JPS62260173A - Copying machine or printing press - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a radiation-based, non-contact type fuser for treating and fixing toner acid on copy sheets.
The present invention relates to devices and, more particularly, to an anti-toner contamination control for a radiant user device to prevent toner contamination of the operating components of the user device.

BACKGROUND OF THE INVENTION In electrophotographic copying and printing machines, an electrostatic latent image is formed on a photoreceptor and developed.

The developed image is then transferred to a suitable copy substrate, such as a copy sheet. The device sheet carrying the unprocessed toner image is transported to a user device where the toner is fused and fused to form a permanent copy.

A radiant non-contact type user device includes a heat source,
It includes an oven-like chamber with a heat reflective/transfer surface to concentrate heat and melt the toner as the copy sheet passes through the user device. In this type of user device, there is usually no contact between the toner image and the heated components of the user device. Despite this, toner has been found to accumulate on user surfaces, particularly on the heated/reflective surfaces of user devices. Because of the relatively high temperatures of the internal fuser process, the toner burns, at least initially, creating fumes on the affected fuser surfaces. If magnetic toner is used,
Opaque dust is generated when organic materials are burned. As a result of this, the energy transferred from the fuser charge to the substrate to fuse the toner is reduced. Also, over time, the amount of toner on the user surface accumulates to the point that a cluster or pile of small protrusions of toner is formed. Once the Jfi M+ of these toners reaches a significant amount, they can be used on copy sheets and user
They can adhere to or rub against the unprocessed toner image, disturbing, scraping, and distorting the final image. Additionally, molten toner from these deposits can touch and adhere to the copy sheet, creating undesirable marks on the finished copy.

OBJECTS AND SUMMARY OF THE INVENTION The present invention seeks to solve the above-mentioned problems by facilitating toner smear prevention control for copiers and printing machines, which includes a base, a forcing surface and a a housing facing the base forming a heat reflecting surface facing the base for reflecting heat; a radiant heat source disposed within the housing; and a copying substrate in contact with the heat source. to prevent, or at least to the maximum extent prevent, the tendency of the copy substrate to migrate toward the heating surface of the radiant non-contact user device of the copying machine, having a shield for shielding the copying machine from The copy substrate is passed between the housing and the base during user processing such that heat from a heat source melts the toner on the copy substrate and the housing of the user device is passed between the housing and the base. , biased at position r,
Apparatus is provided for neutralizing the tendency of toner from the copy substrate to migrate to the forcing surfaces and shields of the user device housing.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIG. 1 of the drawings, there is shown an automatic electrophotographic copying machine, generally designated 10, which incorporates the toner loss prevention control of the present invention.

The copying machine 1o shown in FIG. The i~lunar follow-up control in the user device of the present invention is the copying machine 1.
It is particularly suitable to use with 0, but from the following explanation, it can be equally preferably applied to various forms of copying b1 and printing I, and is limited to application 1 shown here. It must be obvious that there is no need to do so.

Reproduction 1ff10 has an image recording photoreceptor 15 in the form of a drum, the outer circumferential surface of which has a suitable photoconductive material 16. The photoreceptor 15 is suitably rotatably pivoted within a machine frame (not shown) by a shirt 17.

A main drive motor 19 is drivingly connected to the front first receptacle 15;
is rotated in the direction indicated by arrow 18 to pass light 41 side 16 of photoreceptor 15 to a series of electrophotographic processing stations. A suitable controller 21 having a microprocessor 22 and memory 23 is provided to operate the various components making up the copier 10 under predetermined time relationships and to copy the original document 14, such as a copy sheet 20. It is designed to be copied onto a final support sheet. For those who are proficient in this technique,
Memory 23 is a suitable read-only memory (ROM)
, random access memory (RAM), and/or non-volatile memory (NVM), such memory 23 may contain various operating parameters for copying 1110 and programming by the user or operator of the copier. It functions to store the operation information of the copying machine.

First, the optical 5ffi surface 16 of the photorecharger 15 is uniformly charged by a suitable charging device such as a scorotron 25 at a charging station 24. This uniformly charged photoreceptor light 61 and 16 is transmitted to the exposure station 26.
to form an electrostatic latent image of the original document 14 on the photoreceptor 15-1. To this end, a suitable support surface or platen 28 for the original document 14 is provided, which has a negative passing scanning aperture or slit 30. A suitable document transport device, shown here by a pair of constant speed inlet and outlet rollers 32,33, is provided for moving the original document 1 through the scanning slit 30. The roll pairs 32 , 33 are drivingly connected to the main drive motor 19 , and the roll pairs 32 are connected to an electromagnetically actuated clutch 34 .
are connected via. A suitable document sensor 31 is provided at the entrance to the platen 28 to detect the insertion of a document to be reproduced and to initiate operation of the copier 10.

A lamp 35 arranged below the platen 28 serves to illuminate the scanning slit 30 and its linear portion of the original dogmen 1-14 located above it. A suitable fiber optic lens array 37, constructed, for example, from a gradient index fiber element, is provided to direct the image beam reflected from the linear portion of the original document being scanned into the image beam at the exposure station 26. 1~
The light 4 of the resetter 15 is transmitted to the electricity 16.

