JP7200564B2 - Toner conveying device and image forming device - Google Patents

Description

The present invention relates to a toner conveying device and an image forming apparatus.

Japanese Unexamined Patent Application Publication No. 2002-100000 discloses a developer conveying device having a toner loosening means by driving a chain-breaking member arranged in a vertical conveying path along which toner is conveyed.

Further, Japanese Patent Application Laid-Open No. 2002-200002 discloses a toner conveying device that conveys toner by vertically moving a conveying path itself by driving a drive mechanism.

Further, Japanese Patent Application Laid-Open No. 2002-200001 discloses a curved toner path forming member having a curved path shape that prevents narrowing of a gap between a transport path and a transport coil in a curved transport path.

JP 2014-081544 A JP 2017-049279 A JP 2013-156511 A

The present invention suppresses clogging of toner in a configuration in which toner in a toner storage unit is supplied to a developing device by falling in a vertical conveying path, compared to a simple pipe with a closed vertical conveying path. It is an object of the present invention to obtain a toner transport device which is capable of

A toner conveying device according to a first aspect includes a cylindrical vertical conveying path that guides toner from a toner container downward in the vertical direction and is connected to a developing device at the lower vertically direction, and the vertical conveying path. an inflow port that allows air to flow into the vertical conveying path from the cylinder wall.

A toner conveying device according to a second aspect is the toner conveying device according to the first aspect, wherein the vertical conveying path has an opening area of the toner outlet on the lower end side in the vertical direction that is larger than that of the toner inlet on the upper end side in the vertical direction. Larger than the opening area.

A toner conveying device according to a third aspect is the toner conveying device according to the first aspect or the second aspect, which extends above the vertical conveying path in a direction intersecting the vertical conveying path, and includes the toner containing portion. and the vertical transport path for transporting the toner; and a transport member provided inside the transport path for transporting the toner along the transport path.

A toner conveying device according to a fourth aspect is the toner conveying device according to any one of the first aspect to the third aspect, wherein the inlet is tubular, and the vertical conveying path is cylindrical. It is provided along the normal direction of the wall.

A toner conveying device according to a fifth aspect is the toner conveying device according to any one of the first aspect to the third aspect, wherein the inflow port is tubular, and the vertical conveying path is cylindrical. It is provided along the inner wall of the wall.

A toner conveying device according to a sixth aspect is the toner conveying device according to any one of the first aspect to the fifth aspect, wherein the inflow port is tubular, and the vertical conveying path is cylindrical. It extends diagonally upwards from the wall.

A toner conveying device according to a seventh aspect is the toner conveying device according to any one of the first to sixth aspects, wherein a plurality of the inlets are provided in the cylindrical wall of the vertical conveying path. It is

A toner conveying device according to an eighth aspect is the toner conveying device according to the seventh aspect, wherein the plurality of inlets are arranged with their positions shifted in the vertical direction on the cylindrical wall of the vertical conveying path.

A toner conveying device according to a ninth aspect is the toner conveying device according to any one of the first aspect to the eighth aspect, wherein a coil-shaped toner for breaking up toner is provided inside the vertical conveying path. of collapsing members are provided.

A toner conveying device according to a tenth aspect is the toner conveying device according to the ninth aspect, wherein the breaking member moves vertically.

A toner conveying device according to an eleventh aspect is the toner conveying device according to any one of the first aspect to the tenth aspect, wherein the toner conveying device is connected to the inflow port and allows air to flow into the vertical conveying path. has an introduction means for introducing into

An image forming apparatus according to a twelfth aspect comprises a toner conveying device according to any one of the first to eleventh aspects, and a developing device connected to the vertical conveying path of the toner conveying device. an image carrier on which a toner image is formed by the toner of the developing device; and a transfer device for transferring the toner image on the image carrier to a recording medium.

An image forming apparatus according to a thirteenth aspect is the image forming apparatus according to the twelfth aspect, wherein the toner conveying device is the one according to any one of claims 1 to 10, and A circulation means is connected to the developing device and the inflow port, and circulates the air in the developing device from the inflow port to the inside of the vertical transport path by the internal pressure of the developing device.

According to the toner conveying device according to the first aspect, in the structure in which the toner in the toner containing portion drops in the vertical conveying path and is supplied to the developing device, the vertical conveying path is closed and the toner conveying apparatus is a mere tube. In comparison, toner clogging is suppressed.

According to the toner conveying device according to the second aspect, compared to a configuration in which the inner diameter of the vertical conveying path is constant along the vertical direction, toner is less likely to clog the lower end portion of the vertical conveying path.

According to the toner conveying device according to the third aspect, clogging of toner is suppressed in the configuration in which the toner density increases as the toner is conveyed to the vertical conveying path.

According to the toner conveying device according to the fourth aspect, the aggregated toner is easily loosened compared to the configuration in which air is introduced downward from the upper portion of the vertical conveying path.

According to the toner conveying device according to the fifth aspect, the aggregated toner is easily loosened compared to the configuration in which air is introduced downward from the upper portion of the vertical conveying path.

According to the toner conveying device according to the sixth aspect, the aggregated toner is easily loosened compared to the configuration in which the vertical conveying path extends obliquely downward from the cylinder wall.

According to the toner conveying device according to the seventh aspect, aggregated toner is easily loosened compared to a configuration in which only one air inlet is provided in the vertical conveying path.

According to the toner conveying device according to the eighth aspect, aggregated toner is easily disassembled compared to a configuration in which a plurality of inlets are provided at the same position in the vertical direction of the vertical conveying path.

According to the toner conveying device according to the ninth aspect, the aggregated toner is easily loosened compared to the case where the vertical conveying path is hollow.

According to the toner conveying device according to the tenth aspect, the aggregated toner is easily loosened compared to the structure in which the breaking member rotates.

According to the toner conveying device according to the eleventh aspect, the introducing means can introduce air into the vertical conveying path.

