Abstract: A robot system includes: an articulated type robot which retains a processing tool at an arm tip end portion and which includes a plurality of drive units that drive a plurality of drive axes; and a robot controller which controls the drive units so as to control a relative position of the processing target and the processing tool and the robot controller includes: a torque information detection unit which detects torque information on the torques of the drive units; a contact position estimation unit which estimates, based on the change of tendency of a variation in the detected torque information of at least one of the drive units, a contact position in which the processing target and the processing tool make contact with each other; and a position compensation unit which compensates the target position of the robot based on the estimated contact position.

Abstract: A resistance spot welding method able to form a welded joint having delayed fracture resistance, includes, in order, applying a pressing force P1 (kN) to the plurality of steel sheets by welding electrodes while supplying a supplied current I1 (kA), while applying the pressing force P1, supplying a current Ic (kA) during a cooling time tc (s), repeating two times or more a pressure force raising and lowering cycle of supplying a supplied current I2 (kA) to the welding electrodes while applying a pressing force P2 (kN) to the plurality of steel sheets by the welding electrodes during a pressing time tf (s), then immediately applying a pressing force P3 (kN) during a pressing time ti (s), applying the pressing force P2 during the pressing time tf, and releasing the pressing force and ending the supply of current, satisfying 0?Ic<I1, 0.3?I2/I1<1.0, P2/P1?2, tf?0.2, P3<P2, and ti?0.2.

Abstract: Devices which shorten the time needed for the assembly of electrode capsules on welding grippers are provided. Such devices may have two stations for withdrawal of electrode capsules. The withdrawal stations may have a mirror-image arrangement with respect to a given intermediate plane and may be situated in a peripheral zone of the apparatus. Two guide ducts may house two respective rows of electrode capsules. Two prechambers can be provided, each one being arranged between the associated withdrawal station and an outlet end of the associated guide duct. A retractable stop pin may be mounted between each prechamber and the associated withdrawal station, said pin, when extracted, blocking an electrode capsule inside the withdrawal station. To transfer an electrode capsule from the prechamber to the associated withdrawal station, the apparatus may be provided with two positioning devices which can be selectively operated in order to accomplish this.

Abstract: A resistance spot welding method of squeezing a predetermined sheet combination by a pair of electrodes and passing a current while applying an electrode force to join the sheet combination includes: performing test welding; and performing actual welding after the test welding, wherein in each of the test welding and the actual welding, a current pattern is divided into two or more steps including a first current passage step and a second current passage step subsequent to the first current passage step, and, in the actual welding, a current that causes no expulsion is selected to perform welding by constant current control in the first current passage step, and adaptive control welding is performed from the subsequent second current passage step onward.

Abstract: When two high-strength steel sheets (1A, 1B) whose sheet thickness ratio={the sum of sheet thicknesses of the steel sheets}/{the sheet thickness of the thinner steel sheet (when they have the same thickness, the sheet thickness per one sheet)} is within a range of not less than 2 nor more than 5 and which both have tensile strength of not less than 780 MPa nor more than 1850 MPa are stacked to be subjected to resistance spot welding, a first welding step being pre-welding with a pressurizing force P1 kN and a welding current I1 kA and a second welding step being main welding with a pressurizing force P2 kN and a welding current I2 kA are performed, the pressurizing forces P1, P2 are set to a fixed pressurizing force P=P1=P2 all through the first welding step and the second welding step and are set within a range expressed by {0.5?P?3.

Abstract: A spot welding system (1) includes a welding pressure command generating unit (31) which generates a reference welding pressure command for a spot welding gun by applying pressure to workpieces to be welded between two electrode tips and at least one detective welding pressure command, an elastic displacement quantity deviation calculating unit (32) calculating, as an elastic displacement quantity deviation, a rotational position deviation between the rotational position of a servomotor when the reference welding pressure command is used and the rotational position of the servomotor when at least one detective welding pressure command is used, and an estimating unit (34) which estimates that there is an abnormality in the spot welding gun when the deviation between the elastic displacement quantity deviation based on the reference welding pressure command and at least one detective welding pressure command and the reference displacement quantity deviation is greater than a predetermined value.

