Ink-jet head mounted with a driver IC, method for manufacturing thereof and ink-jet printer having the same

An ink-jet head comprising:

• (a) a head main body in which a plurality of nozzles, a plurality of pressure chambers which correspond to said plurality of nozzles, respectively, and a plurality of actuators which correspond to said plurality of nozzles, respectively, are provided,
• (b) a driver IC in which a drive circuit for outputting a drive signal to each of said plurality of actuators is provided,
• (c) connecting members for establishing connection between said drive circuit and each of said plurality of actuators so that said drive signal is transmittable therebetween,
• wherein said plurality of nozzles are arrayed on a first side of said head main body,
• wherein said driver IC is mounted on an opposite second side of said head main body,
• wherein said plurality of actuators are arranged on said second side of said head main body on which said driver IC is mounted,
• wherein each of said plurality of actuators includes an input terminal coupled to a corresponding one of said connecting members and a drive portion for producing drive force used to emit ink through a corresponding one of said plurality of nozzles upon receipt of said drive signal,
• wherein a drive portion group composed of an array of said drive portions of said plurality of actuators is provided on said second side of said head main body on which said driver IC is mounted,
• wherein said driver IC is mounted so as to lie astride said drive portion group;
• and
• wherein at least said driver IC, said connecting members, and said input terminals of said plurality of actuators are sealed by an encapsulating material which is applied such that a specified clearance is formed between said encapsulating material and said actuator drive portion group.

An ink-jet head comprising:

• (a) a head main body in which a plurality of nozzles, a plurality of pressure chambers which correspond to said plurality of nozzles, respectively, and a plurality of actuators which correspond to said plurality of nozzles, respectively, are provided,
• (b) a driver IC in which a drive circuit for outputting a drive signal to each of said plurality of actuators is provided,
• (c) connecting members for establishing connection between said drive circuit and each of said plurality of actuators so that said drive signal is transmittable therebetween,
• wherein each of said plurality of actuators includes an input terminal coupled to a corresponding one of said connecting members add a drive portion for producing drive force used to emit ink through a corresponding one of said plurality of nozzles upon receipt of said drive signal,
• wherein a drive portion group composed of an array of said drive portions of said plurality of actuators is provided on one side of said head main body,
• wherein said driver IC is positioned on the outside of said drive portion group of said head main body, lying astride said drive portion group with a specified clearance formed between itself and said drive portion group, and
• wherein at least said driver IC, said, connecting members, and said input terminals of said plurality of actuators are sealed by an encapsulating material which is applied such that a specified clearance is formed between said encapsulating material and said actuator drive portion group.

A method of manufacturing an ink-jet head which includes (a) a head main body in which a plurality of nozzles, a plurality of pressure chambers which correspond to said plurality of nozzles, respectively, and a plurality of actuators which correspond to said plurality of nozzles, respectively, are provided, and (b) a driver IC in which a drive circuit for outputting a drive signal to each of said plurality of actuators is provided,

• said ink-jet head manufacturing method including:
• (i) a step of temporarily affixing an adhesive to locations situated at both sides of a drive portion group composed of an array of a plurality of drive portions of said plurality of actuators in said head main body,
• (ii) a step of placing said driver IC onto said adhesives so that said driver IC lies astride said drive portion group,
• (iii) a step of wire bonding together, by means of bonding wires, output terminals of said drive circuit of said driver IC and corresponding input terminals of said plurality of actuators of said head main body.

An ink-jet head comprising:

• (a) a head main body in which a plurality of nozzles, a plurality of pressure chambers which correspond to said plurality of nozzles, respectively, and a plurality of actuators which correspond to said plurality of nozzles, respectively, are provided,
• (b) a driver IC in which a drive circuit for outputting a drive signal to each of said plurality of actuators is provided,
• (c) connecting members for establishing connection between said drive circuit and each of said plurality of actuators so that said drive signal is transmittable therebetween,
• wherein said plurality of nozzles are arrayed on a first side of said head main body,
• wherein said driver IC is mounted on an opposite second side of said head main body,
• wherein said plurality of actuators are arranged on said second side of said head main body on which said driver IC is mounted,
• wherein each of said plurality of actuators includes an input terminal coupled to a corresponding one of said connecting members and a drive portion for producing drive force used to emit ink through a corresponding one of said plurality of nozzles upon receipt of said drive signal,
• wherein a drive portion group composed of an array of said drive portions of said plurality of actuators is provided on said second side of said head main body on which said driver IC is mounted,
• wherein said driver IC is mounted so as to lie astride said drive portion group, wherein said driver IC is, at both ends thereof, fixedly supported on said head main body,
• wherein said connecting members are bonding wires for establishing connection between said input terminals of said plurality of actuators and corresponding output terminals of said drive circuit,
• wherein the both ends of said driver IC are supported on said head main body through spacers, and each of said spacer height Ts is set such that
• Ts>(W·Ld3)/(4·E·Wd·Td3),
• Where W indicates a force that is applied to the driver IC at the time of wire bonding, Ld indicates a length of the driver, E indicates the longitudinal elastic coefficient of the driver IC, Wd indicates a width of the driver, and Td indicates a height of the driver IC.

An ink-jet head comprising:

• (a) a head main body in which a plurality of nozzles, a plurality of pressure chambers which correspond to said plurality of nozzles, respectively, and a plurality of actuators which correspond to said plurality of nozzles, respectively, are provided,
• (b) a driver IC in which a drive circuit for outputting a drive signal to each of said plurality of actuators is provided,
• (c) connecting members for establishing connection between said drive circuit and each of said plurality of actuators so that said drive signal is transmittable therebetween,
• wherein each of said plurality of actuators includes an input terminal coupled to a corresponding one of said connecting members and a drive portion for producing drive force used to emit ink through a corresponding one of said plurality of nozzles upon receipt of said drive signal,
• wherein a drive portion group composed of an array of said drive portions of said plurality of actuators is provided on one side of said head main body,
• wherein said driver IC is positioned on the outside of said drive portion group of said head main body, lying astride said drive portion group with a specified clearance formed between itself and said drive portion, group,
• wherein said driver IC is, at both ends thereof, fixedly supported on said head main body,
• wherein said connecting members are bonding wires for establishing connection between said input terminals of said plurality of actuators and corresponding output terminals of said drive circuit,
• wherein the both ends of said driver IC are supported on said head main body through spacers, and
• each of said spacer height Ts is set such that
• Ts>(W·Ld3)/(4·E·Wd·Td3),
• Where W indicates a force that is applied to the driver IC at the time of wire bonding, Ld indicates a length of the driver, E indicates the longitudinal elastic coefficient of the driver IC, Wd indicates a width of the driver, and Td indicates a height of the driver IC.