JP4973017B2 - Image forming apparatus - Google Patents

Description

  The present invention relates to an image forming apparatus that forms an image composed of a fixed image on a recording medium by fixing a developed image on the recording medium.

2. Description of the Related Art Conventionally, image forming apparatuses such as printers and copiers have been widely used, and technologies relating to various elements constituting such image forming apparatuses have also been widely used. Among image forming apparatuses that employ an electrophotographic method, a pattern to be printed by forming an electrostatic latent image having a potential different from the surrounding potential on a photosensitive member such as a photosensitive drum. The electrostatic latent image formed in this way is developed with a developer containing toner, transferred onto a recording medium, and then fixed. On the other hand, residual toner that remains without being transferred may adhere to the surface of the photoconductor after the transfer. In an electrophotographic image forming apparatus, such residual toner remains in preparation for the next image forming process. A cleaning means for removing toner is often provided. As a cleaning method, a cleaning edge called a cleaning blade is pressed against the photoconductor to scrape the residual toner (for example, see Patent Document 1), or the brush is rotated to remove the residual toner from the photoconductor. There is known a fur brush cleaning method (see, for example, Patent Document 2). In particular, the blade cleaning method using a cleaning blade removes residual toner with a simple mechanism. Therefore, the provision of the cleaning unit reduces the cost and the size of the cleaning unit, which is desirable.
JP 2003-241607 A JP 2003-186364 A

  In the blade cleaning method, since the cleaning blade is always in pressure contact with the photoconductor, the friction between the cleaning blade and the photoconductor is large. This friction is alleviated to some extent by the residual toner functioning as a lubricant. However, when the image is formed with a small amount of residual toner, such as when forming an image with a low amount of toner applied to the image for a long time, this friction causes this friction. The temperature of the cleaning blade rises. The cleaning blade is often made of rubber, and rebound resilience is reduced at high temperatures and is easily deformed. In the cleaning blade that is easily deformed, the portion that is in pressure contact with the photoconductor is repeatedly deformed and recovered, so that a so-called stick slip occurs. Blade squeal) occurs.

  In view of the above circumstances, an object of the present invention is to provide an image forming apparatus that reduces blade noise.

In order to achieve the above object, an image forming apparatus of the present invention comprises:
A developed image is formed on the image carrier, the developed image is transferred from the image carrier to a recording medium, and the developed image on the recording medium is fixed, whereby an image composed of a fixed image is formed on the recording medium. In the image forming apparatus to be formed,
A cleaning blade in contact with the image carrier;
A vibration detection unit that directly or indirectly detects the vibration of the cleaning blade;
And a cooling unit that cools the cleaning blade when the vibration detecting unit detects vibration.

  The image forming apparatus of the present invention cools the cleaning blade to lower its temperature when the cleaning blade vibrates due to stick slip as the temperature rises. As a result, the cleaning blade is hardly deformed, sticking slip of the cleaning blade is suppressed, and blade noise is reduced.

  In the image forming apparatus of the present invention, “the cleaning blade has a resilience elastic modulus at 25 ° C. in the range of 20% to 80% and a Young's modulus at 25 ° C. in the range of 70 MPa to 90 MPa. It is possible to adopt a form in which the body is used as a material, and the vibration detection unit detects vibrations having a frequency belonging to the region of 150 Hz to 300 Hz.

  The cleaning blade is required to have an appropriate elasticity when pressed against the image carrier and scrapes off the residual toner. As a material satisfying such a condition, the resilience elastic modulus at 25 ° C. is 20% to 80%. An elastic body belonging to the range and having a Young's modulus at 25 ° C. in the range of 70 MPa to 90 MPa is often used. Since the frequency at which the cleaning blade made of such an elastic body vibrates due to stick-slip becomes a frequency in the region of 150 Hz to 300 Hz, the image forming apparatus employing this type of cleaning blade has a frequency in this region. Generation of stick-slip is detected by detecting vibration.

  Further, in the image forming apparatus of the present invention, “the cooling section has a Peltier element that is in contact with the cleaning blade, and the cleaning blade is cooled by the Peltier element” is a preferable form. .

  The Peltier element can absorb the heat of the cleaning blade only by passing an electric current, and it is easy to cool the cleaning blade.

  Further, in the image forming apparatus of the present invention, a form of “having a heat conduction member that contacts the cleaning blade and equalizes the temperature distribution of the cleaning blade” is a preferable form.

  Of the entire cleaning blade, the portion closer to the image carrier is more likely to become hot due to the effect of friction, but due to the presence of the heat conduction member, the heat generated in the cleaning blade diffuses and the temperature rises rapidly. Alleviated.

  In the image forming apparatus of the present invention, “the temperature detection unit that directly or indirectly detects the temperature of the cleaning blade is provided, and the cooling unit is configured to detect the temperature even when the cleaning blade is cooled. When the detection result of the part shows a predetermined low temperature state, the cooling blade is stopped cooling "is a preferable mode.

  Here, the “predetermined low temperature state” means that the cleaning blade is in a state where the temperature is equal to or lower than the predetermined threshold temperature, or a state where the temperature is equal to or lower than the predetermined threshold temperature for a predetermined time or longer. This means that the temperature of is low.

  If the temperature of the cleaning blade is too low, moisture in the air condenses on the cleaning blade and the moisture reaches the image holding member, which may cause problems such as transfer defects. When it is detected that the cleaning blade is in a predetermined low temperature state, excessive cooling is avoided by stopping cooling of the cleaning blade by the cooling unit.

  According to the present invention, blade squeal is reduced.

  Hereinafter, embodiments of the present invention will be described.

  FIG. 1 is an overall configuration diagram of an image forming apparatus according to the present exemplary embodiment.

  The image forming apparatus of this embodiment is a color printer for single-sided output.

  The image forming apparatus 1000 includes electrophotographic laminated photoreceptors 61Y, 61M, 61C, and 61K, chargers 65Y, 65M, 65C, and 65K that charge the photoreceptors, and the charged photoreceptors. The exposure unit 7 that forms an electrostatic latent image for each color of black (K), cyan (C), magenta (M), and yellow (Y) by laser light irradiation, and the electrostatic latent image on each photosensitive member for each color Developing units 64K, 64C, 64M, and 64Y are provided that develop toner images of the respective colors by developing with a developer containing the toner. Here, the toner images of the respective colors correspond to an example of the developed image referred to in the present invention. The image forming apparatus 1000 also includes an intermediate transfer belt 5 that receives the transfer of each color toner image formed on each photoconductor and conveys the toner image, and the primary of each color toner image to the intermediate transfer belt 5. The primary transfer rolls 50K, 50C, 50M, and 50Y to which the transfer is performed, the secondary transfer roll pair 9 that performs the secondary transfer to the paper, the fixing device 10 that fixes the toner image, and the four developing devices, respectively. Four toner cartridges 4K, 4C, 4M and 4Y for replenishing component toners, and a tray 1 for storing paper are also provided. Here, the intermediate transfer belt 5 circulates and moves in the direction of arrow A in the figure while being stretched between the secondary transfer roll 9b and the drive roll 5a while receiving the drive force from the drive roll 5a.

  Next, an image forming operation in the image forming apparatus 1000 will be described.

  The four photoconductors 61Y, 61M, 61C, and 61K are charged by the chargers 65Y, 65M, 65C, and 65K, respectively, and further, an electrostatic latent image is formed on each photoconductor by receiving laser light emitted from the exposure unit 7. It is formed. The formed electrostatic latent image is developed with toners of respective colors by the developing devices 64K, 64C, 64M, and 64Y to form a toner image. The toner images of the respective colors formed in this way are yellow (Y), magenta (M), cyan (C) on the intermediate transfer belt 5 in the primary transfer rolls 50K, 50C, 50M, and 50Y corresponding to the respective colors. ) And black (K) are sequentially transferred and superposed to form a multicolor toner image. The multicolor toner image is conveyed to the secondary transfer roll pair 9 by the intermediate transfer belt 5. On the other hand, in response to the formation of such a multicolor toner image, the sheet is taken out from the tray 1 and conveyed by the conveying roll 3, and the position is adjusted by the registration roll pair 8. Then, the multi-color toner image is transferred onto the conveyed paper by the secondary transfer roll pair 9, and the multi-color toner image is fixed on the paper by the fixing device 10. After the fixing process, the sheet having the multicolor toner image passes through the delivery roll pair 13 and is discharged to the discharge tray 2.