Abstract: The invention provides a switching electrode which has a small variation in resistance value even when a large amount of current is repeatedly cut off and can carry a stable amount of current even when it is continuously used. In the invention, the switching electrode is used in a switch which includes a first switching electrode tip (21) and a second switching electrode tip (22), brings the first switching electrode tip (21) and the second switching electrode tip (22) into surface contact with each other to carry a current, and separates the first switching electrode tip (21) and the second switching electrode tip (22) to cut off the current. At least one of contact surfaces of the first switching electrode tip (21) and the second switching electrode tip (22) is a flat surface having an uneven portion.

Abstract: A spot welding apparatus according to is provided that includes an upper and lower moving unit, an upper welding gun, a left and right moving unit and a lower welding gun. In particular, the upper and lower moving unit includes a slide block that is provided at one side of an arm of a robot to move vertically by actuation of an actuator. The upper welding gun is mounted on the slide block and the left and right moving unit is installed at one side of the upper welding gun to horizontally move the upper welding gun by actuation of the actuator. Additionally, the lower welding gun is mounted to correspond to a lower side of the upper welding gun.

Abstract: A device is configured for changing electrode caps of a welding unit. The device includes at least one reserve unit configured to hold in reserve electrode caps which are required for welding with the welding unit. The device also includes a cap changing unit configured to change an electrode cap mounted on a welding tool for another electrode cap held in reserve in the reserve unit. The cap changing unit is configured to arrange the electrode cap demounted from the welding tool in the at least one reserve unit.

Abstract: A spot welding apparatus may include a fixed welding machine coupled to a fixing frame having a mounting portion mounted on an arm of a robot, a guide plate mounted on the fixing frame, one or more moving welding machines mounted to be selectively and slidingly movable along a longitudinal direction of the guide plate, and an operating unit configured to selectively move the moving welding machine.

Abstract: A twin spot welding apparatus includes a fixed welder in a fixed frame on a top of which a mounting unit of a robot arm is integrally formed, a guide plate mounted on the fixed frame, an angle control plate movably installed in the guide plate, a servo actuator mounted on the fixed frame to move the angle control plate on the guide plate, and a moving welder formed so that a slope of the moving welder may be controlled by an angle control unit on the angle control plate and formed in a moving frame so that, when the servo actuator and the angle control unit are operated, movement from the fixed welder and the slope of the moving welder are controlled so that a pitch and a slope between welding points of the fixed welder and the moving welder vary.

Abstract: A welding system for welding small precious metal firing tips to spark plug electrodes, such as ground and/or center electrodes. According to one embodiment, the welding system includes a firing tip storage assembly and a firing tip welding assembly, where the firing tip storage assembly uses pressurized gas introduced at the bottom of a part container to float or lift the firing tips so that the firing tip welding assembly can more easily acquire them with a vacuum-driven nozzle that also doubles as a welding electrode. The firing tip welding assembly is mounted to a robotic apparatus that can index or move the firing tip welding assembly between the firing tip storage assembly, a welding station and/or any other suitable positions.

Abstract: A method of welding two or more workpieces employing a motion-controlled electrode that reduces temperature and residual stresses at a workpiece-to-electrode interface is disclosed. During a first period of time, a first electrode force is applied to the workpieces to be welded, and a weld current is applied that causes heating of an associated workpiece-to-workpiece faying surface, the first electrode force being applied at a first electrode stroke. A temperature of the faying surface indicative of a weld nugget formation thereat is determined, and in response thereto the electrode force is reduced to a second level during a second period of time while maintaining a constant electrode stroke. During a third period of time, the electrode force is further reduced to a third level while simultaneously reducing the electrode stroke to a second level. Welding is stopped after the third period of time, resulting in a weld joint having reduced residual stresses and reduced likelihood of stress crack formation.

Abstract: A spot welding system including spot welding gun having a movable electrode driven by a servo motor, a counter electrode arranged facing it and with a multiarticulated robot, holding one of the welding workpiece and spot welding gun which moves welding workpiece and spot welding gun relative to each other and thereby make the movable electrode and the welding workpiece approach each other from a separated state or vice-versa, monitoring the current or torque of the servo motor, and detecting the surface position of the welding workpiece from the position of the movable electrode and the position of the multiarticulated robot when the trend of the current or torque changes. The precision of detection of the surface position of the welding workpiece by a movable electrode in a spot welding system can now be improved without lengthening the time required for detection of the surface position of the welding workpiece.

