JP2006098818A - Developing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a developing device capable of easily and effectively preventing erroneous detection by a sensor caused by the formation of a bridge due to the change of the fluidity of developer and the adhesion of a foreign matter to a cleaning member. <P>SOLUTION: The developing device 21 includes a casing 5, a cover 6, a 1st stirring screw 7, a 2nd stirring screw 8, a developing roller 11, a regulating blade 12 and a T sensor 13 detecting developer amount. A cleaning member 1 constituted of a coil spring part 1a, a fixed part 1b and a contact-sliding part 1c, rotating in accordance with the rotation of the 1st stirring screw 7, and cleaning the detection surface 13a of the T sensor 13 is provided on the supporting shaft 7a of the 1st stirring screw 7. The T sensor 13 is provided to project from the side wall 5a of the casing 5, and the cleaning member 1 is rotated while repeating the curve and restoration in a state where the contact-sliding part 1c comes into contact with the side surface of the T sensor 13, whereby the detection surface 13a is cleaned by using the elastic force of the contact-sliding part 1c. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a developing device provided with a sensor for detecting the amount of developer, and more particularly to a cleaning member for cleaning a measurement location (sensor detection surface) of the sensor in order to increase detection accuracy.

  In order to maintain the quality of images created by image forming apparatuses such as copiers, printers, and fax machines, the developer is appropriately replenished to the developing device according to the environmental temperature, environmental humidity, etc., and the amount of developer (or The toner density in the developer needs to be adjusted. For this reason, the developing device is usually provided with a detection sensor for measuring the developer amount (or toner concentration).

  However, if the developer containing toner adheres to the measurement location (for example, the detection surface) of the detection sensor, the accurate toner amount inside the developing device cannot be measured. Therefore, various developing devices have been proposed in which a cleaning member is provided in a stirring screw (agitator) inside the developing device, and the detection surface is cleaned in accordance with the rotation of the agitator.

  For example, in the developing device 121 of Patent Document 1 shown in FIG. 8, a single wiper (cleaning member) 101 is provided on the agitator 107, and the detection surface 113 a of the sensor 113 is cleaned according to the rotation of the agitator 107. It has become. However, in this developing device 121, since the flat surface portion 101d of the wiper 101 is positioned perpendicularly (to face) the rotation direction, resistance is given to the rotation of the agitator 107.

  Therefore, as shown in FIG. 9, a developing device 121 that uses a spring member as the cleaning member 101 is considered in order to suppress the resistance given to the rotation of the agitator 107. With such a cleaning member 101, the sliding contact portion 101 c of the cleaning member 101 can clean the detection surface 113 a according to the rotation of the agitator 107, and a single linear sliding contact with respect to the rotation direction of the agitator 107. Since only the portion 101c is positioned vertically (because it is not opposed), the resistance given to the rotation of the agitator 107 can also be suppressed.

  However, in the developing device 121 shown in FIG. 9, the cleaning member 101 rotates in synchronization with the rotation of the agitator 107. However, since the agitator 107 normally rotates at a low speed, the rotation speed of the cleaning member 101 also becomes low, and the fluidity If the deteriorated developer stays in the vicinity of the sensor, the staying developer cannot be dispersed well. In particular, in the case of the one-component development type, if the fluidity of the toner in the developer changes depending on the environmental conditions and the usage period, and it becomes easy to stay (deposit) in the vicinity of the detection surface 113a, there arises a problem of causing false detection of the sensor 113. obtain.

For example, when a developer bridge is formed in the vicinity of the detection surface 113a, or a foreign substance made up of paper dust or fibers and toner aggregates in the development seal portion is caught on the sliding contact portion 101c of the cleaning member 101, and excessive cleaning is performed. In such a case, the sensor 113 may not detect the presence of the developer, and the developing device may be filled with the developer.
Japanese Unexamined Patent Publication No. 2000-250301 (see paragraph [0044], FIGS. 3 and 4)

  SUMMARY OF THE INVENTION In view of the above problems, the present invention provides a developing device that can easily and effectively prevent erroneous detection of a sensor due to bridge formation due to a change in developer fluidity or adhesion of foreign matter to a cleaning member.

