JP2016080913A - Developer conveying device and image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To determine the amount of a developer that has passed through a conveyance path with high accuracy.SOLUTION: A developer conveying device includes: a conveyance path 51 through which a developer is conveyed; a conveyance screw 52 that is driven inside the conveyance path 51 to convey the developer; a detection sensor that detects the developer inside the conveyance path 51; and a control device 54 that determines the amount of a developer passed through the conveyance path 51 on the basis of a detection time in which the detection sensor detects the developer during the drive of the conveyance screw 52. Determining the amount of a developer actually conveyed through the inside of the conveyance path 51 enables determination of the amount of the developer with high accuracy.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a developer transport device that can determine the transport amount of a developer with high accuracy, and an image forming apparatus including the developer transport device.

  In an image forming apparatus such as a printer, a copying machine, or a facsimile machine that forms an image on a sheet using a developer, it is necessary to replenish the developer at an appropriate time in order to continue use.

  For this reason, conventionally, the time when the developer runs out is predicted, the user is notified of the time when the developer runs out, and data relating to the time when the developer runs out is sent to the host computer to manage the supply of the developer. I was doing.

  Specifically, the average data of the driving time of the replenishment motor that drives the developer supply means until the developer filled in the replenishment container runs out is obtained, and the next replenishment container in the next replenishment container is determined based on this average data. The remaining amount of developer was calculated. Based on the remaining amount of developer, an operation panel of the image forming apparatus is urged to supply the developer, and data on the remaining amount of developer is transmitted to the host computer (see Patent Document 1).

Japanese Patent Laid-Open No. 8-211792

  However, in the conventional image forming apparatus, the amount of developer used is calculated based on the driving time of the replenishment motor. For this reason, when the developer conveyance state driven by the developer supply unit driven by the replenishment motor is unstable, the replenishment motor drive time may not always accurately indicate the developer consumption. there were. For this reason, there are cases where the developer remaining amount cannot be accurately grasped.

  Furthermore, the amount of developer used may not be calculated accurately due to performance of the replenishment motor, variations in input voltage value to the replenishment motor, changes in environmental conditions, and the like.

  An automatic delivery system that predicts the amount of developer used recently and automatically issues a delivery request to a delivery center via a communication line when the developer in the supply container reaches a set remaining amount. Is being developed. Under such circumstances, when the automatic delivery system is operated in a situation where the calculation accuracy is unstable, there is a large variation in the assumed remaining amount, and there is a possibility that delivery will be delayed after the delivery timing desired by the user. In extreme cases, the developer may be delivered after it has been emptied.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a developer transport device that can determine the transport amount of a developer with high accuracy and an image forming apparatus including the developer transport device.

  The developer transport device of the present invention includes a transport path for transporting the developer, a transport unit that is driven in the transport path to transport the developer, and a developer detection unit that detects the developer in the transport path. And control means for determining the amount of developer that has passed through the conveyance path based on a detection time during which the developer detection means detects the developer during driving of the conveyance means.

  The image forming apparatus of the present invention performs development with the developer supply container, the developer transport device that transports the developer supplied from the supply container, and the developer supplied from the developer transport device. A developing device; a remaining amount calculating means for calculating the remaining amount of the developer in the replenishing container; and a remaining amount displaying means for displaying a calculation result of the remaining amount calculating means on a display panel. The means is characterized in that the remaining amount is calculated based on the developer amount of the developer obtained by the control means of the developer conveying device.

  The developer conveying device of the present invention integrates the detection time during which the conveying means is being driven and the developer detecting means detects the developer, and the control means is the amount of developer that has passed through the conveying path based on the detected time. Ask for. That is, since the developer amount actually transported in the transport path is obtained, the developer amount can be obtained with high accuracy.

  In the image forming apparatus of the present invention, the developer conveying device can determine the developer amount with high accuracy. For this reason, the remaining amount calculating means can obtain the remaining amount of the developer in the replenishing container with high accuracy by subtracting the developer amount from the filling amount of the developer initially filled in the replenishing container. . Further, the remaining amount can be displayed on the display panel to notify the user.

