JP7003505B2 - Recording material discrimination sensor and image forming device - Google Patents

Description

The present invention relates to a recording material discrimination sensor and an image forming apparatus. More specifically, the present invention relates to a recording material discrimination sensor and an image forming apparatus used to discriminate the type of recording material.

The electrophotographic image forming apparatus includes an MFP (Multifunction Peripheral) having a scanner function, a facsimile function, a copying function, a printer function, a data communication function, and a server function, a facsimile machine, a copying machine, a printer, and the like. be.

In the conventional image forming apparatus, when the recording material is replenished to the cassette of the image forming apparatus, the user sets the type of the recording material based on the basis weight of the recording material through an operation panel or a PC (Personal Computer). I needed it. The image forming apparatus formed a high-quality image by selecting the optimum transport speed and fixing temperature for the set type of recording material. However, due to the difficulty and troublesomeness of the method of setting the type of recording material, the type of recording material may not be set accurately, resulting in paper jams and deterioration of the formed image.

Therefore, in order to reduce the burden on the user who sets the type of recording material, a technology has been proposed that measures the amount of transmitted light of the recording material and automatically detects the basis weight of the recording material based on the measured amount of transmitted light. There is. This technology utilizes the fact that the basis weight of the recording material can be inferred from the light transmittance.

In general, the surface properties and basis weight of the recording material are not uniform in the entire recording material, and unevenness exists depending on the position of the recording material. For this reason, when trying to detect the basis weight of the recording material based on the amount of transmitted light at one location of the recording material, the deviation from the average basis weight (actual basis weight) of the entire recording material becomes large, and the type of recording material There was a problem that the discrimination accuracy was low.

Therefore, techniques that can improve the accuracy of discriminating the type of recording material described above are disclosed in the following Patent Documents 1 and 2 and the like. In the following Patent Document 1, the recording material is irradiated with ultrasonic waves a plurality of times from the transmitting means while moving the recording material, and the ultrasonic waves transmitted through each of a plurality of different positions in the recording material are received by the receiving means. A technique for determining the surface property of a recording material is disclosed.

The following Patent Document 2 discloses a technique of photographing a plurality of light irradiation regions existing in a light irradiation region irradiated with light from a light source by using a plurality of image pickup elements.

Japanese Unexamined Patent Publication No. 2010-249615 Japanese Unexamined Patent Publication No. 2013-56771

However, in the technique of Patent Document 1, it is essential to irradiate ultrasonic waves while moving the recording material. Since the recording material tends to be displaced in the thickness direction during movement, the distance between each of the ultrasonic transmitting means and the receiving means and the recording material changes at each timing of irradiating the ultrasonic waves a plurality of times. As a result, the accuracy of the ultrasonic waves received by the receiving means was lowered, and the accuracy of discriminating the type of recording material was still low.

Further, in the technique of Patent Document 2, it is necessary to provide the same number of image pickup elements as a plurality of light imaging regions in order to photograph a plurality of light irradiation regions. As a result, there is a problem that the size of the configuration is increased and the manufacturing cost is increased.

The present invention is for solving the above-mentioned problems, and one object of the present invention is to provide a recording material discrimination sensor and an image forming apparatus capable of improving the discriminating accuracy of a recording material type.

Another object of the present invention is to provide a recording material discrimination sensor and an image forming apparatus capable of downsizing the configuration and reducing the manufacturing cost.

The recording material discrimination sensor according to one aspect of the present invention is a recording material discrimination sensor used for discriminating the type of recording material, and emits light to a plurality of different irradiation positions on the surface of the recording material. One irradiation means for irradiating and one light receiving means for receiving light from a plurality of irradiation positions are provided , and the irradiation means and the light receiving means overlap each other when viewed from a direction perpendicular to the surface of the recording material. Further, it is provided on a straight line connecting the irradiation means and the light receiving means, and further includes a light shielding means for blocking the light emitted from the irradiation means.

The recording material discrimination sensor according to another aspect of the present invention is a recording material discrimination sensor used for discriminating the type of recording material, and emits light to a plurality of different irradiation positions on the surface of the recording material. One irradiation means to irradiate, one light receiving means to receive light from a plurality of irradiation positions, and a guide for branching the light emitted from the irradiation means into a plurality of different optical paths and guiding them to each of the plurality of irradiation positions. The light receiving means includes an optical means , and the light receiving means receives light transmitted through the recording material at each of the plurality of irradiation positions.

