JP2016114476A - Powder detector, developer residual quantity detector, and image formation device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To accurately detect a state in which the residual quantity of a developer in a vessel is small, and to prevent the developer in the vessel from scattering out of the vessel.SOLUTION: The powder detector for detecting the toner residual quantity in a sub hopper 200 includes: a vibration structure 210 that is disposed inside the sub hopper 200 and vibrates by an influence of toner; and a magnetic flux sensor 10 for detecting the vibration state of the vibration structure 210. They are arranged so as to face each other via a housing of the sub hopper 200, and the space including each of them is blocked in the facing direction.SELECTED DRAWING: Figure 29

Description

  The present invention relates to a powder detection device, a developer remaining amount detection device, and a powder detection method.

  In recent years, there has been a tendency to digitize information, and image processing apparatuses such as printers and facsimiles used for outputting digitized information and scanners used for digitizing documents have become indispensable devices. Among such image processing apparatuses, as an image formation output method, an electrophotographic method for performing image formation output by transferring an image formed by developing an electrostatic latent image formed on a photoreceptor onto a sheet. It has been known.

  In an electrophotographic image forming apparatus, a developer is supplied from a container that is a developer supply source to a developing device that develops an electrostatic latent image formed on a photoreceptor. As a method for detecting the remaining amount of the developer supplied in this way, for example, the member to be pressed is deformed by a member for stirring the developer, and the member to be detected accompanying the deformation of the member to be pressed is used. A method of referring to the change in the above has been proposed (see, for example, Patent Document 1).

  In the case of the method disclosed in Patent Document 1, the amount of toner in the container is not always reflected uniformly on the deformation of the pressed sheet. In addition, there are problems in detection accuracy, such as a change with time of the pressed sheet and adhesion of the developer to the pressed sheet.

  To solve such a problem, the vibration mode of the vibrating portion that is bounced and vibrates is changed according to the remaining amount of toner, and the remaining amount of toner is detected by detecting the vibration mode of the vibrating portion. Can be considered. According to such an aspect, since a delicate event called vibration of the vibration unit is set as a detection target, a change in state due to the remaining amount of toner can be clearly detected. As a result, the remaining amount of the developer in the container can be detected with high accuracy.

  In the case of using such a vibration part or a sensor for detecting the vibration part (hereinafter, generally referred to as “detection member”), it is necessary to appropriately attach them to the container. For example, as a mode of attaching these detection members to the container, a method of fixing them through a through hole provided in the container and the detection member with a screw or the like is conceivable.

  However, when a through hole is provided in the container, the toner scatters out of the container through the through hole, causing problems such as dirt inside and outside the apparatus and malfunction due to toner depositing on the mechanical configuration. is there.

  The present invention has been made in view of the above circumstances, and detects the state in which the remaining amount of the developer in the container is low with high accuracy, and the developer in the container is scattered outside the container. The purpose is to prevent this.

  In order to solve the above-described problem, one aspect of the present invention is a powder detection device that detects the remaining amount of powder having fluidity in a container, the powder detection apparatus being disposed inside the container, Based on the detection result of the vibration part that vibrates under the influence of the body, the vibration detection part that detects the vibration state of the vibration part, the vibration applying part that vibrates the vibration part, and the vibration detection part A detection processing unit that detects a remaining amount of powder, and the vibration unit and the vibration detection unit are disposed to face each other via a casing of the container, and the space in which the vibration unit is disposed and the The space where the vibration detection unit is arranged is characterized in that the vibration unit and the vibration detection unit are blocked in a facing direction.

  According to the present invention, it is possible to detect with high accuracy the state in which the remaining amount of the developer in the container is low, and to prevent the developer in the container from scattering outside the container.

1 is a diagram illustrating a mechanical configuration of an image forming apparatus including a developing device on which a magnetic flux sensor according to an embodiment of the present invention is mounted. FIG. 3 is a perspective view illustrating a toner supply configuration according to an exemplary embodiment of the present invention. It is a perspective view which shows the general appearance of the sub hopper which concerns on embodiment of this invention. It is a perspective view which shows the general appearance of the sub hopper which concerns on embodiment of this invention. It is a figure which shows the circuit structure of the magnetic flux sensor which concerns on embodiment of this invention. It is a figure which shows the count aspect of the output signal of the magnetic flux sensor which concerns on embodiment of this invention. 1 is a perspective view showing an overview of a magnetic flux sensor according to an embodiment of the present invention. It is a block diagram which shows the structure of the controller which acquires the signal of the magnetic flux sensor which concerns on embodiment of this invention. It is a figure which shows the arrangement | positioning relationship between the magnetic flux sensor which concerns on embodiment of this invention, and a diaphragm. It is a figure which shows the effect | action at the time of a magnetic flux passing the diaphragm which concerns on embodiment of this invention. It is a figure which shows the oscillation frequency of the magnetic flux sensor according to the distance of the diaphragm which concerns on embodiment of this invention, and a magnetic flux sensor. It is a perspective view which shows the arrangement | positioning state of the diaphragm which concerns on embodiment of this invention. It is a side view which shows the arrangement | positioning relationship between the diaphragm which concerns on embodiment of this invention, and a stirring member. It is a side view which shows the arrangement | positioning relationship between the diaphragm which concerns on embodiment of this invention, and a stirring member. It is a top view which shows the arrangement | positioning relationship between the diaphragm which concerns on embodiment of this invention, and a stirring member. It is a side view which shows the arrangement | positioning relationship between the diaphragm which concerns on embodiment of this invention, and a stirring member. It is a top view which shows the vibration state of the diaphragm which concerns on embodiment of this invention. It is a side view which shows the relationship between the vibration state of the diaphragm which concerns on embodiment of this invention, and a color developer. It is a figure which shows a time-dependent change of the count value according to the oscillation frequency of the magnetic flux sensor which changes according to attenuation | damping of the vibration of the diaphragm which concerns on embodiment of this invention. 7 is a flowchart illustrating a toner remaining amount detection operation according to the embodiment of the present invention. It is a figure which shows the analysis aspect of the count value which concerns on embodiment of this invention. It is a figure which shows the relationship between the sampling period of the count value which concerns on embodiment of this invention, and the vibration period of a diaphragm. It is a figure which shows the space | interval of the magnetic flux sensor which concerns on embodiment of this invention, and a diaphragm. It is a figure which shows the example of arrangement | positioning height of the magnetic flux sensor which concerns on embodiment of this invention, and a diaphragm. It is a figure which shows the example of arrangement | positioning height of the magnetic flux sensor which concerns on embodiment of this invention, and a diaphragm. It is a figure which shows the example in the case of employ | adopting the magnetic flux sensor and diaphragm which concern on embodiment of this invention for a developing device. It is a side view which shows the other example of the coil which concerns on embodiment of this invention. It is a front view which shows the other example of the coil which concerns on embodiment of this invention. It is a figure which shows the arrangement | positioning aspect of the detection member which concerns on embodiment of this invention. It is a figure which shows the arrangement | positioning aspect of the detection member which concerns on embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In this embodiment, in an electrophotographic image forming apparatus, toner is supplied between a developing unit that develops an electrostatic latent image formed on a photoreceptor and a container that is a supply source of toner that is a developer. An example of detecting the remaining amount of toner in the sub hopper to be held will be described.

  FIG. 1 is a side view showing a mechanism for image forming output included in the image forming apparatus 100 according to the present embodiment. As shown in FIG. 1, the image forming apparatus 100 according to the present embodiment includes a configuration in which image forming units 106 </ b> K to 106 </ b> Y of respective colors are arranged along a conveyance belt 105 that is an endless moving unit. It is said to be a tandem type. That is, along the transport belt 105, which is an intermediate transfer belt on which an intermediate transfer image for transfer onto a sheet (an example of a recording medium) 104 that is separated and fed from the sheet feed tray 101 by the sheet feed roller 102 is formed. A plurality of image forming units (electrophotographic process units) 106Y, 106M, 106C, and 106K (hereinafter collectively referred to as image forming units 106) are arranged in order from the upstream side in the transport direction of the transport belt 105.

