Patent ID: 12259239

DETAILED DESCRIPTION

The technical contents of this disclosure will become apparent with the detailed description of embodiments accompanied with the illustration of related drawings as follows. It is intended that the embodiments and drawings disclosed herein are to be considered illustrative rather than restrictive.

FIG.1is a schematic diagram of a sheet detection device1incorporated with a sheet tray9in the first embodiment of the disclosure.FIG.2is a schematic diagram of the sheet detection device1in the first embodiment of the disclosure.FIG.3AandFIG.3Bare the schematic diagrams of usage statuses of the sheet detection device1in the first embodiment of the disclosure.

Referring toFIG.1,FIG.2, andFIG.3A, the sheet detection device1of the embodiment may be, for example, disposed to be incorporated with the sheet tray9of a printer (not shown in figures). The sheet tray9may include a sheet guide91. The sheet guide91is disposed in the sheet tray9and capable of moving along a moving direction D. It should be noted that the sheet guide91may be a single side (such as left side, right side or bottom side) sheet guide (as shown inFIG.1), left side and right side linked sheet guide (as shown inFIG.4below), or left side (or right side) and bottom side linked sheet guide (not shown in figures), or the other sheet guides of linked or non-linked in different manners, here is not intended to be limiting. The aforementioned left side, right side or bottom side are described with respect to the side of the sheet tray9connected to the sheet inlet of the printer as the upper side.

The sheet detection device1of the embodiment includes a magnetic sensing element11, a first magnetic element12, a second magnetic element13, and a processing element14.

The magnetic sensing element11is disposed on the sheet guide91. The magnetic sensing element11may be, for example, a Hall sensor, here is not intended to be limiting. When the sheet guide91moves along the moving direction D, the sheet guide is configured to bring the magnetic sensing element11to move to a first position P1or a second position P2. The first position P1and the second position P2are set with respect to the sheet size to be detected. That is, when the magnetic sensing element11is adjacent to the first position P1and the second position P2, the sheet guide91abuts against the sheets with different sizes, respectively.

The first magnetic element12is disposed on the sheet tray9and corresponding to the first position P1. The first magnetic element12may be, for example, a magnet, and the magnetic intensity (or magnetic force) of the first magnetic element12is not limiting. For example, the magnetic intensity may be 3200 G, 2560 G, 1300 G, or other suitable magnetic intensity. Moreover, the arrangement of the direction of the magnetic moment (the direction from south pole S to north pole N of the magnet) of the first magnetic element12is not limiting. Here uses south pole S being disposed on the side adjacent to the magnetic sensing element11as an example.

The second magnetic element13is disposed on the sheet tray9and in spaced with the first magnetic element12, and is corresponding to the second position P2. The second magnetic element13may be, for example, a magnet, and the magnetic intensity (or magnetic force) of the second magnetic element13is not limiting. For example, the magnetic intensity may be 3200 G, 2560 G, 1300 G, or other suitable magnetic intensity. Similarly, the arrangement of the direction of the magnetic moment of the second magnetic element13is not limiting. Here uses south pole S being disposed on the side adjacent to the magnetic sensing element11as an example. It should be noted that the arrangement of the direction of the magnetic moment of the first magnetic element12and the second magnetic element13may be the same or different, here is not intended to be limiting. In some embodiments, the direction of the magnetic moment of the first magnetic element12and the direction of the magnetic moment of the second magnetic element13are parallel to each other, the magnetic moment direction of the first magnetic element12and the magnetic moment direction of the second magnetic element13are perpendicular to the moving direction D.

It is worth mentioning that the first magnetic element12and the second magnetic element13may the magnets of the same or different magnetic intensities.

