Abstract:
In an image reading apparatus, the linear coefficients of expansion of conveyance drive rollers and a linear coefficient of expansion of the holding unit are determined such that the amount of change in the outer diameter of each of the conveyance drive rollers due to a change in temperature environment is substantially the same as the amount of change in the interval between the first reading unit and the second reading unit due to a change in the temperature environment. The conveyance drive rollers are attached to a rotary shaft such that the positions of head portions of screws are alternately located along the axis direction of the rotary shaft on opposite sides of the outer circumference surface in a direction perpendicular to the axis direction of the rotary shaft.
Abstract:
The invention provides, as an aspect thereof, an document reading apparatus that includes: a speed calculating unit that calculates a speed related to the rotation of a motor on the basis of a signal that is outputted from an encoder; and a controlling unit that calculates control amount on the basis of the speed calculated by the speed calculating unit so as to control the rotation of the motor in accordance with the calculated control amount. In the configuration of an document reading apparatus according to this aspect of the invention, the above-mentioned controlling unit controls the motor with an increase in the control amount in a case where there occurs no change in the signal that is outputted from the encoder for a certain period of time. The increase in the control amount is based on the length of time that has elapsed since the last change in the signal.
Abstract:
An optical scanning device includes a light source, an optical system, and a housing. The light source projects a light beam. The housing includes a holder and encloses the optical system. The optical system includes a liquid crystal element held by the housing via the holder, to modulate a phase of the light beam projected from the light source against a scanned surface. The liquid crystal element includes a plurality of substantially transparent substrates, a liquid crystal layer, and a sealing member. One of the plurality of the transparent substrates has a size larger than any other transparent substrates and is positioned in the holder. The liquid crystal layer is sandwiched between the plurality of substantially transparent substrates. The sealing member seals the liquid crystal layer between the plurality of substantially transparent substrates.
Abstract:
Disclosed herein is a method of controlling a motor in an image reading apparatus. It may be possible to optimize the drive current of the motor for driving the movement of the scanning module by using information associated with, for example, the time it takes for the scanning module to return to a home or rest position after the scanning module is moved from the home position to a predetermined position. Such optimized drive current can result in improvements in the reading performance of an image by the image reading apparatus and reduction of power consumption.
Abstract:
In an image reading apparatus, a plurality of reading sensors extend in a main scanning direction and separated from each other in the main scanning direction so as to be located in a staggered arrangement in which a part of one of the reading sensors in the longitudinal direction faces a part of adjacent one of the reading sensors in a sub-scanning direction. A first connection member is provided to the part of one of the reading sensors facing the part of the adjacent one of the reading sensors. The first connection member protrudes toward the adjacent one of the reading sensors. A second connection member is provided to the part of the adjacent one of the reading sensors facing the part of the one of the reading sensors. The second connection member protrudes toward the one of the reading sensors. The first and second connection members are brought into contact with each other by being urged by a spring.
Abstract:
There is described an apparatus, which includes an image-forming section to form a multicolor image on a recording medium by recording the unicolor images in such a manner that the unicolor images overlap each other, based on printing image data sets of them, and a controlling section that determines at least a sub-scanning velocity in a sub-scanning direction relative to the recording medium, corresponding to a printing magnification factor, so as to adjust an output-start timing in the sub-scanning direction for every printing image data set, in response to the sub-scanning velocity determined in advance. Further, the controlling section also determines a main-scanning velocity in a main-scanning direction, corresponding to the printing magnification factor, so as to adjust output-start timings in both the main-scanning direction and the sub-scanning direction for every printing image data set, in response to the main-scanning velocity and the sub-scanning velocity, both determined in advance.
Abstract:
An image forming apparatus includes a plurality of image forming stations each having an image carrier and forming an image on the image carrier; a mark detecting unit for detecting a plurality of registration correction marks formed on a recording medium by the plurality of image forming stations; a correction mechanism for correcting a position difference between images formed by the plurality of image forming stations in accordance with a detection result by the mark detecting unit; and a controller for independently controlling an image forming operation of each of the plurality of the image forming stations so that the image density of each of the registration correction marks formed by the plurality of image forming units has a different predetermined image density.
Abstract:
An image reading device reads an image of an original mounted on an original mounting base by using an optical scanning unit which is subjected to acceleration drive along the original mounting base until a velocity according to a reading magnification is obtained and then scanned by uniform velocity drive. A stepping motor moves the optical scanning unit. A reading magnification acceptance portion accepts a reading magnification of an image of the original mounted on the original mounting base. A motor drive control portion is used for control a drive electric current of the stepping motor, obliquely increases a set electric current during acceleration drive every velocity that the optical scanning unit reaches by a pulse number according to a reading magnification accepted by the reading magnification acceptance portion, and changes the set electric current value in accordance with the reading magnification so as to provide a characteristic for lowering the set electric current value at the time of shifting to uniform velocity drive. A photoelectric conversion portion converts a quantity of reflected light when the original on the original mounting base is optically scanned by the optical scanning unit moved by the stepping motor into an electrical signal.
Abstract:
In an image reading apparatus, a plurality of reading sensors extend in a main scanning direction and separated from each other in the main scanning direction so as to be located in a staggered arrangement in which a part of one of the reading sensors in the longitudinal direction faces a part of adjacent one of the reading sensors in a sub-scanning direction. A first connection member is provided to the part of one of the reading sensors facing the part of the adjacent one of the reading sensors. The first connection member protrudes toward the adjacent one of the reading sensors. A second connection member is provided to the part of the adjacent one of the reading sensors facing the part of the one of the reading sensors. The second connection member protrudes toward the one of the reading sensors. The first and second connection members are brought into contact with each other by being urged by a spring.
Abstract:
The image recording method and apparatus deflect light from a group of two-dimensionally disposed light source elements to move an image formed on a recording medium in accordance with a movement of the recording medium, or shift modulation data of the group of two-dimensionally disposed light source elements in a first moving direction of the recording medium on the group of two-dimensionally disposed light source elements in synchronism with the movement of the recording medium, and thereby have the image remain stationary relatively to the recording medium in the main scanning direction, as well as shift sequentially modulation data of the group of two-dimensionally disposed light source elements in a direction opposite to a second moving direction of the optical system in synchronism with a movement of the optical system in the auxiliary scanning direction, and thereby having the image also remain stationary relatively to the recording medium in the auxiliary scanning direction.