  Further, the sheet 104 fed from the sheet feeding tray 101 is stopped once by the registration roller 103 and is sent out to the image transfer position from the conveying belt 105 according to the image forming timing in the image forming unit 106.

  The plurality of image forming units 106Y, 106M, 106C, and 106K have the same internal configuration except that the colors of the toner images to be formed are different. The image forming unit 106K forms a black image, the image forming unit 106M forms a magenta image, the image forming unit 106C forms a cyan image, and the image forming unit 106Y forms a yellow image. In the following description, the image forming unit 106Y will be described in detail. However, since the other image forming units 106M, 106C, and 106K are the same as the image forming unit 106Y, the image forming units 106M, 106C, and 106K. For each of these components, instead of Y added to each component of the image forming unit 106Y, only the symbols distinguished by M, C, and K are displayed in the figure, and the description is omitted.

  The conveying belt 105 is an endless belt, that is, an endless belt that is stretched between a driving roller 107 and a driven roller 108 that are rotationally driven. The drive roller 107 is driven to rotate by a drive motor (not shown), and the drive motor, the drive roller 107, and the driven roller 108 function as a drive unit that moves the conveyance belt 105 that is an endless moving unit. .

  During image formation, the first image forming unit 106Y transfers a yellow toner image to the conveyance belt 105 that is driven to rotate. The image forming unit 106Y includes a photoconductor drum 109Y as a photoconductor, a charger 110Y disposed around the photoconductor drum 109Y, an optical writing device 111, a developing device 112Y, a photoconductor cleaner 113Y, and a static eliminator (not shown). ) Etc. The optical writing device 111 is configured to irradiate light to each of the photosensitive drums 109Y, 109M, 109C, and 109K (hereinafter collectively referred to as “photosensitive drum 109”).

  In the image formation, the outer peripheral surface of the photosensitive drum 109Y is uniformly charged by the charger 110Y in the dark, and then writing is performed by light from the light source corresponding to the yellow image from the optical writing device 111. An electrostatic latent image is formed. The developing device 112Y visualizes the electrostatic latent image with yellow toner, thereby forming a yellow toner image on the photosensitive drum 109Y.

  This toner image is transferred onto the conveyance belt 105 by the action of the transfer unit 115Y at a position (transfer position) where the photosensitive drum 109Y and the conveyance belt 105 come into contact or closest to each other. By this transfer, an image of yellow toner is formed on the conveyance belt 105. After the transfer of the toner image is completed, the photosensitive drum 109Y is wiped away with unnecessary toner remaining on the outer peripheral surface by the photosensitive member cleaner 113Y, and then is neutralized by the static eliminator, and waits for the next image formation.

  As described above, the yellow toner image transferred onto the conveying belt 105 by the image forming unit 106Y is conveyed to the next image forming unit 106M by driving the rollers of the conveying belt 105. In the image forming unit 106M, a magenta toner image is formed on the photosensitive drum 109M by the same process as the image forming process in the image forming unit 106Y, and the toner image is superimposed and transferred onto the already formed yellow image. Is done.

  The yellow and magenta toner images transferred onto the conveying belt 105 are further conveyed to the next image forming units 106C and 106K, and the cyan toner image formed on the photosensitive drum 109C and the photosensitive member are subjected to the same operation. The black toner image formed on the body drum 109K is superimposed and transferred on the already transferred image. Thus, a full-color intermediate transfer image is formed on the conveyance belt 105.

  The sheets 104 stored in the sheet feed tray 101 are sent out in order from the top, and the intermediate transfer image formed on the conveyance belt 105 is transferred at a position where the conveyance path is in contact with or closest to the conveyance belt 105. It is transferred onto the paper. As a result, an image is formed on the surface of the sheet 104. The sheet 104 on which the image is formed on the sheet surface is further conveyed, the image is fixed by the fixing device 116, and then discharged to the outside of the image forming apparatus.

  A belt cleaner 118 is provided for the conveyor belt 105. As shown in FIG. 1, the belt cleaner 118 is a cleaning blade pressed against the conveyance belt 105 on the downstream side of the transfer position of the image from the conveyance belt 105 to the paper 104 and upstream of the photosensitive drum 109. And a developer remover that scrapes off toner adhering to the surface of the conveyor belt 105.

  Next, a configuration for supplying toner to the developing device 112 will be described with reference to FIG. The toner supply configuration is generally the same for each color of CMYK, and FIG. 2 shows the supply configuration for one developing device 112. The toner is contained in the toner bottle 117, and as shown in FIG. 2, the toner is supplied from the toner bottle 117 to the sub hopper 200 via the toner bottle supply path 120.

  The sub hopper 200 temporarily holds the toner supplied from the toner bottle 117 and supplies the toner to the developing device 112 according to the remaining amount of toner in the developing device 112. Toner is supplied from the sub hopper 200 to the developing device 112 via the sub hopper supply path 119. The gist of the present embodiment is to detect a state in which the toner in the toner bottle 117 runs out and toner is not supplied to the sub hopper 200 and the amount of toner in the sub hopper 200 is reduced.

  FIG. 3 is a perspective view showing an overview of the sub hopper 200 according to the present embodiment. As shown in FIG. 3, the magnetic flux sensor 10 is attached to the outer wall of the casing constituting the sub hopper 200. In FIG. 3, the upper portion of the sub hopper 200 is an opening, and a cover in which the toner bottle supply path 120 is formed is attached to the opening. The toner held in the sub hopper 200 is sent out from the sub hopper supply path 119 shown in FIG.

  FIG. 4 is a perspective view showing the inside of the sub hopper 200. As shown in FIG. 4, a diaphragm 201 is provided on the inner wall inside the sub hopper 200. The inner wall provided with the diaphragm 201 is the back side of the outer wall to which the magnetic flux sensor 10 is attached in FIG. Therefore, the diaphragm 201 is disposed so as to face the magnetic flux sensor 10.

  The vibration plate 201 is a rectangular plate-shaped component, and is arranged in a cantilever state in which one end in the longitudinal direction is fixed to the housing of the sub hopper 200. A weight 202 is disposed at the end of the diaphragm 201 that is not fixed in the longitudinal direction. The weight 202 has a function of adjusting the frequency when the vibration plate 201 vibrates and a function of vibrating the vibration plate 201.

  In the sub hopper 200, a rotating shaft 204 and a stirring member 205 are provided as a configuration for stirring the toner inside. The rotating shaft 204 is a shaft that rotates inside the sub hopper 200. An agitating member 205 is fixed to the rotating shaft 204, and the agitating member 205 rotates with the rotation of the rotating shaft 204 to agitate the toner in the sub hopper 200. Further, the longitudinal direction of the diaphragm 201 is disposed substantially parallel to the axial direction of the rotating shaft 204.

  The stirring member 205 has a function of flipping the weight 202 provided on the vibration plate 201 by rotation in addition to the stirring of the toner. Thus, each time the stirring member 205 rotates once, the weight 202 is repelled and the diaphragm 201 vibrates. That is, the vibration plate 201 functions as a vibration unit, and the stirring member 205 functions as a vibration applying unit. The gist of the present embodiment is to detect the remaining amount of toner in the sub hopper 200 by detecting the vibration of the vibration plate 201.

  Next, the internal configuration of the magnetic flux sensor 10 according to the present embodiment will be described with reference to FIG. As shown in FIG. 5, the magnetic flux sensor 10 according to the present embodiment is an oscillation circuit based on a Colpitts type LC oscillation circuit, and includes a planar pattern coil 11, a pattern resistor 12, a first capacitor 13, and a second capacitor 14. , Feedback resistor 15, unbuffered ICs 16 and 17, and output terminal 18.

