JP7484598B2 - Lubricant remaining amount estimation device, image forming apparatus, and lubricant remaining amount estimation method - Google Patents

Description

The present invention relates to a lubricant remaining amount estimation device, an image forming device, and a lubricant remaining amount estimation method.

Electrophotographic image forming devices (printers, copiers, facsimiles, and all-in-one machines) are equipped with cleaning devices having cleaning blades that remove residual toner remaining on image carriers such as photoreceptor drums and intermediate transfer belts. Some devices also include a lubricant supplying device that supplies a lubricant (slip agent) onto the image carrier to reduce the friction between the image carrier and the cleaning blade and smoothly clean the residual toner on the image carrier (see, for example, Patent Document 1).

In the above-mentioned cleaning device, it is desirable to extend its lifespan in terms of image quality and costs of the image forming device. By providing the above-mentioned lubricant supply device, it is possible to extend the lifespan of the cleaning device by reducing the frictional force between the image carrier and the cleaning blade and reducing wear on the image carrier and cleaning blade.

JP 2014-167598 A

However, the lubricant supplied to the image carrier is a consumable item. Therefore, when the lubricant runs out, for example, the frictional force between the image carrier and the cleaning blade increases, which may adversely affect the life of the cleaning device, as described below.

For example, in the case of a cleaning device with replaceable lubricant, if the currently installed lubricant runs out before it can be replaced with new lubricant, the frictional force between the image carrier and the cleaning blade will increase. If the frictional force between the image carrier and the cleaning blade increases, it may cause poor cleaning of the residual toner on the image carrier, or cause toner filming, in which toner components are thinly adhered to the image carrier. As a result, it becomes impossible to continue using the cleaning device.

In Patent Document 1, the remaining amount of lubricant is determined by the electrical continuity between the electrode on the brush side that supplies the lubricant and the electrode on the lubricant side. In such mechanical detection means, the amount of remaining lubricant may not be detected correctly because the detection part becomes dirty due to scattering of toner and lubricant powder. In addition, since it is determined whether the lubricant is depleted or not by the electrical continuity between the electrode on the brush side and the electrode on the lubricant side, it is not possible to detect how much lubricant is remaining.

Therefore, it is necessary to replace the lubricant before it runs out, and in a configuration in which the lubricant is replaced, it is desirable to accurately grasp the remaining amount of lubricant currently being used.

The object of the present invention is to provide a lubricant remaining amount estimation device, an image forming device, and a lubricant remaining amount estimation method that can accurately grasp the remaining amount of lubricant.

The lubricant remaining amount estimation device according to the present invention comprises:
a resonance sound generating unit that generates different resonance sounds in response to a change in the remaining amount of lubricant supplied to the image carrier;
a remaining amount estimation unit that estimates the remaining amount of the lubricant based on the generated resonance sound;
Equipped with.

The image forming apparatus according to the present invention comprises:
The lubricant remaining amount estimation device is provided.

The method for estimating the remaining amount of lubricant according to the present invention comprises the steps of:
The remaining amount of lubricant is estimated based on a resonance sound generated by a resonance sound generating unit which generates different resonance sounds according to changes in the remaining amount of lubricant supplied to the image carrier.

The present invention allows the remaining amount of lubricant to be accurately estimated.

1 is a diagram illustrating an overall configuration of an image forming apparatus according to an embodiment of the present invention. 2 is a diagram showing a main part of a control system of the image forming apparatus according to the embodiment of the present invention; FIG. 2 is a diagram showing a drum cleaning unit of the image forming apparatus. 4 is a diagram illustrating removal of a lubricant pressing mechanism in the drum cleaning unit shown in FIG. 3. FIG. FIG. 4 is a view showing the lubricant pressing mechanism disassembled into the lubricant side and the storage section side. 13 is a diagram showing the internal state of the lubricant pressing mechanism at the beginning of use of the lubricant. FIG. FIG. 13 is a diagram showing the internal state of the lubricant pressing mechanism at the end of the lubricant use. 1 is a diagram showing a configuration example (configuration example 1) of a lubricant remaining amount estimation device according to an embodiment of the present invention; 9 is a graph showing a relationship between a flow path width of a resonance sound generating portion and a peak frequency of a resonance sound in the lubricant remaining amount estimating device shown in FIG. 8 . 9 is a graph showing the relationship between the peak frequency of resonance sound and the height of lubricant in the remaining lubricant amount estimating device shown in FIG. 8 . FIG. 4 is a diagram showing another configuration example (configuration example 2) of the lubricant remaining amount estimating device according to the embodiment of the present invention. FIG. 4 is a diagram showing another configuration example (configuration example 3) of the lubricant remaining amount estimating device according to the embodiment of the present invention. 13 is a graph showing the relationship between the height of the lubricant and the flow path width of the resonance sound generating portion in the lubricant remaining amount estimating device shown in FIG. 12 . 13 is a graph showing the relationship between the flow path width of the resonance generating portion and the peak frequency of the resonance in the lubricant remaining amount estimating device shown in FIG. 12 . 13 is a graph showing the relationship between the peak frequency of resonance sound and the height of lubricant in the remaining lubricant amount estimating device shown in FIG. 12 . FIG. 13 is a diagram showing a modified example of the lubricant remaining amount estimating device shown in FIG. 12. FIG. 11 is a diagram showing another configuration example (configuration example 4) of the lubricant remaining amount estimating device according to the embodiment of the present invention. FIG. 5 is a diagram showing another configuration example (configuration example 5) of a lubricant remaining amount estimating device according to an embodiment of the present invention. FIG. 13 is a diagram showing a configuration example (configuration example 6) of a lubricant supplying device of an image forming apparatus according to an embodiment of the present invention. 1 is a graph showing the relationship between the lubricant height and the rotation speed of the application brush. 4 is a flowchart illustrating a control method of a remaining lubricant amount estimating device including a remaining lubricant amount estimating method.

The following describes in detail the embodiments of the present invention with reference to the drawings.

Figure 1 is a diagram showing the overall configuration of an image forming apparatus 1 according to the present embodiment. Figure 2 is a diagram showing the main parts of the control system of the image forming apparatus 1 according to the present embodiment. Note that the image forming apparatus 1 is an example of the present embodiment, and its configuration and specifications are not limited to those described below and can be modified as appropriate.

As shown in FIG. 1, the image forming device 1 is a color image forming device of the intermediate transfer type that utilizes electrophotographic process technology. That is, the image forming device 1 forms an image by primarily transferring each of the CMYK color toner images formed on the photosensitive member to an intermediate transfer body, superimposing the four color toner images on the intermediate transfer body, and then secondary transferring the images onto a recording medium, namely paper. Note that CMYK stands for C (cyan), M (magenta), Y (yellow), and K (black).

The image forming device 1 also uses a tandem system in which photoconductors corresponding to the four colors CMYK are arranged in series in the running direction of the intermediate transfer body, and each color toner image is transferred sequentially to the intermediate transfer body in a single step.

As shown in FIG. 1, the image forming device 1 includes an image reading unit 10, an operation display unit 20, an image processing unit 30, an image forming unit 40, a paper transport unit 50, and a fixing unit 60.

The image reading unit 10 includes an automatic document feeder 11, also known as an ADF (Auto Document Feeder), and a document image scanning device 12 (scanner).

The automatic document feeder 11 transports the document D placed on the document tray using a transport mechanism and sends it to the document image scanning device 12. The automatic document feeder 11 can continuously read the images (including both sides) of multiple documents D placed on the document tray all at once.

The document image scanning device 12 optically scans the document transported from the automatic document feeder 11 onto the contact glass or the document placed on the contact glass, and forms an image of the reflected light from the document on a CCD (Charge Coupled Device) sensor 12a to read the document image. The image reading unit 10 generates input image data based on the results of the reading by the document image scanning device 12. This input image data is subjected to a predetermined image processing in the image processing unit 30.

The operation display unit 20 is, for example, a liquid crystal display (LCD) with a touch panel, and functions as a display unit 21 and an operation unit 22 (see FIG. 2). The display unit 21 displays various operation screens, image status displays, and the operating status of each function according to a display control signal input from the control unit 70 (see FIG. 2). The operation unit 22 has various operation keys such as a numeric keypad and a start key, and accepts various input operations by the user and outputs operation signals to the control unit 70.

The image processing unit 30 includes a circuit that performs image processing on input image data according to initial settings or user settings. The image forming unit 40 is controlled based on the image data that has been subjected to image processing.

The image forming section 40 includes image forming units 41Y, 41M, 41C, and 41K, and an intermediate transfer unit 42 for forming images using the color toners of the Y, M, C, and K components based on image data from the image processing section 30.

The image forming units 41Y, 41M, 41C, and 41K for the Y, M, C, and K components have the same configuration. Therefore, in FIG. 1, only the components of the image forming unit 41Y for the Y component are labeled, and the components of the other image forming units 41M, 41C, and 41K are not labeled.

The image forming unit 41 includes an exposure device 411, a developing device 412, a photosensitive drum 413 (image carrier), a charging device 414, a drum cleaning unit 415, etc.

