US5420671A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Charger and image forming apparatus with same
Assignee: Canon Inc
•
Filing: 1994-02-15
•
Granted: 1995-05-30
•
Expires: 2014-02-15
Abstract
Abstract A charging device contactable to a member in order to charge it electrically. The voltage of the charging member includes an AC component. A controller controls the AC component so as to be a constant current, by which the member to be charged can be stably and uniformly charged even if ambient conditions change.
Inventors
- 👤 Hiroki Kisu
- 👤 Toshio Miyamoto
- 👤 Yohji Tomoyuki
- 👤 Junji Araya
- 👤 Shunji Nakamura
- 👤 Masanobu Saito
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 18:57
CPC Classifications
G; G03; G03G; G03G13/00; G03G15/00; G03G15/02; G03G15/0208; G03G15/0216; G03G15/0266
Claims Analysis
Total Claims: 99
Claim 1
Independent Claim
122 words
An image forming apparatus, comprising: a movable image bearing member; image forming means for forming an image on said image bearing member, said image forming means including latent image forming means for forming a latent image having charging means contactable to said image bearing member for directly charging said image bearing member, and developing means for developing the latent image with toner; voltage application means for applying a voltage having a periodically vibrating component and a DC component between said charging means and said image bearing member; and control means for controlling the vibrating component applied to said charging means by said voltage application means to a constant current during the formation of the latent image by said latent image forming means.
Claim 2
Dependent Claim
122 words
An image forming apparatus, comprising: a movable image bearing member; image forming means for forming an image on said image bearing member, said image forming means including latent image forming means for forming a latent image having charging means contactable to said image bearing member for directly charging said image bearing member, and developing means for developing the latent image with toner; voltage application means for applying a voltage having a periodically vibrating component and a DC component between said charging means and said image bearing member; and control means for controlling the vibrating component applied to said charging means by said voltage application means to a constant current during the formation of the latent image by said latent image forming means.
Claim 3
Dependent Claim
33 words
An apparatus according to claim 1, wherein said apparatus further comprises second control means for controlling the DC component applied to the charging means by said voltage application means to a constant voltage.
Claim 4
Dependent Claim
18 words
An apparatus according to claim 1, wherein the vibrating component is in the form of a sine wave.
Claim 5
Dependent Claim
18 words
An apparatus according to claim 1, wherein the vibrating component is in the form of a triangular wave.
Claim 6
Dependent Claim
18 words
An apparatus according to claim 1, wherein the vibrating component is in the form of a rectangular wave.
Claim 7
Dependent Claim
39 words
An apparatus according to claim 1, wherein the voltage applied to the charging means includes the vibrating component which has a peak-to-peak voltage larger than twice an absolute value of a charge starting voltage applied to said charging means.
Claim 8
Dependent Claim
13 words
An apparatus according to claim 1, wherein said charging means includes a roller.
Claim 9
Dependent Claim
13 words
An apparatus according to claim 1, wherein said charging means includes a blade.
Claim 10
Dependent Claim
15 words
An apparatus according to claim 1, wherein said image bearing member is a photosensitive member.
Claim 11
Dependent Claim
38 words
An apparatus according to claim 1, wherein a polarity to which said image bearing member is charged by said charging means is the same as a polarity of the charge of the toner supplied by said developing means.
Claim 12
Dependent Claim
52 words
An apparatus according to claim 9, wherein said latent image forming means includes exposure means for exposing to light a surface of said image bearing member having been charged by said charging means, and said exposure means applies to said image bearing member light corresponding to a signal indicative of image information.
Claim 13
Dependent Claim
15 words
An apparatus according to claim 11, wherein said exposure means includes a laser beam scanner.
Claim 14
Dependent Claim
26 words
An apparatus according to claim 1, further comprising a process cartridge detachably mounted thereto, said processing cartridge containing said image bearing member and said charging means.
Claim 15
Dependent Claim
19 words
An apparatus according to claim 13, wherein said process cartridge further contains developing means for developing the latent image.
Claim 16
Dependent Claim
41 words
An apparatus according to claim 1, wherein said charging means includes a core member, a conductive layer, and a resistance layer having a volume resistivity higher than that of said conductive layer, in the order named toward said image bearing member.
Claim 17
Dependent Claim
20 words
An apparatus according to claim 1 or 15, wherein said charging means has an impedance which changes with ambient condition.
Claim 18
Dependent Claim
15 words
An apparatus according to claim 16, wherein the ambient condition includes ambient temperature and humidity.
Claim 19
Dependent Claim
16 words
An apparatus according to claim 1, wherein said vibrating component is in the form of pulses.
