CN101320238B - Electrifying device, process cartridge and image forming apparatus - Google Patents

Electrifying device, process cartridge and image forming apparatus Download PDF

Info

Publication number
CN101320238B
CN101320238B CN2008101253026A CN200810125302A CN101320238B CN 101320238 B CN101320238 B CN 101320238B CN 2008101253026 A CN2008101253026 A CN 2008101253026A CN 200810125302 A CN200810125302 A CN 200810125302A CN 101320238 B CN101320238 B CN 101320238B
Authority
CN
China
Prior art keywords
charging
gap
mentioned
charging roller
holding part
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Fee Related
Application number
CN2008101253026A
Other languages
Chinese (zh)
Other versions
CN101320238A (en
Inventor
小菅明朗
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Ricoh Co Ltd
Original Assignee
Ricoh Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from JP2004296877A external-priority patent/JP4420784B2/en
Application filed by Ricoh Co Ltd filed Critical Ricoh Co Ltd
Publication of CN101320238A publication Critical patent/CN101320238A/en
Application granted granted Critical
Publication of CN101320238B publication Critical patent/CN101320238B/en
Expired - Fee Related legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Abstract

The invention relates to image forming devices such as a copier, a printer, a fax machine and a plotter, a charging unit used in the image forming devices and a manufacturing method for the charging unit, a processing cartridge and a setting method for charge gap. A charging roller 14 comprises a metal core 101 as a conductive support, a charging layer 102 made of conductive resin material, sheet-like gap holding component 103 provided between two ends of the charging layer 102. The gap holding component 103 is connected with a photosensitive layer 5b out of an image region 5a of a photoreceptor 5. Average value of the charging gaps when environmental temperature is 10 DEG C, 20 DEG C or 30 DEG C are respectively set as G10, G20, G30, satisfying the following condition: |G30-G10| X 5 is less than G20. Even in the event that a measurement device and a regulation device for the charging gaps are not provided, environmental variation of the charging gaps can still be reduced to realize high durability at low cost.