1 is a front view illustrating a schematic configuration of an image forming apparatus. It is a front view which shows the structure of a developing agent conveyance apparatus, a developing device, and a supply container. FIG. 3 is an enlarged front view illustrating a configuration of a developer conveying device. It is a figure which shows the output signal of a detection sensor. 6 is a flowchart illustrating a developer replenishing operation of the developer transport device. It is a figure which shows a mode that the specified amount of developer is filled into the conveyance path and the developing device. (A) is a figure which shows a mode that the developer in a conveyance path decreases, (B) is a figure which shows a mode that the developer in a conveyance path has run out, (C) is a new supply container. It is a figure which shows a mode that it replaced | exchanged.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  An embodiment of the present invention will be described with reference to FIGS.

[Image forming apparatus]
A schematic configuration of the image forming apparatus 1 will be described with reference to FIG.

  The image forming apparatus 1 includes a sheet feeding / conveying unit 10, an image forming unit 20, a sheet discharging unit 30, and an image reading unit 40 in order from the bottom.

  Among these, the sheet feeding / conveying unit 10 is provided with a sheet feeding cassette 11, a sheet feeding roller 12, a separation roller 13, a feeding path 14, and a registration roller pair 15.

  A plurality of sheets P to be used for image formation are set in a stacked state in the paper feed cassette 11. The sheet P in the paper feed cassette 11 is fed by the paper feed roller 12 and separated by one by the separation roller 13. The separated sheet P passes through the feeding path 14 and is brought into contact with the nip portion of the stopped registration roller pair 15 to correct skewing. Then, the image is formed by the rotation of the registration roller pair 15. Supplied to the unit 20.

  The image forming unit 20 is provided with a photosensitive drum 21 and a plurality of process devices. The process equipment includes a charging roller 22, an exposure unit 23, a developing device 24, a transfer roller 25, and a cleaning device 26 that are arranged in almost the order along the rotation direction of the photosensitive drum 21 (counterclockwise in FIG. 1). It is arranged. Further, a fixing device 27 is disposed above the photosensitive drum 21.

  The photosensitive drum 21 is driven to rotate, and the drum surface is charged to a predetermined polarity and potential by the charging roller 22. The charged drum surface is scanned and exposed by laser light controlled by the exposure unit 23 based on image information transmitted from an image reading unit 40 (described later) or an external computer (not shown). The surface of the drum is subjected to this scanning exposure to remove the charge at the exposed portion, thereby forming an electrostatic latent image. The electrostatic latent image is developed as a developer image with a developer attached by the developing device 24. As the developer, for example, a one-component toner is used. The developer image is conveyed to the transfer nip portion between the photosensitive drum 21 and the transfer roller 25 by the rotation of the photosensitive drum 21, and transferred to the sheet P supplied from the registration roller pair 15 described above. Thereafter, the developer remaining on the surface of the photosensitive drum 21 without being transferred to the sheet P is removed by the cleaning device 26 and used for the next image formation. On the other hand, the sheet P on which the developer has been transferred is conveyed to the fixing device 27, heated and pressurized to fix the developer image on the surface, and then conveyed to the sheet discharge unit 30.

  A discharge roller 31, a discharge tray 32, a reverse roller 33, a switching member 34, and a re-conveying path 35 are disposed in the sheet discharge unit 30. The sheet P conveyed from the fixing device 27 is discharged onto the discharge tray 32 by the discharge roller 31.

  Thus, image formation on one side of the sheet P is completed.

  In addition, when forming an image on both surfaces (front surface and back surface) of the sheet P, it is as follows. The sheet P on which the developer image is fixed on one side is conveyed to the reverse roller 33 without being discharged by the discharge roller 31. When the trailing edge of the sheet P passes through the switching member 34, the reverse roller 33 is stopped, the switching member 34 is switched, and the reverse roller 33 is further reversed. As a result, the sheet P is turned upside down and guided to the re-conveying path 35. The sheet P changes its direction upward at the lower end of the re-conveying path 35 and is conveyed to the registration roller pair 15. After that, a developer image is formed on the back surface as in the case of the front surface, fixed, and then discharged onto the discharge tray 32 by the discharge roller 31.

