Matsushita Electric Industrial Co., Ltd.

Panasonic Corporation

Other

Matsushita Electric Industrial Co., Ltd. - Wireless Research Laboratory

Noboru Katakabe

Kenji Asakura

Masanori Yoshikawa

Masaru Imai

Keisuke Fujimoto

Masahiro Aizawa

Keizou Takeuchi

Shigemitsu Tani

Atsushi Sogami

Akihiro Yasuda

Noriyuki Tajima

Toshiharu Sasaki

Shuichi Watanabe

Masahiro Samei

Hajime Yamamoto

Hiroshi Terada

Kouji Ikeda

Tomoyuki Noguchi

Isao Yamaguchi

Yasutaka Tamai

Masaru Onishi

Orio Yoshii

Hiroyuki Suzuki

Masaichiro Tatekawa

Hideki Tatematsu

Hideaki Yamada

Youichi Nakamura

Teruyuki Naka

Yuichi Hatase

Akira Kumon

Soichiro Mima

Yoshio Horiike

Katsutoshi Ogawa

Yuji Nakamura

Shunji Onobori

Masaaki Nakano

Junichi Nawama

Hitoshi Hisada

Takehisa Takamiya

Yoshihiro Yokoyama

Hiromichi Miyoshi

Yasutaka Nakajima

Tetsuhiro Sano

Masaomi Inoue

Naoto Matsuo

Hiroshi Yasumoto

Syuuiti Watanabe

Manabu Kitajima

Yoshikawa Masanori

Kouzou Ezawa

Shouji Nishitani

Hiroaki Takase

Masawo Otsuka

Masahiro Alzawa

A heating apparatus which can increase the temperature of a heating element to a target temperature in a short time and ensures temperature uniformity of the heating element. In the heating apparatus, when the specific resistance of a material of a heat generating layer of a heating roller is &#x3c1; (&#x3bc;'&#x3a9;cm), the average thickness of the heat generating layer is 5&#x3c1; (&#x3bc;m) or more but not more than 15&#x3c1; (&#x3bc;m), and the thickness error is 1.2&#x3c1; (&#x3bc;m) or less. For instance, when the heat generating layer is copper having a specific resistance of 1.7 (&#x3bc;&#x2032;&#x3a9;cm), the average thickness of the heat generating layer is 8-25 (&#x3bc;m), and the thickness error is 2 (&#x3bc;m) or less. Thus, the heating roller having a short heat increasing time and excellent temperature uniformity is provided.

Heating apparatus including electrically conductive heat producing layer providing short heat increase time and temperature uniformity

A fixing device for reducing, without fail, the heating output without using a control circuit if an excessive temperature rise of a rotary heating member is predicted, even if the control circuit fails or runs away. In the fixing device, heating of a fixing belt for heat-fixing an unfixed image on a recording medium is controlled by a body-side processor. When the fixing belt stops or rotates at a rotational speed equal to or below a threshold, an oscillation stop circuit stops the oscillation of an inverter circuit to stop the heating, independently of the processor. To check the operation of a rotation detection circuit for detecting the rotating state of the fixing belt (fixing roller) and the oscillation stop circuit, self-diagnosis is utilized to ascertain that the fixing belt is not heated by giving a heating instruction when the condition of not heating the fixing belt is satisfied is performed when the power is turned on or is performed regularly during standby.

Fixing apparatus and image forming apparatus including power suppression

A fixing unit is provided with a fixing belt that heats recording paper that bears and moves a toner image, an exciting coil that generates magnetic flux in the fixing belt and causes the fixing belt to produce heat by electromagnetic induction, and a heat production adjustment section that adjusts the calorific value distribution of the fixing belt by adjusting the magnetic flux acting upon the fixing belt.

