Image forming apparatus
AssigneeRicoh Company, Ltd.
InventorsHidetoshi KAMI, Hiroki ORII, Ryohta TAKAHASHI
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Abstract
Provided is an image forming apparatus including an image bearer capable of bearing a toner image, where a latent image is formed on the image bearer, a developing unit configured to develop the latent image formed on the image bearer with a toner, and a cleaning unit including a blade-shaped elastic body, where the elastic body is brought into contact with a surface of the image bearer, wherein a friction coefficient Ft/Fn between the image bearer and the elastic body is 0.85 or greater but 1.1 or less, and self-excited vibration WRFt(LMH) of shear force of the elastic body in a LMH band is 1.5 gf or greater but 3.5 gf or less.
Claims6
An image forming apparatus comprising:
- an image bearer capable of bearing a toner image, where a latent image is formed on the image bearer;
- a developing unit configured to develop the latent image formed on the image bearer with a toner;
- and
- a cleaning unit including a blade-shaped elastic body, where the elastic body is brought into contact with a surface of the image bearer,
- wherein a friction coefficient Ft/Fn between the image bearer and the elastic body is 0.85 or greater but 1.1 or less, and
- wherein a size WRFt(LMH) of self-excited vibration of shear force of the elastic body in a LMH band as determined by a method described in (i) to (v) below is 1.5 gf or greater but 3.5 gf or less:
- (i) generating waveform data WFt of a time change of shear force generated in the elastic body due to frictions with the image bearer;
- (ii) performing a multiresolution analysis to transform the waveform data WFt through wavelet transformation to separate the waveform data WFt into 6 frequency components (HHH, HHL, HMH, HML, HLH, and HLL) of the waveform data of shear force ranging from a high frequency component to a low frequency component;
- (iii) generating waveform data of shear force through decimation performed on the lowest frequency component of the waveform data WFt(HLL) of shear force among the obtained 6 frequency components in a manner that a sampling number is reduced to 1/40;
- (iv) further performing a multiresolution analysis to transform the generated waveform data through wavelet transformation to separate the waveform data into additional 6 frequency components (LHH, LHL, LMH, LML, LLH, and LLL) of the waveform data of shear force ranging from a high frequency component to a low frequency component;
- and
- (v) determining self-excited vibration WRFt(LMH) of shear force of the elastic body in the LMH band from the waveform data WFt(LMH) of shear force in the LMH band obtained in (iv) according to Formula (1),
- WRFt
-
- (
- LMH
- )
- =
- 1
- L
-
- ∫
- 0
- L
-
-
- WFt
-
- [
- LHM
- ]
-
- (
- x
- )
-
-
- dx
- Formula
-
-
- (
- 1
- )
- (L:
- a duration of the entire measurement, x:
- time, WFt[LMH](x):
- waveform data of a time change of shear force in the LMH band) where each frequency band satisfies a relationship below:
- TABLE 1
- Abbrevia-
- Median of
- Median of
- tions of
- Duration
- Frequency
- duration
- frequency
- frequency
- of 1 cycle
- band
- of 1 cycle
- band
- bands
- [msec]
- [Hz]
- [msec]
- [Hz]
- HHH
- 0.0 to 3.8
- 260.4 to ∞
- 1.9
- 520.8
- HHL
- 1.3 to 7.7
- 130.2 to 781.3
- 4.5
- 223.2
- HMH
- 2.6 to 16.6
- 60.1 to 390.6
- 9.6
- 104.2
- HML
- 5.1 to 32
- 31.3 to 195.3
- 18.6
- 53.9
- HLH
- 12.8 to 64
- 15.6 to 78.1
- 38.4
- 26
- HLL
- 30.7 to 126.7
- 7.9 to 32.6
- 78.7
- 12.7
- LHH
- 33.3 to 135.7
- 7.4 to 30
- 84.5
- 11.8
- LHL
- 67.8 to 234.2
- 4.3 to 14.7
- 151
- 6.6
- LMH
- 135.7 to 407
- 2.5 to 7.4
- 271.4
- 3.7
- LML
- 273.9 to 705.3
- 1.4 to 3.7
- 489.6
- 2
- LLH
- 551.7 to 1221.1
- 0.8 to 1.8
- 886.4
- 1.1
- LLL
- 1109.8 to 2117.1
- 0.5 to 0.9
- 1613.4
- 0.6.
Dependencies are inferred from the claim text.