Claim 20
Dependent Claim
16 words
An apparatus according to claim 9, wherein said image bearing member is of amorphous silicon photoconductor.
Claim 21
Dependent Claim
16 words
An apparatus according to claim 9, wherein said image bearing member is of an organic photoconductor.
Claim 22
Dependent Claim
28 words
An apparatus according to claim 1, wherein said apparatus has a process cartridge having said image bearing member, said charging means, and said developing means as a unit.
Claim 23
Dependent Claim
29 words
An apparatus according to claim 1, wherein said control means controls the voltage having a peak-to-peak voltage level which increases with increase of an impedance of said charging means.
Claim 24
Dependent Claim
167 words
An image forming apparatus, comprising: a movable image bearing member; image forming means for forming an image on said image bearing member, said image forming means including latent image forming means for forming a latent image, having charging means contactable to said image bearing member for directly charging said image bearing member, and developing means for developing the latent image with toner; voltage application means for applying a voltage having a periodically vibrating component and a DC component between said charging means and the image bearing member; and control means for controlling said voltage application means so that the voltage has a first peak-to-peak voltage level when said charging means has a first impedance and that the voltage has a second peak-to-peak voltage which is larger than the first voltage level when said charging means has a second impedance which is higher than the first impedance, said control means controls the voltage application means during the formation of the latent image by said latent image forming means.
Claim 25
Dependent Claim
167 words
An image forming apparatus, comprising: a movable image bearing member; image forming means for forming an image on said image bearing member, said image forming means including latent image forming means for forming a latent image, having charging means contactable to said image bearing member for directly charging said image bearing member, and developing means for developing the latent image with toner; voltage application means for applying a voltage having a periodically vibrating component and a DC component between said charging means and the image bearing member; and control means for controlling said voltage application means so that the voltage has a first peak-to-peak voltage level when said charging means has a first impedance and that the voltage has a second peak-to-peak voltage which is larger than the first voltage level when said charging means has a second impedance which is higher than the first impedance, said control means controls the voltage application means during the formation of the latent image by said latent image forming means.
Claim 26
Dependent Claim
29 words
An apparatus according to claim 23, wherein said control means controls the voltage having a peak-to-peak voltage level which increases with increase of an impedance of said charging means.
Claim 27
Dependent Claim
33 words
An apparatus according to claim 23, wherein said apparatus further comprises second control means for controlling the DC component applied to the charging means by said voltage application means to a constant voltage.
Claim 28
Dependent Claim
18 words
An apparatus according to claim 23, wherein the vibrating component is in the form of a sine wave.
Claim 29
Dependent Claim
39 words
An apparatus according to claim 23, wherein the voltage applied to the charging means includes the vibrating component which has a peak-to-peak voltage larger than twice an absolute value of a charge starting voltage to the image bearing member.
Claim 30
Dependent Claim
13 words
An apparatus according to claim 23, when said charging means includes a roller.
Claim 31
Dependent Claim
13 words
An apparatus according to claim 23, wherein said charging means includes a blade.
Claim 32
Dependent Claim
15 words
An apparatus according to claim 23, wherein the image bearing member is a photosensitive member.
Claim 33
Dependent Claim
41 words
An apparatus according to claim 23, wherein said charging means includes a core member, a conductive layer, and a resistance layer having a volume resistivity higher than that of said conductive layer, in the order named toward said image bearing member.
Claim 34
Dependent Claim
20 words
An apparatus according to claim 23 or 31, wherein said charging means has an impedance which changes with ambient condition.
Claim 35
Dependent Claim
15 words
An apparatus according to claim 32, wherein the ambient condition includes ambient temperature and humidity.
Claim 36
Dependent Claim
16 words
An apparatus according to claim 23, wherein said vibrating component is in the form of pulses.
Claim 37
Dependent Claim
28 words
An apparatus according to claim 22, further comprising a process cartridge detachably mounted thereto, and wherein said process cartridge contains said image bearing member and said charging means.
Claim 38
Dependent Claim
19 words
An apparatus according to claim 35, wherein said process cartridge further contains developing means for developing the latent image.
Claim 39
Independent Claim
41 words
An apparatus according to any one of claims 6 or 27, wherein the vibratory component has a peak-to-peak voltage not less than twice an absolute value of the charge starting voltage irrespective of change of an impedance of said charging means.
Claim 40
Dependent Claim
102 words
An image forming apparatus, comprising: a movable image bearing member; image forming means for forming an image on said image bearing member, said image forming means including latent image forming means for forming a latent image, wherein said latent image forming means includes charging means contactable to said image bearing member to charge said image bearing member; voltage application means for applying a voltage having a vibrating component between said charging means and said image bearing member; and control means for controlling the vibrating component to a constant current during the formation of the latent image by said latent image forming means.
