ULTRASONIC WELDING APPARATUS
An ultrasonic welding apparatus and method for detaching or effecting release of an ultrasonic welding tool stuck or attached to a weldment. The method includes the step of utilizing a mechanism mounted adjacent to the ultrasonic welding tool to hold the weldment in position during welding and/or while the ultrasonic welding tool is withdrawn and, if necessary, using the mechanism to detach the weldment from the ultrasonic welding tool. The method contemplates providing a twist, rotary or axial motion to one of the ultrasonic welding tool or weldment to effect release of the ultrasonic welding tool. The apparatus may include a clamp member having a distinct clamping area or pad located adjacent to the sonotrode or anvil of the ultrasonic welding tool. The clamp mechanism provides vibration control, noise mitigation, and a more uniform boundary condition during welding and facilitates part release upon the completion of the welding process.
1 . An ultrasonic welding apparatus comprising:
a frame;
an ultrasonic welding device attached to said frame, said ultrasonic welding device including a sonotrode;
a drive mechanism attached to said frame and said sonotrode for moving said sonotrode into engagement with a workpiece to perform an ultrasonic welding operation;
a clamp member, said clamp member mounted to said frame for movement independent of said sonotrode, said clamp member operative to engage said workpiece; and
clamp member having a clamp surface for contacting said workpiece, said clamp surface extending only partially about said sonotrode.
2 . An ultrasonic welding apparatus as set forth in claim 1 wherein said clamp surface includes a pair of polygonal shaped surfaces extending on opposite sides of said sonotrode.
3 . An ultrasonic welding apparatus as set forth in claim 1 wherein said clamp surface is formed of a material different from that of said clamp body.
4 . An ultrasonic welding apparatus as set forth in claim 1 wherein said clamp surface includes opposed clamp pads spaced from said sonotrode to isolate the workpiece during the ultrasonic welding process.
5 . An ultrasonic welding apparatus as set forth in claim 1 wherein said clamp member includes a cooling assembly.
6 . An ultrasonic welding apparatus as set forth in claim 1 wherein said sonotrode includes a contact surface, said contact surface having a centerline, said centerline offset from a centerline of said sonotrode.
7 . An ultrasonic welding apparatus as set forth in claim 5 wherein said clamp surface is positioned offset from said centerline of said sonotrode.
8 . An ultrasonic welding apparatus comprising:
a frame;
an ultrasonic welding device attached to said frame, said ultrasonic welding device including a sonotrode;
a drive mechanism attached to said frame and said sonotrode for moving said sonotrode into engagement with a workpiece to perform an ultrasonic welding operation;
a clamp member, said clamp member mounted to said frame for movement independent of said sonotrode, said clamp member including a clamp pad operative to engage the workpiece.
9 . An ultrasonic welding apparatus as set forth in claim 8 wherein said clamp pad and said clamp member are formed of different materials.
10 . An ultrasonic welding apparatus as set forth in claim 8 wherein said clamp pad is formed of a plastic material.
11 . An ultrasonic welding apparatus as set forth in claim 8 wherein said clamp pad is formed of a metal material.
12 . An ultrasonic welding apparatus as set forth in claim 8 wherein said clamp member is operative on one side of the weldment only.
13 . An ultrasonic welding apparatus as set forth in claim 8 wherein actuation of the upper and lower clamp members is independent of one another.
14 . An ultrasonic welding apparatus as set forth in claim 8 including a plurality of spaced apart clamp pads operative to engage the workpiece
15 . An ultrasonic welding apparatus as set forth in claim 14 wherein said clamp pads are linearly offset from one another on opposing sides of said sonotrode.
16 . An ultrasonic welding apparatus as set forth in claim 14 wherein said clamp pads are radially spaced from said sonotrode and angularly offset from one another.
17 . An ultrasonic welding apparatus as set forth in claim 8 wherein said clamp pads have a textured pad surface.
18 . An ultrasonic welding apparatus as set forth in claim 8 wherein said clamp pads have a predetermined pad surface configuration used to imprint the workpiece.
19 . An ultrasonic welding apparatus as set forth in claim 17 wherein said textured pad surface includes a knurled pattern.
20 . An ultrasonic welding apparatus as set forth in claim 14 wherein said clamp pads are formed of a plastic material.