In the recording material discrimination sensor, the light guide means preferably has a branching means for branching into a plurality of optical paths by reflecting the light emitted from the irradiating means and a plurality of light branched into a plurality of optical paths by the branching means. Includes a reflective means that reflects in the direction toward each of the irradiation positions of.

In the recording material discrimination sensor, the reflecting means is preferably a concave mirror.

In the recording material discrimination sensor, the light guide means preferably provides an irradiation-side light guide that internally reflects the light emitted from the irradiation means to branch into a plurality of optical paths and guide the light to each of the plurality of irradiation positions. include.

The recording material discrimination sensor preferably further includes a light receiving side light guide body that guides the light transmitted through the recording material at a plurality of irradiation positions to the light receiving means by internally reflecting the light.

In the recording material discrimination sensor, preferably, when viewed from a direction perpendicular to the surface of the recording material, the plurality of irradiation positions are all present on the same arc centered on the light receiving means.

In the recording material discrimination sensor, preferably, the irradiation means and the light receiving means are provided at overlapping positions when viewed from a direction perpendicular to the surface of the recording material, and are provided on a straight line connecting the irradiation means and the light receiving means. Further, a light-shielding means for blocking the light emitted from the irradiation means is provided.

In the recording material discrimination sensor, the light receiving means preferably further includes a reflected light guiding means that receives the reflected light reflected at a plurality of irradiation positions and guides the reflected light to the light receiving means.

The image forming apparatus according to another aspect of the present invention records based on the sensor for discriminating the recording material, the discriminating means for discriminating the type of the recording material based on the amount of light received by the light receiving means, and the discriminating result by the discriminating means. It is provided with an image forming means for forming an image on a material.

The image forming apparatus preferably includes a transport means for transporting the recording material, and further includes a transport means for stopping the transport of the recording material when the light receiving means receives light from a plurality of irradiation positions. ..

According to the present invention, it is possible to provide a recording material discrimination sensor and an image forming apparatus capable of improving the discriminating accuracy of the type of recording material. Further, according to the present invention, it is possible to provide a recording material discrimination sensor and an image forming apparatus capable of downsizing the configuration and reducing the manufacturing cost.

It is sectional drawing which shows typically the structure of the image forming apparatus 1 in 1st Embodiment of this invention. It is a side view which shows the structure of the vicinity of the recording material discrimination sensor 50 in the 1st Embodiment of this invention. In the first embodiment of the present invention, it is a top view which shows the positional relationship of some members of the recording material discrimination sensor 50 when viewed from the direction perpendicular to the surface of the recording material M. It is a side view which shows the structure of the recording material discrimination sensor 50 in the 1st modification of 1st Embodiment. It is a side view which shows the structure of the recording material discrimination sensor 50 in the 2nd modification of 1st Embodiment. It is a side view which shows the structure of the recording material discrimination sensor 50 in the 3rd modification of 1st Embodiment. It is a side view which shows the structure of the recording material discrimination sensor 50 in the 4th modification of 1st Embodiment. It is a side view which shows the structure of the recording material discrimination sensor 50 in 2nd Embodiment. It is a side view which shows the structure of the recording material discrimination sensor 50 in 3rd Embodiment.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

In the following embodiment, a case where the recording material discrimination sensor is mounted on the image forming apparatus will be described. Examples of the image forming apparatus include an MFP, a printer, a copying machine, a facsimile, and the like. Further, the recording material discrimination sensor may be mounted on a device other than the image forming device such as a recording material storage device and a post-processing device.

FIG. 1 is a cross-sectional view schematically showing the configuration of the image forming apparatus 1 according to the first embodiment of the present invention.

With reference to FIG. 1, the image forming apparatus 1 in the present embodiment is an MFP, which is a recording material conveying unit 10, a toner image forming unit 20 (an example of an image forming means), a fixing device 30, and a control unit. 40 and a sensor 50 for discriminating recording materials are provided.

The recording material transport unit 10 transports the recording material M along the transport path TR in the transport direction indicated by the arrow AR1. The recording material transport unit 10 includes a paper feed tray 11, a paper feed roller 12, a plurality of transport rollers 13a and 13b (an example of transport means), a paper discharge roller 14, and a paper discharge tray 15. The paper feed tray 11 accommodates a recording material M for forming an image. There may be a plurality of paper feed trays 11. The paper feed roller 12 is provided between the paper feed tray 11 and the transport path TR. Each of the plurality of transport rollers 13a and 13b is provided along the transport path TR. The transfer roller 13a is provided in the transfer path TR on the upstream side of the transfer roller 13b, which is a resist roller. The paper ejection roller 14 is provided at the most downstream portion of the transport path TR. The paper ejection tray 15 is provided at the uppermost portion of the image forming apparatus main body 1a.