Description

Charging device, cartridge processing and image processing system
The application be that January 10, application number in 2005 are 200510003636.2 the applying date, denomination of invention divides an application for the patented claim of " charging device, cartridge processing and image processing system ".
Technical field
The present invention relates to duplicating machine, printer, facsimile recorder, image processing systems such as plotter, charging device that in above-mentioned image processing system, uses and manufacturing approach thereof, cartridge processing, the establishing method in charging gap.
Background technology
In the past, as the charging device of image processing system, main flow was charging modes such as grid-control charger unit; But there is the problem of discharge products such as a large amount of generation ozone in this mode, therefore; In recent years, the charging device of the way of contact that is widely used, its with roller or brush etc. as charging unit.
In the charging device of the way of contact, receive the charging unit electrostatic attraction as carrying the rubbish such as toner put on the body (photoreceptor), after operation between long-term, dirts such as toner are dirty to be caused charging bad, becomes the principal element that influences the charging device life-span.
In order to reduce the dirty dirty of charging roller (charging unit), open among the 2000-194868 (following brief note is " patent documentation 1 ") for example spy, the adhering and sealing parts at the charging roller both ends have been proposed, between photoreceptor and charging roller, form the method in small charging gap.
Open among the 2002-55508 (following brief note for " patent documentation 2 ") for example spy, proposed to be provided with in the charging roller end ladder or groove, the method for assemblage gap parts wherein is as the formation method in the charging gap of not using film-like members.
The general material of using elastomeric elements such as rubber or sponge as charging roller; Also can use resin material; This is that people are known, for example opens 2001-337515 (following brief note is " patent documentation 3 ") the spy, and the spy opens described in the 2003-66693 (following brief note is " patent documentation 4 ").
Open 2001-312121 (following brief note is " patent documentation 5 ") for example spy; The spy opens among the 2000-206805 (following brief note is " patent documentation 6 "), has proposed in the charging unit end roller to be set, and rubs between reduction and the photoreceptor; Form the method in charging gap; This occasion, configuration gap holding part part (roller) joins itself and the image-region of photoreceptor non-finish department (non-photographic layer) outward.
Open among the flat 8-339092 (following brief note is " patent documentation 7 ") for example spy; In order to improve the antifriction consumption or the physical strength of Organophotoreceptor; Proposed to make the inorganics microparticulate, perhaps opened among the flat 11-218945 (following brief note is " patent documentation 8 "), in order to improve lubricity for example spy; Proposed to make particulate fluorocarbon resin to disperse, to carry the method that forms protective seam on the surface of putting at picture.
Be in the mode of contactless state in that the relative photoreceptor of charging roller is set, compare, can reduce the dirty dirty of charging roller with the way of contact.
But because charging roller material relation, there is the upper limit in the charging gap between photoreceptor and the charging roller, if the charging gap greater than permissible value paradoxical discharge takes place then, it is irregular to produce concentration on the image, therefore, must precision keep the charging gap well.
Charging unit constitutes occasion by rubber, and hardness is along with temperature change is big, exists the charging gap to be subject to environmental impact and the problem that changes.
Countermeasure as the problems referred to above; Open 2002-108059 (following brief note is " patent documentation 9 ") for example spy; The spy opens among the 2002-139893 (following brief note is " patent documentation 10 "); Means and the adjustment means of measuring the charging gap have been proposed to be provided with, according to the method in environmental change adjustment charging gap.
In addition; About the gap occasion is set between charging roller and photoreceptor, the scope in above-mentioned gap is opened flat 7-301973 (following brief note is " patent documentation 11 ") for example spy; Among the Te Kaiping 8-202125 (following brief note is " patent documentation 12 "), record 30～240 μ m etc.
Open among the 2002-229307 (following brief note is " patent documentation 13 ") for example spy; Charging roller as non-contacting elastomeric element is disclosed; The gap is at circumferencial direction and axially have 10～40 μ m variation, to charging roller stack DC bias voltage and AC bias voltage, the AC bias voltage is carried out low-voltage control.
In addition; Open 2002-251055 (following brief note is " patent documentation 14 ") for example spy; Te Kaiping 8-184980 (following brief note is " patent documentation 15 "), spy open among the 2003-076101 (following brief note is " patent documentation 16 "), disclose the non-image areas use distance member at the charging roller two ends; Make picture carry and put the body non-contact charge, charging unit is to be the resistive layer of major component with the fluororesin; Metal oxide particle is dispersed in picture carries and to put the body protective seam, carry at picture and put the body protective seam and contain the fluorine-type resin particle; Can control of all kinds charged respectively.
Through configuration charging roller and photoreceptor noncontact, compare with contacting the configuration occasion, can reduce the dirty dirty of charging roller.But paradoxical discharge because there is the upper limit in charging roller material relation, if the charging gap surpasses permissible value, then can take place in the gap between charging roller and photoreceptor (following brief note is " charging gap "), and it is irregular to cause that concentration takes place on the image.
In addition, the charging gap varies in size, and suitable charging bias value is different, therefore; Even the charging gap is in the allowed band, if charging gap deviation is big, then in the place of charging room gap length; The charging bias voltage is not enough, and charging potential is low, in charging narrow place, gap; Discharge can become surplus, toner or adjuvant film forming take place on photoreceptor, or the photoreceptor abrasion increases.
Therefore, need make that not only the mean value in the charging gap between charging roller and the photoreceptor is suitable, and the deviation or the amplitude of fluctuation in charging gap need be in the suitable scope also.To this; In example in the past, though putting down in writing the allowed band (but charging interstice coverage of homogeneous charging) in the gap of charging and the mean value in charging gap, still; When charging roller and photoreceptor revolution, the amplitude of fluctuation in charging gap and charging gap deviation along its length etc. is not touched.
In addition, charging unit is the rubber occasion, realizes that through cut high-precision processing is difficult to, and hardness receives influence of temperature change big, exists along with the labile problem in environmental change charging gap.
On the other hand, resinous charging unit hardness is high, and cut is easy; Be prone to realize high-precision processing, still, because high rigidity; The thin parts that use film like are as gap holding part part occasion, and after during certain, abrasion can take place film-like members; Perhaps film adhesive is emerged from the end, and the undesirable condition that toner is cemented in the there takes place.
When using Organophotoreceptor as the photoreceptor occasion, at the linking part of film-like members, the photoreceptor damage takes place sometimes.
So; Being provided with in the mode of ladder or groove of above-mentioned patent documentation 2 records in the charging roller end; Through constitute for example gap holding part part with thick elastic body, can prevent the early stage deterioration of gap holding part part and photoreceptor connecting part, can also prevent that the gap holding part part breaks away from.Though improved permanance, gap holding part part thickness deviation influence charging gap changes, and exists the charging gap to change problem greatly.
6 records of above-mentioned patent documentation 5 and patent documentation make that non-photographic layer position outside the image-region of gap holding part part and photoreceptor joins mode in; Photographic layer can deterioration; But; In order to prevent the bias voltage leakage to the non-finish department of photoreceptor of charging, need between charging unit and gap holding part part, guarantee the abundant distance that does not take place to leak from the charging unit end.Therefore, the photoreceptor body tube must be grown, and there is the whole problem that maximizes of device in the result.
In the method that adjustment means in charging gap are set of above-mentioned patent documentation 9 and patent documentation 10 records, can adjust according to environmental change, still; Charging gap as target is tens μ m horizontal zones; In image processing system, measure and adjust the in fact very difficulty of gap of should charging, measure mechanism and adjusting mechanism requirement high precision; Constitute complicacy, have problems such as expensive.
Summary of the invention
The present invention puts forward for solving the existing problem of above-mentioned prior art; The objective of the invention is to; Even provide be not provided with the charging gap measure means and adjustment means also can make the charging gap receive environmental change influence little, can be with the charging device and the manufacturing approach thereof of implemented with low cost high-durability; Be provided with the cartridge processing of this charging device, image processing system, and the establishing method in charging gap.
Another object of the present invention is to; Provide can keep accurately the charging gap, again can reduce charging gap variation or deviation, minimizing charging roller dirty dirty prevent abnormal image, can be with the charging device and the manufacturing approach thereof of implemented with low cost high-durability; Be provided with the cartridge processing of this charging device; Image processing system, and the establishing method in charging gap.
To achieve these goals, the present invention proposes following scheme:
(1) a kind of charging device comprises charging unit, makes picture carry to put body charged with contactless state, it is characterized in that:
Through above-mentioned charging unit material condition is preestablished in deciding scope, through the change characteristic of this charging unit to environmental baseline itself, inhibition environmental baseline dynamic field closes and states the amplitude of fluctuation of putting the charging gap between body and the charging unit as carrying.
(2) in the charging device of above-mentioned (1); It is characterized in that above-mentioned environmental baseline is made as environment temperature, is benchmark with this environment temperature with the position, intermediate portion; Be set at upper limit side and lower limit side ladder; The mean value in above-mentioned charging gap when asking for each environment temperature is set above-mentioned charging unit material condition, the mean value the when multiple value of the absolute value of the difference of mean value is less than the middle part environment temperature when mean value and lower limit side ring border temperature when making upper limit side ring border temperature.
In the charging device of above-mentioned (2), it is characterized in that (3) above-mentioned charging unit has roll shape, the mean value in the above-mentioned charging gap when above-mentioned environment temperature is 10 ℃ is made as G 10, the mean value in the above-mentioned charging gap when environment temperature is 20 ℃ is made as G 20, the mean value in the above-mentioned charging gap when environment temperature is 30 ℃ is made as G 30, satisfy the following formula condition:
|G 30-G 10|×5＜G 20
In any charging device of above-mentioned (1)-(3), it is characterized in that (4) above-mentioned charging gap is in 15～90 mu m ranges.
In any charging device of above-mentioned (1)-(3), it is characterized in that (5) above-mentioned charging unit hardness is more than JIS D standard 50 degree.
In the charging device of above-mentioned (5), it is characterized in that (6) above-mentioned charging unit is made up of electroconductive resin.
(7) in any charging device of above-mentioned (1)-(6), it is characterized in that,, form the charging gap through sheet gap holding part part being set at above-mentioned charging unit both ends.
(8) in any charging device of above-mentioned (1)-(6), it is characterized in that, form stage portion at above-mentioned charging unit both ends, along this charging unit radially have a degree of depth, through the gap holding part part is located at this stage portion, form above-mentioned charging gap.
In the charging device of above-mentioned (8), it is characterized in that (9) above-mentioned stage portion is groove shape in the form of a ring.
In the charging device of above-mentioned (8) or (9), it is characterized in that (10) above-mentioned gap holding part part is the pipe with heat-shrinkable.
In any charging device of above-mentioned (8)-(10), it is characterized in that (11) above-mentioned gap holding part part is 100～300 μ m along above-mentioned charging unit radial thickness.
(12) in any charging device of above-mentioned (1)-(6), it is characterized in that,, form the charging gap through the gap holding part part that is made up of insulative resin is set at above-mentioned charging unit both ends.
(13) in any charging device of above-mentioned (1)-(6); It is characterized in that; At above-mentioned charging unit both ends the gap holding part part is set, forms the charging gap, make that above-mentioned charging unit and gap holding part part are integrated after; Cut is carried out on the surface, form the external diameter of above-mentioned charging unit and gap holding part part.
In any charging device of above-mentioned (7)-(13), it is characterized in that (14) above-mentioned gap holding part part hardness is more than JIS D standard 45 degree.
(15) a kind of cartridge processing is provided with integratedly as carrying and puts body and charging device, and the image forming device body loading and unloading is characterized in that above-mentioned charging device is any described charging device of above-mentioned (1)-(14) freely relatively.
(16) a kind of image processing system makes picture carry to put body charged through charging device, it is characterized in that above-mentioned charging device is any described charging device of above-mentioned (1)-(14).
(17) a kind of image processing system is provided with cartridge processing, and the image forming device body loading and unloading is characterized in that above-mentioned cartridge processing is the cartridge processing described in above-mentioned (15) freely relatively.
(18) in the image processing system of above-mentioned (16) or (17), it is characterized in that:
Above-mentioned charging unit is set, makes above-mentioned gap holding part part and the photographic layer that picture carries outside the image-region of putting body join;
Above-mentioned gap holding part part hardness is below JIS D standard 70 degree.
In the image processing system of above-mentioned (18), it is characterized in that (19) above-mentioned picture carries that to put body be Organophotoreceptor, contains metal oxide particle at outermost layer at least.
In the image processing system of above-mentioned (18) or (19), it is characterized in that (20) above-mentioned picture carries that to put body be Organophotoreceptor, contains lubricant particle at outermost layer at least.
(21) in any image processing system of above-mentioned (16)-(20), it is characterized in that:
To superimposed DC bias voltage and the AC bias voltage of applying of above-mentioned charging unit;
Satisfy following relational expression: 7 * V＜f＜12 * V, wherein f representes the frequency (Hz) of AC bias voltage, and V representes that picture carries the linear velocity (mm/s) of putting body;
At least in forming the image action, decide Control of Voltage AC bias voltage.
(22) a kind of charging gap establishing method, with charging unit and picture carry the charging gap of putting between the body be set in decide scope, it is characterized in that:
Through above-mentioned charging unit material condition is preestablished in deciding scope, through the change characteristic of this charging unit to environmental baseline itself, inhibition environmental baseline dynamic field closes and states the amplitude of fluctuation in charging gap.
(23) a kind of image processing system constitutes charging device by charging roller, and configuration charging device relatively picture carries that to put body be noncontact, it is characterized in that:
Above-mentioned charging roller is by metal-cored, and charging unit and gap holding part part constitute, and above-mentioned charging unit is made up of electroconductive resin, itself and metal-cored becoming one of periphery, and above-mentioned gap holding part part is made up of insulative resin, and it is installed in the charging unit two ends;
Be located at the gear of above-mentioned charging roller end and be located at picture and carry the gearing mesh of putting end of body; Above-mentioned charging roller and picture carry to be put body and is driven with speed about equally towards driving direction synchronously; The gear number of teeth of above-mentioned charging roller end is made as Nc; Above-mentioned picture carries the gear number of teeth of putting end of body and is made as Np, and the lowest common multiple of Nc and Np is Nc * Np.
(24) in the image processing system of above-mentioned (23), it is characterized in that:
Be made as G with the charging roller of optional position in the image forming area with as carrying the gap of putting between the body; Axial ad-hoc location in image forming area; Put the body revolution along with above-mentioned picture carries, charging roller and picture carry the maximal value of putting the gap between the body and are made as Gmax, and charging roller and picture carry the minimum value of putting the gap between the body and be made as Gmin; Putting axon to the optional position as carrying, below relation is set up:
20μm≤G≤80μm
Gmax-Gmin≤40μm
(25) in the image processing system of above-mentioned (23) or (24), it is characterized in that:
Be made as G with the charging roller of optional position in the image forming area with as carrying the gap of putting between the body; Circumferential ad-hoc location in image forming area; Above-mentioned picture carries puts body along direction of principal axis, and charging roller and picture carry the maximal value of putting the gap between the body and be made as Gmax, and charging roller and picture carry the minimum value of putting the gap between the body and be made as Gmin; Putting the circumferential optional position of body as carrying, below relation is set up:
20μm≤G≤80μm
Gmax-Gmin≤40μm
(26) a kind of image processing system constitutes charging device by charging roller, and configuration charging device relatively picture carries that to put body be noncontact, it is characterized in that:
Along picture carry put axon to, the image forming area middle position is made as C, two ends are made as E1, E2 respectively; In above-mentioned each position, along with carrying, above-mentioned picture puts the body revolution, and charging roller and picture carry the maximal value of putting the gap between the body and are made as Gmax (C) respectively, Gmax (E1); Gmax (E2), charging roller and picture carry the minimum value of putting the gap between the body and are made as Gmin (C) respectively, Gmin (E1), Gmin (E2); Above-mentioned Gmax (C), maximal value is made as Gmax, above-mentioned Gmin (C) among the Gmax (E1), Gmax (E2); Minimum value is made as Gmin among the Gmin (E1), Gmin (E2), and below relation is set up:
20μm≤Gmin(C，E1，E2)
Gmax(C，E1，E2)≤80μm
Gmax-Gmin≤40μm
(27) a kind of charging device; It is characterized in that; Be used for any described image processing system of above-mentioned (23)-(26), the gap holding part part is made up of insulative resin, is positioned at above-mentioned charging unit two ends; Make above-mentioned gap holding part part and the photographic layer that picture carries outside the image-region of putting body join, keep above-mentioned picture to carry the gap of putting between body and the charging unit.
(28) in the charging device of above-mentioned (27); It is characterized in that; At above-mentioned charging unit both ends stage portion is set; In this stage portion the gap holding part part that is made up of the insulative resin with heat-shrinkable is installed, is made above-mentioned gap holding part part and the photographic layer that picture carries outside the image-region of putting body join, keep above-mentioned picture to carry the gap of putting between body and the charging unit.
(29) a kind of charging device; It is characterized in that be used for any described image processing system of above-mentioned (23)-(26), the gap holding part part is made up of the insulative resin material; Its external diameter is bigger slightly than charging unit; This gap holding part part is installed in above-mentioned charging unit two ends, makes above-mentioned gap holding part part and the photographic layer that picture carries outside the image-region of putting body join, keep above-mentioned picture to carry the gap of putting between body and the charging unit.
(30) a kind of charging device manufacturing approach is characterized in that, is used to make above-mentioned (28) or (29) described charging device, makes after charging unit and gap holding part part are integrated, to form the shape of above-mentioned charging unit and gap holding part part by the electric conductivity supporting mass.
(31) a kind of image processing system is characterized in that, uses any described charging device in above-mentioned (27)-(29), and above-mentioned picture carries that to put body be Organophotoreceptor, contains metal oxide particle at outermost layer at least.
(32) a kind of image processing system is characterized in that, uses any described charging device in above-mentioned (27)-(29), and above-mentioned picture carries that to put body be Organophotoreceptor, contains lubricant particle at outermost layer at least.