  Thus, image formation on both sides of the sheet P is completed.

  A platen glass 41, a document pressing plate 42, a scanning unit 43, and an operation panel (display panel) 44 are disposed in the image reading unit 40.

  The document D to be scanned is placed on the platen glass 41 with the image surface facing downward, and is brought into close contact with the platen glass 41 by the document pressing plate 42. The scanning unit 43 is formed long in the main scanning direction (a direction orthogonal to the sub-scanning direction (arrow K direction)), and is disposed on the back side of the platen glass 41. The scanning unit 43 reads the image information on the image surface of the document D while moving in the sub-scanning direction. The read image information is sent to the exposure unit 23 described above. Based on this image information, the exposure unit 23 performs on / off control of the laser beam, and exposes the drum surface of the charged photosensitive drum 21 to form an electrostatic latent image.

  On the operation panel (display panel) 44, for example, items such as sheet size, sheet orientation, number of images formed, single-sided / double-sided, and the like are displayed, and the user selects and inputs necessary items. . Note that the remaining amount of developer in the supply container 55, which will be described later, is also displayed on the operation panel 44.

  As shown in FIG. 1, a developer transport device 50, a supply container 55, and a control device (control means) 54 are disposed in the vicinity of the developing device 24. The control device 54 controls the operation of the entire image forming apparatus 1 including a developer conveying device 50 described later.

[Developer transport device]
The developer transport device 50 will be described with reference to FIGS.

  Here, FIG. 2 is a front view showing the configuration of the developer conveying device 50, the developing device 24, and the supply container 55. FIG. FIG. 3 is an enlarged front view showing the configuration of the developer transport device 50.

  2 and 3, the developer transport device 50 includes a transport path 51, a transport screw 52 as a transport unit, a detection sensor S1 as a developer detection unit, and a control device 54 as a control unit. Yes.

  Among these, the conveyance path 51 is formed in a substantially cylindrical shape with the central axis C as a reference, and is disposed in a posture in which the central axis C is substantially horizontal. In the transport path 51, a developer receiving port 51a is formed on the upper side (hereinafter simply referred to as the upstream side) along the developer transport direction (the direction of arrow A2 in FIGS. 2 and 3). The transport path 51 has a developer discharge port 51b formed on the downstream side (hereinafter simply referred to as the downstream side) along the developer transport direction. Developer is supplied to the developer receiving port 51a in the direction of arrow A from a supply container 55 described later. On the other hand, the developer discharge port 51b drops the developer from the conveyance path 51 in the arrow A3 direction and supplies the developer to the developing device 24.

  The conveying screw 52 has a shaft portion 52a, a blade portion 52b, and a wiping portion 52c. Of these, the shaft portion 52 a extends along the central axis C and is rotatably supported by the transport path 51. The blade portion 52b is provided in a spiral manner on the outer peripheral surface of the shaft portion 52a. The wiping portion 52c protrudes in a plate shape from a part of the outer peripheral surface of the shaft portion 52a. The wiping portion 52c has an upstream portion arranged along the generatrix of the shaft portion 52a, and a downstream portion curved in a substantially arc shape of ¼ of the circumference.

  The conveying screw 52 is driven and rotated at a cycle (time required for one rotation) by a screw motor M1 whose rotation is controlled by a control device 54. By one clockwise (clockwise) rotation of the screw motor M1, the blade portion 52b conveys the developer corresponding to one pitch, and the wiping portion 52c makes one rotation. As a result, the developer supplied in the direction of arrow A1 from the replenishing container 55, which will be described later, via the developer receiving port 51a is conveyed in the direction of arrow A2 along the central axis C, and from the developer discharge port 51b in the direction of arrow A3. To be discharged.

  As shown in FIG. 3, the detection sensor S <b> 1 is disposed on the downstream side of the developer receiving port 51 a in the conveyance path 51 and on the upper side of the central axis C.

  FIG. 4 is a diagram illustrating an output signal of the detection sensor S1. More specifically, an output signal when the height of the developer in the conveyance path is equal to or higher than a first height H1 (see a two-dot chain line in FIG. 3) described later is shown.