  The planar pattern coil 11 is a planar coil constituted by signal lines patterned in a planar shape on a substrate constituting the magnetic flux sensor 10. As shown in FIG. 5, the planar pattern coil 11 has an inductance L obtained by the coil. In the planar pattern coil 11, the value of the inductance L changes due to the magnetic flux passing through the space facing the plane on which the coil is formed. As a result, the magnetic flux sensor 10 according to the present embodiment is used as an oscillating unit that oscillates a signal having a frequency corresponding to the magnetic flux passing through the space where the coil surfaces of the planar pattern coil 11 face each other.

The pattern resistor 12 is a resistor configured by a signal line patterned in a planar shape on a substrate, like the planar pattern coil 11. The pattern resistor 12 according to the present embodiment is a pattern formed in a zigzag shape, thereby creating a state in which current does not flow more easily than a linear pattern. Providing this pattern resistor 12 is one of the gist according to the present embodiment. In other words, the zigzag folded shape is a shape folded so as to reciprocate a plurality of times in a predetermined direction. As shown in FIG. 5, it is patterned resistor 12 has a resistance value _{R P.} As shown in FIG. 5, the planar pattern coil 11 and the pattern resistor 12 are connected in series.

  The first capacitor 13 and the second capacitor 14 are capacitors that together with the planar pattern coil 11 constitute a Colpitts LC oscillation circuit. Therefore, the first capacitor 13 and the second capacitor 14 are connected in series with the planar pattern coil 11 and the pattern resistor 12. A resonance current loop is constituted by a loop constituted by the planar pattern coil 11, the pattern resistor 12, the first capacitor 13 and the second capacitor 14.

  The feedback resistor 15 is inserted to stabilize the bias voltage. Due to the functions of the unbuffered IC 16 and the unbuffered IC 17, the potential fluctuation of a part of the resonant current loop is output from the output terminal 18 as a rectangular wave corresponding to the resonant frequency.

With such a configuration, the magnetic flux sensor 10 according to the present embodiment oscillates at a frequency f corresponding to the inductance L, the resistance value R _P , and the capacitance C of the first capacitor 13 and the second capacitor 14. The frequency f can be expressed by the following formula (1).

  The inductance L also changes depending on the presence of the magnetic substance in the vicinity of the planar pattern coil 11 and its concentration. Therefore, the magnetic permeability in the space near the planar pattern coil 11 can be determined from the oscillation frequency of the magnetic flux sensor 10.

  Further, as described above, the magnetic flux sensor 10 in the sub hopper 200 according to the present embodiment is disposed to face the diaphragm 201 via the housing. Accordingly, the magnetic flux generated by the planar pattern coil 11 passes through the diaphragm 201. That is, the diaphragm 201 affects the magnetic flux generated by the planar pattern coil 11 and affects the inductance L. As a result, the presence of the diaphragm 201 affects the frequency of the oscillation signal of the magnetic flux sensor 10. This is one of the gist according to the present embodiment. Details will be described later.

FIG. 6 is a diagram illustrating an aspect of the count value of the output signal of the magnetic flux sensor 10 according to the present embodiment. If there is no change in the magnetic flux generated by the planar pattern coil 11 included in the magnetic flux sensor 10, the magnetic flux sensor 10 continues to oscillate at the same frequency in principle. As a result, as shown in FIG. 6, the count value of the counter uniformly increases with the passage of time, and as shown in FIG. 6, the timing of each of t ₁ , t ₂ , t ₃ , t ₄ , t _5. , Count values such as aaaah, bbbbbh, cccch, ddddh, AAAAh are acquired.

By calculating the count value at each timing based on the periods T ₁ , T ₂ , T ₃ , and T ₄ shown in FIG. 6, the frequency in each period is calculated. For example, when a frequency is calculated by outputting an interrupt signal when a reference clock corresponding to 2 (msec) is counted, T ₁ and T shown in FIG. 6 are obtained by dividing the count value in each period by 2 (msec). The oscillation frequency f (Hz) of the magnetic flux sensor 10 in each of the periods T ₂ , T ₃ and T ₄ is calculated.

Further, as shown in FIG. 6, when the upper limit of the count value of the counter is FFFFh, when calculating the frequency in the period _{T 4,} a value obtained by subtracting ddddh from FFFFh, the sum of the values of the AAAAh 2 (msec ), The oscillation frequency f (Hz) can be calculated.

  As described above, in the image forming apparatus 100 according to the present embodiment, the frequency of the signal oscillated by the magnetic flux sensor 10 is acquired, and an event corresponding to the oscillation frequency of the magnetic flux sensor 10 can be determined based on the acquisition result. it can. In the magnetic flux sensor 10 according to the present embodiment, the inductance L changes according to the state of the diaphragm 201 arranged facing the planar pattern coil 11, and as a result, the signal output from the output terminal 18 is changed. The frequency changes.

  As a result, in the controller that acquires the signal, it is possible to check the state of the diaphragm 201 that is disposed to face the planar pattern coil 11. Judging the state of the developer inside the sub hopper 200 based on the state of the diaphragm 201 confirmed in this way is one of the gist according to the present embodiment.

  As described above, the frequency is obtained by dividing the count value of the oscillation signal by the period. If the period for acquiring the count value is fixed, the acquired count value is used as a parameter for indicating the frequency. It is also possible to use it as it is.

  FIG. 7 is a perspective view showing an overview of the magnetic flux sensor 10 according to the present embodiment. In FIG. 7, the surface on which the planar pattern coil 11 and the pattern resistor 12 described in FIG. 5 are formed, that is, the detection surface facing the space where the magnetic permeability is to be detected is directed to the upper surface.

  As shown in FIG. 7, the pattern resistor 12 connected in series with the planar pattern coil 11 is patterned on the detection surface on which the planar pattern coil 11 is formed. As described with reference to FIG. 5, the planar pattern coil 11 is a signal line pattern formed in a spiral shape on a plane. Further, the pattern resistor 12 is a signal pattern formed in a zigzag pattern on the plane, and the function of the magnetic flux sensor 10 as described above is realized by these patterns.

  A portion formed by the planar pattern coil 11 and the pattern resistor 12 is a magnetic permeability detecting unit in the magnetic flux sensor 10 according to the present embodiment. When the magnetic flux sensor 10 is attached to the sub hopper 200, the detector is attached so as to face the diaphragm 201.

  Next, a configuration for acquiring the output value of the magnetic flux sensor 10 in the image forming apparatus 100 according to the present embodiment will be described with reference to FIG. FIG. 8 is a diagram illustrating the configuration of the controller 20 and the magnetic flux sensor 10 that acquire the output value of the magnetic flux sensor 10. As shown in FIG. 8, the controller 20 according to the present embodiment includes a CPU (Central Processing Unit) 21, an ASIC (Application Specific Integrated Circuit) 22, a timer 23, a crystal oscillation circuit 24, and an input / output control ASIC 30.

  The CPU 21 is a calculation means, and controls the entire operation of the controller 20 by performing calculations according to a program stored in a storage medium such as a ROM (Read Only Memory). The ASIC 22 functions as a connection interface between the system bus to which the CPU 21 and RAM (Random Access Memory) are connected and other devices.

  The timer 23 generates an interrupt signal and outputs it to the CPU 21 every time the count value of the reference clock input from the crystal oscillation circuit 24 reaches a predetermined value. In response to the interrupt signal input from the timer 23, the CPU 21 outputs a read signal for acquiring the output value of the magnetic flux sensor 10. The crystal oscillation circuit 24 oscillates a reference clock for operating each device in the controller 20.

  The input / output control ASIC 30 acquires a detection signal output from the magnetic flux sensor 10 and converts it into information that can be processed in the controller 20. As shown in FIG. 8, the input / output control ASIC 30 includes a magnetic permeability counter 31, a read signal acquisition unit 32, and a count value output unit 33. As described above, the magnetic flux sensor 10 according to the present embodiment is an oscillation circuit that outputs a rectangular wave having a frequency corresponding to the magnetic permeability in the detection target space.

  The permeability counter 31 is a counter that increments a value in accordance with a rectangular wave output from such a magnetic flux sensor 10. That is, the magnetic permeability counter 31 functions as a target signal counter that counts the number of signals for which the frequency is to be calculated. Note that the magnetic flux sensor 10 according to the present embodiment is provided for each of the sub hoppers 200 connected to the CMYK color developing devices 112, and a plurality of magnetic permeability counters 31 are provided accordingly.

  The read signal acquisition unit 32 acquires a read signal, which is a command for acquiring the count value of the magnetic permeability counter 31 from the CPU 21, via the ASIC 22. When the read signal acquisition unit 32 acquires the read signal from the CPU 21, the read signal acquisition unit 32 inputs a signal for causing the count value output unit 33 to output the count value. The count value output unit 33 outputs the count value of the magnetic permeability counter 31 in accordance with the signal from the read signal acquisition unit 32.

  Note that the CPU 21 accesses the input / output control ASIC 30 via, for example, a register. For this reason, the above-described read signal is performed by the CPU 21 writing a value in a predetermined register included in the input / output control ASIC 30. The count value is output by the count value output unit 33 when the count value is stored in a predetermined register included in the input / output control ASIC 30 and the CPU 21 acquires the value. The controller 20 shown in FIG. 8 may be provided separately from the magnetic flux sensor 10 or may be mounted on the substrate of the magnetic flux sensor 10 as a circuit including the CPU 21.

  In such a configuration, the CPU 21 detects the vibration state of the diaphragm 201 based on the count value acquired from the count value output unit 33, and detects the toner remaining amount in the sub hopper 200 based on the detection result. In other words, the detection processing unit is configured by the CPU 21 performing calculations according to a predetermined program. Further, the count value acquired from the count value output unit 33 is used as frequency-related information indicating the frequency of the magnetic flux sensor 10 that changes according to the vibration of the diaphragm 201.

  Next, the influence of the diaphragm 201 on the oscillation frequency of the magnetic flux sensor 10 according to the present embodiment will be described. As shown in FIG. 9, the surface on which the planar pattern coil 11 is formed in the magnetic flux sensor 10 and the diaphragm 201 are disposed to face each other with the housing of the sub hopper 200 interposed therebetween. Then, as shown in FIG. 9, a magnetic flux is generated around the center of the planar pattern coil 11, and the magnetic flux penetrates the diaphragm 201.

Diaphragm 201, for example SUS is constituted by plates, the magnetic flux G ₁ as shown in FIG. 10 eddy current is generated in the vibrating plate 201 by penetrating the vibrating plate 201. This eddy current generates a magnetic flux G _2, acts so as to cancel out the magnetic fluxes G ₁ by a plane pattern coil 11. Thus, by canceling out the magnetic flux G1, the inductance L in the magnetic flux sensor 10 decreases. As shown in the above equation (1), when the inductance L decreases, the oscillation frequency f increases.

  The strength of the eddy current generated inside the diaphragm 201 by receiving the magnetic flux from the planar pattern coil 11 varies depending on the distance between the planar pattern coil 11 and the diaphragm 201 in addition to the strength of the magnetic flux. FIG. 11 is a diagram illustrating the oscillation frequency of the magnetic flux sensor 10 in accordance with the distance between the planar pattern coil 11 and the diaphragm 201.

  The strength of the eddy current generated inside the diaphragm 201 is inversely proportional to the distance between the planar pattern coil 11 and the diaphragm 201. Therefore, as shown in FIG. 11, the narrower the distance between the planar pattern coil 11 and the diaphragm 201, the higher the oscillation frequency of the magnetic flux sensor 10, and when it becomes narrower than the predetermined distance, the inductance L becomes too low and oscillation occurs. No longer.

  In the sub hopper 200 according to the present embodiment, the vibration of the diaphragm 201 is detected based on the oscillation frequency of the magnetic flux sensor 10 by utilizing the characteristics as shown in FIG. The gist of the present embodiment is to detect the remaining amount of toner in the sub hopper 200 based on the vibration of the vibration plate 201 thus detected. That is, the diaphragm 201 and the magnetic flux sensor 10 shown in FIG. 9 and the configuration for processing the output signal of the magnetic flux sensor 10 are used as the powder detection device according to the present embodiment. This powder detection device is a developer remaining amount detection device if used for detection of the remaining amount of toner. Further, the magnetic flux sensor 10 functions as a vibration detection unit.

  The vibration of the diaphragm 201 repelled by the stirring member 205 is represented by a natural frequency determined by the rigidity of the diaphragm 201 and the weight of the weight 202 and an attenuation factor determined by an external factor that absorbs the vibration energy. As external factors that absorb vibration energy, in addition to fixing factors such as fixing strength and air resistance for fixing the vibration plate 201 in a cantilever state, toner that contacts the vibration plate 201 inside the sub hopper 200 is used. There is a presence.

  The toner that contacts the vibration plate 201 inside the sub hopper 200 varies depending on the remaining amount of toner in the sub hopper 200. Therefore, by detecting the vibration of the vibration plate 201, it is possible to detect the remaining amount of toner in the sub hopper 200. Therefore, in the sub hopper 200 according to the present embodiment, the stirring member 205 for stirring the toner in the inside repels the vibration plate 201 and periodically vibrates the vibration plate 201 according to the rotation.

  Next, the arrangement of components around the diaphragm 201 in the sub hopper 200 and the configuration for the stirring member 205 to flip the diaphragm 201 will be described. FIG. 12 is a perspective view showing the positional relationship around the diaphragm 201. As shown in FIG. 12, the diaphragm 201 is fixed to the housing of the sub hopper 200 via a fixing portion 201a.

  FIG. 13 is a side view showing a state before the stirring member 205 comes into contact with the weight 202 attached to the diaphragm 201 as the rotation state of the rotating shaft 204. In FIG. 13, the rotation shaft 204 rotates so that the stirring member 205 rotates clockwise.

  As shown in FIG. 13, the weight 202 is a protruding portion that protrudes from the plate surface of the diaphragm 201 and has a shape that is inclined with respect to the plate surface of the diaphragm 201 when viewed from the side. This inclination is configured such that the inclined surface approaches the rotating shaft 204 along the rotation direction of the stirring member 205. The inclined surface of the weight 202 is a portion that is pushed by the stirring member 205 when the stirring member 205 repels and vibrates the vibration plate 201. FIG. 14 is a side view showing a state where the stirring member 205 is further rotated from the state shown in FIG.

  By further rotating the stirring member 205 in contact with the weight 202, the vibration plate 201 is pushed and deformed with the inclination provided in the weight 202. In FIG. 14, the positions of the diaphragm 201 and the weight 202 in a state where no external force is applied (hereinafter referred to as “steady state”) are indicated by broken lines. As shown in FIG. 14, the diaphragm 201 and the weight 202 are pushed in by the stirring member 205.

  15 is a top view showing the state shown in FIG. Since the diaphragm 201 is fixed to the inner wall of the housing of the sub hopper 200 via the fixing portion 201a, the position on the fixing portion 201a side does not change. On the other hand, the end on the opposite side which is provided with the weight 202 and is a free end moves to the side opposite to the side on which the rotating shaft 204 is provided by being pushed by the stirring member 205. As a result, the diaphragm 201 bends as shown in FIG. 15 with the fixed portion 201a as a base point. In such a bent state, energy for vibrating the diaphragm 201 is stored.

  As shown in FIG. 15, the stirring member 205 according to the present embodiment is provided with a cut 205 a between a portion that contacts the weight 202 and the other portion. Thereby, it is possible to prevent the stirring member 205 from being damaged by applying an excessive force when the stirring member 205 pushes the weight 202.

