the probe tip in a circumferential direction around the fixed shaft and in a direction opposite to the sheet material conveying direction. The sheet material is conveyed while the tip of the probe is in contact with the surface of the sheet material, so that the piezoelectric element portion induces irregularities on the surface of the sheet material and distortion due to vibration and impact having a strength corresponding to a friction coefficient. In the surface property identification device for generating an electrical signal and identifying the surface property of the sheet material surface based on the electrical signal intensity difference, the probe includes the piezoelectric element surface and the probe tip. And protection means, and the sheet material guide means for guiding the sheet material to the probe tip, characterized in that it is housed in a sensor case having a stopper means for restricting a displacement amount of the probe tip.
[0032]
Further, the present invention also provides an upper cover on the surface of the sensor case as the piezoelectric element surface protection means of the sensor case, a probe tip protection means, and a sheet material guide means for moving the probe right and left around the lower part of the sensor case. As a stopper means for restricting the amount of displacement of the probe tip portion and the probe tip portion, the probe tip portion is prevented from rotating more than necessary by contact with the non-piezoelectric element forming surface of the probe inside the sensor case. An upper stopper inner wall to be provided and a lower stopper inner wall for preventing the probe tip from rotating downward more than necessary, and the probe when the upward displacement is regulated by the upper stopper inner wall. The position of the leading end is changed downward by the inner surface of the seat guide rib and the inner wall of the lower stopper. There position of the probe tip when it is regulated, characterized in that it is each restricted to a position exposed by the length of the minimum necessary to identify from said sheet guide rib surface.
[0033]
Further, according to the present invention, the sensor case is fixed to a sensor case holding plate that holds the sensor case at a reference height from a transfer plane required for identification, and the upstream end of the sensor case holding plate in the transfer direction is a holding plate. The downstream end is rotatably fixed to the rotation axis for the holding plate, and the downstream end can be opened and closed about the rotation axis for the holding plate, and is applied to the holding plate height regulating member by the holding plate pressing means so as to maintain the reference height. The magnitude relationship between the pressure strength P1 of the holding plate pressing means and the pressure strength P2 of the pressing means at the tip of the probe is set so that P1≫P2, and the sheet conveying means is When the downstream end of the sensor case holding plate is closed, movement of the sheet material in the direction opposite to the conveying direction is prohibited, and when the downstream end of the sensor case holding plate is open, the sheet material is not opened. Move in any direction opposite to the transport direction It characterized by having a sheet material moving direction regulating means for the ability.
[0034]
Further, in the present invention, the sheet material movement direction regulating means uses a roller pair in which a conveyance roller rotating only in the sheet material conveyance direction is pressed against a driven roller as the sheet material conveyance means, and the sensor case holding plate is used. The cam mechanism is operated so as to release the pressing means of the roller pair in response to the operation of opening the downstream end of the roller pair.
[0035]
Further, according to the present invention, the sensor case is fixed to a sensor case holding plate for holding the sensor case at a reference height from a transfer plane required for identification, and the upstream end in the transfer direction of the sensor case holding plate is held. The holding plate pressing means is attached to the holding plate height regulating member so as to be rotatable on the plate rotation shaft, and the downstream end can be opened and closed around the holding plate rotation shaft to maintain the reference height. While being pressed against, the sensor case holding plate has a rotation axis for the sensor case at the downstream end in the transport direction of the sensor case, and the sensor case is rotatable about the rotation axis for the sensor case. The sensor case pressing means presses and abuts the sensor case pressing means on the sensor case holding plate at the upstream end in the transport direction of the sensor case. Pressurizing means The magnitude relationship between the pressure intensity P1 and the pressure intensity P2 of the pressure means at the probe tip is set such that P1 ≧ P3≫P2, and the sheet material conveying means is located downstream of the sensor case holding plate. Even in a state in which the end is closed, the sheet material can be moved in the direction opposite to the conveying direction, and the paper moved in the opposite direction moves the sheet guide rib downstream end surface in the sheet conveying direction and the probe tip in the conveying direction. The pressure intensity P3 of the sensor case pressurizing means is set such that the upstream end of the sensor case can move up and down about the sensor case rotation axis in accordance with the pressure to be pushed back in the opposite direction. It is characterized by the following.
[0036]
Further, according to the present invention, the sensor case has sheet pressing rollers for pressing the sheet on a conveyance plane on both left and right sides of the probe, and the diameter of the sheet pressing roller is at least a distance from the surface of the sheet guide rib at the tip of the probe. The position of the contact point between the sheet pressing roller and the transfer plane in the transfer direction is substantially longer than the exposed length, and the position of the contact point of the probe tip with the transfer plane substantially coincides with the position in the transfer direction. Fits inside the outline of the sheet holding roller and the sheet guide rib as viewed from the side in the conveyance direction, and always opens the sensor case holding plate and raises the upstream end of the sensor case holding plate so that the sheet press is always held down. The lower end of the roller is held at a position lower than the probe tip, and when closing the sensor case holding plate, Characterized in that it is configured to contact the serial sheet pressing roller in the conveying plane first.
[0037]
Further, the invention is characterized in that the inner wall of the stopper is formed of an elastic member.
[0038]
Further, in the present invention, the probe is rotatably fixed to the fixed shaft via a probe holder capable of attaching and detaching the probe, and the probe holder is provided on the probe holder as means for realizing the stopper function. A probe holder with a stopper function having a shape is used, and the probe holder with the stopper function is in contact with upper and lower inner walls of the sensor case near the fixed shaft.