(33) according to above-mentioned (23)-(26); (31)-(32) any described image processing system is characterized in that in, and above-mentioned charging roller is applied the charging bias voltage; This charging bias voltage is a stack AC bias voltage on the DC bias voltage, in forming the image action, decides Control of Voltage AC bias voltage at least.
(34) in the image processing system of above-mentioned (32), it is characterized in that, is to be provided with some pictures to carry the tandem coloured image of putting body and form device, can carry each picture to put body individual settings image and be applied to the AC bias voltage on each charging roller in forming.
(35) in the image processing system of above-mentioned (32) or (33), it is characterized in that, satisfy following relational expression: 7 * V＜f＜12 * V, wherein, f representes to be applied to the frequency (Hz) of the AC bias voltage on the above-mentioned charging roller, and V representes that picture carries the linear velocity (mm/s) of putting body.
(36) a kind of cartridge processing; It is characterized in that; Be used for above-mentioned (23)-(26), any described image processing system in (31)-(35) perhaps is provided with the image processing system of any described charging device in above-mentioned (27)-(29); At least carry by picture and put body and charging device constitutes, image forming device body loading and unloading relatively integratedly.
Effect of the present invention is described below.
According to invention described in above-mentioned (1), charging gap determinator and adjusting gear are not set, the environmental change in the gap that can reduce to charge is with the implemented with low cost high-durability.
According to invention described in above-mentioned (2), charging gap determinator and adjusting gear are not set, the environmental change in the gap that can reduce to charge is with the implemented with low cost high-durability.
According to invention described in above-mentioned (3), charging gap determinator and adjusting gear are not set, the environmental change in the gap that can reduce to charge, even environment for use changes, it is dirty to be difficult for that also the charging roller dirt takes place, and can also prevent paradoxical discharge.
According to invention described in above-mentioned (4), charging gap determinator and adjusting gear are not set, the environmental change in the gap that can reduce really to charge, even environment for use changes, it is dirty to be difficult for that also the charging roller dirt takes place, and can also prevent paradoxical discharge.
According to invention described in above-mentioned (5), charging gap determinator and adjusting gear are not set, the environmental change in the gap that can reduce to charge.
According to invention described in above-mentioned (6), with the rubber phase ratio, hardness is high, and handling ease can improve the manufacturing accuracy from electric parts.
According to invention described in above-mentioned (7), can obtain high-precision charging gap with low cost.
According to invention described in above-mentioned (8), can improve the permanance of gap holding part part.
According to invention described in above-mentioned (9), needn't use bonding agent etc., not occurrence positions skew ground assemblage gap holding member.
According to invention described in above-mentioned (10), can make the facilitation of gap holding part part installation exercise.
According to invention described in above-mentioned (11), can improve the permanance of gap holding part part, and can improve gap precision.
According to invention described in above-mentioned (12), can prevent that discharge from causing the photographic layer deterioration, prevent that toner etc. from adhering to.
According to above-mentioned (13), invention through one machining gap holding member and charging unit, can obtain high gap precision described in (30).
According to invention described in above-mentioned (14),, can reduce the temperature variation in charging gap through gap holding part part and charging unit two sides are made as high rigidity.
According to invention described in above-mentioned (15), demanding charging gap precision occasion need not adjusted the charging gap, and the user also can change simply as carrying and put body and charging unit.
According to invention described in above-mentioned (16),, therefore, has effect described in above-mentioned (1)-(14) because charging device is any described charging device of above-mentioned (1)-(14).
According to invention described in above-mentioned (17),, therefore, has effect described in above-mentioned (1)-(14) because cartridge processing is the cartridge processing described in above-mentioned (15).
According to invention described in above-mentioned (18), can not cause that device maximizes, can form the charging gap, because the gap holding part part can prevent the photographic layer deterioration.
According to above-mentioned (19), invention described in (31) through making metal oxide be dispersed in the photoreceptor top layer, improves physical strength, even gap holding part part and photographic layer join, also can further reduce the photographic layer deterioration.
According to above-mentioned (20), invention described in (32) through making lubricant be dispersed in the photoreceptor top layer, improves sliding, even gap holding part part and photographic layer join, also can further reduce the photographic layer deterioration.
According to above-mentioned (21), (33), invention described in (35) through superimposed AC bias voltage, is put gapped occasion between body and the charging unit as carrying, and also can make picture carry to put the body homogeneous charged.Put body linear velocity relation and be set in that to prevent concentration in the said scope irregular through AC bias voltage and picture are carried, can prevent toner or the adjuvant conjunctiva on photoreceptor.
According to invention described in above-mentioned (22), charging gap determinator and adjusting gear are not set, the environmental change in the gap that can reduce to charge is with the implemented with low cost high-durability.
According to the present invention, charging unit is made as resin system roll shape, and the resin with heat-shrinkable constitutes the gap holding part part; Make this gap holding part part and photoreceptor join; Form the charging gap, can obtain high-precision charging gap, provide gap holding part part permanance good charging device.
According to the present invention; Image processing system is provided, the variation in charging gap is constrained in institute decide scope, the dirt of minimizing charging roller is dirty; Prevent photoreceptor conjunctiva or photoreceptor abrasion; In this scope, it is dirty to reduce the charging roller dirt, prevents photoreceptor conjunctiva or photoreceptor abrasion through the gap deviation constraint of will charging.
According to the present invention; Image processing system is provided,, improves the physical strength of photoreceptor through making metal oxide particle be dispersed in the outermost layer of Organophotoreceptor; Even the outer photographic layer of gap holding part part and image-region joins; Also be difficult for abrasion or damage photoreceptor, improve the antifriction consumption of the photoreceptor in the image-region, prolong the photoreceptor life-span.
According to the present invention, along with photoreceptor and charging roller revolution charging gap change occasion, can make that also the photoreceptor homogeneous is charged, even each photoreceptor charging gap is different, also can set suitable charging bias voltage.
According to the present invention, put body and be made as one with charging device and constitute the cartridge processing form that is easy to change through looking like to carry, even need high gap precision charging modes, also be easy to change, do not need the adjusting play, the user also can be easy to replacing.
Description of drawings
Fig. 1 is that the summary as the color printer of image processing system of first embodiment of the invention constitutes front view (FV);
Fig. 2 is the detailed pie graph of the amplification of light sensitive body assembly;
Fig. 3 is the rhythmo structure sectional view of photoreceptor;
Fig. 4 is the sectional position figure of photoreceptor;
Fig. 5 is the sectional view of the rhythmo structure modified example of photoreceptor;
Fig. 6 is that the summary of the state that joins of charging roller and photoreceptor constitutes outboard profile;
Fig. 7 is that the summary of the state that joins of charging roller and the photoreceptor of second embodiment of the invention constitutes outboard profile;
Fig. 8 is the charging roller of second embodiment of the invention and the major part oblique view of gap holding part part assembled relation;
Fig. 9 is that the summary of the state that joins of charging roller and the photoreceptor of third embodiment of the invention constitutes outboard profile;
Figure 10 is the charging roller of third embodiment of the invention and the major part oblique view of gap holding part part assembled relation;
Figure 11 is the summary pie graph of the charging gap determinator of use in the experiment;
Figure 12 is the summary sectional view of the charging roller of fourth embodiment of the invention;
Figure 13 is the summary sectional view of the charging roller of fifth embodiment of the invention.
Embodiment
Below, present invention will be described in detail with reference to the accompanying embodiment.
With reference to Fig. 1-Fig. 6, explanation first embodiment of the invention.
Fig. 1 is that the whole summary of color printer of the direct transfer printing mode of the tandem type as image processing system of first embodiment of the invention constitutes front view (FV).
In device body 1, four light sensitive body assembly 2A are installed, 2B, 2C, 2D, it comprises as as carrying the photoreceptor 5 of putting body, can load and unload by relative device body 1 respectively.Light sensitive body assembly 2A; 2B, 2C, 2D have identical structure; Light sensitive body assembly 2A forms and the corresponding image of magenta (following brief note is " a M look "); Light sensitive body assembly 2B forms and the corresponding image of cyan (following brief note is " a C look "), and light sensitive body assembly 2C forms and yellow (following brief note is " a Y look ") corresponding image, and light sensitive body assembly 2D forms and the corresponding image of black (following brief note is " a Bk look ").
In the substantial middle of device body 1, configuration transfer printing assembly, it is installed in transfer belt 3 on some rollers, and transfer belt 3 can be turned round along the arrow A direction.Be provided with four transfer printing brushes 57 in transfer belt 3 inboards, it is corresponding with four photoreceptors 5 respectively.The face of transfer belt 3 upsides be configured to can with each light sensitive body assembly 2A, 2B, 2C, the photoreceptor 5 of 2D contacts.
With each light sensitive body assembly 2A, 2B, 2C, 2D is corresponding, configuration developing apparatus 10A, and 10B, 10C, 10D uses not homochromy toner respectively.Developing apparatus 10A, 10B, 10C, 10D are the developing apparatuss of two component visualization way, constitutes identical, the look of employed toner difference only.
Developing apparatus 10A uses the toner of M look, and developing apparatus 10B uses the toner of C look, and developing apparatus 10C uses the toner of Y look, and developing apparatus 10D uses the toner of Bk look.At each developing apparatus 10A, 10B, 10C is taking in the developer that is made up of toner and carrier in the 10D.
Developing apparatus 10A, 10B, 10C, 10D be by developer roll, spiral, formations such as toner concentration sensor.Above-mentioned developer roll and photoreceptor 5 subtends, its revolution development freely by the outside is overlapped and is fixed on inboard magnet and constitutes.Above-mentioned spiral is used to transport and stir developer, according to the output of toner concentration sensor, from the toner of toner supply device (not having diagram) supply necessary amount.
Toner is with binding resin, and colorant, charge control agent are major component, can add other adjuvants as required and constitute.
Concrete example as binding resin can use polystyrene, the multipolymer of cinnamic acrylic ester, vibrin etc.The colorant (for example yellow, magenta, green grass or young crops, black) that is used for toner can use material known, about the use amount of colorant, when its relative binding resin 100 weight portions are 0.1～15 weight portion, is suitable.
As the concrete example of charge control agent, can use for example Ni Geruoxin based dye, contain the complex compound of chromium, quaternary ammonium salts etc. use according to toner particle polarity.About the use amount of charge control agent, relative binding resin 100 weight portions, charge control agent is 0.1～10 weight portion.
Can in the toner particle, add flowability in advance and invest agent.Invest agent as flowability; Can use metal oxide microparticles such as silicon dioxide, aluminium oxide, titania; Through silane coupling agent, titanate coupling agent etc. above-mentioned metal oxide microparticle is carried out surface treatment gained person, polystyrene, polymethylmethacrylate, gather polymer particles such as ethylene fluoride etc.
The particle diameter that flowability invests agent is 0.01～3 mu m range.It is the scope of 0.1～7.0 weight portion that the addition that flowability invests agent is preferably relative toner particle 100 weight portions.
About double component developing involved in the present invention manufacturing approach with toner, can use various known methods, perhaps its combination is made.For example, in the comminuting method that mixes, with binding resin; Colorants such as carbon black, necessary adjuvant carries out dry mixed, at extruder; Or twin-roll machine, or three-roller etc. carries out heating and melting and mixes, behind the cooling curing; In comminutors such as jet pulverizer, pulverize, carry out classification through gas flow sizing machine again, obtain toner.
Also can pass through additive method for example suspension polymerization or non-aqueous dispersion polymerization method etc., from monomer, colorant, adjuvant are directly made toner.
Carrier generally uses by the institute of core constitutor own, or clad is set on core.In embodiments of the present invention, as the core of employable resin-coated carrier, can enumerate ferrite, magnet.This core particle diameter is to be suitable about 20～60 μ m.
As the material that is used to form the carrier clad, can enumerate tetrafluoroethene, difluoroethylene, hexafluoropropylene, perfluoroalkyl vinyl ether, the vinethene of displacement fluorine atom, the vinyl ketone of displacement fluorine atom etc.
Formation method as clad can be used known method, spray-on process for example, infusion process etc. with resin-coated on carrier core material particle surface.
At light sensitive body assembly 2A, 2B, 2C, the configuration of 2D top writes assembly 6, configuration double-side assembly 7 below transfer belt 3.This color printer is provided with upset assembly 8 at the left of device body 1, makes to form transfer paper (recording medium) P behind the image discharge of overturn, or it is transported to double-side assembly 7.
Write the light source of assembly 6 by four laser diodes (LD) mode by preparation of all kinds, one group of polygonal mirror scanner, and be configured in the f-θ lens in each light source light path, other lenses and reflective mirror constitute.Above-mentioned polygonal mirror scanner is made up of the polygonal mirror and the polygonal mirror motor that are six.The laser that penetrates from laser diode is deflected through the polygonal mirror scanner, is radiated at photoreceptor 5 enterprising line scannings.
Double-side assembly 7 is by transporting guide plate 45a, and 45b and some paired rollers 46 that transports constitute, and in the present embodiment, are four groups and transport roller 46.When being used for forming the dual-side image formation pattern of image on transfer paper P two sides, after single face formed image, transfer paper P was transported to the upset of upset assembly 8 and transports passage 54, again through this double-side assembly 7, it was transported to sheet feed section.
Upset assembly 8 paired transports roller and some paired guide plates that transports constitute by some; When being used for forming image on transfer paper P two sides; Make the transfer paper P surface and the back side overturn; Fortune perhaps maintains the original state row outside machine with transfer paper P to double-side assembly 7 after forming image, perhaps make transfer paper P surface and back side upset row outside machine.
Sheet feed section is provided with paper feeding cassette 11,12, is respectively equipped with to separate sheet feed section 55,56, is used for many ground separation transfer paper P and carries out paper supply.
Between transfer belt 3 and upset assembly 8, fixing device 9 is set, be used for the image of transfer printing on transfer paper P carried out photographic fixing.In the downstream along the transfer paper carriage direction of fixing device 9, bifurcated forms upset row paper passage 20, through a pair of exit roller 25, can transfer paper P be discharged on the paper platform 26.
As stated,, dispose paper feeding cassette 11,12 respectively, can take in the different transfer paper P of size at two lattice up and down in the bottom of device body 1.
At the right flank of device body 1, manual paper feeding cassette 13 is set, can open and close along the arrow B direction, should craft paper feeding cassette 13 through opening, can carry out manual paper supply from this.
Below, the action when the formation coloured image of color printer of present embodiment is described.
If color printer receives color image data, then each photoreceptor 5 is respectively towards revolution clockwise shown in Figure 1.Make that through charging roller 14 each photoreceptor 5 uniform surface is charged as charging unit.
Through writing assembly 6; Laser radiation that will be corresponding with the M color image is to the photoreceptor 5 of light sensitive body assembly 2A; Laser radiation that will be corresponding with the C color image is to the photoreceptor 5 of light sensitive body assembly 2B; Laser radiation that will be corresponding with the Y color image is to the photoreceptor 5 of light sensitive body assembly 2C, and laser radiation that will be corresponding with the bk color image forms the sub-image corresponding with view data of all kinds respectively to the photoreceptor 5 of light sensitive body assembly 2D.
Each photoreceptor 5 revolution, each sub-image arrives developing apparatus 10A respectively, 10B, 10C, the position of 10D, so, through M, C, Y, the toner of Bk look develops, and becomes four look toner pictures.
From paper feeding cassette 11 or 12, carry out paper supply through separating sheet feed section 55,56.The transfer paper P that supplies with sees off in the suitable time, so that transfer paper P is consistent with the toner picture on being formed on each photoreceptor 5 through being located at a pair of registration roller 59 near transfer belt 3.
Paper adsorption roller 58 is configured near the inlet of transfer belt 3, makes transfer paper P band positive polarity electricity through this paper adsorption roller 58, like this, transfer paper P by Electrostatic Absorption on transfer belt 3 surfaces.State is transported transfer paper P on the transfer belt 3 to be adsorbed on one side, on one side by order transfer printing M, and C, Y, the toner picture of Bk look finally forms four looks superimposed color toner image.
Then, at fixing device 9,, make toner on the transfer paper P as the fusion photographic fixing through applying heat and pressure; After this, according to specified pattern, through paper discharging system, upset is discharged on row's paper platform 26 on device body 1 top; Perhaps directly advance, in upset assembly 8, directly arrange paper, perhaps when selecting dual-side image to form pattern from fixing device 9; Be admitted to after upsets in the upset assembly 8 transport passage 54, be sent to double-side assembly 7, carry out paper supply again, be provided with light sensitive body assembly 2A; 2B, 2C, the imaging portion of 2D discharges after the transfer paper P back side forms image.After, when indication forms two or two with epigraph, above-mentioned repeatedly imaging processing.
Below, the action when the formation black white image of color printer of present embodiment is described.
Driven voller is configured in and adsorption roller 58 subtend positions, supporting transfer belt 3.If color printer receives the black white image data, then above-mentioned driven voller moves towards the below, and transfer belt 3 is left M, C, the photoreceptor 5 of Y look.
The photoreceptor 5 of Bk look makes that through charging roller 14 photoreceptor 5 uniform surface of Bk look charged towards revolution clockwise shown in Figure 1.Through writing assembly 6, laser radiation that will be corresponding with the bk color image forms sub-image to the photoreceptor 5 of light sensitive body assembly 2D.When the position of sub-image arrival developing apparatus 10D, the toner through the Bk look develops, and becomes the toner picture.
At this moment, the light sensitive body assembly 2A of other three looks beyond the Bk, 2B, 2C, developing apparatus 10A, 10B, 10C stops, and prevents photoreceptor 5 losses, and the unnecessary consumption that prevents developer.
From paper feeding cassette 11 or 12, carry out paper supply through separating sheet feed section 55,56.The transfer paper P that supplies with sees off in the suitable time, so that transfer paper P is consistent with the toner picture on the photoreceptor that is formed on the Bk look 5 through being located at a pair of registration roller 59 near transfer belt 3.
Make transfer paper P band positive polarity electricity through paper adsorption roller 58, transfer paper P by Electrostatic Absorption on transfer belt 3 surfaces.Because transfer paper P is to be transported by Electrostatic Absorption state on transfer belt 3, transfer paper P is transported to the photoreceptor 5 of Bk look, the toner picture of transfer printing Bk look.
In order stably to transport transfer paper P with the Electrostatic Absorption state, transfer belt 3 top layer at least must constitute with high-resistance material.
The coloured image occasion is identical with forming, and at fixing device 9, makes toner on the transfer paper P as the fusion photographic fixing, after this, and according to specified pattern, by handling as stated.
