JP2019056785A - Powder conveying device and image forming apparatus - Google Patents

Abstract

To provide a powder conveying device that reduces a manufacturing cost compared with a case where a middle part of a coil auger is fixed to a shaft.SOLUTION: A powder conveying device comprises: a powder conveyance path that is formed by metal pipes and resin pipes connected in a straight line state; and a sequence of coil augers that is formed into a spiral shape to rotate inside the conveyance path and convey a powder, and forms a second area inside the metal pipes in which a gap between an inner peripheral surface of the conveyance path and the coil auger is larger than that of a first area in the direction in which the conveyance path extends.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a powder conveying apparatus and an image forming apparatus for conveying powder.

  Patent Document 1 discloses a toner conveying device. The toner conveying device conveys the toner collected from the photoconductor cleaning device that collects the toner remaining on the image carrier to a waste toner tank provided in the main body of the image forming apparatus. The toner conveyance device includes a conveyance path that communicates with each photosensitive member cleaning device and the waste toner tank, and a conveyance member that is rotatably provided in the conveyance path and is rotationally driven by a drive source. The conveying member has an axis extending along the conveying path, and a spiral member whose axis passes through the center in the axial direction, and the spiral member is at least one positioned between the both end portions thereof. More than the part is fixed to the shaft.

JP2015-225173A

Thus, in order to suppress the contact with the metal pipe due to the bending of the metal coil auger, it is conceivable to pass the shaft through the center of the coil auger and fix the midway portion to the shaft.
An object of this invention is to provide the powder conveying apparatus which suppressed the manufacturing cost compared with the case where the middle part of a coil auger is fixed to an axis | shaft.

  The invention of claim 1 is formed by connecting a metal pipe and a resin pipe in a straight line, a powder conveyance path, and a spiral shape that rotates in the conveyance path and conveys powder, A powder carrier comprising: a continuous coil auger in which a gap between the inner circumferential surface of the conveying path and a second region larger than the first region in the extending direction of the conveying path is formed in the metal pipe. Device.

  A second aspect of the present invention is the powder conveying apparatus according to the first aspect, wherein the second region is formed by making an inner diameter of the metal pipe forming the conveying path larger than other portions of the conveying path.

  A third aspect of the present invention is the powder according to the first aspect, wherein the second region is formed by providing a small-diameter portion having an outer diameter smaller than that of the other portion at a portion of the coil auger disposed in the metal pipe. It is a transport device.

  A fourth aspect of the present invention is the powder conveying apparatus according to the third aspect, wherein the entire area of the coil auger portion disposed in the metal pipe is the small diameter portion.

  According to a fifth aspect of the present invention, the conveying path includes a plurality of the metal pipes, and the small diameter portion is provided in all of the portions of the coil auger disposed in each of the metal pipes. It is a powder conveyance apparatus of Claim 4.

  According to a sixth aspect of the present invention, the resin pipe is provided at both ends of the metal pipe, and a portion of the coil auger disposed in the resin pipe on both sides of the metal pipe has a larger diameter than the small diameter portion. It is a powder conveying apparatus as described in any one of Claim 3 to 5.

  According to a seventh aspect of the present invention, one of the resin pipes on both sides of the metal pipe has a powder outlet on a side surface, and at least a portion of the coil auger corresponding to the outlet is from the small diameter portion. It is a powder conveyance apparatus of Claim 6 made into the large diameter.

  The invention according to claim 8 is the powder conveying apparatus according to claim 3, wherein at least a part of the coil auger arranged in the metal pipe is the small diameter portion.

  According to a ninth aspect of the present invention, in the conveyance path according to the eighth aspect, the conveyance path includes a plurality of the metal pipes, and the small diameter portion is provided at a portion of the coil auger disposed in a part of the metal pipes. It is a powder conveying device.

  According to a tenth aspect of the present invention, in the ninth aspect, the small-diameter portion is set at a portion of the coil auger disposed in the metal pipe having the longest length in the powder conveying direction among the plurality of metal pipes. This is a powder conveying device.

  According to an eleventh aspect of the present invention, the small diameter portion and a portion having a larger diameter than the small diameter portion are provided at a portion of the coil auger disposed in the metal pipe. It is a powder conveyance apparatus as described in above.

  A twelfth aspect of the present invention is the powder conveying apparatus according to the eleventh aspect, wherein the small diameter portion is provided at a central portion in the length direction of the metal pipe.

  According to a thirteenth aspect of the present invention, at least a part of a portion of the coil auger disposed in the resin pipe has a larger diameter than the small diameter portion. It is a powder conveying device.

  The invention according to claim 14 is characterized in that at least a part of the resin pipe has a joining portion for receiving and joining powders from the other on the side surface, and the portion of the coil auger corresponding to the joining portion is the small diameter portion. It is a powder conveyance apparatus of Claim 13 made larger diameter.

  According to a fifteenth aspect of the present invention, in the powder conveyance according to any one of the third to fifth aspects, the small-diameter portion is formed up to an end of the coil auger, and the outer diameter is changed at one location. Device.

  The invention of claim 16 is the powder conveying apparatus according to claim 15, wherein the changed portion is arranged at a boundary between the metal pipe and the resin pipe.

  According to a seventeenth aspect of the present invention, the resin pipe is provided with a merging portion that merges with the other, and a portion of the coil auger corresponding to the merging portion has a larger diameter than the small diameter portion. It is a powder conveying apparatus of Claim 16.

  According to an eighteenth aspect of the present invention, a resin supply pipe having an open supply port for supplying powder is provided, and the portion of the coil auger corresponding to the supply port is rotated to the supply port as the coil auger rotates. It is a powder conveyance apparatus as described in any one of Claims 1-17 provided with the vibration generation part made to vibrate toward.

  The invention according to claim 19 is the powder conveying device according to claim 18, wherein the vibration generating portion is constituted by a coil side protrusion protruding laterally from the coil auger.

  According to a twentieth aspect of the present invention, the vibration generating portion protrudes from the inner peripheral surface of the conveyance path toward the coil auger and is disposed between the spirally wound linear members constituting the coil auger. The powder conveyance device according to claim 18 or 19, comprising a conveyance path side protrusion.

