20,322. Boult, A. J., [United Shoe Machinery Co.]. Sept. 28. Nailing.-Machines for making and inserting metal fasteners cut from a continuous strip of fastener material in leather goods and the like, particularly for use in the manufacture of boots and shoes, are provided with improved gripping, inserting, and severing means arranged so as positively and continuously to control, and positively to prevent premature severing of the fastener from the strip ; with improved work supporting and feeding mechanisms ; and with improved timing and arrangement of the various mechanisms so that the machine can operate at a very high speed. The invention is described as applied to a slugging-machine for heels, in which, also, are incorporated the several details and mechanisms described in the companion Specifications Nos. 28,925, 28,926. and 28,927, A.D. 1909. The main driving-shaft 14, Figs. 1 and 4, is located in a sleeve 22, which carries a swinging frame 24 having mounted to reciprocate in it the mechanism for forming and inserting fasteners of the same or different lengths. This mechanism consists of a reciprocating #-shaped cutter head 40, Fig. 1, to which are pivoted the outer ends of carriers 42. 44 for adjustable cutters 46, 48. The upper end of the bead 40 is connected by a sliding block and slot to an eccentric 60 on the main shaft 14. The inner ends of the carriers 42, 44 are pivotally connected to fork members 72, 74 of a slide 66, which is mounted in the head 40, and is reciprocated by a cam 34. The shape of this cam is such that the slide 66 is caused first to move relatively to the head 40, when the latter commences to descend, to force the cutters to grip the wire ; then to move with, and at the same rate as, the head, positively to hold the cutters from movement relatively to the head while they are being carried downwards to force the wire into the work ; then to move to cause the cutters to sever the wire ; and finally, to move to cause the cutters to separate so that they pass freely over the wire as the head moves upwards for the next stroke. In this way the control of the wire is positive throughout, and premature severing of the fastener is prevented. The machine is also fitted with a work-support which adjusts itself automatically to the thickness of the work, while the amount of drop it receives to permit the work to be fed is uniform. It is also fitted, for use when required, with an awl 162, which is controlled by a cam-groove in a disk 194, Fig. 2, mounted on a shaft 114. This mechanism is fully described in Specification No. 28,925, A.D. 1909. The cam disk 194 is also adapted to operate a sliding bolt 290, Fig. 4, which controls the engagement of a locking-pawl 340 with a ledge 348 upon the slide 66 to permit or prevent the insertion of fasteners. In the present invention, the timing and arrangement of the parts are such that the shaft 114 rotates once for every six revolutions of the main shaft 14, and the disk 194 is therefore arranged to be connected with its shaft by a clutch having six clutching points. This clutch is shown in Fig. 9, and consists of a hexagonal member 292 and a casing 294 secured respectively to the shaft 114 and to the disk 194. Between the clutch members are arranged rollers 296, which normally bear against portions of the casing 294 concentric with the shaft 114, but which, when moved, jam against eccentric portions of the casing and lock the two members of the clutch together. The rollers are actuated by a cage 298 loosely mounted on the shaft 114 and provided with an arm 300 adapted to be engaged by a fork member 306, Fig. 2, of a lever 304 pivoted to the machine frame. When the arm 300 is released by the member 306, a spring surrounding the casing 294 and bearin g against the arm 300 turns the cage 248 to effect the clutching movement of the rollers 296. The machine is arranged so that a rotatiou of the disk 194 through half a revolution places all the mechanisms controlled by it in operative relation to those mechanisms which are constantly operated from the main shaft, while the second half of the rotation of the disk restores the same mechanisms to their inoperative relations to the main shaft mechanisms. To insert several fasteners in succession it is therefore necessary to stop the disk 194 after it has rotated through half a revolution. To effect this, the arm 304 is furnished with a second fork member 308, which can be moved by treadle mechanism into the path of the arm 300. As the arm 300 reaches the member 308 the rotation of the roller casing 298 is arrested, and the clutch is broken. When this takes place, the strength of the born-controlling spring and the steepness of the particular operative part of the horn controlling cam tend to effect a premature dropping of the horn by turning the disk 194 about the shaft 114. To prevent this, a second roller clutch located in the casing 294 is provided. The work is fed by the engagement of a slotted plate 412, Fig. 4. yieldingly supported at the lower end of the swinging-frame 24 with a partially-inserted fastener. This plate is also moved down positively during the fastener-inserting movement of the cutters to drive home a fastener previously partly inserted.