Currently, the art of welding plastic or resinous parts incorporates a variety of techniques including ultrasonic welding, heat welding, and, most recently, Through Transmission Infrared (TTIr) welding.
TTIr welding employs infrared light passed through a first plastic part and into a second plastic part. TTIR welding can use either infrared laser light or incoherent infrared light in the current art. Infrared laser light in the current art can be directed by fiber optics, waveguides, or light guides through the first plastic part and into a second plastic part. This first plastic part is often referred to as the transmissive piece, since it generally permits the laser beam from the laser to pass therethrough. The second plastic part is often referred to as absorptive piece, since this piece generally absorbs the radiative energy of the laser beam to produce heat in the welding zone. This heat in the welding zone causes the transmissive piece and the absorptive piece to be melted and thus welded together. However, control of the laser can be difficult and currently requires manual adjustment of the output of the laser source to achieve the desired laser heating effect. This manual adjustment is performed on a trial and error process and can be very laborious and time consuming.
According to the principles of the present teachings, it is desirable to control the output of the laser source to insure proper welding and, more particularly, it is desirable to control the output of the laser source through the use of closed loop feedback control.
Further areas of applicability will become apparent from the description provided herein. It should be understood that the description and specific examples are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure.