Developer conveyance device, image forming apparatus, and developer conveyance method

摘要

An image forming apparatus includes a developing device; a developer conveyance device including a developer container, a developer reservoir to receive developer discharged from the developer container, and a positive-displacement pump to discharge, from the developer reservoir, developer supplied to the developing device by alternately generating positive pressure and negative pressure due to volume changes; and a controller to control driving of the positive-displacement pump. When the controller recognizes a developer end state of the developer container, the controller lowers a developer conveyance capability of the positive-displacement pump from a setting used before the developer end state is recognized.

主权项

1. An image forming apparatus comprising:
a developing device; a developer conveyance device configured to convey developer to the developing device, the developer conveyance device including,
a developer container,a developer reservoir configured to receive developer discharged from the developer container,a positive-displacement pump configured to discharge, from the developer reservoir, developer supplied to the developing device by alternately generating positive pressure and negative pressure due to volume changes, anda developer amount detector configured to detect an amount of developer in the developer reservoir; and a controller configured to control driving of the positive-displacement pump, wherein,
when the controller recognizes a developer end state of the developer container, the controller is configured to lower a developer conveyance capability of the positive-displacement pump from a setting used before the developer end state is recognized,the controller is configured to control driving of the positive-displacement pump according to a signal from the developer amount detector,the controller is configured to drive the developer container for a set period when the signal from the developer amount detector indicates that the amount of developer in the developer reservoir is not greater than a set amount, andthe controller is configured to recognize the developer end state of the developer container when the amount of developer in the developer reservoir is not increased by driving the developer container for the set period.