The toner image forming unit 20 synthesizes four color images of Y (yellow), M (magenta), C (cyan), and K (black) by a so-called tandem method, and transfers the toner image to the recording material M to be conveyed. Form. The toner image forming unit 20 includes an image forming unit 21 for each YMCK color, an intermediate transfer belt 22, a primary transfer roller 23 for each YMCK color, and a secondary transfer roller 24.

The YMCK color image forming unit 21 includes a photoconductor drum 25, a charging roller 26, an exposure device 27, a developing device 28, a cleaning device 29, and the like. The photoconductor drum 25 is rotationally driven in the direction indicated by the arrow α in FIG. A charging roller 26, a developing device 28, and a cleaning device 29 are provided around the photoconductor drum 25. The charging roller 26 is provided close to the photoconductor drum 25. The exposure apparatus 27 is provided at the lower part of the photoconductor drum 25.

The intermediate transfer belt 22 is provided on the upper part of the image forming unit 21 of each color of YMCK. The intermediate transfer belt 22 has an annular shape and is bridged over the rotary roller 22a. The intermediate transfer belt 22 is rotationally driven in the direction indicated by the arrow β in FIG. Each of the primary transfer rollers 23 faces each of the photoconductor drums 25 with the intermediate transfer belt 22 interposed therebetween. The secondary transfer roller 24 is in contact with the intermediate transfer belt 22 in the transfer path TR.

The fixing device 30 fixes the toner image on the recording material M by transporting the recording material carrying the toner image along the transport path TR while grasping the recording material.

The image forming apparatus 1 rotates the photoconductor drum 25 and charges the surface of the photoconductor drum 25 with the charging roller 26. The image forming apparatus 1 exposes the surface of the charged photoconductor drum 25 according to the image forming information by the exposure apparatus 27, and forms an electrostatic latent image on the surface of the photoconductor drum 25.

Next, the image forming apparatus 1 supplies toner from the developing device 28 to the photoconductor drum 25 on which the electrostatic latent image is formed to develop the toner, and forms a toner image on the surface of the photoconductor drum 25.

Next, the image forming apparatus 1 sequentially transfers the toner image formed on the photoconductor drum 25 to the surface of the intermediate transfer belt 22 by using the primary transfer roller 23 (primary transfer). In the case of a full-color image, a toner image in which toner images of each YMCK color are combined is formed on the surface of the intermediate transfer belt 22.

The image forming apparatus 1 removes the toner remaining on the photoconductor drum 25 without being transferred to the intermediate transfer belt 22 by the cleaning apparatus 29.

Subsequently, the image forming apparatus 1 conveys the toner image formed on the surface of the intermediate transfer belt 22 to a position facing the secondary transfer roller 24 by the rotating roller 22a.

On the other hand, the image forming apparatus 1 feeds the recording material M housed in the paper feed tray 11 by the paper feed roller 12, and the intermediate transfer belt 22 is fed along the transport path TR by each of the plurality of transport rollers 13a and 13b. And the secondary transfer roller 24. Then, the image forming apparatus 1 transfers the toner image formed on the surface of the intermediate transfer belt 22 to the recording material M by the secondary transfer roller 24.

The image forming apparatus 1 guides the recording material M to which the toner image is transferred to the fixing device 30, and fixes the toner image to the recording material M by the fixing device 30. After that, the image forming apparatus 1 discharges the recording material M on which the toner image is fixed to the paper ejection tray 15 by the paper ejection roller 14.

The control unit 40 controls the entire image forming apparatus 1. The control unit 40 includes a CPU (Central Processing Unit) that executes a control program, a ROM (Read Only Memory) that stores the control program, a RAM (Random Access Memory) that constitutes a work area of the CPU, and the like. .. The control unit 40 includes a discriminating unit 41 (an example of discriminating means) for discriminating the type of recording material to be printed.

