GB738242A - Frequency controlled vibratory mechanism - Google Patents

Abstract

738,242. Testing materials by the use of vibrations. AVERY, Ltd., W. & T. (Schenck Maschinenenfabrik Ges., C.). Sept. 26, 1953, No. 26530/53. Class 106 (2). [Also in Group XXIV] In a machine wherein a test-piece 1 is held between a chuck 3 on a fixed ring dynamometer 10 and a chuck 2 which is oscillated horizontally by a rotary vibrator 6, the vibratory assembly is mounted on links 5 and comprises a squirrel-cage motor 23 driving adjustable or interchangeable eccentric masses, the motor being supplied with alternating current whose frequency is varied to vary the frequency and consequently the amplitude of the oscillations. The motor 23 is supplied by an external generator 22 driven by a motor 13 through continuously-variable change-speed chain gearing 16. A fly-wheel 15 on the motor 13 obviates sudden variations in the speed of rotation following changes of gear ratio or following any variations in the mains supply. The ratio of the gearing 16 is varied by a motor 17 which is controlled by apparatus 24, this apparatus comprising adjustment knobs for selection of definite speeds or amplitudes of oscillation, and a relay which is actuated by a stroke feeler 11 on the dynamometer 10 to maintain a constant amplitude. Alternatively the feeler 11 may be mounted between the vibratory assembly and its foundation. It is stated that use of the gearing may be avoided by employing a variable-speed motor, and that the vibratory mechanism is applicable to inertia conveyers, sieves, oscillating tables and bunker discharge conveyers.