GB883434A - Mixing machines - Google Patents

Abstract

883,434. Batch mixing machines. TRIANCO Ltd. Feb. 21, 1958 [Feb. 25, 1957], No. 6297/57. Class 86. [Also in Group XXXVII] A machine for mixing batches of concrete comprises a mixer 1 Fig. 1, having contrarotating paddles 4 in a drum 5, an elevator 30 for mixing dry materials and depositing them into the mixer, a water sprinkler 39 operable by an electrically controlled meter 40, for adding water to the materials in the mixer a valve 7 in the bottom of the drum 5 for discharging the mixed concrete and a timer unit 42, Fig. 3 which controls the operation of the elevator 30, the sprinkler 39 and the valve 7 in a predetermined time cycle infinitely variable between upper and lower limits. The driving shafts 3 for the paddles 4 are sealed where they pass through the drum 18 in the manner described with reference to Fig. 2 (not shown) and are driven from an electric motor 27. The valve 7 is arcuate and pivoted on a shaft 8 rotatable by a electric motor driven reduction gear 12 through a crank 11 and connecting rod 10 under the control of a counterbalance spring 13 and chain 14 co-operating with the arcuate surface 15 of the valve 7. The elevator comprises a bucket slidable up and down rails 32 by means of an electric motor 33, and electrical operated brake 36. The motor 33 is reversible and controlled by upper and lower limit switches 37, 38. The bucket is tippable for unloading its charge, by a cam surface 34 thereon engaging fixed abutments 35 at the top of the rails 32. The water supply is effected by a centrifugal pump 41. Referring to Fig. 3, the timer unit 42 mounted on the machine frame 2 comprises a motor driven shaft 43, the speed being infinitely variable between upper and lower limits and cams 44 to 49 angularly adjustable relative to the shaft. The cams operate rocker arm 56 which in turn operate switches 50 to 55 which respectively control the motor for the valve 7; a signal light prior to the elevation of the bracket 31; the elevator motor in the "raise" direction; the elevator motor in the "lower" direction; an electrical interlock system described with reference to Fig. 5 (not shown) which prevents stopping of the machine at an undesired point of its cycle and loading of mixer when the valve 7 is open; and lastly the water meter. The various parts of the cycle may be altered by adjustment of the cams relative to the shaft 43. The end switches 50, 55 are carried on adjustable plates 61, 62 to. vary the times of the water injection and opening of the discharge valve 7.