Claim 41
Dependent Claim
102 words
An image forming apparatus, comprising: a movable image bearing member; image forming means for forming an image on said image bearing member, said image forming means including latent image forming means for forming a latent image, wherein said latent image forming means includes charging means contactable to said image bearing member to charge said image bearing member; voltage application means for applying a voltage having a vibrating component between said charging means and said image bearing member; and control means for controlling the vibrating component to a constant current during the formation of the latent image by said latent image forming means.
Claim 42
Dependent Claim
40 words
An apparatus according to claim 38, wherein the voltage has a non-vibrating component, and said apparatus further comprises second control means for controlling the non-vibrating component applied to the charging means by said voltage application means to a constant voltage.
Claim 43
Dependent Claim
18 words
An apparatus according to claim 38, wherein the vibrating component is in the form of a sine wave.
Claim 44
Dependent Claim
18 words
An apparatus according to claim 38, wherein the vibrating component is in the form of a rectangular wave.
Claim 45
Dependent Claim
30 words
An apparatus according to claim 38, wherein the vibrating component has a peak-to-peak voltage larger than twice an absolute value of a charge starting voltage applied to said charging means.
Claim 46
Dependent Claim
17 words
An apparatus according to claim 38, wherein said charging means is in the form of a roller.
Claim 47
Dependent Claim
17 words
An apparatus according to claim 38, wherein said charging means is in the form of a blade.
Claim 48
Dependent Claim
15 words
An apparatus according to claim 38, wherein said image bearing member is a photosensitive member.
Claim 49
Dependent Claim
51 words
An apparatus according to claim 38, wherein said apparatus comprises developing means for developing the latent image with toner, wherein a polarity to which said image bearing member is charged by said charging means is the same as a polarity of the charge of the toner supplied to said developing means.
Claim 50
Dependent Claim
29 words
An apparatus according to claim 46, further comprising a process cartridge detachably mounted thereto, said processing cartridge containing said image bearing member, said charging means, and said developing means.
Claim 51
Dependent Claim
41 words
An apparatus according to claim 38, wherein said charging means includes a core member, a conductive layer, and a resistance layer having a volume resistivity higher than that of said conductive layer, in the order named toward said image bearing member.
Claim 52
Dependent Claim
31 words
An apparatus according to claim 38, wherein said apparatus has a process cartridge detachably mountable to said apparatus, and said process cartridge contains said image bearing member and said charging member.
Claim 53
Dependent Claim
29 words
An apparatus according to claim 38, wherein said control means controls the voltage having a peak-to-peak voltage level with increases with increase of an impedance of said charging means.
Claim 54
Dependent Claim
24 words
An apparatus according to claim 38, wherein a waveform of the vibrating component remains unchanged despite change of the impedance of said charging means.
Claim 55
Dependent Claim
157 words
An image forming apparatus, comprising: a movable image bearing member; image forming means for forming an image on said image bearing member, said image forming means including latent image forming means for forming a latent image, wherein said latent image forming means includes charging means contactable to said image bearing member to charge said image bearing member; voltage application means for applying a voltage having a vibrating component between said charging means and the image bearing member; and control means for controlling said voltage application means so that the voltage has a first peak-to-peak voltage level when said charging means has a first impedance and that the voltage has a second peak-to-peak voltage which is larger than the first voltage level when said charging means has a second impedance which is higher than the first impedance, said control means controls the voltage application means during the formation of the latent image by said latent image forming means.
Claim 56
Dependent Claim
157 words
An image forming apparatus, comprising: a movable image bearing member; image forming means for forming an image on said image bearing member, said image forming means including latent image forming means for forming a latent image, wherein said latent image forming means includes charging means contactable to said image bearing member to charge said image bearing member; voltage application means for applying a voltage having a vibrating component between said charging means and the image bearing member; and control means for controlling said voltage application means so that the voltage has a first peak-to-peak voltage level when said charging means has a first impedance and that the voltage has a second peak-to-peak voltage which is larger than the first voltage level when said charging means has a second impedance which is higher than the first impedance, said control means controls the voltage application means during the formation of the latent image by said latent image forming means.
Claim 57
Dependent Claim
40 words
An apparatus according to claim 52, wherein the voltage has a non-vibrating component, and said apparatus further comprises second control means for controlling the non-vibrating component applied to the charging means by said voltage application means to a constant voltage.
Claim 58
Dependent Claim
18 words
An apparatus according to claim 52, wherein the vibrating component is in the form of a sine wave.
Claim 59
Dependent Claim
18 words
An apparatus according to claim 52, wherein the vibrating component is in the form of a rectangular wave.
Claim 60
Dependent Claim
30 words
An apparatus according to claim 52, wherein the vibrating component has a peak-to-peak voltage larger than twice an absolute value of a charge starting voltage applied to said charging means.
Claim 61
Dependent Claim
17 words
An apparatus according to claim 52, wherein said charging means is in the form of a roller.
Claim 62
Dependent Claim
17 words
An apparatus according to claim 52, wherein said charging means is in the form of a blade.
Claim 63
Dependent Claim
15 words
An apparatus according to claim 52, wherein said image bearing member is a photosensitive member.
Claim 64
Dependent Claim
51 words
An apparatus according to claim 52, wherein said apparatus comprises developing means for developing the latent image with toner, wherein a polarity to which said image bearing member is charged by said charging means is the same as a polarity of the charge of the toner supplied to said developing means.
Claim 65
Dependent Claim
29 words
An apparatus according to claim 60, further comprising a process cartridge detachably mounted thereto, said processing cartridge containing said image bearing member, said charging means, and said developing means.
Claim 66
Dependent Claim
41 words
An apparatus according to claim 52, wherein said charging means includes a core member, a conductive layer, and a resistance layer having a volume resistivity higher than that of said conductive layer, in the order named toward said image bearing member.
Claim 67
Dependent Claim
31 words
An apparatus according to claim 52, wherein said apparatus has a process cartridge detachably mountable to said apparatus, and said process cartridge contains said image bearing member and said charging member.
Claim 68
Dependent Claim
29 words
An apparatus according to claim 52, wherein said control means controls the voltage having a peak-to-peak voltage level with increases with increase of an impedance of said charging means.
Claim 69
Dependent Claim
24 words
An apparatus according to claim 52, wherein a waveform of the vibrating component remains unchanged despite change of the impedance of said charging means.
Claim 70
Dependent Claim
126 words
An image forming apparatus, comprising: a movable image bearing member; image forming means for forming an image on said image bearing member, said image forming means including latent image forming means for forming a latent image, wherein said latent image forming means includes charging means contactable to said image bearing member, for charging said image bearing member, at a portion of the image bearing member which is adjacent to a contact portion between said charging member and said image bearing member; voltage application means for applying a voltage having a vibrating component between said charging means and said image bearing member; and control means for controlling the vibrating component to a constant current during the formation of the latent image by said latent image forming means.
Claim 71
Dependent Claim
126 words
An image forming apparatus, comprising: a movable image bearing member; image forming means for forming an image on said image bearing member, said image forming means including latent image forming means for forming a latent image, wherein said latent image forming means includes charging means contactable to said image bearing member, for charging said image bearing member, at a portion of the image bearing member which is adjacent to a contact portion between said charging member and said image bearing member; voltage application means for applying a voltage having a vibrating component between said charging means and said image bearing member; and control means for controlling the vibrating component to a constant current during the formation of the latent image by said latent image forming means.
Claim 72
Dependent Claim
40 words
An apparatus according to claim 66, wherein the voltage has a non-vibrating component, and said apparatus further comprises second control means for controlling the non-vibrating component applied to the charging means by said voltage application means to a constant voltage.
Claim 73
Dependent Claim
18 words
An apparatus according to claim 66, wherein the vibrating component is in the form of a sine wave.
Claim 74
Dependent Claim
18 words
An apparatus according to claim 66, wherein the vibrating component is in the form of a rectangular wave.
Claim 75
Dependent Claim
30 words
An apparatus according to claim 66, wherein the vibrating component has a peak-to-peak voltage larger than twice an absolute value of a charge starting voltage applied to said charging means.
Claim 76
Dependent Claim
17 words
An apparatus according to claim 66, wherein said charging means is in the form of a roller.
Claim 77
Dependent Claim
17 words
An apparatus according to claim 66, wherein said charging means is in the form of a blade.
Claim 78
Dependent Claim
15 words
An apparatus according to claim 66, wherein said image bearing member is a photosensitive member.
Claim 79
Dependent Claim
51 words
An apparatus according to claim 66, wherein said apparatus comprises developing means for developing the latent image with toner, wherein a polarity to which said image bearing member is charged by said charging means is the same as a polarity of the charge of the toner supplied to said developing means.
Claim 80
Dependent Claim
29 words
An apparatus according to claim 74, further comprising a process cartridge detachably mounted thereto, said processing cartridge containing said image bearing member, said charging means, and said developing means.
