JP2006154303A - Developing unit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To detect the developer without being influenced by the outer impairments such as noise. <P>SOLUTION: This developing unit has a reservoir 260 to store the developer, and a sensing means 300 attached on the inner wall of the reservoir 260. The sensing means 300 has a sound wave generator 310 and a receiver 320. A cover 400 is provided around the sound wave generator 310 to reflect the sound wave. The receiver 320 receives the sound wave outputted by the sound wave generator 310 and senses the developer in the reservoir 260. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a developing device applied to an image forming apparatus such as a printer or a plotter, and more particularly to a developing device that detects a developer.

  As a configuration for detecting the developer contained in the developing device, there is a light transmission type configuration. In this configuration, a light emitting unit and a light receiving unit are arranged with a developer container containing the developer interposed therebetween. Furthermore, windows that transmit light are provided at positions where the light emitting unit and the light receiving unit face each other.

  When the developer container is filled with the developer, light from the light emitting portion is blocked by the developer and does not reach the light receiving portion. When the developer is consumed and the developer runs out of light, the light from the light receiving unit reaches the light receiving unit through the light path. In this way, the light receiving unit also detects the remaining amount of developer based on the change in output. However, this configuration has problems such as dust adhering to the light emitting part and the light receiving part, and a decrease in detection accuracy due to a temporal change of the light emitting part and the light receiving part.

In order to solve this problem, there is a configuration as in Patent Document 2. In this configuration, the residual test speaker 101 and the residual test microphone 102 are attached to the developer container 10, sound waves are emitted from the residual test speaker 101 toward the developer container 10, and the acoustic waves are detected by the residual test microphone 102. To do.
JP-A-11-167268

  However, the above configuration utilizes a phenomenon that the wavelength of the acoustic sound wave changes with a change in the free volume in the developer container, and detects the amount of the developer, so that a drive source for driving the apparatus main body ( There is a risk that noise such as noise from a motor or the like will be picked up and detection accuracy will be reduced.

  In order to solve the above problems, the present invention has a storage unit for storing the developer, and a detection unit attached to the inner wall surface of the storage unit, the detection unit includes a sound wave generation unit and a reception unit, A cover for reflecting the sound wave of the sound wave generator to the receiving side is provided around the sound wave generator, and the receiver receives the sound wave output from the sound wave generator, thereby developing the developer in the storage unit. Is detected. According to a second aspect of the present invention, the sound wave generator is disposed at a position where the developer is not buried in the developer, and the receiver is disposed at a position where the developer must be supplied.

  According to a third aspect of the present invention, the sound wave generator is disposed at a position where the developer must be supplied, and the receiver is disposed at a position where the receiver is not buried in the developer. According to a fourth aspect of the present invention, a notch portion is provided below the cover portion. According to a fifth aspect of the present invention, the notch portion of the cover portion is provided with a stay prevention means for preventing the developer from staying in the cover portion. According to a sixth aspect of the present invention, the retention preventing means includes a rotating shaft and a stirring portion attached to the rotating shaft.

  The present invention has a storage unit for storing the developer, and a detection unit attached to the inner wall surface of the storage unit, the detection unit includes a sound wave generation unit and a reception unit, around the sound wave generation unit, A cover for reflecting the sound waves of the sound wave generator to the receiving side is provided, and the receiver detects the developer in the storage unit by receiving the sound waves output from the sound wave generator. According to a second aspect of the present invention, the sound wave generator is disposed at a position where it is not buried in the developer, and the receiver is disposed at a position where the developer must be supplied, so that it is not affected by disturbance due to noise or the like. In addition, the developer can be detected.

  A preferred embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a schematic sectional view of the developing device of the present invention. In the illustrated apparatus, the developer is supplied from a developer replenishing device described later. The developer supply device 100 includes a developer container 110 and a conveying unit 130 that are arranged in parallel in two or more. One developer container 110 may be provided. Further, this developing device is of a cleanerless contact developing system using a non-magnetic one-component developer.

  Each developer container 110 is translucent so that the remaining amount of the developer can be visually confirmed, and includes a transport blade (not shown) for sending the developer in the developer container 110. Each developer container 110 is formed in the same shape so that the number of types of containers can be reduced, and cost reduction and recyclability can be improved.

  The conveying means 130 is formed in the shape of a hollow pipe extending from the place where each developer container 110 is arranged to the developing device side, and a screw member 131 is provided therein. A part of the shaft of the screw member 131 protrudes from the conveying means 130 and is connected to a drive source (not shown). Further, the developer supplied from the developer supply device 100 is conveyed to the supply pipe 210 through the conveyance hole 120. The developer conveyed to the supply pipe 210 is stored in the storage unit 260 of the developing device 200. The storage unit 260 is attached to the frame of the developing device 200.

  The developing device 200 includes a supply pipe 210, a developer carrier 220, a layer thickness regulating unit 230, a developer supply unit 240, and a stirring unit 250. These are arranged in the storage unit 260. The supply pipe 210 conveys the developer supplied from the developer supply device 100 to the stirring means 250 side. As shown in FIGS. 1 and 2, the developer carrier 220 supplies the developer to the electrostatic latent image formed on the electrostatic latent image carrier 270, and is a conductive rigid body such as stainless steel. An elastic intermediate layer 222 is formed around a central axis 221 made of Further, an elastic surface layer 223 is formed on the outer periphery of the elastic intermediate layer 222. The developer carrier 220 rotates counterclockwise, and the center shaft 221 is connected to a power source (not shown).

  The layer thickness regulating means 230 regulates the layer thickness of the developer supplied in a layer form on the developer carrier 220 by the developer supply means 240. As seen from the rotation direction of the developer carrier 220, the developer carrier 220 includes a conductive or semiconductive rotatable roller disposed upstream of the contact portion between the developer carrier 220 and the electrostatic latent image carrier 270. Rotate clockwise. Further, a scraping member 231 that scrapes off the developer adhering to the surface of the layer thickness regulating means 230 is provided at an appropriate location of the layer thickness regulating means 230.

  The developer supply means 240 is disposed in parallel with the axis of the developer carrier 220. Further, the developer supply means 240 includes a central shaft 241 extending in the same direction as the axis of the developer carrier 220 and a stirring blade 242 formed on the central shaft 241 in a screw shape in the axial direction. The stirring blade 242 rotates in the clockwise direction. Further, the stirring means 250 provided behind the developer supply means 240 has the same configuration as the developer supply means 240.

  Similar to the developer supply means 240, two stirring means 250 are arranged in parallel with the axis of the developer carrier 220. Between each stirring means (250a, 250b), each stirring means (250a, 250b) is partitioned, and further, the developer transported from the supply pipe 210 is transported to each stirring means 250. A partition plate 251 is provided. The partition plate 251 is provided with a communication hole 252 so that the developer conveyed from the supply pipe 210 and the developer in the developer supply means 240 and the stirring means (250a, 250b) can be circulated.

  A detection unit 300 is provided on the inner wall of the storage unit 260. The detection unit 300 detects the remaining amount of the developer in the storage unit 260, and includes a sound wave generation unit 310 that outputs a sound wave having a certain characteristic and a reception unit 320 that receives the sound wave. In this embodiment, the sound wave generator 310 is a speaker, and the receiver 320 is a microphone.

  As shown in FIGS. 1 and 2, the sound wave generation unit 310 and the reception unit 320 are disposed substantially at the center when viewed from the width of the stirring means 250. In addition, the sound wave generator 310 is disposed above the receiver 320. Further, the receiving unit 320 is arranged at a position where the developer must be supplied. Thereby, when the storage unit 260 is filled with the developer, the receiving unit 320 is always in a state of being buried in the developer. In this embodiment, the sound wave generation unit 310 is disposed above the reception unit 320, but the reception unit 320 may be disposed above the sound wave generation unit 310.

  Further, in order to prevent external noise, for example, operation sound of each means constituting the apparatus, by the reception unit 320, and to prevent erroneous detection, the sound wave generation unit 310 outputs sound waves at a specific frequency, and the reception unit Reference numeral 320 can receive a sound wave output from the sound wave generator 310.

  In addition, a cover unit 400 is provided in the space of the storage unit 260 in which the sound wave generation unit 310 and the reception unit 320 are arranged. This is because, when the cover unit 400 is not provided, the sound wave output from the sound wave generation unit 310 may detect the developer supply unit 240, the developer carrier 220, and the developer present in these regions. For this reason, by reflecting the sound wave output from the sound wave generation unit 310 in a limited space, the reception unit 320 can improve the reception of the sound wave from the sound wave generation unit 310.

  The cover part 400 is formed in a box shape and closes a part of the stirring unit 250a, the sound wave generation part 310, and the reception part 320. Further, a cutout portion is provided on the lower side of the cover portion. The notch is formed so that when the developer replenished from the developer replenishing device 100 or the developer in the storage unit 260 is stirred by the stirring means 250, the developer passes through the receiving surface on the receiving unit 320 side. ing.

  In this embodiment, the notch 410 has a gap S in the vertical direction that is gradually seen from the axial direction of the stirring means 250a as it goes in the rotation direction of the stirring means 250a so that the developer can be easily introduced into the cover 400. Is formed to be wide.

  With this configuration, the remaining amount position of the developer inside the cover unit 400 is the same position as the remaining amount position of the developer stored in the storage unit 260. Further, when the developer is consumed, the remaining amount position of the developer in the cover unit 400 becomes lower following the remaining amount position of the developer stored in the storage unit 260.

  Further, the notch 410 of the cover part 400 is provided with a stay prevention means 500 (not shown in FIG. 2) so that the developer conveyed from the stirring means 250a does not stay in the cover part 400. . This is because if the developer stays in the cover unit 400, the remaining amount position of the developer in the cover unit 400 and the remaining amount position of the developer stored in the storage unit 260 are different. This is to prevent the remaining amount of the agent from being detected.

  The stay prevention means 500 includes a rotating shaft 510 and a stirring portion 520 having a polyester film or the like attached to the rotating shaft 510. The stay prevention means 500 is caused to stay in the cover part 400 by rotating the rotating shaft 510 in a predetermined direction by an independent drive source (not shown) or a drive source (not shown) such as the stirring means 250. The developer is discharged.

  Next, the detection of the developer of the present invention will be described with reference to FIGS. As shown in FIG. 2, when the developer is supplied to the storage unit 260 such as when the developer is supplied from the developer supply device 100 via the supply pipe 210, the reception unit 320 is caused by the developer. It becomes buried. Accordingly, the receiving unit 320 detects that the storage unit 260 is filled with the developer because the receiving unit 320 does not receive the sound wave of the sound wave generating unit 310.

  Further, when the developer is gradually consumed, for example, the state shown in FIG. 3 is changed to the state shown in FIG. During this time, the cleaning unit 500 operates for a predetermined time at regular intervals, and cleans the reception surface of the reception unit 320. As the developer is consumed, the receiving surface of the receiving unit 320 appears. As a result, the receiving unit 320 can receive the sound wave of the sound wave generating unit 310, and by detecting the sound wave, the storage unit 260 detects that there is no developer. When it is detected that there is no developer in the storage unit 260, a control unit (not shown) operates the developer supply device 100 to supply the developer to the storage unit 260.

  As described above, in order to detect the presence or absence of the developer in the storage unit 260 of the developing device 200 based on whether or not the sound wave generation unit 310 outputs a sound wave of a specific frequency and the reception unit 320 receives the sound wave. The developer can be detected without being affected by disturbance due to noise or the like.

Schematic of the developing device of the present invention The figure which looked at FIG. 1 from arrow A The figure with which the storage part was filled with the developer. FIG. 4 is a diagram in which the developer in the storage unit is consumed from the state of FIG. 3 and the receiving unit is exposed.

Explanation of symbols

110 Developer container 220 Developer carrier 260 Storage unit 300 Detection unit 310 Sound wave generation unit 320 Reception unit 400 Cover unit

Claims (6)

A storage unit for storing the developer, and a detection means attached to the inner wall surface of the storage unit;
The detection means includes a sound wave generator and a receiver.
Around the sound wave generation unit, a cover part for reflecting the sound wave of the sound wave generation unit to the reception side is provided,
The developing device according to claim 1, wherein the receiving unit detects the developer in the storage unit by receiving the sound wave output from the sound wave generating unit.   The developing device according to claim 1, wherein the sound wave generation unit is disposed at a position where the developer is not buried in the developer, and the reception unit is disposed at a position where the developer must be supplied.   The developing device according to claim 1, wherein the sound wave generation unit is disposed at a position where the developer must be supplied, and the reception unit is disposed at a position where the reception unit is not buried in the developer. The developing device according to claim 1, wherein a notch portion is provided below the cover portion.   5. The developing device according to claim 1, wherein a notch portion of the cover portion is provided with a stay prevention means for preventing the developer from staying in the cover portion.   The developing device according to claim 5, wherein the stay prevention unit includes a rotation shaft and a stirring unit attached to the rotation shaft.

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