  In order to achieve the above object, the present invention provides a housing for storing a developer, detection means provided on a side surface in the housing for detecting the amount of the developer, and a rotary transport unit for stirring and transporting the developer in the housing. And a cleaning member that is provided in the rotary conveyance unit and cleans in contact with the detection surface of the detection means, wherein the cleaning member is a winding spring into which the rotary shaft of the rotary conveyance unit is inserted And a fixed portion that is formed by bending one end of the winding spring portion and is fixed to the rotating shaft, and a sliding contact portion that is formed by extending the other end of the winding spring portion and contacts the detection surface. The sliding contact portion is in contact with a side surface of the detecting means that protrudes from the side surface of the housing as the rotary conveyance portion rotates, and rotates while repeating bending and restoring.

  According to the present invention, in the developing device configured as described above, the sliding contact portion extends linearly in a tangential direction of the winding spring portion, and the winding direction of the winding spring portion is from the fixed portion to the sliding contact portion. When viewed in this direction, the rotation direction is the same as the rotation direction of the rotary conveyance unit.

  According to the present invention, in the developing device having the above-described configuration, the tip of the sliding contact portion is bent at an acute angle on the upstream side in the rotation direction of the rotary conveyance unit.

  According to the present invention, in the developing device configured as described above, the protruding amount of the detecting unit is approximately the same as the thickness of the sliding contact portion.

  According to the present invention, in the developing device configured as described above, the detection means is a piezoelectric element.

  According to the first configuration of the present invention, the winding spring portion into which the rotation shaft of the rotation conveyance portion is inserted, the fixing portion formed by bending one end of the winding spring portion and fixed to the rotation shaft, and the other end are connected. In a developing device that cleans the detection surface of the detection means using a cleaning member that extends and contacts the detection surface, the detection means protrudes from the side surface of the housing, and the sliding contact portion of the cleaning member However, it is detected by the momentum and vibration of the slidable contact part that separates from the side surface of the detecting means by elastic force by contacting the side surface of the detecting means with the rotation of the rotation conveyance section and rotating while repeating the bending and restoring. The developer bridge generated in the vicinity of the surface can be effectively broken.

  According to the second configuration of the present invention, in the developing device of the first configuration, one end of the winding spring portion is linearly extended in the tangential direction to form a sliding contact portion, and the sliding portion direction from the fixed portion When the winding direction of the winding spring portion is viewed in the same direction as the rotation direction of the rotary conveyance unit, the portion close to the tip of the sliding contact portion comes into contact with the side surface of the detection means. It becomes easy to be hooked on the sliding portion, and the locking and detachment of the sliding contact portion is stabilized.

  According to the third configuration of the present invention, in the developing device according to the first or second configuration, the elastic force is obtained by bending the tip of the sliding contact portion at an acute angle upstream in the rotation direction of the rotary conveyance unit. As a result, the foreign matter or the like attached to the tip of the sliding contact portion can be easily removed at a moment when the sliding contact portion is detached from the detection means.

  According to the fourth configuration of the present invention, in the developing device having any one of the first to third configurations, the amount of protrusion of the detection unit is set to be approximately the same as the thickness of the sliding contact portion. As a result, the cleaning effect of the cleaning member is stabilized and the sliding contact portion is not excessively loaded, so that the cleaning member is not likely to be damaged.

  Further, according to the fifth configuration of the present invention, in the developing device of any one of the first to fourth configurations, the presence of the developer can be detected more accurately by using the detection means as a piezoelectric element. The amount of developer in the developing device can be further stabilized.

  Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows an image forming apparatus (for example, a printer) 69 using the developing device 21 of the present invention. The image forming apparatus 69 includes a photosensitive drum 41, a charging unit 42, an image writing unit (laser scanning unit) 43, a developing device 21, a toner storage unit 44, a transfer unit 45, a cleaning unit 46, a sheet storage unit 51, a conveyance unit. The unit 52 includes a fixing unit 53, and a paper discharge unit 54.

  The photosensitive drum 41 is formed, for example, by laminating a photosensitive layer on an aluminum drum, and the charging unit 42 charges the surface. Then, an electrostatic latent image in which charging is attenuated is formed on the surface that has received the laser beam from the image writing unit 43. The photosensitive layer is not particularly limited, but for example, amorphous silicon (a-Si) having excellent durability is preferable.

  The charging unit (charging charger) 42 charges the surface of the photosensitive drum 41 by discharging (for example, corona discharge). For example, the charging unit 42 has a thin wire or the like, and uses this as an electrode to discharge when a high voltage is applied.

