Image forming apparatuses include a paper feed device to feed printing paper. The paper feed device includes a paper feed cassette to hold a stack of printing paper, and may in some cases include a manual feed tray to enable a user to manually feed printing paper.
In the following description, with reference to the drawings, the same reference numbers are assigned to the same components or to similar components having the same function, and overlapping description is omitted.
The terms “left” and “right” represent respective directions when a drawing is viewed from the front, and they are not always in agreement with directions during actual use of a device. Scale reductions in the drawings are not always based on actual dimensions and the drawings are sometimes emphasized partially for explanation of the operations and effects of the present disclosure.
Example image forming apparatuses including a paper feed cassette and a manual feed tray will be described, in which a paper level of printing paper remaining in the paper feed cassette may be detected, in order to improve convenience for a user, and in which the size of the printing paper in the manual feed tray may be detected to control printing operations.
An example paper feed device may include a tray to feed printing paper, a magnetic force generation element, a 3-dimensional (3D) magnetic sensor, and a controller. The tray includes a movable element that is movable in relation to the printing paper. The 3D magnetic sensor detects changes in the density of magnetic flux generated by the magnetic force generation element in three axes, respectively. The controller determines the position of the movable element based on a detection signal received from the 3D magnetic sensor. Either the magnetic force generation element or the 3D magnetic sensor is attached to the movable element. The magnetic force generation element is combined with the 3D magnetic sensor to determine the three-dimensional position of the magnetic force generation element, so as to provide more flexibility as to the location where a sensor for detection is attached, and simplify the configuration for determining the position of the movable element.
According to an example, the magnetic force generation element can be a magnet. In addition, the tray may be a manual feed tray, and the movable element may include a pair of side guides mounted on the manual feed tray, so that the controller can determine a paper size based on the position of the side guides. The magnetic force generation element can be attached to the side guides.
According to examples, the manual feed tray is openably/closably attached to a housing of the image forming apparatus to be mounted with the paper feed device. The 3D magnetic sensor is attached to the housing. The controller can determine an open state or a closed state of the manual feed tray based on the detection signal. In addition, when the manual feed tray is in a closed state, the controller can prompt a user to open the manual feed tray.
According to examples, the controller can detect the densities of magnetic flux generated from the magnetic force generation element with the 3D magnetic sensor when the pair of side guides is at a first position and a second position, respectively, and can additionally determine the paper size by use of the respective detection signals generated from the 3D magnetic sensor.
According to examples, the controller can calibrate the 3D magnetic sensor based on a temperature around the magnetic force generation element. In addition, the controller can calibrate the 3D magnetic sensor based on a difference between a stored temperature around the magnetic force generation element and the current temperature.
According to examples, the tray is a paper feed cassette, the movable element is a stack support plate disposed in the paper feed cassette, and the controller can determine a paper level in the paper feed cassette based on the position of the stack support plate.
According to examples, the magnetic force generation element can be disposed at one of a bottom of the stack support plate and a side wall of a cassette receiver portion of an image forming apparatus to be mounted with the paper feed cassette. The 3D magnetic sensor can be disposed at the other among the bottom of the stack support plate and the side wall of the cassette receiver portion of the image forming apparatus to be mounted with the paper feed cassette. In some examples, the 3D magnetic sensor is disposed to the side wall of the cassette receiver portion, and the position of the 3D magnetic sensor can correspond to a position between a maximum position and an empty position of the printing paper stacked on the stack support plate. Further, the controller can notify a user of a decrease in the paper level based on the determined paper level.
An example image forming apparatus may have a paper feed device that includes a tray to feed printing paper, a magnetic force generation element, a 3D magnetic sensor and a controller. The tray may include a movable element that is movable in relation to the printing paper. The 3D magnetic sensor may detect changes in the density of magnetic flux generated by the magnetic force generation element in three axes, respectively. The controller may determine the position of the movable element based on a detection signal received from the 3D magnetic sensor. Either one of the magnetic force generation element or the 3D magnetic sensor is attached to the movable element. This combined use of the magnetic force generation element and the 3D magnetic sensor allows the position of the magnetic force generation element, for example, to be three-dimensionally determined by the 3D magnetic sensor, and provide more freedom on the location to which a sensor for detection is attached, in addition to simplifying the configuration for determining the position.
According to examples, the magnetic force generation element can be a magnet.
Example paper feed devices for an image forming apparatus will be described.
With reference to
The paper feed device 20 includes a sensor S1 to detect whether or not printing paper is present in the paper feed cassette 21. In addition, the paper feed device 20 can further include an upper limit sensor S2 to detect that the uppermost sheet of the printing paper 2 in the stack of the printing paper 2 reaches the predetermined height position H. Any suitable sensor that can detect whether or not printing paper is present in the paper feed cassette 21 can be used as the sensor S1. In addition, any suitable sensor that can detect a height position of the uppermost sheet of the printing paper 2 in the stack of the printing paper 2, can be used as the upper limit sensor S2. In some examples, the sensor S1 and the upper limit sensor S2 can include an optical sensor of transmission type or reflection type.
The paper feed device 20 can additionally include a pair of paper feed rollers R2, conveyance rollers R3 and register rollers R6. The pair of paper feed rollers R2 send out (or convey), along the conveyance path L toward the conveyance rollers R3, the printing paper 2 that has been lifted out by the paper feed roller R1. The conveyance rollers R3 convey the printing paper 2 which has been conveyed from the paper feed rollers R2, to the register rollers R6 along the conveyance path L. The register rollers R6 align the printing paper 2 and convey the printing paper 2 to the image forming portion 10. In addition, the paper feed device 20 can include an edge sensor (or tip sensor) S4 to detect whether the printing paper 2 was lifted out from the paper feed cassette 21 in accordance with a normal operation of the paper feed device 20. The edge sensor S4 can detect a edge of the printing paper 2 conveyed from the paper feed rollers R2. Additionally, the paper feed device 20 can include a sensor S7 to align the printing paper with an image. The edge sensor S4 and the sensor S7 can be, for example, an optical sensor of reflection type.
The paper elevating mechanism 22 may include any suitable mechanism or device that can move the stack of the printing paper 2 or the stack support plate 23 up and down. In some examples, the paper elevating mechanism 22 can be composed of a rack and pinion that can be driven by an elevating motor M2 and can move the stack support plate 23 up and down. In other examples, the paper elevating mechanism 22 can include a spring capable of energizing the stack support plate 23 toward the paper feed roller R1.
In addition, the paper feed device 20 can include a manual feed tray 30 to allow a user to perform manual paper feeding, so as to feed paper manually. The paper feed device 20 includes a paper feed roller R4 to put out (or lift out) a printing paper 2 disposed on the manual feed tray 30 and convey the printing paper 2 to the conveyance rollers R6. In addition, the paper feed device 20 includes a sensor S5 to detect whether or not printing paper is present in the manual feed tray 30. The sensor S5 may be any suitable sensor that can detect whether or not printing paper is present in the manual feed tray 30. In some examples, the sensor S5 can be an optical sensor of transmission or reflection type. The manual feed tray 30 will be further described in connection with
In some examples, the paper feed device 20 is controlled by a controller 50. The controller 50 can be a microprocessor-based controller capable of connecting with a memory via, for example, a communication bus. In some examples, the controller 50 includes the memory. The memory can store machine-executable instruction, and information from various sensors attached to the image forming apparatus 1. The controller 50 can execute instructions, and can further control an operation of the image forming apparatus 1 in accordance with theses instructions. The controller 50 can be a controller to control operations of various constituent elements inside the image forming apparatus 1, or a controller dedicated to control operations of various constituent elements of the paper feed device 20.
When a user uses the manual feed tray 30 to perform printing, it may be useful to have the image forming apparatus 1 automatically detect a size or width of the printing paper 2 disposed on the manual feed tray 30, to optimize the control of toner developing and fixing in the image forming portion 10. In addition, in the image forming apparatus 1, in order to prevent printing from coming to a halt caused by use of all of the printing paper 2 in the paper feed cassette 21, it may be useful to detect a level of paper in the paper feed cassette 21 and to notify a user of it.
According to examples, a magnetic force generation element is combined with and a 3D magnetic sensor that measures a density of magnetic flux generated by the magnetic force generation element in three axes, in order to detect a size of the printing paper 2 disposed on the manual feed tray 30 and to detect a paper level of the printing paper 2 in the paper feed cassette 21.
One of the pair of side guides 31 has a magnetic force generation element P2 attached thereto. In some examples, the magnetic force generation element P2 can be a permanent magnet having both surfaces magnetized. In other examples, the magnetic force generation element P2 may be an electromagnet. Hereinafter, an example in which the magnetic force generation element P2 is a permanent magnet having both surfaces magnetized will be described. In some examples, a 3D magnetic sensor S6 to measure a density of magnetic flux generated by the permanent magnet P2 in three axes is attached to a bottom surface 4 of the manual feed tray receiver portion 3 (see also
The controller 50 can determine the position of the side guide 31 based on a detection signal received from the 3D magnetic sensor S6, and by extrapolation, can determine a size or width of the printing paper 2 disposed on the manual feed tray 30. The determination of this position and the size of the printing paper 2 will be further described below.
With reference to
The controller 50 can determine the position of the stack support plate 23 as a movable element based on a detection signal received from the 3D magnetic sensor S3, and further can determine a paper level (amount of remaining printing paper) of the printing paper 2 in the paper feed cassette. The determination of this position or the paper level of the printing paper 2 in the paper feed cassette will be described further below.
According to the graphs of
θ=arctan (density of magnetic flux in the X axis direction/density of magnetic flux in the Y axis direction).
With reference to
The position of the side guide 31 in the manual feed tray 30 may be obtained based on the angle θ determined as described above. According to examples, the position of the side guides 31 may be determined from a value for the angle θ, based on values for the angle θ obtained when the side guides 31 are located at a first position and at a second position, respectively. In some examples, the position of the side guides 31 may be determined from a value for the angle θ, based on values for the angle θ obtained when the pair of side guides 31 are spaced apart by a maximum distance and when the pair of side guides 31 are spaced by a minimum distance.
A factor K1 to determine the position of the side guide 31 is calculated by the following equation:
K1=(maximum width in which the side guide is movable)/(magnet angle B−magnet angle A)
In order for a user to place the printing paper 2 on the manual feed tray 30, the user can move the side guides 31 to a given position. In this state, the 3D magnetic sensor S6 may measure a density of magnetic flux generated by the permanent magnet P2 that is attached to the side guide 31. At that position, the angle θ1 of the permanent magnet P2 viewed from the 3D magnetic sensor S6 in the XY plane can be determined with the equation arctan (density of magnetic flux in the X axis direction/density of magnetic flux in the Y axis direction), as described above in connection with
Position of side guide=Factor K1×Magnet angle C
The determined position of the side guide 31 enables the controller 50 to grasp a width of the printing paper 2. In addition, the controller 50 measures a time period from on-state of the sensor S7 to off-state thereof, which is caused by disposing the printing paper 2 on the manual feed tray 30 and then conveying it, and can thereby determine a length of the printing paper 2.
With reference to
At 910, the controller 50 displays on the UI 40 an indication to prompt the user to space the side guides 31 of the manual feed tray 30 with a maximum distance and press a confirmation button. The operation proceeds to 912 where the controller 50 determines whether or not the confirmation button is pressed. If the button is not pressed, the operation returns to 910. If the button is pressed, the operation proceeds to 914. At 914, the controller 50 measures a density of magnetic flux generated by the permanent magnet P2 in the three axes by the 3D magnetic sensor S6, and calculates and stores the magnet angle A in the memory. Next, the operation proceeds to 916 where the controller 50 displays on the UI 40 an indication to prompt the user to space the side guides 31 of the manual feed tray 30 with the minimum distance and to press the confirmation button. The operation proceeds to 918 where the controller 50 determines whether or not the confirmation button is pressed. If the button is not pressed, the operation returns to 916. If the button is pressed, the operation proceeds to 920. At 920, the controller 50 measures via the 3D magnetic sensor S6 a density of magnetic flux generated by the permanent magnet P2 in the three axes, calculates the magnet angle B, and stores the magnet angle B in the memory. At 922, the controller 50 calculates the factor K1 as described above and stores the factor K1 in the memory. At 923, when calculating the factor K1, the controller 50 measures an ambient temperature around the permanent magnet P2 and stores the ambient temperature as a temperature T1 in the memory.
At 924, the controller 50 uses the sensor S5 to detect whether the printing paper 2 is disposed on the manual feed tray 30. When the paper is not disposed, the operation proceeds to 930 where the controller 50 displays on the UI 40 an indication to prompt the user to place the printing paper 2 on the manual feed tray 30. Next, the operation returns to 924. If the printing paper 2 is disposed, the operation proceeds to 926 where the controller 50 measures the density of magnetic flux generated by the permanent magnet P2 in the three axes by the 3D magnetic sensor S6 and calculates the magnet angle C through linear calibration or the like as described above. Next, the operation proceeds to 928 where the controller 50 uses the factor K1 and the magnet angle C to calculate the position of the side guides as described above, thereby determining a width of the printing paper. The operation ends at 932.
An operation of determining the position of the stack support plate 23 in the paper feed cassette 21, that is the paper level in the paper feed cassette by using an angle θ as described above in connection with
The controller 50 of the image forming apparatus 1 measures densities of magnetic flux in the three axes by the 3D magnetic sensor S3 in the state where the paper feed cassette 21 is not mounted in the cassette receiver portion 24 of the image forming apparatus 1 as shown in
In some examples, in the state where the paper feed cassette 21 is mounted in the cassette receiver portion 24 of the image forming apparatus 1 and an amount of the printing paper 2 placed on the stack support plate 23 in the paper feed cassette 21 is maximum as shown in
In some examples, in the state where the paper feed cassette 21 is mounted in the cassette receiver portion 24 of the image forming apparatus 1 and no printing paper 2 is placed in the paper feed cassette 21 as shown in
The factor K2 for acquiring the position of the stack support plate 23 in the paper feed cassette 21, that is the paper level in the paper feed cassette is calculated by the following equation:
Factor K2=(maximum of paper level)/(magnet angle F−magnet angle E)
Printing operations performed by the image forming apparatus 1 consume the printing paper 2 in the paper feed cassette 21, causing the stack support plate 23 to move to a given position. At that time, a density of magnetic flux generated by the permanent magnet P1 attached to the stack support plate 23 is measured in three axes by the 3D magnetic sensor S3. At that position, the angle θ3 of the permanent magnet P1 viewed from the 3D magnetic sensor S3 in the XY plane can be calculated as described above in connection with
Paper level=factor K2×(magnet angle F−magnet angle G)
Based on the determined paper level, the controller 50 can notify a user of a decrease of the paper level through the user interface 40.
With reference to
At 1122, the controller 50 determines whether or not the factor K2 is calculated. The factor K2 is calculated at 1118 described below and stored in the memory. If the factor K2 is calculated, the operation proceeds to 1124; or if factor K2 is not calculated, the operation proceeds to 1126. At 1124, the controller 50 measures a current temperature around the permanent magnet P1 and stores it as a current temperature T2′ in the memory. In some examples, such temperature measurement can be performed by use of a temperature sensor (e.g., a thermometer) placed adjacent the permanent magnet P1. The controller 50 determines an absolute value of a difference between the current temperature T2′ and a temperature T2 which is described further below. The absolute value is expressed as |T2′−T2|, and determines whether the absolute value is greater than a defined value (or threshold value). The defined value can be in the range of 5 to 30, for example 10. If |T2′−T2| exceeds the defined value, the operation proceeds to 1126. If the defined value is not exceeded, the operation proceeds to 1110.
At 1126, an indication to prompt the user to pull out the paper feed cassette 21 from the cassette receiver portion 24 is displayed on the UI 40. Next, the operation proceeds to 1128 where the controller 50 determines whether or not the paper feed cassette 21 is mounted or inserted in the cassette receiver portion 24. If the paper feed cassette 21 is not inserted, the operation proceeds to 1130; and if the paper feed cassette 21 is inserted, the determination at 1128 enters a loop until the paper feed cassette 21 is pulled out. At 1130, the controller 50 measures respective densities of magnetic flux Dx, Dy and Dz (collectively referred to as density of magnetic flux D) in three axes by use of the 3D magnetic sensor S3, and stores these measured values in the memory. The controller 50 can update the densities of magnetic flux stored in the memory whenever the density of magnetic flux D is measured. At 1132, the controller 50 displays an indication on the UI40 so as to prompt the user to remove all of the printing paper 2 from the paper feed cassette 21 (so as to make the paper feed cassette empty) and insert the paper feed cassette 21 into the cassette receiver portion 24. At 1134, the controller 50 determines whether or not the paper feed cassette 21 is inserted into the cassette receiver portion 24. If the paper feed cassette 21 is inserted, the operation proceeds to 1136; and if the paper feed cassette 21 is not inserted, the determination at 1134 enters a loop until the paper feed cassette 21 is inserted. At 1136, the controller 50 detects whether or not the printing paper 2 is present in the paper feed cassette 21, and thus whether or not the paper feed cassette is empty by use of the sensor S1. If the paper feed cassette 21 is empty, the operation proceeds to 1138; and if the paper feed cassette 21 is not empty, the operation returns to 1132. At 1138, the controller 50 measures densities of magnetic flux generated from the permanent magnet P1 in three axes, respectively, by use of the 3D magnetic sensor S3 to calculate the magnet angle F, and stores the magnet angle F in the memory. At 1140, the controller 50 displays an indication on the UI40 so as to prompt the user to place the maximum amount of the printing paper 2 on the paper feed cassette 21 and insert the paper feed cassette 21 into the cassette receiver portion 24. At 1142, the controller 50 detects again whether or not the printing paper 2 is present in the paper feed cassette 21, and thus whether or not the paper feed cassette is empty, by use of the sensor S1. If the paper feed cassette is empty, the operation returns to 1140; and if the paper feed cassette is not empty, the operation proceeds to 1144. At 1144, the controller 50 measures densities of magnetic flux generated from the permanent magnet P1 in three axes, respectively, by use of the 3D magnetic sensor S3 to calculate the magnet angle E, and stores the magnet angle E in the memory. Next, the operation proceeds to 1118.
At 1110, when the image forming apparatus 1 is used by the user, the controller 50 measures densities of magnetic flux generated from the permanent magnet P1 in three axes, respectively, by use of the 3D magnetic sensor S3, and calculates the magnet angle G from these measured values. At 1112, the controller 50 uses the factor K2, the magnet angle F and the magnet angle G to calculate a paper level in the paper feed cassette 21. The controller 50 can additionally display an indication on the UI40 so as to notify the user of the calculated paper level. At 1114, the controller 50 detects whether or not the printing paper 2 is present in the paper feed cassette 21, and thus whether or not the paper feed cassette is empty, by use of the sensor S1. If the paper feed cassette 21 is empty, the operation proceeds to 1116; and if the paper feed cassette 21 is not empty, the operation returns to 1110. At 1116, the controller 50 measures densities of magnetic flux generated from the permanent magnet P1 in three axes, respectively, by use of the 3D magnetic sensor S3 to calculate the magnet angle F, and stores magnet angle F in the memory. The controller 50 can update the magnet angle F stored in the memory with each measurement of the magnet angle F. At 1118, the controller 50 calculates the factor K2 as described above and stores the factor K2 in the memory. At 1120, the controller 50 measures a temperature around the permanent magnet P1 when the factor K2 is calculated, and stores the factor K2 as a temperature T2 in the memory. Next, the operation returns to 1104.
As described in the present disclosure, a combined use of a 3D magnetic sensor and a magnetic force generation element (for example, a permanent magnet) enables a position of, for example, the magnetic force generation element to be three-dimensionally determined by the 3D magnetic sensor. When a position of a magnetic force generation element is detected by use of a magnetic sensor that measures a density of magnetic flux in a single axis, the magnetic sensor may have to be disposed to face the magnetic force generation element. However, in examples described herein, the position of the magnetic force generation element can be three-dimensionally determined by the 3D magnetic sensor, to increase flexibility as to the position or location of the 3D magnetic sensor. For example, it is not necessary that the 3D magnetic sensor be mounted to face the magnetic force generation element. This can improve flexibility on the location where a sensor for detection should be attached, as well as to simplify the configuration to determine the position of the magnetic force generation element.
It is to be understood that not all aspects, advantages and features described herein may necessarily be achieved by, or included in, any one particular example. Indeed, having described and illustrated various examples herein, it should be apparent that other examples may be modified in arrangement and detail is omitted.
Number | Date | Country | Kind |
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2019-214855 | Nov 2019 | JP | national |
Filing Document | Filing Date | Country | Kind |
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PCT/US2020/055956 | 10/16/2020 | WO |