  In addition, a round portion 205b is provided at the starting point of the cut 205a. Thereby, when the amount of bending of the stirring member 205 differs from the notch 205a as a boundary, the stress applied to the starting point of the notch 205a can be dispersed, and the stirring member 205 can be prevented from being damaged.

  FIG. 16 is a side view showing a state where the stirring member 205 is further rotated from the state shown in FIG. In FIG. 16, the position of the diaphragm 201 in a steady state is indicated by a broken line, and the position of the diaphragm 201 shown in FIG. 14 is indicated by a chain line. The position of the diaphragm 201 that has been deflected to the opposite side when the vibration energy stored by being pushed in by the stirring member 205 is released is indicated by a solid line.

  FIG. 17 is a top view showing the state shown in FIG. As shown in FIG. 16, when the weight 202 is pressed by the stirring member 205, the end portion on the side where the weight 202, which is a free end, is provided on the opposite side due to the bending energy stored in the diaphragm 201. Move to bend.

  In the state shown in FIGS. 16 and 17, the diaphragm 201 is in a state where it is away from the magnetic flux sensor 10 facing through the housing of the sub hopper 200. Thereafter, the vibration plate 201 vibrates to return to the steady state due to vibration attenuation while repeating the state closer to the magnetic flux sensor 10 than the steady state and the state away from the steady state.

  FIG. 18 is a diagram schematically showing the state of toner held in the sub hopper 200 with dots. As shown in FIG. 18, when the toner exists in the sub hopper 200, the vibration plate 201 and the weight 202 come into contact with the toner while vibrating. Therefore, the vibration of the vibration plate 201 is attenuated faster than when no toner is present in the sub hopper 200. The remaining amount of toner in the sub hopper 200 can be detected based on the change in vibration attenuation.

  FIG. 19 is a diagram illustrating a change in the count value of the oscillation signal of the magnetic flux sensor 10 every predetermined period after the weight 202 is bounced by the stirring member 205 until the vibration of the diaphragm 201 is attenuated and the vibration stops. is there. The count value of the oscillation signal of the magnetic flux sensor 10 increases as the oscillation frequency increases. Accordingly, the vertical axis in FIG. 19 can be replaced with the oscillation frequency instead of the count value.

As shown in FIG. 19, when the stirring member 205 comes into contact with the weight 202 and pushes the weight 202 at timing t ₁ , the diaphragm 201 approaches the magnetic flux sensor 10. Thereby, the oscillation frequency of the magnetic flux sensor 10 rises and the count value for every predetermined period rises.

Then, the release pressing of the weight 202 by a stirring member 205 at the timing t _2, since the diaphragm 201 is vibrated by the vibration energy stored. When the vibration plate 201 vibrates, a state where the distance between the vibration plate 201 and the magnetic flux sensor 10 is wider and narrower is repeated centering on a steady state. As a result, the frequency of the oscillation signal of the magnetic flux sensor 10 vibrates with the vibration of the diaphragm 201, and the count value for each predetermined period also vibrates in the same manner.

  The amplitude of vibration of the diaphragm 201 becomes narrower as the vibration energy is consumed. That is, the vibration of the diaphragm 201 attenuates with time. For this reason, the change in the distance between the diaphragm 201 and the magnetic flux sensor 10 also decreases with time, and the time change in the count value also changes as shown in FIG.

  Here, as described above, the vibration of the vibration plate 201 attenuates earlier as the amount of remaining toner in the sub hopper 200 increases. Accordingly, by analyzing how the vibration of the oscillation signal of the magnetic flux sensor 10 as shown in FIG. 19 is analyzed, it is recognized how the vibration of the diaphragm 201 has been attenuated, and thereby the toner remaining inside the sub hopper 200 is recognized. You can know the amount.

Therefore, as shown in FIG. 19, assuming that the vibration peaks of the count value are P1, P2, P3, P4,..., For example, the vibration attenuation rate ζ of the diaphragm 201 is expressed by the following equation (2). Can be requested. By referring to the ratio of the peak values having different timings as shown in the expression (2), it is possible to cancel the error due to the environmental variation and obtain the accurate attenuation rate. In other words, the CPU 21 according to the present embodiment obtains the attenuation rate ζ based on the ratio of the count values acquired at different timings.

In the above formula (2), P ₁ , P ₂ and P ₅ , P ₆ among the peaks shown in FIG. 19 are used. However, this is an example, and other peaks may be used. However, the peak value at the timing t ₂ is a state where the vibration plate 201 closest to the magnetic flux sensor 10 is pushed by the stirring member 205, an error such as the sliding noise due to friction between the agitating member 205 and the weight 202 are superposed Therefore, it is preferable not to be a calculation target.

  As shown in FIG. 18, even if the attenuation of vibration is accelerated by the presence of toner inside the sub hopper 200, the vibration frequency of the vibration plate 201 does not change greatly. Therefore, by calculating the ratio of the amplitude of a specific peak as shown in the above formula (2), it is possible to calculate the attenuation of the amplitude in a predetermined period.

  Next, the operation of detecting the remaining amount of toner in the sub hopper 200 according to the present embodiment will be described with reference to the flowchart of FIG. The operation of the flowchart shown in FIG. 20 is the operation of the CPU 21 shown in FIG. As shown in FIG. 20, the CPU 21 first detects that the weight 202 is pushed in by the stirring member 205 as shown in FIG. 14 and vibration is generated (S2001).

As described above, the CPU 21 acquires the count value of the output signal of the magnetic flux sensor 10 from the count value output unit 33 every predetermined period. This count value is C ₀ as shown in FIG. 19 in the steady state. In contrast, when the weight 202 is pushed in as shown in FIG. 14, the count value increases as the diaphragm 201 approaches the magnetic flux sensor 10. Therefore, the CPU 21 detects that vibration has occurred in S2001 when the count value acquired from the count value output unit 33 exceeds a predetermined threshold value.

  Regardless of the time before and after S2001, the CPU 21 continues to acquire the count value every predetermined period as a normal process. Then, after S2001, the CPU 21 acquires the peak value of the vibration of the count value corresponding to the vibration of the diaphragm 201 as shown in FIG. 19 (S2002). In S2002, the CPU 21 specifies the peak value by continuously analyzing the count value acquired every predetermined period.

FIG. 21 is a diagram showing an analysis mode of the count value. Regarding the count value acquired every predetermined period, in addition to the _respective count values “number n” and “count value S _n ”, the previous count value The difference sign “S _n−1 −S _n ” is shown in the order of acquisition. In the result as shown in FIG. 21, the value immediately before the sign of “S _n−1 −S _n ” is inverted is the peak value. In the case of FIG. 21, No. 5 and No. 10 are adopted as peak values.

That is, the CPU 21 calculates “S _n−1 −S _n ” shown in FIG. 21 for the count values acquired in order after S 2001. Then, the “count value S _n ” at the timing when the sign obtained as the calculation result is inverted is adopted as the peak values such as P ₁ , P ₂ , P ₃ ... Shown in FIG.

As described above, the value at the timing t ₂ is preferably avoided. The value of the timing _{t 2} is the first peak after S2001. Therefore, the CPU 21 discards the first value among the peak values extracted by performing the analysis as shown in FIG.

The actually obtained count value may contain high-frequency component noise, and the timing at which the sign of “S _n−1 −S _n ” is reversed at a position that is not a peak due to vibration of the diaphragm 201. May occur. In order to avoid erroneous detection in such a case, the CPU 21 preferably performs the analysis shown in FIG. 21 after smoothing the value acquired from the count value output unit 33. In the smoothing process, a general process such as a moving average method can be employed.

When the peak value is acquired in this way, the CPU 21 calculates the attenuation factor ζ by the calculation of the above equation (2) (S2003). For this reason, in S2002, the count value is analyzed by the mode shown in FIG. 21 until the peak value used for calculating the attenuation rate is obtained. When using the above formula (2), CPU 21 analyzes the count value to a peak value corresponding to P ₆ is obtained.