Abstract: A supply chute 11 has a nut send-in port 14 at its upper end, and is composed of an inclined chute 12 inclined obliquely downward, and a curved chute 13 coupled to the lower end of the inclined chute 12 and curved like an arc obliquely downward. A nut support mechanism 40 is disposed at a nut send-out port 15 provided at a terminal end of the curved chute 13, for supporting the nuts 60 being forwarded so that their bonding side 62 may be in an oblique downward position nearly orthogonal to the axial line of a guide rod 20. The inclined chute 12, the curved chute 13, the guide rod 20, and driving means 25 for moving the guide rod 20 back and forth in an oblique downward direction are mounted on a stand 22 installed rotatably on a support member 33 by way of a horizontal support shaft 35, and the support member 33 is coupled and fixed to a main body arm 2 of the bonding machine 1.

Abstract: A multiple welding gun system includes a plurality of welding guns, simultaneously performing welding operations, mounted to a robot arm of a welding robot and a pitch changing device as a space adjusting device disposed between the plurality of welding guns. The pitch changing device is configured to change a gun pitch so as to adjust a space between the welding guns by rotating one of the welding guns relative to other one of the welding guns to thereby move the welding guns closer to or separate from each other.

Abstract: For teaching a welding-point position for a robot, processing of a robot system includes first processing for moving a spot welding gun to a position at which movable and fixed electrodes pinch the welding point; second processing for extending the movable electrode toward a member to be welded by driving of a motor, detecting contact between the movable electrode and the member based on a torque command to the motor, and stopping the movable electrode after the contact is detected; and third processing for operating the robot toward the movable electrode to move the fixed electrode toward the member while maintaining the contact between the movable electrode and the member by the driving of the motor, detecting contact between the fixed electrode and the member based on a disturbance torque acting on a joint of the robot, and stopping the operation of the robot after the contact is detected.

Abstract: A positioning method of a spot welding robot, the spot welding robot having a movable electrode tip and an opposition electrode tip opposed to the movable electrode tip. The method sandwiches a work piece to be welded between the pair of electrode tips and includes driving the movable electrode tip towards the opposition electrode tip with a servo motor and stopping the movement upon contact based upon a prescribed current value. The method further includes measuring an open separation of two opposing tips between the movable electrode tip and the opposition electrode tip and moving the opposition electrode tip towards the moveable electrode tip based upon the preset value and the open separation of the two opposing tips.

Abstract: A method and a device produce a fleece of metallic fibers in a layer in which the metallic fibers are welded to one another to form the fleece. A welding process is repeatedly carried out with regard to a portion or section of the fleece. Such metallic fiber fleeces are used, in particular, for exhaust gas treatment units in the automobile industry.

Abstract: A system, method and apparatus for resource reallocation based on ambient condition data is disclosed herein. The system includes a planning module (102) for configuring plan data to include a primary sequence and an auxiliary sequence, a rule table (116) for storing the auxiliary sequence, an ambient condition receiver (124) for receiving the ambient condition data, and a routing processor (126) for accessing the rule table (116) to allocate an auxiliary sequence in place of a primary sequence in the event that particular ambient data is received.

Abstract: A positioning method of spot welding robot having: (A) moving a welding gun with a separation between an opposition electrode tip and a movable electrode tip kept open and larger than a preset plate thickness of a work piece so as to position the opposition electrode tip and the movable electrode tip on both sides of the work piece in a plate-thickness direction of the work piece, respectively, and temporarily positioning the opposition electrode tip at a stand-by position; (B) moving the movable electrode tip in a direction approaching toward the opposition electrode tip, monitoring the current value of the servo motor driving the movable electrode tip, and when the current value exceeds a prescribed value, determining that a distal end of the movable electrode tip has been brought into contact with the work piece, stopping a movement of the movable electrode tip and measuring an open separation of two opposing tips between the movable electrode tip and the opposition electrode tip that has been temporarily