According to the image forming apparatus according to the twelfth aspect, in the structure in which the toner in the toner storage unit is supplied to the developing device by dropping in the vertical conveying path, the vertical conveying path is closed and the toner is merely a pipe. In comparison, deterioration in image quality is suppressed.

According to the image forming apparatus according to the thirteenth aspect, the structure is simple as compared with the configuration having a dedicated introducing means for introducing air into the vertical conveying path.

1 is a configuration diagram showing an image forming apparatus equipped with a toner conveying device according to a first embodiment; FIG. 2 is a longitudinal sectional view showing the developing device shown in FIG. 1; FIG. 1 is a configuration diagram showing a toner conveying device according to a first embodiment; FIG. 3 is a perspective view showing a vertical conveying path used in the toner conveying device according to the first embodiment; FIG. 3A is a front view showing a vertical conveying path used in the toner conveying device according to the first embodiment, and FIG. 4A is a side view showing the vertical conveying path used in the toner conveying device according to the first embodiment; FIG. 3 is a cross-sectional view showing a vertical conveying path used in the toner conveying device according to the first embodiment; FIG. FIG. 7 is a configuration diagram showing a toner conveying device according to a second embodiment; FIG. 11 is a perspective view showing a vertical conveying path used in a toner conveying device according to a third embodiment; FIG. 11 is a front view showing a vertical conveying path used in a toner conveying device according to a third embodiment; FIG. 11 is a cross-sectional view showing a vertical conveying path used in a toner conveying device according to a third embodiment; FIG. 11 is a front view showing a vertical conveying path used in a toner conveying device according to a fourth embodiment; FIG. 11 is a front view showing a vertical conveying path used in a toner conveying device according to a fifth embodiment; FIG. 11 is a perspective view showing a vertical conveying path used in a toner conveying device according to a sixth embodiment; FIG. 11 is a side view showing a vertical conveying path used in a toner conveying device according to a sixth embodiment; FIG. 11 is a perspective view showing a toner conveying device according to a seventh embodiment;

EMBODIMENT OF THE INVENTION Hereinafter, the form (henceforth this embodiment) for implementing this invention is demonstrated. In the following description, the direction indicated by arrow X in the drawings is the width direction of the device, and the direction indicated by arrow Y is the height direction of the device. A direction (arrow Z direction) orthogonal to each of the device width direction and the device height direction is defined as the device depth direction.

[First embodiment]
FIG. 1 shows an example of an image forming apparatus 10 equipped with a toner conveying device 150 of the first embodiment. First, the image forming apparatus (see FIG. 1) of this embodiment will be described. Next, the developing device 100 and the toner conveying device 150 will be described.

<Overall Configuration of Image Forming Apparatus>
As shown in FIG. 1, the image forming apparatus 10 includes a recording medium containing section 12, a toner image forming section 14, a transfer device 16, a recording medium conveying device 18, a fixing device 20, a control section 70, It is an electrophotographic apparatus comprising:

The recording medium containing section 12 has a function of containing a sheet of paper P as an example of a recording medium before an image is formed.

The toner image forming unit 14 has a function of performing charging, exposing, and developing processes to form a toner image held by an intermediate transfer belt 30 (described later) that constitutes the transfer device 16 . The toner image forming unit 14 is, for example, a monochromatic toner image forming toner image on each photoreceptor 22 using toners of different colors (Y (yellow), M (magenta), C (cyan), and K (black)). It has units 21Y, 21M, 21C and 21K. Further, the toner image forming section 14 can form a toner image composed of a plurality of colors, for example, according to image data. Here, the photoreceptor 22 is an example of an image carrier.

The single-color units 21Y, 21M, 21C, and 21K have the same configuration except for the colors of the toner images they form. In the following description, the alphabets (Y, M, C, K) of the single-color units 21Y, 21M, 21C, and 21K are omitted when there is no need to distinguish between the single-color units 21Y, 21M, 21C, and 21K and their components. Each monochromatic unit 21 includes a photosensitive member 22 , a charging device 24 , an exposure device 26 , a developing device 100 and a cleaning device 28 .

The transfer device 16 has a function of holding the toner image of each color formed by each single-color unit 21 and transferring it onto the paper P being conveyed. The transfer device 16 includes an intermediate transfer belt 30 , four transfer rolls 32 , a drive roll 38 , a secondary transfer portion 36 and a tension roll 34 . The intermediate transfer belt 30 is endless. The four transfer rolls 32 form nips with the photoreceptors 22 with the intermediate transfer belt 30 interposed therebetween. The intermediate transfer belt 30 is rotated in the direction of the arrow by the drive roll 38 . In this embodiment, as an example, the single-color units 21Y, 21M, 21C, and 21K are arranged in this order from the upstream side to the downstream side in the rotation direction of the intermediate transfer belt 30 . As a result, the toner images on the photosensitive member 22 formed by the single-color units 21Y, 21M, 21C, and 21K are superimposed and transferred onto the intermediate transfer belt 30 by the transfer roll 32. FIG.

The secondary transfer unit 36 includes a transfer roll 54 that contacts the surface of the intermediate transfer belt 30 on which the toner image is held, and a counter roll 56 that is arranged to face the transfer roll 54 with the intermediate transfer belt 30 interposed therebetween. I have. In the secondary transfer section 36, the toner images of each color held on the intermediate transfer belt 30 are transferred onto the paper P being conveyed.

The recording medium conveying device 18 has a function of conveying the paper P so that the paper P passes through the nip N<b>1 of the secondary transfer section 36 and the nip N<b>2 of the fixing device 20 . The recording medium conveying device 18 includes a plurality of conveying rolls 44 and a conveying belt 46 . The transport roll 44 is composed of a pair of rolls arranged in contact. The transport roll 44 transports the paper P accommodated in the recording medium accommodation unit 12 along the transport path 18A.