[0039]
Further, according to the present invention, in the sensor case, the sensor case holding plate is housed upstream of the sheet guide rib with the sensor case holding plate closed, and the sensor case is moved to prevent the probe tip from being exposed when the sensor case holding plate is opened. And a probe protection shutter functioning to cover the probe.
[0040]
Further, according to the present invention, when the sheet guide ribs are viewed from the side in the conveyance direction, the conveyance required at least for the paper conveyance on the perpendicular line lowered from the center of the sensor case to the conveyance plane from the front and rear ends of the sensor case in the conveyance direction. The probe has an arcuate rib shape substantially coinciding with an arc of a circle passing through three points at a height position from a plane, and the contact position of the probe tip with the conveyance plane is conveyed from the lowest point of the arcuate rib. It is not provided on the downstream side in the direction.
[0041]
In addition, the present invention provides an S-shaped sheet metal which is bent at two places of a first bent part R1 and a second bent part R2 so that the tip of the metal sheet becomes S-shaped when viewed from the side in the transport direction as the probe. An S-shaped probe having a piezoelectric element formed on the surface of a flat portion between the fixed end of the S-shaped sheet metal and the first bent portion, and at least the most upstream point of the second bent portion R2 in the transport direction is the above-mentioned. It is housed inside the seat guide rib.
[0042]
By using the surface property identification device having the above characteristics, it is possible to prevent paper conveyance failure and device failure when using a conventional heating device or an image forming device using toner, ink, or an ink ribbon, and to prevent heating. It is possible to improve the detection accuracy of the surface characteristics of the recording material and the recording material, and to improve the reliability in optimizing the control conditions of each device according to each surface characteristic.
[0043]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.
[0044]
<Embodiment 1>
1 (A) to 1 (D) are a cross-sectional view, a front view, a cross-sectional view in a paper conveyance state, and a cross-sectional view in a jam occurrence state of the surface property identification device according to Embodiment 1 of the present invention. In FIG. 1A, the same elements as those shown in FIG. 3A are denoted by the same reference numerals.
[0045]
In the present embodiment, as shown in FIG. 1A, the upper portion of the S-shaped surface property detection sensor 15 is covered with an upper cover 16, and the lower portion is covered with a front guide rib 16b, a rear guide rib 16c, and a side guide rib 16d. A sensor case 16 is provided. The S-shaped surface property detection sensor 15 is rotatably mounted on a bearing (not shown) inside the sensor case, and a probe is provided in an opening surrounded by these guide ribs. The interior is set to be able to vibrate up and down about this rotation axis. Furthermore, the entire sensor case is fixed to a transfer upper guide / sensor case holding plate 15g 'in which a sensor mounting hole is machined in the transfer upper guide as a sensor case holding plate, and the transfer flat plate 15h uses a transfer lower guide plate to reduce the number of members. The internal space of the apparatus is effectively utilized. In particular, a holding plate rotation shaft 15i is provided at the upstream end of the paper transport upstream of the sensor case holding plate also serving as the upper transfer guide, and the downstream end of the holding plate is rotated by this rotation. A height regulating member (not shown) is provided so as to be openable and closable about a shaft, and is provided at a leading end of the holding plate so as to maintain a height required for paper conveyance in a closed state.
[0046]
The main dimensions of each of the above-mentioned components are as follows. The width of the probe is 4 mm, the size of the opening part where the probe moves up and down is 6 mm × 6 mm, the length of the probe flat part is 15 mm, and the piezoelectric The element has a size of 3 mm × 6 mm and is bonded at a position separated from the end of the first bent portion of the flat portion by 2 mm toward the fixed end. In addition, the probe tip is pressurized with a force of 10 g weight, and the sensor case holding plate is pressed against the tip with a force of 2 kg weight which is more than two orders of magnitude stronger. The stronger the tip is raised, the stronger the pressure.
[0047]
In the above configuration, as shown in FIG. 1A, the contour shape of the front guide rib 16b, the rear guide rib 16c, and the side guide rib 16d as viewed from the side in the transport direction is the minimum necessary for detecting the front end and the rear end of the case. Three positions above the transport plane by the exposed length of the probe tip (in this embodiment, the height is set to 0.5 mm, and the thickness of the paper to be passed is 0.3 mm at the maximum). The shape of the arc part of the passing circle is used. However, when the contact resistance between the paper surface and the rib surface becomes large, the radius of curvature of the front guide rib 16b and the rear guide rib 16c may be smaller than the radius of curvature of the left and right side guide ribs 16d, or the front guide rib 16b and the rear guide rib 16c. It is preferable that the corners at the lowermost point be rounded with a sufficiently large radius of curvature, or a roller member that can be driven by these corners may be provided. .
[0048]
The probe housed in the sensor case having the above-described shape has the probe tip pressed against the transport plane by a pressing unit (not shown) when the paper is not present in the detection unit. Is also in contact with the inner wall PL of the downward stopper provided at the downstream corner of the rear guide rib, and even if an external force is applied to push the probe tip downward, the probe tip will sink below the transport plane. Things are prevented.