  In a twenty-first aspect of the present invention, a plurality of the conveyance path side protrusions are provided in the length direction of the coil auger, and the interval between the adjacent conveyance path side protrusions is a non-integer of the winding pitch of the linear member wound spirally. It is a powder conveyance apparatus of Claim 20 made into the double size.

  According to a twenty-second aspect of the present invention, there is provided a conveyance path in which a part of the powder conveyance path is formed of a metal pipe, and a spiral shape that rotates in the conveyance path to convey the powder. The powder conveyance device includes a coil auger having a gap with a peripheral surface that is small at the end in the direction in which the conveyance path extends and large at the center.

  An invention according to claim 23 is an image forming unit that forms an image on a recording medium using toner, and a powder conveying device according to any one of claims 1 to 22 that conveys the toner as powder. An image forming apparatus.

  According to the first aspect of the present invention, it is possible to obtain a powder conveying apparatus with reduced manufacturing cost as compared with the case where the middle part of the coil auger is fixed to the shaft.

  According to the second aspect, the coil auger can be easily manufactured as compared with the case where a part of the coil auger has a small diameter.

  According to the third aspect, compared with the case where the diameter of the metal pipe is larger than that of the resin pipe, the level difference that can occur at the connection portion with the end of the metal pipe is suppressed.

  According to the fourth aspect of the present invention, the interference of the coil auger with the metal pipe is suppressed as compared with the case where a part of the metal pipe has a small diameter portion.

  According to the fifth aspect, in all the metal pipes, the interference between the coil auger and the metal pipe is suppressed as compared with the case where the coil auger has no small diameter portion.

  According to the sixth aspect, the center line of the coil auger can be brought closer to the center line of the conveyance path as compared with the case where the portion of the coil auger arranged in the resin pipe is a small diameter portion.

  According to the seventh aspect, powder clogging in the vicinity of the outlet is suppressed as compared with the case where the portion of the coil auger corresponding to the outlet is a small diameter portion.

  According to the eighth aspect, it is possible to increase the conveying capacity as compared with the case where the entire area of the coil auger arranged in the metal pipe is a small diameter portion.

  According to the ninth aspect, the shape of the coil auger can be simplified as compared with the case where all the portions of the coil auger arranged in the metal pipe are small diameter portions.

  According to the tenth aspect, compared with the case where the small diameter portion is set only at the portion of the coil auger disposed in the relatively short metal pipe, the interference suppression effect on the metal pipe due to the looseness of the coil auger is reduced. Will increase.

  According to the eleventh aspect, it is possible to increase the powder conveying ability as compared with the case where the inside of the metal pipe is constituted by only the small diameter portion.

  According to the twelfth aspect, it is possible to suppress the interference of the central portion with the metal pipe due to the slack compared with the case where the central portion in the length direction of the metal pipe is the large diameter portion.

  According to the thirteenth aspect, the center line of the coil auger can be brought closer to the center line of the conveyance path as compared with the case where the portion of the coil auger arranged in the resin pipe is a small diameter portion.

  According to the fourteenth aspect, powder clogging at the merging portion can be suppressed as compared with the case where the portion of the coil auger corresponding to the merging portion is a small diameter portion.

  According to the fifteenth aspect, the coil auger can be easily manufactured as compared with the case where a plurality of change locations where the outer diameter is changed are set.

  According to the sixteenth aspect, the interference of the coil auger to the metal pipe is suppressed as compared with the case where the changed portion where the outer diameter is changed is not disposed at the boundary between the metal pipe and the resin pipe.

  According to the seventeenth aspect, powder clogging at the merging portion can be suppressed as compared with the case where the portion of the coil auger corresponding to the merging portion is a small diameter portion.

  According to the eighteenth aspect, powder clogging in the vicinity of the supply port can be suppressed as compared with a case where no vibration generating unit that vibrates the coil auger is provided.

  According to the nineteenth aspect, the forming cost of the supply pipe can be reduced as compared with the case of processing the supply pipe.

  According to the twentieth aspect, the coil auger can be easily processed as compared with the case where the coil auger is processed.

  According to the twenty-first aspect, the coil auger can be expanded and contracted between the adjacent conveyance path side projections as compared with the case where the interval between the conveyance path side projections is the same as the winding pitch.

  According to the twenty-second aspect, it is possible to obtain a powder conveying apparatus with reduced manufacturing cost compared to the case where the middle part of the coil auger is fixed to the shaft.

  According to the twenty-third aspect, it is possible to obtain an image forming apparatus in which the manufacturing cost is reduced as compared with the case of using a conveyance device in which the middle part of the coil auger is fixed to the shaft.

1 is a schematic diagram illustrating an overall configuration of an image forming apparatus according to a first embodiment. It is a side view which shows the powder conveying apparatus of 1st embodiment. It is an enlarged view which shows the confluence | merging part of the powder conveying apparatus of 1st embodiment. It is sectional drawing which shows the principal part of the powder conveying apparatus of 1st embodiment. It is sectional drawing which shows the principal part of the powder conveying apparatus which concerns on 2nd embodiment. It is sectional drawing which shows the principal part of the powder conveying apparatus which concerns on 3rd embodiment. It is sectional drawing which shows the principal part of the powder conveying apparatus which concerns on 4th embodiment. It is sectional drawing which shows the principal part of the powder conveying apparatus which concerns on 5th embodiment. It is sectional drawing which shows the principal part of the powder conveying apparatus which concerns on 6th embodiment. It is a cross-sectional view which shows the principal part of the powder conveying apparatus which concerns on 6th embodiment. It is a cross-sectional view which shows the principal part of the powder conveying apparatus which concerns on 7th embodiment. The

(First embodiment)
Hereinafter, a first embodiment of the present invention will be described with reference to the drawings. First, the overall configuration and operation of the image forming apparatus 10 according to the present embodiment will be described with reference to FIG. Next, the powder conveyance device 100 will be described with reference to FIG. An arrow H shown in the drawing indicates a device height direction, and an arrow W indicates a device width direction. An arrow D indicates a device depth direction orthogonal to each of the device height direction H and the device width direction W.

<< Overall configuration of image forming apparatus >>
As shown in FIG. 1, the image forming apparatus 10 includes an image forming unit 8 and a control device 24.