  The above is the description of the image forming operation in the image forming apparatus 1000. After the above-described image formation is performed, toner remaining without being primarily transferred exists on the photoreceptors 61Y, 61M, 61C, and 61K. In order to remove the residual toner, each photoconductor is provided with a cleaning blade that is in pressure contact with the photoconductor. Hereinafter, the removal of the residual toner will be described by taking the photoreceptor 61C on which a cyan toner image is formed as an example.

  FIG. 2 is a diagram showing the state of the periphery of the photoreceptor on which the cyan toner image shown in FIG. 1 is formed.

The photoreceptor 61C on which the cyan toner image is formed rotates in the direction B in the drawing while holding the cyan toner image, and the cyan toner image is intermediate from the photoreceptor 61C at the position of the primary transfer roll 50C. Primary transfer is performed on the transfer belt 5. At this time, the photoreceptor 61C
In this case, cyan residual toner 107C is present, and this residual toner 107C is scraped off from the photoreceptor 61C by a cleaning blade 100C provided downstream from the position of the primary transfer roll 50C. This cleaning blade 100C is made of urethane rubber having a rebound resilience at 25 ° C. (based on JIS K6400-3: 2004) of 50% and a Young's modulus at 25 ° C. of 80 MPa.

  The cleaning blade used in the image forming apparatus of the present invention is not limited to the urethane rubber of the above material, but the rebound resilience at 25 ° C. belongs to the range of 20% to 80%, and the Young's modulus at 25 ° C. A cleaning blade made of an elastic body belonging to a range of 70 MPa to 90 MPa is preferable in terms of appropriately scraping off residual toner.

  Below the position where the residual toner 107C is scraped off, there is provided a roll-shaped member having a plurality of openings on the peripheral surface, and a residual toner transport section that rotates about its roll axis. The residual toner 107C that has been rubbed down falls onto the residual toner conveyance portion 105C and is conveyed to a predetermined residual toner storage position while entering the opening. Further, in order to prevent the residual toner 107C from being scattered around when the residual toner 107C is scraped from the photoreceptor 61C, the periphery of the cleaning blade 100C from which the residual toner 107C is scraped is surrounded by a casing 106C.

  Generally, since the cleaning blade is always in pressure contact with the photoconductor, the friction between the cleaning blade and the photoconductor is large. This friction is alleviated to some extent by the residual toner functioning as a lubricant. However, when forming an image with a low density for a long time, such as when an image with low residual toner is formed, this friction causes the temperature of the cleaning blade. As a result, the rebound resilience of the cleaning blade is lowered, and the cleaning blade is easily deformed. In particular, in a tandem type color image forming apparatus such as the image forming apparatus 1000 of the present embodiment shown in FIG. 1, cyan, magenta, and yellow are also output when outputting a monochrome image (an image formed of a black toner image). The photoreceptor on which the toner images of the respective colors are formed rotates with the movement of the intermediate transfer belt at the time of monochrome image formation, so that the residual toner functioning as a lubricant is insufficient, and the cleaning blade is easily deformed by heat. In the cleaning blade that is easily deformed, the portion that is in pressure contact with the photosensitive member is repeatedly deformed and recovered to cause a so-called stick-slip. Blade squeal) occurs.

  The image forming apparatus 1000 shown in FIG. 1 is provided with a device for reducing such blade noise. Below, this device is demonstrated.

  The cleaning blade 100C is supported by a surface facing the residual toner conveying portion 105C attached to the support member 104C, and the vibration of the cleaning blade 100C is vibrated below the support member 104C via the vibration of the support member 104C. 101C of vibration detection parts which detect this are provided. Further, on the surface of the cleaning blade 100C facing the photoreceptor 61C side, a temperature detection unit 103C that detects the temperature of the cleaning blade 100C and a direction perpendicular to FIG. The heat conducting member 102C is provided.

  FIG. 3 is a diagram illustrating the vibration detection unit, the temperature detection unit, and the heat conduction member illustrated in FIG. 2 in a plane along the width of the cleaning blade illustrated in FIG.

  The vibration detection unit 101 </ b> C detects the vibration through the detection of acceleration and generates a signal indicating the magnitude of the vibration, and a vibration signal having a frequency belonging to the region of 150 Hz to 300 Hz among the vibrations detected by the acceleration sensor. A vibration signal having a frequency belonging to this region is sent to the CPU 4 that controls the entire image forming apparatus.

