Patent ID: 7407267

Claim:
A liquid droplet ejection head, comprising: a base plate which has a common supply flow channel formed throughout an entire dimension in a lengthwise direction of the base plate; a plurality of short head modules which are assembled on the base plate to form a long head, each of the plurality of short head modules including ejection ports ejecting droplets of liquid and a liquid flow channel supplying the liquid to the ejection ports from the common supply flow channel; a positioning mechanism through which the short head modules are detachably installed on the base plate; and a check valve provided on the base plate at a connecting section between the common supply flow channel of the base plate and the liquid flow channel in each of the plurality of short head modules, wherein when replacing one of the plurality of short head modules, the one of the plurality of short head modules is removed after the liquid is emptied out of the one of the plurality of short head modules through the check valve.