[Image forming unit]
The image forming unit 8 includes a medium storage unit 12, a toner image forming unit 14, a transport unit 16, a fixing device 18, and a discharge unit 20. The image forming unit 8 forms an image on the recording medium P. The control device 24 controls the operation of each unit of the image forming apparatus 10.

[Toner image forming section]
The toner image forming unit 14 includes image forming units 40Y, 40M, 40C, and 40K, and a transfer unit 50. Here, yellow (Y), magenta (M), cyan (C) and black (K) are examples of toner colors constituting the powder. The transfer unit 50 is an example of a transfer device.

  The configuration is substantially the same except for the toner used in the image forming units 40Y, 40M, 40C, and 40K. In FIG. 1, the reference numerals of the respective parts constituting the image forming units 40M, 40C, 40K are omitted. Further, in the following description, the subscripts of the image forming units 40Y, 40M, 40C, and 40K and the members constituting them are omitted when it is not necessary to distinguish the colors.

<Image forming unit>
The image forming unit 40Y includes a photoreceptor 42Y, a charging device 44Y, an exposure device 60Y, and a developing device 46Y. Although the reference numerals are omitted in the drawing, the image forming units 40M, 40C, and 40K are provided with the photosensitive members 42M, 42C, and 42K, the charging devices 44M, 44C, and 44K, and the exposure devices 60M, 60C, and 60K so as to correspond to the respective colors. And developing devices 46M, 46C, and 46K.

(Photoconductor)
The photoconductor 42 has a function of holding a toner image developed by the developing device 46 while rotating around its own axis. A blade 47 is in contact with the photoconductor 42 and scrapes and collects the residual toner remaining on the photoconductor 42.

(Charging device)
The charging device 44 has a function of charging the photoreceptor 42.

(Exposure equipment)
The exposure device 60 has a function of forming a latent image on the charged photoreceptor 42.

(Developer)
The developing device 46 has a function of developing the latent image formed on the photoreceptor 42 as a toner image.

<Transfer unit>
The transfer unit 50 has a function of secondarily transferring the toner image to the recording medium P after the toner image of each color developed on each photoconductor 42 is primarily transferred. The transfer unit 50 includes a transfer belt 52, a plurality of primary transfer rolls 54, a drive roll 56, and a secondary transfer roll 58.

  A blade 59 is in contact with the transfer belt 52, and the waste toner remaining on the transfer belt 52 is scraped and collected.

[Transport section and discharge section]
The transport unit 16 has a function of transporting the recording medium P stored in the medium storage unit 12 through the transport path 16 </ b> C to the discharge unit 20. The transport unit 16 includes a delivery roll 16A and a plurality of transport roll pairs 16B.

[Fixing device]
The fixing device 18 has a function of fixing the toner image secondarily transferred to the recording medium P to the recording medium P by applying pressure while heating.

<Operation of Image Forming Apparatus>
Next, the operation of the image forming apparatus 10 will be described with reference to FIG.

  An image signal transmitted from an external device (PC as an example) is converted into image data of each color by the control device 24 and output to each exposure device 60.

  Subsequently, the exposure light emitted from each exposure device 60 is incident on each photoconductor 42 charged by each charging device 44 to form a latent image. Subsequently, each latent image is developed as a toner image of each color by each developing device 46. Subsequently, the toner images of the respective colors are primarily transferred to the transfer belt 52 by the respective primary transfer rolls 54.

  On the other hand, the recording medium P is conveyed and secondarily transferred in accordance with the timing at which the portion of the transfer belt 52 where the toner image is primarily transferred reaches the nip T.

  Subsequently, the recording medium P onto which the toner image has been secondarily transferred is conveyed toward the fixing device 18, and the toner image is fixed to the recording medium P.

  Then, the recording medium P on which the toner image is fixed is discharged to the discharge unit 20, and the image forming operation is completed.

[Powder conveying device]
FIG. 2 is a diagram showing the powder conveying device. Waste toner collected from the photosensitive member 42 and the transfer belt 52 by the blades 47 and 59 is collected in the powder conveying device 100 and collected by the powder conveying device 100. Sent to the bottle 102.

  The powder conveying apparatus 100 is an apparatus that conveys toner as powder, and includes a T-shaped fixing bracket 104. The powder conveying apparatus 100 includes a main conveying path 106 having a long conveying path and an auxiliary conveying path 108 that is obliquely connected to the main conveying path 106 and has a short conveying path. Hollow coil augers 110 and 112 each formed in a spiral shape are accommodated in the conveyance path 108. The coil augers 110 and 112 are formed by bending a wire rod in a spiral shape and have a hollow structure that does not have a shaft portion at the center of the rotation axis.

  The main transport path 106 is configured by connecting a plurality of cylindrical metal pipes, which will be described later, and a plurality of cylindrical resin pipes in a straight line. The inner diameters of the metal pipes and the resin pipes are substantially the same. The dimensions are the same. A first coil auger 110 is accommodated in the main conveyance path 106, and the toner in the main conveyance path 106 is sent from the upstream side to the downstream side by the rotation of the first coil auger 110.

  The sub-transport path 108 is configured by a pair of cylindrical resin pipes described later, and the inner diameter dimensions of both resin pipes are substantially the same. As shown in FIG. 3, a second coil auger 112 that feeds toner to the main transport path 106 side by rotational movement is accommodated in the sub-transport path 108, and the second coil auger 112 is from the first coil auger 110. short.

  A subordinate concept of the metal constituting each metal pipe described later is aluminum, and the metal pipe is composed of an aluminum pipe that is a general-purpose part. As a result, procurement costs are reduced. Moreover, the resin pipe mentioned later is formed with the synthetic resin.

  Each of the coil augers 110 and 112 is composed of metal linear members 110A and 112A bent into a spiral coil shape, and stainless is given as a subordinate concept of the metal constituting the linear members 110A and 112A. It is done.

(Main transport path)
The main conveyance path 106 will be described in detail. As shown in FIG. 2, the main conveyance path 106 is inclined obliquely, and the front end portion that is the downstream side in the conveyance direction is constituted by the first resin pipe 114. From the front end portion and the rear end portion of the first resin pipe 114, a fixing piece 114A extends laterally, and the fixing piece 114A is fixed to the housing by screws or the like.

