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A vibrating float for prefinishing concrete. The float includes a float member with a planar surface, an elongated handle for manipulating the float member over the concrete with its planar surface in contact with the surface of the concrete, and a pair of pneumatically driven vibrators. The vibrato

A vibrating float for prefinishing concrete. The float includes a float member with a planar surface, an elongated handle for manipulating the float member over the concrete with its planar surface in contact with the surface of the concrete, and a pair of pneumatically driven vibrators. The vibrators are mounted on the upper surface of the float member on either side of the centrally attached handle and can be adjusted easily and quickly to vary the vibrational pattern of the float member for the most efficient and effective working of the particular concrete mix. Each vibrator has an exterior housing member with a rotatable mounted collar member within it. The collar member is cylindrical and end pieces are provided to confine a ball member within the collar member. The housing member has an air hole through it and the collar member has at least two air holes in it of different sizes. By rotating the collar member relative to the housing member, the two holes in the collar member can be selectively placed in fluid communication with the air hole of the housing member. In this manner, the volume of air passing into the interior of the collar member can be varied to propel the ball member about the central axis of the collar member at different rates to thereby create differing vibrational patterns in the float member.

대표청구항 ▼

A pneumatically driven vibrator having (i) a housing member with inner and outer surfaces extending about a first axis, said inner surface being substantially cylindrical and extending about said first axis at a first radius, said housing member having at least one hole extending therethrough from t

A pneumatically driven vibrator having (i) a housing member with inner and outer surfaces extending about a first axis, said inner surface being substantially cylindrical and extending about said first axis at a first radius, said housing member having at least one hole extending therethrough from the outer to the inner surfaces thereof, (ii) an open-ended, substantially cylindrical collar member with inner and outer surfaces extending about a second axis, said outer surface being substantially cylindrical and having a radius substantially equal to the radius of the inner cylindrical surface of said housing member and being concentrically receivable therein with said first and second axes coincident to form a common axis, said collar member having at least two holes of different sizes extending therethrough from the outer to the inner surfaces thereof, said holes being spaced from each other radially about said common axis and entering said inner surface along axes inclined to the radius of said inner surface, said collar member being rotatable about said common axis relative to said housing member at least between a first radial position with the hole in the housing member and one of the holes in said collar member in fluid communication with each other and a second radial position with the hole in the housing member and the other of the holes in said collar member in fluid communication with each other, (iii) a ball member receivable within said collar member against the inner surface thereof, (iv) means for substantially closing the open ends of said collar member to confine said ball member therein, (v) means for supplying air under a first pressure to said hole in said housing member, (vi) conduit means for placing the holes in said collar member in fluid communication with ambient air wherein air under the first pressure of said air supply flows through the interior of said collar member when said collar member is in either of said first and second positions to propel the ball member about said common axis against the inner surface of said collar member and produce vibrations, and (vii) means for selectively maintaining said collar member in said first and second positions wherein the differing air flow rates of the first and second positions due to the differently sized holes through the collar member produce at least two different vibrational patterns which can be selected as desired.