Patent ID: 7556188
Filing Date: 2009-07-07
Classification: B23K

Abstract:
1. A clamping device comprising: a backing member including an upper face adapted to press against two work pieces to be welded together, with the backing member further including a bottom face; and a clamping unit including a rod extending through the backing member and having an exposed upper portion and an exposed lower portion, with the upper portion being adapted to extend through a narrower portion of a welding gap between the work pieces into a wider portion of the welding gap, with the lower portion including an abutting portion formed thereon, with an elastic element being mounted between the bottom face of the backing member and the abutting portion to bias the backing member to press against the work pieces, with the upper portion including a hooked section having a first width smaller than a width of the narrower portion of the welding gap allowing the hooked section to extend through the narrower portion into the wider portion of the welding gap between the work pieces, with the hooked section having a second width perpendicular to and larger than the width of the narrower portion of the welding gap, with the rod being tumable to a position in which the second width of the hooked section presses against the work pieces under action of the elastic element, and with the abuffing portion including a ring having a circumference, with the ring including a central opening and two diametrically opposed slots each extending radially outward from an inner periphery defining the central opening, with two catch plates extending from the circumference of the ring and respectively engaged with two upper edges of the backing member, with the lower portion of the rod including a lower end having a width parallel to the second width of the hooked section, with the width of the lower end of the lower portion being larger than a diameter of the central opening and smaller than an overall length of the slots, with the rod being movable in a vertical direction when the width of the lower end of the lower portion is aligned with the slots, and with the rod being not movable in the vertical direction when the rod is turned to a position where the width of the lower end of the lower portion is not aligned with the slots.