  The image writing unit (LSU) 43 irradiates the photosensitive drum 41 with a light beam (for example, a laser beam) based on the image data, and forms an electrostatic latent image on the photosensitive drum 41. The image data is transmitted from a personal computer (PC) (not shown).

  The developing device 21 attaches toner to the electrostatic latent image on the photosensitive drum 41 to form a toner image. Examples of the developer accommodated in the developing device 21 include a two-component developer composed of toner and carrier and a one-component developer composed only of toner. Details of the developing device 21 will be described later.

  The toner storage unit (hopper) 44 supplies the developer to the developing device 21 and stores the developer when the developer in the developing device 21 becomes insufficient.

  The transfer unit 45 transfers the toner image formed on the surface of the photoconductive drum 41 to the conveyed sheet without disturbing the toner image.

  The cleaning unit 46 removes the toner (residual toner) remaining on the surface of the photosensitive drum 41 after the toner image is transferred (transferred) to the sheet. For example, a blade material that makes line contact with the longitudinal direction of the photosensitive drum 41 may be used.

  The sheet storage unit 51 stores a sheet (paper, OHP, etc.) on which an image (toner image) is finally printed, and sends the sheet to the transport unit 52.

  The conveyance unit 52 is a sheet path from the sheet storage unit 51 to the paper discharge unit 54. The fixing unit 53 converts the toner image transferred onto the sheet into a stable permanent image. For example, the fixing unit 53 melts the powder toner image by applying energy such as heat or pressure.

  The paper discharge unit 54 accommodates a sheet that has passed through the fixing unit 53, that is, a sheet on which a permanent image is printed and discharged to the outside of the apparatus.

  In such an image forming apparatus 69, the LSU 43 emits a laser beam (light beam) to the photosensitive drum 41 based on the image data, so that the electrostatic latent image based on the image data is displayed on the photosensitive drum 41. Form on the surface. Thereafter, the developing device 21 attaches toner to the electrostatic latent image (forms a toner image), and the transfer unit 45 transfers the toner image to the sheet. Next, the fixing unit 53 applies heat or the like to the sheet onto which the toner image has been transferred to form a permanent image.

  Next, the configuration of the developing device 21 will be described. 2 is a schematic perspective view of the developing device 21 of the present invention, FIG. 3A is a schematic side view, and FIG. 3B is a schematic plan view from above. 2 and 3 (b) are expressed excluding the lid portion (cover portion) for convenience, and FIG. 3 (a) expresses the first stirring screw 7 described later with emphasis.

  As shown in these drawings, the developing device 21 includes a casing (housing) 5, a cover (housing) 6, a first agitation screw (rotary conveyance unit) 7, a second agitation screw (rotary conveyance unit) 8, and development. The configuration includes a roller 11, a regulation blade 12, and a toner amount detection sensor (hereinafter referred to as a T sensor) 13.

  The casing 5 stores the developer and accommodates the first stirring screw 7 and the like. And in this casing 5, the 1st storage chamber 15 and the 2nd storage chamber 16 which were divided by the partition plate 9 are formed, and the 1st stirring screw 7 is 2nd in the 1st storage chamber 15. A second stirring screw 8 is disposed in the storage chamber 16. The cover 6 is sealed so that the developer accommodated in the casing 5 does not leak outside. The casing 5 and the cover 6 together constitute a housing of the developing device 21. Note that FIG. 3A showing the cover 6 represents a state where the cover 6 and the casing 5 are dissociated.

  The first stirring screw 7 conveys the developer stored in the first storage chamber 15 in the direction of arrow P while stirring the developer, and guides it to the second storage chamber 16. The developer transported to the second storage chamber 16 is transported in the direction of arrow Q while being agitated and supplied to the developing roller 11.

  The first agitating screw 7 and the second agitating screw 8 have a structure in which spiral blades 7b and 8b are provided around the support shafts 7a and 8a, respectively. It is pivotally supported so that it can rotate.

  The developing roller 11 supplies toner to the photosensitive layer of the photosensitive drum 41 by rotating in accordance with the rotation of the photosensitive drum 41 (see FIG. 1). In the case of a developing device using a magnetic developer, a magnet roller having a magnetic field generating member (not shown) made of a permanent magnet fixed on the inner surface is used as the developing roller 11. A toner thin layer is formed by attaching (carrying) toner to the surface of the developing roller 11 by the magnetic force of the magnetic field generating member. On the other hand, in the case of a developing device using a non-magnetic developer, a rubber roller or the like is used as the developing roller 11.

