JP2008185856A - Toner conveying device and image forming apparatus with the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a toner conveying device improving toner conveying force while simplifying an image forming apparatus. <P>SOLUTION: The toner conveying device 30 built in the image forming apparatus 1 comprises: a pipe 36 for conveying the toner through the inside thereof; a plurality of screws 42 which are arranged in the pipe, and connected in series from one end of the pipe to the other end to transmit rotation, thereby conveying the toner in the pipe; and a driving part 32 which is connected to the screws at the end part of the pipe and rotatively drives the screws. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a toner conveying device suitable for being incorporated in an image forming apparatus typified by a copying machine, a printer, a facsimile, and the like, and an image forming apparatus equipped with the toner conveying device.

In this type of image forming apparatus, a toner image is formed on an image carrier, for example, a photosensitive drum, and this image is transferred and fixed on a sheet.
On the other hand, toner remains on the drum. For this reason, a technique is known in which the toner is collected by a cleaning device and collected in a collection container through a pipe of the toner conveying device (see, for example, Patent Documents 1 and 2).

  Specifically, in the technique of Patent Document 1, air is sent into a pipe, and toner in the pipe is conveyed using air pressure. On the other hand, in the technique of Patent Document 2, a coil member is provided in a pipe, and toner in the pipe is conveyed by vibration of the coil member.

Japanese Patent Laid-Open No. 10-333521 JP 2001-222196 A

However, the technique disclosed in Patent Document 1 has a problem that the image forming apparatus becomes complicated and the apparatus cannot be simplified. This is because various means for controlling the gas flow rate and the like are required.
On the other hand, in the technique of Patent Document 2 described above, since a coil member is used, a large torque cannot be transmitted in the pipe, and in particular, the toner conveyance force becomes the smallest in the central portion of the pipe and the toner remains in the pipe. It becomes easy. For example, when the image forming apparatus is installed in a high humidity environment, there is a problem that the toner aggregates (blocks) in the pipe and the fluidity of the toner deteriorates.

  SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a toner conveying device capable of obtaining a strong toner conveying force while eliminating the above-mentioned problems and achieving simplification of the image forming device, and an image forming device equipped with the toner conveying device. That is.

  A first invention for achieving the above object is a toner conveying device incorporated in an image forming apparatus, wherein a plurality of pipes in which toner is conveyed and a plurality of pipes are arranged in the pipe, from one end of the pipe. A screw that conveys the toner in the pipe and is connected to the screw at the end of the pipe, and a drive unit that drives the screw to rotate by being connected in series across the other end to transmit the rotation. .

According to the first invention, a plurality of screws are disposed in the pipe, these screws are connected in series from one end to the other end of the pipe, and each screw is driven to rotate in the pipe. Therefore, a larger torque can be transmitted in the pipe than in the conventional case, and the toner in the pipe is reliably conveyed by the screw. As a result, even if the toner is aggregated in the pipe, a strong conveying force can be obtained, so that blocking can be eliminated.
Further, since various means for controlling the gas flow rate and the like as in the prior art are not necessary, it is possible to achieve simplification of the image forming apparatus incorporating the toner conveying device.

According to a second aspect of the present invention, in the configuration of the first aspect, the pipe includes a cylindrical portion in which each screw is disposed, and a joint portion that connects the cylindrical portions and can change the axial direction of the cylindrical portion. It is characterized by that.
According to 2nd invention, in addition to the effect | action of 1st invention, the pipe which equips it with the screw further is comprised as a flexible bendable pipe. Therefore, it is possible to freely set the path for conveying the toner, and the degree of freedom of the apparatus layout of the image forming apparatus incorporating the toner conveying apparatus is increased.
In addition, since the pipe is composed of a cylindrical portion and a joint portion on which the screw is arranged, the pipe and the screw can be used for other types of image forming apparatuses. It also contributes to the reduction of manufacturing costs.

According to a third invention, in the configuration of the second invention, the screw is formed at a shaft disposed along the axis of the cylindrical portion, a blade standing in a spiral manner on the shaft, and both ends of the shaft. A coupling for connecting the screw, the coupling having a ball formed at one end of the shaft and a cap formed at the other end of the shaft to receive the ball of the other shaft, A first screw angle restricting portion that surrounds a joint portion between the ball and the end of the shaft and allows the shaft to precess, and an axis. It has a second screw angle restricting portion that is formed along the direction and allows the arm portion to swing.
According to the third invention, in addition to the action of the second invention, the coupling is composed of a ball and a cap, and the cap can allow the precession of the shaft and the swinging of the arm, respectively. A screw angle restricting portion is provided. Therefore, this screw can fully correspond to a flexible bendable pipe, and the degree of freedom of device layout is further increased.