The conveying belt 46 has a structure in which an endless belt is wound around a pair of rolls arranged apart from each other. The transport belt 46 is arranged downstream of the secondary transfer section 36 in the transport direction of the paper P and upstream of the fixing device 20 . The transport belt 46 transports the paper P onto which the toner image has been transferred by the secondary transfer portion 36 to the fixing device 50 along the transport path 18A.

The fixing device 20 has a function of fixing the toner image transferred (secondarily transferred) onto the paper P by the transfer device 16 at the nip N2. The fixing device 20 includes a heating section 62 on which an endless belt circulates, and a pressure roll 64 that is pressed against the heating section 62 . By conveying the paper P to the nip N2 between the heating unit 62 and the pressure roll 64, the toner image on the paper P is fixed by heating and pressing.

The control section 70 has a function of controlling each section of the image forming apparatus 10 . For example, the control section 70 controls each section of the image forming apparatus 10 (causes each section to operate) according to job data received from an external device (not shown). Here, the job data includes image data (image information) for forming a toner image in each single color unit 21 and other data necessary for image forming operation.

<Operation of Image Forming Apparatus>
Next, operations of the image forming apparatus 10 will be described.

Upon receiving job data from an external device (not shown), the control unit 70 operates the toner image forming unit 14 , the transfer device 16 , the recording medium conveying device 18 and the fixing device 20 . In the toner image forming unit 14 , each photosensitive member 22 is charged by each charging device 24 , each photosensitive member 22 is exposed by each exposure device 26 to form an electrostatic latent image, and each developing device 100 charges each photosensitive member. The electrostatic latent image on body 22 is developed as a toner image. As a result, each toner image is formed on each photoreceptor 22 .

Next, a voltage (primary transfer voltage) is applied to each transfer roll 32 from a power supply (not shown). A drive roll 38 driven by a drive source (not shown) rotates the intermediate transfer belt 30 in the direction of the arrow. As a result, the toner images of each color are superimposed and primarily transferred onto the intermediate transfer belt 30 .

Further, the recording medium conveying device 40 feeds the paper P into the nip N1 in synchronization with the timing at which the toner images of each color held on the rotating intermediate transfer belt 30 reach the nip N1. In the secondary transfer unit 36, a voltage (secondary transfer voltage) is applied from a power supply (not shown) to a power supply roll (not shown) that contacts the outer periphery of the opposing roll 56, thereby feeding the paper P passing through the nip N1. A toner image of each color is secondarily transferred to the .

Next, the recording medium conveying device 40 feeds the paper P onto which the toner images of the respective colors have been secondarily transferred to the nip N2. As a result, the toner image of each color is fixed on the paper P passing through the nip N2 by the fixing device 20, thereby forming an image on the paper P. FIG. After that, the paper P is discharged to the discharge section 66 by the transport rolls 44 .

<Developing device>
Next, the developing device 100 will be described.

As shown in FIG. 2, the developing device 100 includes a housing 102 containing the developer G, a developing roll 106 holding the developer G, and a thickness of the layer of the developer G on the outer peripheral surface of the developing roll 106. It has a trimmer 108 as an example of a developer regulating member to regulate, and a developer agitating/conveying section 125 . The developer agitating/conveying section 125 has a first agitating/conveying chamber 123 and a second agitating/conveying chamber 124 adjacent to the first agitating/conveying chamber 123 . A first auger 109 is provided in the first agitating and conveying chamber 123 , and a second auger 111 is provided in the second agitating and conveying chamber 124 .

As shown in FIG. 2, the developer G includes, for example, two components including a toner T as an example of negatively charged charged particles and a magnetic carrier CA as an example of positively charged magnetic particles. Consists of developer.

The housing 102 includes a container body 103 and a cover member 104 that closes the top of the container body 103 . The housing 102 also includes a developing roll chamber 122 in which the developing roll 106 is housed, and a developer agitating/conveying section 125 (a first agitating/conveying chamber 123 and a second agitating/conveying chamber 123) provided obliquely below the developing roll chamber 122. 124) and .

The container body 103 has a partition wall 103A that separates the first stirring and conveying chamber 123 and the second stirring and conveying chamber 124 . The container main body 103 is provided with inlets (not shown) connected to the first stirring and conveying chamber 123 and the second stirring and conveying chamber 124 at both ends of the partition wall 103A in the Z direction.

The cover member 104 includes an upper wall 104A arranged above the second agitating and conveying chamber 124, an inclined wall 104B extending obliquely upward to the left from the left end of the upper wall 104A and covering the developing roll chamber 122, and an end of the upper wall 104A. and a fitting portion 104</b>C that extends downward from the portion and is fitted into the container body 103 . A trimmer 108 is attached to the inner surface of the inclined wall 104B.

Further, a developer supply port 136 is provided above the second agitating/conveying chamber 124 in the upper wall 104A. A lower end portion 154B of a vertical conveying path 154 (see FIG. 4) for supplying new toner T is connected to the developer supply port 136 . The cover member 104 and the vertical transport path 154 may be integrally formed, or may be formed separately and joined by adhesion or the like.

The developing roll 106 includes a magnet roll 106A which is cylindrically formed and fixedly supported by the container body 103 via a shaft 106C, and a cylindrical developing sleeve 106B which is rotatably supported outside the magnet roll 106A. ,have. A plurality of magnetic poles are provided along the outer peripheral surface (circumferential direction) of the magnet roll 106A.

The developer G in the first stirring/conveying chamber 123 is conveyed by the rotation of the developing sleeve 106B in the +R direction while being held on the developing sleeve 106B. Then, the developer G held on the developing sleeve 106B enters between the outer peripheral surface of the developing sleeve 106B and the tip portion 108A of the trimmer 108, thereby regulating the layer thickness and increasing the thickness of the photoreceptor 22 (see FIG. 1). ) is conveyed to the development area facing the .

The first auger 109 includes a rotating shaft 109A arranged along the Z direction, and a spiral conveying blade 109B supported on the outer periphery of the rotating shaft 109A. The first auger 109 rotates, for example, in the -R direction to stir and convey the developer G. As shown in FIG.

The second auger 111 has a rotating shaft 111A arranged along the Z direction, and a spiral conveying blade 111B supported on the outer periphery of the rotating shaft 111A. The second auger 111 rotates, for example, in the +R direction to stir and convey the developer G in the opposite direction to the first auger 109 . The rotation of the first auger 109 and the second auger 111 transports the developer G in the first stirring-transporting chamber 123 and the second stirring-transporting chamber 124 in opposite directions in the Z-axis direction. circulated. Then, the developer G conveyed by the first auger 109 is supplied to the developing roll 106 .

<Toner Conveying Device>
Next, the toner conveying device 150 of the first embodiment will be explained.

As shown in FIG. 1, the image forming apparatus 10 includes a plurality of toner cartridges 140Y and 140M each containing toner of a different color (Y (yellow), M (magenta), C (cyan), K (black)). , 140C and 140K. The image forming apparatus 10 also includes a plurality of toner conveying devices 150Y, 150M, 150C for conveying the toner T of each color from the toner cartridges 140Y, 140M, 140C, 140K to the developing devices 100 of the single-color units 21Y, 21M, 21C, 21K. It has 150K. Here, the toner cartridges 140Y, 140M, 140C, and 140K are an example of the toner containing portion.

The toner conveying devices 150Y, 150M, 150C and 150K and the toner cartridges 140Y, 140M, 140C and 140K have the same configuration except for the color of the toner stored or conveyed. In the following description, the toner conveying devices 150Y, 150M, 150C, and 150K and the toner cartridges 140Y, 140M, 140C, and 140K omit alphabets (Y, M, C, and K) when there is no need to distinguish between toner colors. do.

As shown in FIG. 3, the toner conveying device 150 is connected to a cylindrical horizontal conveying path 152 connected to the lower portion of the toner cartridge 140, and to the end of the horizontal conveying path 152 opposite to the toner cartridge 140. and a cylindrical vertical transport path 154 . The toner cartridge 140 has a tubular shape and includes an agitator 142 for conveying toner therein. As an example, the agitator 142 is configured such that a spiral member rotates.

The horizontal transport path 152 is arranged along the horizontal direction of the image forming apparatus 10 . The horizontal transport path 152 is configured to connect the toner cartridge 140 and the vertical transport path 154 . Here, the horizontal conveying path 152 is an example of a conveying path. An upstream end 152A of the horizontal transport path 152 is connected to an axial end 140A of the toner cartridge 140 . The horizontal transport path 152 extends above the vertical transport path 154 in a direction crossing the vertical transport path 154 (horizontal direction in this embodiment). A conveying member 156 that conveys the toner T along the horizontal conveying path 152 is provided inside the horizontal conveying path 152 . The horizontal transport path 152 may be arranged so as to have a slight downward slope from the upstream end 152A toward the downstream end 152B.

The conveying member 156 has a rotating shaft 156A arranged along the longitudinal direction (Z direction) of the horizontal conveying path 152, and a spiral conveying blade 156B supported on the outer periphery of the rotating shaft 156A. The conveying member 156 conveys the toner introduced from the toner cartridge 140 toward the vertical conveying path 154 by rotating the rotating shaft 156A.

The vertical transport path 154 is arranged along the vertical direction. The upper end portion 154A of the vertical transport path 154 is connected to the lower wall of the downstream end portion 152B of the horizontal transport path 152 . A lower end portion 154B of the vertical conveying path 154 is coupled (connected) to the upper wall 104A of the second stirring conveying chamber 124 of the developing device 100 (see FIG. 2). That is, the upper end 154A of the vertical transport path 154 is the upstream end, and the lower end 154B of the vertical transport path 154 is the downstream end. Although not shown, the lower end portion 154B of the vertical transport path 154 is connected to the upstream end portion of the second stirring transport chamber 124 of the developing device 100 in the longitudinal direction (Z direction). Note that the internal configuration of the developing device 100 is omitted in FIG. The vertical conveying path 154 causes the toner conveyed from the horizontal conveying path 152 to drop from the upper end portion 154A, thereby guiding (supplying) the toner to the developing device 100 vertically downward.

Here, in the vertical transport path 154, the direction (axial direction) of the central portion is shifted from the vertical direction by a predetermined angle, in addition to the case where the direction (axial direction) of the central portion is arranged in the vertical direction. Including cases. For example, the angle θ of the vertical transport path 154 with respect to the vertical direction is preferably 0° or more and 20° or less, and more preferably 0° or more and 10° or less. In this case, it is preferable that the through portion at the upper end of the vertical transport path 154 and the through portion at the lower end of the vertical transport path 154 overlap in the vertical direction. That is, in the vertical conveying path of the present invention, "to guide (the toner) downward in the vertical direction" includes a horizontal shift as long as there is a component in the vertical direction.

As shown in FIGS. 4 and 5A and 5B, the vertical transport path 154 includes a cylindrical side wall portion 160 arranged along the vertical direction and a through hole provided inside the side wall portion 160. The toner is conveyed through the through portion 162 of the vertical conveying path 154 . Here, the side wall portion 160 is an example of a cylinder wall. In this embodiment, the side wall portion 160 of the vertical transport path 154 is circular. The diameter D1 of the lower end portion 154B of the vertical transport path 154 is larger than the diameter D2 of the upper end portion 154A of the vertical transport path 154 (see FIG. 4). In other words, in the vertical transport path 154, the opening area of the through portion 162 (toner outlet) on the side of the vertical lower end portion 154B is larger than the opening area of the through portion 162 (toner inlet) on the side of the vertical upper end portion 154A. big. In this embodiment, the inner diameter of the through portion 162 of the vertical transport path 154 gradually (continuously) increases from the upper end portion 154A toward the lower end portion 154B.

The ratio of the opening area of the through portion 162 (toner inlet) on the upper end portion 154A side of the vertical transport path 154 to the opening area of the through portion 162 (toner outlet) on the lower end portion 154B side of the vertical transport path 154 is 154 may be changed depending on the length in the vertical direction. For example, when the length of the vertical transport path 154 in the vertical direction is long, compared to the case where the length of the vertical transport path 154 in the vertical direction is short, the opening area of the through portion 162 on the lower end portion 154B side of the vertical transport path 154 is larger. The opening area ratio of the through portion 162 on the upper end portion 154A side of the vertical transport path 154 may be reduced.

Further, an inflow pipe 158 for introducing air into the vertical transport path 154 as indicated by an arrow A is provided on the upper end portion 154A side of the side wall portion 160 of the vertical transport path 154 . A through hole 159 that communicates with the through portion 162 of the vertical transport path 154 is provided inside the inflow pipe 158 (see FIGS. 5B and 6). Here, the inflow pipe 158 is an example of an inflow port. The inflow pipe 158 is provided along the normal direction of the side wall portion 160 of the vertical transport path 154 . Also, the inflow pipe 158 extends horizontally from the side wall portion 160 of the vertical transport path 154 .

As shown in FIG. 3, the image forming apparatus 10 has a circulation device 170 as an example of circulation means for introducing the air inside the developing device 100 into the vertical conveying path 154 . The circulation device 170 has a pipe 172 that connects the developing device 100 and the inflow pipe 158 (see FIG. 4) of the vertical transport path 154 . In the image forming apparatus 10 , the internal pressure of the developing device 100 is generally higher than the external pressure of the developing device 100 inside the image forming apparatus 10 and the internal pressure of the vertical transport path 154 . Therefore, due to the internal pressure of the developing device 100, the air in the developing device 100 is introduced from the inflow pipe 158 into the vertical conveying path 154 via the pipe 172, that is, the air is circulated. In general, a developing device is provided with a pressure relief hole in order to reduce the internal pressure of the developing device. .

The air introduced into the vertical transport path 154 from the inflow pipe 158 does not easily flow toward the horizontal transport path 152 because the toner density is high at the downstream end 152B of the horizontal transport path 152 due to the transport of the toner. . Therefore, the air introduced into the vertical conveying path 154 from the inflow pipe 158 flows toward the developing device 100 side. Air is introduced from the developing device 100 into the vertical transport path 154 through the pipe 172 of the circulation device 170, so that the air is circulated between the developing device 100 and the vertical transport path 154. .

As shown in FIG. 6, the air introduced from the inflow pipe 158 into the vertical conveying path 154 in the direction of the arrow A hits the inner wall 161 of the side wall portion 160 facing the inflow pipe 158 and hits the inner wall 161 of the side wall portion 160. along the arrow B direction. When the toner falls from the upper end portion 154A of the vertical conveying path 154 toward the lower end portion 154B, the toner collides with the air introduced from the inflow pipe 158 while falling.

<Action and effect>
Next, the operation and effects of this embodiment will be described.

The toner conveying device 150 is provided with a cylindrical vertical conveying path 154 that guides the toner conveyed from the toner cartridge 140 through the horizontal conveying path 152 downward in the vertical direction. is connected to the developing device 100 at its lower end portion 154B. A conveying member 156 is provided inside the horizontal conveying path 152 , and the toner introduced into the horizontal conveying path 152 from the toner cartridge 140 is conveyed toward the vertical conveying path 154 by the rotation of the conveying member 156 . At the downstream end 152</b>B of the horizontal conveying path 152 , the toner density increases as the toner is conveyed by the conveying member 156 .

When the toner is transported from the horizontal transport path 152 to the upper end 154A of the vertical transport path 154, the toner falls from the upper end 154A of the vertical transport path 154 toward the lower end 154B. An inflow pipe 158 is provided on the upper end portion 154A side of the vertical transport path 154 , and air is introduced (flowed) into the vertical transport path 154 from the inflow pipe 158 . The air introduced into the vertical transport path 154 flows toward the center of the vertical transport path 154 and collides with the falling toner. For example, when the toner conveyed from the horizontal conveying path 152 contains aggregated toner, the aggregated toner collides with the air introduced from the inflow pipe 158 and is loosened by air agitation. That is, the aggregated toner is broken up, and the vertical conveying path 154 is less likely to be clogged with toner.

In the toner conveying device 150 described above, the toner in the toner containing portion is supplied to the developing device by falling in the vertical conveying path, and the vertical conveying path is simply a tube closed (simple tube without an inlet). Clogging of toner falling down the vertical conveying path 154 is suppressed as compared with .

In the toner conveying device 150, the vertical conveying path 154 has a toner outlet opening area on the vertical lower end portion 154B side larger than a toner inlet opening area on the vertical upper end portion 154A side. In the toner conveying device 150, the toner is loosened by the air introduced into the vertical conveying path 154 and tends to land in a wide range, compared to the case where the toner simply falls within the vertical conveying path. For this reason, in the toner conveying device 150, toner is less likely to clog the lower end portion 154B of the vertical conveying path 154 compared to a configuration in which the inner diameter of the vertical conveying path is constant along the vertical direction.

Further, in the toner conveying device 150 , a horizontal conveying path 152 extending in a direction crossing the vertical conveying path 154 above the vertical conveying path 154 and connected to the toner cartridge 140 is provided. A conveying member 156 is provided inside the horizontal conveying path 152 , and the toner is conveyed through the horizontal conveying path 152 by the conveying member 156 . Therefore, in the toner conveying device 150, in a configuration in which the toner density increases as the toner is conveyed to the vertical conveying path 154, clogging of toner is suppressed.