  The detection sensor S1 is a sensor that detects the presence or absence of the developer, and outputs “detection ON” (1) when the developer is detected, and outputs “detection OFF” (0) when the developer is not detected.

  This detection sensor S1 can detect the first height (first specified amount) H1 of the developer in the conveyance path 51 shown in FIG. 3 and the cycle of the conveyance screw 52. Here, the height H1 is slightly lower than the highest position of the blade portions 52b of the conveying screw 52. Note that the height corresponding to the lowest position of the blade portion 52b and the wiping portion 52c of the conveying screw 52 below the first height H1 is a second height (second prescribed amount) H2. And The developer in the transport path 51 is transported by the transport screw 52 if it is equal to or higher than the second height H2, but is not transported by the transport screw 52 if it becomes less than the second height H2.

  When the conveying screw 52 is stopped, the detection sensor S1 outputs “detection ON” when the developer is not less than the first height H1 (not less than the specified amount), and the developer is less than the height H1. “Detection OFF” is output when it is less than the specified amount. The output (1) from time (0) to approximately time (13) and from approximately time (23) to approximately time (30) in FIG. 4 corresponds to the stop state of the conveying screw 52. .

  In addition, when the conveying screw 52 is driven to rotate, the detection sensor S1 is “detection OFF” (time t0 in FIG. 4) and “detection ON” when the developer is not less than the first height H1. ”(Time t1 in FIG. 4) is repeated. That is, “detection ON” and “detection OFF” are output during one rotation of the conveying screw 52, and from “detection ON” to the next “detection ON”, or from “detection OFF” to the next “detection OFF”. One cycle is repeated.

  The detection sensor S1 outputs “detection OFF” and “detection ON” for each rotation of the conveyance screw 52 when the developer is not less than the first height H1 and the conveyance screw 52 is rotated. To do. That is, at the time of wiping by the wiping portion 52c for each rotation of the conveying screw 52, the developer in the vicinity of the detection sensor is temporarily not wiped, so that “detection OFF” is instantaneously set. However, since there is a sufficient amount of developer, the wiped portion is immediately replenished and thereafter “detection ON” is set. In the period from about time (13) to about time (23) in FIG. 4, this “detection OFF” and “detection ON” are repeated.

  The above is the case where the developer is higher than the height H1. On the other hand, when the developer is less than the height H1 and greater than or equal to the height H2, the developer is transported by the transport screw 52, but the output of the detection sensor S1 is basically “detection OFF”. Become.

  When the developer becomes less than the height H2, the developer is not transported by the blade portion 52b of the transport screw 52 and is not lifted by the wiping portion 52c. For this reason, even if the conveyance screw 52 is rotating, the detection sensor S1 is “detection OFF”.

  As will be described later, since the developer in the transport path 51 becomes less than the height H1, the developer is immediately replenished from the replenishing container 55, so that most of the time period during which the user uses the image forming apparatus 1 is used. This is the state. The developer falls below the height H1 when the developer in the supply container 55 runs out, that is, when the supply container 55 needs to be replaced.

  As shown in FIG. 3, the control device 54 includes an integration unit 54 a, a calculation unit 54 b, a reference unit 54 c, a remaining amount calculation unit 54 d, and a remaining amount display unit 54 e. The control device 54 stores a table 54f.

  Among these, the integration means 54a integrates the detection time t during which the conveyance screw 52 is rotating (while the conveyance means is being driven) and the detection sensor (developer detection means) S1 detects the developer. This detection time t corresponds to the period in FIG. 4, and the sum of “detection OFF” (time t0 in the figure) and “detection ON” (time t1) is taken as one unit. Then, the integration means 54a calculates the detection time T by integrating the detection time t (1 unit).

The calculating means 54b calculates the developer amount Q transported by the developer transport device 50 from the developer transport amount G per unit time by the transport screw 52 and the detection time T described above.
Q = G × T
Is calculated as follows.

  Note that the developer transport amount G per unit time is obtained in advance through experiments or the like. The detection time T can be calculated from the detection time t obtained based on the detection by the detection sensor S1. Further, the developer transport amount G per unit time can be easily replaced with the developer amount transported per cycle by multiplying this by the detection time t.

