Abstract:
The present invention relates to an ultrasonic soldering tool for soldering wires to a solder tab of an electrochromic device located between the layers of an insulated glass unit. The soldering tool includes an ergonomically designed handle and soldering tip head to increase operator comfort during use while also providing features to ensure that the surface of the insulated glass unit is not contacted by the soldering tip. One embodiment of the invention provides an automatic feed soldering tool which may have a soldering tip with a trough to create an ideal solder joint. The invention also includes a clamp for securing a wire to a substrate in a correct position while serving as a guide for the soldering tool to provide further protection from errant contact between the soldering tip and the insulated glass unit. The invention also includes a method of creating an ideal solder joint.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    The present application claims the benefit of the filing date of U.S. Provisional Application No. 61/736,801, filed Dec. 13, 2012, and U.S. Provisional Application No. 61/764,780, filed Feb. 14, 2013, the disclosures of which are hereby incorporated herein by reference. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    A thin film device e.g. an electrochromic device, is deposited on a glass substrate which is incorporated into an insulating glass unit (IGU). This patent application addresses the process, equipment, and materials for soldering electrical interconnections to bus bars on the device. 
         [0003]    Electrochromic glazings include electrochromic materials that are known to change their optical properties, such as coloration, in response to the application of an electrical potential, thereby making the device more or less transparent or more or less reflective. Typical prior art electrochromic devices include a counter electrode layer, an electrochromic material layer which is deposited substantially parallel to the counter electrode layer, and an ionically conductive layer separating the counter electrode layer from the electrochromic layer respectively. In addition, two transparent conductive layers are substantially parallel to and in contact with the counter electrode layer and the electrochromic layer. 
         [0004]    Materials for making the counter electrode layer, the electrochromic material layer, the ionically conductive layer and the conductive layers are known and described, for example, in United States Patent Publication No. 2008/0169185, incorporated by reference herein, and desirably are substantially transparent oxides or nitrides. When an electrical potential is applied across the layered structure of the electrochromic device, such as by connecting the respective conductive layers to a low voltage electrical source, ions, such as Li+ ions stored in the counter electrode layer, flow from the counter electrode layer, through the ion conductor layer and to the electrochromic layer. 
         [0005]    In addition, electrons flow from the counter electrode layer, around an external circuit including a low voltage electrical source, to the electrochromic layer so as to maintain charge neutrality in the counter electrode layer and the electrochromic layer. The transfer of ions and electrons to the electrochromic layer causes the optical characteristics of the electrochromic layer, and optionally the counter electrode layer in a complementary EC device, to change, thereby changing the coloration and, thus, the transparency of the electrochromic device. 
         [0006]    As used herein, the term “insulated glass unit” (IGU) means two or more layers of glass separated by a spacer (metal, plastic, foam, resin based) along the edge and sealed to create a dead air space, “insulated space” (or other gas, e.g. argon, nitrogen, krypton) between the layers. The IGU comprises an interior glass panel and an EC device, described further herein. 
         [0007]    Electrical connection to the electronic device is achieved by thick film silver (Ag) solder tabs external to the adhesively bonded spacer. The solder tabs are electrically connected to thick film Ag bus bars which contact conductive device layers inside the IGU. Wires delivering electrical power are soldered to the bus bars which terminate in solder tabs exterior to the spacer. The space between the two glass substrates where the attachment to the solder tab is made is narrow and may be less than about 6 mm high. 
       SUMMARY OF THE INVENTION 
       [0008]    The invention relates to an ultrasonic soldering tool and method of soldering. The soldering tool according to one aspect of the disclosure has a handle with an ultrasonic soldering element secured to it by at least one rib. The ultrasonic soldering element can be adapted to receive a soldering tip that may operate between parallel substrates of an insulated glass unit, preferably through incorporation of a trough in the soldering tip head. 
         [0009]    The rib of the soldering tool according to one aspect of the disclosure can be adapted to incorporate additional interconnected elements. One of the additional interconnected elements may be a bubble level which can be mounted substantially parallel to the soldering tip head to accurately reflect the angular pitch of the head during operation of the soldering tool. 
         [0010]    The soldering tool according to one aspect of the disclosure may use a trigger to directly activate power to the tool. The trigger could also send a signal to digital timer circuitry to activate power to the tool. The digital timer circuitry desirably includes a switch to activate power to the ultrasonic soldering element, an indicator LED on the soldering tool, and an audible signal generator which may indicate when the soldering cycle is complete. 
         [0011]    The soldering tool according to one aspect of the disclosure is an automatic feed soldering tool that can supply solder to the desired solder joint location. The automatic tool can have interconnected elements mounted to the at least one rib including a solder roll, drive rollers, a gear motor, and a solder feed tube. 
         [0012]    The automatic soldering tool according to one aspect of the disclosure may have the solder roll mounted to the at least one rib, the drive rollers mounted to the solder roll, and the solder feed tube mounted to the drive rollers. The gear motor may be mounted to and adapted to rotate the drive rollers. The drive rollers may then transfer solder from the solder roll through the solder feed tube. The solder may emerge from the feed tube at the soldering tip head. 
         [0013]    The gear motor according to one aspect of the disclosure may supply a fixed volume of solder to the soldering head. In other embodiments, the gear motor may be adjustable to modify the volume of solder supplied. 
         [0014]    The soldering tool according to one aspect of the disclosure may have a soldering tip head with a trough. A solder feed port may extend from an exterior surface of the tip into the trough. The feed port may be adapted to transport solder from the feed tube into the trough. Another aspect of the disclosure may use a solder well adapted to receive and melt the solder from the feed tube before it enters the solder feed port. 
         [0015]    Another aspect of the disclosure is a soldering tip, which can be an elongated member having a head with a trough. The trough may be adapted to surround a wire during soldering and can be oriented substantially horizontally to the soldering element. A solder feed port may extend from an exterior surface of the soldering tip into the trough and is preferably sized to transport solder via capillary action. According to one aspect of the disclosure, the trough can have a parabolic profile. The soldering tip may also have a solder well to melt solder before it enters the solder feed port. 