  The front end of the first resin pipe 114 is closed by a front end side rotation member 116, and is fixed to the front end side rotation member 116 in a state where the front end portion of the first coil auger 110 is fitted. A rotation gear 116 </ b> B that is rotated by a rotation mechanism (not shown) is fixed to the shaft portion 116 </ b> A that extends from the front end side rotation member 116. By rotating the front end side rotation member 116 by the rotation mechanism and rotating the first coil auger 110 in the main conveyance path 106, the toner in the main conveyance path 106 is conveyed from the upstream side to the downstream side.

  An outlet 118 that opens downward in the installed state is provided at a portion of the peripheral surface (side surface) of the first resin pipe 114 located on the rear end side from the front end side rotating member 116. It is connected to the collection bottle 102.

  A large diameter portion 114B having a larger diameter than the general portion is formed at the rear end portion of the first resin pipe 114, and the front end portion of the first metal pipe 120 is fitted in the large diameter portion 114B. It is fixed. The first metal pipe 120 has a rear end connected to the second resin pipe 122.

  As shown in FIG. 3, a large diameter portion 122A is formed at the front end portion and the rear end portion of the second resin pipe 122, and the rear end portion of the first metal pipe 120 is the large diameter portion 122A on the front end side. It is fixed in a state of being fitted inside. From each large-diameter portion 122A, a fixing piece 122B extends laterally, and the fixing piece 122B is fixed to the fixing bracket 104 by a screw 124.

  The peripheral surface of the second resin pipe 122 is provided with a downstream merging port 122C that opens upward in the installed state, and the downstream merging port 122C is recovered by one of the blades 47 and 59. Waste toner is supplied. The front end portion of the third resin pipe 126 is fixed in the large diameter portion 122A on the rear end side of the second resin pipe 122.

  A large diameter portion 126A is formed at the rear end portion of the third resin pipe 126, and a fixing piece 126B extending from the side surface and the large diameter portion 126A to the side is formed on the third resin pipe 126. Yes. The fixing piece 126B extending from the side surface is fixed to the fixing bracket 104 by screws 124, and the fixing piece 126B extending from the large diameter portion 126A is positioned by a pin 104A provided on the fixing bracket 104.

  An upstream junction 126 </ b> C that opens upward in the installed state is provided on the peripheral surface of the third resin pipe 126. The upstream junction 126 </ b> C feeds toner from the sub-transport path 108 to the main transport path 106. A merging portion 128 is formed to be merged. The front end portion of the second metal pipe 130 is fixed in the large diameter portion 126 </ b> A of the third resin pipe 126.

  Thus, the main transport path 106 includes the first metal pipe 120 and the second metal pipe 130, and the length dimension of the first metal pipe 120 is longer than that of the second metal pipe 130. As shown in FIG. 2, the rear end portion of the second metal pipe 130 is fixed in a state of being fitted into a large diameter portion 132 </ b> A formed on the front end side of the fourth resin pipe 132.

  In the fourth resin pipe 132, a fixing piece 132B extends laterally from the side surface of the rear end portion and the large diameter portion 132A, and the fixing piece 132B is fixed to the fixing bracket 104 by screws 124. An inlet 132C opened upward in the installed state is provided on the peripheral surface of the fourth resin pipe 132, and waste toner or carrier collected by any of the blades 47 and 59 is supplied from the inlet 132C. Is done.

  The rear end of the fourth resin pipe 132 is closed by a rear end side rotating member 134 that is rotatably accommodated, and the rear end portion of the first coil auger 110 is fitted to the rear end side rotating member 134. It is fixed in the state. Thus, a continuous first coil auger 110 is provided between the front end side rotation member 116 and the rear end side rotation member 134.

(Sub transport path)
As shown in FIG. 3, the sub-transport path 108 is inclined with respect to the main transport path 106, and the sub-transport path 108 is located upstream of the main transport path 106 toward the downstream side where the toner is transported. Inclined to the side.

  The sub-transport path 108 is configured by a supply pipe 136 having a resin pipe on the rear end side that is the upstream side. The rear end of the supply pipe 136 is closed by a rotating member 138 that is rotatably accommodated. The rotating member 138 is fixed in a state in which the rear end portion of the second coil auger 112 is fitted, and the front end of the second coil auger 112 is a free end.

  The rotating member 138 is connected to the rotating gear 140 via a bevel gear (not shown). The rotation gear 140 is rotated by a rotation mechanism (not shown) and the second coil auger 112 is rotated in the sub-transport path 108, so that the toner in the sub-transport path 108 is transported from the upstream side to the downstream side to the main transport path 106. send.

  A fixed piece 136 </ b> A extends laterally from the supply pipe 136, and the fixed piece 136 </ b> A is fixed to the fixed bracket 104 with a screw 124. A supply port 142 is provided on the peripheral surface of the supply pipe 136, and waste toner collected by one of the blades 47 and 59 is supplied from the supply port 142.

  The supply pipe 136 is provided with a vibration generating unit 144 that vibrates the portion of the second coil auger 112 corresponding to the supply port 142 toward the supply port 142 as the second coil auger 112 rotates. The vibration generating unit 144 includes a conveyance path-side protrusion 146 that protrudes from the inner peripheral surface 136 </ b> B of the supply pipe 136 constituting the sub-conveyance path 108 toward the second coil auger 112.

  The conveyance path side protrusion 146 is formed in a triangular plate shape, and has a height at which the top portion constituting the tip is disposed between the spirally wound linear members 112 </ b> A constituting the second coil auger 112. Yes. The conveyance path side protrusion 146 is formed at a location on the inner peripheral surface 136 </ b> B that faces the supply port 142. As a result, the spiral linear member 112 </ b> A constituting the second coil auger 112 hits the transport path-side protrusion 146 and gets over the transport path-side protrusion 146 when rotating. At this time, the portion of the second coil auger 112 that has interfered with the conveyance path side protrusion 146 is elastically deformed toward the supply port 142 and vibrates.

  The front end portion of the supply pipe 136 is fixed in a state of being fitted in the large-diameter portion 148A of the relay pipe 148, and the relay pipe 148 is formed of a resin pipe.

