GB781096A - Electrodes for attaching weld nuts - Google Patents

Abstract

781,096. Welding by pressure. OHIO NUT & BOLT CO. Jan. 3, 1955 [Jan. 21, 1954], No. 117/55. Class 83 (4). A welding electrode 10, Fig. 1, for positioning and welding a weld nut 21 or the like on a support member 19 includes a metal body portion having an end contact face 10a to engage the support member, a bore 11 extending into the body portion, and means for resiliently holding the outer end of a pilot member 12 beyond the contact face 10a. The pilot member has a portion 17 to locate a hole in the support member and a portion 20 to locate the nut 21. When the upper electrode descends to effect the welding operation, the pilot member is depressed against a spring 13 until the portion 17 is wholly within the bore 11. Wear or breakage of the pilot due to gripping by the support member is thus avoided. The pilot may be made of metal and be engaged by a portion electrically insulated from the upper electrode 22. Fig. 6 shows an alternative construction for locating and welding a nut 59 having an unthreaded aperture of the same diameter as the hole in the support member 57. The electrode body 25 is provided with a bore for water cooling purposes and a threaded coupling member 27 provides additional water cooling and permits attachment of an end portion 28. The pilot 52 is depressed by a pin 61 which may either be made of metal and mounted in a bush 62 of insulating material or be made of insulating material such as hard fibre. A pilot with two locating portions of different diameters the outer one of which is adapted to project beyond the nut as shown in Fig. 1 may also be used in this construction, the pin 61 being dispensed with. In a further modification (not shown) a spring-loaded pilot is mounted in an electrode insert adapted to be used with a quick-acting coupling.