The exposure device 411 is composed of, for example, a semiconductor laser, and irradiates the photoconductor drum 413 with laser light corresponding to an image of each color component. Positive charges are generated in the charge generation layer of the photoconductor drum 413 by irradiation with the laser light, and when the charges are transported to the surface of the charge transport layer, the surface charge (negative charge) of the photoconductor drum 413 is neutralized. As a result, an electrostatic latent image of each color component is formed on the surface of the photoconductor drum 413 due to the potential difference with the surroundings.

The developing device 412 is, for example, a two-component developing device having a developing sleeve 412A, and by depositing toner of each color component from the developing sleeve 412A onto the surface of the photoconductor drum 413, the electrostatic latent image is visualized to form a toner image.

The photoconductor drum 413 includes, for example, an aluminum conductive cylinder (aluminum tube), an undercoat layer (UCL), a charge generation layer (CGL), and a charge transport layer (CTL). The photoconductor drum 413 is a photoconductor having photoconductivity, which is configured by sequentially laminating an undercoat layer, a charge generation layer, and a charge transport layer on the circumferential surface of a conductive cylinder, and is, for example, a negatively charged organic photoconductor (OPC). The photoconductor drum 413 is rotated at a constant peripheral speed (linear speed) by the control unit 70 (see FIG. 2) controlling the drive current supplied to the drive motor (not shown).

The charging device 414 uniformly charges the surface of the photoconductive photoconductor drum 413 to a negative polarity.

The drum cleaning unit 415 includes a cleaning device 100, a lubricant supplying device 200, and the like (see FIG. 3, etc., described later). The drum cleaning unit 415 cleans the residual toner remaining on the surface of the photoconductor drum 413 and supplies a lubricant onto the photoconductor drum 413. The configuration of the drum cleaning unit 415 will be described later with reference to FIGS. 3 to 7.

The intermediate transfer unit 42 includes an intermediate transfer belt 421, a primary transfer roller 422, a plurality of support rollers 423 including a drive roller 423A and a backup roller 423B, a secondary transfer roller 424, a belt cleaning device 426, etc.

The intermediate transfer belt 421 is stretched in a loop around multiple support rollers 423, and the intermediate transfer belt 421 runs at a constant speed in the direction of arrow A as the drive roller 423A rotates. The primary transfer roller 422 presses the intermediate transfer belt 421 against the photosensitive drum 413, thereby transferring the toner image from the photosensitive drum 413 to the intermediate transfer belt 421. The secondary transfer roller 424 is pressed against the backup roller 423B with the intermediate transfer belt 421 in between, thereby transferring the toner image from the intermediate transfer belt 421 to the paper P. The paper P to which the toner image has been transferred is transported toward the fixing unit 60. Note that instead of the secondary transfer roller 424, a belt-type secondary transfer unit in which the secondary transfer belt is stretched in a loop around multiple support rollers may be used.

The belt cleaning device 426 has a belt cleaning blade that slides against the surface of the intermediate transfer belt 421 and removes residual toner remaining on the surface of the intermediate transfer belt 421 after the secondary transfer.

The paper transport section 50 includes a paper feed section 51, a paper discharge section 52, and a transport path section 53. The three paper feed tray units 51a to 51c that make up the paper feed section 51 store paper P (standard paper, special paper) identified based on basis weight, size, etc., by preset type. The transport path section 53 has multiple transport roller pairs, including a registration roller pair 53a.

The paper P stored in the paper feed tray units 51a to 51c is sent out one by one from the top and transported to the image forming section 40 by the transport path section 53. At this time, the inclination of the fed paper P is corrected and the transport timing is adjusted by the registration roller section in which the registration roller pair 53a is arranged. Then, the paper P on which an image has been formed through the image forming section 40 and the fixing section 60 is discharged outside the machine by the paper discharge section 52 equipped with the paper discharge roller 52a.

The fixing unit 60 heats and presses the transported paper P in a fixing nip, fixing the toner image to the paper P. The fixing unit 60 includes a fixing belt 61, a heating roller 62, a fixing roller 63, and a pressure roller 64. The fixing belt 61 is stretched between the heating roller 62 and the fixing roller 63. The pressure roller 64 forms a fixing nip between the fixing belt 61 and the paper P to sandwich and transport it.

The image forming device 1 also includes a control unit 70, as shown in FIG. 2.

The control unit 70 includes a CPU (Central Processing Unit) 71, a ROM (Read Only Memory) 72, and a RAM (Random Access Memory) 73. The CPU 71 reads a program corresponding to the processing contents from the ROM 72, loads it into the RAM 73, and centrally controls the operation of each block of the image forming device 1 in cooperation with the loaded program. At this time, various data such as a LUT (Look Up Table) stored in the memory unit 82 is referenced. The memory unit 82 is composed of, for example, a non-volatile semiconductor memory (so-called flash memory) or a hard disk drive.

The control unit 70 transmits and receives various data to and from an external device (e.g., a personal computer) connected to a communication network such as a LAN (Local Area Network) or a WAN (Wide Area Network) via the communication unit 81. The control unit 70 receives, for example, image data transmitted from an external device, and forms an image on paper based on this image data (input image data). The communication unit 81 is, for example, configured with a communication control card such as a LAN card.

The image reading unit 10, operation display unit 20, image processing unit 30, image forming unit 40, paper transport unit 50, and fixing unit 60 are each connected to the control unit 70. The control unit 70 is also connected to an air blower 91 and sound detection unit 92, which will be described later. These perform predetermined processing based on instructions from the control unit 70.

Here, the drum cleaning unit 415 will be described with reference to Figures 3 and 4. Figure 3 is a diagram showing the drum cleaning unit 415. Figure 4 is a diagram explaining the removal of the lubricant pressing mechanism 230 in the drum cleaning unit 415 shown in Figure 3.

The drum cleaning unit 415 includes a cleaning device 100, a lubricant supply device 200, etc. These are attached to and housed in a support frame 415a.

The cleaning device 100 includes a cleaning blade 101 and a supporting metal plate 102 to which the cleaning blade 101 is attached and supported. The width of the cleaning blade 101 and the supporting metal plate 102 is approximately equal to the width of the photoconductor drum 413 in the axial direction (main scanning direction). The cleaning blade 101 is a flat sheet made of an elastic material such as urethane rubber.

The cleaning blade 101 is configured as a counter type in which its tip (edge) is brought into contact with the photosensitive drum 413 in the rotation direction R1 opposite the photosensitive drum 413. Specifically, the cleaning blade 101 is arranged so that it comes into sliding contact with the photosensitive drum 413 in the counter direction in which the edge is pushed out, at a predetermined contact angle and penetration amount. With this configuration, the cleaning blade 101 comes into sliding contact with the surface of the photosensitive drum 413, and removes the residual toner remaining on the surface of the photosensitive drum 413 after the primary transfer.

The lubricant supplying device 200 includes an application brush 210, a fixing device 220, and a lubricant pressing mechanism 230 having a lubricant 231. Here, as an example of a lubricant application method, a downstream application system in which the lubricant supplying device 200 is disposed downstream of the cleaning device 100 in the rotation direction R1 of the photoconductor drum 413 is exemplified. Note that an upstream application system in which the lubricant supplying device 200 is disposed upstream of the cleaning device 100 may also be used.

The application brush 210 has the role of supplying the lubricant 231 onto the photoconductor drum 413. The application brush 210 is, for example, a roller-shaped brush in which a base cloth with fibers such as polyester woven therein is wound around a core metal, and has a width approximately equal to the axial width of the photoconductor drum 413. The application brush 210 is arranged so as to contact the surface of the lubricant 231 and the surface of the photoconductor drum 413, and rotates in a rotation direction R2 opposite to the rotation direction R1 of the photoconductor drum 413 to supply the lubricant onto the photoconductor drum 413. Note that although the application brush 210 is exemplified here as a lubricant application member that applies the lubricant 231, a lubricant application member made of a foam may also be used.

The fixing device 220 is disposed downstream of the application brush 210 in the rotation direction R1 of the photosensitive drum 413. The fixing device 220 includes a fixing blade 221, a support plate 222 to which the fixing blade 221 is attached and supported, and the like. The width of the fixing blade 221 and the support plate 222 is approximately equal to the axial width of the photosensitive drum 413. The material of the fixing blade 221 is a flat sheet made of an elastic member such as urethane rubber, similar to the cleaning blade 101.

The fixed blade 221 is configured as a trail type in which its tip (edge) is brought into contact with the photosensitive drum 413 along the rotation direction R1. Specifically, the fixed blade 221 is arranged so that it comes into sliding contact with the photosensitive drum 413 in the rotation direction R1 at a predetermined contact angle and penetration amount from the trail direction, which is the direction in which the edge is dragged. With this configuration, the fixed blade 221 comes into sliding contact with the surface of the photosensitive drum 413, and evens out and fixes the lubricant supplied onto the photosensitive drum 413 by the application brush 210.

