Patent GB-587146-A (GB)
Title: A machine for fabricating strakes for boat construction or the like
IPC: B23Q27/00
Filed: 1944-11-24
Abstract: 587,146. Making parts of boats. SANDISON, A. G. S. Nov. 24, 1944, No. 23395. Convention date, Jan. 24. [Classes 83 (ii), 83 (iii) and 83 (iv)] [Also in Group XXIII] Drilling and milling machines.-A machine for making wooden or metal strakes for boat construction, such as one shaped as shown in Fig. 6 for example with convex sides and with drilled holes 92 in their edges, is constructed with a stand 1 supporting a table 4 on which the work 8 is clamped and tools such as a cutter 53 for shaping the edge of the strake and a drill 62 are mounted in a sliding saddle 11 and operate alternately. The saddle 11 is moved longitudinally by means of a rack 9 and gear 19 operated by a handle 24, and the handle 24 also operates by means of change-speed gears gears 23, 30, worm gearing 32, 33, which actuates an adjustable crank 37 which moves the cutter in a direction transverse to the motion of the saddle, 11 so as to shape the strake. The crank-pin 37 engages a groove 80, Fig. 3, in a bar 79 having a sliding engagement with a pivoted yoke 41 forming part of a link system for controlling the positions of the cutter 53. This system comprises a sliding rod 40 pivoted at 48 to a frame 42 which carries a driving motor 52 for the cutter and screw- and-nut mechanism 54, 55 for adjusting the cutter. The frame 42 is connected by a link 43 to the yoke 41 and by a slotted link 68 is optionally connected to the lower end of the yoke 41 which is provided with an extension 47 adapted to be spring pressed against an adjustable stop 75 when the link 68 is not held by its clamping-nut 72. This clamping is effected when the first half of the strake has been cut. During this operation the cutter moves outwards from the central line of the strake, and also the cutter is inclined to the vertical owing to the pivoted movement of the frame 42. The cutting of one edge is completed with the cutter 53 set at a constant angle and the extension 47 moves out of contact with the stop 75. To drill the holes 92, the cutter 53 is raised out of action and the gear 19 is disengaged from its driving shaft so as to set the saddle in the correct position to start the first drill. The saddle is held in position where the drill is to operate by means of a bolt -16 which engages gaps between bars 10 arranged adjacent to the pinion 19 and the angular position of the drill frame 59 is controlled by the link work mechanism since the frame 59 is pivoted to the frame 42. Additionally the frame 59 is controlled by the sliding movement of a bar 89 mounted in the yoke 41 which is fitted with a pin 90 bearing on the frame 59 and which is given an adjustable smaller motion than the bar 89 by means of a lever 82 having an adjustable connection with a slot in the bar 89. The drill 62 and its motor 61 are advanced to operative position by a handle 63. The curve cut by the cutter 53 is designed to conform to the equation y=A sin (Bx+C)+ Dx+E where A, B, C, D, E are arbitrary constants. The slope of the cutting-tool in a longitudinal plane is made equal to A.B cos (Bx+C). Dividing by fusion.-In place of a cutter an oxygen cutting jet may be used for treating steel bars. The strakes are used to form the bilge portion of the hull of a boat as described in Specification 586,246, [Group XXXIII].