  In general, elasticity such as urethane rubber employed in the cleaning blade 100C of FIG. 2 has a rebound resilience within a range of 20% to 80% and a Young's modulus at 25 ° C. within a range of 70 MPa to 90 MPa. In the body, the frequency when vibrating by stick-slip is a frequency in the region of 150 Hz to 300 Hz.

  Therefore, when a vibration signal having a frequency in this region is transmitted to the CPU 4 by the acceleration sensor and the bandpass filter of the vibration detection unit 101C, the CPU 4 determines that a stick slip has occurred. Here, the combination of the vibration detection unit 101C and the CPU 4 corresponds to an example of the vibration detection unit referred to in the present invention.

  Further, in the image forming apparatus 1000, when the toner image is primarily transferred from the photoreceptor 61C to the intermediate transfer belt 5, an AC voltage of about 600 Hz is included between the primary transfer roll 50C and the photoreceptor 61C. Bias voltage is applied. Although the photoconductor 61C may vibrate slightly due to the influence of the AC voltage, the above-described bias voltage has an influence on the determination of occurrence of stick-slip since the above-described filter cuts off the vibration at a frequency near 600 Hz. do not do.

  The temperature detection unit 103C includes a thermistor that is a semiconductor element whose resistance value changes according to temperature, a power source that supplies current to the thermistor, and an ammeter that measures the value of current flowing through the thermistor. The measurement result by the ammeter is transmitted to the CPU 4, and the CPU 4 detects the temperature of the cleaning blade 100C from the measurement result. Here, the combination of the temperature detection unit 103C and the CPU 4 corresponds to an example of the temperature detection unit according to the present invention.

  The heat conducting member 102C is obtained by enclosing a liquid in a copper member having a hollow inside. Copper has a high thermal conductivity, and the heat conduction member 102C made of such a material is attached to the cleaning blade 100C, whereby the heat of the cleaning blade 100C caused by friction is easily transferred from the cleaning blade 100C to the heat conduction member 102C. In general, the portion closer to the photosensitive member in the entire cleaning blade tends to become hot due to the influence of friction. However, due to the presence of the heat conducting member 102C, the heat generated in the cleaning blade 100C diffuses and becomes abrupt. Temperature rise is alleviated. For example, water can be used as the liquid sealed inside the copper member in the heat conducting member 102C. Here, the heat conducting member 102C corresponds to an example of the heat conducting member according to the present invention.

  In FIG. 3, a cooling unit 108 </ b> C that absorbs heat transmitted to the heat conducting member 102 </ b> C is provided at the right end of the heat conducting member 102 </ b> C. The cooling unit 108C is a planar element, and includes a Peltier element that absorbs heat from one surface and dissipates heat from the other surface when a current flows, and a power source that supplies current to the Peltier element. The heat absorption side surface of the Peltier element is in contact with the heat conduction member 102C. When a current flows through the Peltier element, heat transmitted from the cleaning blade 100C to the heat conduction member 102C is absorbed, and the absorption of such heat causes The cleaning blade 100C is cooled. On the other hand, the heat radiation side surface of the Peltier element faces the right side of the figure, and the periphery of the photoreceptor 61C in FIG. 2 such as the cleaning blade 100C on the left side of the figure from the Peltier element is heated by heat radiated from the Peltier element. It is devised not to. In addition, a vent hole (not shown in FIG. 3) is provided at a position slightly apart in the right direction of the cooling unit 108C, and heat radiated from the Peltier element is transmitted from the vent hole to the outside of the image forming apparatus 1000 in FIG. To be released. The cooling unit 108C is connected to the CPU 4. When the CPU 4 detects that the cleaning blade 100C starts to vibrate at a frequency belonging to the range of 150 Hz to 300 Hz, the CPU 4 causes a current to flow to the Peltier element through the power source of the cooling unit 108C. An instruction is issued and the cleaning blade 100C is cooled. As described above, the cleaning blade 100C is cooled through detection of the vibration of the cleaning blade 100C, so that stick-slip of the cleaning blade is reduced. Here, the combination of the heat conducting member 102C, the cooling unit 108C, and the CPU 4 corresponds to an example of the cooling unit referred to in the present invention.

  If the temperature of the cleaning blade 100C is too low, moisture in the air condenses on the cleaning blade 100C, and the moisture reaches the photoreceptor 61C, which may cause problems such as transfer failure. Therefore, when the CPU 4 detects that the temperature of the cleaning blade 100C has reached 25 ° C. from the measurement result of the current flowing through the thermistor sent from the temperature detection unit 103C, it issues an instruction to the cooling unit 108C, and the cleaning blade 100C. Stop cooling. After the cooling is stopped, when the temperature of the cleaning blade 100C rises as image formation proceeds and the cleaning blade 100C starts to vibrate again at a frequency belonging to the range of 150 Hz to 300 Hz, the cooling unit 108C starts cooling the cleaning blade 100C again. Is done.

  Such control of the CPU 4 maintains a state in which no blade squeal occurs and moisture in the air does not condense on the cleaning blade 100C.

  Here, 25 ° C., which is an average temperature inside the image forming apparatus, is employed as the threshold temperature for stopping the cooling. However, if the temperature is higher than the temperature around the cleaning blade 100C, the moisture in the air is the cleaning blade 100C. Since the condensation does not occur above, the threshold temperature at which the cooling is stopped is not necessarily limited to 25 ° C., and another temperature that matches the temperature around the cleaning blade 100C may be set as the cooling stop threshold temperature. The same components as the cleaning blade 100C, the vibration detection unit 101C, the heat conduction member 102C, the temperature detection unit 103C, and the cooling unit 108C described above are provided in the photoreceptors 61Y, 61M, and 61K, respectively. The cleaning blade is cooled according to the vibration state.

  Hereinafter, it will be described based on specific experimental data that generation of blade squealing is avoided by providing a mechanism for cooling the cleaning blade. In the experiments described below, a developer containing substantially spherical polymer toner particles having a shape factor value (SF) of 110 to 135 and a volume average particle size of 6.5 μm or less was used. Yes.

In this experiment, 47 monochrome images with an image ratio of 1% to 4% are output, and then one color image with an image ratio of 1% to 4% is output for each color of cyan, magenta (M), and yellow (Y). The continuous output of 50 sheets in total is repeated 60 times, and 3000 sheets in total are continuously output. Such an output with an image ratio of 1% to 4% is an output in a situation where the amount of toner used for image formation is very small, and therefore there is insufficient residual toner acting as a lubricant between the cleaning blade and the photosensitive member. It is. In this experiment, the above 3000 sheets are performed under the following two conditions.
(Embodiment) The output test is performed using the image forming apparatus 1000 shown in FIG.
(Comparative Example) The vibration detection unit 101C, the temperature detection unit 103C, and the cooling unit 108C of FIG. 2 are not provided, and the configuration is the same as that of the image forming apparatus 1000 except that the cleaning blade is not cooled. The output test is performed using the image forming apparatus.

  For each of these examples and comparative examples, there are four output periods: 0 to 1500 output periods, 1500 to 2000 output periods, 2000 to 2500 output periods, and 2500 to 3000 output periods. The blade squeaking frequency is examined and the temperature of the cleaning blade is measured. The blade squeaking frequency is evaluated by dividing it into the following categories.

○: Almost no blade squeezing △: Occasional blade squealing ×: Intermittent blade squeaking repeatedly ××: Always blade squeaking Table 1 shows the results of the output test.

  As shown in Table 1, in the comparative example, blade squeal began to occur after 1500 sheets were output when the temperature of the cleaning blade reached 35 ° C., and the cleaning blade temperature was in the range of 35 ° C. to 40 ° C. The blade squeezes occasionally (evaluation is Δ), but the temperature increases as the number of output sheets increases, and the cleaning blade temperature is in the range of 40 ° C. to 45 ° C. during the output period of 2500 to 3000 sheets. When it reaches, intermittent blade squeal occurs repeatedly (evaluation is x). Further, when the temperature of the cleaning blade reaches an area of 45 ° C. to 50 ° C. in the output period of 2500 to 3000 sheets, the blade vibration is more intense as the blade squeals constantly (evaluation is XX). On the other hand, in the example, almost no blade squeal occurred in any of the above four output periods (evaluation was good), and the temperature of the cleaning blade was 25 ° C. to 35 ° C. even after 1500 sheets were output unlike the comparative example. Remains in the ℃ region. This result shows that the cleaning blade is cooled by the cooling unit 108C of FIG. 2 and the temperature rise of the cleaning blade is avoided in the embodiment after the output of 1500 sheets where the blade squeal began to occur in the comparative example. Is reflected. In the embodiment, the temperature of the cleaning blade is not lowered to 25 ° C. or lower, and excessive cooling of the cleaning blade is avoided so that moisture in the air is condensed on the cleaning blade.

