Patent GB-1193568-A (GB)
Title: Key Cutting Machine with Preselected Depth Gauging.
IPC: B23D36/00
Filed: 1968-12-09
Abstract: 1,193,568. Shearing; work guides. CURTIS NOLL CORP. 9 Dec., 1968 [15 May, 1968], No. 58409/68. Heading B3W. A key-cutting device comprises a support body, a vertically and transversely movable key blank support plate carried by the support body, means securing the plate to the body and guiding it to define a path of movement for the plate, a key-cutting means carried by the body and movable into cutting engagement with a key blank carried by the plate, a depth gauge assembly carried by the plate and abutment means carried by the body in the path of movement of the depth gauge assembly and sequentially engageable with each of a series of gauging surfaces on the assembly to selectively limit vertical movement of the plate into key-cutting position. As shown, Fig. 1, a spring-biased punch 35 is actuated by pivoting a handle 31 on a support body 21. An upright portion 26 of the body carries a vertically adjustable finger 27 for engagement with a selected surface of each of a series of depth gauging discs 54 to control the depth of successive cuts. The depth gauge assembly 53 is mounted on a key support plate 41. Arms 42 extending rearwardly from the plate carry an axle 43 on which a flanged roller is slidably and rotatably mounted. The roller rides on the vertical rear face of the upright and the flanges engage its side surfaces. Vertical travel of the roller is limited by a stop 47. The discs, corresponding in number to the number of cuts required are mounted on an axle 55 and are replaceable as a unit in a housing 57 by means of a removable shaft 58. Peripheral recesses 63 on each disc correspond to the different depths of cut to be made and each disc is rotatable to align the selected recess with the pin 27 by means of a handle 60 on a spacer 59 secured to each disc. Indicia corresponding to the depth of the recesses 63 are provided on the discs and a reference mark 64 on the housing 57. The key K is clamped to the plate 41 at 51 at a longitudinal position determined by engagement of one of a series of pivotable stops (52), Fig. 3 (not shown), with a shoulder S on the key. The plate is raised, shifted transversely relative to the roller 44 and lowered to bring the discs 54 successively into engagement with the finger 27. In another embodiment, Figs. 14 and 15, the depth gauge assembly includes means for varying the spacing between the cuts. Depth gauge bars 72 of wedge section are each slidable in an individual carrier 107 and the carriers are slidable longitudinally of a housing 109 but prevented from movement transversely of the housing by engagement of ribs 111 on the carriers with tracks 110 on the housing. Spacer discs 113 each of varying thickness splined to a rotatable shaft 112 extend partly between the carriers to determine their spacing. A coil spring 114 maintains the carriers and discs at the selected spacing. Indicia on the housing adjacent a knob 112a may be used to determine the rotation of the shaft 112 required. In a simpler form, Figs. 4 and 5 (not shown), the carriers 107 and spacers are omitted and the bars move in keyways in the depth gauge housing (70). Recesses (82) may be provided in the upper edge of the bars for engagement with a spring loaded plunger (81) mounted in the housing (70) at positions corresponding to the incremental depths of cut of a particular model of key blank. In a further form of depth gauge assembly, Fig. 6-8 (not shown), spring-mounted gauging bars (84) are located between the finger (27<SP>1</SP>) and discs (85) similar to the discs 54 of Fig. 2. To avoid the need for raising the plate 41 before shifting it transversely, sloping faces are provided on the lower ends of the bars adjacent the gauging surfaces (97) along which the tip of the finger rides. In all these embodiments the roller 44 may be replaced by a pair of rocker arms (101), Fig. 9 (not shown) pivoted to the upright 26 and to the axle 43 to give a swinging movement to the plate. Alternaivtely these embodiments may include a pawl and ratchet mechanism for automatically shifting the support plate transversely in response to vertical displacement of the plate. A ratchet bar 105 on the plate is engaged by a spring-loaded pawl 104 on the upright 26, vertical movement of the plate causing the bar and plate to shift transversely. A pivotable eccentric stop 106 limits upward travel of the plate. Two oppositely directed, selectively-operational pawls may be provided to allow for transverse movement of the plate in two opposite directions. The original key may constitute the depth gauge assembly being clamped to the plate 41 for engagement of the finger 27 successively in the teeth of the key.