         [0016]    The method of creating a solder joint according to one aspect of the disclosure desirably uses a clamp. The clamp may have a housing, an upper jaw, a lower jaw, a sled, and a spring. The housing may have a chamber to receive the sled which may be free to move in at least one dimension within the chamber. The spring can also be located within the chamber. The upper jaw can be connected to the housing, and the lower jaw can be connected to the sled. The spring may exert a force against the sled and housing to maintain the upper jaw and lower jaw in close proximity to each other. 
         [0017]    According to one aspect of the clamp, there can be a stub extending from the housing and a beam extending from the sled. The beam may be free to move along a path defined by a slot in the housing. The beam and stub may extend in similar directions so an operator can adjust the position of the beam relative to the stub with one hand, thereby changing the proximity of the upper jaw and lower jaw. Another aspect of the disclosure is the lower jaw may have a protective material attached to it. 
         [0018]    The method of ultrasonically soldering a wire to a solder tab according to one aspect of the disclosure desirably includes the steps of preparing a wire to be soldered, cleaning the solder tab, positioning the wire on the solder tab; fixing the wire in position with a clamp; positioning a soldering tool to solder the wire; ultrasonically soldering the wire to the solder tab which can result in a solder joint formed in a space between the layers of an insulated glazing unit. 
         [0019]    The method of ultrasonically soldering a wire in another aspect may include forming an ideal solder joint by delivering a precise volume of solder to the solder joint, thereby creating a solder joint having a desired pull strength using minimal solder. In some embodiments, solder may be pre-applied to the wire before soldering to help ensure that a precise volume of solder is used. In other embodiments, solder may be delivered during the soldering process through use of an automatic feed soldering tool. 
         [0020]    The quality of the solder joint can be controlled according to one aspect of the disclosure by monitoring the volume of solder supplied to the joint and the duration of contact between the soldering tool and the wire. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0021]    A more complete appreciation of the subject matter of the present invention and the various adavantages thereof can be realized by reference to the following detailed description, in which reference is made to the accompanying drawings: 
           [0022]      FIG. 1  is an illustrative embodiment of a soldering tool of the present invention. 
           [0023]      FIG. 2  is a top view of the soldering tool of  FIG. 1 . 
           [0024]      FIG. 3  is a sectional view of the soldering tool of  FIG. 1 . 
           [0025]      FIG. 4A  shows one embodiment of a soldering tip according to the present invention in various stages of manufacture. 
           [0026]      FIG. 4B  is a perspective view of the soldering tip of  FIG. 4A . 
           [0027]      FIG. 5  is an enlarged view showing a soldering tip head according to one embodiment of the current invention. 
           [0028]      FIG. 6  is an isolated view of the soldering tip in operation. 
           [0029]      FIG. 7  shows a soldering tool, clamp, wire, and IGU in use according to one embodiment of the current invention. 
           [0030]      FIG. 8  shows a clamp according to one embodiment of the present invention. 
           [0031]      FIG. 9  shows an alternative embodiment of a clamp according to the present invention. 
           [0032]      FIG. 10  is an isolated view showing a clamp securing a wire to an IGU. 
           [0033]      FIG. 11  is an enlarged view showing the soldering tip, wire, and clamp of  FIG. 7 . 
           [0034]      FIG. 12  is an enlarged view of an ideal solder joint. 
           [0035]      FIG. 12A  is a sectional view of the ideal solder joint of  FIG. 12 . 
           [0036]      FIG. 13  is a side and front view of a wire with pre-formed solder attached. 
           [0037]      FIG. 14  is a flow chart depicting the process of soldering a wire in accordance with one embodiment of the current invention. 
       
    
    
     DETAILED DESCRIPTION 
       [0038]    Although the invention disclosed in this application has been described with reference to particular embodiments, it is to be understood that these embodiments are merely illustrative of the principles and applications of the present invention. It is therefore to be understood that numerous modifications may be made to the illustrative embodiments and that other arrangements may be devised without departing from the spirit and scope of the present invention as defined by the appended exemplary claims. 
         [0039]    Overall Process Flow 
         [0040]    Thin films and other structures are deposited on the glass device substrate by methods known to those skilled in the art as described in, for example, U.S. Pat. Nos. 5,321,544; 5,404,244; 7,327,610; 7,593,154; and 8,482,837. 
         [0041]    Thick film silver (Ag) paste is applied to create bus bars which traverse at least a portion of the device and terminate in solder tabs. The paste is dried and fired forming solderable bus bars. In some embodiments, the bus bars are fired at 380 to 420 deg. C. 
         [0042]    In some embodiments, the bus bars can be on a single glass sheet, on a multilayer (2 or more) laminated structure, or part of an IGU. In some embodiments, a multiwire cable is attached to the IGU spacer, and individual wires are routed to the appropriate solder tabs. In some embodiments, a controlled amount of solder is affixed directly to each wire that will subsequently be soldered to a thick film Ag solder tab. In some embodiments, the wire is positioned on the solder tab and held in place by a clamp or other mechanism so that glass edges cannot be damaged and the extent of solder flow is controlled. In some embodiments, the soldered area is coated followed by application of secondary IGU seal. Finally, the thin film IGU is tested. 
         [0043]    Referring now to  FIG. 1 , a soldering tool  10  in accordance with the current invention is shown. In some embodiments, the handle  11  of the soldering tool  10  is shaped to fit into the palm of an operator&#39;s hand. The handle  11  in the embodiment shown generally has the shape of a rectangle and is composed of two pieces that are substantially mirror images of each other. The pieces are mirrored at about line A-A as shown in  FIG. 2 . The pieces can be joined by screws, a press fit, glue, welding, or similar manner. In the embodiment shown, the assembled handle  11  is approximately 5 inches in length, 2 inches in width, and 1 inch deep. In some embodiments, the handle  11  is made of a lightweight material such as plastic, carbon fiber, Kevlar, resins, aluminum, or other composite materials. 
         [0044]    The handle  11  has a trigger  12  for activating the power to the soldering element  30  in the front of the handle  11 . In some embodiments the trigger  12  faces the same direction as the soldering tip  40  to provide comfortable operation of the soldering tool  10 . The trigger  12  can be located at the top of the handle  11 , adjacent to the platform  13 , where a user&#39;s index finger is positioned when gripping the handle  11 . 