  When the attenuation rate ζ is calculated in this way, the CPU 21 determines whether or not the calculated attenuation rate ζ is equal to or less than a predetermined threshold (S2004). That is, the CPU 21 determines that the toner in the sub hopper 200 has fallen below a predetermined amount based on the magnitude relationship between the ratio of the count values acquired at different timings and the predetermined threshold value. As described with reference to FIG. 18, when sufficient toner remains in the sub hopper 200, the vibration of the vibration plate 201 is quickly attenuated. Therefore, the attenuation rate ζ becomes small.

On the other hand, when the toner in the sub hopper 200 decreases, the vibration of the vibration plate 201 is attenuated accordingly, and the attenuation factor ζ increases. Therefore, by setting the attenuation rate ζ _S according to the remaining amount of toner to be detected as a threshold, the remaining amount of toner in the sub hopper 200 to be detected (hereinafter, “ It is possible to determine that the amount has been reduced to “the prescribed amount”.

  The remaining amount of toner in the sub hopper 200 does not directly affect the vibration attenuation mode of the vibration plate 201, but the contact state of the toner with respect to the vibration plate 201 changes according to the remaining amount of toner. The vibration attenuation mode 201 is determined. Therefore, even if the remaining amount of toner in the sub hopper 200 is the same, if the toner contact mode with respect to the vibration plate 201 is different, the vibration mode of the vibration plate 201 is different.

  On the other hand, when detecting the remaining amount of toner inside the sub hopper 200 according to the present embodiment, the toner inside the sub hopper 200 is always stirred by the stirring member 205. Therefore, the toner contact state with respect to the vibration plate 201 can be determined to some extent according to the remaining amount of toner. Thereby, even if the remaining amount of toner is the same amount, it is possible to avoid the adverse effect that the detection result varies due to the difference in the toner contact mode with respect to the vibration plate 201.

  If the calculated attenuation rate ζ is less than the threshold value as a result of the determination in S2004 (S2004 / NO), the CPU 21 determines that a sufficient amount of toner is held in the sub hopper 200 and ends the process as it is. To do. On the other hand, if the calculated attenuation rate ζ is equal to or greater than the threshold (S2004 / YES), the CPU 21 determines that the amount of toner in the sub hopper 200 is below the specified amount, detects toner out, and ends the process. (S2005).

  The CPU 21 that has detected that the toner has run out in the process of S2005 outputs a signal indicating that the remaining amount of toner has fallen below the specified amount to a higher-order controller that controls the image forming apparatus 100. As a result, the controller of the image forming apparatus 100 can recognize that the specific color is out of toner and supply toner from the toner bottle 117.

Next, the relationship among the frequency of the oscillation signal of the magnetic flux sensor 10 according to the present embodiment, the count value acquisition cycle by the CPU 21 (hereinafter referred to as “sampling cycle”), and the natural frequency of the diaphragm 201 will be described. FIG. 22 is a diagram illustrating sampled count values for vibrations in one period of the diaphragm 201. In FIG. 22, the vibration period of the diaphragm 201 is T _plate and the sampling period is T _sample .

In order to calculate the attenuation factor ζ of the diaphragm 201 with high accuracy according to the mode described in FIGS. 19 to 21, it is necessary to acquire the peak value of vibration of the diaphragm 201 with high accuracy. For this purpose, the number of samples having a sufficient count value for T _plate is necessary, and therefore, T _sample needs to be sufficiently small for T _plate .

In the example of FIG. 22, the number of samples of the count value is 10 for one cycle of T _plate . That is, T _sample is 1/10 of T _plate . According to the aspect of FIG. 22, sampling is always performed within the period of T _{peak in} the figure, and the peak value can be acquired with high accuracy.

Therefore, if the sampling period T _{sample of the} CPU 21 is 1 ms, the vibration period T _plate of the diaphragm 201 is preferably 10 ms or more. In other words, with respect to the sampling frequency of 1000 Hz of the CPU 21, the natural frequency of the diaphragm 201 is preferably about 100 Hz, and more preferably less than that. Such a natural frequency of the diaphragm 201 is realized by adjusting the material of the diaphragm 201, the dimensions including the thickness of the diaphragm 201, and the weight of the weight 202.

  On the other hand, if the value of the count value sampled at each sampling period is too small, the change in the count value for each sample according to the vibration of the diaphragm 201 becomes small, and the attenuation rate ζ cannot be calculated accurately. Here, the value of the count value to be sampled is a value according to the oscillation frequency of the magnetic flux sensor 10.

Generally, the oscillation frequency of the magnetic flux sensor 10 is on the order of several MHz. When sampling is performed at a sampling frequency of 1000 Hz, a count value of 1000 or more can be obtained at each sampling timing. Therefore, the attenuation rate ζ can be calculated with high accuracy according to the order of T _plate and T _sample as described above.

  However, if the amount of change in the oscillation frequency of the magnetic flux sensor 10 is not sufficient with respect to the change in the distance between the magnetic flux sensor 10 and the vibration plate 201 due to the vibration of the vibration plate 201, the count value with respect to time as shown in FIG. The amplitude of vibration becomes small. As a result, the change in the attenuation rate ζ is also reduced, and the accuracy of the toner remaining amount detection due to the vibration of the vibration plate 201 is also lowered.

  In order to increase the amount of change in the oscillation frequency of the magnetic flux sensor 10 with respect to the change in the distance between the magnetic flux sensor 10 and the diaphragm 201, the arrangement of the magnetic flux sensor 10 and the diaphragm 201 is based on the characteristics shown in FIG. The interval needs to be determined. For example, as shown in the section indicated by the arrow in the figure, the interval between the magnetic flux sensor 10 and the diaphragm 201 is set to an interval in which the change in the oscillation frequency with respect to the change in the interval between the magnetic flux sensor 10 and the diaphragm 201 is included in a steep range. It is preferable to determine the interval.

  FIG. 23 is a diagram illustrating an adjustment mode of the arrangement interval between the magnetic flux sensor 10 and the vibration plate 201. As shown in FIG. 23, the adjustment of the arrangement interval g between the magnetic flux sensor 10 and the diaphragm 201 is performed by fixing the thickness of the housing 200a of the sub hopper 200 to which the magnetic flux sensor 10 and the diaphragm 201 are attached, and the diaphragm 201 being fixed. It is possible to adjust according to the thickness of the fixing portion 201a.

  As described above, according to the method for detecting the remaining amount of toner according to the present embodiment, the influence of the toner on the delicate event of vibration of the vibration plate 201 is detected. Also, unlike the case of directly detecting the toner pressure or the like, since the detection is performed through the vibration of the diaphragm, the remaining amount of toner in the container is increased without using a pressure sensor that is difficult to improve accuracy. It becomes possible to detect with accuracy.

  Moreover, it is a premise that the diaphragm 201 to be sensed by the magnetic flux sensor 10 used as a sensor in the present embodiment is vibrating. Therefore, even if the toner adheres to the vibration plate 201, the toner attached by the vibration is shaken off, and it is possible to avoid a decrease in detection accuracy due to the adhesion of the toner.

  Further, no physical contact is required between the magnetic flux sensor 10 used as a sensor in the present embodiment and the diaphragm 201 that is a sensing target. Therefore, even if the magnetic flux sensor 10 is provided outside the toner container, it is not necessary to make a hole in the container housing to ensure physical access. Therefore, it can be easily attached and productivity can be improved.

  Further, according to the aspect of this embodiment, the detection of the remaining amount of toner is triggered by the fact that the vibration plate 201 is displaced by being pressed by the stirring member 205 as in S2001, and the subsequent peak value is acquired. Executed. Therefore, in the state where the vibration plate 201 is pushed in by the stirring member 205 as shown in FIG.

  On the other hand, in the case of detecting the pressure corresponding to the remaining amount of toner with a pressure sensor or the like, the pressure pressed by the stirring member for stirring the toner in the container and the pressure generated according to the remaining amount of toner It is difficult to distinguish and it is difficult to improve detection accuracy. According to the aspect which concerns on this embodiment, such a subject can be solved.