[0049]
On the other hand, when the paper is passed through as shown in FIG. 1C and the tip of the probe is flipped up, first, even if the tip of the paper is greatly curled as in the conventional example, this configuration is used. In this case, the tip of the paper curled by the action of the rear and side guide ribs is corrected so as to be reduced to the minimum gap height required for detection (0.5 mm in this embodiment) and guided to the tip of the probe. At the maximum, the paper is pushed only by the leading edge of the gap height, thereby preventing the paper from being jumped up more than necessary. Even in the case of such a configuration, even if it is strongly flipped up, the probe sheet metal is positioned at the position of the upper stopper inner wall PH of the upper inner wall of the downstream side in the conveyance direction that is inclined obliquely of the upper cover that also protects the surface of the piezoelectric element. (1) The metal surface of the bent portion gradually contacts, and excessive rotation of the probe is stopped while suppressing generation of a large noise signal at the time of contact, so that it is possible to prevent damage to the piezoelectric element surface and suppress unnecessary movement of the probe. Become. Also, at this time, the dimensions of each member are set so that the position of the probe tip that has momentarily stopped is always stored inside the front, rear, left, and right guide ribs. To prevent the tip from deforming.
[0050]
Further, in the present configuration, when the paper jams on the downstream side of the sensor as shown in FIG. 1D, the latter half of the paper or the next paper collides one after another toward the leading end of the stopped paper, as shown in the figure. The force accumulates in a bellows shape in the direction perpendicular to the transport direction and acts to push up the entire sensor in the upward direction. Even in such a state, the opening of the sensor case of this configuration has a size of 10 mm × 10 mm or less. Since only a small hole is drilled, there is almost no danger that the tip of the probe will be pushed up by the paper, and if the accumulated pressure of the paper becomes high enough to cause deformation of the probe or the sensor case, this figure As described above, since the downstream end of the holding plate is opened upward about the shaft on the upstream side in the transport direction and acts to release the pressure of the paper, deformation and damage on the sensor case side can be completely prevented. Further, by opening and closing the sensor holding plate tip, it is easy to remove jammed paper accumulated in this portion.
[0051]
In this configuration, the opening / closing operation of the front end of the sensor case holding plate and the pressure releasing mechanism of the pre-transfer conveyance roller 7d 'provided upstream thereof are designed to work together. Only when it is opened upward, the pressure of the pre-transfer conveyance roller 7d 'is released and the paper can be easily pulled out to the upstream side. However, if the sensor case holding plate is kept closed, the pre-transfer conveyance roller 7d' is closed. The nip of the roller pair remains pressurized, and at the same time, the roller cannot rotate in the reverse direction, so it is very difficult to pull the paper sandwiched between the roller pair upstream in this state If the paper is forcibly pulled out, the paper itself will break at the nip of the roller, and if such a jam occurs in a normal usage, the user should open the sensor case holding plate upward. To remove unplug catching paper upstream to Tama, never large mechanical stresses on the probe tip is applied by this period of operation.
[0052]
<Embodiment 2>
5 (A), 5 (B), and 5 (C) are a cross-sectional view, a cross-sectional view of a state where a sensor holding plate is lifted, and a cross-sectional view where a sensor holding plate is lowered, respectively, showing a second embodiment of the present invention. is there. In FIG. 5A, the same elements as those shown in FIG. 1A are denoted by the same reference numerals.
[0053]
In the present embodiment, as shown in FIG. 5 (A), while using a sensor having substantially the same shape as that of the first embodiment, the lower stopper inner wall PL and the upper stopper inner wall PH in the sensor case of the first embodiment are formed. An elastic downward stopper 18 and an elastic upward stopper 17 each composed of an elastic member are provided at positions. In this embodiment, a high hardness rubber having a JisA hardness of 40 ° is used as the elastic member for the elastic downward stopper 18 so that this part is too soft and the stopper function when the probe tip is pulled back is not insufficient. On the other hand, as the elastic member for the elastic upward stopper 17, a soft low hardness rubber of 5 ° in JisA hardness, which can sufficiently absorb an impact so that a collision to this portion does not cause signal noise or breakage of the piezoelectric element, is used. Used. In particular, when the sensor case holding plate is greatly opened in the upward direction as shown in FIG. 5 (B) and then closed again as shown in FIG. 5 (C), the height of the holding plate tip is not lowered slowly without lowering it. If dropped, the probe tip will be accelerated by the force corresponding to the height, and the probe tip will collide with the transport plane, and may be strongly jumped upward due to the reaction. However, there is a risk that the sensor may be damaged or an excessive noise signal may be generated. However, such an inconvenience can be prevented by forming the upward stopper with a soft elastic body.
[0054]
With the above configuration, in the present embodiment, the durability of the sensor and the reliability of the detection signal can be further improved. Although rubber is used as the elastic material in this embodiment, it goes without saying that other buffer materials such as maltoprene and shock absorbing gel may be used.
[0055]
<Embodiment 3>
6 (A), 6 (B) and 6 (C) are a cross-sectional view, a cross-sectional view of a state where a sensor holding plate is lifted, and a cross-sectional view where a sensor holding plate is lowered, respectively, showing a third embodiment of the present invention. is there. In FIG. 6A, the same elements as those shown in FIG. 1A are denoted by the same reference numerals.