According to a fourth aspect of the invention, in the configuration of the third aspect of the invention, the blade has an interference preventing portion that is formed to have a smaller diameter than the maximum outer diameter portion in the vicinity of the ball or in the vicinity of the cap.
According to the fourth invention, in addition to the action of the third invention, the blade has the interference preventing portion in the vicinity of the ball or the cap, and the screws are not arranged in a straight line in the pipe. Even in this case, since the contact between the blades of the adjacent screws is avoided, the durability of the toner conveying device is improved.

According to a fifth aspect of the present invention, in the configuration of the first to fourth aspects, the toner conveying device includes a cleaning device that recovers toner remaining on the image carrier, and a toner recovery container that is disposed at the bottom of the image forming device. It is characterized by being arranged between.
According to the fifth invention, in addition to the effects of the first to fourth inventions, a sufficient conveying force can be obtained even when there is a long distance between the cleaning device and the collection container.

The sixth invention is characterized in that the toner conveying device according to the first to fifth inventions is mounted, and the toner on one end side of the pipe is conveyed toward the other end side of the pipe using this.
According to the sixth aspect, in addition to the simplification of the image forming apparatus according to the first to fifth aspects and the high degree of freedom of the layout, the toner can be quickly conveyed. Is immediately performed, which contributes to improving the reliability of the image forming apparatus.

  According to the present invention, it is possible to provide a toner conveying apparatus that obtains a strong toner conveying force while achieving simplification of the image forming apparatus, and an image forming apparatus equipped with the toner conveying apparatus.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 schematically shows the structure of a multifunction machine 1 that is an example of an image forming apparatus. Note that arrows indicated by solid lines in the drawing indicate a sheet conveyance path and its conveyance direction.

  As shown in the figure, a cassette type paper feed unit 4 is disposed at the lower part of the main body 2 of the multifunction machine 1. This paper feed unit 4 is provided with four stages of paper feed cassettes 6 along the height direction of the main body 2, and each cassette 6 is located on the front side with respect to the main body 2 (front side as viewed in FIG. 1). ) Can be pulled out toward Each cassette 6 stores sheets P before image formation in a stacked state, and these sheets are separated one by one from the sheet feeding unit 4 and sent to the right.

A paper transport unit 8 is disposed on the right side of the paper feed unit 4, and the paper delivered from the paper feed unit 4 is transported upward along the right side surface of the main body 2. Next, the sheet is reversed toward the left side in the main body 2 and is conveyed toward the left side as it is.
Inside the main body 2, a registration roller 10, a print engine 14, and a transfer unit 20 are sequentially arranged on the downstream side in the paper conveyance direction from the conveyance unit 8. An optical unit 12 is provided above the engine 14, and laser light is emitted from the optical unit 12 toward the photosensitive drum (image carrier) 16 of the engine 14.

Further, a fixing unit 22 and a discharge / branch unit 24 are sequentially arranged on the downstream side of the transfer unit 20 when viewed in the sheet conveyance direction. In the case of single-sided printing, the sheet discharged from the fixing unit 22 is discharged / branch unit. Then, the sheet is discharged to the sheet receiving tray 26.
On the other hand, a duplex printing unit 28 is disposed between the discharge / branch unit 24 and the paper supply unit 4, and the unit 28 conveys the paper discharged from the fixing unit 22 toward the paper transport unit 8. This sheet is sent to the engine 14 again.

  Here, the engine 14 is provided with a developing device 18 and a cleaning device 19, and toner is supplied to the developing device 18 from a toner supply device (not shown), and a toner image is formed on the drum 16. On the other hand, after transfer onto the paper P, toner remains on the drum 16. The remaining toner is collected by the cleaning device 19 and collected in a toner collection container 34 disposed at the bottom of the multifunction machine 1 via the toner conveying device 30 as shown in FIG.