In some embodiments, the first magnetic element12and the second magnetic element13may be located at the same side of the magnetic sensing element11(as shown inFIG.3A), located at two sides of the magnetic sensing element opposite to each other (as shown inFIG.4below), or located at the bottom side of the magnetic sensing element (not shown in figures, that is, the magnetic element is overlapped with the sheet guide91from top view), here is not intended to be limiting. The requirement is that the magnetic sensing element11is capable of generating the voltage signal correspondingly.

The processing element14is electrically connected with the magnetic sensing element11. The processing element14may include, for example, a sensor integrated circuit, a microcontroller unit (MCU), a microprocessor unit (MPU), a central processing unit (CPU), an application-specific integrated circuit (ASIC), a digital signal processor (DSP), a graphics processing unit (GPU), a field-programmable gate array (FPGA), or a system-on-chip (SoC), etc.

In some embodiments, the sheet detection device1may further include a storage element15. The storage element15is electrically connected with the processing element14, and configured to store a magnetic force-voltage lookup table T. The storage element15may be, for example, a nonvolatile storage medium, such as a read-only memory (ROM), an electrically-erasable programmable read-only memory (EEPROM), a flash memory (such as NAND flash or SSD with control chip, etc.), etc., here is not intended to be limiting.

Therefore, when the user moves the sheet guide91in the sheet tray9along the moving direction D to abut against the sheet, the magnetic sensing element11moves with the sheet guide91. When the magnetic sensing element11outputs the first voltage signal V1corresponding to the first magnetic element12, the processing element14is configured to determine that the sheet guide91is located at the first position P1according to the first voltage signal V1and the magnetic force-voltage lookup table T. Specifically, the formula of the magnetic sensing element11generating the first voltage signal V1(that is, Voutin the formula (1) below) corresponding to the first magnetic element12is as below.

Vout=VQ+B×(A⁢1Z⁢1)(1)B=Bt2⁢(D+ZR2+(D+Z)2-ZR2+Z2)(2)

VQis the lowest output voltage of the magnetic sensing element11.

A⁢1Z⁢1
is the magnetic sensitivity option of the magnetic sensing element11, for example, 200 mV/mT, here is not intended to be limiting. Btis remanence (referring to the data of physical magnet), which is irrelevant to the geometry of the first magnetic element12(for example, magnet). Z is the distance between pole faces on the symmetric axis. D is the thickness of the first magnetic element12. R is the radius of the first magnetic element12(for example, a round magnet). It is worth mentioning that the aforementioned calculation is, for example, being calculated and evaluated under the room temperature of 23° C., here is not intended to be limiting.

Moreover, when the sheet guide91is located at the first position P1, the magnetic sensing element11is adjacent to the first magnetic element12, the magnetic sensing element11and the first magnetic element12are distanced in a first distance Z1(that is, the parameter Z in the formula (2) above), and the magnetic sensing element11is configured to output the first voltage signal V1corresponding to the first distance Z1and the magnetic intensity of the first magnetic element12. It should be noted that the magnetic sensing element11being adjacent to the first magnetic element12indicates, for example, the center axis of the magnetic sensing element11and the center axis of the first magnetic element12being aligned with each other, or the center point of the magnetic sensing element11and the center point of the first magnetic element12being distanced in the shortest distance, or the other condition which the magnetic sensing element11is adjacent to the first magnetic element12and generates the first voltage signal V1, here is not intended to be limiting. Further, the first distance Z1is not limited to the condition which the magnetic sensing element11and the first magnetic element12are distanced in the shortest distance. The first distance Z1is the distance which the magnetic sensing element11is capable of generating the first voltage signal V1corresponding to the first magnetic element12.

Therefore, when the processing element14determines that the sheet guide91is located at the first position P1according to the first voltage signal V1and the magnetic force-voltage lookup table T, the processing element14is configured to output a first sheet size signal X1corresponding to the first position P1according to the first voltage signal V1.