Claim 81
Dependent Claim
41 words
An apparatus according to claim 66, wherein said charging means includes a core member, a conductive layer, and a resistance layer having a volume resistivity higher than that of said conductive layer, in the order named toward said image bearing member.
Claim 82
Dependent Claim
31 words
An apparatus according to claim 66, wherein said apparatus has a process cartridge detachably mountable to said apparatus, and said process cartridge contains said image bearing member and said charging member.
Claim 83
Dependent Claim
29 words
An apparatus according to claim 66, wherein said control means controls the voltage having a peak-to-peak voltage level with increases with increase of an impedance of said charging means.
Claim 84
Dependent Claim
24 words
An apparatus according to claim 66, wherein a waveform of the vibrating component remains unchanged despite change of the impedance of said charging means.
Claim 85
Dependent Claim
181 words
An image forming apparatus, comprising: a movable image bearing member; image forming means for forming an image on said image bearing member, said image forming means including latent image forming means for forming to latent image, wherein said latent image forming means includes charging means, contactable to said image bearing member, for charging said image bearing member at a portion of the image bearing member which is adjacent to a contact portion between said charging member and said image bearing member; voltage application means for applying a voltage having a vibrating component between said charging means and the image bearing member; and control means for controlling said voltage application means so that the voltage has a first peak-to-peak voltage level when said charging means has a first impedance and that the voltage has a second peak-to-peak voltage which is larger than the first voltage level when said charging means has a second impedance which is higher than the first impedance, said control means controls the voltage application means during the formation of the latent image by said latent image forming means.
Claim 86
Dependent Claim
181 words
An image forming apparatus, comprising: a movable image bearing member; image forming means for forming an image on said image bearing member, said image forming means including latent image forming means for forming to latent image, wherein said latent image forming means includes charging means, contactable to said image bearing member, for charging said image bearing member at a portion of the image bearing member which is adjacent to a contact portion between said charging member and said image bearing member; voltage application means for applying a voltage having a vibrating component between said charging means and the image bearing member; and control means for controlling said voltage application means so that the voltage has a first peak-to-peak voltage level when said charging means has a first impedance and that the voltage has a second peak-to-peak voltage which is larger than the first voltage level when said charging means has a second impedance which is higher than the first impedance, said control means controls the voltage application means during the formation of the latent image by said latent image forming means.
Claim 87
Dependent Claim
40 words
An apparatus according to claim 80, wherein the voltage has a non-vibrating component, and said apparatus further comprises second control means for controlling the non-vibrating component applied to the charging means by said voltage application means to a constant voltage.
Claim 88
Dependent Claim
18 words
An apparatus according to claim 80, wherein the vibrating component is in the form of a sine wave.
Claim 89
Dependent Claim
18 words
An apparatus according to claim 80, wherein the vibrating component is in the form of a rectangular wave.
Claim 90
Dependent Claim
30 words
An apparatus according to claim 80, wherein the vibrating component has a peak-to-peak voltage larger than twice an absolute value of a charge starting voltage applied to said charging means.
Claim 91
Dependent Claim
17 words
An apparatus according to claim 80, wherein said charging means is in the form of a roller.
Claim 92
Dependent Claim
17 words
An apparatus according to claim 80, wherein said charging means is in the form of a blade.
Claim 93
Dependent Claim
15 words
An apparatus according to claim 80, wherein said image bearing member is a photosensitive member.
Claim 94
Dependent Claim
51 words
An apparatus according to claim 80, wherein said apparatus comprises developing means for developing the latent image with toner, wherein a polarity to which said image bearing member is charged by said charging means is the same as a polarity of the charge of the toner supplied to said developing means.
Claim 95
Dependent Claim
29 words
An apparatus according to claim 88, further comprising a process cartridge detachably mounted thereto, said processing cartridge containing said image bearing member, said charging means, and said developing means.
Claim 96
Dependent Claim
41 words
An apparatus according to claim 80, wherein said charging means includes a core member, a conductive layer, and a resistance layer having a volume resistivity higher than that of said conductive layer, in the order named toward said image bearing member.
Claim 97
Dependent Claim
31 words
An apparatus according to claim 80, wherein said apparatus has a process cartridge detachably mountable to said apparatus, and said process cartridge contains said image bearing member and said charging member.
Claim 98
Dependent Claim
29 words
An apparatus according to claim 80, wherein said control means controls the voltage having a peak-to-peak voltage level with increases with increase of an impedance of said charging means.
Claim 99
Dependent Claim
24 words
An apparatus according to claim 80, wherein a waveform of the vibrating component remains unchanged despite change of the impedance of said charging means.
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