         [0045]    A platform  13  is connected to the top of the handle above the trigger  12  in the embodiment shown. In some embodiments the platform  13  can be a rectangular plank that is molded as part of the handle  11  to reduce manufacturing costs. In other embodiments, the platform  13  may be manufactured separately, then attached to the handle  11  by screwing, gluing, welding, or a similar method of securing two objects together, and depending, of course, on the materials used. The platform  13  can extend beyond the perimeter of the top of the handle  11  as necessary to provide an adequate base for the soldering element  30  to be secured to. The size of the platform  13  is therefore determined by the soldering element  30  to be used in the soldering tool  10 . In some embodiments, the platform  13  is wider than the diameter of the outer casing  15  of the soldering element  30  to allow the ribs  14  to extend from the platform  13  and around the outer casing  15 . In some embodiments, the platform  13  is at least as long as the segment of the outer casing  15  of the soldering element  30  that has a uniform thickness. 
         [0046]    The soldering element  30  in the embodiment shown in [ FIG. 1 ] is an ultrasonic soldering element, e.g. a MBR Electronics GmbH Ultrasonic Soldering System USS-9210. The soldering element  30  in this embodiment has a generally cylindrical outer casing  15 . The outer casing  15  can be composed of plastic with low thermal conductivity, thereby remaining cool to the touch during operation of the soldering element  30 . In the embodiment shown, a sleeve  16  extends from the outer casing  15  and the sleeve  16  contains the soldering tip  40 . The sleeve  16  can be metal to withstand the heat generated by the heating apparatus (not shown) that is part of the soldering element  30 . Power is supplied to the soldering element  30  by the wire running from the handle  11  to the back of the soldering element  30 . The outer casing  15  of the soldering element  30  in the embodiment shown is approximately 10 inches long with a diameter of 2 inches. The sleeve  16  has a diameter of approximately 0.25-1 inch and extends beyond the front of the outer casing  15  by approximately 5.25 inches. The soldering element  30  is positioned on top of the platform  13  and is surrounded by ribs  14  extending from the platform  13 , and up the sides of the soldering element  30 . The ribs  14  themselves reach toward the medial line of the soldering tool (line A-A in  FIG. 2 ). Thus, when the two halves of the handle  11  are joined the free ends of the ribs  14  contact, or nearly contact, the corresponding ribs  14  from the other half such that they can be secured to each other, thereby locking the soldering element  30  in place. In one embodiment, screws are used to secure the halves together. Alternative methods of attaching the halves of the ribs  14  together can be used including welding, gluing, press fits, and the like. The ribs  14  in the embodiment shown have a length of approximately 1.25 inches but can range from 1 inch to 4 inches depending on the thickness and orientation of the ribs  14 . In some embodiments the ribs  14  are spaced approximately 0.75-1.5 inches apart from each other with approximately 1-2 inches of the soldering element  30  extending beyond the foremost and rear ribs  14 . In other embodiments the soldering tool  10  may have only two ribs  14 ; one at the front and one at the back of the platform  13 . The ribs  14  on each half of the solder tool can be parallel to the rib adjacent to it or, alternatively, some of the ribs  14  can converge to provide further stability. In some embodiments the ribs  14  may be replaced by a solid piece that engulfs the soldering element  30  when the two halves are joined. 
         [0047]    In some embodiments, the ribs  14  can serve as a mounting apparatus for alternative features of the soldering tool  10 . For example, a bracket  57  may be incorporated to support or act as a platform  13  to mount any additional interconnected elements in the design of the soldering tool  10  and molded as part of a rib. In one embodiment, additional interconnected elements can include a solder roll  54 , precision roller drive gear motor  56 , and solder feed tube  53  as shown in [ FIG. 1 ]. 
         [0048]    A cross sectional view of the soldering tool  10  can be seen in  FIG. 3 . The handle  11  may have walls  33 ,  37 ,  300 , which define the cavity of the handle  11 , extending perpendicularly from the plate  35  toward the medial line of the soldering tool  10 . In some embodiments the front and back walls  35 ,  37  are substantially parallel to each other; and the bottom wall  300  is substantially parallel to the platform  13 . In some embodiments each half of the handle  11 , including the walls  33 ,  37 ,  300 , platform  13 , and ribs  14  are preferably formed as a solid piece through a molding process. In other embodiments the handle  11  can be made of separate pieces that compose one or more elements of the tool and then assembled through use of screws, welding, glue, or other appropriate means depending on the material used to manufacture the soldering tool  10 . In some embodiments the cavity of the handle  11  may contain a weight to counterbalance the mass of the soldering element  30  and give the tool a more balanced feel. 
         [0049]    In some embodiments the front  35  and back wall  37  have notches to allow power wires  17 ,  18  to enter and exit the cavity of the handle  11  for connecting the power supply (not shown) to the switch  32  and then to the soldering element  30 . 
         [0050]    In some embodiments the front wall  33  is shaped to allow the trigger  12  to move when pressed by an operator, thereby activating a momentary contact switch  32  to power the soldering element  30 . In the embodiment shown in  FIG. 3 , a spring  34  is compressed against the trigger anchor  31  when the trigger  12  is squeezed, forcing the momentary switch  32  to complete the circuit and supply power to the soldering element  30 . When the trigger  12  is released the spring  34  recoils pushing the trigger  12  to its original position, the circuit is broken, and the power to the soldering element  30  is turned off. 
         [0051]    In other embodiments, the switch  32  is a low-amperage low-voltage contact switch that serves as an input to digital timer circuitry located in the power supply. In some embodiments, the digital timer circuitry activates power to the soldering element  30 , turns on an LED (not shown) located on the under the bubble level  70  (see  FIG. 7 ) and activates an audible signal generator that signifies to the operator that the soldering cycle is complete. In some embodiments, the power to the soldering element  30  is provided by the digital timer circuitry for approximately 4-6 seconds. The timer may then turn off the LED approximately 1-3 seconds after turning off the power to the soldering element. In some embodiments, the audible signal is active while power is being supplied to the LED and turns off simultaneously with the LED. These are indications to the operator that the soldering process is complete and the soldering tip may be removed from the soldering joint. 
         [0052]    In other embodiments, different types of switches can be used with the same effect such as a pushbutton, toggle, rocker, slide, rotary switch, etc. The switch  32  must be sized to withstand the power requirements of the soldering element  30 . Therefore, the soldering element selected will determine the switch that may be used. A soldering element that requires more power will require a switch that is able to withstand a higher power draw. 