After exposure, the electrostatic latent image on photoconductive surface 16 of photoreceptor 15 is developed at development station 4o. At development station 40, a suitable development device, such as a magnetic brush roll 41 mechanically coupled to a main drive motor, converts a suitable developer mix in developer housing 43 into an electrostatic latent image. The electrostatic latent image is developed into a visible image.

Copy sheets 20 are supported in a stack on a tray base 44 of a copy sheet supply I/ray 45. Suitable suppression means are provided to raise the tray base 44 of toner 45 and bring the uppermost sheet of the stack 47 of copy sheets 2o into operative relationship with the segment feed roll 49. The feed roll 49 is driven by the main drive motor 19 via an electromagnetically actuated clutch 51 . roll 49
is operated by actuation of clutch 51 to feed the uppermost copy sheet toward the nip of a pair of registration rolls 50, which transfer the copy sheet to photoreceptor 1.
5 to the image of the photoconductive surface 16. Matching roll vs. 5o
advances the copy sheet to transfer station 52. At this transfer station, transfer/Butatuku Corotron 53
．． A suitable transfer/deck device, such as at 54, brings the copy sheet into transfer relationship with the developed image on photoconductive surface 16, and also brings the copy sheet into transfer relationship with the developed image on photoconductive surface 16 for image fixation and ejection as the final copy. Then peel it off.

Following the transfer station 52, the image carried on the copy sheet is conveyed to a radiant non-contact user device 57.
The image is permanently fixed to the copy sheet in the user equipment. Following user processing, the finished copies are conveyed by roll pair 56 to a suitable receptacle, such as a pick-up tray (not shown). Registration roll pair 50 and transport roll pair 56 are driven by main drive motor 19 via suitable drives such as belts and pulleys.

After transfer, residual toner remains on the photoconductive surface 16 of the F'AI-receiver 15 and is removed by a cleaning blade 63 at a cleaning station 62. The toner removed by the member 63 is collected by a suitable collector 64.
It is gathered inside and taken out.

Although a drum-type photoreceptor has been shown and described, it will be appreciated that other types of photoreceptors can be used, such as belts, webs, and the like.

Referring specifically to FIG. 2, the fuser device 57 includes an upper fuser assembly 70 and a lower fuser assembly 71. The assemblies 70, 71 are suitably supported in fixed position relationship within the machine frame. User assembly 70
．． Preferably, the overall width dimension of 71 is the same as or slightly greater than the width of the largest copy sheet to be processed.

The lower user assembly 71 has a copy seat support base 75 that supports the user during user processing.
It forms a flat support 76 on which the copy sheet 20 rests as it passes through the device 57. To limit the temperature of this support base 76, the interior 78 of the support base 75 is hollow through which air can flow.

The body 76 of the base 75 is preferably overcoated with a suitable black absorbent overcoating material 79 to allow rapid warming of the base 75.

The underside or underside 180 of the upper fuser assembly 70 is flat and has forced surfaces 81 at the inlet and outlet of the fuser device 57.
and 82 are formed. The forcing surfaces 81,82 serve to constrain the copy sheet 20 as it enters, passes through, and exits the user device. The forcing surfaces 81,82 may be provided with suitable heat reflective coatings or coverings to improve user handling. In the central portion of the wall 80 there is a lower fuser assembly 7.
An inwardly curved semicircular quadrant 83 facing 1 is formed. A suitable heat source, in the form of a six-arrow lamp 85, is provided within this section 83, extending across the width of the user device and suitably supported on opposite sides of the assembly 70. ing. The curved surface 86 of the quadrant 83 is relatively smooth and coated with a suitable heat reflective coating or covering 88 to reflect and concentrate the heat radiated from the lamp 85 towards the base 75. is preferable. Lower fuser assembly 7
In case 1, the interior of the upper fuser assembly 70 is hollow to allow cooling air to flow therethrough. Fin-like protrusions 92 on the interior 93 of the wall 81 further improve cooling performance. A transparent shield 95 covers the opening of recess 83 to prevent the possibility of user-processed copy sheets coming into contact with hot lamp 85 and extruding.

Upper fuser assembly 70 and lower fuser assembly 7
1 are positioned at predetermined positions relative to each other so as to form a slit-shaped opening 1oO of predetermined dimensions through which the copy sheet 20 supporting the fused toner images 1 to 1 can pass unhindered. arranged in relationship.

Radiant fuser devices, such as fuser device 57, often experience toner smearing problems, which typically occur as toner folds up surface 81 and/or shield 95. As toner build-up increases, the user
It increases the density and mass above 81 and 95 which are used as devices.

Since the temperature of the shield 95 of the user equipment F1 is relatively high,! -M, which consists of na, burns and remains as a slight pierce. When magnetic toner is used, after the organic toner is vaporized due to high fuser processing temperatures, typical dust particles are deposited on the shield 9 of the fuser device.
5 remain on top. Any build-up of dirt or dust on the fuser shield will impede energy flow from lamp 85 to the unfused copy sheet, reducing fuser processing efficiency and flexibility.