  The developing roller 11 is rotatably supported on the casing 5 in a state parallel to the first stirring screw 7 and the second stirring screw 8. The first stirring screw 7, the second stirring screw 8, and the developing roller 11 are rotationally driven by driving means (not shown).

  The regulating blade 12 regulates the amount of toner supplied to the photosensitive drum 41, and in the case of a developing device using a magnetic developer, SUS (stainless steel) such as SUS430 is used. A magnetic field generating member provided opposite to the tip of the regulating blade 12 generates a magnetic field between the developing roller 11 and the regulating blade 12, and not only the distance between the regulating blade 12 and the developing roller 11 but also the magnetic field. The amount of toner adhering to the developing roller 11 is strictly regulated by the strength. This makes it possible to form a thin toner layer of several tens of microns.

  The T sensor 13 is a sensor (piezoelectric sensor) made of a piezoelectric element, for example, and detects the amount of developer (or toner concentration) in the casing 5. Piezoelectric sensors use the property of piezoelectric elements that generate a voltage proportional to the magnitude of an impact or vibration from the outside, taking out the impact or vibration as an electrical signal. Has features. The T sensor 13 is provided on the side wall 5 a of the casing 5 in the vicinity of the communication between the first storage chamber 15 and the second storage chamber 16. The T sensor 13 is provided such that a detection surface 13a, which will be described later, faces the first storage chamber 15 and the second storage chamber 16, that is, the inner side.

  When the developer is sufficiently stored in the first storage chamber 15 and the second storage chamber 16, the detection surface 13 a of the T sensor 13 is sufficiently applied with the developer by being applied with a constant pressure by the developer. It is detected that it is stored in On the other hand, when a sufficient amount of developer is not stored in the first storage chamber 15 and the second storage chamber 16, the T sensor 13 is not applied with a pressure higher than a certain level by the developer. In such a case, the T sensor 13 detects that the developer amount is not sufficient.

  When it is detected by the T sensor 13 that the developer is sufficiently stored, a detection signal is transmitted to a control unit such as a CPU provided in the image forming apparatus, and the control unit stores the toner storage unit 44 (FIG. 1). The supply of the developer into the developing device 21 is stopped. When the developer amount in the developing device 21 decreases and the developer does not contact the detection surface 13a, the control unit resumes the supply of the developer from the toner storage unit 44.

  In the above description, the piezoelectric sensor is used. However, the sensor used in the developing device 21 of the present invention is not limited to the piezoelectric sensor. For example, an optical sensor or a magnetic sensor may be used. Further, the developer used in the developing device 21 of the present invention is not particularly limited, and may be a one-component developer or a two-component developer, and further, a magnetic method or a non-magnetic method. It doesn't matter.

  Here, a characteristic configuration of the developing device 21 of the present invention will be described. In the developing device 21, a cleaning member 1 including a winding spring portion 1 a, a fixing portion 1 b, and a sliding contact portion 1 c is provided on the support shaft 7 a of the first stirring screw 7. The cleaning member 1 also rotates in accordance with the rotation of 7, and the detection surface 13 a of the T sensor 13 is cleaned. Further, the T sensor 13 is provided so as to protrude from the side wall 5a of the casing 5, and the sliding contact portion 1c comes into contact with the side surface of the T sensor 13 and rotates while repeatedly curving and restoring. The detection surface 13a is cleaned using an elastic force.

  FIG. 4 shows the configuration of the cleaning member 1 used in the developing device of the present invention. 4 (a) is a perspective view of the cleaning member 1, FIGS. 4 (b) and 4 (c) are side views of the cleaning member 1, and FIG. 4 (d) is a plan view of FIG. 4 (b) viewed from the direction of arrow A. It is. The cleaning member 1 includes a wound spring portion 1a, a fixing portion 1b, and a sliding contact portion 1c that are integrally formed using a single metal wire (spring material) having elasticity. The winding spring part 1a is a part for attaching the cleaning member 1 to the support shaft 7a (see FIG. 2) of the first stirring screw 7, and the support shaft 7a penetrates the inside thereof.

  The fixing part 1b transmits the rotational force of the first stirring screw 7 (see FIG. 2) to the cleaning part 1, and is formed by extending one end of the winding spring part 1a in the tangential direction and bending it twice at a right angle, It is adapted to be locked to the spiral wing 7b (see FIG. 2).