Abstract: A method for open or closed-loop control of welding tong movement utilizes a welding tong drive having a primary and a secondary drive device. The primary drive device moves two welding tong limbs with welding electrodes toward a welding object from opposite sides. The welding tong limbs press onto the welding object with a predetermined compressive force. During actuation, the secondary drive device varies a spatial orientation of the welding tongs. In order to contact the welding object in a controlled manner, and to reliably acquire any deviations from specified spatial points during contacting, the welding tongs first approach a spatial point relative to the welding object. The welding tong limbs are held in a fixed spatial orientation during the approach. The secondary drive device is actuated until a welding tong limb contacts the welding object. The primary drive device then closes the welding tong limbs.

Abstract: The method for assembling a vehicle body according to an embodiment of the present invention includes: a floor assembly key-welding process for affixing a center floor and a rear floor together through a tack welding; a floor assembly respot process for forming a floor assembly by completely affixing a plurality of parts of the center floor and the rear floor together by spot welding; a vehicle body build-up key-welding process for forming an overall vehicle body frame by temporarily assembling a left side panel, a right side panel, a cowl, and a roof to the floor assembly; a vehicle body respot process for forming a vehicle body by completely affixing a plurality of parts of the left side panel, the right side panel, the cowl, and the roof by spot welding; and a front end assembling process for forming a final vehicle body by assembling a front end to the vehicle body by spot welding.

Abstract: A method of spot welding a sheet overlapped to a tube with a servomotor-driven electrode applying a clamping force to the sheet. Over a first clamping time interval, the clamping force is increased to a first force level, at which point a welding current is applied to weld the sheet and tube together for a welding time interval. The first force level is maintained for a second clamping time interval, after which the clamping force is reduced to a second force level over a third clamping time interval and is maintained for a fourth clamping time interval. The welding current is removed upon expiration of the welding time interval and the clamping force is simultaneously reduced over a fifth clamping time interval, after which the electrode is disengaged from the sheet. The reduction in clamping force during the welding cycle reduces cracking of the spot weld.

Abstract: The automatic robot spot welding apparatus includes a welding bench including clamping frames, which are uniformly arrayed and have receiving portions for the sparer grids, and have, at both ends of the welding bench, fixing plates for the guide tubes and the instrumentation tube which are inserted into the spacer grids; a robot moving on a running rail, which is arranged in parallel to the welding bench, and having a welding gun for welding the spacer grids with the guide and instrumentation tubes; guide tube electrodes for being inserted into the guide tubes for the spot welding; an instrumentation tube electrode for being inserted into the instrumentation tube; and a controller having an apparatus control block and a robot control block for controlling components based on a program stored therein.

Abstract: A robot controller and a welding timer coupled to each other by a dual-port RAM which is connected to data busses thereof, and Initial reference values of welding parameters are stored into a ROM of welding timer in same sequence as character strings of items. When power is turned on, character strings of items and values of the parameters are stored into a RAM of a robot, and both are displayed on a teaching pendant in same sequence. In teaching pendant, values of welding parameters are arbitrarily changed, and then stored into RAM of robot, and also into a RAM of the welding timer via dual-port RAM. A weld command given from the robot to welding timer via dual-port RAM, welding timer performs a welding process on basis of welding parameters which have been edited by teaching pendant and stored in RAM of the welding timer.

Abstract: A method of assembling a vehicular body includes the following operations: positioning a floor main and making a relative positioning between the floor main and a body side's lower section, by using a three-dimension general locator device standing on a floor, and positioning each of a right body side, a left body side and a roof rail and making the relative positioning between the body side's upper section and the roof rail, by using a front body side upper section locator jig and a rear body side upper section locator jig which are disposed on a ceiling and independent of each other in a forward-and-rearward direction of the vehicular body, and each of which is replaceable in accordance with a type of vehicle.

Abstract: The present invention relates to a welding apparatus and a welding method for a nuclear fuel skeleton which is fabricated by welding guide tubes for power control rods and a instrumentation tube for measuring fuel to spacer grids having a plurality of cells, into which fuel rods are inserted.

Abstract: A pogo welding apparatus especially for spot welding metal sheets at selected locations spaced away from their edges wherein the sheets are held in a temporary assembly with the selected locations engaged and separate programmable positioners move a primary (pogo) electrode and a backup electrode sequentially against opposite sides of the selected locations to spot weld the sheets at the selected locations in sequence. Various alternative programmable positioners, including robots of varying types, may be used to carry the electrodes. A multi head back-up electrode is adapted for efficient use of the apparatus and method in difficult to reach workpiece locations.

Abstract: A method of and device for automatically setting and updating a reference position of a welding tip of a servo spot welding gun to automatically compensate displacement of a distal end of a welding tip by abrasion thereof. A movable welding tip is moved towards a stationary welding tip to press the stationary welding tip until an estimated disturbance load reaches a fist threshold, and then moved in reverse direction away from the stationary welding tip until the disturbance load is reduced to a second threshold. The position of the movable welding tip when the disturbance load is reduced to the second threshold is set and updated as the reference position of an axis of the movable welding tip. The first threshold is set to be greater than a frictional force exerted on the axis of the movable welding tip in the motion towards the stationary welding tip, and the second threshold is set to be equivalent to the frictional force.

Abstract: The floor of a motor vehicle which is assembled in a floor assembly station is transported to a subsequent station using at least two welding robots on each lateral side of the floor assembly station. These welding robots are constituted into dual-purpose welding robots for performing both welding work and transporting work. After the assembling of the floor has been finished, the floor is supported at four lateral and longitudinal jack-up points through the workpiece receiving member by the cooperation of these dual-purpose welding robots, and is transported from the floor assembly station to the subsequent station.

Abstract: A welding method and system for welding a workpiece at weld locations includes a weld controller having control logic and stored data related to weld locations and workpiece dimensions. The weld controller is operable with a displacement sensor for monitoring the displacement between the electrodes of a weld gun. The control logic is programmed to generate a move signal based upon the stored data and the displacement between the electrodes. The weld controller also has stored data related to primary and alternate weld locations. The control logic is programmed to generate a fault signal based upon the stored data and a welding parameter such as the displacement between the electrodes. The weld controller provides a fault signal to the position controller to index the weld gun from a primary weld location to an alternate weld location when a comparison of the welding parameter to stored data related to the primary weld location indicates that the workpiece has been improperly welded.

Abstract: This invention relates to methods to control the resistance spotwelding process using an electric servomotor actuator to move the welding electrodes to the work and apply force to them. Measurements of actuator position, servomotor drive voltage, servomotor drive current, voltage across the welding electrodes, welding transformer primary current, welding transformer secondary current and power factor in the primary circuit of the welding transformer are used separately and in combination to determine various conditions such as identify defects in the welding machine, the electric cabling, the welding process and in the weld itself. Depending upon the defect found, the welding parameters are changed to overcome the defect, and/or the need for an additional weld is indicated and/or an error indication is generated.

Abstract: A method for sizing a weld tool for forming a resistance spot weld to fasten a joint having at least two sheet metal members is provided. The method includes the steps of providing a plurality of weld force curves, determining a governing metal thickness, determining a total thickness of the sheet metal members, determining a plurality of joint parameters, including a weld gap parameter, a thickness parameter, a strength parameter, an equalization parameter and a sheet stiffness parameter, using the plurality of joint parameters to select one of the plurality of weld force curves, and using the governing metal thickness and the selected weld force curve to calculate a weld force parameter.

Abstract: A welding voltage value Vf and a welding current value IF are respectively monitored by a detector during execution of arc welding in accordance with a robot operation program, indexes are calculated which show how far the monitored values Vf and If are deviated from a command welding voltage value Vc and a command welding current value Ic specified in the operation program, and it is decided that there is a possibility of occurrence of a defective weld in arc welding under execution, when the calculated index exceeds a preset threshold value. Then, the data for arc-welding execution conditions and execution results are cumulatively stored in a defective weld history data area provided in a memory in accordance with the line number and the statement of the line in the operation program for each line constituting the program, and the cumulatively-stored data is displayed on a screen.