As the material of transfer belt 3, can use for example Kynoar, polyimide, polycarbonate, molding resin materials such as polyethylene terephthalate are seamless band.These materials can not adjusted resistance and use, also can be through using behind conductive agents such as the carbon black adjustment resistance.
Also can form the top layer through spraying or impregnating method, constitute rhythmo structure with above-mentioned resin material as basic unit.
Fig. 2 representes light sensitive body assembly 2A, 2B, 2C, the formation of 2D; Each light sensitive body assembly 2A, 2B, 2C; 2D is by the photoreceptor that is used to form electrostatic latent image 5, makes the charging roller 14 that photoreceptor 5 homogeneous are charged, is used to clean the formations such as brush roll 15 and cleaning balde 47 on photoreceptor 5 surfaces.
The gap holding part part is located at the both ends of charging roller 14, and itself and the outer photosensitive surface (photographic layer) of image-region join, and between charging roller 14 and photoreceptor 5, at image forming area, forms minim gap.
Clearer 49 joins with charging roller 14, is used for the clearer surface.Clearer 49 is on the metallic core, conducting fibre static to be planted the brush roll that hair forms, and leans on deadweight and charging roller 14 to join, along with conductive rollers 14 revolutions, driven revolution on one side, one side is cleaned, and removes attached to charging roller 14 lip-deep toners etc.In the present embodiment, by charging roller 14, charging bias voltage applying device (not diagram), clearer 49 grades constitute charging device, and above-mentioned charging bias voltage applying device applies the charging bias voltage to charging roller 14.
Cleaning balde 47 is made up of Desmocoll, scrapes from photoreceptor 5 through this cleaning balde 47 and gets toner, makes that with brush roll 15 scraping the toner of getting moves to toner and transport spiral 48 sides.Through making toner transport spiral 48 revolutions, make the useless toner that reclaims be transported to useless toner incorporating section 18 shown in Figure 1.
In the present embodiment, photoreceptor 5 external diameters are 30mm, and each photoreceptor 5 turns round with the 125mm/sec linear velocity towards the arrow C direction respectively.Brush roll 15 is synchronous with photoreceptor 5 revolutions, turns round towards counterclockwise.
At light sensitive body assembly 2A, 2B, 2C, the last location primary standard portion 51 that is provided with of 2D, the benchmark when loading and unloading as relative device body 1, simultaneously, the location, front side is located at respectively on the carriage 50 from benchmark portion 53 from benchmark portion 52 and inboard location.When with light sensitive body assembly 2A, when 2B, 2C, 2D are installed in the device body 1, according to said reference portion, can be really with light sensitive body assembly 2A, 2B, 2C, 2D are positioned at the installation site that sets.
At this, also can be so that light sensitive body assembly 2A, 2B, 2C, 2D constitute the cartridge processing form that the user is easy to change, and photoreceptor 5 and charging roller 14 are constituted a cartridge processing.In cartridge processing; Location positioning structure through photoreceptor 5 and charging roller 14 when as the present invention, need precision form small charging gap occasion well between photoreceptor 5 and charging roller 14; Because photoreceptor 5 is changed with charging roller 14 simultaneously; There is no need adjustment charging gap, therefore, user self also can change.
At this, with photoreceptor 5, charging roller 14, cleaning device become one to example is illustrated, but in also can developing apparatus being also included within, constitute the cartridge processing of one, also can cleaning device be constituted another cartridge.
Fig. 3 representes the formation of employable in the present embodiment photoreceptor 5, is the rhythmo structure sectional view of photoreceptor, and the part of the half section of photoreceptor 5 is looked in expression sideways from the arrow L of Fig. 4.
Photoreceptor 5 has rhythmo structure, and photographic layer 202 is formed on the electric conductivity supporting mass 201, and photographic layer 202 comprises charge generating layer 203 and charge transport layer 204, and protective seam 205 is located at outermost layer.
Also can be as shown in Figure 5, on electric conductivity supporting mass 201, charge transport layer 204 is set, charge generating layer 203 is provided with protective seam 205 more above that.
In addition, also can between electric conductivity supporting mass 201 and photographic layer 202, form bottom.
Electric conductivity supporting mass 201 uses has volume resistance 10 4The material of the electric conductivity below the Ω cm, for example, with aluminium, metals such as metal tube such as stainless steel or nickel are processed into endless belt-shaped.
Bottom is main composition with resin generally, uses solvent application photographic layer 202 above that owing to considering, is preferably, and uses the resin high to the common organic solvents dissolubility resistent.As this resin, can enumerate water soluble resins such as polyvinyl alcohol (PVA), pure soluble resins such as copolymerization nylon, polycarbamate, alkyd-melamine, epoxy etc. form the cancellated hardening resin of ternary etc.In addition,, reduce residual electric potential, also can in bottom, add metal oxide micropowders such as titanium dioxide, silicon dioxide, aluminium oxide in order to prevent to ripple.This bottom can use suitable solvent application method to form.The bottom thickness is advisable with 0～5 μ m.
Charge generating layer is main composition with the electric charge generating material, representationally can enumerate monoazo dyes, two diazonium dyestuffs, trisazo dyes, phthalocyanines dye.With resin glues such as these electric charge generating materials and polycarbonate together, use tetrahydrofuran, the cyclohexanone equal solvent disperses, and forms through the coating dispersion liquid.Coating can be carried out through dipping coating method or spraying process etc.Charge generating layer 203 thickness are generally 0.01～5 μ m.
Charge transport layer 204 is through the dissolving of charge transport material and binding resin is dispersed in tetrahydrofuran, and toluene in the suitable solvent such as ethylene dichloride, forms the dry back of its coating again.
Charge transport material comprises low molecule charge transport material, and low molecule charge transport material has electron transport materials and hole transporting material.Can enumerate for example Spergon as electron transport materials, tetrabromo 1,4-benzoquinone, TCNE, four cyano quinone dimetan (tetracyanoquinodimethane); 2,4,7-trinitro--9-fluorine lubricating ester, 2; 4,5,7-tetranitro-9-fluorine lubricating ester, 1; 3,7-trinitro-dibenzothiophene-5, electron-acceptor materials such as 5-dioxide.Can enumerate for example oxazole derivatives as hole transporting material, oxadiazoles derivant, imdazole derivatives, triphenylamine derivant; Phenyl hydrazones, α-phenyl stilbene derivatives, thiazole, triazole derivative; The azophenlyene derivant, acridine derivatives, electron donability materials such as thiophene derivant.As the binding resin that uses with charge transport material in charge transport layer, can enumerate for example polystyrene, styrene-acrylonitrile copolymer; SB, polyester, polyarylate; Polycarbonate, acrylic resin, epoxy resin; Melamine resin, thermoplasticity or thermosetting resins such as phenolics.
The thickness of charge transport layer 204 can suitably be selected in 15～30 mu m ranges according to desirable photoreceptor characteristic.
In the photoreceptor 5 of present embodiment, in order to protect photographic layer 202, and improve permanance, can on photographic layer 202, form the protective seam 205 that contains the burning particulate.
As the material that is used for protective seam 205, can use binding resin and solvent.As binding resin, can enumerate for example styrene-acrylonitrile copolymer, SB, acrylonitrile-butadiene-styrene copolymer, alkene-vinyl monomer multipolymer; Chlorinated polyether resin, aryl resin, phenolics, polyacetal resin, polyamide; Polyamide-imide resin, polyacrylate resin, polyaryl sulfone (polyarylsulfone) resin, polybutene resin, polybutylene terephthalate resin; Polycarbonate resin, polyethersulfone resin, polyvinyl resin, polyethylene terephthalate resin, polyimide resin; Acrylic resin, polymethylpentene (polymethylpentene) resin, acrylic resin, polyphenylene oxide (polyphenyleneoxide) resin, polysulfone resin; Polyurethane resin, Corvic, polychlorostyrene vinylidene resin, epoxy resin etc.As solvent, can enumerate for example tetrahydrofuran, toluene, ethylene dichloride etc.
In order to improve the antifriction consumption, can in these resins, add aluminium oxide, silicon dioxide, oxidation phthalein, tin oxide, zirconia, metal oxide particles such as indium oxide.
Add the amount of the metal oxide particle in the protective seam 205 to,, be generally 5～40%, be preferably 10～30% as if being benchmark with weight.Metal oxide particle is if be discontented with 5%, and abrasion is big, poor durability, if surpass 40%, bright current potential rises significantly during exposure, and sensitivity is low.
Formation method as protective seam 205 can be used rubbing methods such as spraying process.The thickness of protective seam 205 is advisable with 1～10 μ m, about preferred 3～8 μ m.If protective seam 205 thickness are thin excessively, poor durability, and if protective seam 205 thickness are blocked up, and productivity is low when making photoreceptor, and as time passes, residual electric potential rises big.
Adding the particle diameter of the metal oxide particle in the protective seam 205 to is advisable with 0.1～0.8 μ m.The excessive occasion of the particle diameter of metal oxide particle, protective seam 205 concave-convex surfaces are big, and spatter property is poor, and the laser that makes public is easy at random at protective seam 205, and resolution is low, image quality.The too small occasion of the particle diameter of metal oxide particle, the antifriction consumption is poor.
In the present embodiment, in order to improve the lubricity on photoreceptor 5 surfaces, also can be so that the such lubricant particle of fluororesin particle is distributed in the protective seam 205.About adding the amount of the fluororesin in the superficial layer to, be preferably, the full solid of apparent surface's layer, containing ratio are 40～75 weight %.The fluororesin amount is discontented with 40 weight %, and it is little that lubricity is improved effect, and the fluororesin amount surpasses 75 weight %, and film strength is low.
As the fluororesin that adds in the protective seam 205, can use teflon, polyhexafluoropropylene gathers trifluoro-ethylene, PVDF, PVF etc.The fluororesin particle diameter is advisable with 0.1～5 μ m.
In protective seam 205, make lubricant particle disperse occasion, also identical with the metal oxide particle occasion, use binding resin and solvent to disperse, be coated with through methods such as sprayings.The superficial layer thickness is preferably 3～8 μ m.
In protective seam 205, not only can make lubricant particle or metal oxide particle disperse separately, also can be so that both disperse.In order to improve metal oxide particle or fluororesin dispersion of nano-particles property, can also add disperse additive.The disperse additive that is added can use the disperse additive that is used for coating etc. suitably.In protective seam 205, it is also very effective to add charge transport material.Can also add antioxidant as required.
Fig. 6 representes the structure of charging roller.Charging roller 14 comprises as the pole shape of electric conductivity supporting mass metal-cored 101, the charged layer 102 that constitutes with the electroconductive resin material, and the gap holding part part 103 of sheet.Above-mentioned gap holding part part 103 is located at the both ends (say, be the both ends of charged layer 102 tightly) of charging roller 14.
Above-mentioned gap holding part part 103 joins with outer photosensitive surface (photographic layer) 5b of the image-region 5a of photoreceptor 5, at image-region 5a, between charged layer 102 and photoreceptor 5, forms small charging gap g.In Fig. 6, symbol 5c representes the non-finish department (non-photographic layer portion) of photoreceptor 5.
Through making above-mentioned gap holding part part 103 join with photographic layer, between charged layer 102 and gap holding part part 103, need not be provided for the interval of anti-heads, can prevent that locking apparatus maximizes.
Metals such as metal-cored 101 use stainless steels.If metal-cored 101 is meticulous, then can not ignore when charged layer 102 carried out cut or the influence of the deflection of photoreceptor when pressurized, be difficult to obtain necessary gap precision.If metal-cored 101 is thick excessively, cause that then charging roller 14 maximizes, quality is big, and therefore, metal-cored 101 diameters hope to be about 6～10mm.
Be preferably, charged layer 102 materials have 10 4～10 9The volume resistance of Ω cm.If resistance is low excessively, be cause because of the small resistance of charged layer 102 is irregular, the discharge condition heterogeneity, it is irregular to be prone to that charging takes place, if too high in resistance, discharge can not fully take place, and can not obtain the charging potential of homogeneous.
Can in resin, cooperate conductive material, obtain desirable volume resistance as charged layer 102 matrix materials.As the matrix material resin, can use for example tygon, polypropylene, polymethyl methyl esters, polystyrene, acrylonitrile-butadiene-styrene copolymer (ABS), resins such as polycarbonate.These matrix material resin shapings are good, and processing easily is shaped.
As conductive material, be preferably, have the such ionic conductivity material of macromolecular compound of quaternary ammonium base, for example, have the tygon or the polyolefin of quaternary ammonium base.These macromolecular compounds with quaternary ammonium base are known for people.
In the present embodiment, though illustration have the polyolefin of quaternary ammonium base, also can use the macromolecular compound beyond the polyolefin with quaternary ammonium base.
The ionic conductivity material is through using the twin shaft muller, and devices such as mixer enter into the matrix material resin equably.Can with this composite material be ejected on metal-cored 101 and be shaped, perhaps extrusion molding is easy to be configured as the roller shape.Use level about ionic conductivity material and matrix material resin is preferably, relative matrix material resin 100 weight portions, ionic conductivity material 30～80 weight portions.
The thickness of charged layer 102 is preferably 0.5～3mm.If charged layer 102 is thin excessively, difficult forming also has problems on the intensity.If charged layer 102 is blocked up, charging roller 14 maximizes, and the change of charged layer 102 resistance is big, and charge efficiency is low.
Also can be on charged layer 102 through methods such as sprayings, form the top layer that the toner of tens μ m degree thickness is difficult for adhering to.
Gap holding part part 103 is at polyester, polyethylene terephthalate, and the single face coating cementing agent of resin sheets such as polyimide constitutes, and is bonded in the end of charged layer 102 through cementing agent.Therefore, gap g is corresponding with resin sheet thickness in fact.
At this, to the both ends oblique cutting respectively as the resin sheet of gap holding part part 103, it is superimposed to avoid that resin sheet takes place, or avoids occurring in the circumferential generation of roller and do not have the resin sheet part.
End metal-cored 101 is equipped with gear; Also be formed with gear (all less than diagram) in photoreceptor 5 ends; Above-mentioned two gearing mesh are when photoreceptor drive motor photoreceptor turns round, through the said gear transmission; Charging roller 14 is towards being driven the direction revolution, with the linear velocity revolution that roughly equates with photoreceptor 5.
Because charged layer 102 does not contact with photoreceptor 5, even use the animi resin material, use Organophotoreceptor as photoreceptor 5 occasions as charged layer 102, can the regional photographic layer of damage image yet.
If gap g is excessive in charging, paradoxical discharge can take place, can not charge by homogeneous, experimental result learns that the maximal clearance is necessary to be suppressed to below the 100 μ m, is preferably below the 90 μ m.
For this reason, photoreceptor 5 and all necessary high precision of charging roller 14 are preferably, and linearity is below the 20 μ m.
In this formation, when the variation of ambient temperature occasion, as the main cause that charging gap g changes, the hardness variation influence of charged layer 102 is top dog.Because the thickness of gap holding part part 103 is tens μ m, even variation of ambient temperature, the thickness of gap holding part part 103 or the influence of hardness variation almost do not have.
Therefore, in order to reduce the environmental change of charging gap g, make charged layer 102 very effective for high rigidity, experimental result is learnt, if more than the hardness of charged layer 102 50 degree (JIS D standard), can reduce the environmental change of charging gap g significantly.
At this; Though the hardness of the material of charged layer 102 own is also very important; But the variation of charging gap g receives the thickness effect of charged layer 102 also very big, therefore; Hardness in the present embodiment is not meant the material hardness of charged layer 102, is that the sclerometer of standard is measured and obtained being processed into charged layer 102 behind the charging roller 14 and be to use with JIS K7215.
Below, with reference to Fig. 7 and Fig. 8 second embodiment of the invention is described.Part same as the previously described embodiments representes that with prosign (following other embodiment too) omitted in repeat specification.
In the present embodiment, form stage portion at charging roller 14 both ends, along this charging roller 14 radially have a degree of depth, through the gap holding part part is arranged on this stage portion, form the charging gap.
Charging roller 14 comprises the metal-cored 104 of roll shape, charged layer 105, and gap holding part part 106.Above-mentioned metal-cored 104 have the axial region of minor diameter at both ends, above-mentioned gap holding part part 106 is located at the both ends (say, be the both ends of charged layer 105 tightly) of charging roller 14.
When the charged layer 105 that is formed on metal-cored 104 is cut processing (comprising technologies such as cutting and grinding) when processing external diameter; Form the stage portion 105a of endless groove shape in advance in the end of charged layer 105; Be used for assemblage gap holding member 106; Heat-shrinkable tube 106 is installed as gap holding part part 106 in this stage portion; Can enumerate tetrafluoroethene-perfluoroalkyl vinyl ether multipolymer (tetrafluoroethylene-perfluoroalkylvinylether copolymers as the material of above-mentioned heat-shrinkable tube 106; Below brief note is " PFA ") or tetrafluoraoethylene-hexafluoropropylene copolymer fluorine-type resin materials such as (tetrafluoroethylene-hexafluoropropylene copolymers, below brief note is " FEP ").After the installation, heat, with chimeric with stage portion 105a.
Above-mentioned resin release property is good, is difficult for taking place the fixed phenomenon of toner.Add the fluorine-type resin that uses insulativity, can not discharge, can prevent the toner electrostatic adhesion in gap holding part part 106 positions.
Because at the gap holding part part 106 of concave shape (endless groove shape) installation heat-shrinkable, axially the step of both sides has positioning action, even do not use cementing agent etc., gap holding part part 106 can not break away from yet.
The depth d that is formed on the stage portion 105a of charged layer 105 can be by the thickness t of employed heat-shrinkable tube 106 and the size decision of target charging gap g.Through forming stage portion 105a at charged layer 105, can thicken the radial thickness of gap holding part part 106, therefore, compare with the method for bonding sheet gap holding part part 103, improved the permanance of gap holding part part 106.
But,, then can not ignore the variation of the charging gap g that the wall thickness deviation of heat-shrinkable tube 106 causes if heat-shrinkable tube 106 thickness are blocked up.
Experimental result learns that the thickness t of heat-shrinkable tube 106 is preferably 100～300 mu m ranges.Be in the heat-shrinkable tube 106 of this thickness range through installation, can obtain enough permanance, and have good gap precision.
In the present embodiment, the variation of ambient temperature occasion, as the main cause that charging gap g changes, the hardness variation influence of charged layer 105 is top dog.Although the thickness of gap holding part part 106 is thicker than sheet gap holding part part 103, because than charged layer 105 thin thickness, the thickness of gap holding part part 106 or hardness variation influence are little.
Therefore, in order to reduce the environmental change of charging gap g, make charged layer 105 very effective for high rigidity, experimental result is learnt, if more than the hardness of charged layer 105 50 degree (JIS D standard), can reduce the environmental change of charging gap g.
Below, with reference to Fig. 9 and Figure 10 third embodiment of the invention is described.
In the present embodiment, it is metal-cored 104 that charging roller 14 comprises, charged layer 107, and gap holding part part 108.Above-mentioned gap holding part part 108 is located at the both ends (say, be metal-cored 104 both ends tightly) of charging roller 14.
Behind the shaping charged layer 107; With gap holding part part 108 crimping that are shaped in advance or be bonded in metal-cored 104 both ends; Like this, charging roller 14 (say, be metal-cored 104 tightly) and gap holding part part 108 becoming one; The cutting that comprises technologies such as cutting and grinding is handled, processing charging roller 14 external diameters.
Like this, metal-cored 104 is consistent with the swing position of gap holding part part 108, can reduce charging gap g and change.
As gap holding part part 108, also can be the same with charged layer 107, use electroconductive resin, still,, there is no need to discharge because gap holding part part 108 joins outward with image-region.Therefore, cause deterioration in order to prevent photographic layer because of discharge, prevent that toner etc. from adhering to, be preferably, gap holding part part 108 uses the insulativity materials.
