JP5114269B2 - Toner supply device and image forming apparatus - Google Patents

Description

  The present invention relates to a toner supply device used in an image forming apparatus that forms an image on a recording medium such as an electrophotographic copying machine or a laser printer.

  2. Description of the Related Art Conventionally, some image forming apparatuses as described above are provided with a toner supply device that can be attached to and detached from the main body of the developing unit of the image forming apparatus. A toner supply device employed in an image forming apparatus capable of color printing has a toner hopper for storing toner of each color (for example, black, yellow, cyan, and magenta). And a stirring paddle for stirring the toner. Each toner hopper is replenished with toner from the toner cartridge, and the stirring paddle is rotated to transport the toner in the direction of the transport spiral while being stirred, and the toner is collected from the toner supply port by the rotation of the transport spiral. The toner is supplied from the toner supply port to the developing unit.

  Recently, there is a demand for downsizing and cost reduction of image forming apparatuses. Therefore, a method is adopted in which a plurality of agitation paddles are operated by a single drive source to reduce the drive sources, thereby reducing the size and cost of the toner supply device. However, when only one drive source is used, for example, even when an image is formed using only black toner (monochrome printing), the stirring paddles of all the color toners rotate at the same time. It will be stirred as necessary. Such excessive stirring of the toner causes toner deterioration and causes image deterioration. In addition, since a useless load is applied to the drive source, power consumption is high.

Patent Document 1 describes an image forming apparatus in which driving sources are reduced by driving replenishing screws (conveying spirals) of two developer replenishing devices with one driving source.
JP 2006-201314 A

  However, in the case of the method described in Patent Document 1, in the two developer replenishing devices in which the replenishing screw is driven by the same drive source, the replenishing screw cannot be operated simultaneously. In other words, toner cannot be efficiently supplied from the developer supply device to the development device. In addition, an electromagnetic clutch is used to switch the drive of the replenishing screw, and the electromagnetic clutch generates heat when it is energized. Therefore, it is considered that the temperature around the electromagnetic clutch rises and causes toner deterioration. Furthermore, the configuration of the stirring member (stirring paddle) described in Patent Document 1 is not described at all, and as described above, the stirring members of the respective colors are collectively used by one driving source. In the case of a general configuration for driving, the toner is unnecessarily agitated, resulting in toner deterioration.

  The present invention has been made to solve the above-described problem. In a toner supply device that rotates a plurality of stirring paddles with a single drive source, the rotation / non-rotation of the stirring paddles is controlled according to the toner used. It is an object of the present invention to propose a toner supply device that efficiently replenishes toner to a developing device while preventing unnecessary stirring of toner.

According to a first aspect of the present invention, there is provided a toner supply device that is arranged in parallel and stores a plurality of storage units that store toners of different colors, and is disposed in each storage unit and stirs or conveys the stored toner. a stirring means for the driving means for applying a driving force by the drive output shaft for each stirring means, are respectively engaged in positions corresponding to the respective stirring means of the drive output shaft, wherein the said drive output shaft Drive transmission means for transmitting the driving force of the drive means to a drive input shaft provided on the stirring means side, and at least one drive transmission means for arranging the drive output shaft on the drive means side are arranged. the primary side, the disposed on the primary side and coaxially, and another of said drive transmitting means is arranged the secondary side, coupling and decoupling can be the drive output in a state in which the drive transmission means is engaged Connect shaft A connecting means that includes a control unit that controls to bind or separate the secondary side to the primary side of the drive output shaft in accordance with the setting determined in advance makes to the coupling means, wherein the drive output shaft The secondary side that is installed at one end of the primary side and the secondary side that is installed at one end of the secondary side and is detachable in the axial direction of the drive output shaft between the primary side connection member A primary side and a secondary side of the drive output shaft are coupled or disengaged by fitting and detaching the primary side connection member and the secondary side connection member in the axial direction. separated is characterized in Rukoto.

  According to this configuration, when image formation is performed using only the toner stored in the storage unit corresponding to the drive transmission unit disposed on the primary side of the drive output shaft, the drive output shaft is connected to the primary side and the secondary side. Since the drive force of the drive means is not transmitted to the secondary side by separating the toner from the side, the toner stored in the storage means corresponding to the drive transmission means arranged on the secondary side is not stirred. Therefore, toner that is not used for image formation is not unnecessarily stirred, and toner deterioration due to excessive stirring can be suppressed. Further, by separating the drive output shaft according to the setting, it is possible to reduce the load on the drive means and to suppress power consumption.

  The invention according to claim 2 is the toner supply device according to claim 1, wherein the drive transmission means disposed on the primary side of the drive output shaft is a predetermined high-use toner. When the toner image is formed on the image carrier using only the predetermined frequently used toner, the driving input shaft of the stirring unit disposed in the storage unit for storing the toner is used. The control means controls the connection means to separate the drive output shaft.

  According to this configuration, it is possible to prevent unnecessaryly agitated toner from being agitated and to suppress toner deterioration due to excessive agitation.

  According to a third aspect of the present invention, in the toner supply device according to the first or second aspect, the storage unit includes a black toner storage unit that stores black toner, and a primary output of the drive output shaft. The drive transmission means arranged on the side is connected to a drive input shaft of a stirring means arranged in the black toner storage means, and a toner image is formed on the image carrier using only the black toner. The control means performs control for separating the drive output shaft on the connecting means.

  According to this configuration, when image formation is performed in monochrome, only the black toner can be agitated by separating the drive output shaft into the primary side and the secondary side. Therefore, the color toner can be prevented from being unnecessarily agitated, and toner deterioration due to excessive agitation can be suppressed.

According to a fourth aspect of the present invention, there is provided the toner supply device according to any one of the first to third aspects, wherein the connecting means operates in accordance with a keep solenoid and a drive of the keep solenoid. An oscillating member, and a biasing spring that biases one of the primary side connecting member and the secondary side connecting member toward the other, the primary side connecting member and the secondary side connecting member, It is fitted by the urging force of the urging spring, and one of the primary side connecting member and the secondary side linking member is separated from the other against the urging force of the urging spring by the operation of the swing member. It is characterized by.

  If the keep solenoid outputs a control signal (electrical signal) only when switching on / off, it keeps the on / off state in a non-energized state thereafter. Therefore, the connecting means can be driven with less power consumption. In addition, since the keep solenoid does not need to be energized, toner deterioration does not occur due to a temperature rise due to constant heat generation.

  According to a fifth aspect of the present invention, there is provided an image forming apparatus comprising the toner supply device according to any one of the first to fourth aspects.

  According to this structure, there can exist an effect similar to the effect of the invention of Claims 1-4.

  According to the present invention, when image formation is performed using only the toner stored in the storage unit corresponding to the drive transmission unit disposed on the primary side of the drive output shaft, the drive output shaft is connected to the primary side and the secondary side. Since the drive force of the drive means is not transmitted to the secondary side by separating the toner from the side, the toner stored in the storage means corresponding to the drive transmission means arranged on the secondary side is not stirred. Therefore, toner that is not used for image formation is not unnecessarily stirred, and toner deterioration due to excessive stirring can be suppressed. Further, by separating the drive output shaft according to the setting, it is possible to reduce the load on the drive means and to suppress power consumption. Further, by using a keep solenoid for the connecting means, the connecting means can be driven with less power consumption.

  Embodiments of a toner supply device and an image forming apparatus according to the present invention will be described with reference to the drawings. The image forming apparatus according to this embodiment is an electrophotographic image forming apparatus, and can be applied to a printer, a copying machine, a facsimile, or a multifunction machine having these functions.

  FIG. 1 is a schematic cross-sectional view of an image forming apparatus according to the present embodiment. In this embodiment, the case where the present invention is applied to a tandem type image forming apparatus will be described. However, in addition to the tandem system, an image forming apparatus adopting another printing system such as an intermediate transfer belt system is used. Applicable.

  The image forming apparatus 1 includes a photosensitive member 21 that can hold an electrostatic latent image by charging, a charging device 22 that charges the photosensitive member 21, an exposure unit 27 that forms an electrostatic latent image on the photosensitive member 21, and the photosensitive member 21. A developing device 31 that supplies toner to the toner image to visualize the toner image, a transfer device 28 that transfers the toner image formed on the photosensitive member 21 to the conveyed paper 23, and a toner cartridge 26 that replenishes the developing device 31 with toner. (Toner cartridges 26K, 26Y, 26C, and 26M) are provided corresponding to each color of black, yellow, cyan, and magenta. In addition, a paper feed cassette 24 that accommodates the paper 23, a transport belt 25 that takes out the paper 23 from the paper feed cassette 24 and transports it, and a fixing device 29 that fixes the toner images of each color transferred to the paper 23 are provided. The paper 23 on which the toner image is fixed by the fixing device 29 is discharged to the paper discharge tray 40.

  FIG. 2 is a perspective view of the toner supply device 8. The toner supply device 8 includes a toner hopper 80K that stores black toner, a toner hopper 80Y that stores yellow toner, a toner hopper 80C that stores cyan toner, and a toner hopper 80M that stores magenta toner (hereinafter, collectively referred to as “toner hopper (storage unit) 80”. ”). The toner cartridges 26K, 26Y, 26C, and 26M for the respective colors shown in FIG. 1 are arranged above each toner hopper 80 (upper side in the Z direction), and toner is supplied from the toner cartridge 26 to each hopper 80.

  In each toner hopper 80, stirring paddles (stirring means) 81K, 81Y, 81C, 81M (hereinafter, collectively referred to as “stirring paddle 81”) and conveying spirals 82K, 82Y, 82C, 82M (hereinafter, generally referred to as “transporting”). Spiral 82 ") is arranged. The agitation paddle 81 agitates the stored toner and conveys it in the direction of the conveyance spiral 82. The conveyance spiral 82 conveys toner so as to be collected near the toner supply ports 84K, 84Y, 84C, and 84M (hereinafter, collectively referred to as “toner supply port 84”). Then, toner is supplied from each toner supply port 84 to the developing unit 7.

  The shaft (drive output shaft) 9 is connected to a shaft drive motor (drive means) 90 via a drive input gear 91. When the shaft drive motor 90 is driven to rotate, a rotational force is transmitted from the drive input gear 91 to rotate. . On the shaft 9, paddle drive gears 92K, 92Y, 92C, and 92M (hereinafter collectively referred to as “paddle drive gear 92”) for transmitting the rotational force of the shaft drive motor 90 to each of the agitation paddles 81 are each agitated paddle. It is installed at a position corresponding to 81. Each transport spiral 82 is rotationally driven by transport spiral drive motors 83K, 83Y, 83C, and 83M.

  FIG. 3 is a side sectional view of the toner supply device 8 when viewed from the X direction. A paddle drive gear 92M having the shaft 9 as an axis meshes with an idler gear 95, and the idler gear 95 meshes with a paddle gear 96. The idler gear 95 is rotatably supported by a shaft 95a. The paddle gear 96 is rotatably supported by a shaft (drive input shaft) 96a, and a stirring paddle 81M is fixed to the shaft 96a in the toner hopper 80M. That is, when the shaft 9 rotates, the gears of the paddle drive gear 92M, the idler gear 95, and the paddle gear 96 mesh with each other, the shaft 96a rotates, and the stirring paddle 81M rotates. With the same mechanism, the other stirring paddles 81K, 82Y and 82C also rotate. Here, the paddle drive gear 92, the idler gear 95, and the paddle gear 96 correspond to drive transmission means.