Further, in the toner conveying device 150 , an inflow pipe 158 for introducing air is provided along the normal line direction of the side wall portion 160 of the vertical conveying path 154 . As a result, air flows from the inflow pipe 158 toward the central portion of the vertical transport path 154, and the toner falling down the vertical transport path 154 collides with the air. For this reason, in the toner conveying device 150, aggregated toner is easily loosened compared to a configuration in which air is introduced downward from the upper portion of the vertical conveying path.

Further, in the image forming apparatus 10 , the toner is supplied to the developing device 100 after being loosened in the vertical conveying path 154 of the toner conveying device 150 . As a result, the developer G replenished with new toner is easily agitated in the developing device 100, and the toner is prevented from being low-charged due to insufficient agitation of the toner. For this reason, in the image forming apparatus 10, in the structure in which the toner in the toner storage unit is supplied to the developing device by falling in the vertical conveying path, compared to a simple tube in which the vertical conveying path is closed, Image quality degradation due to insufficient toner agitation is suppressed.

Furthermore, the image forming apparatus 10 is provided with a circulation device 170 that introduces the air in the developing device 100 from the inflow pipe 158 into the vertical transport path 154 via the pipe 172 by the internal pressure of the developing device 100 . For this reason, the image forming apparatus 10 has a simpler structure than a configuration having dedicated introduction means for introducing air into the vertical conveying path. Furthermore, the image forming apparatus 10 consumes less energy than a configuration having dedicated introduction means for introducing air into the vertical conveying path.

[Second embodiment]
FIG. 7 shows an example of the toner conveying device 180 of the second embodiment. In addition, about the same component part as 1st Embodiment mentioned above, the same number is attached and the description is abbreviate|omitted.

As shown in FIG. 7, the toner conveying device 180 includes an air pump 182 as an example of introducing means for introducing air into the vertical conveying path 154 instead of the circulation device 170 (see FIG. 3) of the first embodiment. It has The air pump 182 is connected to the inflow pipe 158 of the vertical transport path 154 via a pipe 184 . The air pump 182 has a fan (not shown), and the rotation of the fan introduces air into the vertical transport path 154 through the pipe 184 and the inflow pipe 158 .

The toner conveying device 180 described above has the following actions and effects in addition to the actions and effects of the configuration similar to that of the toner conveying device 150 (see FIG. 3) of the first embodiment.

The toner conveying device 180 is provided with an air pump 182 that introduces air into the vertical conveying path 154 via a pipe 184 and an inflow pipe 158 . Therefore, in the toner conveying device 180 , air can be introduced into the vertical conveying path 154 by the air pump 182 . Also, the air pump 182 enables setting and adjustment of the amount of air to be introduced.

[Third embodiment]
8 to 10 show a vertical conveying path 192 used in the toner conveying device 190 of the third embodiment. It should be noted that the same components as those of the above-described first and second embodiments are assigned the same numbers and the description thereof will be omitted.

As shown in FIGS. 8 to 10, the toner conveying device 190 has an inflow pipe 194 which introduces air into the vertical conveying path 192 in the direction of arrow C on the upper end portion 154A side of the side wall portion 160 of the vertical conveying path 192. It has A through hole 195 is formed inside the inflow pipe 194 , and the through hole 195 is connected to the through portion 162 of the vertical transport path 192 . Here, the inflow pipe 194 is an example of an inflow port. A through hole 195 of the inflow pipe 194 is provided along an inner wall 196 of the side wall portion 160 of the vertical transport path 192 (see FIG. 10). Other configurations of the toner conveying device 190 are the same as those of the toner conveying device 150 of the first embodiment.

The toner conveying device 190 described above has the following actions and effects in addition to the actions and effects of the same configuration as the toner conveying device 150 (see FIG. 3) of the first embodiment.

As shown in FIG. 10, the air introduced from the inflow pipe 194 into the vertical transport path 192 in the direction of arrow C flows along the circular inner wall 196 of the vertical transport path 192 and flows in the direction of arrow D in a spiral. Therefore, even if the toner is agglomerated, the agglomerated toner falling down the vertical conveying path 192 is loosened (broken) by the swirl. For this reason, in the toner conveying device 190, aggregated toner falling down the vertical conveying path 192 is easily loosened compared to a configuration in which air is introduced downward from the upper portion of the vertical conveying path. In particular, the configuration in which the inflow pipe 194 of the toner transport device 190 is provided along the inner wall 196 of the vertical transport path 192 is the configuration in which the inflow pipe 158 of the toner transport device 150 is provided along the normal direction of the vertical transport path 154 (see FIG. 4). etc.), it is effective when the inner diameter of the vertical transport path 192 is small.

[Fourth embodiment]
FIG. 11 shows a vertical conveying path 202 used in the toner conveying device 200 of the fourth embodiment. The same reference numerals are assigned to the same components as those of the first to third embodiments described above, and the description thereof will be omitted.

As shown in FIG. 11, the toner conveying device 200 includes a plurality of inflow pipes for introducing air into the vertical conveying path 202 at the upper end portion 154A side and the vertically intermediate portion of the side wall portion 160 of the vertical conveying path 202. 158 are provided. In this embodiment, the inflow pipes 158 are provided at two locations apart in the vertical direction of the vertical transport path 202 . Also, the two inflow pipes 158 are aligned along the vertical direction of the vertical transport path 202 . The two inflow pipes 158 are provided along the normal direction of the side wall portion 160 of the vertical transport path 202 . Other configurations of the toner conveying device 190 are the same as those of the toner conveying device 150 of the first embodiment.

The toner conveying device 200 described above has the following actions and effects in addition to the actions and effects of the same configuration as the toner conveying device 150 (see FIG. 3) of the first embodiment.

In the toner conveying device 200 , two inflow pipes 158 are provided on the side wall portion 160 of the vertical conveying path 202 . As a result, when the toner falls down the vertical conveying path 202, it collides with the air introduced from the two inflow pipes 158 arranged at vertically separated positions. For this reason, in the toner conveying device 200, aggregated toner falling down the vertical conveying path 202 is easily loosened compared to a configuration in which only one air inlet is provided in the vertical conveying path.

[Fifth embodiment]
FIG. 12 shows a vertical conveying path 212 used in the toner conveying device 210 of the fifth embodiment. It should be noted that the same components as those of the above-described first to fourth embodiments are assigned the same numbers, and description thereof will be omitted.

As shown in FIG. 12, the toner conveying device 210 has two inflow pipes for introducing air into the vertical conveying path 212 at the upper end portion 154A side and the vertical middle portion of the side wall portion 160 of the vertical conveying path 212. 158, 194 are provided. In this embodiment, the two inflow pipes 158 and 194 are arranged on the side wall portion 160 of the vertical transport path 212 with their positions shifted in the vertical direction. One inflow pipe 158 is provided along the normal line direction of the side wall portion 160 of the vertical transport path 212 . A through hole 195 of the other inflow pipe 194 is provided along the inner wall (not shown) of the side wall portion 160 of the vertical transport path 192 . Other configurations of the toner conveying device 190 are the same as those of the toner conveying device 150 of the first embodiment.

The toner conveying device 210 described above has the following actions and effects in addition to the actions and effects of the same configuration as the toner conveying device 150 (see FIG. 3) of the first embodiment.

In the toner conveying device 210, the two inflow pipes 158 and 194 are arranged on the side wall portion 160 of the vertical conveying path 212 with their positions shifted in the vertical direction. As a result, when the toner falls down the vertical conveying path 202, it collides with the air introduced from the two inflow pipes 158 and 194 which are displaced in the vertical direction. For this reason, in the toner conveying device 210, aggregated toner falling down the vertical conveying path 212 is easily loosened compared to a configuration in which a plurality of inlets are provided at the same position in the vertical direction of the vertical conveying path.

[Sixth embodiment]
13 and 14 show a vertical conveying path 222 used in the toner conveying device 220 of the sixth embodiment. The same reference numerals are assigned to the same components as those of the first to fifth embodiments described above, and the description thereof will be omitted.

As shown in FIGS. 13 and 14, the toner conveying device 220 has an inflow pipe 224 extending obliquely upward from the side wall portion 160 on the side of the upper end portion 154A of the vertical conveying path 222 . A through hole 225 that communicates with the through portion 162 of the vertical transport path 222 is provided inside the inflow pipe 224 . Here, the inflow pipe 224 is an example of an inflow port. The air introduced into the vertical conveying path 222 from the inflow pipe 224 flows obliquely below the vertical conveying path 222 along the flow direction of the inflow pipe 224, hits the inner wall of the through portion 162 of the vertical conveying path 222, and is divided. be done. The angle of the inflow pipe 224 with respect to the virtual line on the upper side in the vertical direction of the vertical transport path 222 is preferably greater than 0 and less than 60 degrees, and more preferably greater than 10 degrees and less than 45 degrees.

The toner conveying device 220 described above has the following actions and effects in addition to the actions and effects of the configuration similar to that of the toner conveying device 150 (see FIG. 3) of the first embodiment.

The toner conveying device 220 is provided with an inflow pipe 224 extending obliquely upward from the side wall portion 160 of the vertical conveying path 222 . As a result, the air introduced into the vertical transport path 222 from the inflow pipe 224 flows obliquely downward along the vertical transport path 222 along the flow direction of the inflow pipe 224 and collides with the toner falling down the vertical transport path 222 . do. For this reason, in the toner conveying device 220, aggregated toner falling down the vertical conveying path 222 is more easily loosened compared to a configuration in which the toner conveying device 220 extends obliquely downward from the cylindrical wall of the vertical conveying path.

[Seventh embodiment]
FIG. 15 shows the toner conveying device 230 of the seventh embodiment. The same reference numerals are assigned to the same components as those of the first to sixth embodiments described above, and the description thereof will be omitted.

The toner conveying device 230 includes a conveying member 156 that conveys toner inside the horizontal conveying path 152 . The conveying member 156 includes a rotating shaft 156A and a spiral conveying blade 156B supported on the outer periphery of the rotating shaft 156A. A crank 232 is formed near the downstream end of the rotating shaft 156A. . The crank 232 includes a crank pin 232A whose axis is parallel to the rotation shaft 156A, and arm portions 232B and 232C that connect both ends of the crank pin 232A and the rotation shaft 156A.

Further, inside the side wall portion 160 of the vertical transport path 154, a collapsing member 236 in which a linear member is wound in a coil shape is provided. At the upstream end of the collapsing member 236, a bent portion 236A bent in a U-shape is provided. The bent portion 236A is hooked on the crank pin 232A of the crank 232 of the conveying member 156. As shown in FIG.

In the toner conveying device 220, the conveying member 156 of the horizontal conveying path 152 is rotated by a drive means such as a motor (not shown). When the conveying member 156 rotates, toner supplied from a toner cartridge (not shown) is conveyed from the upstream end 152A of the horizontal conveying path 152 toward the downstream end 152B. When the toner reaches the vertical conveying path 154 , the toner drops down the vertical conveying path 154 and is supplied to the developing device 100 . Note that an arrow S in the drawing indicates the direction in which the toner is conveyed.

Further, along with the rotation of the rotating shaft 156A of the conveying member 156 of the horizontal conveying path 152, the breaking member 236, in which the bent portion 236A is attached to the crank pin 232A of the crank 232 of the rotating shaft 156A, moves up and down (moves in the vertical direction). )do.

The toner conveying device 210 described above has the following actions and effects in addition to the actions and effects of the same configuration as the toner conveying device 150 (see FIG. 3) of the first embodiment.

In the toner conveying device 210, a coil-shaped crushing member 236 for crushing toner is provided inside the vertical conveying path 154. As shown in FIG. For this reason, in the toner conveying device 210, the aggregated toner falling down the vertical conveying path 154 is more easily loosened than in the case where the vertical conveying path is hollow.