  From the relay pipe 148, a fixed piece 148B extends to the side, and the fixed piece 148B is fixed to the fixed bracket 104 by a screw 124. The opening at the front end of the relay pipe 148 communicates with the upstream junction 126 </ b> C of the third resin pipe 126, and the toner from the sub conveyance path 108 is merged with the main conveyance path 106.

(First coil auger)
As shown in FIG. 4, the main conveyance path 106 includes a first region 150 having a small gap SM between the inner circumferential surface 106 </ b> A and the outermost peripheral portion of the first coil auger 110, and a gap SM smaller than the first region 150. The second region 152 having a large height is formed. The first region 150 and the second region 152 are alternately formed in the length direction NH, which is the direction in which the main transport path 106 extends (see FIG. 2).

  All portions of the first coil auger 110 disposed in the metal pipes 120 and 130 constituting the main transport path 106 are small diameter portions 110B having a smaller outer diameter dimension G than other portions. As a result, the first coil auger 110 is formed with a small diameter portion 110B and a large diameter portion 110C larger in diameter than the small diameter portion 110B, and the first region 150 and the second region in the main conveyance path 106 having a constant inner diameter. 152 are formed.

As for the site | part of the 1st coil auger 110 arrange | positioned in the 1st metal pipe 120 and the 2nd metal pipe 130, the whole region is made into the small diameter part 110B. Further, the changed portion 154 of the outer diameter G of the first coil auger 110 coincides with the boundary KK between each metal pipe 120, 130 and each resin pipe 114, 122, 126, 132. Here, when the inner diameter of the metal pipes 120, 130 or the resin pipes 114, 122, 126, 132 changes at the connecting portion, the boundary KK is a region where the inner diameter dimension changes halfway.
Thereby, the site | part of the 1st coil auger 110 arrange | positioned in each resin pipe 114,122,126,132 of each metal pipe 120,130 is made into the large diameter part 110C larger diameter than the small diameter part 110B. Yes.

  The first resin pipe 114 that constitutes one of the resin pipes 114 and 122 on both sides of the first metal pipe 120 is provided with a powder toner outlet 118 on the side surface as shown in FIG. ing. The portion of the first coil auger 110 corresponding to the outlet 118 is a large diameter portion 110C having a larger diameter than the small diameter portion 110B.

(Action / Effect)
The effect | action of this embodiment which concerns on the above structure is demonstrated.

  A gap SM between the inner peripheral surface 106 </ b> A of the main conveyance path 106 and the first coil auger 110 is larger than the first region 150 in the second region 152 disposed in each of the metal pipes 120 and 130. Thereby, interference with the metal 1st coil auger 110 and the metal pipes 120 and 130 by bending is suppressed, and generation | occurrence | production of abnormal noise is suppressed.

  For this reason, in order to suppress the contact with the metal pipe due to the bending of the metal coil auger, the manufacturing cost can be reduced as compared with the case where the shaft is passed through the center of the coil auger and the middle part is fixed to the shaft. it can.

  At this time, the toner conveying ability by the first coil auger 110 is highly dependent on the moving speed in the length direction NH of the mountain shape formed by the linear member 110A formed in a spiral shape. Further, there is no shaft or the like for supporting the first coil auger 110 in the main transport path 106. For this reason, since the toner can be transported using the inner and outer paths of the linear member 110A formed in a spiral shape, abnormal noise can be prevented without significantly reducing the toner transport capability.

  Further, the second region 152 was formed by providing a small-diameter portion 110B having a smaller outer diameter G than other portions at the portion of the first coil auger 110 disposed in the metal pipes 120 and 130.

  For this reason, compared with the case where metal pipe 120,130 is made large diameter and the 2nd field 152 is formed, the level | step difference which may arise in the connection part with the edge part of metal pipe 120,130 can be suppressed.

  The small diameter portion 110B can be formed by adjustment during processing. For this reason, it is possible to take measures against abnormal noise without increasing the cost.

  Furthermore, the entire region of the first coil auger 110 disposed in the metal pipes 120 and 130 is a small diameter portion 110B.

  For this reason, the interference with the metal pipes 120 and 130 of the first coil auger 110 is suppressed as compared with the case where a part of the metal pipes 120 and 130 is the small diameter portion 110B.

  The main conveyance path 106 includes a plurality of metal pipes 120 and 130, and small diameter portions 110 </ b> B are provided in all of the portions of the first coil auger 110 disposed in the metal pipes 120 and 130.

  Thereby, in all the metal pipes 120 and 130, interference with the 1st coil auger 110 and the metal pipes 120 and 130 is suppressed.

  And at least one part of the site | part of the 1st coil auger 110 arrange | positioned in each resin pipe 114,122,126,132 is made into the large diameter part 110C larger diameter than the small diameter part 110B.

  For this reason, the center line of the first coil auger 110 is mainly conveyed compared to the case where all the portions of the first coil auger 110 arranged in the resin pipes 114, 122, 126, 132 are the small diameter portions 110B. It can be close to the center line of the path 106.

  At this time, the portion of the first coil auger 110 disposed in the resin pipes 114, 122, 126, 132 on both sides of the metal pipes 120, 130 has a larger diameter than the small diameter portion 110B.

  For this reason, the center line of the first coil auger 110 is set to the main conveyance path 106 as compared with the case where the portion of the first coil auger 110 arranged in the resin pipes 114, 122, 126, 132 is the small diameter portion 110B. It can be close to the center line. Thereby, interference of the 1st coil auger 110 to the metal pipes 120 and 130 adjacent to this resin pipe 114,122,126,132 can be suppressed.

  The first resin pipe 114, which is one of the resin pipes 114 and 122 on both sides of the first metal pipe 120, is provided with a powder toner outlet 118 on the side surface, and at least a first coil auger corresponding to the outlet 118. 110 part is made larger diameter than the small diameter part 110B.

  For this reason, as compared with the case where the portion of the first coil auger 110 corresponding to the outlet 118 is the small diameter portion 110B, clogging of toner, which is powder in the vicinity of the outlet 118, is suppressed.