Further, referring toFIG.3B, when the user moves the sheet guide91in the sheet tray9along the moving direction D to abut against the sheet, the magnetic sensing element11outputs the second voltage signal V2(that is, Voutin the formula (1) above) corresponding to the second magnetic element13, the processing element14is configured to determine that the sheet guide91is located at the second position P2according to the second voltage signal V2and the magnetic force-voltage lookup table T. It should be noted that the first voltage signal V1(as shown inFIG.3A) is different from the second voltage signal V2.

Specifically, when the sheet guide91is located at the second position P2, the magnetic sensing element11is adjacent to the second magnetic element13, the magnetic sensing element11and the second magnetic element13are distanced in a second distance Z2(that is, the parameter Z in the formula (2) above), and the magnetic sensing element11is configured to output the second voltage signal V2corresponding to the second distance Z2and the magnetic intensity of the second magnetic element13. It should be noted that the magnetic sensing element11being adjacent to the second magnetic element13indicates, for example, the center axis of the magnetic sensing element11and the center axis of the second magnetic element13being aligned with each other, or the center point of the magnetic sensing element11and the center point of the second magnetic element13being distanced in the shortest distance, or the other condition which the magnetic sensing element11is adjacent to the second magnetic element13and generates the second voltage signal V2, here is not intended to be limiting. Further, the second distance Z2is not limited to the condition which the magnetic sensing element11and the second magnetic element13are distanced in the shortest distance. The second distance Z2is the distance which the magnetic sensing element11is capable of generating the second voltage signal V2corresponding to the second magnetic element13.

Therefore, when the processing element14determines that the sheet guide91is located at the second position P2according to the second voltage signal V2, the processing element14is configured to output a second sheet size signal X2corresponding to the second position P2according to the second voltage signal V2.

It is worth mentioning that if the magnetic intensity of the first magnetic element12is different from the magnetic intensity of the second magnetic element13, the first distance Z1may be different from or the same with the second distance Z2. On the other hand, if the magnetic intensity of the first magnetic element12is the same with the magnetic intensity of the second magnetic element13, the first distance Z1is different from the second distance Z2.

Therefore, the sheet detection device1of the embodiment has the first magnetic element12and the second magnetic element13be disposed on the first position P1and the second position P2, and has the magnetic sensing element11generate the first voltage signal V1and the second voltage signal V2different with each other corresponding to the first magnetic element12and the second magnetic element13. As a result, when the sheet guide91brings the magnetic sensing element11to move to different positions, the magnetic sensing element11is configured to generate different voltage signals V1, V2corresponding to different magnetic elements12,13, and the processing element14is configured to precisely determine the position of the magnetic sensing element11. Comparing to the related art, which is solely structured by detecting “YES” or “NO” signal, the magnetic sensing element11of the sheet detection device1of the embodiment may still generate the corresponding voltage signals V1, V2when the position of the magnetic sensing element11is slightly deviated. Therefore, the erroneous signal determination may be avoided, and the size of the sheet abutted by the sheet guide91may be precisely determined.

FIG.4is a schematic diagram of the sheet detection device2in the second embodiment of the disclosure. The differences between the sheet detection device2of the embodiment and the sheet detection device1are that the sheet guide91is a left side and right side linked sheet guide, and the first magnetic element22and the second magnetic element23are located at two sides of the magnetic sensing element21opposite to each other.

It is worth mentioning that the arrangement of the direction of the magnetic moment of the first magnetic element22and the second magnetic element23is not limiting. Here uses south pole S being disposed on the side adjacent to the magnetic sensing element21as an example.

Similarly, when the sheet guide91is located at the first position P1, the magnetic sensing element21is adjacent to the first magnetic element22, and the magnetic sensing element21is configured to output the first voltage signal V1correspondingly. When the sheet guide91is located at the second position P2, the magnetic sensing element21is adjacent to the second magnetic element23, and the magnetic sensing element21is configured to output the second voltage signal V2correspondingly. Thus, the processing element14is configured to output the first sheet size signal X1or the second sheet size signal X2according to the first voltage signal V1or the second voltage signal V2, and the magnetic force-voltage lookup table T.