  The slidable contact portion 1c is slidably contacted (slidably contacted) with the detection surface 13a of the T sensor 13, and the other end of the winding spring portion 1a not provided with the fixed portion 1b is extended in the tangential direction to support the shaft. It is formed in a pin shape having a length that includes the entire area (diameter) of the detection surface 13a from 7a.

  Further, since the side wall 5a of the casing 5 and the spiral wing 7b (see FIG. 2) are positioned with respect to the expansion / contraction direction of the winding spring portion 1a, the length of the winding spring portion 1a is changed from the side wall 5a to the spiral wing 7b. If it is formed longer than this distance, the winding spring portion 1a is sandwiched between the side wall 5a and the spiral blade 7b, and the sliding contact portion 1c is pushed toward the side wall 5a by the urging force of the winding spring portion 1a ( Pressed). As a result, the slidable contact portion 1c is disposed close to the side wall 5a of the casing 5 so as to be able to slidably contact the detection surface 13a.

  Here, as shown in FIG. 4C, the tip of the sliding contact portion 1c is bent at a predetermined angle (here, 45 °) from the side wall 5a so as not to damage the side wall 5a. It is preferable. In addition, by providing such a bent portion, an effect of widening the cleanable area around the detection surface 13a can be expected.

  Further, since the rotation direction of the cleaning member 1 is the arrow B direction, as shown in FIG. 4D, the tip of the sliding contact portion 1c has an acute angle (45 in this case) on the upstream side in the rotation direction (the direction opposite to the arrow B). B). As a result, when the sliding contact portion 1c is hooked on the side surface of the T sensor 13 and is bent, the foreign matter attached to the tip of the sliding contact portion 1c slips through and easily comes off when it is vigorously restored by the elastic force. That is, it is preferable that the tip of the sliding contact portion 1c be bent inward from the detection surface 13a and at an acute angle upstream in the rotational direction.

  Further, it is preferable that the winding direction of the winding spring portion 1 a viewed in the direction from the fixed portion 1 b to the sliding contact portion 1 c (arrow A direction) is the same direction as the rotation direction of the first stirring screw 7. Since the sliding contact portion 1c extends in the tangential direction of the winding spring portion 1a, when the winding direction of the winding spring portion 1a is opposite to the rotation direction, as shown in FIG. The side of the T sensor 13 is first contacted from the root portion (portion close to the winding spring portion 1a). For this reason, a relatively large force is required to bend the sliding contact portion 1c, and the sliding contact portion 1c is detached from the side surface of the T sensor 13 before it is sufficiently curved.

  On the other hand, when the winding direction of the winding spring portion 1a is the same as the rotation direction, as shown in FIG. 5 (b), the side close to the tip of the sliding contact portion 1c contacts the side surface of the T sensor 13 first. Therefore, the sliding contact portion 1c can be bent with a relatively small force. That is, after the sliding contact portion 1c is sufficiently curved, it is released from the side surface of the T sensor 13 with a restoring force, so that the vicinity of the detection surface 13a can be effectively cleaned using the elasticity of the sliding contact portion 1c. . Here, since the rotation direction of the cleaning member 1 is the arrow B direction (counterclockwise), the winding direction of the coil spring 1a is counterclockwise (counterclockwise).

  Next, the manner in which the cleaning member 1 repeatedly contacts and separates from the side surface of the T sensor 13 to clean the sensor surface 13a will be described with reference to FIGS. FIG. 6 is a drawing based on FIG. 3 (a), which mainly expresses the sliding contact portion 1c of the cleaning member 1 and the support shaft 7a of the first stirring screw 7. FIG. ), And the winding spring portion 1a, the sliding contact portion 1c, and the support shaft 7a are intensively expressed. In both cases, the fixed portion 1b and the spiral feather 7b are not shown.

  FIGS. 6A and 7A show a state in which the sliding contact portion 1c is rotated according to the rotation of the support shaft 7a after cleaning the detection surface 13a. 6 (b) and 7 (b), the sliding contact portion 1c further rotates from the state of FIGS. 6 (a) and 7 (a), and immediately before the detection surface 13a of the T sensor 13 is cleaned. Indicates the state. As shown in the figure, since the T sensor 13 protrudes from the side wall 5 a, the sliding contact portion 1 c comes into contact with the side surface of the T sensor 13.

