Patent GB-1267829-A (GB)
Title: Friction welder and friction welding method
IPC: B23K20/12
Filed: 1969-11-13
Abstract: 1,267,829. Seaming. GENERAL MOTORS CORP. 13 Nov., 1969 [25 Nov., 1968], No. 55617/69. Heading B5K. [Also in Division B3] In a friction welding machine having first and second workpiece holders there is provided a first drive means for relatively rotating the first holder with respect to the second holder to form a weld, and a second drive means to subsequently relatively rotate the first holder with respect to the second holder to form a further weld. As shown in Fig. 1, a friction welding machine has a headstock 10 and tailstock 12 fastened to a base 13. A power unit 14, Fig. 2, has first and second hydraulic drive motors 16, 18. The first drive motor 16 drives a flywheel 34 mounted on the spindle 36 via suitable gear means 26, 30 coupled by an endless chain 32, and a one-way clutch 28 which permits the drive gear 26 to overrun the motor in the drive direction. The gear 30 drives an annular hub 40 which is connected to the outer casing of a selectively engageable clutch 42 which is preferably electrically operated. The second drive motor 18 similarly drives a second flywheel 44 which is also coupled to a selectively engageable clutch 52. Spindle 36 is coupled to a second spindle 54 which extends through a housing 58, Fig. 3, and has at its free end an annular flange 60 to which is fastened a head assembly 62. The head assembly has a top plate having a dove-tail groove to slidably receive the dove-tail of a cross-slide 74. The cross-slide has clamping jaws 78, Fig. 6, biased by springs 80 into clamping engagement with a rectangular workpiece 86. A piston 94, is hydraulically operated, as shown in Fig. 3, and has a connected piston-rod 96 which is coupled by pivoted links to plate (66), Fig. 4 (not shown), to thus effect the selective lateral sliding of the cross-slide 74 with respect to the rest of the head assembly. The head assembly is balanced in all positions of the cross-slide by a counterbalance (124), Fig. 8 (not shown). The tail-stock 12 includes a carriage 132 which is slidably moved by a piston and cylinder means. An hydraulic motor 142 drives a hollow spindle 152 by a speed-reducing drive comprising worm gear 146, gear 148, spindle drive 150. The spindle 152 extends through and is connected to a quill 154. A collet support 156 having a cone-shaped collet 158 and clamping jaws 160 are provided at the end of the quill to receive a cylindrical workpiece 162. Spring plungers 165 urge the collet and collet support in different axial directions to provide a light initial gripping force. The final gripping force is provided when an axial force is applied to the end of the workpiece 162 when it engages the workpiece 86. The spindle is moved axially by means of hydraulic controls leading into chambers 174, 175, provided on either side of the quill 154. An additional support, Fig. 10 (not shown), comprising an upright having a rest (180) may be employed for workpiece 162. Both workpieces are driven in the same direction 86 at 2500 r.p.m. and 162 at 200 r.p.m., the first workpiece by the flywheel 34. Preferably the motor 16 is slowed down or stopped and flywheel 34 continues the weld cycle until a weld is complete and while the welded workpieces are being removed, motor 18 drives the associated flywheel 144 up to a speed for welding of a further set of workpieces. By means of the cross-slide 74 the relative sliding of the workpieces is accomplished to permit heating of all of the interface areas. A flash removing tool assembly, Fig. 14 (not shown), is described And comprises a rotatable cutter wheel (190) driven by a belt or chain drive (188). In a modification of the friction welding machine, Fig. 12 (not shown), the cross-slide 74 in the head assembly has been eliminated and there is provided a motor mechanism (224) for laterally moving the headstock (206) by means of slide plates (223) slidably mounted by tracks or ways (222). A further flash removing tool (Fig. 13) (not shown) is described and has a fixed cutter of carbide or ceramic fixed to a slide which is slidably mounted on ways and is operated by a control cylinder between operating and non- operating positions.