Therefore, comparing to the first magnetic element22and the second magnetic element23being disposed on the same side, the first magnetic element22and the second magnetic element23may be kept in a desirable distance in a manner of being disposed on two sides of the magnetic sensing element21opposite to each other. As a result, the condition of the magnetic sensing element21being simultaneously influenced by the first magnetic element22and the second magnetic element23, when the first magnetic element22and the second magnetic element23are not desirably distanced, may be avoided, and the sheet size being abutted by the sheet guide91may be determined more precisely.

FIG.5is a schematic diagram of the sheet detection device3in the third embodiment of the disclosure. The differences between the sheet detection device3of the embodiment and the aforementioned sheet detection device2are that the sheet detection device3has two magnetic sensing elements31A,31B, and the magnetic sensing elements31A,31B are disposed staggeredly on one component of the sheet guide91along the moving direction D. Further, the processing element14is electrically connected with the magnetic sensing elements31A,31B.

It is worth mentioning that “disposed staggeredly” indicates the central axes of the magnetic sensing elements31A,31B being staggered with a distance (for example, 10 mm). The magnetic sensing elements31A,31B may be non-coincided (or non-overlapped), or partly coincided (or overlapped). The distance of the magnetic sensing elements31A,31B being staggered is not limiting, the design may be different depending on different requirement. It should be noted that in the left side and right side linked sheet guide91, the magnetic sensing elements31A,31B may be disposed on different components of the sheet guide91.

Similarly, when the sheet guide91is located at the first position P1, the magnetic sensing element31A is adjacent to the first magnetic element32, and the magnetic sensing element31A is configured to output the first voltage signal V1correspondingly. When the sheet guide91is located at the second position P2, the magnetic sensing element31B is adjacent to the second magnetic element33, and the magnetic sensing element31B is configured to output the second voltage signal V2correspondingly. Thus, the processing element14is configured to output the first sheet size signal X1or the second sheet size signal X2according to the first voltage signal V1or the second voltage signal V2, and the magnetic force-voltage lookup table T.

Therefore, comparing to one magnetic sensing element, the distance between the first magnetic element32and the second magnetic element33on the moving direction D may be decreased by two magnetic sensing elements31A,31B being disposed staggeredly, and the whole structure of the sheet detection device3may be further compacted.

FIG.6is a schematic diagram of a sheet detection device4incorporated with a sheet tray9in the fourth embodiment of the disclosure.FIG.7is a schematic diagram of the sheet detection device4in the fourth embodiment of the disclosure.FIG.8AandFIG.8Bare the schematic diagrams of usage statuses of the sheet detection device4in the fourth embodiment of the disclosure.

Referring toFIG.6,FIG.7andFIG.8A, the difference between the sheet detection device4of the embodiment and the aforementioned sheet detection device3is that the sheet detection device4has the number of the magnetic elements42A,42B,42C,42D,42E,42F,42G corresponding to the number of the sheet size types to be detected. In the embodiment, the sheet detection device4is configured to have seven magnetic elements42A,42B,42C,42D,42E,42F,42G respectively corresponding to the sheet sizes of LT LEF (letter, long edge feed), LT SEF (letter, short edge feed), B5 SEF (B5, short edge feed), A3 SEF (A3, short edge feed), B4 SEF (B4, short edge feed), A4 SEF (A4, short edge feed), and A5 SEF (A5, short edge feed) as an example, here is not intended to be limiting. Further, here uses two magnetic sensing elements41A,41B as an example, here is not intended to be limiting, and more than two magnetic sensing elements may be disposed depending on different designs.