In the lubricant pressing mechanism 230, the lubricant 231 is a lubricant solidified and molded into a rod shape. The width of the lubricant 231 in the axial direction of the photoconductor drum 413 is narrower than the width of the cleaning blade 101 and the fixed blade 221. The lubricant 231 has a hardness equivalent to F to HB on the pencil hardness scale, for example. The lubricant used for the lubricant 231 is, for example, zinc stearate (ZnSt).

The lubricant pressing mechanism 230 having such lubricant 231 is removably held by a holding member 201 attached to the support frame 415a. The lubricant pressing mechanism 230 held by the holding member 201 presses the lubricant 231 toward the application brush 210 with a predetermined pressing force in order to keep the lubricant 231 in contact with the application brush 210.

Since the lubricant pressing mechanism 230 is detachably held in the holding member 201, when replacing the lubricant 231, the currently used lubricant pressing mechanism 230 is removed from the holding member 201, and a new lubricant pressing mechanism 230 is attached to the holding member 201. Note that the lubricant 231 in the lubricant pressing mechanism 230 may be configured to be replaceable, and the lubricant 231 of the removed lubricant pressing mechanism 230 may be replaced with new lubricant 231 before being attached to the holding member 201.

The lubricant pressing mechanism 230 will be described with reference to Figs. 5 to 7. Fig. 5 is a view of the lubricant pressing mechanism 230 disassembled into the lubricant 231 side and the storage section 236 side. Fig. 6 is a view showing the internal state of the lubricant pressing mechanism 230 at the beginning of use of the lubricant 231. Fig. 7 is a view showing the internal state of the lubricant pressing mechanism 230 at the end of use of the lubricant 231.

The lubricant pressing mechanism 230 includes a rod-shaped lubricant 231, a support metal plate 232, a holding portion 233, a protrusion 234, a pressure spring 235, a storage portion 236, a guide groove 237, and the like. The lubricant 231 is supported on the support metal plate 232. The support metal plate 232 has a holding portion 233 at both ends in the longitudinal direction of the support metal plate 232, opposite the side on which the lubricant 231 is supported. The holding portion 233 has a protrusion 234 on the side facing outward in the longitudinal direction. The holding portion 233 has a pressure spring 235 on the side opposite the side on which the lubricant 231 is supported.

As shown in FIG. 5, the lubricant 231, the supporting metal plate 232, the holding portion 233, the protrusion portion 234, and the pressure spring 235 are attached integrally and housed inside the housing portion 236. The housing portion 236 is a rectangular parallelepiped container with one surface side being the insertion opening 236a. In the housing portion 236, a guide groove 237 is provided on the inner side surface in the longitudinal direction, and the guide groove 237 is formed in the depth direction of the housing portion 236.

When the lubricant 231 side is accommodated in the accommodation portion 236, the protrusion 234 is inserted into the guide groove 237 and is supported so as to be movable along the guide groove 237. Also, as shown in Figures 6 and 7, the pressure spring 235 comes into contact with the bottom 236b of the accommodation portion 236. In other words, the pressure spring 235 presses the lubricant 231 against the application brush 210 side (the upper side in Figures 6 and 7) via the support metal plate 232 and the holding portion 233.

Therefore, even if the lubricant 231 is scraped off by the application brush 210 and the remaining amount (height) of the lubricant 231 decreases, the pressure of the pressure spring 235 pushes up the support plate 232, so that the lubricant 231 can be maintained in contact with the application brush 210.

The lubricant 231 supplied onto the photoconductor drum 413 is a consumable item. Therefore, when the lubricant 231 runs out, for example, the frictional force between the photoconductor drum 413 and the cleaning blade 101 increases, which may result in the end of the life of the cleaning device. Specifically, poor cleaning of the residual toner on the photoconductor drum 413 may occur, or toner filming may occur on the photoconductor drum 413. As a result, the drum cleaning unit 415 may no longer be able to be used continuously.

Therefore, it is necessary to replace the lubricant before it runs out, and in a configuration in which the lubricant is replaced, it is desirable to accurately grasp the remaining amount of lubricant currently being used.

Therefore, in this embodiment, the image forming apparatus 1 is equipped with a lubricant remaining amount estimation device. The lubricant remaining amount estimation device includes a lubricant 231 supplied to the photoconductor drum 413, a resonance sound generation unit that generates different resonance sounds according to changes in the remaining amount of the lubricant 231, and a remaining amount estimation unit that estimates the remaining amount of the lubricant 231 based on the generated resonance sounds.

The resonance sound generating section will be described with reference to Figures 6 and 7. In the lubricant pressing mechanism 230, a space SP is formed between the support metal plate 232 and the bottom 236b. As described above, when the lubricant 231 is consumed and the remaining amount (height) of the lubricant decreases, the pressing spring 235 pushes up the support metal plate 232, widening the gap between the support metal plate 232 and the bottom 236b and increasing the volume of the space SP.

For example, in the early stages of use of the lubricant 231, as shown in FIG. 6, the height of the lubricant 231 is H1, and the gap between the support metal plate 232 and the bottom 236b is G1. As the lubricant 231 is consumed, the height of the lubricant decreases, and for example, at the end of the use of the lubricant 231, the height of the lubricant 231 becomes H2 (< H1) as shown in FIG. 7. As the height of the lubricant 231 decreases, the pressure spring 235 pushes up the support metal plate 232, and the above gap widens, and for example, at the end of the use of the lubricant 231, the above gap becomes G2 (> G1) as shown in FIG. 7.

In this way, the volume of the space SP changes depending on the remaining amount of lubricant 231. In this embodiment, an air vent (see FIG. 8, etc.), which will be described later, is provided in the storage section 236 that forms this space SP. In this configuration, when a certain amount of air is introduced into the air vent, the air in the space SP resonates, generating a sound, i.e., a resonance sound. The pitch of the generated resonance sound changes depending on the volume of the space SP. In other words, this embodiment has an air vent and the space SP as the resonance sound generating section, and the pitch of the resonance sound changes in the space SP depending on its volume.

The remaining amount estimation unit is provided as one of the functions of the control unit 70 (see FIG. 2). For example, the remaining amount estimation unit is provided as a program executed by the control unit 70. The resonance sound generated in the space SP of the resonance sound generating unit is used by the control unit 70, which functions as a remaining amount estimation unit, to estimate the remaining amount of lubricant 231. The method of estimating the remaining amount of lubricant 231 will be described later with reference to FIG. 9 and FIG. 10.

Below, we will explain some example configurations of a lubricant remaining amount estimation device.

[Configuration Example 1]
8 is a diagram showing a remaining lubricant amount estimation device of this configuration example. In this configuration example, the remaining lubricant amount estimation device includes a lubricant 231, a resonance sound generating unit, and a remaining amount estimation unit (control unit 70). The remaining lubricant amount estimation device also includes an air blower 91 that blows air to the resonance sound generating unit, and a sound detector 92 that detects the resonance sound generated by the resonance sound generating unit.

The resonance generating section has a space SP1 formed inside the storage section 236 by the two side sections 236c, the supporting metal plate 232, and the two barrier members 242. The barrier members 242 are provided between the two side sections 236c of the storage section 236 and between the supporting metal plate 232 and the bottom section 236b. Note that in FIG. 8, in order to show the inside of the storage section 236, only the side section 236c on the near side in the figure is illustrated. Also, in FIG. 8, the space SP1 is formed in two places inside the storage section 236.

The resonance generating section also has an air vent 241 (opening) formed in the bottom 236b of the storage section 236. In FIG. 8, the storage section 236 has two air vents 241 on the bottom 236b, which is one end in the direction in which the remaining amount of lubricant 231 changes, and each of the air vents 241 communicates with the space SP1.

The barrier member 242 is deformable, and is formed from, for example, a compressible or flexible material such as foam. For example, as shown in FIG. 6, in the early stages of use of the lubricant 231, the gap G1 between the support metal plate 232 and the bottom 236b is narrow, so the barrier member 242 compresses. Also, as shown in FIG. 7, in the final stages of use of the lubricant 231, the gap G2 between the support metal plate 232 and the bottom 236b is wide, so the barrier member 242 expands and tries to return to its original shape. In this way, the barrier member 242 compresses or expands as the support metal plate 232 moves, and its shape is deformed.

The volume of the space SP1 formed by the two side portions 236c, the support metal plate 232, and the two barrier members 242 changes as the support metal plate 232 moves with changes in the remaining amount of lubricant 231. In this configuration, when a certain amount of air is introduced into the ventilation hole 241, the air in the space SP1 resonates, generating a resonance sound, and the pitch of the generated resonance sound changes with the volume of the space SP1. In other words, this configuration example has the ventilation hole 241 and the space SP1 as the resonance sound generating part, and the pitch of the resonance sound changes in the space SP1 according to its volume.

The blower 91 blows air toward the ventilation opening 241, thereby drawing air into the space SP1 and generating a resonant sound. For example, a blower fan is used as the blower 91. In FIG. 8, the thick arrows indicate the flow path of the air blown into the space SP1.