In addition, local concentrations and clamps of toner occur, which form "stalactite"-like protrusions that grow downwards into the path to the copy sheet 1. This rm stalactite-like protrusion is formed on the surface 81 on the upstream side near the shield 95 of the fuser device.
Attach to and grow downward. These toner growths sweep across the unfused toner image of the moving copy sheet, disturbing and distorting the unfused toner image. When the molten toner from these formations contacts the copy sheet, it adheres and forms an undesirable mark on the copy sheet.

The foregoing chips and dust contamination on user device passageways such as surface 81 of upper user assembly 70 and/or shield 95 are susceptible to electrostatic repulsion, such as charged toner powder on a copy sheet. As a result, it is believed that the contamination of these toner powders on the upper fuser assembly 70 is due to electrostatic forces. Also, this Mc 16
It is believed that the extent to which this occurs is a result of the copy sheet contacting a portion of the upper user assembly 70 as the copy sheet passes through the user device 57.

To eliminate the tendency for unfused toner to migrate from copy sheet 20 to upper user-assembly 70,
An electrical bias is applied to the upper today assembly. For this purpose, a power supply 105 of an appropriate potential is provided, and this power supply 105 has the same electrode as the electrode of the band of unmelted residual (i.e., post-transfer) toner on the copy sheet. are doing. Line 106 is D. C. A power supply 105 is electrically connected to the upper user assembly 70. The D, C, lf source 105 is of sufficient height to prevent the transfer of charged toner powder to the upper user assembly, particularly the fuser 81 and the shield 95, while at the same time A bias potential is provided so as not to disturb the unfused toner, ie, the movement of the copy sheet into, through, and out of the user device 57.

In the illustrated and described user device 57, the shield 9
5 is made of non-conductive material. However, the bias provided to upper user assembly 70, including section 83, serves to prevent migration of shield 95 and surface 81 toner from the copy sheet. Alternatively, the shield 95 can be made electrically conductive, for example by using a conductive coating thereon. In this case, the bias applied to the upper user assembly 70 applied to the shield itself prevents any toner from migrating to the shield.

Although the user device 57 has been shown and described with a shield 95, it will be appreciated that the shield can be omitted.

In one embodiment, photoreceptor 16 is corotron 2
5 to about +750 volts <B (q).

The magnetic toner used had a truly negative charge.

A bias of about -250 volts applied to the upper fuser assembly alpha body 70 has been found to effectively prevent toner from transferring or adhering to the upper fuser assembly.

The present invention prevents and obstructs the transfer of t) to the components of the fuser device, and prevents the formation of straw and/or gunk on the shield of the fuser device or the upper fuser assembly. Toner and "stalactites" on the strong υ1 side 81
Prevents build-up of developer. As a result of this, the processing efficiency, performance and! The reduction in the degree of freedom of one's abilities is greatly reduced.

Although the invention has been described with respect to the configurations shown herein, it is not intended to be limited to the details described above, but on the contrary, it covers such variations and modifications as fall within the scope of the claims. This is clearly illustrated.

[Brief explanation of drawings]

FIG. 1 is a side view of an electrophotographic copying machine or print of a type adapted to incorporate toner smear prevention controls in a user device of the present invention. FIG. 2 is an enlarged view showing the configuration of a user device of a copying machine and details of toner stain prevention control in the user device of the present invention. 10... Copy machine 14... Original document 15... Photoreceptor 19... Drive motor 20... Copy sheet 21... Controller 24... Charging station 26... Exposure station 40... - Development station 52... Transfer station 57... Non-contact user device 70.71... User assembly 75... Base 81.82... Forced surface 86... Reflective surface 95...・Seal 105・D, C, Ti source

Claims (1)

Claims: A movable photoreceptor, an apparatus for charging a photoreceptor in preparation for imaging, an apparatus for exposing a charged photoreceptor to form an electrostatic latent image on the photoreceptor, an electrostatic latent image A copying machine or a printing machine having a device for developing a photoreceptor, a device for transferring the developed image onto a copy substrate at a transfer station, and a conveying device for bringing the copy substrate into transfer relationship with a photoreceptor at the transfer station. a) a fuser device for fusing a toner image transferred to the copy substrate to form a permanent copy, the fuser device having opposed first and second fuser assemblies; The copy substrate is passed between the fuser assemblies during fusing, and the first fuser assembly includes: (a) a radiant heat source; and (b) a reflector disposed near the heat source. wherein the heat source and the reflector cooperate with the second fuser assembly to define a fuser treatment area through which the substrate passes during fusing. , a reflector having a heat-reflecting inner surface for reflecting heat from the heat source and concentrating it on the copy substrate when the copy substrate passes through the fuser processing area; (c) the copy substrate; at least one forcing surface for restraining the copy substrate as it is being fused; b) the transport device transports the substrate from the transfer station and through the fuser device; c) D. the first fuser assembly to prevent toner from the substrate from transferring to the forced surface of the first fuser assembly as the substrate passes through the fuser device; C. A copying machine or a printing machine, comprising: a device for applying an electrical bias with a potential; and a copying machine or printing machine.