The magnetic element42A is disposed on the sheet tray9and corresponding to the position P1, and the position P1is corresponding to the sheet size LT LEF. The magnetic element42B is disposed on the sheet tray9and corresponding to the position P2, and the position P2is corresponding to the sheet size LT SEF. The magnetic element42C is disposed on the sheet tray9and corresponding to the position P3, and the position P3is corresponding to the sheet size B5 SEF. The magnetic element42D is disposed on the sheet tray9and corresponding to the position P4, and the position P4is corresponding to the sheet size A3 SEF. The magnetic element42E is disposed on the sheet tray9and corresponding to the position P5, and the position P5is corresponding to the sheet size B4 SEF. The magnetic element42F is disposed on the sheet tray9and corresponding to the position P6, and the position P6is corresponding to the sheet size A4 SEF. The magnetic element42G is disposed on the sheet tray9and corresponding to the position P7, and the position P7is corresponding to the sheet size A5 SEF. The magnetic elements42A,42B,42C,42D,42E,42F,42G may be, for example, a magnet.

The table 1 below, for example, is one embodiment of the magnetic force-voltage lookup table T. The magnetic force-voltage lookup table T includes the magnetic intensity (or magnetic force) of the magnetic elements42A,42B,42C,42D,42E,42F,42G, the distance Z (the distance that the magnetic sensing element is adjacent to the magnetic element, for example, the first distance Z1inFIG.8Aand the second distance Z2inFIG.8B) between the magnetic elements42A,42B,42C,42D,42E,42F,42G and the magnetic sensing elements41A,41B, the voltage data (including the voltage value Voutand the permissible range) generated by the magnetic sensing elements41A,41B correspondingly, and the sheet size data corresponding to the voltage data, here is not intended to be limiting.

TABLE 1MagneticDis-intensitytance(G)Z (mm)+10%Vout−10%Sheet size42A(P1)320023.623.343.07LT LEF/279 mm42B(P2)256022.732.542.34LT SEF/216 mm42C(P3)130012.061.931.79B5 SEF/182 mm42D(P4)256031.501.421.33A3 SEF/297 mm42E(P5)320041.361.291.22B4 SEF/257 mm42F(P6)256041.061.020.98A4 SFF/210 mm42G(P7)130020.990.960.92A5 SEF/148 mm

It is worth mentioning that the magnet may have ±10% of magnetic force variation during manufacturing. Thus, the voltage values Voutgenerated by the magnetic sensing elements41A,41B may have ±10% of permissible range.

Therefore, referring toFIG.8A, when the user moves the sheet guide91in the sheet tray9along the moving direction D to abut against the sheet, the magnetic sensing element41A moves with the sheet guide91. When the magnetic sensing element41A outputs the voltage signal V1corresponding to the magnetic element42A, the processing element14is configured to determine that the sheet guide91is located at the first position P1according to the table 1 (for example, the magnetic force-voltage lookup table T, which is stored in the storage element15electrically connected with the processing element14) and the voltage signal V1(for example, the range of 3.07 V-3.62 V corresponding to the voltage data of42A(P1) in the table 1). It should be noted that the magnetic sensing element41B may generate the voltage signal corresponding to another magnetic element at the same time, but the processing element14is configured to determine that the magnetic sensing element41B is not corresponding to any predetermined position according to the table 1.

Further, when the sheet guide91is located at the first position P1, the magnetic sensing element41A is adjacent to the magnetic element42A, the magnetic sensing element41A and the magnetic element42A are distanced in a distance Z1(that is, the parameter Z in the formula (2) above, for example, 2 mm in the table 1), and the magnetic sensing element41A is configured to output the voltage signal V1corresponding to the distance Z1and the magnetic intensity (for example, 3200 G in the table 1) of the magnetic element42A. It should be noted that the magnetic sensing element41A being adjacent to the magnetic element42A indicates, for example, the center axis of the magnetic sensing element41A and the center axis of the magnetic element42A being aligned with each other, or the center point of the magnetic sensing element41A and the center point of the magnetic element42A being distanced in the shortest distance, or the other condition which the magnetic sensing element41A is adjacent to the magnetic element42A and generates the voltage signal V1, here is not intended to be limiting. Further, the distance Z1is not limited to the condition which the magnetic sensing element41A and the magnetic element42A are distanced in the shortest distance. The distance Z1is the distance which the magnetic sensing element41A is capable of generating the voltage signal V1corresponding to the magnetic element42A.

Therefore, when the processing element14determines that the sheet guide91is located at the position P1according to the voltage signal V1, the processing element14is configured to determine the sheet size data (for example, indicating the sheet size LT LEF) corresponding to the voltage signal V1according to the table 1 to output the sheet size signal Xs corresponding to the position P1.

Moreover, referring toFIG.8B, when the user moves the sheet guide91in the sheet tray9along the moving direction D to abut against the sheet and the magnetic sensing element41B outputs the voltage signal V2corresponding to the magnetic element42D, the processing element14is configured to determine that the sheet guide91is located at the first position P4according to the table 1 and the voltage signal V2(for example, the range of 1.33 V-1.50 V corresponding to the voltage data of42D(P4) in the table 1). It should be noted that the magnetic sensing element41A may generate the voltage signal corresponding to another magnetic element at the same time, but the processing element14is configured to determine that the magnetic sensing element41A is not corresponding to any predetermined position according to the table 1.

Further, when the sheet guide91is located at the first position P4, the magnetic sensing element41B is adjacent to the magnetic element42D, the magnetic sensing element41B and the magnetic element42D are distanced in a distance Z2(that is, the parameter Z in the formula (2) above, for example, 3 mm in the table 1), and the magnetic sensing element41B is configured to output the voltage signal V2corresponding to the distance Z2and the magnetic intensity (for example, 2560 G in the table 1) of the magnetic element42D. It should be noted that the magnetic sensing element41B being adjacent to the magnetic element42D indicates, for example, the center axis of the magnetic sensing element41B and the center axis of the magnetic element42D being aligned with each other, or the center point of the magnetic sensing element41B and the center point of the magnetic element42D being distanced in the shortest distance, or the other condition which the magnetic sensing element41B is adjacent to the magnetic element42D and generates the voltage signal V2, here is not intended to be limiting. Further, the distance Z2is not limited to the condition which the magnetic sensing element41B and the magnetic element42D are distanced in the shortest distance. The distance Z2is the distance which the magnetic sensing element41B is capable of generating the voltage signal V2corresponding to the magnetic element42D.

Therefore, when the processing element14determines that the sheet guide91is located at the position P4according to the voltage signal V2, the processing element14is configured to determine the sheet size data (for example, indicating the sheet size A3 SEF) corresponding to the voltage signal V2according to the table 1 to output the sheet size signal Xs corresponding to the position P4.

It is worth mentioning that if the magnetic intensities of the magnetic elements42A,42B,42C,42D,42E,42F,42G are different from one another, the distances Z may be the same with or different from one another (for example, the magnetic elements42A,42B or the magnetic elements42A,42C in the table 1). On the other hand, if the magnetic intensity of the magnetic intensities of the magnetic elements42A,42B,42C,42D,42E,42F,42G are all the same, the distances Z are different from one another (for example, the magnetic elements42A,42E or the magnetic elements42B,42F in the table 1).

In summary, the sheet detection device4of the embodiment has the magnetic elements42A-42G be disposed on different position P1-P1, and has the magnetic sensing element41A,41B generate different voltage signals (such as the voltage signals V1, V2) corresponding to the magnetic elements42A-42G. As a result, when the sheet guide91brings the magnetic sensing elements41A,41B to move to different positions P1-P7, the magnetic sensing elements41A,41B are configured to generate different voltage signals corresponding to different magnetic elements42A-42G, and the processing element14is configured to precisely determine the position of the magnetic sensing elements41A,41B. Comparing to the related art, which is solely structured by detecting “YES” or “NO” signal, the magnetic sensing elements41A,41B of the sheet detection device4of the embodiment may still generate the corresponding voltage signals when the position of the magnetic sensing elements41A,41B are slightly deviated. Therefore, the erroneous signal determination may be avoided, and the size of the sheet abutted by the sheet guide91may be precisely determined.

Moreover, the magnetic elements42A-42G may be kept in a desirable distance in a manner of being disposed on two sides of the magnetic sensing elements41A,41B opposite to each other. As a result, the condition of the magnetic sensing elements41A,41B being simultaneously influenced by the magnetic elements42A-42G, when the magnetic elements42A-42G are not desirably distanced, may be avoided, and the sheet size being abutted by the sheet guide91may be determined more precisely.

Further, the distance between the magnetic elements42A-42G on the moving direction D may be decreased by two magnetic sensing elements41A,41B being disposed staggeredly, and the whole structure of the sheet detection device4may be further compacted.

The selecting manner of the magnetic force-voltage lookup table T in the aforementioned fourth embodiment is described as below, here is not intended to be limiting. In some embodiments, the magnetic force-voltage lookup table Ttotalwith the magnetic elements of magnetic intensities in 3200 G, 2560 G, and 1300 G are shown as below, here is not intended to be limiting. The magnetic force-voltage lookup table Ttotalmay include different parameters corresponding to different magnetic elements being selected.

Magnetic force-voltage lookup table TtotalDistanceMagnetic intensity(mm)(3200 G)Voltage signalZ+10%B−10%+10%Vout−10%1452.82411.65370.499.668.838.012150.93137.21123.493.623.343.07368.9162.6556.381.981.851.73437.7734.3430.901.361.291.22523.1821.0718.961.061.020.98615.3413.9512.550.910.880.85710.739.758.780.810.800.7887.827.116.400.760.740.7395.895.354.820.720.710.70104.554.133.720.690.680.671340.14309.22278.307.406.786.172106.6196.9287.222.732.542.34344.9140.8336.751.501.421.33422.8820.8018.721.061.020.97513.1911.9910.790.860.840.8268.287.536.780.770.750.7475.545.044.530.710.700.6983.893.533.180.680.670.6692.832.572.310.660.650.65102.121.931.740.640.640.63173.0166.3859.742.061.931.79219.5317.7615.980.990.960.9238.347.586.820.770.750.7444.424.023.620.690.680.6752.662.412.170.650.650.6461.731.571.420.630.630.6371.201.090.980.620.620.6280.860.790.710.620.620.6190.650.590.530.610.610.61100.500.450.410.610.610.61

Specifically, the unusable voltage signals are excluded based on the conditions of repeatedly output voltage signal, the magnet types under short distance, the corresponding sheet size, etc., and the suitable magnetic elements and the arranged positions are selected. Taking the fourth embodiment inFIG.8Aas an example, under the condition of the magnet element with magnetic force of 3200 G being distanced with the magnetic sensing element in a distance Z of 2 mm, the voltage value Voutgenerated by the magnetic sensing element is 3.34 V. The value is unique in the magnetic force-voltage lookup table Ttotal, and the same voltage signal is not generated in the other conditions. Therefore, the first magnetic element (for example, the magnetic element with magnetic force of 3200 G) may be disposed on the first position (for example, the position P1corresponding to LT LEF). Similarly, the second magnetic element (for example, the magnetic element with magnetic force of 2560 G) may be disposed on the second position (for example, the position P2corresponding to LT SEF).

It is worth mentioning that when the magnetic intensity of the first magnetic element and the magnetic intensity of the second magnetic element are the same, the second distance may be set to be different from the first distance according to the magnetic force-voltage lookup table Ttotal. Taking the fourth embodiment inFIG.8Aas an example, different magnetic elements42A,42E may be selected and different distances Z are set corresponding to different voltage signals.