  More specifically, the toner conveying device 30 of this embodiment includes a resin or rubber pipe 36, which connects the cleaning device 19 and the recovery container 34, and recovers from the drum 16 inside thereof. The transferred toner is conveyed. As shown in FIGS. 3 and 4 showing only a part of the toner conveying device 30, the pipe 36 includes four cylindrical portions 38 and four joint portions 40 that connect the cylindrical portions 38. The axial direction of the cylindrical part 38 located in the both ends can change the seam part 40 of a present Example by changing suitably the cylindrical bus-line length. 3 and 4, a part of the pipe 36 is cut for convenience of explanation.

  Further, a resin screw 42 is disposed in each cylindrical portion 38. Each screw 42 is connected in series in the pipe 36 and is disposed from one end of the pipe 36 connected to the cleaning device 19 to the other end of the pipe 36 in the vicinity of the recovery container 34. The other end is provided with a drive unit 32 (FIG. 2), which is connected to a screw 42 located at the other end, and the drive unit 32 rotationally drives all the screws 42 in the pipe 36. Thereby, the toner in the pipe 36 is conveyed toward the collection container 34. The driving unit 32 may be provided on the one end side of the pipe 36.

The screw 42 of this embodiment has a shaft 44. The shaft 44 is disposed along the axis of the tubular portion 38, and as shown in FIG. 5, a rigid spiral blade 46 is erected on the shaft 44. The outer diameter portion has at least one turn or more.
In addition, a coupling 50 is formed at both ends of the shaft 44 to connect the screw 42. On the blade 46, an interference preventing portion 48 is formed in the vicinity of the coupling 50, which is larger than the maximum outer diameter portion. It is configured with a small diameter by providing an additional angle.

The coupling 50 of this embodiment has a ball 52 formed at one end of the shaft 44 and a cap 58 formed at the other end of the shaft 44, and the cap 58 is a shaft 44 of the adjacent screw 42. The ball 52 formed in the above is received.
Specifically, for convenience of explanation, the ball 52 includes a spherical portion 54 as shown in FIG. 6 in which the cap 58 is cut along a substantially vertical direction and in FIG. 7 in which the cap 58 is cut along a substantially horizontal direction. The spherical surface portion 54 has an arm portion 56 extending in a direction orthogonal to the axis of the shaft 44, and the arm portion 56 is a cap 58 for receiving the ball 52, in other words, The rotation from the drive unit 32 is transmitted to the adjacent screw 42.

On the other hand, the cap 58 is configured as a universal shaft joint, and as shown in FIGS. 6 and 7, the cap 58 has a concave surface portion 60 for fitting the spherical surface portion 54 so as to be rotatable. The concave surface portion 60 is a screw. The angle restricting portions 62 and 64 communicate with the outer peripheral surface of the cap 58.
More specifically, the cap 58 of the present embodiment is provided with mortar-shaped first screw angle restricting portions 62, 62, and this angle restricting portion 62 is a joint portion between the ball 52 and the end of the shaft 44. It is formed in a go. Thereby, the angle restricting portion 62 has a function of preventing the ball 52 from coming off after the ball 52 is fitted to the cap 58 and allows the shaft 44 to precess.

After the screw 42 is disposed in the pipe 36, the pipe 36 is fixed, and the rotating shaft 44 cannot swing so as to draw a circle. However, the angle restricting portion 62 is formed to allow the precession of the shaft 44 so as to achieve the arrangement of the screw 42 that is not in a straight line.
On the other hand, a groove-shaped receiving portion 64 is formed in the cap 58 along the axial direction, and this receiving portion 64 is configured as a second screw angle restricting portion, and the arm portion 56 swings with respect to the rotation center of the ball 52. Allow movement. That is, the receiving portion 64 allows the arm portion 56 to move along the axial direction of the shaft 44. Note that the angle of the shaft 44 of the adjacent screw 42 depends on the smaller one of the screw angle restricting portions 62 and 64.

By the way, in this embodiment, in these adjacent screws 42, the blades 46 in the vicinity of the cap 58 and the blades 46 in the vicinity of the ball 52 received by the cap 58 have their standing positions continuous or overlapped. It is formed (FIGS. 6 and 7).
In the toner conveying device 30 described above, a screw 42 connected in series in the pipe 36 is incorporated, and one end of the pipe 36 is connected to the cleaning device 19, while the pipe 36 is freely routed in the main body 2. The other end of 36 is connected to the drive unit 32 and the collection container 34.

In the multi-function device 1 in which the toner conveying device 30 is incorporated, the paper P is separated and sent one by one from the cassette 6, and the paper P reaches the registration roller 10 through the paper conveying unit 8. The roller 10 feeds the paper P to the transfer unit 20 while correcting the oblique feeding of the paper P and timing the toner image formed by the print engine 14.
Further, based on image data from a controller (not shown), the multifunction device 1 controls the irradiation of the laser beam by the optical unit 12. As a result, an electrostatic latent image of the original image is created on the drum 16 in the engine 14, and then a toner image is formed on the drum 16 from the latent image and transferred to the paper P.

Thereafter, the sheet P is fed toward the fixing unit 22 with an unfixed toner image carried thereon, and the toner image is fixed by the heat roller at the fixing unit 22. Next, the paper P discharged from the fixing unit 22 is discharged to the tray 26 through the discharge / branch unit 24.
When double-sided printing is performed on this single-sided printing, the paper P discharged from the fixing unit 22 is pulled back to the unit 28 immediately before being discharged to the tray 26, and the paper P joins the paper transport unit 8. Then, it is sent again toward the transfer unit 20. In this case, the toner image is transferred to the surface of the paper P that has not been printed.

  Subsequently, the toner remaining on the drum 16 is collected by the cleaning device 19, and then the toner collected in the pipe 36 is collected in the collection container 34 by the rotation of the driving unit 32.

As described above, according to the present embodiment, a plurality of screws 42 are disposed in the pipe 36, and these screws 42 are connected in series from one end to the other end of the pipe 36. Are driven to rotate in the pipe 36. Therefore, a larger torque can be transmitted in the pipe 36 than in the conventional case, and the toner conveying force is not reduced even in the central portion of the pipe 36, and the toner in the pipe 36 can be reliably conveyed to the container 34 by the screw 42. It becomes. As a result, even if the toner is aggregated in the pipe 36, a strong conveying force can be obtained, so that blocking is easily eliminated.
Further, since various means for controlling the gas flow rate and the like are not required as in the prior art, it is possible to achieve simplification of the multifunction machine 1 incorporating the toner conveying device 30.

Furthermore, the pipe 36 provided with the screw 42 inside has a joint portion 40 for changing the axial direction of each cylindrical portion 38, and is configured as a flexible and bendable pipe. Therefore, a route for conveying the toner can be freely set, and the degree of freedom of the device layout of the multifunction machine 1 incorporating the toner conveying device 30 is increased.
In addition, the pipe 36 includes a cylindrical portion 38 on which the screw 42 is arranged and a joint portion 40. Since the pipe 36 and the screw 42 can be used for other types of multi-function machines, the parts can be shared. It also contributes to the reduction of the manufacturing cost of the multifunction machine.

  Furthermore, the coupling 50 is composed of a ball 52 and a cap 58. The cap 58 is provided with screw angle restricting portions 62 and 64 that can allow the precession of the shaft 44 and the swing of the arm portion 56, respectively. ing. Therefore, the screw 42 can sufficiently correspond to a flexible and bendable pipe, and the degree of freedom of device layout is further increased.

Further, the blade 46 has an interference preventing portion 48 in the vicinity of the ball 52, and even when the screws 42 are not arranged in a straight line in the pipe 36, the blades of adjacent screws 42 are not in contact with each other. As a result, the durability of the toner conveying device 30 is improved.
Further, when viewed with these adjacent screws 42, the spiral trajectories are continuous or overlapped, so that it becomes difficult for the toner to stay in the pipe 36, and the toner can be efficiently conveyed.

Furthermore, even when there is a long distance between the cleaning device 19 and the collection container 34, the toner conveying device 30 described above provides a sufficient conveying force.
In addition, if the above-described toner transport device 30 is installed in the multi-function device 1, the multi-function device 1 can be simplified and the degree of freedom in layout can be increased, and the toner can be transported quickly. This can be implemented immediately and contributes to improving the reliability of the multifunction device 1.
The present invention is not limited to the above embodiment, and various modifications can be made without departing from the scope of the claims.