  In the above-described embodiment, the case where the diaphragm 201 which is a plate member made of a metal material is used as an object of sensing by the magnetic flux sensor 10 has been described as an example. However, this is an example. The conditions required for the diaphragm 201 are that vibration with a predetermined frequency as described with reference to FIG. It affects the frequency.

  In the above embodiment, a metal material that cancels the magnetic flux and decreases the inductance L as it approaches the magnetic flux sensor 10 is used. The material may be used.

  In the above embodiment, the vibration plate 201 that is a plate-like member is the sensing target of the magnetic flux sensor 10 from the viewpoint of affecting the magnetic flux generated by the planar pattern coil 11 of the magnetic flux sensor 10 and from the viewpoint of the natural frequency. However, this is only an example, and as long as the condition that it vibrates and affects the magnetic flux is satisfied, it is not limited to a plate shape but may be a rod-shaped component.

  Moreover, in the said embodiment, the diaphragm 201 was formed using the material which affects magnetic flux, and the aspect which detects attenuation | damping of the vibration of the diaphragm 201 by the magnetic flux sensor 10 was demonstrated as an example. However, this is merely an example, and any mode may be used as long as the remaining amount of toner in the container is detected by the influence of the toner on the delicate event of damping the vibration of the plate-like member.

  Further, the above-mentioned specified amount can be adjusted by the arrangement of the diaphragm 201 and the magnetic flux sensor 10 in the sub hopper 200. 24 and 25 are diagrams showing the relationship between the arrangement of the diaphragm 201 and the magnetic flux sensor 10 in the sub hopper 200 and the specified amount. In the case of FIG. 24, when the height of the toner held inside the sub hopper 200 becomes lower than the height of the broken line A shown in the figure, the toner does not contact the vibration plate 201. Accordingly, it is detected that the remaining amount of toner is below the specified amount in the vicinity of the height of the broken line A in the drawing.

  On the other hand, in the case of FIG. 25, the arrangement height of the diaphragm 201 and the magnetic flux sensor 10 is lower than that in FIG. When the height of the toner held inside the sub hopper 200 becomes lower than the height of the broken line B shown in the drawing, the toner does not contact the vibration plate 201. Therefore, in the vicinity of the height of the broken line B in the figure, it is detected that the remaining amount of toner is below the specified amount.

  In this way, the mode in which the specified amount is adjusted by the arrangement of the vibration plate 201 and the magnetic flux sensor 10 can be used, for example, to adjust the supply state of the CMYK color toners. For example, for CMYK frequently used colors, the diaphragm 201 and the magnetic flux sensor 10 are arranged relatively high as shown in FIG. On the other hand, for colors that are used infrequently, the diaphragm 201 and the magnetic flux sensor 10 are arranged relatively low as shown in FIG. Such adjustment makes it possible to efficiently supply toner according to the frequency of use.

  Further, in the above-described embodiment, as an example, the configuration including the magnetic flux sensor 10 and the diaphragm 201 is used as a mechanism for detecting the remaining amount of toner in the sub hopper 200 illustrated in FIG. However, the above configuration can be widely used as a configuration for detecting the amount of toner that is powder, and for example, can be used as a configuration for detecting the remaining amount of toner in the developing device 112.

  FIG. 26 is a cross-sectional view when employed in the developing device 112. Inside the developing device 112, a supply chamber conveyance member 112b and a recovery chamber conveyance member 112c, which are screws for conveying toner throughout the main scanning direction, rotate to convey the toner.

  When the configuration including the magnetic flux sensor 10 and the vibration plate 201 is adopted in the developing device 112, as shown in FIG. 26, the magnetic flux sensor 10 has a surface on which the planar pattern coil 11 is formed at a sensor mounting position 112a in the developing device 112. Mounted face to face. As a result, as shown in FIG. 26, the planar pattern coil 11 is arranged so as to face the developer moving space where the transport path by the collection chamber transport member 112c and the transport path by the supply chamber transport member 112b are connected. .

  Inside the developing device 112, the vibration plate 201 is disposed in the developer moving space. The vibration plate 201 arranged inside the developing device 112 is bounced and vibrated by the rotating collection chamber transport member 112c, similarly to the case where it is provided in the sub hopper 200. Thereby, the vibration of the diaphragm 201 can be detected by the magnetic flux sensor 10 as described above.

  In the developer moving space, the toner moves between the transport path by the collection chamber transport member 112c and the transport path by the supply chamber transport member 112b. The toner density increases. Therefore, by arranging the vibration plate 201 in the developer movement space as shown in FIG. 26, the influence of the toner on the vibration of the vibration plate 201 is increased, and the remaining amount of toner in the developing device 112 is detected with high accuracy. Is possible.

  In the above-described embodiment, the toner that is the developer used in the electrophotographic image forming apparatus has been described as an example of the powder for which the remaining amount is detected. However, this is merely an example, and any powder that has fluidity and affects the vibration of the diaphragm 201 according to the remaining amount can be applied in the same manner. For example, a premixed toner and developer are mixed. It can be applied to mix agents. Further, not only powder, but also a substance that affects the vibration of the diaphragm 201 depending on the remaining amount by having fluidity can be similarly set as a detection target of the remaining amount. It is also possible to adopt.

Moreover, in the said embodiment, the case where attenuation factor (zeta) was calculated by said Formula (2) was demonstrated as an example. However, this is only an example, and for example, an average value of attenuation factors between a plurality of peaks may be used as in the following Expression (3).

Moreover, as shown in the following formula (4), the ratio of peak values may be simply used.

  Moreover, in the said embodiment, the case where the planar pattern coil formed by patterning on the board | substrate was used was demonstrated as an example. By forming the coil on a plane, it is possible to reduce the thickness in the direction facing the diaphragm 201 that is the sensing target, and it is possible to suitably achieve downsizing of the device.

  However, the same effect can be obtained by forming the coil so that the magnetic flux is generated in parallel to the direction facing the diaphragm 201 without forming the coil by a planar pattern. Another example of the coil formation mode is shown in FIGS. 27 is a view seen from a direction parallel to the plate surface of the substrate constituting the magnetic flux sensor 10, and FIG. 28 is a view seen from a direction perpendicular to the plate surface of the substrate constituting the magnetic flux sensor 10.

  In the example of FIGS. 27 and 28, the coil 11 ′ is formed by winding and arranging the wiring whose surface is insulated on the substrate constituting the magnetic flux sensor 10. In the examples of FIGS. 27 and 28 as well, the thickness of the coil 11 ′ can be sufficiently reduced by appropriately selecting the type of wiring, and the apparatus can be miniaturized.

  Next, a description will be given of suitable mounting modes of the diaphragm 201, the fixing portion 201a, the weight 202 (hereinafter, collectively referred to as “vibrating structure 210”), and the magnetic flux sensor 10 according to the present embodiment. FIGS. 29A to 29D are views showing an aspect of attachment of the vibration structure 210 and the magnetic flux sensor 10 according to the present embodiment.

  FIG. 29A is a perspective view showing the sub hopper 200 before the vibration structure 210 and the magnetic flux sensor 10 are attached. FIG. 29B is a perspective view showing the sub hopper 200 to which the vibration structure 210 and the magnetic flux sensor 10 are attached. FIG. 29C is a top view showing the sub hopper 200 to which the vibration structure 210 and the magnetic flux sensor 10 are attached. FIG. 29D is a cross-sectional view taken along a cutting line AA ′ in FIG.

  As shown in FIGS. 29A and 29B, in the sub hopper 200 according to the present embodiment, the vibration structure 210 is attached to the inner wall of the housing of the sub hopper 200, and the magnetic flux sensor is attached to the outer wall. 10 is attached. Then, as shown in FIGS. 29C and 29D, the vibration structure 210 and the magnetic flux sensor 10 are arranged to face each other across the wall of the housing.

