An image forming system includes an image forming apparatus including an AC-DC converter and a main board, and a sub board having a sub connector connectable with a main connector of the main board. When the sub board is not connected with the main board, a main DC-DC converter on the main board converts a DC voltage from the AC-DC converter into a first DC voltage and output the first DC voltage to a circuit element for image formation. When the sub board is connected with the main board, the AC-DC converter outputs the DC voltage to a sub DC-DC converter on the sub board via the main connector and the sub connector, and the sub DC-DC converter converts the DC voltage from the AC-DC converter into a second DC voltage and output the second DC voltage to the circuit element via the sub connector and the main connector.

The present disclosure provides a process cartridge and an image-forming apparatus. The process cartridge, detachably mounted on an image-forming apparatus, includes a cartridge body; a photosensitive drum, rotatably disposed on the cartridge body; and a chip, configured to be disposed on the cartridge body, where the chip includes a power supply contact configured to receive power provided by the image-forming apparatus. The power supply contact is configured to be electrically connected to a discharge component, and the discharge component is configured to eliminate residual charge on the photosensitive drum.

A metal frame provides a ground potential. An image forming unit forms a toner image on a sheet. A fixing apparatus fixes the toner image on the sheet. The fixing apparatus comprises a heating element for generating heat by being supplied with power from an alternating current power source. An insulating layer covers the heating element. A conductive layer contacts the insulating layer and insulated from the metal frame. A tube-shaped member is heated by the heating element. A pressing member is arranged opposing the tube-shaped member and forms a nip portion in cooperation with the tube-shaped member. A capacitive element whose one end is connected to the metal frame and whose other end is connected to the conductive layer of the fixing apparatus.

An image forming apparatus includes an image forming unit configured to form an image on a recording material, a printed circuit board including a voltage generation unit mounted thereon and configured to generate a voltage to be applied to the image forming unit, a conductive member provided on the printed circuit board, to which the voltage generated by the voltage generation unit is applied, an elastic member including an arm portion configured to be biased toward the conductive member, and configured to connect the conductive member and the image forming unit, and a holding unit configured to hold the arm portion of the elastic member at a position where the arm portion is not in contact with the conductive member.

A board support member is a metal plate member to which a printed circuit board is attached. A spacer is arranged between the printed circuit board and the board support member. The board support member has a clamp hole that is a through hole, and has a spacer engagement portion that is an annular protrusion formed by burring. The spacer has a first end formed with a clamp having a flexible portion capable of being inserted through the clamp hole and engaging with the spacer engagement portion. The spacer further has a second end opposite the first end and facing the surface of the printed circuit board.

Provided is an image forming apparatus that is unlikely to fail due to heat from a power supply unit. The image forming apparatus includes a housing having a space for internal sheet discharging, and a power supply unit provided in the housing and adjacent to the space.

An image forming apparatus includes an attachment section to which a first fixing unit that performs a fixing operation of fixing an image on a recording material by using power from an alternating current power supply and a second fixing unit that performs the fixing operation by using power from a direct current power supply are attached, an alternating current power supply section that receives the power supplied from the alternating current power supply, and a direct current power supply section that receives the power supplied from the direct current power supply, in which the attachment of the first fixing unit to the attachment section and the supply of the power from the direct current power supply to the direct current power supply section are not executable simultaneously, and the attachment of the second fixing unit to the attachment section and the supply of the power from the alternating current power supply to the alternating current power supply section are not executable simultaneously.

A heating device includes a heater, a switching element connected between the heater and an AC power, and a controller performing a wave number control. A power control pattern includes a first pattern of which a control period is a first number, equal to or more than 2, of half waves and which satisfies a positive/negative symmetry, and a second pattern of which the control period is a second number, equal to or more than 2 and divisible by 4, of half waves and which satisfies the positive/negative symmetry. The controller sets the second pattern in a case where a supplying power duty is a first duty and sets the first pattern in a case where the supplying power duty is a second duty which is the supplying power duty larger or smaller by one step than the first duty, and performs wave number control.