Further, in the toner conveying device 210, the breaking member 236 moves vertically as the rotation shaft 156A of the conveying member 156 rotates. For this reason, in the toner conveying device 210, the aggregated toner falling down the vertical conveying path 154 is easily loosened compared to the configuration in which the breaking member rotates.

〔supplementary explanation〕
The toner conveying devices 190, 200, 210, 220, and 230 of the third to seventh embodiments are provided with the circulation device 170 for introducing air into the vertical conveying path, but the present invention is not limited to this configuration. Absent. For example, instead of the circulating device 170, an introduction means such as an air pump 182 may be used to introduce air into the vertical conveying path.

In the toner conveying device 200 of the fourth embodiment, two inflow pipes 158 are provided in the vertical conveying path 202, but the number and positions of the inflow pipes 158 can be changed. For example, the vertical transport path may be provided with three or more inflow pipes.

In the toner conveying device 210 of the fifth embodiment, the two inflow pipes 158, 194 are provided in the vertical conveying path 202, but the number, positions, types, etc. of the inflow pipes 158, 194 may be changed. For example, three or more inflow pipes of the same type or different types may be provided by shifting their positions in the vertical direction.

In the toner conveying device 220 of the sixth embodiment, the inflow pipes 224 extending obliquely upward from the vertical conveying path 222 are provided, but the number, positions, types, etc. of the inflow pipes 224 may be changed. For example, two or more inflow pipes extending obliquely upward from the vertical transport path may be provided in the vertical direction. Also, the angle of the inflow pipe 224 with respect to the virtual line above the vertical transport path 222 may be changed. Also, one or more inflow pipes extending obliquely upward from the vertical transport path may be provided along the inner wall of the cylinder wall of the vertical transport path.

In the toner conveying devices 150, 180, 190, 200, 210, 220, and 230 of the first to seventh embodiments, the inner diameter of the vertical conveying path gradually increases from the upper end portion 154A toward the lower end portion 154B. However, the present invention is not limited to this. For example, the inner diameter of the through portion of the vertical transport path may be increased stepwise. A configuration including a part may be used.

Although the present invention has been described in detail with respect to particular embodiments, it should be understood that the invention is not limited to such embodiments and that various other embodiments are possible within the scope of the invention. clear to the trader.

10 image forming device 16 transfer device 22 photoreceptor (an example of an image carrier)
100 Developing device 140 Toner cartridge (an example of a toner container)
150 toner transport device 152 horizontal transport path (an example of a transport path)
154 Vertical conveying path 156 Conveying member 158 Inflow pipe (an example of an inflow port)
160 side wall (an example of a cylinder wall)
170 circulation device (an example of circulation means)
180 toner conveying device 182 air pump (an example of introducing means)
190 toner conveying device 192 vertical conveying path 194 inflow pipe (an example of an inflow port)
196 Inner wall 200 Toner conveying device 202 Vertical conveying path 210 Toner conveying device 212 Vertical conveying path 220 Toner conveying device 222 Vertical conveying path 224 Inflow pipe (an example of an inflow port)
230 toner conveying device 236 breaking member P paper (an example of a recording medium)

Claims (13)

A cylindrical vertical conveying path that guides the toner from the toner container downward in the vertical direction and is connected to the developing device vertically downward, wherein the connecting portion to the developing device is arranged vertically downward. and the vertical transport path that is
an inlet through which air flows into the interior of the vertical transport path from a cylindrical wall of the vertical transport path;
has
Toner conveyed from the toner storage unit by a conveying member is supplied to the vertical conveying path,
The toner is conveyed to the developing device by falling on the vertical conveying path,
A toner conveying device configured such that air is introduced through the inlet from a direction different from the falling direction of the toner in the vertical conveying path . 2. The toner conveying device according to claim 1, wherein the opening area of the toner outlet at the lower end in the vertical direction of the vertical conveying path is larger than the opening area of the toner inlet at the upper end in the vertical direction. a conveying path extending above the vertical conveying path in a direction intersecting the vertical conveying path, connecting the toner storage unit and the vertical conveying path, and conveying toner;
a conveying member provided inside the conveying path for conveying toner along the conveying path;
3. The toner conveying device according to claim 1, comprising: 4. The toner conveying device according to claim 1, wherein the inlet is tubular and provided along the normal direction of the cylinder wall of the vertical conveying path. 4. The toner conveying device according to any one of claims 1 to 3, wherein the inlet is tubular and provided along the inner wall of the cylinder wall of the vertical conveying path. 6. The toner conveying device according to claim 1, wherein said inlet is tubular and extends obliquely upward from a cylindrical wall of said vertical conveying path. 7. The toner conveying device according to any one of claims 1 to 6, wherein a plurality of the inlets are provided in the cylindrical wall of the vertical conveying path. 8. The toner conveying device according to claim 7, wherein the plurality of inlets are arranged on the cylindrical wall of the vertical conveying path with their positions shifted in the vertical direction. 9. The toner conveying device according to claim 1, wherein a coil-shaped crushing member for crushing toner is provided inside said vertical conveying path. 10. A toner conveying device according to claim 9, wherein said breaking member is configured to move vertically. 11. The toner conveying device according to any one of claims 1 to 10, further comprising introducing means connected to said inlet for introducing air into said vertical conveying path. a toner conveying device according to any one of claims 1 to 11;
a developing device connected to the vertical conveying path of the toner conveying device;
an image carrier on which a toner image is formed by the toner of the developing device;
a transfer device that transfers the toner image of the image carrier onto a recording medium;
An image forming apparatus having The toner conveying device according to any one of claims 1 to 10,
13. An image forming apparatus according to claim 12, further comprising a circulation means connected to said developing device and said inlet, and for circulating air in said developing device from said inlet into said vertical conveying path by means of internal pressure of said developing device. Device.

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