The sound detection unit 92 detects the resonance sound that is generated in the space SP1 and output to the outside of the storage unit 236 through the ventilation opening 241, and inputs a sound signal of the detected resonance sound to the control unit 70. As the sound detection unit 92, for example, a sound collecting microphone is used.

The control unit 70 then estimates the remaining amount of lubricant 231 based on the sound signal input from the sound detection unit 92. For example, the control unit 70 detects a peak frequency from the sound signal detected by the sound detection unit 92, and estimates the remaining amount of lubricant 231 based on the peak frequency. In this case, a frequency detection device may be provided that detects the peak frequency from the sound signal detected by the sound detection unit 92, and the peak frequency may be input from the frequency detection device to the control unit 70.

Here, a method for estimating the remaining amount of lubricant 231 (lubricant remaining amount estimation method) will be described with reference to Figures 9 and 10. Figure 9 is a graph showing the relationship between the flow path width of the resonance sound generating part and the peak frequency of the resonance sound in the lubricant remaining amount estimation device shown in Figure 8. Figure 10 is a graph showing the relationship between the peak frequency of the resonance sound and the height of the lubricant in the lubricant remaining amount estimation device shown in Figure 8. Note that the flow path width of the resonance sound generating part, as explained with reference to Figure 8, refers to the distance between the support metal plate 232 and the ventilation hole 241.

In this configuration example, the remaining amount of lubricant is estimated based on the resonance sound generated in the resonance sound generating unit in response to changes in the remaining amount of lubricant 231.

Specifically, the support metal plate 232 moves according to the height (remaining amount) of the lubricant 231, and the flow path width between the support metal plate 232 and the ventilation hole 241 changes. When the flow path width changes, the pitch of the resonance sound generated in the resonance sound generating section also changes. In the lubricant remaining amount estimation device shown in Figure 8, the flow path width is changed, and the peak frequency of the resonance sound is detected as the pitch of the generated resonance sound, and this is graphed in Figure 9.

As shown in Figure 9, the peak frequency of the resonance sound decreases as the flow path width increases. In Figure 9, the flow path width of 2 mm is the flow path width at the beginning of use of the lubricant 231. Since the lubricant height at the beginning of use of the lubricant 231 is 10 mm, the flow path width when the lubricant 231 runs out is 12 mm.

Then, since the flow path width increases as the height (remaining amount) of the lubricant 231 decreases, the relationship shown in FIG. 9 can be converted to the relationship between the peak frequency of the resonance sound and the height of the lubricant shown in FIG. 10. As shown in FIG. 10, the height of the lubricant 231, i.e., the remaining amount, can be estimated based on the peak frequency of the resonance sound generated in the resonance sound generating unit. For example, the height (remaining amount) of the lubricant 231 can be estimated by finding an approximation formula from the graph shown in FIG. 10 and substituting the peak frequency of the resonance sound into the found approximation formula. When the lubricant height derived by the approximation formula is 0 mm, the lubricant 231 is in a depleted state and the lubricant 231 will reach the end of its life. In FIG. 10, the lubricant height of 10 mm is the lubricant height at the beginning of use of the lubricant 231, and the lubricant height of 0 mm is the lubricant height when the lubricant 231 is depleted.

The lubricant remaining amount estimation device may use, for example, the operation display unit 20 (notification unit) shown in FIG. 2 to notify information about the remaining amount of lubricant 231 according to the estimated remaining amount. For example, a lubricant height at which a notification is issued to prompt the user to replace the lubricant pressing mechanism 230 before the lubricant 231 runs out is determined in advance, and when the lubricant height is reached, the operation display unit 20 issues a notification to prompt the user to replace the lubricant pressing mechanism 230. For example, in FIG. 10, when the lubricant height reaches 0.5 mm, the operation display unit 20 issues a notification to prompt the user to replace the lubricant pressing mechanism 230. The operation display unit 20 may also notify a numerical value indicating the life of the lubricant 231 based on the estimated remaining amount of lubricant 231, for example, a numerical value indicating the remaining amount in %, with the initial amount being 100%.

As described above, in this configuration example, the lubricant remaining amount estimation device includes lubricant 231 that is supplied to the photoconductor drum 413. The lubricant remaining amount estimation device also includes a resonance sound generation unit that generates different resonance sounds in response to changes in the remaining amount of lubricant 231, and a remaining amount estimation unit (control unit 70) that estimates the remaining amount of lubricant 231 based on the generated resonance sounds.

According to this configuration example, the lubricant remaining amount estimation device estimates the remaining amount of lubricant 231 based on the resonance sound generated in the resonance sound generating section, whose volume changes according to the change in the remaining amount of lubricant 231, so that the remaining amount of lubricant 231 can be accurately estimated. As a result, it becomes possible to predict the lifespan of lubricant 231 with high accuracy.

In addition, this configuration example uses a resonance sound generating unit whose volume changes in response to changes in the remaining amount of lubricant 231, and this resonance sound generating unit is not affected by toner or lubricant powder. Therefore, toner and lubricant powder do not affect the estimation of the remaining amount of lubricant 231, and the remaining amount of lubricant 231 can be accurately estimated.

In the above-mentioned Patent Document 1, whether the lubricant has been depleted is determined by the electrical continuity between the electrode on the brush side and the electrode on the lubricant side, so it is not possible to detect how much lubricant remains. In contrast, in this configuration example, the remaining amount of lubricant 231 is estimated based on the resonance sound generated in the resonance sound generating section, whose volume changes according to changes in the remaining amount of lubricant 231, so the remaining amount of lubricant 231 can be checked at any time.

In FIG. 8, two spaces SP1 are formed, but the number of spaces in the resonance sound generating section may be one or three or more. When one space is formed, the space SP1 can be formed with two side parts 236c, the supporting metal plate 232, one side part 236d, and one barrier member 242, so there may be only one barrier member 242 and one ventilation hole 241, simplifying the configuration. When multiple spaces are formed, the remaining amount of lubricant 231 can be more accurately estimated by statistically processing (e.g., averaging) the peak frequency of the resonance sound generated in each space.

[Configuration Example 2]
11 is a diagram showing the remaining lubricant amount estimating device of this configuration example. In order to show the inside of the storage section 236, the side section 236c on the near side in the drawing is also omitted in FIG.

In the above configuration example 1, the space SP1 inside the storage unit 236 was used as the space of the resonance sound generating unit whose volume changes. In contrast, the present configuration example is basically the same as configuration example 1, but uses a space provided outside the storage unit 236 (space SP2, described later) as the space of the resonance sound generating unit whose volume changes.

Specifically, a box-shaped housing 243 having an air vent 243a (opening) is provided on the outside of a side 236d on one side (the right side in FIG. 11) of the storage section 236. The air vent 243a is provided on the same side of the housing 243 as the bottom 236b of the storage section 236, that is, on one end side in the direction in which the remaining amount of lubricant 231 changes, and is connected to the space SP2.

The support metal plate 232 is provided with an extension 232a extending from one end of the support metal plate 232. The extension 232a extends from one side 236d of the storage section 236 into the interior of the housing 243, and is configured to be movable within the housing 243 as the support metal plate 232 moves.

The volume of the space SP2 formed by the extension 232a and the housing 243 changes with the movement of the support metal plate 232 and the extension 232a as the remaining amount of lubricant 231 changes. In this configuration, when a certain amount of air is introduced into the vent 243a, the air in the space SP2 resonates, generating a resonance sound, and the pitch of the generated resonance sound changes with the volume of the space SP2. In other words, this configuration example has the vent 243a and the space SP2 as the resonance sound generating part, and the pitch of the resonance sound changes in the space SP2 according to its volume.

The blower 91 is arranged to blow air toward the ventilation opening 243a of the resonance sound generating section configured in this way. In FIG. 11, the thick arrows indicate the flow path of the air blown into the space SP2. Also, the sound detector 92 is arranged to detect the resonance sound generated in the space SP2 and output to the outside of the storage section 236 via the ventilation opening 243a.

Then, the control unit 70 estimates the remaining amount of lubricant 231 based on the sound signal input from the sound detection unit 92. For example, similar to configuration example 1, the control unit 70 detects a peak frequency from the sound signal detected by the sound detection unit 92, and estimates the remaining amount of lubricant 231 based on the peak frequency.

As described above, in this configuration example, the lubricant remaining amount estimation device also includes a lubricant 231 that is supplied to the photoconductor drum 413. The lubricant remaining amount estimation device also includes a resonance sound generation unit that generates different resonance sounds in response to changes in the remaining amount of lubricant 231, and a remaining amount estimation unit (control unit 70) that estimates the remaining amount of lubricant 231 based on the generated resonance sounds.

According to this configuration example configured in this manner, it is possible to obtain the same effect as configuration example 1. In addition, since the space SP2 of the resonance sound generating part is provided outside the storage part 236, it is possible to provide the space of the resonance sound generating part even in cases where it is difficult to provide the space of the resonance sound generating part inside the storage part 236.

[Configuration Example 3]
12 is a diagram showing the remaining lubricant amount estimating device of this configuration example. In order to show the inside of the storage section 236, the side section 236c on the near side in the drawing is also omitted in FIG.

