Patent GB-491429-A (GB)
Title: Improvements in and relating to electric ironers
IPC: B21D39/04
Filed: 1938-02-18
Abstract: 491,429. Ironing-machines. BRITISH THOMSON-HOUSTON CO., Ltd. Feb. 18, 1938, No. 5217. Convention date, Feb. 18, 1937. [Class 138 (ii)] In an ironing-machine having a roller coacting with a concave shoe, with power means for rotating the roller and for swinging the shoe into and out of contact with the roller, and additional means for releasing the pressure between the roller and shoe in certain circumstances, there is provided a single lever 105 which is movable in two directions and may alternatively control the power means or the additional means according to its directions of movement. The lever 105 is secured to a shaft 106, Fig. 18, which is slidably and rotatably mounted in the machine frame. When the lever 105 is operated, as by the knee of the operator, to cause the shaft to slide, it controls the shoe movements and the rotation of the roller, whilst when the lever 105 is rotated in a vertical plane to rotate the shaft 106 it affords an additional means for releasing the shoe for example in the case of failure of the power supply. The shoe 1, Fig. 5, is pivotally connected to a shaft 12 by arms 10, and an arm 64 is normally latched to the shaft by a pawl 65 pivoted on the arm and normally urged by a spring 69 into engagement with a slot 67 in a collar 68 keyed to the shaft. An adjustable spring 74 urges the shoe into contact with the roller 2 as shown, but when an eccentric 61 is rotated through 180‹ from the position shown the shoe is moved away from the roller, being returned by the spring 74 on a further 180‹ rotation of the eccentric. The eccentric rotates on a fixed tubular member 27 and the strap surrounding the eccentric is universally jointed to the arm 64. A worm wheel 44, Fig. 2, constantly driven by a motor 31 is rotatably mounted on a shaft 30 to which the roller 1 is secured by discs 16, 17. A pinion 48 is rigid with the worm wheel, and the hub 50 of an internal gear wheel 51, Fig. 18, is rotatable on a bearing surface between the worm wheel 44 and pinion 48. The internal gear wheel meshes with pinions 52 rotatable on stub shafts 53 fixed to an arm 54 which is secured to the shaft 30. Pinions 52 also mesh with the pinion 48. When the internal gear wheel is free to rotate the shaft 30 remains stationary due to inertia or friction, but when it is held the drive of the worm wheel 44 is transmitted to the shaft 30 through the epicyclic train. The internal gear wheel is held stationary by the engagement of an arm 58 in a notch 59, Fig. 17, in the gear wheel, the arm 58 being carried by a sleeve 55 having another arm 98 riding on a cam 97 secured to the eccentric 61. A circular flange 80, Fig. 18, integral with the eccentric is provided with a radial slot in which a key 81 is slidably carried, the key being urged outwardly by a spring 82, Fig. 2, but being held by one end of a C-shaped trip lever 86, Fig. 18, slidably mounted on pins 87 having springs 89 between the lever and the heads of the pins. When the shaft 106 is caused to slide to the right it rotates a shaft 91 clockwise through an arm 109, and, through an arm 90, moves the trip lever 86 so that key 81 moves outward to engage one of a number of notches 92 in a flange 93, integral with the continuously rotating worm wheel 44 ; i.e. the eccentric 61 and worm wheel now rotate together, but, on the release of the knee pad 105, the trip lever 86 is returned to its normal position by its springs so that as the eccentric completes 180‹ rotation the other end of the trip lever 86 engages and withdraws the key 81 to break the connection between the worm wheel and the eccentric 61 which now stops with the shoe contacting with the roller, the rotation of which has been started and continues by the engagement of the arm 58 in the recess of the internal gear wheel 51. The shape of the cam 97 is such that the drive to the roller is started before full ironing pressure is attained between the roller and shoe. The eccentric is rotated by a further 180‹ to move the shoe out of contact with the roller and to disconnect the drive to the roller by a second movement of the knee pad 105 to the right. On moving the lever 105 downwards, Fig. 5, a rod 111 is raised against the action of a spring 112 and lifts the pawl 65 out of engagement with the sleeve 68 thereby unlocking the shoe from the force of the spring so that the shoe moves away from the roller under its resilience. For keeping the roller stationary with the shoe in contact therewith a shaft 103, Fig. 18, having a cam lever 104 thereon and an operating handle, not shown, on the exterior of the gear casing, is provided. On rotating the shaft 105 clockwise through 90‹ from the position shown, the cam 104 engages and raises the arm 98 thereby withdrawing arm 58 from the notch 59 in the internal gear wheel 51 to stop the drive to the roller. On a slight further clockwise movement of the shaft 103 the cam 104 engages and moves the C-lever 86 to reconnect the eccentric 61 to the worm wheel and move the shoe. The same effect may be produced by rotating the shaft 103 counterclockwise from the position shown through slightly more than 90‹. These two last functions of the shaft 103 provide an alternative to the sliding movement of the lever 105 for controlling shoe movement and roller rotation. In a modification, Fig. 19, the eccentric 61 is replaced by a gear wheel 117 loose on the tubular member 27 and integral with a casting including the cam 97, flange 80 and driving key 81. The gear 117 drives a gear 118 loose on a stub shaft 119 and carrying a cam 120 which coacts with a spring-pressed lever 121 on the shoeactuating shaft 12. The cam 120 is provided with flats 125, 126 which prevent over travel of the cam beyond the two stages of 180‹ each.