  The control device 54 stores a table 54f in which the detection time T and the developer amount Q are associated with each other. The reference means 54c refers to the table 54f and obtains the developer amount Q from the actually calculated detection time T.

  Note that the table 54f is obtained in advance by experiments or the like.

  The control device 54 can determine the developer amount Q regardless of which of the calculation means 54b and the reference means 54c described above, and therefore may have either one.

  The remaining amount calculating unit 54d subtracts the developer amount Q from the developer amount of the developer initially filled in the supply container 55, and calculates the remaining amount of developer in the supply container 55 (in the supply container). Is to be calculated.

  The remaining amount display unit 54e displays the remaining amount (calculation result) calculated by the above-described remaining amount calculating unit 54d on the operation panel 44.

  The developer discharged from the developer conveying device 50 described above is supplied to the developing device 24 shown in FIG.

  The developing device 24 includes a developer receiving portion 24a, a developer stirring portion 24b, a developing roller 24c, and a developing sensor S2.

  The developer receiver 24a receives the developer dropped from the developer discharge port 51b of the transport path 51 of the developer transport device 50 and supplies the developer to the developer agitator 24b. In the developer agitating unit 24b, the developer is agitated, conveyed uniformly along the longitudinal direction of the photosensitive drum 21, and applied to the surface of the developing roller 24c. The developing roller 24c develops the electrostatic latent image by attaching the applied developer to the electrostatic latent image formed on the photosensitive drum 21 described above.

  The development sensor S2 detects whether or not the developer in the developer stirring unit 24b has accumulated up to a predetermined height (third height H3). Since the developer in the developer agitating unit 24b is gradually consumed as the number of images formed by the image forming apparatus increases, the height of the developer in the developer agitating unit 24b gradually decreases. Go. The development sensor S2 detects whether or not the height has reached the third height H3 and outputs the detected height to the control device 54.

  A replenishing container 55 is disposed above the developer conveying device 50. The supply container 55 is formed in a cylindrical shape and is filled with a developer for supply. The supply container 55 is rotatably supported above the transport path 51 and is driven to rotate by a supply container motor M2. The replenishing container 55 has a discharge port (not shown) formed in a part thereof, and the developer is transported to the transport path 51 by aligning the discharge port with the developer receiving port 51a of the transport path 51 by rotational driving. Can be replenished. The developer supply operation by the supply container 55 is controlled by the control device 54.

  FIG. 5 is a flowchart for explaining the developer replenishing operation of the developer conveying device 50.

  The developer replenishing operation is performed in parallel with the image formation on the sheet P.

  As shown in FIG. 5, when performing the developer supply operation, the control device 54 first checks whether or not the development sensor S2 detects the developer (S101). When the development sensor S2 detects the developer (YES in S101), the control device 54 ends the operation. On the other hand, when the developing sensor S2 does not detect the developer (NO in S101), the control device 54 replenishes the developer by driving the screw motor M1 (S102). The control device 54 continues this supply operation until the developing sensor S2 detects the developer (NO in S103). When the developing sensor S2 detects the developer (YES in S103), the control device 54 stops driving the screw motor M1 and stops the supply of the developer (S104).

  Subsequently, the control device 54 checks whether or not the detection sensor S1 detects the developer (S105). When the detection sensor S1 detects the developer (S105), the control device 54 ends the operation. On the other hand, when the detection sensor S1 does not detect the developer (NO in S105), the control device 54 drives the supply container motor M2 to supply the developer (S106). The controller 54 continues this replenishment operation until the detection sensor S1 detects the developer (NO in S107). When the detection sensor S1 detects the developer (YES in S107), the controller 54 stops driving the supply container motor M2, stops supplying the developer (S108), and ends the operation.

  The controller 54 can supply the developer from the transport path 51 to the developing device 24 and can supply the developer from the supply container 55 to the transport path 51 by repeating the above operation.

  FIG. 6 is a diagram showing the state of the developer in the transport path 51 and the developing device 24 when the supply of the developer is controlled according to the flowchart shown in FIG.