         [0053]    In the embodiment shown in  FIG. 3 , anchors  36  for the switch  32  and the trigger  12  are formed as part of the plate  35  in the cavity of the handle  11 . The anchors  36  can be shaped to accommodate the switch  32  and the trigger  12 . The anchors  36  may also be used to join the two halves of the handle  11  together. In some embodiments, the two halves are placed together whereby the anchors  36  align and a screw is inserted from the exterior of the handle  11  into both anchors  36 , preventing the halves from separating. In other embodiments the anchors  36  could be adapted to fit together via a press fit, gluing, welding, or other appropriate method depending on the material used to manufacture the soldering tool  10 . 
         [0054]    In some embodiments, the handle  11  can have grip pads attached to the sides to increase the comfort of the operator during use. 
         [0055]    In some embodiments, the platform  13  is adjacent to the front  33  and back  37  walls and is oriented substantially from the front to the back of the soldering tool  10 . The platform  13  may provide a base to which the soldering element  30  is secured. The platform  13  can have a thickness from top to bottom ranging from about 0.25 to 2 inches. In the embodiment shown, the platform  13  has a thickness of about 0.3 to 0.75 inches. The platform  13  must be of sufficient thickness to withstand the weight of the soldering element  30  and the vibration generated during operation of the ultrasonic soldering tool  10 . 
         [0056]    In some embodiments, the outer casing  15  of the soldering element  30  is secured to the platform  13  by the ribs as shown in  FIG. 1 . In some embodiments the soldering element  30  is powered by a wire  17  that runs from the switch  32  in the cavity of the handle  11 , through the notch in the back wall  37 , and into the back of the soldering element  30 . In other embodiments the wire  17  can be routed from the switch  32 , through the platform  13 , and into the side or bottom of the soldering element  30 . The power supplied in the wire  17  is determined by the requirements of the soldering element  30 . In some embodiments the power can range from 5-15 Watts for the ultrasonic requirements and 80 Watts for the heater apparatus. 
         [0057]    In some embodiments, the ultrasonic vibration element, e.g. a sonotrode, is integrated in the outer casing  15 . In some embodiments the sonotrode can align with the tip shaft  38 , which may be co-axial with the sleeve  16 . The tip shaft  38  can have a range of diameters from about 0.3 to 0.6 inches. In some embodiments, the sleeve  16  extends from the front of the outer casing  15  and may contain the heating apparatus, e.g. a ceramic heater (not shown). The tip can be inserted through the sleeve  16  and into the shaft  38  to use the soldering tool  10 . 
         [0058]      FIG. 4  shows a soldering tip  40  in accordance with the current invention. In some embodiments the tip can be manufactured from a stock blank tip  41  supplied by the manufacturer of the soldering element  30 . In some embodiments the soldering tip  40  is composed of metal such as steel, iron, aluminum, or the like with a diameter of approximately 0.5 to 1 inch and a length of approximately 7.4 to 14 inches. 
         [0059]    The soldering tip  40  has a tail  42  at its distal end which is sized to fit within the tip shaft  38  of the soldering element  30  (see  FIG. 3 ). Those skilled in the art will appreciate that the tail  42  must be of sufficient diameter relative to the diameter of the tail shaft  39  to allow ultrasonic sound waves (not shown) to exert pressure on the tail  42  without significant blowby, but at the same time, not such a snug fit as to cause unnecessary friction between the walls of the tail shaft  39  and the tail  42 . In some embodiments, the tail  42  has a diameter of approximately 0.3 to 0.6 inches and a length of approximately 0.15 to 0.5 inches with a face at the back end transverse to the front-back direction of the soldering tip  40 . The sonotrode of the soldering element  30  emits high frequency sound waves which build up pressure against the face of the tail  42  and forces the soldering tip  40  to vibrate back and forth in the direction of oscillation  401  shown in  FIG. 4B . 
         [0060]    In some embodiments, the tail  42  is adjacent to the shoulder  43 . The shoulder  43  may fit within the tip shaft  38  but may be wider than the tail shaft  39  (see  FIG. 3 ). When the soldering tip  40  is vibrating back and forth the shoulder may contact the ledge  301  of the tail shaft  39  which prevents the tail  42  from contacting and damaging the sonotrode. In some embodiments, the shoulder  43  has an approximate diameter of 0.5 to 1 inch and an approximate length of 0.5 to 1 inches. The shoulder  43  may have retaining grooves  44  cut into its sides to secure the tip in place during operation which in some embodiments may be 0.15 to 0.35 inches long, 0.25 to 0.5 inches wide, and 0.05 to 0.2 inches deep. 
         [0061]    In some embodiments of the soldering tip  40 , the spacer  45  is proximal to the shoulder  43 . The spacer  45  can have a diameter ranging from approximately 0.2 to 0.6 inches and a length of approximately 4 to 5.5 inches. The spacer  45  may be of sufficient length to ensure that the heat transferred to the soldering tip body  46  is not conducted from the body  46 , through the spacer  45  and shoulder  43 , and to the tail  42 , thereby causing thermal expansion of the tail  42  and preventing its free movement. 
         [0062]    In some embodiments, the tip body  46  is proximal to the spacer  45 . The diameter of the body  46  can range from about 0.6 to 1 inches and the length can range from about 2 to 4 inches. The body  46  may be positioned substantially within the sleeve  16  of the soldering element  30  during operation of the soldering tool  10 ; with the front end of the body  46  protruding past the front of the sleeve  16  (see  FIG. 1 ). In some embodiments, the body  46  is heated by the heating apparatus of the soldering element  30  located in the sleeve  16 . The heating apparatus may be a ceramic heater that is constantly powered to maintain a constant temperature unlike the ultrasonic feature of the soldering tool  10  which is only powered when the trigger  12  is pressed by the operator. 
