Ultrasonic vibration welding apparatus

1. An ultrasonic vibration welding apparatus, comprising:

a table on which a welding target is placed;

an ultrasonic welding head unit that executes an ultrasonic vibration operation of applying ultrasonic vibrations from an ultrasonic welding portion;

a pressurizing mechanism that is coupled to said ultrasonic welding head unit and executes a pressurizing operation of pressurizing said ultrasonic welding head unit toward a side of said table;

a lowering mechanism that executes a lowering operation of lowering said ultrasonic welding head unit and said pressurizing mechanism at once; and

a control unit configured to execute a control operation of controlling said ultrasonic vibration operation by said ultrasonic welding head unit, said pressurizing operation by said pressurizing mechanism, and said lowering operation by said lowering mechanism, wherein

said ultrasonic welding head unit includes a plurality of ultrasonic welding head units,

said pressurizing mechanism includes a plurality of pressurizing mechanisms provided corresponding to said plurality of ultrasonic welding head units, said plurality of pressurizing mechanisms each executes said pressurizing operation on the corresponding ultrasonic welding head unit among said plurality of ultrasonic welding head units,

said lowering operation executed by said lowering mechanism includes a batch multiple lowering operation of lowering said plurality of ultrasonic welding head units and said plurality of pressurizing mechanisms at once,

said control unit configured to causes each of said plurality of ultrasonic welding head units to execute said ultrasonic vibration operation with, as a trigger, recognition of an entire welding portion contact state,

said entire welding portion contact state is a state where said plurality of ultrasonic welding head units all contact application portions of said welding target by said lowering operation of said lowering mechanism,

by said configured control unit,

said lowering mechanism executes said lowering operation with a lowering pressing force,

each of said plurality of pressing mechanisms executes said pressurizing operation with a pressurizing pressing force,

said lowering pressing force is set to be larger than said pressurizing pressing force,

said lowering mechanism continuously executes said lowering operation during executing said ultrasonic vibration operation by each of said plurality of ultrasonic welding head units, and

each of said lowering pressing force and said pressurizing pressing force is set to a constant pressure value in advance, and said lowering pressing force and said pressurizing pressing force are maintained during executing said ultrasonic vibration operation by each of said plurality of ultrasonic wielding head units.

2. The ultrasonic vibration welding apparatus according to claim 1 , wherein

said pressurizing mechanism includes an air cylinder, and said air cylinder is coupled to said ultrasonic welding head unit via a piston rod, and

said pressurizing pressing force is applied from the piston rod of said air cylinder to said ultrasonic welding head unit.

3. The ultrasonic vibration welding apparatus according to claim 2 , wherein

said control operation performed by said control unit includes the steps of:

(a) arranging said ultrasonic welding portion of each of said plurality of ultrasonic welding head units to be located above an application portions of said welding target;

(b) causing each of said plurality of pressurizing mechanisms to execute said pressurizing operation;

(c) causing said lowering mechanism to execute said lowering operation; and

(d) causing each of said plurality of ultrasonic welding head units to execute said ultrasonic vibration operation with, as a trigger, recognition of said entire welding portion contact state.

4. The ultrasonic vibration welding apparatus according to claim 3 , wherein

said air cylinder further has a position detection unit that detects a position of a piston inside the air cylinder.

5. The ultrasonic vibration welding apparatus according to claim 1 , wherein said welding target includes:

a glass substrate; and

an electrode disposed on said glass substrate.