  For example, in the above embodiment, the interference preventing portion 48 is formed in the vicinity of the ball 52, but it may be formed in the vicinity of the cap 58 as shown in FIG. In the above embodiment, the arm portion 56 and the receiving portion 64 are arranged in the same orthogonal direction with respect to the shaft 44. However, as shown in the figure, the arm portion 56 and the receiving portion 64 are orthogonal to each other. In these cases as well, in the same way as described above, the apparatus can be simplified and a strong toner conveying force can be obtained.

  Further, as in the above embodiment, the ball 52 is formed at one end of the shaft 44, the cap 58 is formed at the other end of the shaft, the cap is formed at one end of the shaft 44, and the ball is formed at the other end of the shaft. May be. Furthermore, the lengths of the shafts 44 may be formed to have the same length or different lengths. Further, the material of the pipe 36 and the screw 42 is not limited to the above embodiment.

  Further, in the above-described embodiment, the toner transport device 30 is disposed between the cleaning device 19 and the collection container 34. However, the toner transport device of the present invention can be used at a location where toner can be transported, for example, the cleaning device 19. And the developing device 18 or between the toner replenishing device and the developing device 18. Also in this case, the toner can be reused or the toner supply amount can be made uniform immediately, which contributes to the improvement of the reliability of the multifunction device 1.

  Finally, in the above-described embodiment, an example in which the image forming apparatus is embodied in a multifunction machine is shown. However, the image forming apparatus of the present invention can naturally be applied to a copying machine, a printer, a facsimile, a scanner, and the like.

1 is a schematic configuration diagram of a multifunction machine according to an embodiment. FIG. 2 is a schematic configuration diagram of the multifunction machine viewed from the back of FIG. 1. FIG. 3 is a partial cross-sectional perspective view of the toner conveyance device surrounded by III in FIG. 2. FIG. 4 is a plan view, a front view, and a side view of FIG. 3. It is the front view and AA arrow directional cross-sectional view of the screw of FIG. It is explanatory drawing of the coupling of FIG. It is explanatory drawing of the coupling of FIG. It is the front view and BB arrow sectional drawing of the screw in another Example.

Explanation of symbols

1 MFP (image forming device)
16 Photosensitive drum (image carrier)
DESCRIPTION OF SYMBOLS 19 Cleaning apparatus 30 Toner conveyance apparatus 32 Drive part 34 Recovery container 36 Pipe 38 Cylindrical part 40 Seam part 42 Screw 44 Shaft 46 Blade | wing 48 Interference prevention part 50 Coupling 52 Ball | bowl 56 Arm part 58 Cap 62 1st screw angle control part 64 Receiving part (second screw angle regulating part)

Claims (6)

A toner conveying device incorporated in an image forming apparatus,
A pipe through which toner is conveyed,
A plurality of screws disposed in the pipe, connected in series from one end to the other end of the pipe and transmitted to transmit rotation, thereby conveying a toner in the pipe;
A toner conveying device, comprising: a drive unit coupled to the screw at an end of the pipe and configured to rotationally drive the screw. The toner conveying device according to claim 1,
The pipe is
A cylindrical portion in which the screws are disposed;
A toner conveying device comprising: a connecting portion that connects the cylindrical portions and is capable of changing an axial direction of the cylindrical portions. The toner conveying device according to claim 2,
The screw is
An axis disposed along the axis of the cylindrical portion;
A blade standing in a spiral on the shaft;
A coupling that is formed at both ends of the shaft and connects the screw;
The coupling is
A ball formed at one end of the shaft, and a cap formed at the other end of the shaft to receive the ball of the other shaft;
The ball has an arm that transmits rotation to a cap to be received;
The cap is formed along a first screw angle restricting portion that surrounds a joint portion between the ball and the end portion of the shaft and allows the precession of the shaft, and the arm. A toner conveying device having a second screw angle restricting portion that allows the portion to swing. The toner conveying device according to claim 3,
The toner conveying device according to claim 1, wherein the blade includes an interference preventing portion that is formed to have a smaller diameter than the maximum outer diameter portion in the vicinity of the ball or the cap. The toner conveying device according to claim 1,
The toner conveying device is disposed between a cleaning device for collecting toner remaining on the image carrier and a toner collecting container disposed at the bottom of the image forming apparatus. apparatus. An image forming apparatus comprising: the toner conveying device according to claim 1, wherein the toner on one end side of the pipe is conveyed toward the other end side of the pipe using the toner conveying device. apparatus.

Images