  FIG. 4 is a perspective view of the shaft 9 and the shaft connecting portion 2. The shaft connecting portion 2 is a member for connecting the primary side shaft 9a and the secondary side shaft 9b such as the keep solenoid 20, the plunger 201, the slider arm 202, the shaft 203, the concave joint 93, and the convex joint 94. .

  The shaft 9 is connected to or separated from the primary side shaft 9a and the secondary side shaft 9b by the operation of the keep solenoid 20. FIG. 4 is a view when the primary shaft 9a and the secondary shaft 9b are in a connected state. The primary shaft 9a includes a drive input gear 91, at least one paddle drive gear (paddle drive gear 92K in the present embodiment), and a concave joint (primary connection member) 93 for connecting to the secondary shaft 9b. Have. The secondary side shaft 9b includes other paddle drive gears (paddle drive gears 92Y, 92C, and 92M in the present embodiment) that are not disposed on the primary side shaft 9a, and a convex joint (secondary) for connecting to the primary side shaft 9a. Secondary side connecting member) 94.

  The concave joint 93 and the convex joint 94 can be fitted and separated, and the convex joint 94 is usually fitted into the concave joint 93 by the force of the spring 97. That is, the primary shaft 9a and the secondary shaft 9b are connected. When the shaft drive motor 90 is driven in the connected state (fitted state), the primary shaft 9a and the secondary shaft 9b rotate together, and the rotational force is transmitted from each paddle drive gear 92 to each stirring paddle 81. Then, the toner in each toner hopper 80 is agitated all at once.

  The primary shaft 9a and the secondary shaft 9b are separated by driving the keep solenoid 20 in accordance with an instruction signal output from a control unit described later. The keep solenoid 20 is driven in response to an instruction signal output from the control unit, and the plunger 201 connected to the keep solenoid 20 projects in the arrow B direction (± X direction).

  One end of the plunger 201 and one end of the slider arm (swinging member) 202 are pivotally supported, and the other end of the slider arm 202 operates in the direction of arrow B with the shaft 203 as a fulcrum. When the plunger 201 protrudes in the −X direction, the other end of the slider arm 202 faces in the + X direction, the convex joint 94 is engaged with the concave joint 93 by the force of the spring 97, and the primary shaft 9a and the secondary side are engaged. The shaft 9b is connected. Conversely, when the plunger 201 is pulled in the + X direction, the other end of the slider arm 202 faces the −X direction, and the convex joint 94 is extracted from the concave joint 93.

  FIG. 5 is a cross-sectional view of the slider arm 202, the concave joint 93, and the convex joint 94. When the keep solenoid is driven and the slider arm 202 moves to the position C indicated by the dotted line, the other end of the slider arm 202 hooks the claw 941 of the convex joint 94 to extract the convex joint 94 from the concave joint 93. At this time, the primary shaft 9a and the secondary shaft 9b are in a separated state. When the shaft drive motor 90 is driven in the separated state, the rotational force is transmitted only from the paddle drive gear 92K to the stirring paddle 81K via the primary shaft 9a, and only the black toner in the toner hopper 80K is stirred. Since the rotational force of the shaft drive motor 90 is not transmitted to the secondary shaft 9b, the other stirring paddles 81Y, 82C and 82M do not rotate.

  That is, for example, when performing color printing, the primary shaft 9a and the secondary shaft 9b are connected to rotate all the stirring paddles 81, and when performing monochrome printing, the primary shaft 9a and the secondary shaft 9b are connected. Only the stirring paddle 81K that separates and stirs the black toner is controlled to rotate. By doing this, since the color toner is not stirred when the color toner is not used, the deterioration of the toner due to excessive stirring can be suppressed. In addition, the load on the shaft drive motor 90 during monochrome printing can be reduced, and power consumption can be suppressed.

  FIG. 6 is a functional block diagram showing an electrical configuration of the image forming apparatus 1. The image forming apparatus 1 includes a control unit (control unit) 100, a storage unit 101, a document reading unit 102, an image memory 103, an image processing unit 104, a sheet feeding unit 105, a keep solenoid 20, an image forming unit 106, and an input operation unit 107. And a network I / F unit 108.