         [0063]    In some embodiments, the neck  47  is proximal to the body  46  and may have a smaller diameter than the body  46  such that the head  48  and neck  47  can fit in the narrow space between the layers of the IGU. In some embodiments, the height of the neck  47  can range from about 0.2 to 0.6 inches. The bottom of the neck  47  may remain parallel to the bottom of the body  46  to allow the operator to smoothly maneuver the tool back and forth while the bottom of the soldering tip  40  is in contact with the clamp  80  during operation. (see  FIG. 11 ). The neck  47  can have a length ranging from about 0.75 to 3 inches. 
         [0064]    In some embodiments, the head  48  is proximal to the neck  47  and is created by cutting off about 0.2 to 0.5 inches of the blank soldering tip, then undergoing connecting and machining operations as described below. In other embodiments, the head  48  may be manufactured distinctly from the rest of the tip and then attached to the neck  47  via a screw, welding, or other appropriate means depending on the material used to create the soldering tip  40 . When a cut off portion  400  is used to create the head  48 , it may be tooled to create a flat surface on one side to mate with the proximal end of the soldering tip  40  and secured into place via welding, screwing, gluing, or other appropriate means depending on the material used to create the soldering tip  40 . In some embodiments, the cut off portion  400  may extend below the bottom of the neck  47  as shown in  FIG. 4A . 
         [0065]    In some embodiments, the cutoff portion  400  is then tooled to create a head  48  having a rectangular shape with dimensions ranging in size from about 0.01 to 0.3 inch wide by 0.2 to 0.5 inches long by 0.35 to 1.5 inches deep. In some embodiments, the neck  47  and head  48  are created during the same tooling process. In other embodiments, the head  48  and neck  47  are created by separate manufacturing processes and the head  48  is later secured to the soldering tip  40  by material appropriate methods. 
         [0066]    In some embodiments, the face is located on the bottom of the head  48 . In other embodiments, the face can be oriented at any angle on the soldering head  48 . 
         [0067]    In some embodiments, a trough  49  is located on the face. The trough  49  can extend from one side of the face to the other, thereby creating a horizontal trough  49 . The horizontal orientation of the trough  49  can improve the ergonomic feel of the soldering tool  10 . The downward orientation of the trough  49  allows the tip to be maneuvered at a low height above the solder joint such that the tip can fit in the narrow space between the layers of the IGU. The trough  49  allows the head  48  of the soldering tip  40  to surround the wire to be soldered, thereby creating a high quality solder joint as explained below. It is believed that the size of the trough  49  is influenced by the size of the wire to be soldered. 
         [0068]    In some embodiments, the trough  49  can have a range of dimensions from about 0.1 to 1 inch long and 0.1 to 1 inch deep. In the embodiment shown in  FIG. 4A , the trough  49  is approximately 0.05 inches long by 0.5 inches wide by 0.5 inches deep resulting in a trough  49  with a volume of approximately 0.0125 cubic inches. Although a range of values have been given for the head  48  and trough  49 , it should be appreciated by those skilled in the art that the dimensions could be adjusted to accommodate wires of a larger or smaller diameter, or to create a solder joint that uses more or less solder. The trough  49  can be open on both sides and can have a parabola shape to produce fillet shaped edges of the solder joints  63  as shown in  FIG. 6 . In some embodiments, the shape of the trough  49  reduces the likelihood for the wire to be damaged by the soldering tip  40  during the soldering process because the trough  49  makes it unlikely that the soldering tip  40  will contact the wire. 
         [0069]    The trough  49  in the embodiment shown in  FIG. 5  has been sized to create an ideal solder joint for a wire of a known thickness. In some situations, an ideal solder joint has smooth fillets on both sides of the wire having a radius approximately equal to that of the wire, with a smooth and shiny surface. 
         [0070]    In other embodiments, an ideal solder joint is one with consistent fillets on the sides of the wire and also meets or exceeds the required pull strength testing of the joint. The application for which the IGU may be used can used to determine the pull strength needed. Some applications may require higher pull strength than others, e.g. high wind load environments. In some embodiments, a parallel pull test shows strengths of approximately 25N to 90N. 
         [0071]    In some embodiments, it is desirable to create an ideal solder joint while using minimal solder which may be about 0.0001 to 0.0005 cubic inches of solder. 
         [0072]    A larger trough will create a solder joint with higher pull strength but will require a greater volume of solder than is used in a smaller trough. A larger trough will also increase substrate heating during the soldering process because the soldering tip will need to remain in close proximity with the IGU for a longer period of time to melt the solder which could lead to damage as a result of thermal stress near the edge of the glass substrate. A smaller trough will reduce the necessary amount of solder but will reduce the pull strength of the solder joint. Reducing the amount of solder used can have significant economic benefits when an expensive solder (e.g. 97/3 Indium Silver) is used. An ideal solder joint allows the solder to completely surround the wire as shown in  FIG. 6 . The ideal solder joint  63  also has a fillet shape  122  (see  FIG. 12 ) on the ends as well as the sides (see  FIG. 12A ) to reduce weak joints that are formed by perpendicular edges. 
         [0073]    In one alternate embodiment, the neck  47  and head  48  have a solder feed port  51  extending from inside the trough  49 , through the head  48 , and emerging on the upper side of the neck  47  as shown in  FIG. 5 . In some embodiments, the solder feed port  51  can increase in diameter before it breaches the top of the neck  47  to create a solder well  52 . Solder  60  can be placed into the solder well  52  where it is melted before it flows through the feed port  51  and into the trough  49 . In some embodiments, the diameter of the feed port  51  can be sized to utilize capillary action as the mechanism to transport solder through the feed port  51  and into the trough  49 . The size of the feed port  51  may range from about 0.01 to 0.05 inches in diameter and 0.1 to 0.5 inches in length. The solder well  52  can range from about 0.05 to 0.1 inches in diameter and 0.1 to 0.3 inches in length. The solder well  52  and the head  48  can be heated to approximately 230° C.+/−10° C. to melt the solder in the well  52 . The temperature required to melt the solder is dependent on the type of solder used. In some embodiments, eutectic 97/3 Indium Silver solder, available from Indium Corporation of America, is used which has a melting point between about 140° and 150° F. The heat is supplied by the heating apparatus of the soldering element  30 . The heat travels via thermal conduction through the soldering tip  40 , heating the soldering well  52 . In some embodiments, the solder  60  can be deposited in the solder well  52  from the solder feed tube  53  of the soldering tool  10 . 