As make metal-cored 104 with the method for gap holding part part 108 becoming one, be not limited to above-mentioned crimping or bonding, also can be through double-colored shaping, 108 liang of kind resins of shaping charged layer 107 and gap holding part part on metal-cored 104.
As the material of gap holding part part 108, can enumerate propylene, polybutylene gathers isoprene; Ethylene-ethyl acrylate copolymer, ethylene-methyl acrylate copolymer, vinyl-vinyl acetate copolymer, ethylene-propylene copolymer; Resins such as ethene-hexene copolymer also can be the same with the charging unit matrix material, uses for example tygon, polypropylene; Gather the methyl methacrylate, polystyrene, acrylonitrile-butadiene-styrene copolymer, resins such as polycarbonate etc.
But,,, preferably use than the low degree of charged layer 107 hardness in order to prevent to damage photographic layer 202 because gap holding part part 108 joins with photographic layer 202.As the good resin material of easy damaged photographic layer 202 and sliding not, can use resins such as Kynoar, PFA, FEP.
In the present embodiment; Gap holding part part 108 is installed on metal-cored 104, if constitute charged layer 107, variation of ambient temperature occasion with high hardness material; As the main cause that charging gap g changes, the hardness variation influence of gap holding part part 108 is top dog.
Therefore, in order to reduce the environmental change of charging gap g, make gap holding part part 108 very effective for high rigidity, experimental result is learnt, if more than the hardness of gap holding part part 108 45 degree (JIS D standard), can reduce the environmental change of charging gap g.
At this, if the hardness of gap holding part part 108 is too high, when gap holding part part 108 and photographic layer 202 joined, photographic layer 202 was prone to deterioration, and photoreceptor 5 permanance become problem.Experimental result is learnt, if below the hardness of gap holding part part 108 70 degree (JIS D standard), be difficult for photographic layer 202 deteriorations that generation causes because of gap holding part part 108.
Form charging gap g occasion, along with the revolution of photoreceptor 5 and charging roller 14, usually, charging gap g changes in certain limit.Under this situation; In order to make photoreceptor 5 homogeneous charged; Following method is very effective: for the charging bias voltage that is applied on the charging roller 14, be stack AC bias voltage on dc voltage, this AC bias voltage has the PV more than 2 times of the discharge ionization voltage between charging roller 14 and the photoreceptor 5.
Experimental result learns, if the AC bias frequency that is applied is low, therefore striated charged clearly irregular, be preferably, and is the frequency f more than 7 times (Hz) of photoreceptor linear velocity V (mm/s) with this frequency setting.
Superfluous discharge takes place in the too high occasion of AC bias frequency that is applied, and the abrasion amount of photoreceptor 5 increases; Or easy toner or the adjuvant film forming on photoreceptor 5 of taking place; Therefore, being preferably, is the frequency f below 12 times (Hz) of photoreceptor linear velocity V (mm/s) with this frequency setting.
Superimposed AC bias voltage occasion if the AC bias voltage is made as and decides Current Control, then is not vulnerable to the roller changes in resistance that causes because of environment.But when charging roller 14 and photoreceptor 5 noncontacts configuration occasion, along with the revolution of charging roller 14 and photoreceptor 5, charging gap g changes, and is deciding under the Current Control, and high-voltage power supply can not be followed the variation of charging gap g sometimes, and abnormal image takes place.Therefore, the AC bias voltage preferably is made as and decides Control of Voltage.At this moment, necessary AC voltage is different because of the environmental change or the charging gap length of roller resistance, and roller resistance is high more, and the charging gap is big more, needs high voltage more.For this reason, the AC electric current can be detected, when not forming image,,, proper A C voltage can be set at Yi Bian adjust AC voltage Yi Bian keep watch on the AC electric current.
The assay method of charging gap g is described below.Figure 11 represent to charge formation skeleton diagram of gap determinator.Light sensitive body assembly is equipped with charging roller 14 and photoreceptor 5, and this light sensitive body assembly is set to charging gap determinator 60.Penetrate laser from illuminating part 61, this laser is injected light accepting part 62 through the charging gap, like this, can measure the charging gap.Can use Mitutoyo system laser scanning mircrometer gauge LSM-600 as charging gap determinator.In this installs, drive photoreceptor 5 through drive source (not diagram), make photoreceptor 5 and charging roller 14 turn round, under this state, can measure the charging gap.
Illuminating part 61 can constitute one with light accepting part 62, can move along the length direction of photoreceptor 5, can measure the charging gap in the optional position of photoreceptor length direction.Through using this charging gap determinator, can be with charging gap equal in high-precision measuring and the actual machine.
According to the present invention, the adjustment means in the gap of need not charging can reduce Yin Wendu and the variation that causes in charging gap significantly.
Experimental result can be known; Minimum value through the gap g that will charge is set at more than the 15 μ m; The toner dirt that can reduce charging roller 14 surface is dirty, and the maximal value through the gap g that will charge is set at below the 90 μ m, and it is irregular to prevent the concentration that causes because of paradoxical discharge.
Charge when the amplitude of variation of the mean value of charging gap g becomes 20 ℃ of environment temperatures when making when environment temperature is 10 ℃ the mean value of charging gap g be 30 ℃ with environment temperature below 1/5 of mean value of gap g; Can not exist with ... environment for use, stable maintenance charging gap.Through following instance 1 its reason of explanation.
Instance 1
The charging roller A-F that gives an example below and form according to the foregoing description,
Charging roller A
On the diameter 8mm that is made up of stainless steel metal-cored, form charged layer through injection molding forming, (specific insulation is 10 to this charged layer by resin combination 6Ω cm) constitute, above-mentioned resin combination cooperates ionic conductive agent 60 weight portions to obtain in ABS resin 100 weight portions, and above-mentioned ionic conductive agent is made up of the polyalkenes macromolecular compound with quaternary ammonium base.The bonding gap holding part part at the charged layer both ends, this gap holding part part is at width 8mm, adds on the film of the polyethylene terephthalate system of thick 45 μ m that the adhesive linkage of 15 μ m constitutes.The charged layer external diameter is 11mm, makes above-mentioned such charging roller (constituting identical with Fig. 6).The hardness of measuring the charged layer of this charging roller is 63 degree (JIS D standard).
Charging roller B
Use the metal-cored and electroconductive resin identical, be made into the roller shape through injection molding forming with above-mentioned charging roller A.When cutting this roller formation external diameter,, form width 8mm at the charged layer both ends; The stage portion of the endless groove shape of the degree of depth 100 μ m, heating is 20 minutes in 120 ℃ of environment temperatures, through thermal shrinkage; The PFA pipe is installed in above-mentioned stage portion, and the thickness after the thermal shrinkage becomes 150 μ m.Making the charged layer external diameter is the charging roller (constituting identical with Fig. 7) of 11mm.The hardness of measuring the charged layer of this charging roller is 63 degree (JIS D standard).
Charging roller C
Use the metal-cored and electroconductive resin identical, be made into the roller shape through injection molding forming with charging roller A.Through after being pressed into gap holding part part with the high density polyethylene system of 8mm and being installed to the both ends of above-mentioned roller, cut charged layer and gap holding part part simultaneously, making charged layer external diameter is the charging roller (constituting identical with Fig. 9) of 11mm.Measure the hardness (JIS D standard) of the charged layer and the gap holding part part of this charging roller, charged layer is 63 degree, and the gap holding part part is 58 degree.
Charging roller D
Except the material with the gap holding part part of charging roller C changes to polyacetal, other are identical with charging roller C, make charging roller.Measure the hardness (JIS D standard) of the charged layer and the gap holding part part of this charging roller, charged layer is 63 degree, and the gap holding part part is 75 degree.
Charging roller E
On the diameter 8mm that constitutes by stainless steel metal-cored; The charged layer that formation is made up of chloromethyl oxirane rubber; The bonding gap holding part part at the charged layer both ends; This gap holding part part is identical with above-mentioned charging roller A, is at width 8mm, adds on the film of the polyethylene terephthalate system of thick 45 μ m that the adhesive linkage of 15 μ m constitutes.Making the charged layer external diameter is the charging roller of 11mm.The hardness of measuring the charged layer of this charging roller is 29 degree (JIS D standard).
Charging roller F
On the diameter 9mm that constitutes by stainless steel metal-cored; The charged layer that formation is made up of chloromethyl oxirane rubber; The bonding gap holding part part at the charged layer both ends; This gap holding part part is identical with above-mentioned charging roller A, is at width 8mm, adds on the film of the polyethylene terephthalate system of thick 45 μ m that the adhesive linkage of 15 μ m constitutes.Making the charged layer external diameter is the charging roller of 11mm.The hardness of measuring the charged layer of this charging roller is 33 degree (JIS D standard).
Use these charging rollers, use the colored 8110 improvement machines of the corporate system IPSIO of Ricoh to estimate.Employed photoreceptor is the bottom at the aluminum substrate superimposed layer 3.5 μ m of diameter 30mm, the charge generating layer of 0.15 μ m, and the charge transport layer of 22 μ m, the superficial layer of 5 μ m constitutes.
In the present embodiment, carry out the protective seam coating through spraying process, other are carried out through the dip coated method.
Charge transport layer and superficial layer all use polycarbonate as binding resin, and at superficial layer, the full solid of apparent surface's layer adds the aluminium oxide particles of 25 weight % mean grain sizes, 0.3 μ m.
Above-mentioned charging roller and photoreceptor are arranged in the light sensitive body assembly, use above-mentioned charging gap determinator under various environment, to measure the charging gap, measure the result and be illustrated in the table 1, wherein represent the mean value in this charging gap.At this, be the influence of variation in the charging gap of cause in order to reduce as far as possible because of the photoreceptor form accuracy, the mensuration of each charging roller is all used same photoreceptor.
Table 1
Can know that from table 1 charging roller E is a rubber rollers, the charging gap that is caused by environment changes greatly, although use the gap holding part part identical with charging roller A, A compares with charging roller, and charging gap itself is little, and this can think the influence of roller hardness.
Be appreciated that from table 1; Charge when the amplitude of variation of the mean value of charging gap g became 20 ℃ of environment temperatures when the mean value through the time charging gap g that makes that environment temperature is 10 ℃ was 30 ℃ with environment temperature below 1/5 of mean value of gap g; Can not exist with ... environment for use, stable maintenance charging gap.
The environment temperature of present embodiment is the middle part of device action scope for 20 ℃, and environment temperature is the lower limit side of device action scope for 10 ℃, and environment temperature is the upper limit side of device action scope for 30 ℃.Certainly, the segmentation of environment temperature is set and is not limited thereto.
Under above-mentioned three kinds of environment, carry out 20000 logical paper test respectively.Processing speed is 125mm/s, applies the charging bias voltage, and it is that (frequency f=900Hz)+DC (700V) for AC.At this moment, experimental enviroment switches to successively: 20 ℃ of temperature, 30 ℃ of humidity 60% → temperature, 10 ℃ of humidity 54% → temperature, humidity 15%.
Logical paper test findings
Charging roller A: although at the photographic layer of the connecting position of gap holding part part damage is arranged slightly, image does not note abnormalities.
Charging roller B: with 30 ℃ of temperature, when humidity 54% was led to paper, although the dirty dirty deterioration that has slightly of charging roller, 10 ℃ of temperature, under humidity 15% environment, image did not note abnormalities.
Charging roller C: although at the photographic layer of the connecting position of gap holding part part damage is arranged slightly, image does not note abnormalities.
Charging roller D: adding up to 35000 logical paper constantly, at the connecting position of gap holding part part, photographic layer is damaged, and the charging bias voltage leaks, and can not continue logical paper.The dirty dirty almost not generation of charging roller.
Charging roller E: with 30 ℃ of temperature, when humidity 54% was led to paper, charging roller was obviously polluted because of toner, 10 ℃ of temperature, under humidity 15% environment, was cause because of the charging roller dirt is dirty, and the generation charging is bad, causes concentration irregular.
Charging roller F: with 30 ℃ of temperature, when humidity 54% was led to paper, although do not reach charging roller E degree, charging roller was still dirty dirty because of toner, 10 ℃ of temperature, under humidity 15% environment, was cause because of the charging roller dirt is dirty, and it is bad to take place to charge, and causes concentration irregular.
The The above results summary sheet is shown in the table 2.
Table 2
Charging roller G 20/(G 30-G 10) The roller dirt is dirty The photoreceptor damage
A
26 ○ ○
B 6.1 ○ ○
C 15.7 ○ ○
D 54 ○ ×
E 0.86 × ○
F 1.95 × ○
Wherein, G 10, G 20, G 30Represent that respectively environment temperature is 10 ℃, 20 ℃, the mean value in the charging gap in the time of 30 ℃.
Can know that from table 2 temperature variation in charging gap is more little, G 20/ (G 30-G 10) value big more, the dirty dirty difficult more generation of charging roller.
Therefore, if G 20/ (G 30-G 10) value greater than 5, can make dirty dirty being difficult to of charging roller take place.That is, through satisfying | G 30-G 10| * 5＜G 20Condition can make dirty dirty being difficult to of charging roller take place.
The photoreceptor deterioration be prone to take place in the too high occasion of gap holding part part hardness, with charging roller C; The formation that D is identical, change gap holding part part material makes hardness variation; Estimate the experiment of gap holding part part hardness and photoreceptor deterioration, the result is illustrated in the table 3.
Table 3
The gap holding part part Hardness The photoreceptor outward appearance
EEA 44 ◎
LDPE 46 ◎
HDPE 58 ○
POM 65 ○
PP 69 ○
POM 75 ×
ABS 82 ×
In evaluation, use the charging roller that each gap holding part part is installed, use the colored 8100 improvement machines of the corporate system IPSIO of Ricoh, the test of leading to 10000 on paper, the photoreceptor outward appearance of the gap holding part part connecting position after the evaluation test.
In table 3, ◎ representes with prima facies same, and zero presentation surface has damage slightly, and it is coarse that * presentation surface becomes.
About gap holding part part material, HDPE representes high density polyethylene, and LDPE representes low density polyethylene, and PP representes polypropylene, and EEA representes ethylene-ethyl acrylate copolymer, and POM representes polyacetal, and ABS representes acrylonitrile-butadiene-styrene copolymer.
As shown in table 3, no matter material how, gap holding part part hardness is high more; Easier giving and the photosensitive body surface surface damage; If the gap holding part part uses the material below hardness 70 degree (JIS D standard), can reduce the photosensitive body surface surface damage, reach the level that does not have endurance issues.
In one embodiment of this invention, as stated, gear is installed in metal-cored 101 end; Also be formed with gear (all less than diagram) in photoreceptor 5 ends; Above-mentioned two gearing mesh are when photoreceptor drive motor photoreceptor turns round, through the said gear transmission; Charging roller 14 is towards being driven the direction revolution, with the linear velocity revolution that roughly equates with photoreceptor 5.
The gear number of teeth of charging roller 14 sides is made as Nc, the gear number of teeth of photoreceptor 5 sides that drive this charging roller 14 is made as Np, the lowest common multiple of Nc and Np is Nc * Np.Lowest common multiple through with Nc and Np is set at Nc * Np, can prolong the cycle of the mutual subtend of ad-hoc location of photoreceptor and charging roller, like this, can make that photoreceptor partial film forming or abrasion are difficult for taking place.
Optional position in image forming area; Gap between charging roller 14 and the photoreceptor 5 is made as g, and axial ad-hoc location in image forming area is along with photoreceptor 5 revolutions; The maximal value of gap g between charging roller 14 and the photoreceptor 5 is made as Gmax; Minimum value is made as Gmin, carry at picture and putting axon to the optional position, below two formulas set up:
20μm≤g≤80μm
Gmax-Gmin≤40μm
Optional position in image forming area, the gap between charging roller 14 and the photoreceptor 5 is made as g, in image forming area; The ad-hoc location of Zhou Fangxiang; Axial along photoreceptor 5, the maximal value of the gap g between charging roller 14 and the photoreceptor 5 is made as Gmax, and minimum value is made as Gmin; Carry at picture and to put body Zhou Fangxiang optional position, below two formulas set up:
20μm≤g≤80μm
Gmax-Gmin≤40μm
Figure 12 is the summary sectional view of the charging roller of fourth embodiment of the invention, and charging roller 14 is by the metal-cored 14a as the electric conductivity supporting mass, the charging unit 14b that constitutes by the electroconductive resin material, and gap holding part part 14c constitutes.
Metal-cored 14a uses metals such as stainless steel, if metal-cored meticulous, in the time of can not ignoring the cut of charging unit 14b or the influence of the deflection when receiving photoreceptor 5 pressurizations, is difficult to obtain necessary gap precision.If metal-cored 14a is thick excessively, charging roller 14 maximizes, and quality is heavy, and therefore, the maximum gauge of metal-cored 14a is preferably about 6～10mm.
Be preferably, charging unit 14b material has 10 4～10 9The volume resistance of Ω cm.If resistance is low excessively, defective occasions such as pore are arranged on photoreceptor 5, be prone to take place the charging bias voltage and leak, if too high in resistance, discharge can not fully take place, and can not obtain the charging potential of homogeneous.
Can in resin, cooperate conductive material, obtain desirable volume resistance as charging unit 14b matrix material.As the matrix material resin, can use for example tygon, polypropylene, polymethyl methyl esters, polystyrene, acrylonitrile-butadiene-styrene copolymer (ABS), resins such as polycarbonate.These matrix material resin shapings are good, and processing easily is shaped.
As conductive material, be preferably, have the such ionic conductivity material of macromolecular compound of quaternary ammonium base, for example, have the polyolefin of quaternary ammonium base.These macromolecular compounds with quaternary ammonium base are known for people.
In the present embodiment, though illustration have the polyolefin of quaternary ammonium base, also can use the macromolecular compound beyond the polyolefin with quaternary ammonium base.
The ionic conductivity material is through using the twin shaft muller, and devices such as mixer are coupled in the matrix material resin equably.Can with this composite material be ejected into metal-cored 14a and go up be shaped, perhaps extrusion molding is easy to be configured as the roller shape.Use level about ionic conductivity material and matrix material resin is preferably, relative matrix material resin 100 weight portions, ionic conductivity material 30～80 weight portions.
The thickness of charging unit 14b is preferably 0.5～3mm.If charging unit 14b is thin excessively, difficult forming also has problems on the intensity.If charging unit 14b is blocked up, charging roller 14 maximizes, and the change of charging unit 14b resistance is big, and charge efficiency is low.
Behind the shaping charging unit 14b, with the gap holding part part 14c crimping that is shaped in advance or be bonded in the axial both ends of this charging unit 14b, perhaps use crimping and bonding simultaneously, be fixed on the metal-cored 14a.
Like this, charging unit 14b and becoming one of gap holding part part 14c, the cutting that then comprises technologies such as cutting and grinding is handled, processing charging roller 14 external diameters.Make that the swing position of charging unit 14b and gap holding part part 14c is consistent, can reduce the charging gap and change.
As making the method for charging unit 14b and becoming one of gap holding part part 14c, be not limited to above-mentioned crimping or bonding, also can be through double-colored shaping, shaping charging unit 14b and gap holding part part 14c two kind resins on metal-cored 14a.
As the material of gap holding part part 14c, the same with the matrix material of charging unit 14b, can enumerate for example tygon, polypropylene gathers the methyl methacrylate, polystyrene, acrylonitrile-butadiene-styrene copolymer, resins such as polycarbonate etc.
But, because gap holding part part 14c and photographic layer join,, be preferably in order to prevent to damage photographic layer, use than the low degree of charging unit 14b hardness.
As the good resin material of easy damaged photographic layer and sliding not, can use polyacetal, ethylene-ethyl acrylate copolymer, Kynoar, PFA, resins such as FEP.
Also can be on resin bed or gap holding part part 14c through methods such as sprayings, form the top layer that the toner of tens μ m degree thickness is difficult for adhering to.
