Klassiervorrichtung mit Rüttelsieb

1356764 Screening apparatus ISRAEL AGRICULTURE MINISTRY OF 19 April 1972 [20 May 1971] 18122/72 Heading B2H An oscillating screen 1 rests on vertically displaceable spring means 2 biasing the screen into an uppermost position, and is provided with means for pulling it downwards against the action of said spring means 2, means for periodically releasing said pulling means, and stop. means to arrest the upward movement of the screen. The screen is supported by leaf springs 2 mounted at the top of arms 3 keyed on axles 4, and is oscillated via a rod 6 which is pivotally connected to the screen and cooperates with an eccentric wheel 7 driven by a motor 11. A rod 14 is connected at one end to the screen and at its other end to an arm 12 pivotally mounted in a pair of lugs 13. The other end of the arm 12 is provided with a roller 16 which cooperates with a cam 17 having a cut out portion and keyed on an axle 18. The shape of the cam 17 is such that, during rotation thereof, it causes the arm 12 and this screen 1 to move downwards until the roller 16 faces the cut out portion of the cam. At this point the arm 12 is released from the downward force exerted by the cam 17 and the screen moves rapidly upwards under the influence of the springs 2 until the arm 12 contacts a stop member 15. The abrupt termination of the upward movement causes any particles which were stuck in the apertures of the screen to be ejected therefrom.