Image forming apparatus

1. An image forming apparatus, comprising:

a main body device;

a detachable unit that is attached to the main body device to perform an image formation on a medium, and is detachable with respect to the main body device;

an operation part that allows the detachable unit to be detached from the main body device; and

a lock part that

locks the operation part in a first state at which the detachable unit is not at an image forming state to perform the image formation, and

releases the lock of the operation part in a second state at which the detachable unit is at the image forming state.

2. The image forming apparatus according to claim 1 , wherein

the lock part locks the operation part in the first state at which the detachable unit is detachable with respect to the main body device.

3. The image forming apparatus according to claim 2 , wherein

the lock part locks the operation part in the first state at which the detachable unit is not attached to the main body device.

4. The image forming apparatus according to claim 1 , further comprising:

an upper side opening and closing member that opens and closes an upper side with respect to the main body device, wherein

the lock part locks the operation part in the first state at which the upper side opening and closing member is in an open state with respect to the main body device.

5. The image forming apparatus according to claim 1 , further comprising:

a toner cartridge that contains toner to supply, and

a shutter member that blocks a supply of toner, wherein

the detachable unit is a development unit,

the toner cartridge is arranged to connect with the development unit when the development unit is attached to the main body device such that the toner in the toner cartridge is supplied to the development unit,

the shutter member blocks the supply of toner coming from the toner cartridge to the development unit, and

the operation part switches with the shutter member between a supply enabled state of the toner and a blocked state in which the supply of the toner is blocked.

6. The image forming apparatus according to claim 5 , further comprising:

a duct that has a supply port to supply the toner from the toner cartridge to the development unit, wherein

the shutter member reciprocates between an opening position and a closing position,

at the opening position, the shutter member opens the supply port to supply the toner at the supply enabled state, and

at the closing position, the shutter member closes the supply port to block the supply of the toner at the blocked state.

7. The image forming apparatus according to claim 6 , wherein

the development unit is further provided with a shutter through which the toner is supplied to the development unit from the toner cartridge,

the shutter is linked with the shutter member such that the shutter moves in correspondence with whether the shutter member is at the opening position or the closing position.

8. The image forming apparatus according to claim 5 , wherein

the lock part is a lock lever that locks the operation part by engaging with an engaging part provided in the operation part in the first state at which the development unit is not attached to the main body device, and releases the lock of the operation part by not engaging with the engaging part when the development unit is attached to the main body device.

9. The image forming apparatus according to claim 8 , further comprising:

one or more developer units that are identical to the development unit, each of the development units containing a toner of different color from others, wherein

one or more lock levers that are identical to the lock lever, wherein

the lock levers are each provided with the development units.

10. The image forming apparatus according to claim 8 , wherein

the operation part switches an engagement between the development unit and the toner cartridge.

11. The image forming apparatus according to claim 10 , further comprising:

a front side opening and closing member that opens and closes a front side with respect to the main body device, wherein

the operation part releases the engagement between the development unit and the toner cartridge by being pulled to a front side,

in the first state at which the operation part is pulled out to the front side and the development unit is not attached to the main body device, the lock lever engages with the engaging part provided with the operation part to lock the operation part so that the operation part does not move toward a rear side, and

when the operation part is locked so as not to move to the rear side, the front side opening and closing member comes into contact with the operation part before closing the front side of the main body device, and a movement thereof is restricted.

12. The image forming apparatus according to claim 1 , further comprising:

an upper side opening and closing member that opens and closes an upper side with respect to the main body device, wherein

the operation part switches an engagement between the detachable unit and the upper side opening and closing member.

13. The image forming apparatus according to claim 12 , wherein

in the first state at which the detachable unit and the upper side opening and closing member are engaged with each other and the upper side opening and closing member is opened with respect to the main body device, the lock part locks the operation part.

14. The image forming apparatus according to claim 13 , wherein

the operation part is provided in the upper side opening and closing member,

the upper side opening and closing member rotates about a shaft provided at a rear end side thereof, and

the locking part is a basket locking part that is formed at a front end side of a basket as the detachable unit in which the development unit is accommodated, and locks the operation part that is lifted from the main body device together with the upper side opening and closing member.