         [0074]    One embodiment of the soldering tool  10  may include a bubble level  70  as shown in  FIG. 7 . The bubble level  70  may aid a user in properly orienting the alternate soldering tool during operation to prevent accidental contact with any surfaces of the IGU. The bubble level  70  in the embodiment shown is mounted to a surface formed by the ribs  14  of the alternate soldering tool  74 . In some embodiments, the level can be permanently secured to the surface by screwing, gluing, or other appropriate ways. In other embodiments, the level  70  may be temporarily secured to the alternate soldering tool  74  to train the operator to properly use the soldering tool. When the operator is deemed to be of sufficient skill the bubble level  70  may be removed thereby reducing the weight and size of the alternate soldering tool  74  while at the same time improving the visibility of the soldering tip  40  during operation. In some embodiments, the level  70  is oriented from the front to the back of the alternate soldering tool  74  and is substantially parallel with the tip body  46  such that the bubble level  70  reflects the horizontal pitch of the tip body  46 . 
         [0075]    Returning now to  FIG. 1 , in some embodiments, a solder roll  54 , solder drive rollers  55 , precision roller drive gear motor  56 , and solder feed tube  53  are combined with the soldering tool  10  of the present invention to create an automatic feed ultrasonic soldering tool. In some embodiments, using an automatic feed soldering tool can eliminate the step of pre-applying solder to a wire before soldering, thereby reducing the effort required to prepare the wire to be soldered. 
         [0076]    In the embodiment shown in  FIG. 1 , a bracket  57  is created as part of the front rib  14  to accommodate a solder roll  54  and allow it to freely rotate when in operation. The same bracket  57  may be adapted to also support a precision roller drive gear motor  56  and solder feed tube  53 . In some embodiments, the gear motor  56  turns rollers (see  FIG. 3 ) which are positioned to tangentially pull the solder off the roll  54  and push the solder down the feed tube  53  to be delivered at the soldering head  48 . The gear motor  56  may be activated by the same trigger  12  as that used to power the soldering element  30 . The gear motor  56  can deliver a precise amount of solder to the soldering head  48  to ensure that no solder is wasted during the formation of each solder joint, thus resulting in the creation of a solder joint with minimal solder used. In some embodiments, the gear motor  56  is adjustable to allow an operator to supply more or less solder to the soldering head  48  each time the gear motor  56  is powered. 
         [0077]    In some embodiments, the gear motor  56  may continuously supply solder to the soldering head  48  for the entire duration the trigger  12  is pressed. In other embodiments, the gear motor  56  may supply solder for a fixed period of time during each trigger  12  press, then refrain from providing solder while the soldering tip continues to form the solder joint and completes the soldering process. 
         [0078]    In some embodiments, the bubble level is combined with the automatic feed soldering tool to allow the operator to observe the pitch of the soldering element while utilizing the benefits of the automatic feed soldering tool. 
         [0079]    Turning now to  FIG. 8 , one embodiment of the clamp  80  in accordance with the current invention is shown. In some embodiments, the clamp  80  has an upper jaw  81  and a lower jaw  82 . The upper jaw  81  can have an anchor  83  with two arms  85  extending from the elevated region of the anchor  83 . The lower region of the anchor  83  below the arms  85  is the bumper  84 . In some embodiments, the bumper  84  helps properly align the aperture  86  in the arms  85  with the wire and the solder tab  61  that the wire may be soldered to. The aperture  86  may be properly aligned when the arms  85  are inserted into the space between the layers of the IGU until the bumper  84  contacts the outer edge of the glass substrate  72  (see  FIG. 10 ). 
         [0080]    The anchor  83  can have a concave depression  100  on its upper surface to ensure proper clearance while operating the soldering tool. In some embodiments, the depression  100  may also be used to support and guide the sleeve  16  of the soldering tool  10  while in use. The radius of the concave depression  100  may be larger than the sleeve  16  radius of the soldering tool  10 . In some embodiments the radius of the depression  100  can be about 0.25-0.5 inches. It is believed that in some embodiments, having a larger radius influences the soldering tool  10  to remain in the center of the anchor  83  during operation, but does not unnecessarily restrict it to a fixed spot. In some embodiments, the arms  85  remain connected by a membrane as they begin to extend away from the anchor  83  (see  FIG. 10 ) which may have a valley  87  similar to the concave depression  100  of the anchor  83  and may support the soldering tip  40  during operation of the soldering tool  10 . However, the valley  87  is elevated slightly above the depression  100  thereby creating a lip  101 . In some embodiments, the lip  101  can prevent an operator from inserting the soldering tip  40  too deep into the IGU, thereby contacting and damaging the IGU spacer  73 . As the soldering tip  40  moves along the valley  87  during the soldering process, the sleeve  16  of the soldering tool  10  may contact the lip  101 , thereby preventing further insertion (see  FIG. 11 ). 
         [0081]    The arms  85  of the upper jaw  81  extend away from the anchor  83  with the bottom surface of the arms  85  able to contact the glass substrate  72  of the IGU  71 . In some embodiments, the arms  85  can have a width of about 0.2 to 0.5 inches and a length of about 0.4 to 0.75 inches while the height of the arms  85  may be less than the size of the space between the layers of the IGU  71 . In some embodiments, the height of the arms  85  may range from about 0.02 to about 0.075 inches. The arms  85  define a void between them where a wire may be located to be soldered. The underside  806  of the arms  85  may also have an aperture  86  for the wire that allows the bottom surface of the arms  85  to contact the IGU  71  while securing the wire to be soldered in place during operation. The depth and width of the aperture  86  are determined by the size of the wire to be soldered. In some embodiments, the depth and the width of the aperture  86  are equal and can range from about 0.02 to about 0.05 inches. The aperture  86  can be oriented horizontally to match the positioning of the wire on the IGU  71 . 
         [0082]    In some embodiments, the anchor  83  of the upper jaw  81  may be secured to the clamp housing  88  using screws, glue, welding, or other appropriate method based on the composition of the housing  88  and jaw  81 . In some embodiments, the upper jaw  81  may be manufactured from a material that is temperature resistant, non-stick, and non-scratching, e.g. Rulon LR, a PTFE plastic produced by Saint-Gobain Performance Plastics. In other embodiments, the upper jaw  81  can be created as part of the clamp housing  88  and consist of the same material. 
