摘要:
A belt-type fixing device for an image forming apparatus is capable of raising a temperature to a level suitable for a fixing process in a short period of time with high heating efficiency. A fixing belt is entrained in spanning relation between a heating plate providing a heat generator on the inner surface of the semi-cylindrical plate and a pressing pad disposed at a distance from the heating plate. A pressing roller is disposed at a position opposing the pressing pad. The fixing belt is revolved by rotating the pressing roller. A recording medium having a toner adhered thereto is caused to pass through a nip portion of the fixing belt and the pressing roller.
摘要:
A heating device comprises an endless rotary member, a resistance heating member, a current receiver member provided at the endless rotary member and a current supply member being in contact with the current receiver member.In a form, the current supply member is made of a sintered material containing copper and carbon, and a content of the copper in the sintered material is in a range from 55% to 80% by weight.In another form, a contact surface of the current receiver member is formed of a material harder than the current supply member. The contact surface of the current receiver member and the contact surface of the current supply member have surface roughnesses satisfying a relationship of (surface roughness of the current receiver member).ltoreq.(surface roughness of the current supply member). The surface roughness Ra of the current receiver member is in a range from 0.3 .mu.m to 5.5 .mu.m. The surface roughness Ra of the current supply member is equal to or smaller than 5.5 .mu.m.
摘要:
This invention is related to a power supply unit used in an image forming apparatus having a induction heat fusing device. In the power supply unit, each of a first and a second rectifying circuits rectifies AC voltage from a power supply to generate DC voltage. An inverter circuit generates a high frequency voltage to be applied to a coil of the induction heat fusing device by switching the DC voltage from the first rectifying circuit. A switching circuit switches the DC voltage from said second rectifying circuit and generates AC voltage. A transformer receives the AC voltage from the switching circuit and outputs a transformed voltage to be apply to a component of the image forming apparatus. The inverter, second rectifying circuit and switching circuit are connected to a common ground line.
摘要:
The present invention is related to a fixing device for fusing and fixing an unfixed toner image on a recording sheet. In the fixing device, a heating member such as rollers and endless belts and the like, is heated to a fixing temperature. An endless belt is provided opposite the heating member and is pressed against the heating member by a pressure member provided inside the endless belt. The heating member is driven in rotation in a transport direction of the recording sheet and the endless belt is driven in conjunction with the rotation of the heating member. The recording sheet bearing a toner image passes between the heating member and the endless belt while in this state, and the toner image is heated by the heating member so as to be fused onto the recording sheet under the pressure produced between the heating member and endless belt while the recording sheet is transported therebetween.
摘要:
An induction heating fixing apparatus is disclosed which in characterized by comprising an object to be heated formed of an electroconductive material, a coil for effecting induction heating on the object to be heated, an inverter circuit for effecting the flow of a high frequency to the coil, a thermistor for detecting the temperature of the object to be heated, a control circuit electrically insulated from the inverter circuit and adapted to control the inverter circuit based on the temperature detected by the thermistor so as to keep the object to be heated at a temperature in a prescribed range, and an insulating switch for transmitting the control signal from the control circuit in an electrically insulated state to the inverter circuit.
摘要:
The induction-heating apparatus of this invention contains a conductive member, a power source, and a first and a second induction coil connected to the power source and adapted for causing the conductive member to generate an induced current, the first and the second induction coil being parallelly connected. The induction coil is formed by winding a copper wire round a core in such a manner that the numbers of turns of the copper wire gradually decrease from the lowermost layer approximating most closely to the core to the upper layers. This heating apparatus has the thickness of the induction coil in the range of 0.2-0.8 mm. The gap between the induction coil and the conductive member is in the range of 0.5-4.0 mm. This heating apparatus has the induction coil thrust out of the conductive member. The induction coil is formed of a Litz wire.
摘要:
In the printing apparatus wherein the laser diode is used as light source for writing images on an image carrier, a control transistor is serially connected to the laser diode. The magnitude of the drive current for driving the laser diode is adjusted in accordance with the magnitude of the base current of the control transistor. The base current of the control transistor is turned on when the main power supply is implemented. That is, the control transistor is pre-heated up to print command. Consequently, the drive current is stable from the initial image formation after the main power supply is turned on.
摘要:
An induction heating fixing device comprises a heat roller in which coil assemblies are disposed. The coil assemblies are aligned axially of the roller to produce magnetic flux in a direction orthogonal to the axis of the heat roller.
摘要:
In a receiver-integrated condenser, a super-cooling portion for cooling liquid refrigerant from a receiving unit is disposed between first and second condensing portions in a core portion in a vertical direction. Therefore, in an engine-idling, even when high-temperature air having passed through the receiver-integrated condenser is introduced again toward an upstream air side of the receiver-integrated condenser through a lower side of the receiver-integrated condenser, the high-temperature air is not introduced toward the arrangement position of said super-cooling portion, because the super-cooling portion is positioned at an upper side from the second condensing portion. Thus, super-cooling performance of refrigerant in the super-cooling portion of the core portion is prevented from being decreased even in the engine idling.
摘要:
A fixing belt is applied to a fixing apparatus of an electronic photography type printer. The fixing belt consists of a belt base and an elastic layer having a thickness of 200 .mu.m or more formed on the belt base. The elastic layer consists of first, second and third elastic layers arranged in that order from the base side, and is deformable to conform to the surface shape of a recording paper so that all unfixed toner held on the recording paper can be pressed. The second elastic layer is a barrier layer for preventing releasing agent from permeating and the belt from swelling to suppress the thickening of the elastic layer as a whole and maintain the belt thickness within a range that does not cause any image noises.