Make gap holding part part 14c and the outer photographic layer of the image-region that is positioned at the axial two ends of drum type photoreceptor join, between the resin bed of charging roller 14 and photoreceptor 5, form the gap.
End at metal-cored 14a is equipped with gear; Also be formed with gear (all less than diagram) in photoreceptor 5 ends; Above-mentioned two gearing mesh are when 5 revolutions of photoreceptor drive motor photoreceptor, through the said gear transmission; Charging roller 14 is towards being driven the direction revolution, with the linear velocity revolution that roughly equates with photoreceptor 5.
Because charging unit 14b does not contact with photoreceptor 5, even use the animi resin material, use Organophotoreceptor as photoreceptor 5 occasions as charging unit, can the regional photographic layer of damage image yet.
If paradoxical discharge can take place in the charging excesssive gap, can not charge by homogeneous, therefore, the maximal clearance is necessary to be suppressed to below the 100 μ m, is preferably below the 90 μ m, is preferably below the 80 μ m.
But this maximal clearance is relevant with the material of charging unit 14b, and for this reason, photoreceptor 5 and all necessary high precision of charging roller 14 are preferably, and linearity is below the 20 μ m.
In technology in the past; Make the former pipe of gap holding part part and the photoreceptor occasion of joining; For the bias voltage that prevents to charge leaks from the charging unit end to the former pipe of photoreceptor; Necessary photosensitive coated layer, must join with the former pipe exposed portion in the photographic layer outside in order to make the former pipe of gap holding part part and photoreceptor join up to the charging unit outside.
Therefore, the former pipe of photoreceptor must be very long, causes that device maximizes.To this, in the present invention, use to be difficult for giving the gap holding part part 14c that damages with photographic layer, perhaps use on the photographic layer surface protective seam is set, the photoreceptor that physical strength is good and lubricity is good makes gap holding part part 14c to join with photographic layer.
Therefore, shown in figure 12, can be with charging unit 14b and gap holding part part 14c in abutting connection with configuration, the former pipe of photoreceptor that there is no need to extend can prevent that locking apparatus maximizes.
In the present invention, make gap holding part part 14c not join, but join with photographic layer with the former pipe of photoreceptor; Therefore, even being the electric conductivity material, also can use gap holding part part 14c, still; In order to prevent unnecessary discharge; In order to prevent that electrostatic adhesion such as toner to gap holding part part 14c surface, is preferably, gap holding part part 14c adopts the high resistance material.
In configuration charging unit 14b and photoreceptor 5 non-contacting image processing systems, will look like year to put axon to the image forming area middle position be made as C, two ends are made as E1 respectively; E2, with each position along with photoreceptor 5 revolution the time the maximal value in gap between charging roller 14 and the photoreceptor 5 be made as Gmax (C) respectively, Gmax (E1); Gmax (E2), maximal value wherein is made as Gmax, and the minimum value in above-mentioned gap is made as Gmin (C) respectively; Gmin (E1); Gmin (E2), minimum value wherein is made as Gmin, each relational expression below satisfying:
20μm≤Gmin(C，E1，E2)
Gmax(C，E1，E2)≤80μm
Gmax-Gmin≤40μm
Figure 13 is the summary sectional view of the charging roller of fifth embodiment of the invention, shaping charging unit 14b on metal-cored 14a, and 14b cuts to this charging unit; When grindings etc. are processed to form external diameter; In the end of charging unit 14b, form stage portion 14b ', this stage portion can be recess or projection etc.; Be recess in the present embodiment, be used for gap holding part part 14c stably is installed in correct position.
The heat-shrinkable tube that can use fluorine-type resin materials such as PFA or FEP is as gap holding part part 14c.
Above-mentioned resin release property is good, is difficult for taking place the fixed phenomenon of toner.Add the fluorine-type resin that uses insulativity, can not discharge, can prevent the toner electrostatic adhesion in gap holding part part position.
Because the concave shape stage portion 14b ' such at Figure 13 goes up the gap holding part part 14c that heat-shrinkable is installed, step has positioning action, even do not use cementing agent etc., gap holding part part 14c can not break away from yet.
The step degree of depth that is formed on the charging unit 14b can be by employed heat-shrinkable tube thickness and the decision of target charging gap length.
Owing between charging roller 14 and photoreceptor 5, be provided with the gap, the revolution load concentration of charging roller 14 requires high-durability at heat-shrinkable tube to heat-shrinkable tube.
In technology in the past, on the charging unit surface, the gap holding part part of the thin ribbon shaped about bonding thickness 50 μ m, when charging unit is the resin occasion, thin ribbon shaped gap holding part part is prone to abrasion, can not obtain enough permanance.
But, in the present embodiment, on charging unit 14b, form step, through the heat-shrinkable tube of thickness 150～300 μ m is installed, can obtain enough permanance.
Generally, heat-shrinkable tube has about 10% wall thickness deviation of thickness, and heat-shrinkable tube thickness is blocked up, although permanance is improved, because of wall thickness deviation is a cause, the charging gap changes greatly, becomes undesirable condition.
Between charging roller 14 and photoreceptor 5, form the gap occasion, along with the revolution of photoreceptor 5 and charging roller 14, the gap changes in certain limit usually.Under this situation; In order to make photoreceptor 5 homogeneous charged; Following method is very effective: for the charging bias voltage that is applied on the charging unit 14b; Be stack AC bias voltage on dc voltage, this AC bias voltage has the PV more than 2 times of the discharge ionization voltage between charging unit 14b and the photoreceptor 5.
At this, if the AC bias frequency that applied is low, therefore striated charged clearly irregular, be preferably, and is the frequency f more than 7 times (Hz) of photoreceptor linear velocity V (mm/s) with this frequency setting.
Superfluous discharge takes place in the too high occasion of AC bias frequency that is applied, and the abrasion amount of photoreceptor 5 increases; Or easy toner or the adjuvant film forming on photoreceptor 5 of taking place; Therefore, being preferably, is the frequency f below 12 times (Hz) of photoreceptor linear velocity V (mm/s) with this frequency setting.
For example, the AC bias frequency f (Hz) and the photoreceptor 5 linear velocity V (mm/s) that are applied on the charging roller 14 satisfy following relation:
7×V＜f＜12×V
Superimposed AC bias voltage occasion if the AC bias voltage is made as and decides Current Control, then is not vulnerable to the roller changes in resistance that causes because of environment.But when occasion is disposed in charging roller 14 and photoreceptor 5 noncontacts, along with the revolution of charging roller 14 and photoreceptor 5, the charging gap changes, and is deciding under the Current Control, and high-voltage power supply can not be followed the variation of charging gap sometimes, and abnormal image takes place.Therefore, the AC bias voltage preferably is made as and decides Control of Voltage.At this moment, necessary AC voltage is different because of the environmental change or the charging gap length of roller resistance, and roller resistance is high more, and the charging gap is big more, needs high voltage more.For this reason, the AC electric current can be detected, when not forming image,,, proper A C voltage can be set at Yi Bian adjust AC voltage Yi Bian keep watch on the AC electric current.
Once more with reference to Fig. 1, developing device 10A～10D is the developing apparatus of two component visualization way, is taking in the developer that is made up of toner and carrier, constitutes all identical, the look of employed toner difference only.
Developing apparatus 10A, 10B, 10C, 10D be by developer roll, spiral, formations such as toner concentration sensor.Above-mentioned developer roll and photoreceptor 5 subtends, its revolution development freely by the outside is overlapped and is fixed on inboard magnet and constitutes.Above-mentioned spiral is used to transport and stir developer, according to the output of toner concentration sensor, from the toner of toner supply device (not having diagram) supply necessary amount.
Toner is with binding resin, and colorant, charge control agent are major component, can add other adjuvants as required and constitute.
Concrete example as binding resin can use polystyrene, the multipolymer of cinnamic acrylic ester, vibrin etc.
The colorant (for example yellow, magenta, green grass or young crops, black) that is used for toner can use material known, about the use amount of colorant, when its relative binding resin 100 weight portions are 0.1～15 weight portion, is suitable.
As the concrete example of charge control agent, can use for example Ni Geruoxin based dye, contain the complex compound of chromium, quaternary ammonium salts etc. use according to toner particle polarity.About the use amount of charge control agent, relative binding resin 100 weight portions, charge control agent is 0.1～10 weight portion.
Can in the toner particle, add flowability in advance and invest agent.Invest agent as flowability; Can use metal oxide microparticles such as silicon dioxide, aluminium oxide, titania; Through silane coupling agent, titanate coupling agent etc. above-mentioned metal oxide microparticle is carried out surface treatment gained person, polymer particles such as polystyrene, polymethylmethacrylate, Kynoar etc.
The particle diameter that flowability invests agent is 0.01～3 mu m range.It is the scope of 0.1～7.0 weight portion that the addition that flowability invests agent is preferably relative toner particle 100 weight portions.
About double component developing involved in the present invention manufacturing approach with toner, can use various known methods, perhaps its combination is made.For example, in the comminuting method that mixes, with binding resin; Colorants such as carbon black, necessary adjuvant carries out dry mixed, at extruder; Or twin-roll machine, or three-roller etc. carries out heating and melting and mixes, behind the cooling curing; In comminutors such as jet pulverizer, pulverize, carry out classification through gas flow sizing machine again, obtain toner.
Also can pass through additive method for example suspension polymerization or non-aqueous dispersion polymerization method etc., from monomer, colorant, adjuvant are directly made toner.
Carrier generally uses by the institute of core constitutor own, or clad is set on core.In embodiments of the present invention, as the core of employable resin-coated carrier, can enumerate ferrite, magnet.This core particle diameter is to be suitable about 20～60 μ m.
As the material that is used to form the carrier clad, can enumerate tetrafluoroethene, difluoroethylene, hexafluoropropylene, perfluoroalkyl vinyl ether, the vinethene of displacement fluorine atom, the vinyl ketone of displacement fluorine atom etc.
Formation method as clad can be used known method, spray-on process for example, infusion process etc. with resin-coated on carrier core material particle surface.
About charging gap determinator, use above-mentioned device shown in Figure 11, light sensitive body assembly is equipped with charging roller 14 and photoreceptor 5, and this light sensitive body assembly is set to charging gap determinator 60.
Penetrate laser from illuminating part 61, this laser is injected light accepting part 62 through the charging gap, like this, can measure the charging gap.Can use Mitutoyo system laser scanning mircrometer gauge LSM-600 as charging gap determinator.In this installs, drive photoreceptor 5 through drive source (not diagram), make photoreceptor 5 and charging roller 14 turn round, under this state, can measure the charging gap.
Illuminating part 61 can constitute one with light accepting part 62, can move along the length direction of photoreceptor 5, can measure the charging gap in the optional position of photoreceptor length direction.
According to a sixth embodiment of the invention, make charging roller 14 as follows:
On the diameter 8mm that is made up of stainless steel metal-cored, form charging unit 14b through injection molding forming, (specific insulation is 10 to this charging unit by resin combination 6Ω cm) constitute, above-mentioned resin combination cooperates ionic conductive agent 60 weight portions to obtain in ABS resin 100 weight portions, and above-mentioned ionic conductive agent is made up of the polyalkenes macromolecular compound with quaternary ammonium base.
The gap holding part part 14c of bonded polyethylene system at charging unit 14b two ends then, carries out grinding, makes the external diameter difference of charging unit 14b and gap holding part part 14c become 50 μ m, makes the charging roller (constituting identical with Figure 12) of diameter 12mm.
According to a seventh embodiment of the invention, make charging roller 14 as follows:
Charging roller identical materials among use and above-mentioned the 4th embodiment is made charging roller 14, and still, condition during the change grinding makes the roller swing greatly.
According to the eighth embodiment of the present invention, make charging roller 14 as follows:
Use with above-mentioned the 4th embodiment in identical metal-cored 14a and the electroconductive resin of charging roller, through injection molding forming, the making roller.During this roller of grinding, form the concave shape step at charging unit 14b two ends, the PFA pipe to thickness 150 μ m in 120 ℃ environment temperature carries out heating in 20 minutes, installs through thermal shrinkage, becomes gap holding part part 14c.
It is poor to make that the external diameter of charging unit 14b and gap holding part part 14c after the thermal shrinkage forms ladder, and the external diameter difference becomes 50 μ m in the present embodiment, makes the charging roller 14 (constituting identical with Figure 13) of diameter 12mm.
According to the nineth embodiment of the present invention, make charging roller 14 as follows:
Charging roller identical materials among use and above-mentioned the 8th embodiment is made charging roller.But, when forming the concave shape step at charging unit 14b two ends, make the ladder difference change in depth at two ends, so that the charging gap produces deviation.
According to the tenth embodiment of the present invention, make charging roller 14 as follows:
Charging roller identical materials among use and above-mentioned the 8th embodiment is made charging roller.But, when forming the concave shape step at charging unit 14b two ends, make the ladder difference change in depth at two ends, so that make that charging gap deviation ratio charging roller 14 deviations are big.
Use above-mentioned charging roller 14, use the corporate system IPSIO of Ricoh colored 8100 to estimate.Employed photoreceptor is the bottom at the aluminum substrate superimposed layer 3.5 μ m of diameter 30mm, the charge generating layer of 0.15 μ m, and the charge transport layer of 22 μ m, the superficial layer of 5 μ m constitutes.
In the present embodiment, carry out the protective seam coating through spraying process, other are carried out through the dip coated method.
Charge transport layer and superficial layer all use polycarbonate as binding resin, and at superficial layer, the full solid of apparent surface's layer adds the aluminium oxide particles of 25 weight % mean grain sizes, 0.3 μ m.The photoreceptor external diameter that uses in each experiment, the deviation of precision such as linearity and each charging roller low precision out-phase ratio are fully little.
Above-mentioned charging roller 14 and photoreceptor 5 are arranged on light sensitive body assembly for example among the 2A, use above-mentioned charging gap determinator 60 in each position finding charging gap, the amplitude of variation in the charging gap of being measured is illustrated in the table 4.Wherein, measure the charging gap and carry out, the image-region end of E1 indication device front side, C presentation video zone middle position, the image-region end that the E2 indication device is inboard in the image-region central authorities of photoreceptor length direction and three places at both ends.At this, the gear number of teeth of charging roller is made as 13, and the gear number of teeth of photoreceptor is made as 35.
Table 4
Figure S2008101253026D00391
Figure S2008101253026D00401
Below, each roller is arranged in the basic machine, set suitable charging bias voltage.When the not enough occasion of charging AC bias voltage; Especially in half tone image white point can take place, stain shape abnormal image, therefore; Increase the Vp-p of charging AC voltage gradually; Seek the Vp-p that abnormal image does not take place, under this is set, carry out 20000 logical paper test, the photoreceptor 5 after evaluation output image and the test of logical paper and the outward appearance of charging roller 14.
In above-mentioned 20000 logical paper test and evaluation test, processing speed: 125mm/s, charging bias voltage: AC (frequency f=900Hz)+DC is (700V).
Instance 2
In the instance 2 of logical paper test, use the charging roller 14 of above-mentioned the 6th embodiment to estimate.When charging AC voltage is low, white point takes place at both ends, stain shape abnormal image when the Vp-p of the AC voltage that will charge is set at 2.1kV, can obtain no problem initial pictures, therefore, leads to the paper test with this setting.
After 20000 logical paper test outputs, image and photoreceptor outward appearance are not unusual yet.The charging roller cleaning brush is attached with toner slightly, but charging roller 14 itself does not have significantly dirt not dirty.
Instance 3
In the instance 3 of logical paper test, use the charging roller 14 of above-mentioned the 8th embodiment to estimate.When charging AC voltage is low, white point takes place at both ends, stain shape abnormal image when the AC voltage Vp-p that will charge is set at 2.2kV, can obtain no problem initial pictures, therefore, leads to the paper test with this setting.
After 20000 logical paper test outputs, image and photoreceptor outward appearance are not unusual yet.The charging roller cleaning brush is attached with toner slightly, but charging roller 14 itself does not have significantly dirt not dirty.
Comparative example 1
Use the charging roller 14 of above-mentioned the 7th embodiment to estimate as comparative example 1.When charging AC voltage is low, white point takes place at both ends, stain shape abnormal image when the AC voltage Vp-p that will charge is set at 2.2kV, can obtain no problem initial pictures, therefore, leads to the paper test with this setting.
In the half tone image after 20000 logical paper test output, the concentration of central portion generation vertical stripe shape is irregular.Though the photoreceptor outward appearance is not unusual, charging roller 14 central portions are polluted by toner.
Dirty dirty with this charging roller 14 of cloth xerotripsis, but can not remove, can remove with alcohol wipe.On with the charging roller after the alcohol wipe 14, abnormal image does not take place, therefore, can think, because it is dirty dirty on charging roller 14, to be attached with toner etc., cause the irregular phenomenon of concentration of vertical stripe shape.
Comparative example 2
Use the charging roller 14 of above-mentioned the 9th embodiment to estimate as comparative example 2.When charging AC voltage was low, at the inboard white point that takes place of device body, stain shape abnormal image when the AC voltage Vp-p that will charge is set at 2.4kV, can obtain no problem initial pictures, therefore, leads to the paper test with this setting.
In the half tone image after 20000 logical paper test output, the concentration of the vertical stripe shape that the generation of device body front side is quite serious is irregular.The toner conjunctiva takes place in photoreceptor 5 front sides, and charging roller 14 is also polluted by toner in the front side.
Comparative example 3
Use the charging roller 14 of above-mentioned the tenth embodiment to estimate as comparative example 3.Inboard at body, in 14 cycles, the squamous abnormal image takes place at charging roller, even charging AC voltage Vp-p increases to 2.7kV, the body inboard is can not homogeneous charged.Can not obtain the initial pictures of homogeneous, lead to the paper test with this setting.
In the half tone image after 10000 logical paper test output; The concentration that quite serious vertical stripe shape takes place in the body front side is irregular; Inboard at body; Take place with prima facies with the squamous abnormal image, the toner conjunctiva takes place in photoreceptor 5 front sides, charging roller 14 also in the front side by the toner severe contamination.
As stated, in the image processing system with charging roller 14 and photoreceptor 5 noncontacts configuration, there is the upper limit in the charging gap that abnormal image does not take place, if the charging gap surpasses the upper limit, increases charging AC bias voltage howsoever, can not make that photoreceptor 5 homogeneous are charged.
Charging gap below the upper limit, the charging gap is big more, need to set big more charging AC voltage Vp-p, in order to make its homogeneous charged, must be set at the charging AC voltage Vp-p of such size: even charging gap largest portion is also can homogeneous charged.
At this moment, if charging gap deviation is big, the narrow part in the charging gap, discharge energy is superfluous, on photoreceptor 5, is prone to take place the toner conjunctiva.In addition, the charging gap is narrow, and it is dirty dirty that the big place of charging AC voltage Vp-p is prone to take place charging roller 14.
In the image processing system that uses non-contact charge roller 14, in order to obtain image steady in a long-term, the gap that needs to charge is suppressed to below the charged upper limit of ability homogeneous, amplitude of fluctuation or the deviation that also need dwindle the charging gap as far as possible.
Above with reference to description of drawings embodiments of the invention, but the present invention is not limited to the foregoing description.In technological thought scope of the present invention, can do all changes, they all belong to protection scope of the present invention.