  When attaching the vibration structure 210 and the magnetic flux sensor 10 as shown in FIGS. 29A to 29D, attachment by adhesion via an adhesive layer is performed. Thereby, it is not necessary to provide a through hole in the wall surface of the housing as in the case of attaching using a fastening member such as a screw. Therefore, it is possible to prevent internal toner from leaking from the through hole and scattering to the outside of the sub hopper. In other words, the space in which the vibration structure 210 is disposed and the space in which the magnetic flux sensor 10 is disposed are blocked in a direction in which both face each other. Therefore, the leakage of toner can be prevented.

  In addition, according to the attachment modes shown in FIGS. 29A to 29D, since a fastening member such as a screw is not necessary, the cost can be reduced by reducing the number of parts, and the assembly work can be facilitated by reducing the fastening work. This can improve productivity. In addition, when the through hole is provided, the above-described sealing member for preventing the scattering of the toner is necessary, but the mounting mode according to the present embodiment also does not need this, so further cost reduction and assembly work Can be facilitated.

  In FIGS. 29A to 29D, the vibration structure 210 is shown based on a state in which the diaphragm 201, the fixing portion 201a, and the weight 202 are integrated. As shown in FIG. 29A, the sub-hopper 200 may be assembled in such an integrated configuration, or the fixing portion 201a, the diaphragm 201, and the weight 202 may be assembled in this order. Further, when attaching the fixing portion 201a and the weight 202 to the vibration plate 201, various methods such as welding, welding, caulking, and adhesion can be used.

  FIGS. 30A to 30D are diagrams illustrating other attachment modes of the vibration structure 210 and the magnetic flux sensor 10 according to the present embodiment. FIG. 30A is a perspective view showing the sub hopper 200 before the vibration structure 210 and the magnetic flux sensor 10 are attached. FIG. 30B is a perspective view showing the sub hopper 200 to which the vibration structure 210 and the magnetic flux sensor 10 are attached. FIG. 30C is a top view showing the sub hopper 200 to which the vibration structure 210 and the magnetic flux sensor 10 are attached. FIG. 30D is a cross-sectional view taken along a cutting line AA ′ in FIG.

  The modes shown in FIGS. 30 (a) to 30 (d) are mounting modes by fitting into ribs that are concave portions. Therefore, as shown in FIG. 30A, ribs 200a are provided on the inner wall of the housing of the sub hopper 200, and ribs 200b are provided on the outer wall.

  Then, as shown in FIG. 30A, the vibration structure 210 is fixed to the inside of the housing of the sub hopper 200 by fitting the vibration structure 210 into the rib 200a. Further, as shown in FIG. 30 (d), the magnetic flux sensor 10 is fixed to the outside of the housing of the sub hopper 200 by fitting the magnetic flux sensor 10 into the rib 200 b.

  In the embodiments shown in FIGS. 30A to 30D as well, it is possible to prevent toner scattering by not providing a through-hole in the housing of the sub hopper 200. Moreover, the operation | work of fastening of a screw etc. is unnecessary and it is the same also that the assembly | attachment operation | work becomes easy. Furthermore, the cost can be reduced by reducing the number of parts such as fastening members and seal members.

  Here, in the example of FIGS. 30A to 30D, as shown in FIGS. 30A and 30D, the upper end of the fixing portion 201a that holds the diaphragm 201 in the vibration structure 210. Is provided with a flat portion 210a formed in a key shape. In other words, the flat portion 210a is a structure portion for forming a surface that is substantially perpendicular to the fitting direction when the vibration structure 210 is fitted into the rib 200a.

  Thereby, when attaching the vibration structure 210 to the rib 200a, the flat portion 210a becomes a pressed portion to be pressed by the operator. Therefore, the operator can push the flat portion 210a to push the vibrating structure 210 into the rib 200a, and the attachment work can be facilitated.

  Although not shown in FIG. 30D, the magnetic flux sensor 10 may be provided with a configuration corresponding to the flat portion 210a of the vibration structure 210. Thereby, the operation | work at the time of pushing the magnetic flux sensor 10 into the rib 200b can be made easy. According to the modes of FIGS. 30A to 30D, the adhesive layer can be reduced as compared with the modes of FIGS. 29A to 29D, thereby further reducing the cost and facilitating the work. Can be planned.

  Moreover, you may combine the aspect by adhesion | attachment shown to Fig.29 (a)-(d), and the aspect by fitting shown in Fig.30 (a)-(d). For example, a mode in which the vibration structure 210 is attached and the magnetic flux sensor 10 is attached by fitting, or a mode in which the vibration structure 210 is fitted and the magnetic flux sensor 10 is attached by bonding can be considered.

  29 (a) to (d) and FIGS. 30 (a) to (d), by attaching the fixing portion 201a to the diaphragm 201, the wall surface of the casing of the sub hopper 200 and the diaphragm The space | interval with 201 is ensured. However, this is only an example, and a structure corresponding to the fixing portion 201a may be provided depending on the shape of the inside of the housing of the sub hopper 200, and the diaphragm 201 may be attached to the structure.

DESCRIPTION OF SYMBOLS 10 Magnetic flux sensor 11 Planar pattern coil 12 Pattern resistance 13 1st capacitor 14 2nd capacitor 15 Feedback resistance 16, 17 Unbuffer IC
18 Output terminal 20 Controller 21 CPU
22 ASIC
23 Timer 24 Crystal Oscillator 30 I / O Control ASIC
31 Magnetic permeability counter 32 Read signal acquisition unit 33 Count value output unit 101 Paper feed tray 102 Paper feed roller 103 Registration roller 104 Paper 105 Conveying belt 106K, 106C, 106M, 106Y Image forming unit 107 Drive roller 108 Drive roller 109K, 109C, 109M, 109Y Photosensitive drum 110K, 110C, 110M, 110Y Charger 111 Optical writing device 112, 112K, 112C, 112M, 112Y Developer 112a Sensor mounting position 112b Supply chamber transport member 112c Collection chamber transport member 113K, 113C, 113M, 113Y Photoconductor cleaner 115K, 115C, 115M, 115Y Transfer device 116 Fixing device 117 Toner bottle 118 Belt cleaner 119 Sub hopper supply path 120 Toner Torr supply path 200 sub hopper 200a, 200b rib 201 diaphragm 201a fixed part 202 weight 204 rotates shaft 205 stirring member 205a cuts 205b round part 210 vibrating structure 210a flats

JP 2013-37280 A

Claims (6)

A powder detection device for detecting the remaining amount of powder having fluidity in a container,
A vibrating portion that is disposed inside the container and vibrates under the influence of powder inside the container;
A vibration detection unit for detecting a vibration state of the vibration unit;
A vibration applying unit that vibrates the vibrating unit;
A detection processing unit that detects a residual amount of powder in the container based on a detection result by the vibration detection unit,
The vibration part and the vibration detection part are arranged to face each other through the casing of the container,
The powder detection device, wherein the space in which the vibration unit is disposed and the space in which the vibration detection unit is disposed are blocked in a direction in which the vibration unit and the vibration detection unit face each other.   The powder detection apparatus according to claim 1, wherein at least one of the vibration unit and the vibration detection unit is attached to the casing of the container by adhesion.   3. The powder detection device according to claim 1, wherein at least one of the vibration part and the vibration detection part is fitted into a recess with respect to a housing of the container.   Of the vibration part and the vibration detection part, the one fitted into the recess with respect to the casing of the container is constituted by a surface substantially perpendicular to the direction to be fitted into the recess and is fitted into the recess. The powder detection device according to claim 3, further comprising a pressed portion that is pressed at the time.   5. A developer remaining amount detection device that detects the remaining amount of a developer used in an image forming apparatus by the powder detection device according to claim 1.   An image forming apparatus comprising the developer remaining amount detecting device according to claim 5.