The recording material discrimination sensor 50 is used to discriminate the type of the recording material M. Under the control of the control unit 40, the recording material discrimination sensor 50 acquires information (light received light amount by the light receiving unit 52) necessary for the discriminating unit 41 to discriminate the type of the recording material M (here, the basis weight). do. The toner image forming unit 20 forms an image with respect to the recording material M under the conditions determined based on the discrimination result (type of the discriminated recording material M) by the discriminating unit 41.

FIG. 2 is a side view showing a configuration in the vicinity of the recording material discrimination sensor 50 according to the first embodiment of the present invention. FIG. 3 is a plan view showing the positional relationship of some members of the recording material discrimination sensor 50 when viewed from a direction perpendicular to the surface of the recording material M in the first embodiment of the present invention. be. In FIGS. 2 and 4 to 9, the thin dotted line indicates the width of the incident light on the recording material M. The solid arrow indicates the main traveling direction (optical path) of the light emitted from the light source 51 and received by the light receiving unit 52.

With reference to FIGS. 2 and 3, the recording material discrimination sensor 50 in the present embodiment includes a light source 51 (an example of an irradiation means), a light receiving unit 52 (an example of a light receiving means), and a light guide member 53 (a guide). An example of optical means) and. The light source 51 and the light guide member 53 are provided on the surface side (upper side in FIG. 2) of the recording material M. The light receiving portion 52 is provided on the back surface side (lower side in FIG. 2) of the recording material M.

The light source 51 is made of, for example, a laser device, a white LED (Light Emitting Diode), or the like. The light source 51 irradiates the surface of the recording material M with light having directivity in a direction perpendicular to the surface of the recording material M, and is composed of only one light source. The light source 51 causes the light LT 11 and LT 21 to be applied to the irradiation positions 61 and 62 (positions surrounded by a thick dotted line) of a plurality (here, two) different from each other on the surface of the recording material M by the action of the light guide member 53. Irradiate.

When viewed in FIG. 3, the light source 51 and the light receiving unit 52 are provided at overlapping positions. Further, the plurality of irradiation positions 61 and 62 are all present on the same arc AC centered on the light receiving portion 52. As a result, the distances between the irradiation positions 61 and 62 and the light source 51 are the same, so that the amount of light emitted to each of the irradiation positions 61 and 62 can be made uniform. Further, since the distances between the irradiation positions 61 and 62 and the light receiving unit 52 are also the same, the amount of light received from each of the irradiation positions 61 and 62 can be made uniform. As a result, the recording material discrimination sensor 50 can evenly acquire information from the plurality of irradiation positions 61 and 62 of the recording material M.

Even when the light sources 51 irradiate light to three or more irradiation positions different from each other, it is preferable that the irradiation positions are present on the same arc AC centered on the light receiving portion 52. As an example, when the light sources 51 irradiate four different irradiation positions 61 to 64 with light, it is preferable that the four irradiation positions 61 to 64 are provided on the same arc AC for the same reason as described above. Further, each of the irradiation positions 61 to 64 is provided on the arc AC at intervals such that the central angles centered on the light receiving portion 52 are equal (here, 90 degrees) so that the lights of the plurality of optical paths do not interfere with each other. Is preferable.

The light guide member 53 branches the light emitted from the light source 51 into a plurality of (here, two) optical paths (optical paths of the optical LT 11 and LT 12) different from each other, and guides the light to each of the plurality of irradiation positions 61 and 62. The light guide member 53 includes a branch member 531 (an example of a branch means) and reflection members 532 and 533 (an example of a reflection means).

The branch member 531 is provided at a position where it overlaps with the light source 51 and the light receiving portion 52 when viewed in FIG. The branching member 531 branches into a plurality of (here, two) optical paths (optical paths of the optical LT 11 and LT 12) by reflecting the light emitted from the light source 51. The branch member 531 includes inclined surfaces 531a and 531b inclined with respect to the surface of the recording material M. The inclined surface 531a is a surface that reflects the light emitted from the light source 51 in the direction of the reflecting member 532 and branches it into the optical path of the light LT 11. The inclined surface 531b is a surface that reflects the light emitted from the light source 51 in the direction of the reflecting member 533 and branches it into the optical path of the light LT 21.

The reflective members 532 and 533 are made of, for example, a plane mirror, and sandwich the branch member 531 in a substantially horizontal direction. The reflection member 532 reflects the light LT 11 in the direction toward the irradiation position 61. The reflection member 533 reflects the light LT 21 in the direction toward the irradiation position 62.

