Abstract: A method includes receiving, during a vibration welding process, a set of sensory signals from a collection of sensors positioned with respect to a work piece during formation of a weld on or within the work piece. The method also includes receiving control signals from a welding controller during the process, with the control signals causing the welding horn to vibrate at a calibrated frequency, and processing the received sensory and control signals using a host machine. Additionally, the method includes displaying a predicted weld quality status on a surface of the work piece using a status projector. The method may include identifying and display a quality status of a suspect weld. The laser projector may project a laser beam directly onto or immediately adjacent to the suspect welds, e.g., as a red, green, blue laser or a gas laser having a switched color filter.

Abstract: A method includes receiving, during a vibration welding process, a set of sensory signals from a collection of sensors positioned with respect to a work piece during formation of a weld on or within the work piece. The method also includes receiving control signals from a welding controller during the process, with the control signals causing the welding horn to vibrate at a calibrated frequency, and processing the received sensory and control signals using a host machine. Additionally, the method includes displaying a predicted weld quality status on a surface of the work piece using a status projector. The method may include identifying and display a quality status of a suspect weld. The laser projector may project a laser beam directly onto or immediately adjacent to the suspect welds, e.g., as a red, green, blue laser or a gas laser having a switched color filter.

Abstract: A system includes a host machine and a status projector. The host machine is in electrical communication with a collection of sensors and with a welding controller that generates control signals for controlling the welding horn. The host machine is configured to execute a method to thereby process the sensory and control signals, as well as predict a quality status of a weld that is formed using the welding horn, including identifying any suspect welds. The host machine then activates the status projector to illuminate the suspect welds. This may occur directly on the welds using a laser projector, or on a surface of the work piece in proximity to the welds. The system and method may be used in the ultrasonic welding of battery tabs of a multi-cell battery pack in a particular embodiment. The welding horn and welding controller may also be part of the system.

Abstract: A joining operation for a stack of three metal sheets performed using only a single welding step, with access to only one sheet side being required. An inner sheet of the stack has formed therein a pair of bifurcated projections, wherein at least one first apex faces in one direction and at least one second apex faces in the opposite direction. First and second outer metal sheets are assembled with the inner sheet, wherein the first outer sheet abuts the at least one first apex, and the second outer sheet abuts the at least one second apex. A projection welding apparatus welds the sheets, using only access to the first outer sheet superposed the bifurcated projections, wherein a majority of the current flows through the second outer sheet.

Abstract: A method of controlling an indentation depth of an electrode into a metal substrate during formation of a weld includes selecting a weld force, current, duration, minimum indentation depth, and maximum indentation depth, contacting the substrate with the electrode to apply the force to the substrate, supplying the current to the electrode to initiate formation of the weld according to a first condition in which the depth is less than the minimum, a second condition in which the depth is greater than or equal to the minimum and less than or equal to the maximum, and a third condition in which the depth is greater than the maximum, and comparing the depth, minimum, and maximum. For the first condition, duration is changed. For the second condition, each of the force, current, and duration is maintained until the weld is substantially formed. For the third condition, current ceases to be supplied.

Abstract: A method of forming a resistance spot welding manufacture includes sandwiching a third metal layer between first and second metal layers to form a workpiece. The second layer has a surface defining an embossed region. The first layer has a first thickness, the third layer has a third thickness, and the second layer has a second thickness that is less than the first and third thicknesses so that a ratio of the first thickness to the second thickness is greater than about 2:1. The method includes positioning the workpiece between a first and second electrode so that the workpiece is disposed in electrically-conductive relationship with the first and the second electrodes, and applying an electrical current through the first electrode to concurrently melt the first and third layers and the surface at the embossed region to join the first and second layers to the third layer and form the manufacture.

Abstract: A resistance spot welding manufacture includes a first metal layer having a first thickness, a second metal layer having a faying surface defining an embossed region, wherein the second metal layer has a second thickness that is less than the first thickness so that a ratio of the first thickness to the second thickness is greater than about 2:1, a third metal layer sandwiched between the first metal layer and the embossed region, wherein the third metal layer has a third thickness that is greater than the second thickness, and a weld joint penetrating each of the first metal layer, the third metal layer, and the faying surface at the embossed region to thereby join each of the first metal layer and the second metal layer to the third metal layer. A method of forming a resistance spot welding manufacture is also disclosed.

Abstract: A method of monitoring and maintaining a weld cap which is executing successive resistance welds on a plurality of workpieces includes measuring a first weld indentation formed during a first resistance weld and measuring a second weld indentation formed during a second resistance weld. The measured first and second weld indentations are compared with a severe threshold. If either of the measured first or second weld indentations is greater than the severe threshold, an abnormal condition is signaled. The method may include tip dressing the weld cap based upon the signaled abnormal condition. The method may further include determining a degradation rate between the first resistance weld and the second resistance weld. The degradation rate is the time differential between the measured first and second weld indentations, and either a first or a second tip dressing schedule is chosen based upon the determined degradation rate.

Abstract: A resistance spot welding manufacture includes a first metal layer having a first thickness, a second metal layer having a faying surface defining an embossed region, wherein the second metal layer has a second thickness that is less than the first thickness so that a ratio of the first thickness to the second thickness is greater than about 2:1, a third metal layer sandwiched between the first metal layer and the embossed region, wherein the third metal layer has a third thickness that is greater than the second thickness, and a weld joint penetrating each of the first metal layer, the third metal layer, and the faying surface at the embossed region to thereby join each of the first metal layer and the second metal layer to the third metal layer. A method of forming a resistance spot welding manufacture is also disclosed.

Abstract: A method to diagnose a failed weld in a welding process includes monitoring a location of a weld created on a plurality of work pieces, diagnosing the weld as a failed weld based on said location with respect to a closest edge of one of the work pieces, and identifying said failed weld based on the diagnosing.

Abstract: A method of monitoring and maintaining a weld cap which is executing successive resistance welds on a plurality of workpieces includes measuring a first weld indentation formed during a first resistance weld and measuring a second weld indentation formed during a second resistance weld. The measured first and second weld indentations are compared with a severe threshold. If either of the measured first or second weld indentations is greater than the severe threshold, an abnormal condition is signaled. The method may include tip dressing the weld cap based upon the signaled abnormal condition. The method may further include determining a degradation rate between the first resistance weld and the second resistance weld. The degradation rate is the time differential between the measured first and second weld indentations, and either a first or a second tip dressing schedule is chosen based upon the determined degradation rate.

Abstract: A method of controlling an indentation depth of an electrode into a metal substrate during formation of a weld includes selecting a weld force, current, duration, minimum indentation depth, and maximum indentation depth, contacting the substrate with the electrode to apply the force to the substrate, supplying the current to the electrode to initiate formation of the weld according to a first condition in which the depth is less than the minimum, a second condition in which the depth is greater than or equal to the minimum and less than or equal to the maximum, and a third condition in which the depth is greater than the maximum, and comparing the depth, minimum, and maximum. For the first condition, duration is changed. For the second condition, each of the force, current, and duration is maintained until the weld is substantially formed. For the third condition, current ceases to be supplied.

Abstract: A joining operation for a stack of three metal sheets performed using only a single welding step, with access to only one sheet side being required. An inner sheet of the stack has formed therein a pair of bifurcated projections, wherein at least one first apex faces in one direction and at least one second apex faces in the opposite direction. First and second outer metal sheets are assembled with the inner sheet, wherein the first outer sheet abuts the at least one first apex, and the second outer sheet abuts the at least one second apex. A projection welding apparatus welds the sheets, using only access to the first outer sheet superposed the bifurcated projections, wherein a majority of the current flows through the second outer sheet.

Abstract: A method to diagnose a failed weld in a welding process includes monitoring a location of a weld created on a plurality of work pieces, diagnosing the weld as a failed weld based on said location with respect to a closest edge of one of the work pieces, and identifying said failed weld based on the diagnosing.

Abstract: A method of edge welding a plurality of workpieces particularly useful for minimizing edge deformation and reducing the electrode size, flange size, welding force and current load necessary to produce a given weld, including the steps of forming at least one distending projection along the edge of a first workpiece, securing the projection against a second workpiece and applying a force and current load to the projection so as to fuse a portion of the projection, and a system for performing the method, including a dedicated projection forming fixture, a resistance welding apparatus preferably having specialized electrodes and a controller communicatively coupled to the fixture and apparatus.

Abstract: Method and apparatus for detecting unacceptable misalignment of welding electrodes. An electrode-alignment station is positioned adjacent a welding station. A robot controls the movement of the electrodes, and occasionally moves the electrodes out of the welding station and into an electrode-alignment station. At the electrode-alignment station, the electrodes are closed on a fixture that transfers electrode-misalignment into movement of a plate that triggers an alarm if the misalignment is greater than a prescribed amount.

Abstract: Method and apparatus for detecting unacceptable misalignment of welding electrodes. An electrode-alignment station is positioned adjacent a welding station. A robot controls the movement of the electrodes, and occasionally moves the electrodes out of the welding station and into an electrode-alignment station. At the electrode-alignment station, the electrodes are closed on a fixture that transfers electrode-misalignment into movement of a plate that triggers an alarm if the misalignment is greater than a prescribed amount.

Abstract: A method of single sided spot welding includes the steps of providing a metal tube having a convex surface portion and providing a metal sheet for welding to the metal tube. The method also includes the steps of contacting the metal sheet with the convex surface portion of the metal tube and contacting the metal sheet with a welding electrode. The method further includes the steps of supplying power to the welding electrode for melting metal and solidifying the molten metal to form a weld nugget between the metal sheet and the metal tube.

Abstract: A method of single sided, spot welding includes the steps of providing a metal tube having a convex surface portion and providing a metal sheet for welding to the metal tube. The method also includes the steps of contacting the metal sheet with the convex surface portion of the metal tube and contacting the metal sheet with a welding electrode. The method further includes the steps of supplying power to the welding electrode for melting metal and solidifying the molten metal to form a weld nugget between the metal sheet and the metal tube.

Abstract: The present invention is for a method of lap joining two tubular members and then hydroforming the tubular assembly. An insert end of the first tubular member is inserted into a receiver end of the second tubular member to form a lap joint. A filler metal ring is placed about the outer periphery of the insert end so that it is adjacent the opening of the receiver end of the second tubular member. Heat is applied to braze or solder the lap joint, forming a tubular assembly. The tubular assembly is then hydroformed during which time a supplementary mechanical lock may be formed in the lap joint.