GB664934A - A method of reconditioning felt printing blankets and apparatus therefor - Google Patents

Abstract

<PICT:0664934/IV (c)/1> <PICT:0664934/IV (c)/2> Felt printing blankets are reconditioned by placing them in an enclosure, supplying steam to the enclosure so as to moisten the felts, shutting off the steam supply, and causing air to flow through the enclosure to expel the remaining steam from the enclosure and to dry the felts. The apparatus used comprises an enclosure for receiving the felts, means for supplying steam to the enclosure, inlet and outlet passages for providing an air flow through the enclosure, and valves for independently controlling the steam-flow and the inlet and outlet passages for the air. The valves may be connected to an electromotor controlled by a time-adjustable clock in such manner that the opening and closing of the valves is effected automatically. As shown in Fig. 1 an enclosure 1 is provided with ledges 2 to hold the pieces of felt to be steamed and dried. If desired, the felts may be fixed in supports 21 (Fig. 3) which can be hung on the ledges 2, or they may be placed on a shelf or hung on a bar which can be supported by the ledges. A pipe 3 with valve 5 connects enclosure 1 with the steam chest of boiler 4. A pipe 6 with valve 7 and a pipe 8 with valve 9 communicate with the atmosphere. As the steam-saturated air of the enclosure and the walls thereof are hotter than the surrounding air, a strong convective air current is set up when valves 7, 9 are opened and the steam supply is cut off. The steam may thus be expelled from the enclosure and the felt may be dried. The valves may be hand-operated or may be operated automatically by a motor which may be started by a clock-mechanism 11, arranged to actuate the arm of a starting resistance 12. The clock may be set to determine the period during which steam is allowed to flow into enclosure 1. The boiler 4 may be heated by an electric heater 13, the current of which is controlled by a thermostat actuated by the boiler water and operating a regulating resistance 14. The water level in the boiler may be kept constant by a float valve 15 which conducts water from tank 16 to the boiler. Pipe 17 leads to a safety valve. A second closed chamber is provided beneath the steam chest and is connected thereto by pipe 19 and valve 20. This chamber may be used for steam-moistening the cardboard dies to be used in the printing operation.