Patent GB-107614-A (GB)
Title: Improvements in or relating to Machines for Levelling the Bottoms of Boots or Shoes.
IPC: A43D35/00
Filed: 1916-06-02
Abstract: 107,614. Jerram, A. E., Gouldbourn, J., and British United Shoe Machinery Co. June 2, 1916. Sole,- levelling.- Sole - levelling machines of the type described in Specification 14,567/10 are provided with automatically adjusted means to compensate for variations in the thickness of the bottoms of different boots, with improved forms of locking or supporting devices for the work-measuring mechanism, and with mechanism for producing the relative rolling and tipping of the work and form which is in operation while the work and form are being brought together and with which the member to be rolled or tipped enters into engagement to receive movement therefrom when the relative operative position of the work and form is attained. The machine is of the duplex character, as in the machine described in the Specification above referred to; the jacks being swung alternately from a vertical into an inclined position in line with the corresponding form and then rolled or tipped in contact with the form upon two links 2, 3, Fig. 1, pivoted respectively at 4, 37 to the jack and to separated points on the machine frame. In the present machine, movement for initiating levelling pressure is imparted to the form 1 instead of to the jack, for which purpose the lever 5 which adjustably carries the forms and is pivoted at 5* on the machine frame towards one end of the forms in order to exert different pressures on different parts of the work, as described in Specification 12,666/11, is connected to a bell-crank arm 6 mounted on the pivot 5* and engaging the middle of a shaft 7, the ends of which pass into side walls of the lever 5. Bolts 8 pinned to the shaft 7 carry heavy springs 11 between adjustable collars 9 and sliding collars 12 bearing on the lever 5, there being adequate clearance between the ends of the shaft and the openings in the lever so that the shaft may be moved laterally relatively to the lever by the arm 6 when the lever is arrested by the work and so that the springs 11 may be compressed to apply the levelling pressure. The arm 6 is actuated through a toggle 13, 14 and rod 15, Figs. 1 and 3, from a crank 16 on a shaft 17, which carries a gear 18 meshing with a gear 19 of twice the diameter on a shaft 20. This shaft carries cam disks 21 for controlling the jacks, the groove 22 in each disk being engaged by a roll 23 mounted on an arm of a bell-crank 24, which is connected by a link 25 to a second bell-crank 26 pivoted to the machine frame and carrying a pin 27 engaging a cam slot 28 on one end of the link 3. This link is provided with a curved jaw 35 concentric with the pivot 37 and adapted to engage a stud 36 on the machine frame, the surface 38 of the jaw being extended in the manner and for the same purpose as the clip link described in Specification 14,567/10. As the roll 23, in the rotation of the disk 21, passes out of a concentric and into an eccentric portion of the cam groove 22, the pin 27 is lowered in the slot 28 and allows the jack under its own weight to swing about the pivot 4 carrying the link 3 with it; when the surface 38 contacts with the stud 36, the link 3 is swung about the pivot 37 to cause the jaw 35 to be advanced over the stud. The roll 23 then engages another concentric portion of the cam groove 22, and later, another concentric portion, when the reverse order of operations takes place. The shaft 20 loosely carries a sleeve which is driven by worm gearing 44 from the main shaft 45 and bears an eccentricwhich is encircled by a strap on a rod 39 pivoted to one arm of a lever 40; the other arm of this lever, which is continuously reciprocated, is divided into two portions 42, each of which is formed with a deep recess 43 adapted to be engaged by the pivot 37 of the corresponding jack as the latter swings into operative position. When this engagement is effected, the links 2, 3 are swung so as to give the jack a rolling and tipping motion on the links 2, 3 similar to that of the jacks in the machine described in Specification 14,567/10. The main shaft 45 carries a second gear 46 meshing with a wheel 47, Fig. 3, loose on the shaft 17; the wheel 47 is arranged to make one revolution for every three of the eccentric, and is controlled by a one-revolution clutch so as to move the shaft 17 in timed relationship with the eccentric. This clutch comprises a rod 48 mounted in a bore in the crank 16 and normally urged by a spring 51 in a direction to force its head 49 into engagement with one or other of three recesses 50 in the wheel 47. The rod is formed with a transverse notch 53 which is normally engaged by a curved block 54 on a treadleoperated rod 55. When the treadle is depressed and released again, the rod 48 is released and its head is forced into engagement with the wheel 47, which then drives the shaft 17; as the crank 16 completes one revolution a wedge-shaped end portion of the block 54 engages an inclined wall in the notch 53 and the rod 8 is disengaged from the wheel 47. Each jack comprises a support 29, Figs. 4 and 5, for an iron last 30 provided with a cylindrical shank 31 adjustable in a carrier 32, which is pivoted at 4, Fig. 1, to the link 2; an adjusting screw 33 passes through this link and is maintained in contact with the machine frame bv the weight of the jack. The support 29, Figs. 4 and 5, is upwardly pressed by two springs 60, 61 to an amount limited by a bolt 58<1> which passes loosely through a flange 59 on the carrier and adjustably engages a hole in a flange 57<1> on the support. The shank 31 is slotted at 56 and the lower walls 57, 58 of the slot are inclined outwards at equal angles to coact with inclined faces 64 on wedges 62, 63 mounted to slide towards and from one another upon fixed supports 66. The wedges 62, 63 are formed also with other but differently inclined faces 65 in engagement with a longitudinally-movable wedge 67, which is pivoted on a link 68 connected to the inner end of a lever 69 fulcrumed near its outer end on a rod 70 pivoted to the flange 57<1>. A spring-pressed plunger 71 bears on the outer end of the lever 69 and normally acts to thrust the wedge 67 upwards. The angle of the wedge 67 is somewhat less than twice the angle whose tangent is equal to the coefficient of friction between the surface of the wedge 67 and the surface 65, while the angle between the inclined walls 57, 58 is considerably greater; as a consequence, a slight movement of the shank 31 necessitates a proportionately greater movement of the wedge 67 to prevent the wedges 67, 62, 63 from binding, and ior this purpose the fulcrum of the lever 69 is located near its outer end. In the operation of the machine, as the jack in operative position commences its rolling and tipping movement, one of a pair of cam pieces 72, Fig. 1, on' the edge of the cam disk 21 engages a bell-crank 73 and swings it so that one of two faces on its other arm forms an abutment for the end of the lever 69. If, therefore, the last support is depressed by the form as a result of any increase in the thickness of the shoe bottom, the rod 70 will cause the lever 69 to swing about this abutment and withdraw the wedge 67 sufficiently to prevent it from binding between the wedges 62, 63. As the cam piece 72 passes from beneath the lever 73, the spring plunger 71 swings the lever 69 to raise the wedge 67 between the wedges 62, 63, and so to lock the last support against levelling pressure. The wedge locking or supporting device may be varied, for instance, by employing only a single wedge which bears on one face of a supporting wedge, the other face of which bears on an abutment of smooth surface on which the wedge is free to slide in the line of movement of, and of the thrust in, the member to be supported. Specification 107,728 also is referred to.