An apparatus includes a welding electrode and a holder with a primary electrical connection for carrying a welding current. The electrode and the holder may separate easily due to a weak interference fit of the primary electrical connection. Bare hands may provide sufficient force for separation. The electrode and the holder may be configured for self-alignment. A quick-release mechanism may prevent unintentional dislodgement of the electrode from the holder and include a rotation-resistant device for preventing electrode rotation. A secondary electrical connection may be included to supplement or replace the primary electrical connection. A workpiece clamping force, traditionally intended for clamping the electrode to a workpiece, may also be utilized to enable the secondary electrical connection.

An apparatus includes a welding electrode and a holder with a primary electrical connection for carrying a welding current. The electrode and the holder may separate easily due to a weak interference fit of the primary electrical connection. Bare hands may provide sufficient force for separation. The electrode and the holder may be configured for self-alignment. A quick-release mechanism may prevent unintentional dislodgement of the electrode from the holder and include a rotation-resistant device for preventing electrode rotation. A secondary electrical connection may be included to supplement or replace the primary electrical connection. A workpiece clamping force, traditionally intended for clamping the electrode to a workpiece, may also be utilized to enable the secondary electrical connection.

A welding gun and a welding method with which it is possible to reduce the wait time for loading a component and to decrease tact time. The welding gun is a welding gun for resistance-welding components to a workpiece successively, and comprises a first holding portion and a second holding portion for holding a component. The first holding portion and the second holding portion are each switchable to an abutment-enabling position for causing a component to abut against a workpiece, or to a loading-enabling position for loading the component. The first holding portion and the second holding portion are switchable such that when the first holding portion is in the abutment-enabling position, the second holding portion is in the loading-enabling position, and when the second holding portion is in the abutment-enabling position, the first holding portion is in the loading-enabling position.

In a method of assembling a lower electrode mechanism, after a support tube and an electrode holder are integrally assembled, a cylindrical assembly case is inserted into the support tube from the bottom to align an elongated hole of the support tube with an elongated hole of the assembly case to assemble them. The rod assembly is inserted into the tube from the upper part of the electrode holder. The lower end of the rod of the rod assembly is placed to a position visible through the elongated hole of the support tube. A protruding bar is inserted into the support tube, the base end of the protruding bar is fixed to the lower end of the rod, and the slide sensor is attached to the support tube while the distal end of the protruding bar and detector of the slide sensor are connected.

In a method of assembling a lower electrode mechanism, after a support tube and an electrode holder are integrally assembled, a cylindrical assembly case is inserted into the support tube from the bottom to align an elongated hole of the support tube with an elongated hole of the assembly case to assemble them. The rod assembly is inserted into the tube from the upper part of the electrode holder. The lower end of the rod of the rod assembly is placed to a position visible through the elongated hole of the support tube. A protruding bar is inserted into the support tube, the base end of the protruding bar is fixed to the lower end of the rod, and the slide sensor is attached to the support tube while the distal end of the protruding bar and detector of the slide sensor are connected.

A welder having first and second electrodes configured to clamp and weld a fastener to a workpiece at an opening in the workpiece, wherein the first electrode is configured to move in a direction transverse to a clamping direction to center the fastener with the opening. The welder can carry out a method of aligning and welding an internally-threaded nut to a panel at an opening in the panel. The method includes the steps of: centering the opening in the panel relative to a first electrode using a tapered guide pin that extends into the opening; centering the nut relative to the opening using the tapered guide pin; clamping the nut and panel between the first electrode and a second electrode; and welding the nut to the panel by passing current through the nut and panel from one of the electrodes to the other electrode.

A welder having first and second electrodes configured to clamp and weld a fastener to a workpiece at an opening in the workpiece, wherein the first electrode is configured to move in a direction transverse to a clamping direction to center the fastener with the opening. The welder can carry out a method of aligning and welding an internally-threaded nut to a panel at an opening in the panel. The method includes the steps of: centering the opening in the panel relative to a first electrode using a tapered guide pin that extends into the opening; centering the nut relative to the opening using the tapered guide pin; clamping the nut and panel between the first electrode and a second electrode; and welding the nut to the panel by passing current through the nut and panel from one of the electrodes to the other electrode.

A cap dispenser for a welding gun includes a sleeve that slidably receives a drawer that is configured to house a column of weld caps. The cap dispenser also includes a spring that cooperates with a slide block that is arranged in the drawer. The spring urges the slide block toward an aperture in the drawer that is configured to receive a welding gun electrode.

A welding gun includes first and second movable arms, and first and second welding electrodes. The first and second movable arms are movable upward and downward. The first and second welding electrode are disposed respectively on the first and second movable arms. The welding gun is capable of performing a first mode in which the first and second welding electrodes are brought into contact with one side of a workpiece to weld the workpiece, and a second mode in which the workpiece is sandwiched by the first and second welding electrodes to weld the workpiece. The first and second welding electrodes are pivotally supported by the first and second movable arms, respectively. Each of the first and second welding electrodes has a rotatable roller shape. The first movable arm includes a first slide mechanism configured to allow the first welding electrodes to slide to below the second welding electrode.

Provided is a spot welding machine able to perform spot welding in which the desired nugget size is formed while suppressing spatter even if the strengths or thicknesses of the metal sheets change, the machine comprising: a pair of electrode tips, a pair of pressing members arranged around the tips, a first power supply, first and second drive mechanisms, and a pressing force control part, wherein the tips and the pressing members are respectively arranged facing each other so as to be able to sandwich a set of sheets between them, the first drive mechanisms give pressing forces pressing the tips against the sheets, the second drive mechanisms give pressing forces pressing the pressing members against the sheets, and the control part independently controls the pressing forces given by the first and second drive mechanisms.