US 5,667,383 A · Disposable dental prophylaxis handpiece

Abstract

A disposable dental prophylaxis handpiece 10 is provided having a rotor 90 with vanes 92 pivotably connected thereto. The handpiece 10 includes an entrance 30 for elevated pressure fluid and an outlet 40 for discharge of the fluid after contacting the rotor 90. The elevated pressure fluid passes from the entrance 30, into a high pressure chamber 80. The high pressure chamber 80 is in contact with inlet ports 74 accessing a cylinder 72 within the handpiece 10. The cylinder 72 supports the rotor 90 with a rotational axis M of the rotor 90 off center with respect to a central axis N of the cylinder 72. The elevated pressure fluid causes the rotor 90 and an attached output shaft 97 to rotate. This in turn pauses a prophylaxis cup 160, coupled to the output shaft 97, to rotate. The rotor 90 includes a trunk 24 with a plurality of posts 93 extending therefrom and with vanes 92 connected to the posts 93 through hinges 94. The vanes 92 can pivot from a first position collapsed against the trunk 24 to a second position spaced away from the trunk 24. The vanes 92 thus can contact a cylindrical wall 78 of the cylinder 72 while the rotor 90 rotates. Exhaust ports 76 are spaced from the inlet ports 74 and provide communication with a low pressure chamber 82 which exhausts low pressure fluid to the outlet 40.

Claims20

Dependent claims

A hand held disposable dental prophylaxis handpiece driven by a source of elevated pressure, compressible fluid, comprising in combination:

an elongated plastic housing dimensioned to be supported in one's hand much like a pen;
a plastic fluid reaction device receiving the fluid as input and having a rotating shaft as an output, said fluid reaction device including a plastic rotor having a substantially rigid plastic trunk integrally formed therewith, a plurality of plastic vanes integrally formed therewith, and a means to pivotably attach said vanes to said trunk,
a hollow cavity, said cavity including means to inlet fluid into said cavity, means to exhaust fluid out of said cavity, and means to rotatably support said trunk of said rotor within said cavity wherein said pivotable attachment means includes plastic hinges each integrally formed with and interposed between each said vane and said trunk, said hinge including means to apply a force causing said vane to be urged towards and contact a periphery of said hollow cavity;
a prophylaxis cup;
coupling means from said cup to said rotating shaft such that rotation of said shaft rotates said prophylaxis cup;
said rotating shaft output coupled to said rotor such that when fluid enters said cavity, said shaft is caused to rotate, and
each said vane having an integrally formed portion which is larger away from the hinge than adjacent the hinge so as to act as a governor and a flywheel, whereby the elevated pressure compressible fluid driving said vanes can be controlled to provide substantially constant speed and high torque.

4 more elements

A disposable dental prophylaxis handpiece driven by a source of elevated pressure, compressible fluid, comprising in combination:

a housing;
a fluid reaction device receiving fluid as input and having a rotating shaft as an output, the fluid reaction device including a rotor having a substantially rigid trunk, a plurality of vanes, and a means to pivotably attach said vanes to said trunk,
a hollow cavity, said cavity including means to inlet fluid into said cavity, means to exhaust fluid out of said cavity, and means to rotatably support said trunk of said rotor within said cavity;
a prophylaxis cup;
coupling means from said cup to said rotating shaft such that rotation of said shaft rotates said prophylaxis cup;
said rotating shaft output coupled to said rotor such that when fluid enters said cavity, said shaft is caused to rotate;
wherein said means to rotatably support said rotor within said cavity includes a means to support said rotor with a rotational axis of said rotor spaced from a central axis of said hollow cavity;
wherein a seal point is provided between said rotor and said cavity, said seal point located between said inlet means and said exhaust means, said seal point defined by at least one portion of said rotor contacting said cavity between said inlet means and said exhaust means;
whereby fluid passing through said inlet means and into said cavity is prevented from accessing said exhaust means by passing around a side of said rotor closest to said seal point;
wherein said rotor includes a recess adjacent each vane, each said recess having a contour which can receive an adjacent said vane therein when said vane is pivoted about said pivotable attachment means;
and
wherein said pivotable attachment means includes a hinge interposed between at least one of said vanes and said trunk, said hinge including means to apply a force causing extension of said vane out of an adjacent said recess, each said vane having a cross-sectional area which is larger away from said hinge than near said hinge.

9 more elements

A method for utilizing high pressure compressible fluid to cause a dental prophylaxis device to rotate, including the steps of:

forming a rotor to include a trunk and a plurality of vanes;
connecting each vane through a hinge to the trunk, the hinge allowing each said vane to pivot with respect to the trunk between a first collapsed position and a second extended position;
forming each vane with a mass center spaced from its hinge connection providing both a governor and flywheel effect extracting from the high pressure fluid high torque at low speed;
orienting the rotor within a hollow cavity;
providing an inlet fluid port passing into the cavity;
providing an outlet fluid port passing into the cavity;
coupling the rotor to a means to transmit rotational energy from the rotor to the dental prophylaxis device;
coupling the inlet fluid port to a source of fluid;
and
directing fluid from the source of fluid through the inlet fluid port and into contact with the vanes of the rotor, causing the rotor and the dental prophylaxis device to rotate;
including the further step of forcing the vanes toward the second position about the hinge such that the vanes are biased away from the trunk unless a greater force is applied against the vanes, causing the vanes to pivot toward the first position adjacent the trunk.

8 more elements

A dental prophylaxis handpiece, comprising in combination:

a fluid reaction device having a substantially constant velocity rotational output for imparting rotation;
a prophylaxis cup;
said fluid reaction device including a rotor having a trunk, vanes and hinge means between said trunk and said vanes to pivot said vanes between a first position and a second position;
a wall surrounding said rotor;
said first position defined by said vanes collapsed adjacent said trunk with a portion of said vanes abutting said wall;
said second position defined by said vanes pivoted away from said trunk with a portion of said vanes abutting said wall;
said hinge means including a biasing means to apply a force causing extension of said vanes adjacent said wall;
said rotor trunk, hinge and vanes formed from plastic, said vanes having a mass which increases as it extends from said hinge;
an inlet passing through said wall coupled to a source of fluid;
an outlet passing through said wall;
and
an output means interposed between said rotor and said prophylaxis cup.

9 more elements

Dependencies are inferred from the claim text.

Disposable dental prophylaxis handpiece

Life of this patent

Disposable dental prophylaxis handpiece

Life of this patent

Abstract

Claims20