  To summarize the results of the above output test, it is concluded that cooling of the cleaning blade before the occurrence of frequent blade squeezing suppresses blade squealing and enables good image formation with low noise. it can.

  In the above description, when it is detected that the temperature of the cleaning blade has reached 25 ° C., cooling of the cleaning blade is stopped and overcooling of the cleaning blade is avoided, but temperature detection is not necessarily required in the present invention. For example, a method of avoiding excessive cooling of the cleaning blade by limiting the cooling of the cleaning blade only to a predetermined time, or an excessive amount of cleaning blade by limiting the amount of power consumed for cooling to a predetermined amount. A method that does not detect temperature, such as a method that avoids cooling, can also be used.

  In the above description, the vibration of the cleaning blade is indirectly detected through the detection of the vibration of the support member. However, in the present invention, the vibration detection unit of FIG. A direct detection method can also be employed. In the above description, the temperature detection unit in FIG. 2 is directly attached to the cleaning blade to detect the temperature of the surface of the cleaning blade. In the present invention, the temperature detection unit in FIG. It is also possible to adopt a method in which the temperature of the cleaning blade surface is indirectly detected through temperature detection of the surface of the support member attached to the support member.

  In the above description, the cooling unit shown in FIG. 2 employs a Peltier element for cooling the cleaning blade. However, in the present invention, in addition to the Peltier element, a cooling blower or the like can be employed.

  Further, although the image forming apparatus of the present embodiment is a full-color image forming apparatus, the image forming apparatus of the present invention may be applied to a monochrome image forming apparatus. In the above description, an example of an image forming apparatus that forms an image via an intermediate transfer belt is shown. However, the present invention directly transfers from a photoreceptor to a recording medium without using an intermediate transfer belt. The present invention may be applied to a direct transfer type image forming apparatus.

1 is an overall configuration diagram of an image forming apparatus according to an exemplary embodiment. FIG. 2 is a diagram illustrating a state of the periphery of a photoreceptor on which a cyan toner image is formed illustrated in FIG. 1. FIG. 3 is a diagram illustrating a vibration detection unit, a temperature detection unit, and a heat conduction member illustrated in FIG. 2 in a plane along the width of the cleaning blade illustrated in FIG. 2.

Explanation of symbols

1000: Image forming apparatus,
1 ... Tray,
2 ... Output tray,
3 ... transport roll,
4 ... CPU,
4K, 4C, 4M, 4Y ... toner cartridge,
5 ... Intermediate transfer belt,
50 ... belt body,
50K, 50C, 50M, 50Y ... primary transfer roll,
5a ... Driving roll,
61Y, 61M, 61C, 61K ... photosensitive member,
64K, 64C, 64M, 64Y ... developer,
65Y, 65M, 65C, 65K ... charger,
7 ... exposure part,
8 ... Registrole vs.
9: Secondary transfer roll pair,
9b ... Secondary transfer roll,
10 ... Fixer,
13: Sending roll pair,
100C ... cleaning blade,
101C ... vibration detection unit,
102C ... heat conducting member,
103C ... temperature detector,
104C ... support member,
105C: Residual toner transport unit,
106C: housing,
107C: residual toner,
108C ... Cooling section

Claims (1)

A developed image is formed on an image carrier, the developed image is transferred from the image carrier onto a recording medium, and the developed image on the recording medium is fixed, whereby an image composed of a fixed image is formed on the recording medium. In the image forming apparatus to be formed,
A cleaning blade that comes into contact with the image carrier , the elastic body having a rebound elastic modulus at 25 ° C. within a range of 20% to 80% and a Young's modulus at 25 ° C. within a range of 70 MPa to 90 MPa ;
A vibration detecting unit for directly or indirectly detecting vibrations of a frequency belonging to the region of 150 Hz to 300 Hz of the cleaning blade;
A cooling unit that cools the cleaning blade when the vibration detecting unit has detected the vibration,
Contacts the front Symbol cleaning blade, the image forming apparatus characterized by comprising a heat conducting member to smooth the temperature distribution of the cleaning blade.

Images