  Further, the third resin pipe 126 has a joining portion 128 formed on the side surface for receiving and joining the toner that is powder from the sub-conveying path 108, and the portion of the first coil auger 110 corresponding to the joining portion 128 is The large-diameter portion 110C is larger than the small-diameter portion 110B.

For this reason, compared with the case where the part of the 1st coil auger 110 corresponding to the confluence | merging part 128 is made into the small diameter part 110B, the clogging of the powder in the confluence | merging part 128 can be suppressed.
Similarly, clogging of powder at the downstream junction 122 </ b> C provided in the second resin pipe 122 can be suppressed.

  The powder conveying apparatus 100 includes a resin supply pipe 136 having a supply port 142 through which toner as powder is supplied. The supply pipe 136 includes a vibration generation unit 144 that vibrates a portion of the second coil auger 112 corresponding to the supply port 142 toward the supply port 142 as the second coil auger 112 rotates.

  For this reason, as compared with the case where the vibration generating unit 144 that vibrates the second coil auger 112 is not provided, the clogging of the toner that is powder in the vicinity of the supply port 142 can be suppressed by vibration.

  Accordingly, it is not necessary to separately prepare a breaking member for breaking the toner clogged in the vicinity of the supply port 142, so that the cost can be reduced and the addition of a drive source or the like becomes unnecessary. Further, only the first coil auger 110 can be provided in the main transfer path 106, and the cross-sectional area of the transfer path is not blocked. The vibration generating unit 144 is provided in the resin supply pipe 136, and there is less concern about abnormal noise compared to the case where the toner clogging is eliminated by applying vibration.

  The vibration generating unit 144 protrudes from the inner peripheral surface 106 </ b> A of the main conveyance path 106 toward the first coil auger 110 and is disposed between the helically wound linear members 110 </ b> A constituting the first coil auger 110. The conveyance path side protrusion 146 is configured.

  Therefore, the first coil auger 110 can be processed more easily than when the first coil auger 110 is processed to form the protrusions.

  By providing such a powder conveyance device 100, an image forming apparatus 10 with a reduced manufacturing cost can be obtained as compared with a case where a conveyance device in which the middle part of the first coil auger 110 is fixed to the shaft is used. be able to.

  In addition, in this embodiment, although the site | part of the 1st coil auger 110 arrange | positioned in the 1st metal pipe 120 and the 2nd metal pipe 130 was made into the small diameter part 110B over the whole region, it is not limited to this. For example, a part of the first coil auger 110 disposed in each of the metal pipes 120 and 130 may be the small diameter portion 110B.

  In this case, compared with the case where the whole area of the 1st coil auger 110 arrange | positioned in each metal pipe 120,130 is made into the small diameter part 110B, a conveyance capability can be improved.

  Moreover, although the small diameter part 110B was provided in all the site | parts of the 1st coil auger 110 arrange | positioned in each metal pipe 120,130, it is not limited to this. For example, you may provide the small diameter part 110B in the site | part of the 1st coil auger 110 arrange | positioned in one part metal pipe 120,130.

  In this case, the shape of the first coil auger 110 can be simplified as compared with the case where all the portions of the first coil auger 110 arranged in the metal pipes 120 and 130 are the small diameter portions 110B. .

  At this time, among the metal pipes 120 and 130 constituting the main transport path 106, the first coil auger 110 disposed in the first metal pipe 120 having the longest length dimension in the transport direction of the toner as powder is provided. The small diameter part 110B is set.

  In this case, as compared with the case where the small diameter portion 110B is set at the site of the first coil auger 110 arranged in the short second metal pipe 130, the metal pipe 130 is not loosened due to the slack of the first coil auger 110. Interference suppression effect increases.

(Second embodiment)
FIG. 5 is a diagram illustrating the main conveyance path 106 according to the second embodiment. The same or equivalent parts as those in the first embodiment are denoted by the same reference numerals, and description thereof is omitted, and only different parts are described. . This embodiment differs in the shape of the 1st coil auger 110 compared with 1st embodiment.

  That is, the first coil auger 110 according to the present embodiment is provided with a small diameter portion 110B and a large diameter portion 110C having a larger diameter than the small diameter portion 110B at a portion disposed in the first metal pipe 120.

  Accordingly, the main conveyance path 106 includes a first region 150 in which the gap SM between the inner peripheral surface 106 </ b> A and the outermost peripheral portion of the first coil auger 110 is small, and a second region in which the gap SM is larger than the first region 150. Are formed in the first metal pipe 120.

  The small diameter portion 110B is provided at the center C portion of the first metal pipe 120 in the length direction NH.

  Also in the present embodiment having the above-described configuration, it is possible to obtain the same effects as those of the first embodiment.

  Further, compared with the case where the inside of the first metal pipe 120 is configured only by the small diameter portion 110B, the conveying ability of the toner as powder can be enhanced.

  And this small diameter part 110B is provided in the center C part of the length direction NH of the 1st metal pipe 120. As shown in FIG. For this reason, compared with the case where the center C part of the length direction NH of the 1st metal pipe 120 is made into the large diameter part 110C, to the 1st metal pipe 120 of the 1st coil auger 110 resulting from the slack of the center part Interference can be suppressed.

(Third embodiment)
FIG. 6 is a cross-sectional view showing the main conveyance path 106 according to the third embodiment. The same or equivalent parts as those in the first embodiment are denoted by the same reference numerals and the description thereof is omitted, and only different parts are explained. To do. This embodiment differs in the shape of the 1st coil auger 110 compared with 1st embodiment.

  That is, the first coil auger 110 according to the present embodiment is provided with a small diameter portion 110B and a large diameter portion 110C having a larger diameter than the small diameter portion 110B at a portion disposed in the first metal pipe 120. The changed portion 154 of the outer diameter G of the first coil auger 110 is set to the rear end side from the center C in the length direction NH of the first metal pipe 120, and the small diameter portion 110 B is formed on the first metal pipe 120. It is arranged at the center C part in the length direction NH.

  The small diameter portion 110B is formed up to the front end of the first coil auger 110, and the changed portion 154 of the outer diameter dimension G is a single location.

  Also in the present embodiment having the above-described configuration, it is possible to obtain the same effects as those of the first embodiment.