The light receiving unit 52 is made of, for example, a photodiode. The light receiving unit 52 receives light from a plurality of irradiation positions 61 and 62, and is composed of only one light receiving unit. In the present embodiment, the light receiving unit 52 receives the light LT12 and LT22 transmitted through the recording material M at each of the plurality of irradiation positions 61 and 62. The light receiving unit 52 outputs a voltage value according to the amount of received light to the discriminating unit 41. The light receiving unit 52 may output a voltage value corresponding to the average value of the received light LT12 and LT22, or may output a voltage value corresponding to the total amount of the received light LT12 and LT22.

Next, the operation of the recording material discrimination sensor 50 will be described. The recording material discrimination sensor 50 irradiates light from the light source 51, and the light receiving unit 52 receives the light LT12 and LT22 from the recording material M. The light transmitted through the recording material M becomes non-directional light (diffused light) and is isotropically emitted from the irradiation positions 61 and 62. The light LT12 and LT22 in the present embodiment are portions of the light transmitted through the recording material M that are incident on the light receiving portion 52. The light receiving unit 52 outputs a voltage value according to the amount of received light to the discriminating unit 41.

The amount of light received by the light receiving unit 52 is information necessary for the recording material discrimination sensor 50 to discriminate the type of the recording material M. Generally, the smaller the basis weight of the recording material M, the thinner the recording material M, and the larger the amount of light received by the light receiving unit 52. The discrimination unit 41 discriminates the type of the recording material M (here, the basis weight) based on the voltage value output from the light receiving unit 52 (the amount of light received by the light receiving unit 52).

The recording material discrimination sensor 50 in the present embodiment receives light from a plurality of different irradiation positions 61 and 62 on the surface of the recording material M. As a result, information on a plurality of locations on the surface of the recording material M can be acquired at once without moving the recording material, and the influence of the displacement of the recording material in the thickness direction due to the movement of the recording material and the influence of the displacement of the recording material in the thickness direction can be obtained. The effect of unevenness due to the position can be reduced. As a result, the accuracy of discriminating the type of recording material can be improved. Further, since information from a plurality of locations in the recording material M can be obtained at a time by using only one light source and one light receiving unit, it is possible to reduce the size of the configuration and the manufacturing cost.

When the recording material discrimination sensor 50 acquires information necessary for discriminating the type of the recording material M (in other words, when the light receiving unit 52 receives light from a plurality of irradiation positions 61 and 62). It is preferable that the transport rollers 13a and 13b stop the transport of the recording material M. As a result, the influence of the displacement of the recording material in the thickness direction due to the movement of the recording material can be eliminated, and the accuracy of discriminating the type of the recording material M can be further improved.

On the other hand, the recording material discrimination sensor 50 may acquire information on the recording material M being conveyed (the light receiving unit 52 may receive light from the recording material M being conveyed). In this case, the accuracy of discriminating the type of the recording material M can be further improved by acquiring the information of the recording material M being conveyed a plurality of times by the recording material discrimination sensor 50. Since the recording material discrimination sensor 50 can acquire information on a plurality of locations on the surface of the recording material M at once, even when acquiring information on the recording material M being conveyed, Patent Document 1 Compared with a technique such as a technique in which information at only one place can be acquired at a time, the influence of displacement of the recording material in the thickness direction due to the movement of the recording material can be reduced.

[Modified example of the first embodiment]

4 to 7 are side views showing the configuration of the recording material discrimination sensor 50 in the modified example of the first embodiment.

With reference to FIG. 4, in the recording material discrimination sensor 50 of the first modification, each of the reflective members 532 and 533 is made of a concave mirror. According to the first modification, the light emitted from the light source 51 can be focused on the plurality of irradiation positions 61 and 62, and the amount of light emitted to the plurality of irradiation positions 61 and 62 can be increased. .. As a result, the amount of light of the light source 51 can be reduced, and power saving can be achieved.

With reference to FIG. 5, the recording material discrimination sensor 50 in the second modification further includes a light-shielding member 54 (an example of light-shielding means). The light-shielding member 54 is provided on a straight line connecting the light source 51 and the light-receiving portion 52, and is in contact with the surface 531c of the branch member 531 on the light-receiving portion 52 side, for example, on the surface side (upper side in FIG. 5) of the recording material M. It is provided. The light-shielding member 54 blocks the light emitted from the light source 51 that leaks without being reflected by the reflecting member 532 or 533 and is applied to the recording material M. By providing the light-shielding member 54 as in the second modification, it is possible to prevent the light from shining on the portions other than the plurality of irradiation positions 61 and 62 on the surface of the recording material M, and it is possible to prevent the light from shining on the surface of the recording material M. The discrimination accuracy can be further improved.