[0056]
In this embodiment, as shown in FIG. 6A, stoppers are provided at the upper and lower portions of the probe holder 15c instead of the upper stopper inner wall PH of the first embodiment while using a sensor having substantially the same shape as that of the first embodiment. A protrusion 15c 'is provided (a lower protrusion is not necessarily required as a downward stopper, and the lower surface of the probe holder may be used as it is in the same manner as in the above embodiment). Since it is provided closer to the rotation axis than the piezoelectric element forming portion, the probe tip is caused by a reaction when the tip of the sensor case holding plate is lifted as shown in FIG. 6B and dropped as shown in FIG. Even when the portion is flipped up, the probe can stop rotating by colliding with the inner wall of the sensor case with a smaller motion than stopping at the first bent portion of the probe. The sensor can be stopped without giving any damage or mechanical stress, so that the durability of the sensor can be improved and unnecessary collision signal noise can be suppressed. Furthermore, since the collision is made inside the piezoelectric element forming portion, the displacement difference due to the warpage of the sheet metal is almost eliminated at the front end and the rear end of the piezoelectric element portion, so that internal distortion is hardly induced, so that the collision noise in the piezoelectric element portion is reduced. The signal itself can be made smaller. In addition, by configuring the protrusions with an elastic member, it is possible to further reduce the collision noise.
[0057]
<Embodiment 4>
7 (A) and 7 (B) are a cross-sectional view of a paper surface property identification device and a cross-sectional view in a state where a sensor case is lifted, respectively, showing a fourth embodiment of the present invention. In FIG. 7A, the same elements as those shown in FIG. 6A are denoted by the same reference numerals.
[0058]
In the present embodiment, as shown in FIG. 7A, a sensor case rotation shaft 15j is newly provided at the downstream end of the sensor case in the transport direction while using a sensor having substantially the same configuration as that of the third embodiment. The sensor case is rotatably fixed on the sensor case holding plate via this rotation shaft, and the upstream end in the transport direction is pressed against the surface of the sensor holding plate with a force of 1 kg by a pressing means (not shown). Have been. By using the sensor configured as described above, when the paper jams on the downstream side in the transport direction of the sensor and the jammed paper is forcibly pulled out on the upstream side in the transport direction as shown in FIG. The withdrawal pressure mainly acts on the arc-shaped surface of the lower guide rib of the sensor case that faces downstream in the transport direction, and a part of this pressure is separated into components in the direction of lifting the upstream end of the sensor case upward by the arc-shaped action. When the pressure separated upward is greater than the pressure of the pressurizing means of the sensor case, the upstream end in the sensor case transport direction is lifted up as shown in FIG. Acts to make the tip of the probe escape from the jam paper pull-out path, so even if you try to pull the jammed paper in the reverse direction of the conveyance direction, Most force does not act on the parts, it is possible to prevent damage or deformation of the probe tip.
[0059]
At this time, the magnitude relation of the pressing strength of each member is as follows.
"Pressing means strength of sensor holding sheet metal> strength of pressing means of sensor case / strength of pressing means of probe"
Therefore, at the level of the upward pressure that the probe receives from the paper at the time of normal detection, the sensor case and the sensor case holding plate act almost as a fixed rigid body for the probe. The effects are almost negligible.
[0060]
<Embodiment 5>
8 (A), 8 (B), and 8 (C) are a cross-sectional view, a front view, and a cross-sectional view of a sensor case lifted state of the paper surface property identification apparatus according to Embodiment 5 of the present invention. In FIG. 8A, the same elements as those shown in FIG. 1A are denoted by the same reference numerals.
[0061]
In this embodiment, as shown in FIGS. 8A and 8B, the paper pressing roller 19 rotates the probe close to the left and right side surfaces of the probe while using a sensor having substantially the same configuration as that of the first embodiment. The roller arm 19 'fixed coaxially with the shaft and a roller pressing means (not shown) press-contact the transfer plane. As shown in the figure, the diameter of the paper holding roller is in contact with the transport plane at a position substantially coinciding with the contact position of the probe tip with the transport plane, and the diameter is at least at the probe tip when viewed from the side in the transport direction. The size is selected so that the portion exposed from the guide rib can be completely included. In this embodiment, a roller having a radius of curvature larger than the radius of curvature of the curved portion of the second bent portion of the probe is used. For this reason, the paper conveyed to the tip of the probe always comes into contact with the paper pressing roller first before contacting the tip of the probe, so the impact that the probe receives in the collision with the tip of the paper must be made in advance. It is possible to prevent a strong jumping-up of the probe by the paper tip and a local dent phenomenon of the paper tip due to the collision with the probe tip as in the conventional example and other embodiments. . In particular, the above-mentioned adverse effects are remarkable in a high-speed machine having a high paper conveyance speed, and this configuration is essential in a high-speed machine.
[0062]
Although the above-described drawings show the application of the paper pressing roller of the present embodiment to the configuration in which the rotation shaft is provided only on the sensor case holding plate, the paper pressing roller of the present embodiment is the same as that of the fourth embodiment. Needless to say, the present invention may be applied to a configuration in which a rotation shaft is provided at the downstream end of the sensor case as described above.In this case, the paper jammed on the downstream side in the transport direction of the probe is pulled out to the upstream side. However, the rollers are always in contact with the jammed paper to be pulled out first, pushing the jammed paper downward and encouraging the paper to move upstream, so that the force of the jammed paper that is pulled out does not directly act on the probe tip. Thus, deformation of the probe tip and damage to the sensor can be prevented more safely.
[0063]
In addition, these rollers are given enough pressure to hold down the paper being transported against the transport plane and sufficiently suppress paper flapping and curling at the tip, so that the probe tip has only pure irregularities on the paper surface. Detection becomes easier, and detection accuracy can be improved.