  The control unit 100 is configured by a CPU (Central Processing Unit) or the like, reads a program stored in the storage unit 101 in accordance with an input instruction signal or the like, executes a process, The multifunction device 1 is comprehensively controlled by outputting an instruction signal, transferring data, and the like. The control unit 100 includes a mode setting unit 110. A mode setting unit 110 automatically determines whether an input operation by a user at the input operation unit 107 or an image of a document read by the document reading unit 102 is a black and white document or a color document. Based on the function, whether to perform monochrome or color image formation is set.

  When the image formation is switched from color to monochrome, the control unit 100 outputs an instruction signal to the keep solenoid 20. In response to this instruction signal, the keep solenoid 20 is turned on (pull side), and the slider arm 202 is operated in a direction to extract the convex joint 94 from the concave joint 93 as shown in FIG. As a result, the primary side shaft 9a and the secondary side shaft 9b are separated, and only the stirring paddle 81K rotates in synchronization with the drive of the shaft drive motor 90, and only the black toner is stirred.

  Conversely, when switching the image formation from monochrome to color, the control unit 100 similarly outputs an instruction signal to the keep solenoid 20. In response to this instruction signal, the keep solenoid 20 is turned off (push side) in response to this signal to return the slider arm 202 to its original position. Then, the convex joint 94 is fitted into the concave joint 93 by the force of the spring 97, and the primary shaft 9a and the secondary shaft 9b are connected. In this way, the keep solenoid 20 is turned on / off in accordance with the control signal output from the control unit 100, and the coupling / separation of the shaft 9 is controlled.

  The storage unit 101 stores programs and data for realizing various functions provided in the image forming apparatus 1. The document reading unit 102 reads a document with various image sensors and converts the read image into image data.

  The image memory 103 temporarily stores image data output from the document reading unit 102 and image data transmitted from an external device via the network I / F unit 108. The image processing unit 104 performs image processing such as image correction and enlargement / reduction on the image data stored in the image memory 103. The paper feeding unit 105 feeds paper one by one from the paper feeding mechanism 10 to the image forming unit 106.

  The image forming unit 106 forms an image on paper based on the image data stored in the image memory 103. The input operation unit 107 includes a display panel and various operation buttons, and outputs an operation signal to the control unit 100 when an operation is performed by a user. The network I / F unit 108 includes a communication module such as a LAN board, and transmits / receives various data to / from an external device via a network (not shown) connected to the network I / F unit 108.

  As described above, for example, when performing color printing, the primary shaft 9a and the secondary shaft 9b are connected, so that the toner of each color can be efficiently stirred and conveyed simultaneously by one shaft drive motor 90. it can. On the other hand, when performing monochrome printing, the primary shaft 9a and the secondary shaft 9b are separated to rotate only the stirring paddle 81K that stirs the black toner, thereby preventing the color toner from being unnecessarily stirred. Toner deterioration due to excessive stirring can be suppressed. In addition, the load on the shaft drive motor 90 during monochrome printing can be reduced, and power consumption can be suppressed.

  Further, if the self-holding type keep solenoid 20 outputs a control signal (electrical signal) only when switching on / off, the self-holding type keep solenoid 20 is maintained in the on / off state in a non-energized state thereafter. Therefore, the keep solenoid 20 can be driven with less power consumption. Further, since it is not necessary to keep energizing the keep solenoid 20, toner deterioration is not caused by a temperature rise due to constant heat generation, and the temperature around the keep solenoid 20 is not raised.

  The present invention is not limited to the configuration of the above embodiment, and various modifications can be made. In the above, when the paddle drive gear 92K is disposed on the primary shaft 9a and the shaft 9 is in a separated state such as when performing monochrome image formation, only the stirring paddle 81K rotates and only the black toner is stirred, It has been described that the other color toners are not stirred. In addition to this, in addition to the paddle driving gear 92K on the primary side shaft 9a, a paddle driving gear corresponding to the frequently used toner is arranged, and the paddle driving gear corresponding to the infrequently used toner is arranged on the secondary side shaft 9b. It may be arranged. That is, among the color toners described above, for example, when the use frequency of yellow toner is significantly higher than the use frequency of cyan and magenta toner, the paddle drive gear 93Y may be arranged on the primary shaft 9a side.

1 is a front sectional view showing a schematic configuration of an image forming apparatus. FIG. 3 is a perspective view of a toner supply device. FIG. 3 is a side sectional view of the toner supply device. The perspective view of a shaft and a shaft connection part. Sectional drawing of a slider arm, a concave joint, and a convex joint. FIG. 3 is a functional block diagram showing an electrical configuration of the image forming apparatus.

Explanation of symbols

1 Image forming apparatus 8 Toner supply devices 80K, 80Y, 80C, 80M Toner hoppers 81K, 81Y, 81C, 81M Agitating paddles 82K, 82Y, 82C, 82M Conveying spirals 83K, 83Y, 83C, 83M Conveying spiral drive motors 84K, 84Y, 84C 84M Toner supply port 9 Shaft 9a Primary shaft 9b Secondary shaft 90 Shaft drive motor 91 Drive input gears 92K, 92Y, 92C, 92M Paddle drive gear 93 Concave joint 94 Convex joint 95 Idler gear 96 Paddle gear 97 Spring 20 Keep solenoid 201 Plunger 202 Slider arm

Claims (5)

A plurality of storage means arranged in parallel and storing toners of different colors;
An agitation unit disposed in each of the storage units and stirring or conveying the stored toner;
Driving means for applying a driving force to each of the stirring means by a drive output shaft;
Are respectively engaged at a position corresponding to the respective stirring means of the drive output shaft, a drive transmission means for transmitting the driving force of said driving means to drive the input shaft provided in the agitating means side from the drive output shaft,
The drive output shaft is disposed on the drive means side, the primary side on which at least one of the drive transmission means is disposed, the first side is disposed on the same axis, and the other drive transmission means is disposed on the second side. and following side, and connecting means for connecting the drive output shaft to be capable of coupling and decoupling in a state in which the drive transmission means is engaged,
Control means for controlling the coupling means to couple or separate the primary side and the secondary side of the drive output shaft according to a predetermined setting;
Equipped with a,
The drive output shaft includes a primary side connecting member installed at one end of the primary side and a primary side of the secondary side.
A secondary side connecting member that is installed at an end and is detachable in the axial direction of the drive output shaft between the primary side connecting member and
It said connecting means by Hamada' in the axial direction and the secondary-side connecting member and the primary-side connecting member, a toner supply apparatus and the primary side and the secondary side of the drive output shaft Ru coupled or separated. The drive transmission means arranged on the primary side of the drive output shaft is connected to a drive input shaft of a stirring means arranged in a storage means for storing a predetermined high-use toner.
When a toner image is formed on the image carrier using only the predetermined frequently used toner, the control unit controls the coupling unit to separate the drive output shaft. The toner supply device according to claim 1. The storage means has black toner storage means for storing black toner,
The drive transmission means arranged on the primary side of the drive output shaft is connected to the drive input shaft of the stirring means arranged in the black toner storage means,
2. The control unit performs control for separating the drive output shaft on the coupling unit when a toner image is formed on the image carrier using only the black toner. Or the toner supply device according to 2; The connecting means includes a keep solenoid, a swinging member that operates in accordance with the drive of the keep solenoid, and a biasing spring that biases one of the primary side connecting member and the secondary side connecting member toward the other. , has a,
Said primary-side connecting member and the secondary-side connection member is fitted by the biasing force of the biasing spring, one of which with the of the primary-side connecting member and the secondary-side connecting member by the operation of the swing member The toner supply device according to claim 1, wherein the toner supply device is separated from the other against the urging force of the urging spring .   An image forming apparatus comprising the toner supply device according to claim 1.

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