With reference to FIG. 6, the light guide member 53 in the recording material discrimination sensor 50 in the third modification is the light guide bodies 534 and 535 instead of the branch member 531 and the reflection members 532 and 533 (FIG. 2). (An example of an irradiation side light guide body) is included. Each of the light guide bodies 534 and 535 has a cylindrical shape, and is provided on the surface side (upper side in FIG. 6) of the recording material M. The light guide body 534 is provided on a straight line connecting the light source 51 and the irradiation position 61, and by internally reflecting the light emitted from the light source 51, it is branched into the optical path of the optical LT 11 and guided to the irradiation position 61. .. The light guide body 535 is provided on a straight line connecting the light source 51 and the irradiation position 62, and by internally reflecting the light emitted from the light source 51, it is branched into the optical path of the optical LT 21 and guided to the irradiation position 62. ..

In the third modification, as in the first embodiment shown in FIG. 3, the plurality of irradiation positions 61 and 62 are all on the same arc AC centered on the light source 51 and the light receiving portion 52. It is preferable that it exists.

According to the third modification, the light focusing rate to the irradiation positions 61 and 62 can be increased by the light guide bodies 534 and 535. As a result, the amount of light of the light source 51 can be reduced, and power saving can be achieved.

With reference to FIG. 7, the recording material discrimination sensor 50 in the fourth modification has the light guide bodies 551 and 552 (an example of the light receiving side light guide body) in addition to the configuration of the third modification shown in FIG. ) Is included. Each of the light guide bodies 551 and 552 has a cylindrical shape and is provided on the back surface side (lower side in FIG. 7) of the recording material M. The light guide body 551 guides the light transmitted through the recording material M at the irradiation position 61 to the light receiving unit 52 by internally reflecting the light. The light guide body 552 guides the light transmitted through the recording material M at the irradiation position 62 to the light receiving unit 52 by internally reflecting the light.

According to the fourth modification, the light collection rate of the light transmitted through the recording material M at the plurality of irradiation positions 61 and 62 can be increased by the light guide bodies 551 and 552. As a result, the amount of light of the light source 51 can be reduced, and power saving can be achieved.

The configurations and operations other than the above of the image forming apparatus and the recording material discrimination sensor in the first to fourth modifications are the same as the configurations and operations of the image forming apparatus and the recording material discrimination sensor in the first embodiment. Since it is the same, the explanation is not repeated.

[Second Embodiment]

FIG. 8 is a side view showing the configuration of the recording material discrimination sensor 50 according to the second embodiment.

With reference to FIG. 8, the recording material discrimination sensor 50 in the present embodiment includes a light source 51, a light receiving unit 52, and a light shielding member 54. The light source 51 and the light-shielding member 54 are provided on the surface side (upper side in FIG. 8) of the recording material M. The light receiving portion 52 is provided on the back surface side (lower side in FIG. 8) of the recording material M.

The light-shielding member 54 is on a straight line connecting the light source 51 and the light-receiving portion 52, and is provided on the surface side (upper side in FIG. 8) of the recording material M. The light-shielding member 54 is preferably provided at a position as close as possible to the recording material M.

The light source 51 irradiates the surface of the recording material M with non-directional light (diffused light), and is composed of only one light source. The light source 51 irradiates the light LT 11 and the LT 21 to a plurality of (here, two) irradiation positions 61 and 62 different from each other on the surface of the recording material M by the action of the light shielding member 54.

That is, the light-shielding member 54 blocks the light emitted from the light source 51 to a wide area on the surface of the recording material M toward the region between the irradiation position 61 and the irradiation position 62. As a result, the light from the light source 51 is applied to the irradiation positions 61 and 62.

The light receiving unit 52 receives light from a plurality of irradiation positions 61 and 62, and is composed of only one light receiving unit. In the present embodiment, the light receiving unit 52 receives the light LT12 and LT22 transmitted through the recording material M at each of the plurality of irradiation positions 61 and 62. The light receiving unit 52 outputs a voltage value according to the amount of received light to the discriminating unit 41.

Since the configurations and operations other than the above of the image forming apparatus and the recording material discrimination sensor in the present embodiment are the same as the configurations and operations of the image forming apparatus and the recording material discrimination sensor in the first embodiment. , The explanation is not repeated.

According to the present embodiment, the accuracy of discriminating the type of recording material can be improved as in the first embodiment. In addition, it is possible to reduce the size of the configuration and the manufacturing cost.

[Third Embodiment]

FIG. 9 is a side view showing the configuration of the recording material discrimination sensor 50 according to the third embodiment.

With reference to FIG. 9, the recording material discrimination sensor 50 in the present embodiment includes a light source 51, a light receiving unit 52, a light shielding member 54, and a light guide member 56 (an example of reflected light light guide means). There is. The light source 51, the light receiving portion 52, the light shielding member 54, and the light guide member 56 are all provided on the surface side (upper side in FIG. 9) of the recording material M.

The light source 51 irradiates the surface of the recording material M with non-directional light (diffused light), and is composed of only one light source. The light source 51 irradiates the light LT 11 and the LT 21 to a plurality of (here, two) irradiation positions 61 and 62 different from each other on the surface of the recording material M by the action of the light shielding member 54.

That is, the light-shielding member 54 blocks the light emitted from the light source 51 to a wide area on the surface of the recording material M toward the region between the irradiation position 61 and the irradiation position 62. As a result, the light from the light source 51 is applied to the plurality of irradiation positions 61 and 62.

The light receiving unit 52 receives light from a plurality of irradiation positions 61 and 62, and is composed of only one light receiving unit. In the present embodiment, the light receiving unit 52 receives the light LT13 and LT23 reflected by each of the plurality of irradiation positions 61 and 62 on the surface of the recording material M by the action of the light guide member 56. The light receiving unit 52 outputs a voltage value according to the amount of received light to the discriminating unit 41. The light source 51 and the light receiving portion 52 are provided at overlapping positions when viewed from a direction perpendicular to the surface of the recording material M. The distance between the light receiving unit 52 and the recording material M is longer than the distance between the light source 51 and the recording material M.

The light guide member 56 guides the light LT13 and LT23 reflected at each of the irradiation positions 61 and 62 to the light receiving unit 52. The light guide member 56 includes reflective members 561 and 562. The reflective members 561 and 562 are present on the same circumference centered on the light receiving portion 52 when viewed from a direction perpendicular to the surface of the recording material M. The reflection member 561 guides the light LT 13 reflected at the irradiation position 61 to the light receiving unit 52 by reflecting the light LT 13. The reflection member 562 guides the light LT 23 reflected at the irradiation position 62 to the light receiving unit 52 by reflecting the light LT 23.

Since the configurations and operations other than the above of the image forming apparatus and the recording material discrimination sensor in the present embodiment are the same as the configurations and operations of the image forming apparatus and the recording material discrimination sensor in the first embodiment. , The explanation is not repeated.

The recording material discrimination sensor 50 of the present embodiment acquires the received light amount of the reflected light at a plurality of irradiation positions 61 and 62. According to the present embodiment, the accuracy of discriminating the type of recording material can be improved as in the first embodiment. In addition, it is possible to reduce the size of the configuration and the manufacturing cost.

[others]

In the above-described embodiment, the case where the discriminating unit 41 discriminates the basis weight of the recording material M based on the light receiving light amount of the light receiving unit 52 is shown, but the discriminating unit 41 records based on the light receiving light amount of the light receiving unit 52. The type of the material M (thickness, whiteness, glossiness, etc.) may be discriminated, and the recording material discriminating sensor of the present invention may be any one used to discriminate the type of the recording material.

The above-described embodiments and modifications can be combined as appropriate. For example, the configuration in which the light guide members 551 and 552 in FIG. 7 are provided may be combined with the configuration in which the light guide member 53 shown in FIG. 2 is provided. Further, the configuration in which the light guide bodies 551 and 552 shown in FIG. 7 are provided may be combined with the configuration in which the convex mirror shown in FIG. 4 is provided, the configuration in which the light shielding member 54 shown in FIG. 5 is provided, and the like. Further, in contrast to the configuration provided with the light guide member 56 shown in FIG. 6, the configuration provided with the convex mirror shown in FIG. 4, the configuration provided with the light shielding member 54 shown in FIG. 5, or the reflected light shown in FIG. 9 is received. Configurations and the like may be combined.

The embodiments and variations described above should be considered exemplary and not restrictive in all respects. The scope of the present invention is shown by the scope of claims rather than the above description, and is intended to include all modifications within the meaning and scope equivalent to the scope of claims.