[0064]
When the tip of the sensor case holding plate is lifted as shown in FIG. 8 (C) by setting the movable range of the arm, the roller of this embodiment is always at a position lower than the lowest point of the tip of the probe by the distance t. The lowermost point of the roller is positioned so that when the tip of the sensor case holding plate is lowered, the roller always comes in contact with the transport plane first. Even if the probe is dropped after being lifted, the roller collides before the probe tip collides with the transport plane and the impact is reduced, and the probe comes into contact with the transport plane. Deformation of the probe tip and damage to the sensor can be prevented.
[0065]
<Embodiment 6>
9 (A), 9 (B) and 9 (C) are a cross-sectional view of a paper surface property identification device, a cross-sectional state in the middle of lifting a sensor case, and a cross-sectional view in a state where sensor case lifting is completed, respectively, showing a sixth embodiment of the present invention. . In FIG. 9A, the same elements as those shown in FIG. 1A are denoted by the same reference numerals.
[0066]
In this embodiment, as shown in FIG. 8A, while using a sensor and a sensor case having substantially the same configuration as those of the first embodiment, a probe protection shutter 20 and a shutter joint 20a, a shutter arm 20b, a shutter arm rotating shaft 20c, and a shutter tip roller 20d are provided, and the shutter arm is pressed by a pressing means (not shown) provided on the fixed shaft at a pressure similar to the probe contact pressure. The force which pushes down is always acting.
[0067]
In a normal state, the probe shutter 20 is housed in front of the sensor case as shown in FIG. 8A, and presses the paper conveyed by the roller at the tip (the diameter of the roller is also larger than the exposed length of the probe). Therefore, the paper is prevented from entering the upper part of the shutter.
[0068]
When the front end of the sensor case holding plate is lifted during jam clearance as shown in FIG. 9B, the shutter arm moves so that the probe protection shutter is lowered by the action of the pressing means (see FIG. 9B). At this time, the shutter arm moves through a groove (not shown) opened in the sensor case), and the shutter arm is set so that the shutter joint portion stops at the downstream end of the probe opening in the transport direction (by the groove of the arm). Either regulation or regulation by contacting the shutter joint with the front guide rib may be used.) After that, the probe protection shutter is set to face vertically downward by the weight of the roller at the tip, so the sensor case In the state where the holding plate tip is lifted vertically or more as shown in FIG. Since probe shutter moves completely to cover the opening of the probe, the user is forcibly unless lift the shutter upward, is no longer possible to touch the probe tip directly.
[0069]
On the other hand, when the front end of the sensor case holding plate is lowered after the jam processing, the pressing force applied to the front end of the sensor case holding plate is sufficiently larger than the pressing force acting on the shutter arm, so The roller at the tip of the contacted shutter acts to push up the shutter joint, and since the shutter arm is not strongly pressed against this force, the probe protection shutter bends at the shutter joint and the probe protection shutter transports the sensor case again. At the downstream end in the direction.
[0070]
In this embodiment, since the user cannot carelessly touch the probe, by using the probe protection structure in each of the above embodiments, the probe tip can be protected under any conditions. Thus, sufficient performance and durability can be maintained in any practical use.
[0071]
<Embodiment 7>
FIG. 10 is a sectional view of an ink jet type image forming apparatus according to Embodiment 7 of the present invention.
[0072]
In the present embodiment, a paper surface roughness detection sensor unit 25 in which components including a sensor case accommodating an S-shaped surface property detection sensor according to the present invention and a sensor case holding plate are unitized is applied to an ink jet printer. An inkjet printer 21 with a paper type detection function is configured. This apparatus has a paper feed tray 22, an inkjet paper feed roller 23, a paper guide 24, a pinch roller pair 26, a recording head 27, a platen 28, a paper discharge roller pair 29, and the like in this sectional structure. After receiving the signal, the paper on the paper feed tray 22 is conveyed to the pinch roller pair 26 by the paper feed roller 23, and the paper is conveyed to the platen 28 by a necessary amount by the operation of the pinch roller pair 26. The recording head 27 forms an image on the paper in the area corresponding to the feed, and the paper is sequentially fed by the operation of a pair of pinch rollers 26. The paper after the recording is nipped and conveyed by a pair of discharge rollers 29 to convey the entire image. After the formation is completed, the paper is finally discharged.
[0073]
In the present embodiment, the sensor unit 25 is disposed at a position facing the paper guide 24 between the paper feed roller pair 23 and the pinch roller pair 26, and the paper leading end from the paper feed unit at the beginning of the printing operation is moved. By detecting the surface roughness or frictional resistance of the paper by transporting the paper surface until the paper is transported to the pair of pinch rollers 26, the paper type is identified. By forming an image with a reduced amount, ink can be saved and bleeding to unnecessary parts can be suppressed.On the other hand, for paper with a rough surface, ink seepage into the lower layer of the paper should be considered. By switching the control so as to increase the amount of ink protrusion, it is possible to prevent the occurrence of problems such as a decrease in density and the like, and to control the amount of control of image forming conditions such as the amount of ink protrusion suitable for each paper type. And it has a function.
[0074]
As a sensor for this type of application, an optical sensor has already been developed in some models to detect the difference in glossiness on the paper surface using an optical sensor, and a device for identifying the paper type has been developed. Requires a large number of components, such as light sources, optical systems such as lenses and filters, and photoelectric conversion elements such as photodiodes and CCDs. Since accuracy is required, the cost tends to be high, and furthermore, the performance is greatly affected by contamination of the optical system.
[0075]
On the other hand, the sensor of the present invention can be configured at low cost with a general-purpose member in which a sheet metal, a piezoelectric element, and the like are widely used, and the surface of the detecting portion of the sensor is automatically cleaned by the paper surface each time paper is passed. Also, even if dirt or dust adheres to other parts, there is basically no effect on the performance, and even if there is, it will be shaken off by the generated vibration, so there is no need to worry about performance degradation due to dirt, It is also excellent in reliability.
[0076]
<Embodiment 8>
FIG. 11 is a sectional view of a thermal head type image forming apparatus according to the eighth embodiment of the present invention.
[0077]
In the present embodiment, a paper type detection function is provided by using a paper surface roughness detection sensor unit 25 in which components including a sensor case for housing the S-shaped surface property detection sensor according to the present invention and a sensor case holding plate are unitized. The thermal head printer 30 is included. The thermal head type image forming apparatus according to the present embodiment includes an ink ribbon 33, a pair of ink ribbon transport rollers 31, a thermal head 32, a head facing plate and paper transport guide 34, and the like. The paper 7 is transported by a paper feed roller and a paper transport roller (not shown) to the nip portion between the head facing plate and paper transport guide 34 and the ink ribbon transport roller 31 on the paper feed side, and is nipped between the ink ribbon 33 and the guide 34. After that, the ink layer 33 is conveyed to the head section together with the ink ribbon 33 while being in close contact with the ink ribbon 33, and the head section is supplied with necessary electric power according to a print signal to heat and melt the ink layer 33 'on the ink ribbon 33. After the ink image 33 ″ is formed on the paper by thermally transferring the paper to the paper surface, the paper is sequentially fed by the operation of the transport roller unit. It is configured to be issued.
[0078]
In the present embodiment, the sensor unit 25 is disposed at a position facing at least the guide portion 34 and the guide portion 34 before the nip portion of the ink ribbon transport roller 31 on the paper supply side, and the paper unit is moved from the paper supply portion at the beginning of the printing operation. By transporting the paper surface until the leading edge is transported to the nip, the surface roughness or frictional resistance of the paper is detected and the paper type is identified.For example, heat is applied to smooth paper. Since heat transfer can be performed with low power due to better conduction, control is switched to reduce the power supplied to the ink head.On the other hand, if the paper has a rough surface, the heat conductivity will decrease and the rough surface will be reduced. In order to transfer ink sufficiently, it is necessary to lower the viscosity of the ink.Therefore, it is possible to switch the control to lower the viscosity of the ink sufficiently with higher power. It is possible to switch between the control amount of the electric power.
[0079]
【The invention's effect】
As apparent from the above description, according to the present invention, the fixed end of the probe having the piezoelectric element is rotatably fixed to the fixed shaft arranged at right angles to the conveying direction of the sheet material surface and parallel to the conveying plane. The probe tip is conveyed while being in contact with the sheet material surface by using a pressing means for pressing the tip of the probe in a circumferential direction about the fixed axis and in a direction opposite to the conveying direction, so that the piezoelectric element is conveyed to the piezoelectric element portion. Surface property identification for inducing distortion due to vibration and impact having a strength corresponding to the unevenness and friction coefficient of the sheet material surface to generate an electric signal, and identifying the surface property of the sheet material surface based on the difference in the electric signal strength In the apparatus, the probe has a function of protecting the surface of the piezoelectric element and the tip of the probe, a sheet material guide function for smoothly guiding the sheet material to the tip of the probe, and the probe tip unnecessary for identification. The sensor case itself has a stopper function to suppress excessive displacement of the probe part, and the sensor case itself is rotatably fixed back and forth, and paper pressing rollers are provided on both sides of the probe tip. The probe surface is covered with a protective shutter in situations where the user may touch it during processing, so the probe tip is protected under any conditions, and in any situation where it is actually used The effect that sufficient performance and durability can be maintained can be obtained.
[Brief description of the drawings]
FIG. 1A is a cross-sectional view of a surface property identification device according to Embodiment 1 of the present invention,
(B) is a front view,
(C) is a sectional view of the paper transport state,
(D) is a cross-sectional view of a jam occurrence state.
It is.
FIG. 2 is a cross-sectional view of a conventional electrophotographic image forming apparatus.
FIG. 3A is a cross-sectional view of a conventional S-shaped surface property detection sensor on a paper transport path.
(B) is a top view
It is.
FIG. 4A is a cross-sectional view of a case where paper jams on the downstream side of a paper conveyance path of an S-shaped surface property detection sensor,
(B) is a cross-sectional view when the leading end curl paper has entered the paper conveyance path of the S-shaped surface property detection sensor,
(C) is a cross-sectional view when paper jams on the upstream side of the paper transport path of the S-shaped surface property detection sensor,
(D) is a top view when a dent occurs at the leading edge of the paper.
It is.
FIG. 5A is a cross-sectional view of a paper surface property identification device according to Embodiment 2 of the present invention;
(B) is a sectional view of the state where the sensor holding plate is lifted,
(C) is a sectional view of the sensor holding plate lowered.
It is.