         [0083]    In some embodiments, the clamp housing  88  can have a substantially rectangular shape with dimensions ranging from about 0.3-0.6 inches deep by about 0.5-1 inch wide by about 2-4 inches high as shown in  FIG. 8 . In some embodiments, the top end of the housing  88  can be adapted to receive and secure the upper jaw  81 . The housing  88  can have a central opening that defines a chamber  89  for the jaw sled  800 , guide rods  801 , and guide spring  802 . In some embodiments, the chamber  89  does not extend all the way through the clamp housing  88 . The chamber  89  can have sufficient depth to accommodate the other components of the clamp  80 , but still have a substantially solid back portion to increase the overall strength and prevent distortion of the clamp  80  during operation. In some embodiments, the chamber  89  can have dimension ranging from about 0.2 to about 0.5 inches deep by about 0.25 to about 0.75 inches wide and about 1 to about 3 inches high. 
         [0084]    In some embodiments, the chamber  89  may include one or more guide rods  801  that extend the length of the chamber  89  for the spring  802  and jaw sled  800 . The guide rods  801  may be composed of steel, aluminum, or other similar rigid material. In some embodiments, at least one guide rod  801  is positioned toward the outside of the chamber  89  and at least one rod  801  is positioned toward the center of the chamber  89 . The outer guide rod  801  can keep the sled  800  properly aligned as it moves up and down the chamber  89  during operation. The center guide rod  801  can keep the spring  802 , as well as the sled  800 , properly aligned. The spring  802  can exert a force on the bottom of the chamber  89  and the sled  800  to provide the compressive force necessary for the upper  81  and lower jaw  82  to press against the IGU  71  during operation and remain in place. In some embodiments the spring  802  can be compressed with a small enough force that an operator can attach and remove the clamp  80  from the IGU  71  with one hand e.g. about 3-5 lbs. of compressive force. 
         [0085]    In some embodiments, the back of the clamp housing  88  can have a stub  103  extending away from the housing  88  as shown in  FIG. 10 . The stub  103  can have a concave underside shaped to accommodate an operator&#39;s finger when squeezing the clamp  80 . In the embodiment shown in  FIG. 10 , the stub  103  is located below the slot  105  for the beam  104 . 
         [0086]    In some embodiments, the housing  88  can be manufactured substantially by a 3D printing process and require only minor secondary operations at assembly. One of the components that may need to be attached to the housing  88  during the secondary operations is the cover  804 . The cover  804  can be attached to the front of the housing  88  and can secure the sled  800  and flange  803  inside the chamber  89 . In some embodiments, the cover  804  can be press fit into place. In other embodiments, the cover  804  can be attached via screws, glue, welding, or other appropriate means depending on the material selected. 
         [0087]    In some embodiments, the lower jaw  82  can have a top surface  805  that opposes the underside  806  of the arms  85 . The top surface  805  may be substantially flat to maintain uniform contact with the IGU  71 , thereby avoiding uneven pressure on the glass substrate  72 . In some embodiments, the top surface  805  can have a rectangular shape with dimensions ranging from about 0.2 to about 0.5 inches wide by about 0.3 to about 0.75 inches deep. 
         [0088]    The top surface  805  can be supported by the lower jaw base  807  which connects the top surface  805  with the jaw flange  803 . In some embodiments, the lower jaw  82  can be manufactured using the same 3D printing process and material used to create the clamp housing  88 . In other embodiments, the lower jaw  82  and flange  803  can be created from polymers, metals, or other solid materials. In the embodiment shown in  FIG. 8 , the flange  803  has screw holes  810  to attach the flange  803  to the sled  800 . The flange can have a groove in the back side to mate with the sled tongue  808 . In still other embodiments, the lower jaw  82  may have an additional protective material placed on its top surface  805  (e.g. rubber, silicone or similar) to prevent damage to the substrate  72  or accidental movement of the clamp  80  during operation. In some embodiments, the material may be a 1/16″ soft rubber pad attached with a pressure sensitive adhesive. 
         [0089]    In some embodiments, the sled  800  is placed within the chamber  89  but remains free to move up and down the chamber  89 . However, the spring  802  may exert a force to keep the sled  800  at the top of the chamber  89  when at rest. The shape of the sled  800  can follow the inner contours of the chamber  89  which in some embodiments is rectangular. The sled  800  can be shorter in length than the chamber  89  to allow the sled  800  to travel up and down during operation of the clamp  80 . A shorter sled  800  in comparison to the chamber  89  can allow greater travel distance but may require a longer spring  802  to fill the void created by having a shorter sled  800 . In some embodiments, the sled  800  may have cut outs to fit around the spring rod  801  and outer guide rods  801 . 
         [0090]    In some embodiments a beam  104  extends from the back of the sled  800  and through the slot  105  in the back of the housing  88  as shown in  FIG. 10 . In some embodiments, the top of the beam  104  may have relief cuts  106  to create friction between an operator&#39;s appendage and the beam  104  when in use. In other embodiments, other materials can be applied to the top of the beam  104  to improve the grip such as rubber or similar materials. In still other embodiments, the top of the beam  104  may have a plain, solid surface. The beam  104  can be fixed to the sled  800  such that if the beam  104  moves up and down the path defined by the slot  105 , the sled  800  will move correspondingly. In some embodiments, the beam  104  can be aligned with the stub  103  and separated by a distance such that an operator can grip the stub  103  with a finger and the top of the beam  104  with the thumb of the same hand and squeeze the two together, thereby separating the upper  81  and lower  82  jaws to apply and remove the clamp  80  from the IGU  71 . 
         [0091]    The front of the sled  800  is substantially flat with a tongue  808  extending forward that runs the length of the sled  800  from top to bottom which may assist in properly aligning the groove of the flange  803  on the sled  800 . In some embodiments, the front of the sled  800  can have various screw holes  809  for connecting the flange  803  to the sled  800  in more than one position, thus making the clamp  80  adjustable. 