  Further, compared with the case where the inside of the first metal pipe 120 is configured only by the small diameter portion 110B, the conveying ability of the toner as powder can be enhanced.

  Furthermore, since the small diameter portion 110B is formed up to the front end of the first coil auger 110, and the changed portion 154 of the outer diameter dimension G is one place, a plurality of changed portions 154 where the outer diameter dimension G is changed are set. Compared to the case, the first coil auger 110 can be easily manufactured.

(Fourth embodiment)
FIG. 7 is a view showing a powder conveyance device 100 according to the fourth embodiment, and a view corresponding to FIG. 4 of the first embodiment is shown. In the present embodiment, the same or equivalent parts as those in the first embodiment are denoted by the same reference numerals and description thereof is omitted, and only different parts are described. This embodiment differs in the shape of the 1st coil auger 110 compared with 1st embodiment.

  That is, in the first coil auger 110 according to the present embodiment, the changed portion 154 of the outer diameter dimension G coincides with the boundary KK between the first metal pipe 120 and the second resin pipe 122.

  The small diameter portion 110B is formed up to the front end of the first coil auger 110, and the changed portion 154 of the outer diameter dimension G is a single location. Thereby, the site | part of the 1st coil auger 110 corresponding to the confluence | merging part 128 of the 3rd resin pipe 126 is made into the large diameter part 110C larger diameter than the small diameter part 110B.

  Also in the present embodiment having the above-described configuration, it is possible to obtain the same effects as those of the first embodiment.

  Moreover, compared with the case where the changed portion 154 where the outer diameter dimension G is changed does not coincide with the boundary KK between the first metal pipe 120 and the second resin pipe 122, the first metal pipe 120 of the first coil auger 110 is moved to. Interference is suppressed.

  Further, the portion of the first coil auger 110 corresponding to the merge portion 128 of the third resin pipe 126 is a large diameter portion 110C having a larger diameter than the small diameter portion 110B. For this reason, as compared with the case where the portion of the first coil auger 110 corresponding to the merging portion 128 is the small diameter portion 110B, clogging of toner that is powder in the merging portion 128 can be suppressed.

(Fifth embodiment)
FIG. 8 is a cross-sectional view showing a part of the main conveyance path 106 according to the fifth embodiment. The same or equivalent parts as those in the first embodiment are denoted by the same reference numerals and the description thereof is omitted and different parts. Only will be described. This embodiment differs in the 1st metal pipe 120 compared with 1st embodiment.

  That is, in the first metal pipe 120 according to the present embodiment, the inner diameter dimension I1 is larger than the inner diameter dimension I2 of each of the resin pipes 114, 122, 126, 132 constituting the other part of the main transport path 106. As a result, a second region 152 in which the gap SM between the inner peripheral surface 106 </ b> A of the main conveyance path 106 and the outermost peripheral portion of the first coil auger 110 is larger than the first region 150 is formed.

  Also in the present embodiment having the above-described configuration, it is possible to obtain the same effects as those of the first embodiment.

  In the present embodiment, the first coil auger 110 can be easily manufactured as compared with a case where a part of the first coil auger 110 has a small diameter.

(Sixth embodiment)
FIG. 9 and FIG. 10 are views showing a powder conveyance device 100 according to the sixth embodiment, and a view corresponding to FIG. 4 of the first embodiment is shown. In the present embodiment, the same or equivalent parts as those in the first embodiment are denoted by the same reference numerals and description thereof is omitted, and only different parts are described. This embodiment differs in the shape of the supply pipe 136 compared with 1st embodiment.

  That is, the vibration generating unit 144 provided in the supply pipe 136 is configured by the first conveyance path side protrusion 146A and the second conveyance path side protrusion 146B that are provided apart from each other in the length direction NH of the second coil auger 112. Yes. An interval K2 in the length direction NH between the first conveyance path side protrusion 146A and the second conveyance path side protrusion 146B is a dimension that is a non-integer multiple of the winding pitch MP of the linear member 112A wound in a spiral shape.

  Further, the first transport path side protrusion 146A and the second transport path side protrusion 146B are provided at positions shifted in the circumferential direction S on the inner peripheral surface 136B of the supply pipe 136, as shown in FIG. Accordingly, the first transport path side protrusion 146A and the second transport path side provided at different positions in the length direction NH depending on the mold inserted from the front end side of the supply pipe 136 and the mold inserted from the rear end side. The protrusion 146B can be formed.

  Also in the present embodiment having the above-described configuration, it is possible to obtain the same effects as those of the first embodiment.

  Further, the distance K2 in the length direction NH between the first conveyance path side protrusion 146A and the second conveyance path side protrusion 146B is a dimension that is a non-integer multiple of the winding pitch MP of the linear member 112A wound in a spiral shape. Yes. Thereby, when the second coil auger 112 is rotated, the timing at which the spiral linear member 112A gets over the first conveyance path side protrusion 146A and the timing at which the spiral linear member 112A gets over the second conveyance path side protrusion 146B can be shifted.

  Thereby, the second coil auger 112 can be expanded and contracted between the adjacent conveyance path side protrusions 146A and 146B with rotation. Thereby, the second coil auger 112 can be vibrated in the length direction NH.

(Seventh embodiment)
FIG. 11 is a cross-sectional view showing the sub-transport path 108 according to the seventh embodiment. The same or equivalent parts as those in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted, and only different parts are shown. explain. This embodiment differs in the shape of the 2nd coil auger 112 compared with 1st embodiment.

  That is, the second coil auger 112 is provided with a coil side protrusion 160 at a position corresponding to the supply port 142, and the coil side protrusion 160 protrudes to the side (radially outward) from the second coil auger 112. . A vibration generator 144 is formed on the second coil auger 112 by the coil-side protrusion 160.

  Also in the present embodiment having the above-described configuration, it is possible to obtain the same effects as those of the first embodiment.

  Further, even when the second coil auger 112 in the supply pipe 136 is disposed below the inner peripheral surface 136B by its own weight as shown in FIG. Is positioned on the lower side, the second coil auger 112 can be pushed up to the supply port 142 side to vibrate. Thereby, the toner clogged in the vicinity of the supply port 142 can be broken by the second coil auger 112.