FIG. 6A is a sectional view of a paper surface property identification device according to Embodiment 3 of the present invention,
(B) is a sectional view of the state where the sensor holding plate is lifted,
(C) is a sectional view of the sensor holding plate lowered.
It is.
FIG. 7A is a sectional view of a paper surface property identification device according to a fourth embodiment of the present invention,
(B) is a cross-sectional view of the sensor case lifted.
It is.
FIG. 8A is a sectional view of a paper surface property identification device according to a fifth embodiment of the present invention,
(B) is a top view,
(C) is a sectional view of the state where the sensor holding plate is lifted.
It is.
FIG. 9A is a sectional view of a paper surface property identification device according to Embodiment 6 of the present invention,
(B) is a sectional view of a state in which the sensor holding plate is being lifted,
(C) is a cross-sectional view of the state where the lifting of the sensor holding plate is completed.
It is.
FIG. 10 is a sectional view of an ink jet printer with a paper type detection device according to a seventh embodiment of the present invention.
FIG. 11 is a sectional view of a thermal head printer according to Embodiment 8 of the present invention.
[Explanation of symbols]
1 Charging roller
2 Photosensitive drum
3 Exposure means
4 Developing device
5 Toner
7 Recording materials
10 Transfer roller
12 Fixing unit
15 S-shaped surface property detection sensor
15c probe holder
15c 'stopper projection
15e Probe rotation axis
15g sensor holding plate
15g '15g' of sensor case holding plate for transfer guide
15h Transfer flat plate
15i Holding plate rotation axis
15j Rotary shaft for sensor case
16 Sensor case
16a Upper cover of sensor case
16b Front guide rib
16c rear guide rib
16d side guide rib
17 elastic upward stopper
18 elastic downward stopper
19 Paper holding roller
19 'Coro arm
20 Probe protection shutter
20a Shutter joint
20b Shutter arm
20c Shutter arm rotation axis
20d Shutter tip roller
21 Inkjet printer
27 Recording Head
30 Thermal head printer
33 Ink ribbon
32 thermal head

Claims (16)

Sheet material transporting means for transporting the sheet material, a probe having a piezoelectric element, a fixed axis arranged at right angles to the sheet material transport direction and parallel to a transport plane, and a fixed end of the probe with the rotation axis. Pressurizing means that is rotatably fixed and pressurizes the probe tip in a circumferential direction about the fixed axis and in a direction opposite to the sheet material conveyance direction, and places the probe tip on the sheet material surface. The sheet material is conveyed while being brought into contact with the piezoelectric element, thereby inducing a distortion due to vibration and impact having a strength corresponding to the unevenness of the surface of the sheet material and a coefficient of friction in the piezoelectric element to generate an electric signal. In the surface property identification device for identifying the surface property of the surface of the sheet material based on the difference in strength, the probe includes a protection unit for protecting the piezoelectric element surface and the probe tip, and And the sheet material guide means for guiding the serial sheet material, the surface property identification device, characterized in that accommodated in the sensor case having a stopper means for restricting a displacement amount of the probe tip. An upper cover on the surface of the sensor case as the piezoelectric element surface protection means of the sensor case, sheet guide ribs on the left and right sides of the probe movable range below the sensor case as the probe tip protection means and the sheet material guide means, An upper stopper inner wall for preventing the probe tip from rotating unnecessarily upward by contacting the non-piezoelectric element forming surface of the probe inside the sensor case as stopper means for restricting a displacement amount of the probe tip; A lower stopper inner wall for preventing the probe tip from rotating downward more than necessary is provided, and the position of the probe tip when the upward displacement is regulated by the upper stopper inner wall is The downward displacement is restricted by the inner surface of the lower stopper inside the seat guide rib. The probe tip position surface property identification device, characterized in that, each of which is restricted to a position exposed by the length of the minimum necessary to identify from said sheet guide rib surface of the case. 3. The sensor device according to claim 1, wherein the sensor case is fixed to a sensor case holding plate that holds the sensor case at a reference height from a transfer plane required for identification, and is upstream of the sensor case holding plate in a transfer direction. The end is rotatably fixed to the holding plate rotating shaft, and the downstream end is openable and closable about the holding plate rotating shaft, and is attached to the holding plate height regulating member so as to maintain the reference height. The pressing means is pressed against the pressing means, and the magnitude relationship between the pressing strength P1 of the holding plate pressing means and the pressing strength P2 of the pressing means at the probe tip is set so that P1≫P2. When the downstream end of the sensor case holding plate is closed, movement of the sheet material in the direction opposite to the conveying direction is prohibited, and the downstream end of the sensor case holding plate is opened. Then, the sheet material is moved in the opposite direction to the conveyance direction. Les surface property identification device characterized by having a sheet material moving direction regulating means also movable in the direction of. 4. The sensor case according to claim 3, wherein the sheet material moving direction regulating means uses a pair of rollers in which a conveying roller rotating only in the sheet material conveying direction is pressed against a driven roller as the sheet material conveying means. A surface property discriminating apparatus characterized in that a cam mechanism is operated so as to release a pressing means of the roller pair in response to an operation of opening a downstream end of the holding plate. 