In the above configuration example 1, a part of the space SP1 of the space SP (see Figures 6 and 7) inside the storage unit 236 was used as the space of the resonance sound generating unit whose volume changes. In contrast, the present configuration example is basically the same as configuration example 1, but the space SP inside the storage unit 236 is separated into multiple sub-spaces, and the state of communication between the separated sub-spaces is changed so that it can be used as the space of the resonance sound generating unit whose volume changes.

Specifically, an air vent 244 (opening) is provided in side 236d on one side (the right side in FIG. 11) of storage section 236. In this way, in storage section 236, air vent 244 is provided in side 236d, which is one end in a direction intersecting with the direction in which the remaining amount of lubricant 231 changes, and air vent 244 is connected to space SP. Note that here, the intersecting direction is the longitudinal direction of storage section 236.

In addition, multiple barrier members 251-255 in the shape of a rectangular prism are provided between the two side portions 236c of the storage portion 236 and between the support metal plate 232 and the bottom portion 236b. The barrier members 251-255 are arranged at different positions in the longitudinal direction inside the storage portion 236. The space portion SP formed by the support metal plate 232, the bottom portion 236b, the two side portions 236c, and the two side portions 236d is separated into multiple sub-space portions SPa-SPf in the longitudinal direction of the storage portion 236 by the barrier members 251-255 arranged as described above.

The barrier members 251-255 also have through holes 251a-255a (communication sections) that can connect the adjacent sub-spaces SPa-SPf, respectively. The through holes 251a-255a are provided to penetrate the barrier members 251-255 in the longitudinal direction of the storage section 236. The positions of the through holes 251a-255a of the barrier members 251-255 are different in the direction in which the remaining amount of lubricant 231 changes. Specifically, the distances of the through holes 251a-255a from the bottom 236b of the barrier members 251-255 are different, and the closer to the vent 244 the longer the distance from the lubricant 231, and the farther from the vent 244 the shorter the distance from the lubricant 231.

The barrier members 251-255 are deformable and are formed, for example, from a compressible or flexible material such as foam. Therefore, the barrier members 251-255 are compressed or expanded as the support metal plate 232 moves, and their shapes are deformed. The through holes 251a-255a are configured to open and close sequentially in the longitudinal direction as the barrier members 251-255 are deformed as the support metal plate 232 moves.

For example, in the early stages of use of the lubricant 231, the gap G1 between the support metal plate 232 and the bottom 236b is narrow (see FIG. 6), so the barrier members 251-255 are compressed and the through holes 251a-255a are closed. At this time, the barrier member 251 becomes the closed end, and the resonant sound generated in the subspace SPa that communicates with the ventilation hole 244 is detected.

As the lubricant 231 is consumed, the height of the lubricant decreases, and the pressure spring 235 pushes up the support metal plate 232, widening the gap between the support metal plate 232 and the bottom 236b. When the gap between the support metal plate 232 and the bottom 236b widens, the barrier members 251-255 expand, and first the through hole 251a of the barrier member 251 closest to the vent 244 opens, connecting the subspace SPa and the subspace SPb. At this time, the barrier member 252 becomes the closed end, and the resonant sound generated in the subspace SPa and the subspace SPb that are connected to the vent 244 is detected.

When the gap between the support metal plate 232 and the bottom 236b widens further, the barrier members 251-255 expand further, and the through hole 252a of the barrier member 252, which is the next closest to the vent 244 after the barrier member 251, opens, connecting the subspaces SPb and SPc. At this time, the barrier member 253 becomes the closed end, and the resonant sound generated in the subspaces SPa-SPc that communicate with the vent 244 is detected.

As the gap between the support metal plate 232 and the bottom 236b widens, the barrier members 251-255 expand further, the through holes 253a-255a of the barrier members 253-255 open in sequence, and the subspaces SPc-SPf communicate in sequence. At this time, the barrier members 254, 255 and the left side 236d in FIG. 12 become closed ends in sequence, and the subspaces SPa-SPf on the vent 244 side from the closed ends communicate with the vent 244. Then, among the subspaces SPa-SPf, the resonant sound generated in the subspaces communicating with the vent 244 (hereinafter, the communicating subspaces) is detected.

In this way, inside the storage section 236, as the lubricant 231 is consumed, the gap between the support metal plate 232 and the bottom 236b widens. In this configuration example, as the gap between the support metal plate 232 and the bottom 236b widens, the subspaces SPa to SPf are sequentially connected. In other words, as the remaining amount of lubricant 231 decreases, the subspaces SPa to SPf are sequentially connected starting from the subspace closest to the vent 244. In this way, the volume of the connected subspaces can be monotonically increased. Also, the distance from the vent 244 to the closed end (the barrier members 251 to 255 with the through holes 251a to 255a closed) can be changed.

In this way, as the support metal plate 232 moves, i.e., as the amount of lubricant 231 remains, the state of communication between the subspaces SPa to SPf changes, and the volume of the communicating subspaces changes. In this configuration, when a certain amount of air is introduced into the ventilation hole 244, the air in the communicating subspace that communicates with the ventilation hole 244 resonates, generating a resonance sound with a pitch that corresponds to the volume. In other words, this configuration example has the ventilation hole 244 and the subspaces SPa to SPf as resonance sound generating parts, and the pitch of the resonance sound changes in the subspaces SPa to SPf depending on the volume when they communicate with each other.

The blower 91 is arranged to blow air toward the ventilation opening 244 of the resonance sound generating section configured as described above. In addition, the sound detector 92 is arranged to detect the resonance sound generated in the communicating sub-space and output to the outside of the storage section 236 via the ventilation opening 244.

Then, the control unit 70 estimates the remaining amount of lubricant 231 based on the sound signal input from the sound detection unit 92. For example, similar to configuration example 1, the control unit 70 detects a peak frequency from the sound signal detected by the sound detection unit 92, and estimates the remaining amount of lubricant 231 based on the peak frequency.

Here, we will explain how to estimate the remaining amount of lubricant 231 in this configuration example with reference to Figures 13 to 15.

Figure 13 is a graph showing the relationship between the height of the lubricant 231 and the flow path width of the resonance sound generating section in the lubricant remaining amount estimation device shown in Figure 12. In Figure 13, the lubricant is considered to be depleted when the lubricant height is 0.5 mm.

As shown in FIG. 13, in this configuration example, the flow path width of the resonance sound generating section changes in stages as the height of the lubricant 231 changes. This is because the barrier members 251-255 are made of a compressible and deformable material, and the through holes 251a-255a do not go from a closed state to an open state unless the compressed barrier members 251-255 are stretched to a predetermined length or more.

In FIG. 13, the case where the height of the lubricant 231 is reduced from approximately 9.2 mm to approximately 6.7 mm, that is, the case of the barrier member 251, will be described as an example. When the height of the lubricant 231 is reduced from approximately 9.2 mm to approximately 6.7 mm, the support plate 232 is pushed up by the pressure spring 235 as the height of the lubricant 231 is reduced (see FIG. 12).

When the support metal plate 232 is pushed up, the compressed barrier member 251 expands, but the length of expansion is shorter than the predetermined length by which the through hole 251a changes from a closed state to an open state. Therefore, the through hole 251a maintains a closed state. Therefore, within the range of the height of the lubricant 231 where the through hole 251a maintains a closed state, the flow path width of the resonance sound generating section, that is, the distance from the vent 244 to the closed end, is the distance from the vent 244 to the barrier member 251, which is 50 mm as shown in FIG. 13.

When the height of the lubricant 231 decreases below approximately 6.7 mm, the through hole 251a opens, and the flow path width of the resonance sound generating section, that is, the distance from the vent 244 to the closed end, becomes the distance from the vent 244 to the barrier member 252, which is 100 mm as shown in Figure 13.

As shown in FIG. 13, the barrier members 252 to 255 are similar to the barrier member 251. For example, in the case of the barrier member 252, within the range of the height of the lubricant 231 where the through hole 252a is kept closed, the flow path width of the resonance sound generating section, that is, the distance from the vent 244 to the closed end, is the distance from the vent 244 to the barrier member 252.

Figure 14 is a graph showing the relationship between the flow path width of the resonance sound generating section and the peak frequency of the resonance sound in the lubricant remaining amount estimation device shown in Figure 12. Figure 15 is a graph showing the relationship between the peak frequency of the resonance sound and the height of the lubricant in the lubricant remaining amount estimation device shown in Figure 12. Note that the flow path width of the resonance sound generating section, as explained with reference to Figure 12, refers to the distance between the vent 241 and the closed end (barrier members 251-255 with through holes 251a-255a closed).

As described above, the support metal plate 232 moves depending on the level (remaining amount) of lubricant, and as the support metal plate 232 moves, the barrier members 251-255 that form the closed ends also change, and the flow path width between the vent 244 and the barrier members 251-255 that form the closed ends also changes. When this flow path width changes, the pitch of the resonance sound generated in the resonance sound generating section also changes.

In the lubricant remaining amount estimation device shown in Figure 12, the barrier members 251-255 that serve as the closed ends are changed to change the flow path width, and the peak frequency of the resonance sound is detected as the pitch of the resonance sound, which is graphed in Figure 14. As shown in Figure 14, it can be seen that the peak frequency of the resonance sound decreases as the flow path width increases.

Then, the relationship shown in Figures 13 and 14 can be converted into the relationship between the peak frequency of the resonance sound and the height of the lubricant shown in Figure 15. As shown in Figure 15, the height of the lubricant 231, i.e., the remaining amount, can be estimated based on the peak frequency of the resonance sound generated in the resonance sound generating unit.

For example, if the peak frequency of the resonance sound generated by the resonance sound generating unit is 484 Hz, the lubricant height can be estimated to be 3.3 to 6.6 mm from FIG. 15. In this case, if the height of the lubricant 231 at the beginning of use is 10 mm, the remaining amount of lubricant 231 is 33 to 66%, so the control unit 70 determines that there is a sufficient amount remaining and, for example, causes the operation display unit 20 to notify that the remaining amount is 33 to 66%.

For example, when the peak frequency of the resonance sound generated by the resonance sound generating unit is 264 Hz, the lubricant height can be estimated to be 0 to 0.8 mm from FIG. 15. In this case, if the height of the lubricant 231 at the beginning of use is 10 mm, the remaining amount of lubricant 231 is 0 to 0.8%, so the control unit 70 determines that the lubricant has not yet run out and, for example, causes the operation display unit 20 to issue an alert urging the user to replace the lubricant pressing mechanism 230. Note that in FIG. 15, the lubricant height when the lubricant 231 runs out is 0.5 mm.

As described above, in this configuration example, the lubricant remaining amount estimation device also includes a lubricant 231 that is supplied to the photoconductor drum 413. The lubricant remaining amount estimation device also includes a resonance sound generation unit that generates different resonance sounds in response to changes in the remaining amount of lubricant 231, and a remaining amount estimation unit (control unit 70) that estimates the remaining amount of lubricant 231 based on the generated resonance sounds.

This configuration example, configured in this way, can achieve the same effects as configuration example 1.

FIG. 16 shows a modified example of the lubricant remaining amount estimation device shown in FIG. 12. In FIG. 12, the barrier members 251 to 255 are rectangular prism shaped, but instead, as shown in FIG. 16, barrier members 261 to 265 having a trapezoidal cross section and a column shape may be used.

Barrier members 261-265 have a different shape from barrier members 251-255, but apart from the shape, they have the same configuration as barrier members 251-255. Barrier members 261-265 also have through holes 261a-265a (communication parts), which also have the same configuration as through holes 251a-255a.

In this modified example, the barrier members 261-265 are columnar with a trapezoidal cross section. Therefore, when the support metal plate 232 presses against the barrier members 261-265 to compress them, the direction in which the support metal plate 232 presses can be made the same as the direction in which the barrier members 261-265 compress. This ensures that the through holes 261a-265a in the barrier members 261-265 can be opened and closed.

In addition, in this configuration example, the more barrier members 251-255 and barrier members 261-265 there are, the more accurate the estimation of the remaining amount of lubricant 231 becomes, but the effect of this configuration example can be obtained even if there is only one barrier member.

[Configuration Example 4]
17 is a diagram showing the remaining lubricant amount estimating device of this configuration example. In order to show the inside of the storage section 236, the side section 236c on the near side in the drawing is also omitted in FIG.

In the above configuration example 3, barrier members 251-255 having through holes 251a-255a at different positions are used in the resonance sound generating section to change the distance from the vent 244 to the closed end in response to changes in the remaining amount of lubricant 231. This configuration example is basically the same as configuration example 3, but instead of barrier members 251-255 having through holes 251a-255a at different positions, barrier members 271-275 having different lengths are used.

Specifically, a plurality of barrier members 271-275 are provided between the two side portions 236c on the lower side of the support metal plate 232 (opposite the lubricant 231). The plurality of barrier members 271-275 are fixed to the lower side of the support metal plate 232, for example, by adhesive or the like. The barrier members 271-275 are arranged at different positions in the longitudinal direction of the support metal plate 232.

The barrier members 271 to 275 also have different lengths in the direction in which the remaining amount of lubricant 231 changes, being shorter the closer they are to the ventilation opening 244 and longer the farther they are from the ventilation opening 244.

The barrier members 271-275 are deformable and are formed from a compressible and deformable material, such as foam. Therefore, the barrier members 271-275 are compressed or expanded as the support metal plate 232 moves, and their shape is deformed. When the barrier members 271-275 are compressed, the space SP is separated into a plurality of sub-spaces SPa-SPf in the longitudinal direction of the storage section 236 by the barrier members 271-275 arranged as described above.

For example, when the lubricant 231 is first used, the gap G1 between the support metal plate 232 and the bottom 236b is narrow (see FIG. 6), so the barrier members 271 to 275 are compressed. At this time, the barrier member 271 becomes the closed end, and the resonant sound generated in the subspace SPa that communicates with the ventilation hole 244 is detected.

As the lubricant 231 is consumed, the height of the lubricant decreases, and the pressure spring 235 pushes up the support metal plate 232, widening the gap between the support metal plate 232 and the bottom 236b. When the gap between the support metal plate 232 and the bottom 236b widens, the barrier members 271 to 275 stretch, but first a gap (communication section) is created between the shortest barrier member 271 and the bottom 236b, and the subspaces SPa and SPb communicate with each other. At this time, the barrier member 272 becomes the closed end, and the resonant sound generated in the subspaces SPa and SPb that communicate with the ventilation opening 244 is detected.

When the gap between the support metal plate 232 and the bottom 236b widens further, the barrier members 272-275 stretch, but a gap (communication) is created between the barrier member 272, which is the second shortest after the barrier member 271, and the bottom 236b, and the subspaces SPb and SPc communicate with each other. At this time, the barrier member 273 becomes the closed end, and the resonant sound generated in the subspaces SPa-SPc that communicate with the vent 244 is detected.

As the gap between the support metal plate 232 and the bottom 236b widens, the barrier members 273-275 expand, and gaps (communicating sections) are successively formed between the barrier members 273-275 and the bottom 236b, and the subspaces SPc-SPf are successively connected. At this time, the barrier members 274, 275 and the left side section 236d in FIG. 17 successively become closed ends, and among the subspaces SPa-SPf, the subspaces on the vent 244 side from the closed ends communicate with the vent 244. Then, among the subspaces SPa-SPf, the resonant sound generated in the subspaces (communicating subspaces) that communicate with the vent 244 is detected.

Inside the storage section 236, as the lubricant 231 is consumed, the gap between the support metal plate 232 and the bottom 236b widens. In this configuration example, as the gap between the support metal plate 232 and the bottom 236b widens, the contact state between the barrier members 271-275 and the bottom 236b changes, and gaps (communication sections) are created between the barrier members 271-275 and the bottom 236b. And, as gaps (communication sections) are created between the barrier members 271-275 and the bottom 236b, the sub-spaces SPa-SPf are sequentially connected to each other.

Here, as the remaining amount of lubricant 231 decreases, the sub-spaces SPa to SPf are sequentially connected starting from the sub-space closest to the vent 244. In this way, the volume of the connected sub-spaces can be monotonically increased. Also, the distance from the vent 244 to the closed ends (barrier members 271 to 275) can be changed.

In this way, as the support metal plate 232 moves, i.e., as the amount of lubricant 231 remains, the state of communication between the subspaces SPa to SPf changes, and the volume of the communicating subspaces changes. In this configuration, when a certain amount of air is introduced into the ventilation hole 244, the air in the communicating subspace that communicates with the ventilation hole 244 resonates, generating a resonance sound with a pitch that corresponds to the volume. In other words, this configuration example also has the ventilation hole 244 and the subspaces SPa to SPf as resonance sound generating parts, and the pitch of the resonance sound changes in the subspaces SPa to SPf depending on the volume when they communicate with each other.

The blower 91 is arranged to blow air toward the ventilation opening 244 of the resonance sound generating section configured as described above. In addition, the sound detector 92 is arranged to detect the resonance sound generated in the communicating sub-space and output to the outside of the storage section 236 via the ventilation opening 244.

Then, the control unit 70 estimates the remaining amount of lubricant 231 based on the sound signal input from the sound detection unit 92. For example, similar to configuration example 1, the control unit 70 detects a peak frequency from the sound signal detected by the sound detection unit 92, and estimates the remaining amount of lubricant 231 based on the peak frequency.

As described above, in this configuration example, the lubricant remaining amount estimation device also includes a lubricant 231 that is supplied to the photoconductor drum 413. The lubricant remaining amount estimation device also includes a resonance sound generation unit that generates different resonance sounds in response to changes in the remaining amount of lubricant 231, and a remaining amount estimation unit (control unit 70) that estimates the remaining amount of lubricant 231 based on the generated resonance sounds.

This configuration example, configured in this way, can achieve the same effects as configuration example 1.

In FIG. 17, the barrier members 271 to 275 are provided on the lower side of the supporting metal plate 232, but the same effect can be obtained even if they are provided on the upper side of the bottom portion 236b.

[Configuration Example 5]
18 is a diagram showing the remaining lubricant amount estimating device of this configuration example. In order to show the inside of the storage section 236, the side section 236c on the near side in the drawing is also omitted in FIG.

In the above configuration example 4, barrier members 271-275 having different lengths are used in the resonance sound generating section to change the distance from the vent 244 to the closed end in response to changes in the remaining amount of lubricant 231. This configuration example is basically the same as configuration example 4, but instead of the barrier members 271-275, barrier members 281-285 made of different materials are used.

Specifically, the barrier members 281-285 are deformable and are formed, for example, from a PET film such as Mylar (registered trademark).

A number of barrier members 281-285 are provided between the two side portions 236c on the lower side of the support metal plate 232 (the side opposite the lubricant 231). The barrier members 281-285 are fixed to the lower side of the support metal plate 232, for example, with tape or adhesive. The barrier members 281-285 are arranged at different positions on the support metal plate 232 in the longitudinal direction.

The barrier members 281 to 285 also have different lengths in the direction in which the remaining amount of lubricant 231 changes, being shorter the closer they are to the ventilation opening 244 and longer the farther they are from the ventilation opening 244.

As described above, the barrier members 281-285 are made of PET film and are flexible. Therefore, the barrier members 281-285 change shape as the support metal plate 232 moves. When the barrier members 281-285 come into contact with the bottom 236b, the space SP is separated into multiple sub-spaces SPa-SPf in the longitudinal direction of the storage section 236 by the barrier members 281-285 arranged as described above.

For example, in the early stages of use of the lubricant 231, the gap G1 between the support metal plate 232 and the bottom 236b is narrow (see FIG. 6), so the barrier members 281-285 bend and come into contact with the bottom 236b. At this time, the barrier member 281 becomes the closed end, and the resonant sound generated in the subspace SPa that communicates with the vent 244 is detected.

As the lubricant 231 is consumed, the height of the lubricant decreases, and the pressure spring 235 pushes up the support metal plate 232, widening the gap between the support metal plate 232 and the bottom 236b. When the gap between the support metal plate 232 and the bottom 236b widens, the shortest barrier member 281 first returns to its original bending, creating a gap (communication) between the barrier member 281 and the bottom 236b, and the subspaces SPa and SPb communicate with each other. At this time, the barrier member 282 becomes the closed end, and the resonant sound generated in the subspaces SPa and SPb that communicate with the vent 244 is detected.

When the gap between the support metal plate 232 and the bottom 236b widens further, the deflection of the barrier member 282, which is the second shortest after the barrier member 281, returns to normal, creating a gap (communication) between the barrier member 282 and the bottom 236b, and the subspaces SPb and SPc communicate with each other. At this time, the barrier member 283 becomes the closed end, and the resonant sound generated in the subspaces SPa to SPc that communicate with the vent 244 is detected.

As the gap between the support metal plate 232 and the bottom 236b widens, the barrier members 283-285 gradually return to their original deflection, and gaps (communicating sections) are formed between the barrier members 283-285 and the bottom 236b, and the subspaces SPc-SPf gradually communicate with each other. At this time, the barrier members 284, 285 and the left side 236d in FIG. 18 gradually become closed ends, and the subspaces SPa-SPf that are closer to the vent 244 than the closed ends communicate with the vent 244. Then, the resonant sound generated in the subspaces (communicating subspaces) that communicate with the vent 244 is detected in the subspaces SPa-SPf.

Inside the storage section 236, as the lubricant 231 is consumed, the gap between the support metal plate 232 and the bottom 236b widens. In this configuration example, as the gap between the support metal plate 232 and the bottom 236b widens, the contact state between the barrier members 281-285 and the bottom 236b changes, and gaps (communication sections) are created between the barrier members 281-285 and the bottom 236b. And, as gaps (communication sections) are created between the barrier members 281-285 and the bottom 236b, the sub-spaces SPa-SPf are sequentially connected to each other.

In this case, as the remaining amount of lubricant 231 decreases, the sub-spaces SPa to SPf are sequentially connected starting from the sub-space closest to the vent 244. In this way, the volume of the connected sub-spaces can be monotonically increased. Also, the distance from the vent 244 to the closed ends (barrier members 281 to 285) can be changed.

In this way, as the support metal plate 232 moves, i.e., as the amount of lubricant 231 remains, the state of communication between the subspaces SPa to SPf changes, and the volume of the communicating subspaces changes. In this configuration, when a certain amount of air is introduced into the ventilation hole 244, the air in the communicating subspace that communicates with the ventilation hole 244 resonates, generating a resonance sound with a pitch that corresponds to the volume. In other words, this configuration example also has the ventilation hole 244 and the subspaces SPa to SPf as resonance sound generating parts, and the pitch of the resonance sound changes in the subspaces SPa to SPf depending on the volume when they communicate with each other.

The blower 91 is arranged to blow air toward the ventilation opening 244 of the resonance sound generating section configured as described above. In addition, the sound detector 92 is arranged to detect the resonance sound generated in the communicating sub-space and output to the outside of the storage section 236 via the ventilation opening 244.

Then, the control unit 70 estimates the remaining amount of lubricant 231 based on the sound signal input from the sound detection unit 92. For example, similar to configuration example 1, the control unit 70 detects a peak frequency from the sound signal detected by the sound detection unit 92, and estimates the remaining amount of lubricant 231 based on the peak frequency.

As described above, in this configuration example, the lubricant remaining amount estimation device also includes a lubricant 231 that is supplied to the photoconductor drum 413. The lubricant remaining amount estimation device also includes a resonance sound generation unit that generates different resonance sounds in response to changes in the remaining amount of lubricant 231, and a remaining amount estimation unit (control unit 70) that estimates the remaining amount of lubricant 231 based on the generated resonance sounds.

This configuration example, configured in this way, can achieve the same effects as configuration example 1.

[Configuration Example 6]
FIG. 19 is a diagram showing a lubricant supplying device 200 of this configuration example in the image forming apparatus 1. As shown in FIG.

This configuration example is premised on an image forming apparatus 1 having a lubricant remaining amount estimation device according to any one of configuration examples 1 to 5 above. In addition, in the image forming apparatus 1, the lubricant supply device 200 has a shaft 211, a bearing 212, a driven gear 213, a drive gear 214, a motor 215 as a drive source, a support member 216, etc., as shown in FIG. 19.

The shaft 211 is provided on both ends of the application brush 210 (supply member) and serves as the rotation axis of the application brush 210. The bearing 212 rotatably supports the shaft 211 and is provided on a support member 216. The driven gear 213 is provided on one end side of the shaft 211. The drive gear 214 is a gear that drives the driven gear 213. The motor 215 drives the drive gear 214. The support member 216 is provided on the outside of the side portion 236d of the storage portion 236.

As described in FIG. 3, the application brush 210 contacts the lubricant 231 and the photoconductor drum 413. As the application brush 210 rotates, it scrapes off lubricant powder from the lubricant 231 and supplies it to the photoconductor drum 413.

The above-mentioned shaft 211, bearing 212, driven gear 213, drive gear 214, and motor 215 constitute a drive mechanism that rotates and drives the application brush 210. Specifically, in accordance with a control signal from the control unit 70, the motor 215 rotates to rotate the drive gear 214, and the rotation of the drive gear 214 rotates the driven gear 213 and shaft 211, thereby rotating the application brush 210.

The amount of lubricant supplied from the application brush 210 to the photosensitive drum 413 is determined by the rotation speed of the application brush 210, the pressure of the lubricant 231 on the application brush 210, the amount of penetration of the application brush 210 into the photosensitive drum 413, etc.

When the lubricant 231 is pressed against the application brush 210 using the lubricant pressing force of the pressing spring 235, as the remaining amount of lubricant 231 decreases, the pressing spring 235 may stretch and the lubricant pressing force may decrease. When the lubricant pressing force decreases, the amount of lubricant supplied also decreases, increasing the frictional force between the photoconductor drum 413 and the cleaning blade 101. As a result, poor cleaning of the residual toner on the photoconductor drum 413 may occur, or toner filming may occur.

Therefore, in this configuration example, the rotation speed of the application brush 210 is increased to compensate for the decrease in the amount of lubricant supplied due to the decrease in the lubricant pressing force. Conventional image forming devices were unable to estimate the remaining amount of lubricant as in the present invention, and could only roughly predict the remaining amount based on the number of sheets of paper processed for image formation and the rotation time of the application brush 210.

In contrast, in this configuration example, the image forming apparatus 1 is equipped with a lubricant remaining amount estimation device according to any one of configuration examples 1 to 5 described above, and is therefore able to estimate the remaining amount of lubricant 231. The lubricant pressing force can then be calculated based on the estimated remaining amount of lubricant 231, and the rotational speed of the application brush 210 that maintains the amount of lubricant supplied can be calculated based on the calculated lubricant pressing force.