Image heating apparatus and image forming apparatus including synchronization of magnetic flux generation

A heat generating roller, fixing equipment and an image forming apparatus in which warm-up time is shortened while preventing excessive temperature rise and good fixing performance is realized by preventing offset. The heat generating roller is formed principally by laying a high permeability conductive layer and a nonmagnetic conductive layer in layer. When a voltage is applied from a power supply to an exciting coil and an alternating current flow, magnetic flux is generated around the exciting coil and a magnetic field is formed. Magnetic coupling of a system including the heat generating roller and the exciting coil is advantageous at a low temperature and heat generation of the heat generating roller is accelerated. When the Curie point is exceeded, skin depth increases and skin resistance decreases, which suppresses generation of Joules heat and reduces heat generation of the heat generating roller.

Heat generating roller, fixing equipment, and image forming apparatus

A shield plate that has a plate portion stretching in a width direction of exciting coils is positioned so that end portions of the shield plate oppose the exciting coils. The present invention prevents elongated warm-up time and reduces a dramatic temperature drop when printing on thick paper in a low temperature environment.

Fixing apparatus and image forming apparatus

In a fixing apparatus using an induction heating type of heating apparatus, there are provided an excitation apparatus that generates magnetic flux, an opposed core located opposite the excitation apparatus, a fixing belt that is induction-heated by the aforementioned magnetic flux, and magnetism masking elements that block magnetic paths corresponding to paper non-passage areas of fixing belt between the excitation apparatus and the opposed core. By blocking magnetic paths between the excitation apparatus and the opposed core by the magnetism masking elements, magnetic flux that induction-heats the fixing belt is effectively masked, and an excessive rise in temperature of paper non-passage areas of fixing belt is prevented.

Fixing device

An image heating apparatus is provided that enables the entire width of a heat-producing medium to be heated uniformly and an excessive rise in temperature to be prevented, without making the configuration complex. In a fixing unitin which this apparatus is applied, a fixing beltis an annular member that has an inner peripheral surface and an outer peripheral surface, and produces heat through the action of magnetic flux. An exciting coilis located in proximity to the outer peripheral surface of fixing beltand generates magnetic flux that acts upon fixing beltA suppression memberis located in proximity to inner peripheral surface of fixing beltand reduces, of the magnetic flux generated by exciting coilmagnetic flux that acts upon a paper non-passage area of fixing belt

Image heating device and image forming device

A fixing apparatus that enables the calorific value of a heat-producing rotating element to be stabilized and the heat production efficiency of that heat-producing rotating element to be improved. A fixing apparatus () is equipped with a heat-producing sleeve (), an induction heating apparatus (), a magnetic field absorption member () that absorbs a magnetic field generated by the induction heating apparatus (), and a fixing roller () and pressure roller () that grip and rotate the heat-producing sleeve (). The magnetic field absorption member () is located in an area opposite an exciting coil () with the heat-producing sleeve () between, and absorbs a magnetic field generated by the induction heating apparatus (). The heat-producing sleeve () is composed of a nonmagnetic metallic material of thickness in the range from 10 &#x3bc;m to 500 &#x3bc;m and specific resistance of 80&#xd7;10&#x3a9;cm or less.

Fixing apparatus

An electromagnetic induced heating roller comprises a core member, an elastic layer, induction heating layer, and a mold release layer in this order from inside to outside. Further, a magnetic shield layer for preventing a magnetic flux from penetrating into the core member is interposed between the induction heating layer and the core member. The production of an alternating magnetic field from a magnetic field generating device, a leakage flux having penetrated through the induction heating layer is trapped by the magnetic shield layer. As a result, most of the impressed alternating magnetic flux is consumed for heating the heating layer, resulting in an improvement in the heating efficiency. A trouble is prevented which is generated by heating the bearing of the core member.

Electromagnetic induction heat generating roller, heating device, and image forming apparatus

A heating roller () includes a heat generating layer () that generates heat by electromagnetic induction, a heat insulating layer (), and a supporting layer (), which are provided inwardly in this order. The supporting layer () is formed of a material having a specific resistance of 1&#xd7;10&#x3a9;m or higher. Therefore, even when the heat generating layer () has a thickness smaller than a skin depth, i.e. a thickness defined by a flow of an induction current, so that magnetic flux penetrates the heat generating layer () and even reaches the supporting layer (), heat generation of the supporting layer () under an eddy current can be suppressed. Thus, the heat generating layer () can be decreased in thermal capacity, and heat generation of the supporting layer () is suppressed, so that only the heat generating layer () can be heated efficiently. As a result, a warm-up time can be reduced. Further, breakage by heat of, for example, bearings supporting the heating roller () can be prevented.