3. The sensor device according to claim 1, wherein the sensor case is fixed to a sensor case holding plate that holds the sensor case at a reference height from a transfer plane required for identification, and is upstream of the sensor case holding plate in a transfer direction. The end is rotatably fixed to the holding plate rotating shaft, and the downstream end is openable and closable about the holding plate rotating shaft, and is attached to the holding plate height regulating member so as to maintain the reference height. The sensor case holding plate has a rotation axis for the sensor case at the downstream end of the sensor case in the conveying direction, and the sensor case is centered on the rotation axis for the sensor case. The sensor case pressurizing means presses and abuts on the sensor case holding plate at the upstream end in the transport direction of the sensor case. And before The magnitude relationship between the pressing strength P1 of the holding plate pressing means and the pressing strength P2 of the pressing means at the probe tip is set such that P1 ≧ P3≫P2, and Even when the downstream end of the sensor case holding plate is closed, the sheet material can be moved in the direction opposite to the conveyance direction, and the paper moved in the opposite direction is the sheet conveyance direction downstream end face of the sheet guide rib and the sheet guide rib. The pressure of the sensor case pressurizing means is adjusted so that the upstream end of the sensor case can move up and down around the rotation axis for the sensor case in response to the pressure for pushing back the probe tip in the direction opposite to the transport direction. A surface property discriminating apparatus, wherein an intensity P3 is set. In each of the devices according to claims 3 to 5, the sensor case has sheet pressing rollers for pressing the sheet on a conveying plane on both left and right sides of the probe, and the diameter of the sheet pressing roller is at least the tip of the probe. The position of the contact position of the sheet pressing roller in the conveying direction longer than the exposed length from the sheet guide rib surface in the conveying direction is substantially the same as the position of the contact position of the probe tip in contact with the conveying plane in the conveying direction. Coincident, the tip of the probe always fits inside the contour viewed from the side in the conveyance direction formed by the sheet holding roller and the sheet guide rib, and opens the sensor case holding plate to move the upstream end of the sensor case holding plate. In the raised state, the lower end of the sheet holding roller is always held at a position lower than the tip of the probe, Surface property identification device when closing the scan retaining plate characterized in that it is configured to contact the conveying plane above the said sheet hold-down roller. 7. The surface property identification device according to claim 2, wherein the inner wall of the stopper is formed of an elastic member. 7. The apparatus according to claim 2, wherein the probe is rotatably fixed to the fixed shaft via a removable probe holder, and the probe is attached to the probe holder as means for realizing the stopper function. A probe holder having a stopper function provided with a shape for regulating rotation of the sensor case, wherein the probe holder with the stopper function contacts upper and lower inner walls of a sensor case near the fixed axis. 9. The apparatus according to claim 3, wherein the sensor case is housed upstream of the sheet guide rib in a state where the sensor case holding plate is closed, and the probe tip portion in a state where the sensor case holding plate is opened. A surface property identification device, comprising: a probe protection shutter that functions to cover the probe by moving so as to prevent exposure. 10. The sheet guide rib according to claim 3, wherein the sheet guide rib is configured such that, when viewed from a side surface in the conveyance direction, the sheet guide rib is configured to minimize paper conveyance on a vertical line lowered from the center of the sensor case to the conveyance plane from the center of the sensor case. The probe has an arcuate rib shape that substantially coincides with an arc of a circle passing through three points at a height position from the transport plane, and the contact position of the probe tip with the transport plane is the position of the arcuate rib. A surface property identification device, which is not provided downstream of the lowermost point in the transport direction. The probe in each of the devices according to Claims 3 to 10, wherein the probe is bent at two positions of a first bent portion R1 and a second bent portion R2 so that the tip portion of the metal sheet metal becomes S-shaped when viewed from the side in the transport direction. An S-shaped probe using an S-shaped sheet metal and having a piezoelectric element formed on the surface of a flat portion between a fixed end of the S-shaped sheet metal and the first bent portion, and at least a transport direction of the second bent portion R2. A surface property identification device, wherein the most upstream point is accommodated inside the sheet guide rib. The surface property identification device according to any one of claims 1 to 11, heat treatment means for contact-heating the material to be heated having passed through the surface property identification device, and the heat treatment according to an identification signal of the surface property identification device. A heating device comprising control means for controlling a heating temperature of the means. A surface property identification device according to any one of claims 1 to 11, an image forming means for forming a toner image on a recording material having passed through the surface property identification device, and heating and heating the recording material on which the toner image has been formed. An image forming apparatus comprising: a fixing unit that fixes the toner image on the recording material by applying pressure; and a control unit that controls a fixing temperature of the fixing unit in accordance with an identification signal of the surface property identification device. . A surface property identification device according to any one of claims 1 to 11, an image forming means for forming a toner image on a recording material having passed through the surface property identification device, and heating and heating the recording material on which the toner image has been formed. A fixing unit for fixing the toner image on the recording material by applying pressure; and a control unit for changing a heating time or a heating processing interval of the recording material according to an identification signal of the surface property identification device. Image forming apparatus. A surface property identification device according to any one of claims 1 to 11, an ink ejection type image forming unit that forms an image by ejecting ink onto a recording material that has passed through the surface property identification device, and the surface property identification device. An image forming apparatus comprising: a control unit that controls an ink discharge amount of the ink discharge type image forming unit according to an identification signal of the device. A surface transfer identification device according to any one of claims 1 to 11, and a thermal transfer image forming means for thermally transferring ink on an ink ribbon using a thermal head onto a recording material passing through the surface transfer identification device, An image forming apparatus comprising: a control unit that controls power supplied to the thermal head of the thermal transfer image forming unit in accordance with an identification signal of a surface property identification device.

Images