  Therefore, the molding cost of the supply pipe 136 can be reduced as compared with the case where the vibration generating portion 144 is formed by processing the supply pipe 136.

  In each embodiment, the case where a part of the main conveyance path 106 is configured by the metal pipes 120 and 130 has been described, but the present invention is not limited to this. For example, the entire main conveyance path 106 may be formed of a metal pipe. In this case, the gap between the first coil auger 110 and the inner peripheral surface of the metal pipe is configured to be small at the end portion in the extending direction of the main conveyance path 106 and large at the center portion. Suppresses abnormal noise caused by interference. Thereby, compared with the case where the middle part of the 1st coil auger 110 is fixed to an axis | shaft, the powder conveying apparatus 100 which suppressed manufacturing cost can be obtained.

8 Image forming unit 10 Image forming apparatus 100 Powder conveying device 106 Main conveying path 106A Inner peripheral surface 108 Sub conveying path 110 First coil auger 110A Linear member 110B Small diameter part 110C Large diameter part 112 Second coil auger 112A Linear member 114 First resin pipe 118 Outlet 120 First metal pipe 122 Second resin pipe 122C Downstream side junction 126 Third resin pipe 126C Upstream side junction 128 Junction 130 Second metal pipe 132 Fourth resin pipe 132C Inlet 136 Supply pipe 142 Supply port 144 Vibration generating portion 146 Conveyance path side protrusion 146A Conveyance path side protrusion 146A First transport path side protrusion 146B Second transport path side protrusion 150 150 First area 152 Second area 154 Change location 160 Coil side protrusion C Center G Outside diameter I1 Inner Diameter I2 Inner Diameter K2 Interval

Claims (23)

A powder conveying path constituted by connecting a metal pipe and a resin pipe in a straight line; and
It is formed in a spiral shape that rotates in the conveyance path and conveys powder, and a gap between the inner circumferential surface of the conveyance path and a second area that is larger than the first area in the extending direction of the conveyance path is A series of coil augers formed in a metal pipe;
A powder conveying device.   The powder conveying apparatus according to claim 1, wherein an inner diameter of the metal pipe forming the conveying path is made larger than other portions of the conveying path to form the second region.   The powder conveying apparatus according to claim 1, wherein the second region is formed by providing a small-diameter portion having an outer diameter smaller than that of the other portion at a portion of the coil auger disposed in the metal pipe.   The powder conveying apparatus according to claim 3, wherein the entire area of the coil auger portion disposed in the metal pipe is the small diameter portion.   5. The powder according to claim 3, wherein the conveyance path includes a plurality of the metal pipes, and the small-diameter portion is provided in all of the portions of the coil auger disposed in each metal pipe. Body transport device.   The resin pipes are provided at both ends of the metal pipe, and the portions of the coil auger disposed in the resin pipes on both sides of the metal pipe have a larger diameter than the small diameter part. The powder conveying apparatus as described in any one of Claims 5.   One of the resin pipes on both sides of the metal pipe has a powder outlet on a side surface, and at least a portion of the coil auger corresponding to the outlet has a larger diameter than the small diameter portion. Item 7. The powder conveying apparatus according to Item 6.   The powder conveying apparatus according to claim 3, wherein at least a part of the coil auger disposed in the metal pipe is the small diameter portion.   The powder conveyance device according to claim 8, wherein the conveyance path includes a plurality of the metal pipes, and the small-diameter portion is provided at a portion of the coil auger arranged in a part of the metal pipes.   The powder conveyance device according to claim 9, wherein the small diameter portion is set at a portion of the coil auger arranged in the metal pipe having the longest length in the powder conveyance direction among the plurality of metal pipes.   The powder conveyance device according to any one of claims 8 to 10, wherein the small-diameter portion and a portion having a larger diameter than the small-diameter portion are provided at a portion of the coil auger disposed in the metal pipe. .   The powder conveying apparatus according to claim 11, wherein the small diameter portion is provided at a central portion in a length direction of the metal pipe.   The powder conveyance device according to any one of claims 3 to 12, wherein at least a part of a portion of the coil auger disposed in the resin pipe has a larger diameter than the small diameter portion.   At least a part of the resin pipe has a joining portion that accepts and joins powders from the other on the side surface, and a portion of the coil auger corresponding to the joining portion has a larger diameter than the small diameter portion. The powder conveying apparatus according to claim 13.   The powder conveying apparatus according to any one of claims 3 to 5, wherein the small-diameter portion is formed up to an end of the coil auger, and an outer diameter change portion is a single location.   The powder transfer device according to claim 15, wherein the changed portion is disposed at a boundary between the metal pipe and the resin pipe.   The powder according to claim 15 or 16, wherein the resin pipe is provided with a merging portion that merges with other portions, and a portion of the coil auger corresponding to the merging portion has a larger diameter than the small diameter portion. Body transport device.   A vibration generating unit that includes a supply pipe made of a resin having an opening in which a supply port for supplying powder is opened, and vibrates a portion of the coil auger corresponding to the supply port toward the supply port as the coil auger rotates. The powder conveying apparatus as described in any one of Claims 1-17 provided with.   The powder conveyance device according to claim 18, wherein the vibration generating unit is configured by a coil side protrusion that protrudes laterally from the coil auger.   The vibration generating portion is configured by a conveyance path-side protrusion that protrudes from the inner peripheral surface of the conveyance path toward the coil auger and is disposed between the spirally wound linear members that constitute the coil auger. The powder conveying apparatus according to claim 18 or 19.   A plurality of the conveyance path side protrusions are provided in the length direction of the coil auger, and the interval between the adjacent conveyance path side protrusions is a non-integer multiple of the winding pitch of the linear member wound spirally. The powder conveying apparatus according to claim 20. A conveying path in which a part of the conveying path of the powder is constituted by a metal pipe;
A coil auger that is formed in a spiral shape that rotates in the conveyance path and conveys powder, and a gap with the inner peripheral surface of the metal pipe is small at the end in the extending direction of the conveyance path and large at the center,
A powder conveying device. An image forming unit that forms an image on a recording medium using toner;
The powder conveying apparatus according to any one of claims 1 to 22, wherein the toner is conveyed as powder.
An image forming apparatus comprising: