Screening machine

Claim 2

A screening machine consisting of a frame, a flexible screen floor a plurality of parallel screen floor supports, means attaching said screen floor to said screen floor supports, mounting means mounting said screen floor supports on said frame so that said screen floor supports are rockable about fixed axes relative to said frame, and driving means for oscillating said screen supports about said fixed axes in such a way that adjacent screen floor supports alternately approach and recede from each other in order to flex and stretch alternately the screen floor between, thus setting up a stationary wave in said screen floor, said mounting means comprising a plurality of supporting tubes, means fixing said screen floor supports to said supporting tubes, and means rotatably mounting said supporting tubes in said frame, and said driving means including two reciprocable longitudinal beams, a plurality of rocking levers which are fitted at one of their ends alternately to opposite ends of alternate supporting tubes, means pivotally connecting said rocking levers at their other ends alternately to said longitudinal beams, and means for oppositely reciprocating said longitudinal beams to oscillate said screen floor supports.

Claim 3

A screening machine as set forth in claim 1, wherein said longitudinal beams are located one on each side of said frame, and said means for oppositely reciprocating said longitudinal beams includes a motor, and a pair of connecting rods and eccentrics which are 180* out of phase with each other.

Claim 4

A screening machine as set forth in claim 2, wherein said frame is supported on springs, and said frame has an extension at the feed end of the machine, said driving motor being mounted on said extension.

Claim 5

A screening machine as set forth in claim 1, including flexible plates at the feed and delivery ends of said screening floor, transverse members extending between the sides of said frame at the feed and delivery ends, and means attaching said flexible plates to said transverse members and to one of said screen floor and said screen floor supports.

Claim 6

A screening machine as set forth in claim 1, including flexible plates at the sides of said screening floor, and means attaching said flexible plates to the sides of said frame and to one of said screen floor and said screen floor supports.

Claim 7

A screening machine as set forth in claim 1, wherein said means rotatably mounting said supporting tubes in said frame consists of one of the group comprising roller bearings, elastic bearing bushes and plain bearings made of, for example, either one of synthetic plastics and bronze having a low coefficient of friction of self-lubricating properties.

Claim 8

A screening machine as set forth in claim 1, including a second screening floor, said first and said second floor being arranged one above the other, a second set of floor supports, means attaching said second floor to said second set of floor supports, and means for driving said second set of floor supports so as to flex and stretch said second floor in the same way as said first floor.

Claim 9

A screening machine as set forth in claim 7, wherein said means for driving said second floor supports includes support members which mount said second floor supports on said first floor supports.

Claim 10

A screening machine as set forth in claim 7 wherein said means for driving said second floor supports includes support members which mount said second floor supports on said first supporting tubes.

Claim 11

A screening machine as set forth in claim 1 wherein each of said screen floor supports is a strip which extends all the way across said screen floor.

Claim 12

A screening machine as set forth in claim 1, wherein each of said screen supports consist of a plurality of individual members to which said screen floor is attached at separate points.

Claim 13

A screening machine as set forth in claim 1 including a second floor formed of impermeable nonscreening material, said first and said second floor being arranged one above the other, a second set of floor supports, means attaching said second floor to said second set of floor supports, and means for driving said second set of floor supports so as to flex and stretch said second floor in the same way as said first floor.

Claim 14

A screening machine consisting of a frame, a flexible screen floor, a plurality of parallel screen floor supports, means attaching said screen floor to said screen floor supports, mounting means mounting said screen floor supports on said frame so that said screen floor supports are rockable about fixed axes relative to said frame, and driving means for oscillating said screen supports about said fixed axes in such a way that adjacent screen floor supports alternately approach and recede from each other in order to flex and stretch alternately the screen floor between, thus setting up a stationary wave in said screen floor, and including a second screen floor, said first and said second floor being arranged one above the other, a second set of floor supports, means attaching said second floor to said second set of floor supports, and means for driving said second set of floor supports so as to flex and stretch said second floor in the same way as said first floor, said means for driving said second set of floor supports including second supporting tubes, means fixing said second floor supports on said second supporting tubes, means rotatably mounting said second supporting tubes in said frame, second rocking levers alternately fitted at one of their ends to opposite ends of alternate supporting tubes, and means pivotally connecting the other ends of said rocking levers alternately to said reciprocable longitudinal beams which drive said first floor.

Claim 15

A screening machine consisting of a frame, a flexible screen floor, a plurality of parallel screen floor supports, means attaching said screen floor to said screen floor supports, mounting means mounting said screen floor supports on said frame so that said screen floor supports are rockable about fixed axes relative to said frame, and driving means for oscillating said screen supports about said fixed axes in such a way that adjacent screen floor supports alternately approach and recede from each other in order to flex and stretch alternately the screen floor between, thus setting up a stationary wave in said screen floor, and including a second screen floor, said first and said second floor being arranged one above the other, a second set of floor supports, means attaching said second floor to said second set of floor supports, and means for driving said second set of floor supports so as to flex and stretch said second floor in the same way as said first floor, said means for driving said second set of floor supports including second supporting tubes, means fixing said second floor supports on said second supporting tubes, means rotatably mounting said second supporting tubes in said frame, second rocking levers alternately fitted at one of their ends to opposite ends of alternate supporting tubes, and means pivotally connecting the other ends of said rocking levers alternately to said reciprocable longitudinal beams which drive said first floor.

Claim 16

A screening machine consisting of a frame, a flexible screen floor, a plurality of parallel screen floor supports, means attaching said screen floor to said screen floor supports, mounting means mounting said screen floor supports on said frame so that said screen floor supports are rockable about fixed axes relative to said frame, driving means for oscillating said screen supports about said fixed axes in such a way that adjacent screen floor supports alternately approach and recede from each other in order to flex and stretch alternately the screen floor between, thus setting up a stationary wave in said screen floor, a second floor formed of impermeable nonscreening material, said first and said second floor being arranged one above the other, a second set of floor supports, means attaching said second floor to said second set of floor supports, means for driving said second set of floor supports so as to flex and stretch said second floor in the same way as said first floor, said means for driving said second set of floor supports including second supporting tubes, means fixing said second floor supports on said second supporting tubes, means rotatably mounting said second supporting tubes in said frame, second rocking levers alternately fitted at one of their ends to opposite ends of alternate supporting tubes, and means pivotally connecting the other ends of said rocking levers alternately to said reciprocable longitudinal beams which drive said first floor.

Claim 17

A screening machine consisting of a frame, a flexible screen floor, a plurality of parallel screen floor supports, means attaching said screen floor to said screen floor supports, mounting means mounting said screen floor supports on said frame so that said screen floor supports are rockable about fixed axes relative to said frame, driving means for oscillating said screen supports about said fixed axes in such a way that adjacent screen floor supports alternately approach and recede from each other in order to flex and stretch alternately the screen floor between, thus setting up a stationary wave in said screen floor, a second floor formed of impermeable nonscreening material, said first and said second floor being arranged one above the other, a second set of floor supports, means attaching said second floor to said second set of floor supports, means for driving said second set of floor supports so as to flex and stretch said second floor in the same way as said first floor, said means for driving said second set of floor supports including second supporting tubes, means fixing said second floor supports on said second supporting tubes, means rotatably mounting said second supporting tubes in said frame, second rocking levers alternately fitted at one of their ends to opposite ends of alternate supporting tubes, and means pivotally connecting the other ends of said rocking levers alternately to said reciprocable longitudinal beams which drive said first floor.