Image forming apparatus

An image forming apparatus comprising:

• an image forming portion that performs image formation on a recording medium using toner;
• a toner storage container that stores the tonner used in the image forming portion;
• a mounting portion in which the toner storage container is removably mounted;
• a detection mechanism that detects the toner storage containers mounted in the mounting portion;
• and
• a control portion that enables the image forming portion to perform image forming operation when the detection mechanism detects the toner storage container, wherein
• the toner storage container has a coupling portion in a downstream end part thereof in an insertion direction into the mounting portion,
• the mounting portion has a coupled portion that couples to the coupling portion when the toner storage container is inserted up to a predetermined mounting position,
• the detection mechanism has:
• a detection circuit including:
• a first contact spring provided in the coupled portion;
• a second contact spring having a plurality of contact terminals that contact the first contact spring;
• a ground line to one end of which the first contact spring is connected and of which another end is grounded;
• a signal line to which the second contact spring is connected;
• a power supply connected to the signal line, and
• a detection board having a detection portion that detects a voltage applied from the power supply to the signal line as a detection signal;
• and
• a plurality of electrically insulating key members provided in the coupling portion and protruding toward the coupled portion,
• with the toner storage container removed from the mounting position, the first contact spring and the contact terminals are in a contacting state,
• when the toner storage container is inserted up to the mounting position, the key member moves to between the first contact spring and the contact terminals such that the first contact spring and the contact terminals turn from the contacting state to a non-contacting state, and
• when the first contact spring and the contact terminals turn from the contacting state to the non-contacting state, the control portion detects the toner storage container mounted in the mounting portion based on a change in the detection signal detected by the detecting portion.