         [0092]      FIG. 9  shows a wide opening clamp  90  that is adapted to be used with thick laminates or triple pane IGU configurations. The embodiment shown depicts screw holes  809  that allow discrete changes in the alignment of the flange  803  on the sled  800 . It should be understood that the screw holes  809  shown are merely exemplary and a greater or lesser quantity of holes could be included to increase or decrease the different locations the flange  803  can be positioned at. In other embodiments of the adjustable clamp  90 , the flange  803  can be secured in any position along the sled  800  and need not align with specific locations. 
         [0093]    As discussed previously, the ideal solder joint is one that achieves or surpasses the required pull strength while using minimal solder. In some embodiments, it is desirable to have a solder joint  63  where the solder  60  completely surrounds the wire  62  (see  FIG. 6 ). This may not happen if the wire  62  is in contact with the solder tab  61 . Therefore, in some embodiments it is desirable for the wire  62  to remain separated from the solder tab  61  during soldering. The size of the gap between the wire  62  and solder tab  61  which may be filled by solder  60  is determined based on the size of the wire  62  and the pull strength desired from the solder joint  63  with a larger joint  63  resulting in higher pull strength. 
         [0094]    In some embodiments, to maintain the spacing  121  between the wire  62  and the solder tab  61 , the wire insulation  110  functions as a spacer as shown in  FIG. 12 . Prior to soldering, the insulation  110  is peeled back or removed to expose a length of the wire  62  where it will be soldered (see  FIG. 11 ) which in some embodiments can range from about 0.05 to 0.3 inches. Exposing the wire  62  can be done before the soldering process begins which may save time during the soldering operation. In some embodiments, the insulation  110  thickness can range from about 0.005 to 0.025 inches. In some embodiments, the wire insulation  110  can be used as the spacer during soldering in combination with the automatic feed soldering tool described above. 
         [0095]    In other embodiments, solder  60  may be pre-applied to the exposed wire  62  to prevent the wire from contacting the solder tab  61  during soldering, as shown in  FIG. 13 . Pre-applying solder to the wire may have the additional benefit of supplying a precise amount of solder for each solder joint. In addition it is believed that pre-applied solder may result in a defined final position of the wire once the solder joint has been created, thereby resulting in consistent pull off strength of the joint. 
         [0096]    In some embodiments, a solder ribbon  131 , ranging from about 0.1 to 0.25 inches wide, is swaged or crimped around the exposed wire. In other embodiments, the solder is cast around the wire. In some embodiments, the radius of the outside of the solder ribbon  131  is equal to the outside radius of the wire insulation  110  such that the solder  131  is tangential to the solder tab  61  when the wire  62  is placed on the glass substrate  72  of the IGU  71 . 
         [0097]    In some embodiments, a wire with solder ribbon  131  can be soldered to the solder tab  61  by utilizing the soldering tip  40  with a trough  49  of the current invention. The trough  49  can surround the solder ribbon  131 , thereby melting the solder and forming the solder joint  63  in a parabola shape, which may be desirable in some embodiments. 
         [0098]      FIG. 14  is a flow chart depicting a method of the soldering process in accordance with one embodiment of the present invention. In some embodiments, the process begins in step one  141  wherein a wire is prepared to be soldered. The preparation may include separating or removing the insulation from the wire in predefined locations such that the exposed portions of wire align with the solder tabs of the IGU. 
         [0099]    In some embodiments, step two  142  is commenced by cleaning the solder tab  61  with a fiber glass pen which may remove the oxidized top layer off the silver solder tab  61  by a controlled abrasive action. In other embodiments, a fine-wire stainless steel brush may be used. 
         [0100]    In some embodiments, the step three  143  is positioning the prepared wire on the solder tab  61 . In some embodiments, the operator may manually hold the wire in place until step four  144  is completed. 
         [0101]    In some embodiments, step four  144  entails fixing the wire in position on the solder tab  61  using the clamp  80  of the current invention. In some embodiments, the operator may hold the wire  62  in place with one hand while operating the clamp  80  with the other hand. The jaws  81 ,  82  of the clamp  80  may be opened by the operator and the bumper  84  may be placed in contact with the outer edge of the glass substrate  72  of the IGU  71 . The operator may then adjust the clamp  80  such that the arms  85  of the clamp  80  surround the exposed wire  62  to be soldered, ensuring that the wire  62  is aligned with the aperture  86  of the arms  85 , then release the beam  104  and stub  103 , thereby allowing the jaws  81 ,  82  of the clamp  80  to close, fixing the wire  62  in place. 
         [0102]    In some embodiments, step five  145  is the positioning the soldering tool  10  so the neck  47  of the soldering tip  40  contacts the valley  87  of the clamp  80  to maintain the lateral positioning of the soldering tool  10  during soldering. In some embodiments, the operator may visually confirm that the trough  49  of the soldering tip  40  is aligned with the wire  62 , then place the tip  40  in position such that the trough  49  is surrounding the wire  62  to be soldered. 
         [0103]    In some embodiments, step six  146  may be when the operator activates power to the soldering tool  10 , thereby ultrasonically soldering the wire  62  to the solder tab  61 . In some embodiments, the operator may visually inspect the solder joint  63  as it is being formed. The operator may then deactivate the power to the soldering tool  10  after the joint is formed. In some embodiments, the power is supplied to the soldering tip for 4-6 seconds to create the solder joint. 
         [0104]    In some embodiments, the operator may need to manually apply solder at the solder joint location to create the solder joint. In other embodiments, such as when the automatic soldering tool is used, the solder may be supplied by the soldering tool, thus relieving the operator of the duty to manually supply solder at the solder joint location. 
         [0105]    In some embodiments, step seven  147  may be when the operator removes the soldering tool  10  from the soldering location by raising the soldering tip  40  until the trough  49  no longer surrounds the solder joint  63 . The operator may then move the soldering tool  10  away from the IGU  71 . 
         [0106]    In some embodiments, the solder joint may freeze during step eight  148  which occurs when the operator removes the soldering tool  10  and puts the tool aside. In some embodiments, the joint may freeze in about 2-3 seconds. 
         [0107]    Step nine  149 , in some embodiments, may be when the operator removes the clamp  80  from the IGU  71 . The operator may grip the beam  104  and the stub  103  and squeeze them together, thereby opening the jaws  81 ,  82  so the clamp  80  may be removed. 
         [0108]    In some embodiments, the process described in  FIG. 14  may be repeated as many times as necessary to solder any number of joints desired on an IGU.