Liquid Transporting Apparatus and Method of Manufacturing Liquid Transporting Apparatus

A method of manufacturing a liquid transporting apparatus which includes a channel unit which has a plurality of pressure chambers arranged along a flat plane and in which the pressure chambers are separated by partition wall sections, and a piezoelectric actuator which is arranged on one surface of the channel unit, which changes selectively a volume of the plurality of pressure chambers and which includes a vibration plate which covers the plurality of pressure chambers, a piezoelectric layer which is arranged on a side of the vibration plate opposite to the pressure chambers to cover all of the plurality of pressure chambers as viewed from a direction orthogonal to the flat plane, a plurality of individual electrodes which are arranged on one surface of the piezoelectric layer corresponding to the plurality of pressure chambers respectively, and a common electrode which is arranged on the other surface of the piezoelectric layer, the method comprising the steps of:

• providing the channel unit;
• adhering the vibration plate to the partition wall sections of the channel unit;
• providing the piezoelectric layer to one surface of the vibration plate;
• and
• determining a thickness of the piezoelectric layer or a thickness of an adhesive layer between the vibration plate and the particle wall sections based on a parameter which is represented by A=((TV+Tp)3×(Ev+Ep)/2)Wc1/2 wherein a thickness of the vibration plate is Tv (mm), a coefficient of elasticity of the vibration plate is Ev (kg/mm2), the thickness of the piezoelectric layer is Tp (mm), a coefficient of elasticity of the piezoelectric layer is Vp (kg/mm2), and a length of each of the pressure chambers in a predetermined direction is Wc (mm).