JP2010217766A - Image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image forming apparatus that stably removes adhering matter from the surface of an image holding body. <P>SOLUTION: The image forming apparatus includes: the image holding body for holding a toner image on its surface; an image forming section for forming a toner image on the surface of the image holding body; a transfer fixing section for transferring and fixing the toner image formed on the surface of the image holding body, to the surface of the recording medium; a cleaning member having a member body which is brought into contact with the surface of the image holding body and removes adhering matter from the surface, and a sensor which is brought into contact with the member body, and outputs a signal corresponding to distortion of the member body; and a toner supply section for supplying toner to the surface of the image holding body on the basis of the signal from the sensor. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an image forming apparatus.

  2. Description of the Related Art Conventionally, there is known an image forming apparatus that forms a toner image on an image holding member, transfers the toner image onto a recording medium, and fixes the toner image. Some of such image forming apparatuses include a cleaning blade that removes deposits on the image carrier.

  Patent Document 1 proposes a technique for providing a conductive layer on both the cleaning blade and the image carrier, and detecting the turning of the cleaning blade by contacting the conductive layer when the cleaning blade is turned up.

  Patent Document 2 proposes a technique for dynamically observing internal strain applied to the cleaning blade by a photoelastic method in a state where the cleaning blade is in contact with the image carrier.

  Further, Patent Document 3 proposes a technique for correcting the distortion of the cleaning blade by attracting a magnetic body attached to the cleaning blade with a solenoid coil.

Japanese Patent Application Laid-Open No. 6-067583 JP 2003-005580 A JP 2003-005597 A

  An object of the present invention is to provide an image forming apparatus in which deposits are stably removed from the surface of an image carrier.

An image forming apparatus according to claim 1 comprises:
An image carrier that forms a toner image on the surface and holds the toner image on the surface;
An image forming unit for forming a toner image on the surface of the image carrier;
A transfer fixing unit for transferring and fixing the toner image formed on the surface of the image carrier onto a recording medium;
A cleaning member having a member main body that contacts the surface of the image carrier to remove deposits from the surface, and a sensor unit that contacts the member main body and outputs a signal corresponding to the distortion of the member main body; A toner supply unit that supplies toner to the surface of the image carrier based on a signal from the sensor unit;
It is provided with.

An image forming apparatus according to claim 2
The toner supply unit supplies toner to the image holding member when a signal from the sensor unit indicates an actual distortion shortage with respect to a distortion necessary for removing the attached matter. And

An image forming apparatus according to claim 3
The sensor unit outputs a plurality of signals corresponding to distortions at a plurality of locations arranged along the surface of the image carrier of the member body,
The toner supply unit is located at a position on the image carrier where a portion corresponding to a signal representing an actual shortage of distortion with respect to the distortion necessary for removing the adhered substance is in contact among the plurality of signals. It is characterized by supplying toner.

An image forming apparatus according to claim 4
The cleaning member includes the member main body, and a sensor unit made of a metal film attached to a place where the member main body avoids a place where the member main body contacts the image holding body.

An image forming apparatus according to claim 5
The cleaning member includes the member main body, and a sensor unit made of a metal film deposited at a place where the member main body avoids a place where the member main body comes into contact with the image holding body.

An image forming apparatus according to claim 6
The image forming unit is characterized in that the toner image is formed on the surface of the image holding member with toner to which fluorine-based particles are externally added.

  According to the image forming apparatus of the first aspect, the deposit is stably removed from the surface of the image carrier.

  According to the image forming apparatus of the second aspect, the removal of the deposit is stabilized by simple control.

  According to the image forming apparatus of the third aspect, the removal of the adhering matter is stabilized at each location on the surface of the image carrier.

  According to the image forming apparatus of the fourth aspect, even if the sensor unit is attached to the member main body, the deformation of the member main body is not hindered.

  According to the image forming apparatus of the fifth aspect, the followability of the sensor unit with respect to the member main body is high as compared with the case where the sensor unit is not a deposited metal film.

  According to the image forming apparatus of the sixth aspect, excessive wear on the surface of the image carrier due to the cleaning member is suppressed.

1 is a schematic configuration diagram of a printer. It is a figure which shows the mode of the front-end | tip of the cleaning blade which contacted the to-be-cleaned body which moves to a predetermined direction. It is a figure which shows a mode when the frictional force of the cleaning blade front-end | tip with respect to the to-be-cleaned body which moves to a predetermined direction is insufficient. It is an external appearance perspective view from the surface side of a cleaning blade. It is a figure which shows the detail of a strain gauge. It is a graph which shows the change of the resistance value of a strain gauge. FIG. 2 is an internal block diagram of a toner band control unit also shown in FIG. 1. It is a detailed block diagram of the Wheatstone bridge circuit shown in FIG. It is a graph which shows the change of the resistance value of the strain gauge arranged by the front and back of the cleaning blade.

  Hereinafter, embodiments of the image forming apparatus of the present invention will be described.

  FIG. 1 is a schematic configuration diagram of a printer.

  The printer 1 shown in FIG. 1 generates a photoconductor roll 10, a charging roll 11 for applying a charge to the surface of the photoconductor roll 10, and laser exposure light based on an image signal transmitted from the outside. A laser exposure device 12 that irradiates the roll 10, a developing device 13 that contains a developer containing toner, a paper cassette 16 that contains recording paper, and a paper transport device that pulls out and transports the recording paper from the paper cassette 16. 17, a transfer roll 14 for transferring the toner image held on the surface of the photosensitive roll 10 onto the recording paper conveyed in the direction of arrow B, and recording by heating and pressurizing the toner image on the recording paper. A fixing unit 15 that fixes a toner image on a sheet, a cleaning device 20 that cleans the surface of the photoreceptor roll 10, and a toner bar that controls the formation of a toner band. And a de-controller 100. The developing device 13 has a developing roll 133 that conveys the developer to an area between the photosensitive roll 10 while rotating. The developer contained in the developing unit 13 includes, in addition to the toner, a magnetic carrier that is a charge-providing particle and a magnetic particle that frictionally charges the toner by friction with the toner, and a photoreceptor roll surface by a cleaning blade Fluorine-based particles that suppress excessive wear are included. Examples of the fluorine-based particles include, but are not limited to, perfluoroalkyl vinyl ether copolymers, polytetrafluoroethylene, and tetrafluoroethylene / hexafluoropropylene copolymers.

The preferred cumulative volume average particle diameter D ₅₀ of the fluorine-based particles is 0.1 to 10 μm.

Here, the cumulative volume average particle diameter D ₅₀ is based on, for example, a particle size distribution measured with a measuring instrument such as Coulter Counter TA-II (manufactured by Beckman-Coulter), Multisizer II (manufactured by Beckman-Coulter). draw a cumulative distribution in volume relative to divided particle size ranges (channels) from the respective small diameter side Te, it defines the particle diameter at a cumulative 50% and cumulative volume-average particle diameter D _50. If an appropriate amount of fluorine-based particles is accumulated in the cleaning blade portion, excessive wear on the surface of the photosensitive roller is suppressed. On the other hand, if a large amount is accumulated, the cleaning ability is remarkably lowered by excessively reducing the friction between the cleaning blade and the photosensitive member.

  The printer 1 is an embodiment of the image forming apparatus of the present invention. The photoreceptor roll 10 corresponds to an example of an image carrier according to the present invention, and the combination of a charging roll 11, a laser exposure device 12, and a developing device 13 corresponds to an example of an image forming unit according to the present invention. To do. Further, the combination of the transfer roll 14 and the fixing device 15 corresponds to an example of the transfer fixing unit referred to in the present invention. A combination of the toner band controller 100, the charging roll 11, the laser exposure device 12, the developing device 13, and the transfer roll 14 corresponds to an example of a toner supply unit according to the present invention. Although the printer 1 is a monochromatic image dedicated machine, the present invention may be applied to a color image machine.

  The flow of the image forming operation in the printer 1 will be briefly described.

  In the printer 1 shown in FIG. 1, an electric charge is applied to the surface of the photoreceptor roll 10 rotating in the direction of arrow A by the charging roll 11, and the image transmitted from the outside to the surface of the photoreceptor roll 10 to which the charge is applied. The laser exposure light based on the signal is irradiated from the laser exposure device 12, whereby an electrostatic latent image is formed on the surface. The developer accommodated in the developing unit 13 is supplied to the surface of the developing roll 133 and is transported to a region between the developing roll 133 and the photoreceptor roll 10, and the photoreceptor roller is transported by the toner in the transported developer. An electrostatic latent image of 10 surfaces is developed. The toner image obtained by this development is transferred by the transfer roll 14 onto the recording paper conveyed in the arrow B direction. Thereafter, the toner image on the recording paper is melted and fixed on the recording paper by a fixing device 15 that heats and pressurizes the toner image. Residue remaining on the portion of the photoreceptor roll 10 where the transfer of the toner image has been completed is downstream of the transfer roll 14 in the direction of arrow A and upstream of the charging roll 11 and on the photoreceptor roll 10. It is removed by scraping the cleaning blade 21 whose tip contacts the entire width along the center of rotation. The removed residue is stored in the residue storage box 23. As will be described in detail later, strain gauges 22 made of a metal film are deposited on the cleaning blade 21 at a plurality of locations along the surface of the photoreceptor roll 10, and the resistance values of the plurality of strain gauges 22 are as follows. It changes in accordance with the strain at each location of the cleaning blade 21 where the strain gauge 22 is deposited. The cleaning blade 21 corresponds to an example of a member main body according to the present invention, and the strain gauge 22 corresponds to an example of a sensor unit according to the present invention. A combination of the cleaning blade 21 and the strain gauge 22 corresponds to an example of the cleaning member according to the present invention.

  By the way, the cleaning with the cleaning blade on the surface of the photoreceptor roll as the object to be cleaned is caused by a phenomenon called “stick-slip phenomenon” between the cleaning blade in contact with the surface of the photoreceptor roll and the surface of the photoreceptor roll. Made.

  This stick-slip phenomenon is a phenomenon in which the “stick state” and the “slip state” are repeated. The “stick state” is a phenomenon in which toner or fluorine on the surface of the photoreceptor roll is cleaned by a cleaning blade whose tip contacts the surface of the rotating photoreceptor roll. Particles, other external additives (medium-sized silica, large-diameter silica, etc.), and deposits such as discharge products are removed. These removed toner, fluorine-based particles, and other external additives (medium-sized silica, large-diameter Silica, etc.), discharge products, etc. are deposited on the contact portion between the surface of the photoreceptor roll and the tip of the cleaning blade, and the force that tries to engulf the tip of the cleaning blade gradually increases. It means a condition that gradually increases. The “slip state” means deposits such as toner, fluorine-based particles, other external additives (medium diameter silica, large diameter silica, etc.), discharge products, etc. at the contact portion between the surface of the photoreceptor roll and the cleaning blade tip. When the amount exceeds a certain level, the deposit is broken by the cleaning blade, and the force for entraining the tip of the cleaning blade is suddenly reduced. At the contact portion between the surface of the photoreceptor roll and the tip of the cleaning blade, cleaning that occurs due to repeated deposition (“stick state”) and collapse (“slip state”) of the deposit removed by the cleaning blade from the surface of the photoreceptor roll Cleaning is performed by the behavior of the blade tip.

  FIG. 2 is an enlarged view of the tip of the cleaning blade in contact with the surface of the photoreceptor roll.

  In FIG. 2, the fluorinated particles 200 and the toner 300 are deposited in the deposit in which deposits removed from the photoreceptor roll are deposited due to the tip of the cleaning blade being in contact with the photoreceptor roll rotating in the direction of the arrow. It shows a mix. As shown in FIG. 2, deposits mixed with toner and fluorine-based particles are deposited on the contact portion between the surface of the rotating photoreceptor roll and the tip of the cleaning blade, causing a stick state and distorting the cleaning blade. The stress that distorts the cleaning blade in this way becomes a force for removing the deposits on the photoreceptor roll, so that the fluorine particles 200 and the toner 300 are further deposited on the tip of the cleaning blade, and the slip state is eventually reached. That is, the stick-slip phenomenon occurs when the fluorine-based particles 200 and the toner 300 are mixed on the photoreceptor roll.

  However, when the proportion of toner in the deposit on the surface of the photoreceptor roll decreases, the proportion of toner in the deposit at the tip of the cleaning blade also decreases, and the proportion of fluorine-based particles increases accordingly. It has been found by the inventor's research that it is difficult to generate.

  FIG. 3 is a diagram illustrating a state in which deposits at the contact portion between the surface of the rotating photoconductor roll and the tip of the cleaning blade are occupied by fluorine-based particles.

  FIG. 3 shows that the amount of toner in the deposit at the contact portion between the rotating surface of the photosensitive roll and the tip of the cleaning blade decreases and is occupied by fluorine-based particles. It is shown that it is less than shown. This is because when the proportion of toner in the deposit is low, the viscosity of the deposit is low, and the proportion of the fluorine-based particles is high, and the photoreceptor roll, which is the source of the action of entraining the tip of the cleaning blade This is presumably because the frictional force between the surface and the tip of the cleaning blade is significantly reduced.

  If the state in which the toner occupies a low ratio as shown in FIG. 3 is left as it is, it becomes difficult to secure a frictional force between the surface of the photoreceptor roll and the tip of the cleaning blade, and a stick-slip phenomenon occurs. Insufficient cleaning. As a result, the removal of deposits on the surface of the photoreceptor roll is insufficient. In other words, if the cleaning blade is sufficiently distorted, it can be said that a sufficient frictional force is ensured between the surface of the photoreceptor roll and the tip of the cleaning blade, and a sufficient cleaning property can be obtained by the stick-slip phenomenon.

  Therefore, in the printer 1 of this embodiment, a strain gauge 22 whose resistance value changes according to strain is attached to the cleaning blade 21, and the mechanism will be described later, but a signal indicating the magnitude of the resistance value of the attached strain gauge 22 Is detected in real time, and the magnitude of the frictional force against the surface of the photoreceptor roll at the tip of the blade is estimated.

  In the printer 1, the strain gauge 22 is moved along the rotational center of the photosensitive roll 10 of the cleaning blade 21 whose tip contacts the surface of the photosensitive roll 10 along the rotational center of the photosensitive roll 10. In addition, the magnitude of the frictional force at the blade tip in the vicinity of each of these five locations is estimated. For example, in the case where A4 size printing using only the vicinity of the center of the photoreceptor roll 10 capable of printing at maximum A3 size is continuous, a large amount of toner is distributed in the deposit on the center portion of the photoreceptor roll 10. On the other hand, since the toner image is not formed at both end portions except for the central portion of the photoreceptor roll 10, it is considered that the ratio of the tetrafluorinated resin particles is high. For this reason, the cleaning performance is considered to be different at each position along the tip of the cleaning blade 21. In this embodiment, the above-described five strain gauges 22 are used to confirm the cleaning performance at each position. ing.

  FIG. 4 is an external perspective view of the cleaning blade in the present embodiment.

  FIG. 4 shows a state in which the strain gauges 22 shown in FIG. 1 are arranged at five locations along the surface of the photoreceptor roll 10 on the surface 211 of the cleaning blade 21.

  In the printer 1, signals representing the magnitudes of resistance values of the strain gauges 22 attached to the five locations on the surface 211 of the cleaning blade 21 are detected, and the signals on the cleaning blades to which the strain gauges 22 are attached are detected. The magnitude of the frictional force at the nearby blade tip is estimated.

  Here, the details of the strain gauge 22 attached to the cleaning blade 21 and the relationship between the strain of the cleaning blade 21 and the resistance value of the strain gauge 22 will be described first.

  FIG. 5 is a diagram showing details of the strain gauge.

  The strain gauge 22 shown in FIG. 5 is a metal film composed of a gauge pattern portion 221 consisting of a narrow pattern connected in a zigzag shape and gauge tab portions 222 connected to both ends of the gauge pattern portion 221 respectively. The gauge pattern portion 221 and the gauge tab portion 222 are deposited on the cleaning blade 21. For this reason, the strain gauge 22 is difficult to peel off from the surface 211 of the cleaning blade 21 and has high followability to the surface 211 of the cleaning blade 21.

  When the photosensitive roll 10 rotates in the direction of arrow A shown in FIG. 4, the cleaning blade 21 is curved so that the tip 210 side protrudes toward the front side in FIG. 5 (see FIG. 2). Shrink in the L direction. As a result, the cross-sectional area of the gauge pattern portion 221 is increased and the distance is slightly reduced, so that the resistance value of the strain gauge 22 is reduced.

  Further, the strain gauge 22 shown in FIG. 5 is deposited at a distance from the tip 210 of the cleaning blade 21 so as not to hinder the distortion of the tip 210 that greatly affects the strain of the entire cleaning blade.

  The gauge tab portion 222 has a pattern wider than the gauge pattern portion 221 so that the connection of the gauge lead 223 does not affect the expansion and contraction of the gauge pattern portion 221.

  The gauge length L of the gauge pattern portion 221 is preferably in the range of 0.2 mm to 5 mm. Moreover, it is preferable that the gauge width W of the gauge pattern part 221 exists in the range of 0.5 mm-5 mm. If it is smaller than this range, processing with high accuracy is required, and noise to the signal increases. On the other hand, if the ratio is larger than this range, the ratio of the cleaning blade 21 to the surface 212 increases, so that the followability of the resistance value against the distortion of the cleaning blade 21 decreases. Note that the gauge tab portion 222 is connected to the toner band controller 100 by a gauge lead 223. The material of the metal film is selected from the group consisting of aluminum, zinc, nickel, titanium, vanadium, chromium, tantalum, iron, manganese, silicon, and alloys, oxides, nitrides, and silicides thereof. Is mentioned.

  FIG. 6 is a graph showing a change in the resistance value of the strain gauge.

  FIG. 6 shows a change in resistance value of the strain gauge 22 deposited at one place on the surface 211 of the cleaning blade 21.

  A solid line in FIG. 6 indicates a change in resistance value of the strain gauge 22 in an appropriate state in which a strong stress is generated between the blade tip 210 near the portion where the strain gauge 22 is deposited and the photoreceptor roll 10. The dotted line in FIG. 6 shows a change in the resistance value of the strain gauge 22 in an improper state where the stress between the blade tip 210 near the portion where the strain gauge 22 is deposited and the photoreceptor roll 10 is weak. .

  In FIG. 6, in the above-described proper state, the resistance value Rv of the strain gauge 22 was Rv0 while the photoconductor roll 10 was stopped, but greatly decreased to Rv1 while the photoconductor roll 10 was rotating. The situation is shown. On the other hand, when the photosensitive roll 10 is stopped, the resistance value Rv of the strain gauge 22 is Rv0 in the same manner as the proper state when the photosensitive roll 10 is stopped. Since the frictional force between the tip 210 of the cleaning blade 21 and the photosensitive roll 10 is small and the distortion of the cleaning blade 21 is also small, it is reduced only to Rv2 larger than Rv1 in the proper state. As described above, the resistance value of the strain gauge 22 reflects the frictional force of the blade tip 210 near the portion where the strain gauge 22 is deposited on the photosensitive roll 10.

  Next, a method for detecting a signal indicating the magnitude of the resistance value of the strain gauge 22 will be described.

  FIG. 7 is an internal block diagram of the toner band controller shown in FIG.

  The toner band control unit 100 illustrated in FIG. 7 includes a Wheatstone bridge circuit 101, a detection unit 102, a determination unit 103, and a toner band formation instruction unit 104. Although not shown in FIG. 7, the Wheatstone bridge circuit 101 and the detection unit 102 are provided in the same number as the strain gauges 22, that is, five each.

  FIG. 7 also shows the photoreceptor roll 10 shown in FIG. 1, a cleaning blade 21 with a strain gauge 22, a charging roll 11, a laser exposure device 12, a developing device 13, and a transfer roll 14. The five Wheatstone bridge circuits 101 and the five strain gauges 22 are connected via gauge leads 223, respectively.

  FIG. 8 is a detailed block diagram of the Wheatstone bridge circuit shown in FIG.

  A Wheatstone bridge circuit 101 shown in FIG. 8 includes a first resistance element 1011 having a resistance value R1, a second resistance element 1012 having a resistance value R2, a third resistance element 1013 having a resistance value R3, and a DC power supply 1010. In the circuit 101, a strain gauge 22 whose resistance value Rv changes is used as a fourth resistance element.

  A DC power supply 1011 is connected to the first connection point A between the strain gauge 22 and the third resistance element 1013 and the second connection point B between the first resistance element 1011 and the second resistance element 1012. . Further, the third connection point C between the first resistance element 1011 and the strain gauge 22 and the fourth connection point D between the second resistance element 1012 and the third resistance element 1013 are also shown in FIG. The detection unit 102 is connected. The detection unit 102 includes a resistor inside.

  Here, when the following formula (1) holds, the potential difference between the third connection point C and the fourth connection point D becomes zero, and the current detected by the detection unit 102 becomes zero.

Rv / R1 = R3 / R2 (1)
In the Wheatstone bridge circuit 101, the above formula (1) is established according to the resistance value Rv0 of the strain gauge 22 when the cleaning blade 21 is almost free of distortion as shown in FIG. Other resistance values R1, R2, and R3 are set so that Rv0 / R1 = R3 / R2 holds. Therefore, when the cleaning blade 21 changes from a state having almost no strain as shown in FIG. 3 to a state distorted as shown in FIG. 2, the resistance value Rv of the strain gauge 22 is Rv1 smaller than Rv0 described above. Become. Then, since the potential at the fourth connection point D becomes higher than the potential at the third connection point C, the detection unit 102 between the fourth connection point D and the third connection point C has a fourth connection point. A current flows from D toward the third connection point C. Therefore, the current flowing through the detection unit 102 increases as the resistance value Rv of the strain gauge 22 decreases, that is, as the strain of the cleaning blade 21 increases. Therefore, the current value detected by the detection unit 102 decreases as the appropriate state changes from the appropriate state.

  The five detection units 102 transmit a signal corresponding to the detected current value, that is, a signal having a higher level as the detected current value is larger, to the determination unit 103 shown in FIG. 7 in real time.

  The determination unit 103 monitors whether or not the levels of the signals transmitted from the five detection units 102 are lower than a preset reference level, and when a signal having a level lower than the reference level is transmitted. The position on the cleaning blade to which the strain gauge 22 connected to the detection unit 102 that transmitted the signal is attached is assumed to be in the above-mentioned inappropriate state and the position information below the reference level. Both the received signal level and the difference information indicating the difference with respect to the reference level are transmitted to the toner band formation instructing unit 104.

  In the toner band formation instructing unit 104, the charging roll 11, laser exposure is performed so that the higher the difference represented by the received difference information is, the higher the toner band is formed at the position on the photoreceptor roll corresponding to the received position information. The device 12 and the developing device 13 are controlled. The toner band formed in this way is not transferred onto the recording paper by the transfer roll 14 but goes to the blade tip 210 in an inappropriate state and supplies toner to the blade tip 210. Such toner supply returns the blade tip 210 in an inappropriate state to an appropriate state. As a result, the frictional force of the blade tip 210 with respect to the photoreceptor roll 10 is recovered and appropriately distorted, so that the resistance value of the strain gauge 22 attached in the vicinity of the blade tip 210 is sufficiently lowered. become. As a result, since the current detected by the detection unit 102 increases, the signal level transmitted from the strain gauge 22 to the determination unit 103 exceeds the preset reference level. Transmission of position information and the like to the toner band formation instructing unit 104 is stopped.

  The embodiment described above is an example in which the strain gauge 22 is vapor-deposited only on the front surface 211 and the rear surface 211 of the cleaning blade 21, but in the present invention, the surface of the cleaning blade 21 is described as described below. Sensors may be deposited on both the 211 and the back surface.

  FIG. 9 is a graph showing changes in resistance values of strain gauges arranged one by one on the front and back surfaces of the cleaning blade.

  The graph shown in the upper part of the graph shown in FIG. 9 represents the same graph as the graph shown in FIG. 6, that is, the change in the resistance value of the strain gauge 22 arranged on the surface 211 of the cleaning blade 21. On the other hand, the lower part shows the change in the resistance value of the strain gauge 22 arranged on the back surface of the same cleaning blade 21.

  In FIG. 9, the resistance value of the strain gauge 22 disposed on the surface 211 of the cleaning blade 21 is lower when the tip 210 of the cleaning blade 21 is distorted than when it is not distorted ( 9), the resistance value of the strain gauge 22 disposed on the back surface of the cleaning blade 21 is distorted on the front surface 210 and the back surface of the cleaning blade 21, so that the tip 210 of the cleaning blade 21 is distorted. It is shown that the direction of rising is higher than that of not distorting (data in the lower part of FIG. 9).

  In this way, the resistance value of the strain gauge 22 reflects the distortion of the blade tip at the position where the cleaning gauge 21 is placed, whether it is the front surface 211 or the back surface of the cleaning blade 21. Only the back surface of the cleaning blade 21 may be provided, and further, it may be disposed on both the front and back surfaces.

  In the above description, the metal film as the strain gauge is deposited on the cleaning blade. However, in the present invention, the metal film as the strain gauge may be attached to the cleaning blade with an adhesive. Hereinafter, a case where a metal film is attached with an adhesive will be described.

  In this case, the length (gauge length) L and width (gauge width) W and the material of the metal thin film are the same as those of the strain gauge 22 shown in FIG. The film thickness is not particularly limited, but a film having a thickness of several μm is preferably used in order to increase productivity. In order to detect the distortion of the cleaning blade with high accuracy, it is preferable to use a cleaning blade having a thickness of 0.1 μm to 2.0 μm. Further, the adhesive includes a thermosetting type and a liquid type. As the thermosetting adhesive, epoxy resin, phenol resin, polyurethane resin, silicon resin, polyimide resin, or the like is used. As the liquid adhesive, a cyanoacrylate adhesive, an epoxy, a phenol epoxy, or the like is used.

  When the metal film is bonded with an adhesive as described above, the response is inferior to the amount of the adhesive as compared with the case where the metal film is deposited. Therefore, it is necessary to use the adhesive as thin as possible.

  In the above description, the printer has been described as an example of the image forming apparatus according to the present invention. However, the image forming apparatus according to the present invention can be a facsimile machine or the like as well as a copying machine as long as it is an electrophotographic image forming apparatus. But you can.

  Further, as the image forming apparatus according to the present invention, a direct transfer type printer that directly transfers a developed image on a photoconductive roll onto a conveyed recording sheet using a transfer roll has been described as an example. The image forming apparatus may be an indirect transfer type image forming apparatus that transfers a developed image onto a recording sheet via a transfer belt.

  In addition, the image carrier referred to in the present invention has been described by taking a photoreceptor roll adopting a roll method as an example, but the image carrier referred to in the present invention may be a photoreceptor belt employing a circulation belt method. Good.

  Furthermore, the image forming unit referred to in the present invention has been described with an example including a charging roll, an exposure device, and a developing device. However, the image forming unit referred to in the present invention is not charged or developed on the image carrier. An image may be directly formed.

  In addition, the transfer fixing unit according to the present invention has been described as an example in which the image is transferred by a transfer roll and then fixed by a fixing device. However, the transfer fixing unit according to the present invention may perform transfer and fixing at the same time. .

(Example)
Examples of the present invention will be described below, but the present invention is not limited to these examples.

  A commercially available printer is remodeled into a printer having the same configuration as that of the embodiment described with reference to FIGS. 1 to 8 and the function of the toner band controller 100 can be switched between start and stop. 3 and comparative examples were tested. In Examples 1, 2, 3 and Comparative Examples, A4 paper (P paper, manufactured by Fuji Xerox Office Supply Co., Ltd.) was used to print 30 thousand halftone image charts, and then A3 paper was used. One half-tone image was printed, and the density difference (ΔSAD) between the passing portion and the non-passing portion of the previous A4 paper in the halftone image of this A3 paper was detected and evaluated. is there.

  In Example 1, the photoconductor wear control agent contained in the developer together with the toner is polytetrafluoroethylene which is a kind of tetrafluorinated resin particles (hereinafter, this polytetrafluoroethylene is referred to as PTFE. Daikin Industries, Ltd. “Lublon L2” Average particle size Primary particle size: 0.3 (μm) by electron microscope, secondary particle size: 5 (μm) by light transmission method), and the function of the toner band control unit 100 is activated. This is the case.

  In Example 2, the amount of toner in the developer and the photosensitive member were changed except that the photoconductor wear control agent was a perfluoroalkyl vinyl ether copolymer (hereinafter, this perfluoroalkyl vinyl ether copolymer is referred to as PFA). The same as Example 1 including the amount of wear control agent.

  In Example 3, the photoconductor wear control agent was changed to tetrafluoroethylene / hexafluoropropylene copolymer (hereinafter, this tetrafluoroethylene / hexafluoropropylene copolymer is referred to as FEP). The same as Example 1 including the amount of toner in the developer and the amount of photoreceptor wear control agent.

  The comparative example is the same as the first embodiment, including the toner amount in the developer and the photoreceptor wear control agent amount, except that the function of the toner band control unit 100 is stopped.

  For evaluation, ΔSAD of less than 0.02 is “◎”, 0.02 to less than 0.03 is “◯”, 0.03 to less than 0.04 is “Δ”, 0.04 or more is “×”. 'And.

  As shown in Table 1, the experimental results show that the evaluation of the density difference (ΔSAD) in Example 1 is “Δ”, the evaluation of the density difference in Example 2 is “◯”, and the evaluation of the density difference in Example 3 is “◎”, the evaluation of the density difference in the comparative example was “×”. From Example 1 and the comparative example, it was confirmed that the function of the toner band control unit 100 is effective in removing the deposits from the surface of the photoreceptor roll 10 by the cleaning blade 21. Further, from Example 1 to Example 3, when the toner amount in the developer and the photoreceptor wear control agent amount are the same, the function of the toner band control unit 100 is that the photoreceptor wear control agent is FEP. It was confirmed that this is particularly effective. This is presumably because the friction coefficient of FEP is larger than that of PTFE and PFA.

DESCRIPTION OF SYMBOLS 1 Printer 10 Photoconductor roll 100 Toner band control part 101 Wheatstone bridge circuit 102 Detection part 103 Judgment part 104 Toner band formation instruction part 11 Charging roll 12 Laser exposure device 13 Developing device 14 Transfer roll 15 Fixing device 16 Paper cassette 17 Paper conveyance device 20 Cleaning Device 21 Cleaning Blade 210 Tip 211 Surface 22 Strain Gauge 221 Gauge Pattern Part 222 Gauge Tab Part 223 Gauge Lead 23 Residue Storage Box 200 Fluorine Particle 300 Toner

Claims (6)

An image carrier on which a toner image is formed and which holds the toner image on the surface;
An image forming unit for forming a toner image on the surface of the image carrier;
A transfer fixing unit for transferring and fixing a toner image formed on the surface of the image carrier onto a recording medium;
A cleaning member having a member main body that contacts the surface of the image carrier to remove deposits from the surface, and a sensor unit that contacts the member main body and outputs a signal corresponding to distortion of the member main body; A toner supply unit that supplies toner to the surface of the image carrier based on a signal from the sensor unit;
An image forming apparatus comprising:   The toner supply unit supplies toner to the image carrier when a signal from the sensor unit indicates an actual distortion shortage with respect to a distortion necessary for removing the attached matter. The image forming apparatus according to claim 1. The sensor unit outputs a plurality of signals corresponding to distortions at a plurality of locations arranged along the surface of the image carrier of the member main body,
The toner supply unit is located at a position on the image carrier where a portion corresponding to a signal representing an actual shortage of distortion with respect to the distortion necessary for removing the deposit is in contact among the plurality of signals. 3. The image forming apparatus according to claim 1, wherein the image forming apparatus supplies toner.   The said cleaning member has the said member main body and the sensor part which consists of a metal film attached to the location which avoided the location where this member main body contacts the said image holding body. 4. The image forming apparatus according to claim 1.   2. The cleaning member according to claim 1, wherein the cleaning member includes the member main body, and a sensor unit made of a metal film deposited at a place where the member main body avoids a place where the member main body contacts the image holding body. 5. The image forming apparatus according to claim 1.   6. The image forming unit according to claim 1, wherein the image forming unit forms the toner image on the surface of the image holding member with a toner to which fluorine-based particles are externally added. Image forming apparatus.

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