Heating roller, image heating apparatus, and image forming apparatus

An image heating device according to an embodiment of the present invention includes a heat generator that has an outer surface and that generates heat by induction heating and a heater positioned close to the outer surface of the heat generator, the heater being configured to heat the heat generator by induction heating. A positioner is located close to an end of the heater, the positioner being configured to position the heater with respect to the heat generator. A vibration absorber is attached to the positioner and is configured, in one embodiment, to viscoelasticly absorb vibration of the heater produced by a vibration caused by an electromagnetic repulsive force acting between the heat generator and the heater when the heater heats the heat generator by induction heating.

Image heating device

An image heating device includes a heat generating member that heats a body to be heated that is allowed to travel while carrying an image, an excitation unit that is provided close to the heat generating member and generates magnetic flux so as to cause the heat generating member to generate heat by electromagnetic induction, and a heat generation suppressing unit that suppresses an amount of heat generated in the heat generating member by regulating magnetic flux generated by the excitation unit. The heat generation suppressing unit suppresses heat generation of the heat generating member in a region corresponding to a region including at least a center portion of the body to be heated in a width direction. Thus, an amount of heat generated in the width direction can be regulated using a simple configuration at a reduced cost. Further, when the heat generation suppressing unit is operated, diffusion of magnetic flux into a wide area can be prevented.

Image heating device using induction heating and image forming apparatus

An image forming apparatus uses a plurality of image forming units having photosensitive drums and that are arranged rotatable in a vertical plane such that the image forming units are shifted sequentially to an image forming position. Each of the image forming units has a rectangular concave portion along its longitudinal direction which contains a handle made of an elastic rectangular-shaped plate. The handle has elongated holes extending in the longitudinal direction at both ends of the handle which engage anchoring members provided at the concave portion. The handle is allowed to be contained within the concave portion by its elastic force and is allowed to be pulled out from the concave portion by a user's finger inserted into an entrance groove provided only at a side opposite to the photosensitive drum with respect to the handle. In addition, the image forming apparatus has a door for allowing the attaching/detaching of the image forming units wherein the door has a protrusion which is capable of contacting the handle.

Image forming apparatus having a plurality of image forming units with handles

An image forming apparatus includes a plurality of image forming units having a developer, a charger, and a photosensitive member; a carriage for retaining the plurality of image forming units so that they can be removed and installed, and which rotates the plurality of image forming units between an image forming position and other positions; a laser exposing device for exposing the photosensitive member at an image forming position; an intermediate transfer belt for accepting a toner image formed on the photosensitive member at the image forming position, and forming a color image; an output shaft for coupling with at least one axis end portion of the photosensitive member in the image forming position in the axial direction of the photosensitive member, and positioning the photosensitive member at a proper position; a rotation stop portion for positioning the rotation orientation of the image forming units with respect to the axis of the photosensitive members; and a retransfer roller for transferring the color image formed on the intermediate transfer belt at a retransfer position onto recording paper. Thus, it is possible to retain the image forming unit precisely and reliably at a proper position.

Image forming apparatus with plural color image forming units moveable into image forming position

An image forming apparatus capable of removing a toner remaining on the transfer belt (toner supporting member) with a simple configuration. The image forming apparatus includes an intermediate transfer belt that moves with charged toner supported on the surface thereof; a cleaner roller that is rotated while being pressed onto the intermediate transfer belt; a power source for supplying potential for electrically attracting the toner to the cleaner roller from the intermediate transfer belt; and a pretreatment roller that is pressed onto the intermediate transfer belt upstream from the cleaner roller in the moving direction of the intermediate transfer belt.

Image forming apparatus, transfer belt unit, cleaning device and cleaner unit used for image forming apparatus

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Uji, Japan

Noboru Katakabe