1 Image forming device 1a Image forming device main body 10 Recording material transport section 11 Paper feed tray 12 Paper feed rollers 13a, 13b Transport rollers (an example of transport means)
14 Paper ejection roller 15 Paper ejection tray 20 Toner image forming unit (an example of image forming means)
21 Image forming unit 22 Intermediate transfer belt 22a Rotating roller 23 Primary transfer roller 24 Secondary transfer roller 25 Photoreceptor drum 26 Charging roller 27 Exposure device 28 Developing device 29 Cleaning device 30 Fixing device 40 Control unit 41 Discrimination unit (an example of discrimination means) )
50 Recording material discrimination sensor 51 Light source (example of irradiation means)
52 Light receiving part (example of light receiving means)
53,56 Light guide member (example of light guide means and reflected light light guide means)
54 Light-shielding member (an example of light-shielding means)
61-64 Irradiation position 531 Branching member (example of branching means)
531a, 531b Inclined surface in the branch member 531c Surface on the light receiving part side in the branch member 532, 533, 561,562 Reflective member (example of reflective means)
534,535,551,552 light guide (example of irradiation side light guide and light receiving side light guide)
Arc arc centered on the AC light receiving part LT11, LT12, LT13, LT21, LT22, LT23 Optical M Recording material TR Transport path

Claims (11)

A recording material discrimination sensor used to discriminate the type of recording material.
One irradiation means that irradiates light to a plurality of different irradiation positions on the surface of the recording material, and
It is provided with one light receiving means for receiving light from the plurality of irradiation positions .
The irradiation means and the light receiving means are provided at overlapping positions when viewed from a direction perpendicular to the surface of the recording material.
A recording material discrimination sensor provided on a straight line connecting the irradiation means and the light receiving means and further provided with a light blocking means for blocking the light emitted from the irradiation means . A recording material discrimination sensor used to discriminate the type of recording material.
One irradiation means that irradiates light to a plurality of different irradiation positions on the surface of the recording material, and
One light receiving means for receiving light from the plurality of irradiation positions, and
It is provided with a light guide means for branching the light emitted from the irradiation means into a plurality of different optical paths and guiding the light to each of the plurality of irradiation positions.
The light receiving means is a sensor for discriminating recording materials, which receives light transmitted through the recording material at each of the plurality of irradiation positions. The light guide means is
A branching means for branching into the plurality of optical paths by reflecting the light emitted from the irradiating means, and a branching means.
The sensor for discriminating recording materials according to claim 2, further comprising a reflecting means for reflecting light branched into the plurality of optical paths by the branching means in a direction toward each of the plurality of irradiation positions. The sensor for discriminating recording materials according to claim 3, wherein the reflecting means comprises a concave mirror. The second aspect of the present invention includes an irradiation-side light guide that internally reflects the light emitted from the irradiation means to branch into the plurality of optical paths and guide the light to each of the plurality of irradiation positions. The described recording material discrimination sensor. The recording according to any one of claims 2 to 5, further comprising a light receiving side light guide body that guides each of the light transmitted through the recording material at the plurality of irradiation positions to the light receiving means by internally reflecting the light. Material discrimination sensor. The invention according to any one of claims 2 to 6, wherein the plurality of irradiation positions are all present on the same arc centered on the light receiving means when viewed from a direction perpendicular to the surface of the recording material. Sensor for discriminating recording materials. The irradiation means and the light receiving means are provided at overlapping positions when viewed from a direction perpendicular to the surface of the recording material.
The recording material discrimination sensor according to any one of claims 2 to 7, further comprising a light-shielding means provided on a straight line connecting the irradiation means and the light-receiving means and blocking the light emitted from the irradiation means. .. The light receiving means receives the reflected light reflected at the plurality of irradiation positions and receives the reflected light.
The sensor for discriminating recording materials according to claim 1, further comprising a reflected light guiding means for guiding the reflected light to the light receiving means. The sensor for discriminating recording materials according to any one of claims 1 to 9,
A discriminating means for discriminating the type of the recording material based on the amount of light received by the light receiving means, and
An image forming apparatus including an image forming means for forming an image on the recording material based on a discrimination result by the discriminating means. The claim further comprises a transporting means for transporting the recording material, further comprising a transporting means for stopping the transport of the recording material when the light receiving means receives light from the plurality of irradiation positions. 10. The image forming apparatus according to 10.

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