Claims (14)

1. an image processing system constitutes charging device by charging roller, and configuration charging device relatively picture carries that to put body be noncontact, it is characterized in that:
Above-mentioned charging roller is by metal-cored, and charging unit and gap holding part part constitute, and above-mentioned charging unit is made up of electroconductive resin, itself and metal-cored becoming one of periphery, and above-mentioned gap holding part part is made up of insulative resin, and it is installed in the charging unit two ends;
Be located at the gear of above-mentioned charging roller end and be located at picture and carry the gearing mesh of putting end of body; Above-mentioned charging roller and picture carry to be put body and is driven with speed about equally towards driving direction synchronously; The gear number of teeth of above-mentioned charging roller end is made as Nc; Above-mentioned picture carries the gear number of teeth of putting end of body and is made as Np, and the lowest common multiple of Nc and Np is Nc * Np.
2. image processing system according to claim 1 is characterized in that:
Be made as G with the charging roller of optional position in the image forming area with as carrying the gap of putting between the body; Axial ad-hoc location in image forming area; Put the body revolution along with above-mentioned picture carries, charging roller and picture carry the maximal value of putting the gap between the body and are made as Gmax, and charging roller and picture carry the minimum value of putting the gap between the body and be made as Gmin; Putting axon to the optional position as carrying, below relation is set up:
20μm≤G≤80μm
Gmax-Gmin≤40μm。
3. image processing system according to claim 1 and 2 is characterized in that:
Be made as G with the charging roller of optional position in the image forming area with as carrying the gap of putting between the body; Circumferential ad-hoc location in image forming area; Above-mentioned picture carries puts body along direction of principal axis, and charging roller and picture carry the maximal value of putting the gap between the body and be made as Gmax, and charging roller and picture carry the minimum value of putting the gap between the body and be made as Gmin; Putting the circumferential optional position of body as carrying, below relation is set up:
20μm≤G≤80μm
Gmax-Gmin≤40μm。
4. charging device; It is characterized in that; Be used for each described image processing system of claim 1-3, the gap holding part part is made up of insulative resin, is positioned at above-mentioned charging unit two ends; Make above-mentioned gap holding part part and the photographic layer that picture carries outside the image-region of putting body join, keep above-mentioned picture to carry the gap of putting between body and the charging unit.
5. charging device according to claim 4; It is characterized in that; At above-mentioned charging unit both ends stage portion is set; In this stage portion the gap holding part part that is made up of the insulative resin with heat-shrinkable is installed, is made above-mentioned gap holding part part and the photographic layer that picture carries outside the image-region of putting body join, keep above-mentioned picture to carry the gap of putting between body and the charging unit.
6. charging device; It is characterized in that be used for each described image processing system of claim 1-3, the gap holding part part is made up of the insulative resin material; Its external diameter is bigger slightly than charging unit; This gap holding part part is installed in above-mentioned charging unit two ends, makes above-mentioned gap holding part part and the photographic layer that picture carries outside the image-region of putting body join, keep above-mentioned picture to carry the gap of putting between body and the charging unit.
7. a charging device manufacturing approach is characterized in that, is used to make claim 5 or 6 described charging devices, makes after charging unit and gap holding part part are integrated, to form the shape of above-mentioned charging unit and gap holding part part by the electric conductivity supporting mass.
8. an image processing system is characterized in that, uses each described charging device among the claim 4-6, and above-mentioned picture carries that to put body be Organophotoreceptor, contains metal oxide particle at outermost layer at least.
9. an image processing system is characterized in that, uses each described charging device among the claim 4-6, and above-mentioned picture carries that to put body be Organophotoreceptor, contains lubricant particle at outermost layer at least.
10. according to claim 1-2; Each described image processing system is characterized in that among the 8-9, and above-mentioned charging roller is applied the charging bias voltage; This charging bias voltage is a stack AC bias voltage on the DC bias voltage, in forming the image action, said AC bias voltage is carried out deciding Current Control at least.
11. image processing system according to claim 9 is characterized in that, is to be provided with some pictures to carry the tandem coloured image of putting body and form device, can carry each picture and put body individual settings image and be applied to the AC bias voltage on each charging roller in forming.
12. image processing system according to claim 9 is characterized in that, satisfies following relational expression: 7 * V＜f＜12 * V, wherein, f representes to be applied to the frequency (Hz) of the AC bias voltage on the above-mentioned charging roller, and V representes that picture carries the linear velocity (mm/s) of putting body.
13. image processing system according to claim 10 is characterized in that, satisfies following relational expression: 7 * V＜f＜12 * V, wherein, f representes to be applied to the frequency (Hz) of the AC bias voltage on the above-mentioned charging roller, and V representes that picture carries the linear velocity (mm/s) of putting body.
14. cartridge processing; It is characterized in that; Be used for claim 1-3, any described image processing system among the 8-13 perhaps is provided with the image processing system of any described charging device among the claim 4-6; At least carry by picture and put body and charging device constitutes, image forming device body loading and unloading relatively integratedly.
CN2008101253026A 2004-01-09 2005-01-10 Electrifying device, process cartridge and image forming apparatus Expired - Fee Related CN101320238B (en)

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
JP2004004318A JP2005196052A (en) 2004-01-09 2004-01-09 Electrifying device, process cartridge, image forming apparatus, and method for setting electrifying gap
JP004318/04 2004-01-09
JP296877/04 2004-10-08
JP2004296877A JP4420784B2 (en) 2004-05-06 2004-10-08 Image forming apparatus and process cartridge

Related Parent Applications (1)

Application Number Title Priority Date Filing Date
CNB2005100036362A Division CN100409114C (en) 2004-01-09 2005-01-10 Charging unit,process cartridge and image forming apparatus

Publications (2)

Publication Number Publication Date
CN101320238A CN101320238A (en) 2008-12-10
CN101320238B true CN101320238B (en) 2012-03-21

Family

ID=34818968

Family Applications (1)

Application Number Title Priority Date Filing Date
CN2008101253026A Expired - Fee Related CN101320238B (en) 2004-01-09 2005-01-10 Electrifying device, process cartridge and image forming apparatus

Country Status (2)

Country Link
JP (1) JP2005196052A (en)
CN (1) CN101320238B (en)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP5678009B2 (en) * 2012-08-01 2015-02-25 京セラドキュメントソリューションズ株式会社 Image forming apparatus

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6240268B1 (en) * 1999-01-14 2001-05-29 Canon Kabushiki Kaisha Gap retaining member and developing device employing the same
JP2003066693A (en) * 2001-08-23 2003-03-05 Fuji Xerox Co Ltd Electrifying roller and image forming device equipped therewith
EP1331526A1 (en) * 2000-11-02 2003-07-30 Ricoh Company, Ltd. Imaging apparatus

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6240268B1 (en) * 1999-01-14 2001-05-29 Canon Kabushiki Kaisha Gap retaining member and developing device employing the same
EP1331526A1 (en) * 2000-11-02 2003-07-30 Ricoh Company, Ltd. Imaging apparatus
JP2003066693A (en) * 2001-08-23 2003-03-05 Fuji Xerox Co Ltd Electrifying roller and image forming device equipped therewith

Also Published As

Publication number Publication date
CN101320238A (en) 2008-12-10
JP2005196052A (en) 2005-07-21

Similar Documents

Publication Publication Date Title
CN100409114C (en) Charging unit,process cartridge and image forming apparatus
US7113727B2 (en) Charging device using a charge roller and image forming apparatus including the same
US7603063B2 (en) Method and apparatus for electro photographic image forming capable of effectively performing an evenly charging operation
JP5338480B2 (en) Image forming apparatus
JP4934512B2 (en) Image forming apparatus and process cartridge
US8121527B2 (en) Image forming apparatus having a neutralizing member of determined resistivity
US20070297830A1 (en) Image forming apparatus and process cartridge
JP5305154B2 (en) Image forming apparatus
CN101320238B (en) Electrifying device, process cartridge and image forming apparatus
JP4146266B2 (en) Charging device and image forming apparatus
JP4420784B2 (en) Image forming apparatus and process cartridge
JP2008107571A (en) Image forming apparatus and process cartridge
US8081913B2 (en) Image forming apparatus
JP5370534B2 (en) Lubricant coating apparatus, process cartridge, and image forming apparatus
JP2006098728A (en) Image forming apparatus
JP4393964B2 (en) Charging roller manufacturing method
JP2004258064A (en) Electrifying device and image forming apparatus
JP2006085033A (en) Latent image bearing member and image forming apparatus
JP2010276822A (en) Image forming apparatus
JP2006106563A (en) Process unit, image forming apparatus and rotating member manufacturing method
JP2011186013A (en) Image forming apparatus
JP2004198621A (en) Charging device and image forming apparatus

Legal Events

Date Code Title Description
C06 Publication
PB01 Publication
C10 Entry into substantive examination
SE01 Entry into force of request for substantive examination
C14 Grant of patent or utility model
GR01 Patent grant
CF01 Termination of patent right due to non-payment of annual fee

Granted publication date: 20120321

Termination date: 20190110

CF01 Termination of patent right due to non-payment of annual fee