  FIG. 6C and FIG. 7C show a state where the sliding contact portion 1 c is in contact with the side surface of the T sensor 13. While the sliding contact portion 1c is locked by the side surface of the T sensor 13, the winding spring portion 1a and the fixed portion 1b continue to rotate together with the support shaft 7a, so that the sliding contact portion 1c curves against the elastic force (see FIG. 6 (c)).

  As the rotation continues further, as shown in FIGS. 6D and 7D, the sliding contact portion 1c gets over the side surface of the T sensor 13 by the elastic force (restoring force) accumulated by the bending. It detaches vigorously and oscillates for a while due to inertial force after sliding on the detection surface 13a. Thereby, even when a bridge is generated in the vicinity of the detection surface 13a, the developer bridged by the sliding contact and vibration of the sliding contact portion 1c can be broken. And it returns to the state of Fig.6 (a) and FIG.7 (a) again, and repeats said operation | movement.

  As described above, in the developing device 21 of the present invention, the detection surface 13a of the T sensor 13 provided in the casing 5 storing the developer is moved by the sliding contact portion 1c of the cleaning member 1 provided in the first stirring screw 7. It is supposed to be cleaned. In particular, the T sensor 13 is provided so as to protrude from the side wall 5 a of the casing 5, and after the sliding contact portion 1 c of the cleaning member 1 is hooked on the side surface of the T sensor 13 and curved, it is restored by elastic force and It has come off from the side vigorously.

  As a result, even if the flowability of the developer changes depending on the environmental conditions and the usage period and it becomes easy to stay in the vicinity of the detection surface 13a, the sliding contact portion 1c vibrates and vibrates vigorously. The occurrence of bridging can be surely prevented. Further, since the sliding contact portion 1c is in sliding contact with the detection surface 13a for a short time, the developer detection sensitivity of the T sensor 13 is improved. Therefore, erroneous detection of the T sensor 13 can be prevented.

  Further, it is preferable that the amount of protrusion of the T sensor 13 from the side wall 5a is approximately the same as the thickness of the sliding contact portion 1c. When the protruding amount is smaller than the thickness of the sliding contact portion 1c, it is not locked to the side surface of the T sensor 13 until the sliding contact portion 1c is sufficiently curved, and a restoring force for slidably contacting the detection surface 13a can be accumulated. Disappear. On the other hand, if the protruding amount is larger than the thickness of the sliding contact portion 1c, the sliding contact portion 1c cannot be detached from the side surface of the T sensor 13 even if the first stirring screw 7 rotates, and the sliding contact portion 1c or the winding spring portion 1a. The cleaning member 1 may be deformed or damaged due to an excessive load. Since the cleaning member 1 is integrally formed using one wire, the protruding amount of the T sensor 13 may be appropriately set according to the thickness of the wire forming the cleaning member 1. For example, in the above embodiment, when the cleaning member 1 is formed using a wire having a diameter of 0.5 mm, the protrusion amount of the T sensor 13 is optimally about 0.5 mm.

  The present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention. For example, the cleaning member 1 may be attached to the second stirring screw 8 as long as the detection surface 13a of the T sensor 13 can be cleaned. Further, the installation position of the T sensor 13 is not particularly limited as long as the developer amount in the casing 5 can be accurately detected.

  The present invention provides a housing for storing the developer, a detection unit provided on a side surface in the housing for detecting the amount of the developer, a rotating transport unit for stirring and transporting the developer in the housing, and the rotating transport unit. And a cleaning member that contacts and cleans the detection surface of the detection means, and the cleaning member includes a winding spring portion into which the rotation shaft of the rotation conveyance portion is inserted, and one end of the winding spring portion. It consists of a fixed part that is bent and fixed to the rotating shaft, and a slidable contact part that is formed by extending the other end of the winding spring part and contacts the detection surface. Suppose that it contacts the side surface of the detection means provided protruding from the side surface of the housing, and rotates while repeating the bending and restoring.

  As a result, even if the developer changes its fluidity depending on the environmental conditions and the period of use and becomes easy to stay in the vicinity of the detection surface, it is curved while being curved at the side of the detection means and then rotated while being restored by elastic force. A developing device that effectively prevents the occurrence of a bridge in the vicinity of a detection surface by virtue of the sliding contact portion and vibration. Moreover, since the time for which the sliding contact portion is in sliding contact with the detection surface is short, the detection sensitivity of the detection means is improved and erroneous detection can be prevented.

