Liquid drop ejecting head, image forming device, and method of manufacturing liquid drop ejecting head

A liquid drop ejecting head comprising:

• a nozzle plate that forms nozzles to eject liquid drops;
• a channel member that forms pressurizing liquid chambers which communicate with the nozzles, respectively;
• and
• a diaphragm that forms a bottom surface of each of the pressurizing liquid chambers, the diaphragm, the channel member and the nozzle plate being laminated on top of each other, wherein:
• interface surfaces of the channel member and the diaphragm are bonded by an adhesive;
• the diaphragm is formed to have a laminated structure in which the number of lamination layers is varied at different locations of the diaphragm;
• the diaphragm includes an opening and a filter part, the filter part having plural filtering holes formed in the opening for supplying a liquid to the pressurizing liquid chambers;
• and
• a side wall of the channel member is disposed to contact or located in a vicinity of the filter part, and the side wall and a thick-walled portion containing the largest number of lamination layers in the diaphragm do not overlap with each other in a laminating direction, and
• wherein the diaphragm has a laminated structure containing three layers joined on top of each other and the thick-walled portion contains a first layer in which the filter part is formed, a second layer laminated on the first layer, and a third layer laminated on the second layer, and
• wherein the first layer and the second layer of the thick-walled portion overlap with the side wall of the channel member in the laminating direction, and the third layer does not overlap with the side wall in the laminating direction.

A liquid drop ejecting head comprising:

• a nozzle plate that forms nozzles to eject liquid drops;
• a channel member that forms pressurizing liquid chambers which communicate with the nozzles, respectively;
• and
• a diaphragm that forms a bottom surface of each of the pressurizing liquid chambers, the diaphragm, the channel member and the nozzle plate being laminated on top of each other, wherein:
• interface surfaces of the channel member and the diaphragm are bonded by an adhesive;
• the diaphragm is formed to have a laminated structure in which the number of lamination layers is varied at different locations of the diaphragm;
• the diaphragm includes an opening and a filter part, the filter part having plural filtering holes formed in the opening for supplying a liquid to the pressurizing liquid chambers;
• and
• a side wall of the channel member is disposed to contact or located in a vicinity of the filter part, and the side wall and a thick-walled portion containing the largest number of lamination layers in the diaphragm do not overlap with each other in a laminating direction, and
• wherein the diaphragm has a laminated structure containing three layers joined on top of each other and thick-walled portion contains a first layer in which the filter part is formed, a second layer laminated on the first layer, and a third layer laminated on the second layer, and
• wherein the first layer and the third layer of the thick-walled portion overlap with the side wall of the channel member in the laminating direction, and the second layer does not overlap with the side wall in the laminating direction.

A method of manufacturing a liquid drop ejecting head, the liquid drop ejecting head including a diaphragm, a channel member and a nozzle plate which are laminated on top of each other, the method comprising:

• forming the diaphragm to have a laminated structure in which the number of lamination layers is varied at different locations;
• forming a filter part having plural filtering holes in an opening of the diaphragm for supplying a liquid to pressurizing liquid chambers of the channel member;
• applying an adhesive to interface surfaces of the channel member and the diaphragm;
• arranging a thick-walled portion containing the largest number of lamination layers in the diaphragm and a side wall of the channel member disposed to contact or located in a vicinity of the filter part, so that the thick-walled portion and the side wall do not overlap each other in a laminating direction;
• and
• pressurizing the side wall and the thick-walled portion to bond the channel member and the diaphragm together by the adhesive,
• wherein a distance between the thick-walled portion and the filter part is greater than a distance between the side wall of the channel member and the filter part in a direction perpendicular to a nozzle arraying direction in which the nozzles are arrayed.