Figure 20 is a graph showing the relationship between the lubricant height and the rotational speed of the application brush 210. The control unit 70 can use the remaining amount of lubricant 231 estimated by the lubricant remaining amount estimation device of any of configuration examples 1 to 5 above to determine the rotational speed of the application brush 210 by referring to the graph shown in Figure 20. The control unit 70 can then rotate the application brush 210 at the determined rotational speed, thereby compensating for the decrease in the amount of lubricant supplied due to a decrease in the lubricant pressing force. In other words, even if the lubricant pressing force decreases, the target amount of lubricant supplied can be accurately maintained by increasing the rotational speed of the application brush 210.

In this way, the control unit 70 functions as a rotation speed change unit that changes the rotation speed at which the application brush 210 rotates depending on the estimated remaining amount of lubricant 231.

Next, a control method for a lubricant remaining amount estimation device including a lubricant remaining amount estimation method will be described with reference to FIG. 21. FIG. 21 is a flowchart illustrating a control method for a lubricant remaining amount estimation device including a lubricant remaining amount estimation method.

(Step S11)
The control unit 70 checks whether the image forming process is stopped. If the image forming process is stopped (YES), the process proceeds to step S12. If the image forming process is not stopped, the process repeats step S11 until the image forming process is stopped.

The lubricant remaining amount estimation device detects resonance sounds, so it is desirable to execute the process while the image formation process is stopped, when noise levels are low. Therefore, here we check whether the image formation process is stopped.

(Step S12)
The control unit 70 uses the blower 91 to introduce air into the storage unit 236 of the lubricant 231, and collects the resonance sound generated in the storage unit 236 with the sound detection unit 92. For example, referring to FIG. 12 , the control unit 70 uses the blower 91 to introduce air into the space SP1 from the ventilation hole 241 formed in the bottom 236b of the storage unit 236, and collects the resonance sound generated in the space SP1 with the sound detection unit 92.

(Step S13)
The control unit 70 detects the peak frequency of the resonance sound collected by the sound detection unit 92. At this time, the control unit 70 may detect the peak frequency of the resonance sound using a frequency detection device that detects the peak frequency of the resonance sound.

(Step S14)
Based on the peak frequency of the resonance sound, the control unit 70 estimates the remaining amount of lubricant 231. The control unit 70 may estimate the lubricant height, i.e., the remaining amount of lubricant 231, based on the peak frequency of the resonance sound, using, for example, the graph shown in Fig. 10 or an approximation thereof.

(Step S15)
Based on the estimated remaining amount of lubricant, the control unit 70 determines the number of rotations of the application brush 210. The control unit 70 may determine the number of rotations of the application brush 210 based on the lubricant height (remaining amount of lubricant 231) using, for example, the graph shown in Fig. 20 or an approximation thereof.

(Step S16)
The control unit 70 judges whether the estimated remaining amount of lubricant is equal to or less than a predetermined value. If the estimated remaining amount of lubricant is equal to or less than the predetermined value (YES), the process proceeds to step S17. If the estimated remaining amount of lubricant is not equal to or less than the predetermined value, that is, if the estimated remaining amount of lubricant exceeds the predetermined value, the series of controls ends.

(Step S17)
When the estimated remaining amount of lubricant is equal to or less than a predetermined value, the control unit 70 determines that the lubricant is about to run out and issues a notice to replace the lubricant. For example, the control unit 70 issues an alert using the operation display unit 20 to prompt the user to replace the lubricant 231 (lubricant pressing mechanism 230).

As described above, in this configuration example, the lubricant remaining amount estimation device includes an application brush 210 that rotates to supply lubricant 231 to the photoconductor drum 413. The lubricant remaining amount estimation device also includes a rotation speed change unit that changes the rotation speed at which the application brush 210 rotates depending on the estimated remaining amount of lubricant 231.

In this configuration example, the rotational speed of the application brush 210 is changed according to the estimated remaining amount of lubricant 231, so that the target amount of lubricant supplied can be accurately maintained.

In addition, in order to accurately maintain the target amount of lubricant supplied, a configuration (pressure change unit) may be used that changes the pressure with which the lubricant 231 is pressed against the application brush 210 according to the estimated remaining amount of lubricant 231. The pressure change unit has, for example, an actuator disposed between the pressure spring 235 and the bottom portion 236b, and can change the pressure with which the lubricant 231 is pressed against the application brush 210 by changing the expansion/contraction state of the pressure spring 235 using the actuator.

[Other configuration examples]
In the above configuration examples 1 to 6, the blower 91 for blowing air is used as the input source for generating the resonance sound. However, the input source may be anything capable of outputting sound, such as a speaker.

The above embodiments are merely examples of the implementation of the present invention, and the technical scope of the present invention should not be interpreted in a limiting manner. In other words, the present invention can be implemented in various forms without departing from its gist or main characteristics.

LIST OF SYMBOLS 1 Image forming apparatus 10 Image reading section 20 Operation display section 30 Image processing section 40 Image forming section 50 Paper conveying section 60 Fixing section 70 Control section 91 Air blowing section 92 Sound detection section 101 Cleaning blade 200 Lubricant supplying device 210 Application brush 221 Fixed blade 230 Lubricant pressing mechanism 231 Lubricant 232 Supporting plate 232a Extension section 235 Pressing spring 236 Storage section 241 Ventilation hole 242 Barrier member 243 Housing 243a Ventilation hole 244 Ventilation hole 251 to 255 Barrier member 251a to 255a Through hole 261 to 265 Barrier member 261a to 265a Through hole 271 to 275 Barrier member 281 to 285 Barrier members

Claims (18)

a resonance sound generating unit that generates different resonance sounds in response to a change in the remaining amount of lubricant supplied to the image carrier;
a remaining amount estimation unit that estimates the remaining amount of the lubricant based on the generated resonance sound;
A lubricant remaining amount estimation device comprising: The remaining amount estimation unit estimates the remaining amount of the lubricant based on a peak frequency of the resonance sound.
The lubricant remaining amount estimating device according to claim 1. a notification unit that notifies information regarding the remaining amount of the lubricant according to the estimated remaining amount of the lubricant;
The lubricant remaining amount estimating device according to claim 1 or 2. The resonance sound generating portion has a space portion whose volume changes with a change in the remaining amount of the lubricant.
The lubricant remaining amount estimating device according to any one of claims 1 to 3. A storage section for storing the lubricant is provided,
The space is formed between the lubricant and the storage portion.
The lubricant remaining amount estimating device according to claim 4. a deformable barrier member disposed between the lubricant and the container;
The space is formed by the lubricant, the storage portion, and the barrier member.
The lubricant remaining amount estimating device according to claim 5. the storage portion has an opening portion communicating with the space portion at one end in a direction in which the remaining amount of the lubricant changes,
The resonance generating unit outputs the resonance generated in the space to the outside of the storage unit through the opening.
The lubricant remaining amount estimating device according to claim 5 or 6. the storage portion has an opening portion communicating with the space portion at one end in a direction intersecting with a direction in which the remaining amount of the lubricant changes,
The resonance generating unit outputs the resonance generated in the space to the outside of the storage unit through the opening.
The lubricant remaining amount estimating device according to claim 5. A deformable barrier member is provided to separate the space in the cross direction to form a plurality of subspaces,
The barrier member has a communication portion that changes a communication state between adjacent sub-spaces to change the volume of the plurality of communicating sub-spaces.
The lubricant remaining amount estimating device according to claim 8. A plurality of the barrier members are provided,
The barrier members are arranged at different positions in the cross direction.
The lubricant remaining amount estimating device according to claim 9. the communication portions of the barrier members are arranged such that the volumes of the communicating sub-spaces increase as the remaining amount of the lubricant decreases.
The lubricant remaining amount estimating device according to claim 10. In a direction in which the remaining amount of the lubricant changes, the positions of the communication portions of the plurality of barrier members are different.
The lubricant remaining amount estimating device according to claim 11. The communication portion is a through hole that penetrates the barrier member in the intersecting direction and opens and closes in accordance with deformation of the barrier member.
The lubricant remaining amount estimating device according to any one of claims 9 to 12. The communication portion is a gap formed between the barrier member and the lubricant or the storage portion due to deformation of the barrier member.
The lubricant remaining amount estimating device according to any one of claims 9 to 12. a supply member that rotates to supply the lubricant to the image carrier;
a rotation speed change unit that changes a rotation speed at which the supply member is rotated in accordance with the estimated remaining amount of the lubricant;
Equipped with
The lubricant remaining amount estimating device according to any one of claims 1 to 14. a pressing force changing unit that changes a pressing force for pressing the lubricant against the supply member in accordance with the estimated remaining amount of the lubricant;
The lubricant remaining amount estimating device according to any one of claims 15 to 18. An image forming apparatus equipped with a lubricant remaining amount estimation device according to any one of claims 1 to 16. a remaining amount of lubricant supplied to an image carrier is estimated based on a resonance sound generated by a resonance sound generating unit which generates different resonance sounds according to a change in the remaining amount of the lubricant supplied to the image carrier;
A method for estimating remaining lubricant.

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