Therefore, after the voltage signals from the magnetic sensing elements at different positions are tested to be consistent with the requirement of the magnetic force-voltage lookup table T, the arrangement of the sheet detection device of the disclosure is completed.

FIG.9is a flowchart of a detection method of the sheet detection device of the disclosure. As shown inFIG.9, the detection method of the sheet detection device of the disclosure includes the step S10to the step S13. The step S10is disposing a magnetic sensing element on the sheet guide, disposing a first magnetic element on the sheet tray, and storing a magnetic force-voltage lookup table in the storage element. The step S11is when the sheet guide moves along the moving direction, generating a first voltage signal, by the magnetic sensing element disposed on the sheet guide, corresponding to the first magnetic element disposed on the sheet tray. The step S12is receiving the first voltage signal by the processing element. The step S13is determining, by the processing element, that the sheet guide is located at a first position according to the first voltage signal and the magnetic force-voltage lookup table.

In some embodiments, the magnetic force-voltage lookup table includes a first voltage data and a first sheet size data corresponding to the first voltage data. In the step S13, the determining, by the processing element, of the sheet guide being located at the first position further includes: when the processing element determines that the first voltage signal is corresponding to the first voltage data, the processing element is configured to output a first sheet size signal corresponding to the first position according to the first sheet size data.

It worth mentioning that the detection method of the embodiment may be applied to different sheet detection device. For example, the detection method of the embodiment may be applied to the sheet detection devices1-4in the first embodiment to the fourth embodiment, and here is omitted for brevity.

FIG.10is another flowchart of a detection method of the sheet detection device of the disclosure. The detection method of the sheet detection device of the disclosure further includes the step S14to the step S17. The step S14is disposing a second magnetic element on the sheet tray. The step S15is generating a second voltage signal, by the magnetic sensing element, corresponding to the second magnetic element disposed on the sheet tray. The step S16is receiving the second voltage signal by the processing element. The step S17is determining, by the processing element, that the sheet guide is located at a second position according to the second voltage signal and the magnetic force-voltage lookup table.

In some embodiments, in the step S17, the determining, by the processing element, of the sheet guide being located at the second position further includes: outputting a second sheet size signal, by the processing element, corresponding to the second position according to the second voltage signal.

It worth mentioning that the detection method of the embodiment may be applied to different sheet detection device. For example, the detection method of the embodiment may be applied to the sheet detection devices1-4in the first embodiment to the fourth embodiment, and here is omitted for brevity.

In summary, the sheet detection device and the detection method thereof the disclosure has the magnetic elements be disposed on different positions, and has the magnetic sensing elements generate different voltage signals corresponding to the magnetic elements. As a result, when the sheet guide brings the magnetic sensing element to move to different positions, the magnetic sensing element is configured to generate different voltage signals corresponding to different magnetic elements, and the processing element is configured to precisely determine the position of the magnetic sensing element. Comparing to the related art, which is solely structured by detecting “YES” or “NO” signal, the magnetic sensing element of the sheet detection device of the disclosure may still generate the corresponding voltage signal when the position of the magnetic sensing element is slightly deviated. Therefore, the erroneous signal determination may be avoided, and the size of the sheet abutted by the sheet guide may be precisely determined.

Further, the magnetic elements may be kept in a desirable distance in a manner of being disposed on two sides of the magnetic sensing elements opposite to each other. As a result, the condition of the magnetic sensing elements being simultaneously influenced by the magnetic elements, when the magnetic elements are not desirably distanced, may be avoided, and the sheet size being abutted by the sheet guide may be determined more precisely.

Moreover, the distance between the magnetic elements on the moving direction may be decreased by the magnetic sensing elements being disposed staggeredly, and the whole structure of the sheet detection device may be further compacted.

While this disclosure has been described by means of specific embodiments, numerous modifications and variations may be made thereto by those skilled in the art without departing from the scope and spirit of this disclosure set forth in the claims.