Patents by Inventor Yutaka Koizumi
Yutaka Koizumi has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
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Patent number: 4908636Abstract: A liquid jet recording apparatus includes a cap member for covering discharge ports of a liquid jet recording head which discharge recording liquid. The cap member is provided with a protruding portion opposed to the discharge ports. Gas flow is generated in a space formed by the cap member and the liquid jet recording head. The protruding portion provides for a negative or reduced pressure at the discharge ports, to draw off impurities and improve recovery. An improved recovery method is also provided.Type: GrantFiled: March 21, 1988Date of Patent: March 13, 1990Assignee: Canon Kabushiki KaishaInventors: Atsushi Saito, Yutaka Koizumi, Toshihiro Mori, Minoru Nozawa
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Patent number: 4896172Abstract: A liquid injection recording apparatus comprises a recording head having discharge ports for discharging recording liquid therethrough, a liquid path communicating with the discharge ports, a liquid chamber communicating with the liquid path and energy generating elements utilized for discharging the recording liquid, a temperature sensor for detecting the temperature of the recording head and/or the recording liquid in the recording head, a storing tank for storing the recording liquid to be supplied to the recording head, a communicating path for switchably communicating between a supply system for supplying the recording liquid from the storing tank to the liquid chamber and a circulation system for circulating the recording liquid between the storing tank and the liquid chamber, a switching device for switching the communicating path to either of the supply system or the circulation system in accordance with temperature information from the temperature sensor, and a control circuit for controlling the swiType: GrantFiled: November 16, 1988Date of Patent: January 23, 1990Assignee: Canon Kabushiki KaishaInventors: Minoru Nozawa, Yutaka Koizumi, Toshihiro Mori, Atsushi Saito
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Patent number: 4843292Abstract: A direct drive motor system for controlling driving of the joints of a multi-jointed robot, comprising a motor portion, a rotation detecting portion, a position control portion, a speed control portion, a driving circuit and a tuning portion, wherein the motor portion is of an inductor type, the rotation detection portion uses an optical rotary encoder or magnetic resolver, and the position control portion is arranged to control in a feedback manner the rotational position of the motor with a tertiary servo system with software. The system's driving circuit has a feedback control loop for the current of the motor coil, and a detection circuit for the current includes a small signal isolator. The tuning portion tunes the servo systems of the speed control portion and the position control portion. As a result, the system simultaneously satisfies various requirements of such a direct drive motor.Type: GrantFiled: February 25, 1999Date of Patent: June 27, 1989Assignee: Yokogawa Electric CorporationInventors: Yutaka Ono, Yayoi Tsuchiya, Yutaka Koizumi, Hitoshi Morimoto, Hideo Banzai, Yasuhiko Muramatsu, Syotoro Shindo, Toshihiro Kanehara, Norihiko Hatano, Susumu Ohta, Mitsuhiro Nikaido
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Patent number: 4772253Abstract: A wide seamless endless belt. A belt comprising a wide seamless endless-belt-like sheet metal 10 to 50 .mu.m, and a lining layer made of flexible material provided on the inside surface thereof and carrying a mechanical force required for belt. This endless belt is used as a substrate of a photosensitive belt for an electrostatic photographic copying machine.Type: GrantFiled: April 9, 1987Date of Patent: September 20, 1988Assignee: Ricoh Company, Ltd.Inventors: Yutaka Koizumi, Hidetoshi Yano, Hideki Akiyoshi
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Patent number: 4751549Abstract: A full-color copying machine copying color originals in colors as they are. A full-color copying machine in which a photosensitive member carrying multi-colored visible images obtained based on a color original is formed into belt, and the photosensitive belt is looped over between copying process stations.Type: GrantFiled: December 19, 1986Date of Patent: June 14, 1988Assignee: Ricoh Company, Ltd.Inventor: Yutaka Koizumi
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Patent number: 4746950Abstract: A color copier scans an original carrying a multi-color image in one direction to form toner images of different color components thereof on respective photosensitive drums while moving a transfer sheet in the opposite direction to transfer in registration thereon the several toner images and thereby form a composite color image of the original without reversing the rotational direction of the drums. After the latent image on a given drum is developed with a toner of a respective color, the drum is quenched to remove residual charge by irradiating it with light of a color which is not significantly absorbed by the toner on the drum. The quenching light color differs as between different drums, and for a given drum the quenching light color differs from the color of the light used to form the latent image on that drum.Type: GrantFiled: January 8, 1986Date of Patent: May 24, 1988Assignee: Ricoh Company, Ltd.Inventors: Mitsuru Mamizuka, Hideya Furuta, Yutaka Koizumi, Yoshihiro Sakai
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Patent number: 4742371Abstract: An optical system for a color copier in which light images of blue, green and red produced by color separation are formed one on each of three photoconductive elements, then developed by toner of associated colors, and then transferred one upon another onto a paper. A first mirror is disposed in an optical path to which light representative of an image of an original document is led through an image-forming lens and a mirror group. Light reflected by the first mirror is focused onto a first photoconductive element. Light transmitted through the first mirror is split by a second mirror which is located in a position for intercepting a part of the width of a slit for exposure. Light reflected by the second mirror is focused onto a second photoconductive element. Further, light outside the range of the second mirror is reflected by a third mirror to be focused onto a third photoconductive element. The first mirror has a spectral characteristic which reflects light of one of three colors, i.e.Type: GrantFiled: May 1, 1987Date of Patent: May 3, 1988Assignee: Ricoh Company, Ltd.Inventors: Hideya Furuta, Yutaka Koizumi, Kazusige Taguchi, Yoshihiro Sakai
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Patent number: 4690542Abstract: In a color copying apparatus including a plurality of photosensitive members and a mounting table driven by a pulley, in which an original mounted on the mounting table is illuminated to expose the respective photosensitive members with reflected light from the original to thereby form latent images thereon while the mounting table travels and these images, after developed, are transferred overlappingly onto a transfer paper to produce a color copy, a distance between exposing positions for adjacent photosensitive members is an integer multiple of a peripheral length of the pulley.Type: GrantFiled: December 24, 1985Date of Patent: September 1, 1987Assignee: Ricoh Company, Ltd.Inventors: Hideya Furuta, Yutaka Koizumi, Mitsuru Mamizuka, Yoshihiro Sakai
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Patent number: 4675619Abstract: In a multiple QAM system in which a pair of quadrature-phase carrier signals is modulated by a first and a second input digital signal, each representative of N or less levels, into a quadrature-phase amplitude modulated signal having M signal points on a phase plane where M is equal to N.sup.2, a code converting unit (41) converts the digital signals according to a predetermined rule into a first and a second modulating signal for use in modulating the carrier signals with the M signal points arranged approximately at a circle of a diameter which is shorter than a diagonal of a square of a side corresponding to the N levels. In a counterpart demodulating system, a pair of demodulated signals is derived from the amplitude modulated signal and converted into reproductions of the respective digital signals according to an inverse of the predetermined rule.Type: GrantFiled: September 23, 1985Date of Patent: June 23, 1987Assignee: NEC CorporationInventors: Junichi Uchibori, Yutaka Koizumi, Toshihiko Ryu
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Patent number: 4664501Abstract: A method of and an apparatus for producing duplicates of a document in color wherein a plurality of photosensitive members in drum form are rotated in the same direction and exposed to respective color-separated optical images of the document through respective arrays of gradient-index rod lenses to form electrostatic latent images on the photosensitive members while the document is supported on a document support member and moved in the same direction as the rotation of the photosensitive drums. The electrostatic latent images on the photosensitive members are developed in different colors into visible images of different colors which are printed by transfer-printing on a sheet of support material on a transfer-printing belt moved in a direction opposite the direction of movement of the document support member for light exposure of the photosensitive members.Type: GrantFiled: December 20, 1985Date of Patent: May 12, 1987Assignee: Ricoh Company, Ltd.Inventors: Yutaka Koizumi, Hideya Furuta, Yoshihiro Sakai, Mitsuru Mamizuka, Tsukasa Adachi, Itsuo Ikeda, Katsuo Sakai
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Patent number: 4662739Abstract: In a copying apparatus which comprises a plurality of rotatable photosensitive members and an image transfer belt rotatably movable in synchronism with the photosensitive members and in which visible image formed on the photosensitive members are transferred onto a transfer paper carried by the transfer belt, a pair of sensors are arranged around the transfer belt which has a pair of marks thereon and an initiation and a termination of a preprocess are performed prior to a copying process on the basis of detections of these marks by the sensors.Type: GrantFiled: December 24, 1985Date of Patent: May 5, 1987Assignee: Ricoh Company, Ltd.Inventors: Yoshihiro Sakai, Yutaka Koizumi, Mitsuru Mamizuka, Hideya Furuta
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Patent number: 4610529Abstract: An apparatus for recording color images of an original in color including three photosensitive drums capable of rotating in the normal direction and in the reverse direction. Each photosensitive drum has an outer peripheral surface of an area and an axial length large enough to accommodate an image of the original of a maximum size to which one of three color components of an optical image of the original obtained by color separation is written and developed into toner image of one of yellow, magenta and cyan. When the photosensitive drums are rotated in the normal direction, the three color components are written and developed; when the photosensitive drums are rotated in the reverse direction, a sheet of transfer material is fed at the same velocity as the peripheral velocity of the drums in the same direction as the direction of rotation of the drums and successively brought into contact with the photosensitive drums in their transfer-printing positions, to produce a color image of the original.Type: GrantFiled: May 16, 1985Date of Patent: September 9, 1986Assignee: Ricoh Co., Ltd.Inventor: Yutaka Koizumi
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Patent number: 4592644Abstract: A copying machine includes a detachably mountable cassette which includes a photosensitive web as extending between a take-up roller and a supply roller provided in the cassette. The photosensitive web includes an imaging section which corresponds in length to transfer paper of maximum size usable in the copying machine and leading and trailing sections on both sides of the imaging section. Since the web is relatively short in length, it travels substantially at constant speed between the take-up and supply rollers so that there is no need to provide an extra device for maintaining a constant speed.Type: GrantFiled: April 16, 1984Date of Patent: June 3, 1986Assignee: Ricoh Company, Ltd.Inventor: Yutaka Koizumi