  Further, one end of the winding spring portion is linearly extended in the tangential direction to form a sliding contact portion, and the winding direction of the winding spring portion viewed from the fixing portion in the sliding contact portion direction is set in the same direction as the rotation direction of the rotary conveying portion. Therefore, the portion close to the tip of the sliding contact portion comes into contact with the side surface of the detection means, so that the sliding contact portion is easily caught by the detection means, and the cleaning operation of the detection surface by the sliding contact portion is further stabilized.

  In addition, since the tip of the sliding contact portion is bent at an acute angle upstream in the rotation direction of the rotary conveyance portion, foreign matter or the like attached to the tip of the sliding contact portion is easily removed.

  Further, since the protruding amount of the detecting means is set to be approximately the same as the thickness of the sliding contact portion, the locking of the sliding contact portion to the detecting means is ensured, the cleaning effect by the cleaning member is stabilized, and the sliding contact portion is excessively moved. Therefore, there is no possibility that the cleaning member is damaged.

FIG. 1 is a schematic configuration diagram of an image forming apparatus including a developing device of the present invention. These are the schematic perspective views of the image development apparatus of this invention. These are a schematic side view of the developing device of the present invention (FIG. 3A) and a schematic plan view seen from above (FIG. 3B). FIG. 4A is a perspective view (FIG. 4A), a side view (FIGS. 4B and 4C), and a plan view (FIG. 4D) of a cleaning member used in the developing device of the present invention. These are explanatory drawings which show the relationship between the contact state to the side surface of the T sensor of a sliding contact part, and the winding direction of a winding spring part. Fig. 3A is a drawing based on Fig. 3A, in which Fig. 3A shows a state where the sliding contact portion is rotated after cleaning the detection surface, and Fig. 3B shows that the sliding contact portion further rotates and cleans the detection surface. (C) is an explanatory view showing a state in which the slidable contact portion is in contact with the side surface of the T sensor and is curved, and (d) is an explanatory view showing a state in which the slidable contact portion is detached from the side surface of the T sensor. FIG. 3B is a drawing based on FIG. 3B, in which FIG. 3A is a state where the sliding contact portion is rotated after cleaning the detection surface, and FIG. 3B is a state where the sliding contact portion is further rotated to clean the detection surface. (C) is an explanatory view showing a state in which the slidable contact portion is in contact with the side surface of the T sensor and is curved, and (d) is an explanatory view showing a state in which the slidable contact portion is detached from the side surface of the T sensor. These are schematic plan views showing a conventional developing device. FIG. 9 is a schematic plan view showing another example of FIG. 8.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Cleaning member 1a Winding spring part 1b Fixed part 1c Sliding contact part 5 Casing (housing | casing)
5a Side wall 6 Cover (housing)
7 1st stirring screw (rotary conveyance part)
7a Support shaft (rotary transfer part)
8 Second agitation screw (rotary conveyance part)
8a Spindle (Rotating conveyance part)
9 Partition plate 11 Developing roller 12 Regulating blade 13 T sensor (detection means)
13a Detection surface 15 First storage chamber 16 Second storage chamber 21 Developing device 69 Image forming device

Claims (5)

A housing for storing the developer, a detecting means provided on a side surface in the housing for detecting the amount of the developer, a rotary transport unit for stirring and transporting the developer in the housing, and the rotational transport unit provided in the rotary transport unit; In a developing device comprising a cleaning member that contacts and cleans the detection surface of the detection means,
The cleaning member includes a winding spring portion into which the rotation shaft of the rotation conveyance portion is inserted, a fixing portion formed by bending one end of the winding spring portion and fixed to the rotation shaft, and the other end of the winding spring portion. A sliding contact portion that is formed by extending and contacting the detection surface,
The developing device according to claim 1, wherein the sliding contact portion is in contact with a side surface of the detection unit provided so as to protrude from the side surface of the housing as the rotation conveyance unit rotates, and rotates while repeatedly bending and restoring.   The sliding contact portion extends linearly in the tangential direction of the winding spring portion, and the winding direction of the winding spring portion is the rotation of the rotary conveying portion when viewed from the fixed portion toward the sliding contact portion. The developing device according to claim 1, wherein the developing device is in the same direction as the direction.   3. The developing device according to claim 1, wherein a tip end of the sliding contact portion is bent at an acute angle upstream in a rotation direction of the rotary conveyance unit.   The developing device according to claim 1, wherein a protruding amount of the detection unit is approximately the same as a thickness of the sliding contact portion.   The developing device according to claim 1, wherein the detection unit is a piezoelectric element.

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