  When the developing sensor S2 no longer detects the developer by the operation according to the flowchart shown in FIG. 5, the conveying screw 52 is driven by the screw motor M1, and the developer is supplied from the conveying path 51 to the developing device 24. When the detection sensor S1 no longer detects the developer, the supply container 55 is rotated by the supply container motor M2, and the developer is supplied from the supply container 55 to the transport path 51.

  Therefore, as shown in FIG. 6, when the developer remains in the supply container 55, the transport path 51 has a first height H1 (first specified amount) corresponding to the detection position of the detection sensor S1. ) Until the developer is stored. On the other hand, the developer is stored in the developing device 24 up to the third height H3 (second specified amount) corresponding to the detection position of the development sensor S2.

  As described above, the developer in the transport path 51 (in the transport path) substantially maintains the first height H1 when the developer remains in the supply container 55. For this reason, the developer conveyance amount G per one rotation (one cycle) of the conveyance screw 52 is kept substantially constant. For this reason, when the developer remains in the replenishing container 55, the developer amount Q so far can be obtained with relatively high accuracy.

  Next, the operation when the developer in the supply container 55 runs out will be described.

  FIGS. 7A to 7C are views showing a state in which the developer in the supply container 55 runs out and is replaced with a new supply container 55. Specifically, FIG. 7A is a diagram showing how the developer in the transport path 51 decreases. FIG. 7B is a diagram illustrating a state in which the developer in the transport path 51 has run out. FIG. 7C is a diagram illustrating a state in which the developer is supplied from the supply container 55 to the conveyance path 51 until it is replaced with a new supply container 55 and the detection sensor S1 detects the developer.

  When the developer is supplied from the supply container 55 to the transport path 51 and the developing device 24 and image formation is performed, the developing sensor S2 eventually detects the developer and the detection sensor S1 cannot detect the developer. Become. That is, as shown in FIG. 7A, the developer in the developer stirring unit 24b of the developing device 24 is not less than the third height H3, and the developer in the transport path 51 is the first height. It is in a state of being less than H1.

  As shown in FIG. 7A, even when the developer in the replenishing container 55 runs out and the detection sensor S1 cannot detect the developer (the developer is less than the height H1), the image forming apparatus 1 is executed, and the developer in the developing device 24 is consumed. Then, the developing sensor S2 enters a state where the developer is not detected (the developer is less than the height H3). Even in such a state, the screw motor M1 is driven as described above, and the developer is supplied from the conveyance path 51 by the conveyance screw 52. At this time, since the developer cannot be supplied from the replenishing container 55 to the transport path 51, the developer in the transport path 51 decreases each time the screw motor M1 is driven.

  In this state, when the image forming process is continuously performed, the supply of the developer by the screw motor M1 is continued to be executed, and eventually there is no developer in the conveyance path 51 (the developer is less than the height H2), that is, the screw motor. M1 enters an idle state where no developer is supplied. This is the state shown in FIG. In this state, since the developer is not supplied to the developing device 24, the development sensor S2 does not detect the developer (the developer is less than H3).

  When the development sensor S2 does not detect the developer and the development sensor S2 does not detect the developer even if a certain time has elapsed, the remaining amount display means 54e of the control device 54 is displayed on the operation panel 44 (see FIG. 1). Displays no developer. Then, as described above, the operation panel 44 prompts the replacement of the supply container 55, and the image forming job is not accepted, that is, the image forming apparatus 1 is not in an image forming state. This is the idle period during which the screw motor M1 is not supplying the developer. In this embodiment, since the detection sensor S1 outputs “detection OFF” during this period, the detection time T is not counted.

  Further, as shown in FIG. 7C, when the replacement of the replenishing container 55 that has run out of the developer is completed, the developer is replenished in the transport path 51 and the developing device 24. Then, the detection sensor S1 and the development sensor S2 detect the developer, that is, the developer replenishment operation is completed.

  The developer conveying device 50 described above can determine the developer amount Q with high accuracy.

  That is, most of the entire period from the start of using one replenishing container 55 until the developer runs out, holds the height H1 of the developer in the transport path 51 (the detection sensor S1 is “detection ON”). Therefore, the developer conveyance amount per unit time (conveyance amount per cycle) G by the conveyance screw 52 is substantially constant, while the controller 54 detects the detection sensor as described above. The accumulating unit 54a can calculate the detection time T with high accuracy based on the output of S1 The control device 54 performs calculation by the calculation unit 54b based on the transport amount G and the detection time T or references By referring to the table 54f by the means 54c, the developer amount Q can be obtained with high accuracy.

  When the developer in the transport path 51 is at a height H1 or less and the developer is not supplied from the supply container 55, the detection sensor S1 continuously outputs “detection OFF”. The developer transport time in this state is not included in the detection time T.

  In addition, the ratio of the time of “detection OFF” (time t0) and “detection ON” (time t1) in one cycle in FIG. 4 is the property of the developer (for example, the viscosity of the developer itself or the humidity of the use environment). The viscosity of the developer based on the For example, when the viscosity of the developer is high, it takes a longer time for the developer to backfill the space wiped by the wiping unit 52c than when the developer is low, so that “detection OFF” (time t0) becomes longer. Accordingly, “detection ON” (time t1) is shortened. That is, the ratio of “detection OFF” (time t0) in one cycle increases, and the ratio of “detection ON” (time t1) decreases accordingly.

  By the way, when the viscosity of the developer is high, the transport amount G of the developer per unit time by the transport screw 52 decreases.

  Therefore, the developer amount Q can be obtained with higher accuracy by correcting the developer transport amount G per unit time based on the ratio between the times t0 and t1 in one cycle. .

  G: developer transport amount per unit time, H1: first height (specified amount), Q: developer amount that has passed through the transport path, P: sheet, S1: detection sensor (developer detection means), T ... detection time, t ... detection time (cycle), t0 ... "detection OFF" time, t1 ... "detection ON" time, 1 ... image forming apparatus, 24 ... developing apparatus, 50 ... developer conveying apparatus, 51 ... Conveying path, 52 ... Conveying screw (conveying means), 52c ... Wiping unit, 54 ... Control device (control means), 54a ... Integrating means, 54b ... Calculating means, 54c ... Reference means, 54d ... Remaining amount detecting means, 54e ... remaining amount display means, 54f ... table, 55 ... supply container.

Claims (7)

A transport path through which the developer is transported;
Conveying means driven in the conveying path to convey the developer;
Developer detecting means for detecting the developer in the transport path;
Control means for determining the amount of developer that has passed through the conveyance path based on a detection time during which the developer detection means detects the developer during driving of the conveyance means;
A developer carrying device. The control unit obtains the developer amount from the transport amount of the developer per unit time by the transport unit and the detection time;
The developer conveying device according to claim 1, wherein: The control means obtains the developer amount based on the table in which the detection time and the developer amount are associated with each other, and the table.
The developer conveying device according to claim 1, wherein: The developer detection means is a detection sensor that detects the presence or absence of a developer,
The conveying means is a conveying screw having a wiping portion for temporarily wiping the developer in the vicinity of the detection sensor every rotation.
The detection sensor is “detection OFF” when the developer in the transport path becomes less than a specified amount, and when the developer is more than a specified amount and when the developer is wiped by the wiping portion during one rotation of the transport screw. Output,
The developer conveying device according to any one of claims 1 to 3, wherein The control means sets the sum of the “detection OFF” time and the “detection ON” time per rotation of the screw as one unit, and calculates the detection time by adding the one unit.
The developer conveying device according to claim 4. The control unit corrects the amount of developer transported per unit time by the transport unit in accordance with a ratio of the “detection OFF” time and the “detection ON” time to the unit.
The developer conveying device according to claim 5, wherein A developer supply container;
The developer conveying device according to any one of claims 1 to 6, wherein the developer supplied from the replenishing container is conveyed.
A developing device for developing with the developer supplied from the developer transport device;
A remaining amount calculating means for calculating the remaining amount of the developer in the supply container;
Remaining amount display means for displaying a calculation result of the remaining amount calculation means on a display panel,
The remaining amount calculating means calculates the remaining amount based on the developer amount of the developer obtained by the control means of the developer conveying device;
An image forming apparatus.

Images