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Patent number: 4571057Abstract: A recording apparatus includes an image bearing or forming drum which is driven to rotate in a predetermined direction at constant speed. As the drum rotates, an image is formed on its peripheral surface electrostatically or electrophotographically. The image, developed or undeveloped, on the drum is then transferred to a transfer medium with the stiffness of the transfer medium being adjusted prior to the transfer. The drum has a diameter which is small enough for the transfer medium to be separated away from the drum by its own stiffness after image transfer, thereby allowing to dispose of an extra separating device and to make the whole apparatus compact in size and simple in structure.Type: GrantFiled: May 9, 1983Date of Patent: February 18, 1986Assignee: Ricoh Company, Ltd.Inventors: Yutaka Koizumi, Eiichi Akutsu
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Patent number: 4539569Abstract: An ink jet recording apparatus has an improved head plate having a plurality of recording heads, a plurality of openings corresponding to the outlet port of each recording head, and a guide groove to lead ink liquid from the openings to a discharge port, the guide groove being gradually tapered downwardly to the discharge port.Type: GrantFiled: October 20, 1983Date of Patent: September 3, 1985Assignee: Canon Kabushiki KaishaInventors: Takashi Watanabe, Masakazu Ozawa, Yutaka Koizumi, Haruyuki Matsumoto
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Patent number: 4505577Abstract: A toner powder collection device suitable for use in an electrophotographic copying machine and the like includes a transporting member such as a transporting trough defining a transporting path along which the toner powder is transported and an oscillating device for preferentially oscillating the transporting member such that the toner effectively moves along the transporting path.Type: GrantFiled: March 11, 1983Date of Patent: March 19, 1985Assignee: Ricoh Company, Ltd.Inventor: Yutaka Koizumi
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Patent number: 4487501Abstract: An original to be copied is placed in a given position. An exposure optics including a movable part is employed to focus an optical image of slitwise segment of the original on a photosensitive member. The photosensitive member moves in a given direction and at a given speed throughout the exposure. The location where the image of slitwise segment of the original is focused moves through the space of the arrangement at a given speed and in a direction opposite from the direction of movement of the photosensitive member throughout the exposure. Consequently, the location corresponding to the initiation of the exposure is situated downstream as viewed in the direction of movement of the surface of the photosensitive member while the location corresponding to the end of the exposure is situated upstream as viewed in the same direction.Type: GrantFiled: June 1, 1982Date of Patent: December 11, 1984Assignee: Ricoh Company, Ltd.Inventors: Shigeru Suzuki, Yutaka Koizumi, Nobuyuki Yanagawa, Koji Hirakura, Chikara Imai
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Patent number: 4348098Abstract: An electrophotographic apparatus is provided in which a toner image formed on a photosensitive member is initially transferred onto the surface of a transfer roller and then transferred onto a transfer sheet. Before the transfer step takes place, charge is injected into the toner image on the photosensitive member and the transfer roller is disposed close to the surface of the photosensitive member with a very small clearance. The photosensitive member has a conductive layer to which a bias voltage of the same polarity as the polarity of the toner charge can be applied. The transfer sheet is fed into the nib between the transfer roller and its abutting fixing roller, whereby the transfer and fixing of the toner image take place simultaneously.Type: GrantFiled: May 6, 1980Date of Patent: September 7, 1982Assignee: Ricoh Company, Ltd.Inventor: Yutaka Koizumi
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Patent number: 4338386Abstract: A toner image is formed on a photosensitive member by going through an electrophotographic process including charging, an original image exposure, and developing. The toner image on the photosensitive member is then transferred onto an image retention medium. Thus transferred toner image is temporarily fixed to the image retention medium by the application of heat, thereby enabling to make multiple copies by applying ink to the fixed toner image to form an ink image and bringing a copy paper in contact with the image retention medium for receiving the ink image. The toner image fixed to the image retention medium is completely removed after use thereby preparing the image retention medium for the subsequent use.Type: GrantFiled: September 18, 1980Date of Patent: July 6, 1982Assignee: Ricoh Company, Ltd.Inventor: Yutaka Koizumi
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Patent number: 4333063Abstract: An amplitude equalizer is provided for equalizing amplitude distorted signals within a predetermined frequency band. The amplitude equalizer comprises first means for splitting signals into first and second split signals. A first delay device receives one of the two split signals, and a second signal splitter splits the output of the first delay device into third and fourth split signals, the third split signal being applied to a second delay device having a delay equal to the delay of the first delay device. The output of the second delay device is combined with the second output from the first signal splitter in a first signal combiner, the output of which is applied to a circuit for adjusting the polarity and gain of the signal applied thereto. The output of the polarity and gain adjusting circuit is applied to a second signal combiner which combines the adjusted signal with the fourth output from the second signal splitter to thereby provide equalized signals.Type: GrantFiled: December 2, 1980Date of Patent: June 1, 1982Assignee: Nippon Electric Co., Ltd.Inventors: Toshihiko Ryu, Yutaka Koizumi