Hydraulic chuck

{
  "publication_number": "US3814448A",
  "country": "US",
  "kind": "A",
  "title": "Hydraulic chuck",
  "abstract": "A chuck construction comprising a chuck body having a plurality of substantially radially movable jaw carriers slidably mounted thereon. At least one jaw carrier is drivingly connected to a driven piston which is slidably mounted on the chuck body. In one embodiment a driving piston is slidably mounted relative to the chuck body and, in association with the chuck body, defines a fluid pressure system which actuates the driven piston whereby movement of the driving piston, acting through an intermediate pressurized fluid, causes movement of the driven piston and its associated jaw carrier. The driving piston is connected to an actuating mechanism, such as a conventional draw bar. In one embodiment, all of the jaw carriers are connected to separate driven pistons which are operatively related to the fluid pressure system so that the driven pistons and their respective jaw carriers are individually slidably moved when the driving piston is moved. This chuck construction permits relative radial movement of the jaw carriers to compensate for workpiece eccentricity. In a further embodiment, the jaw carriers are mechanically interconnected to each other for simultaneous radial movement therewith and with this arrangement one or more jaw carriers as desired may be connected to a driven piston.",
  "claims": [
    "1. In a chuck construction having a chuck body and a plurality of jaw carriers slidably mounted on said chuck body and movable relative thereto toward and away from a workpiece engaging position, said jaw carriers each having at least a radial component of motion relative to the longitudinal axis of said chuck construction, and actuator means for causing movement of said jaw carriers relative to said chuck body, the improvement wherein said actuator means comprises: a source of fluid under pressure; said chuck body including wall means defining a substantially closed chamber adapted to have said pressure fluid received therein; piston means slidably disposed in said chamber and coacting with at least one of said jaw carriers for moving same relative to said chuck body; means providing fluid communication between said source and said chamber, whereby transfer of fluid from said source to said chamber causes movement of said piston means, which movement of said piston means in turn causes a corresponding movement of said one jaw carrier; and mechanical means drivingly interconnecting said jaw carriers for causing all of said jaw carriers to be simultaneously moved through substantially equal distances in response to movement of said piston means; said mechanical means including a gear member concentric with and rotatably supported on said chuck body, said piston means having a gear rack portion provided thereon and disposed in meshing engagement with said gear member, and each of said jaw carriers having a gear rack portion associated therewith and disposed in meshing engagement with said gear member.",
    "2. In a chuck construction having a chuck body and a plurality of jaw carriers slidably mounted on said chuck body and movable relative thereto toward and away from a workpiece engaging position, said jaw carriers each having at least a radial component of motion relative to the longitudinal axis of said chuck construction, and actuator means for causing movement of said jaw carriers relative to said chuck body, the improvement wherein said actuator means comprises: first wall means defining a substantially closed primary chamber adapted to have a substantially incompressible pressure fluid disposed therein, said primary chamber being substantially coaxially aligned with the longitudinal axis of said chuck body and disposed internally thereof; primary piston means slidably disposed in said primary chamber for effecting pressurization of said pressure fluid; second wall means defining a substantially closed secondary chamber adapted to have said substantially incompressible pressure fluid disposed therein; second piston means slidably disposed in said secondary chamber and coacting with at least one of said jaw carriers for moving same relative to said chuck body; and passageway means providing fluid communication between said primary and secondary chambers, whereby movement of said primary piston means in one direction within said primary chamber causes pressurization and transfer of fluid from said primary to said secondary chamber for causing movement of said second piston means, which movement of said second piston means in turn causes a corresponding movement of said at least one jaw carrier; said primary piston means comprising a sleevelike member coaxially aligned with And slidably supported on said chuck body, said chuck body and said sleevelike member coacting to define said primary chamber therebetween with said primary chamber having a substantially annular configuration, and said sleevelike member having a substantially radially extending flangelike piston portion disposed within said primary chamber and positioned in slidable and sealing engagement with said chuck body.",
    "3. A chuck construction according to claim 2, wherein said primary piston means sealingly divides said primary chamber into first and second compartments disposed on opposite sides of said primary piston means; wherein said secondary piston means divides said secondary chamber into third and fourth compartments disposed on opposite sides of said secondary piston means; and wherein said passageway means includes a first flow passage providing communication between said first and third compartments and a second flow passage providing communication between said second and fourth compartments; whereby movement of said primary piston means in said first direction causes pressure fluid to be transferred from said first compartment to said third compartment for causing movement of said secondary piston means in one direction so that said one jaw carrier is moved toward said work engaging position, and whereby movement of said primary piston means in the opposite direction causes pressure fluid to be transferred from said second compartment to said fourth compartment for causing movement of the secondary piston means in the other direction so that said one jaw carrier is moved away from said position.",
    "4. A chuck construction according to claim 2, wherein said first and second wall means each comprise a portion of said chuck body and define said primary and secondary chambers internally of said chuck body.",
    "5. A chuck construction according to claim 2, wherein said secondary chamber is formed in said chuck body and is spaced radially outwardly from the longitudinal axis of said chuck construction, and wedge means coacting between said one jaw carrier and said secondary piston means for causing movement of said one jaw carrier in response to displacement of said secondary piston means within said secondary chamber.",
    "6. A chuck construction according to claim 5, wherein the longitudinally extending direction of said secondary chamber lies within a plane which is substantially perpendicular to the longitudinal axis of said chuck construction, the longitudinal direction of said secondary chamber also being substantially transverse to the direction of movement of said one jaw carrier; said piston portion of said primary piston means dividing said primary chamber into first and second compartments which are sealingly isolated from one another on opposite sides of said primary piston means, and said secondary piston means dividing said secondary chamber into third and fourth compartments which are sealingly isolated from one another on opposite sides of said piston portion; and said passageway means including a first flow passage providing fluid communication between said first and third compartments, and a second flow passage providing fluid communication between second and fourth compartments, whereby reciprocation of said primary piston means causes a corresponding reciprocation of said secondary piston means.",
    "7. A chuck construction according to claim 2, further including mechanical means drivingly interconnecting said jaw carriers for causing all of said jaw carriers to be simultaneously moved through substantially equal distances in response to movement of said secondary piston means.",
    "8. In a chuck construction having a chuck body and a plurality of jaw carriers slidably mounted on said chuck body and movable relative thereto toward and away from a workpiece engaging position, said jaw carriers each having at least a radial component of motion relative to the longitudinal axis of said chuck construction, and actuator means for causing moVement of said jaw carriers relative to said chuck body, the improvement wherein said actuator means comprises: first wall means defining a substantially closed primary chamber adapted to have a substantially incompressible pressure fluid disposed therein; primary piston means slidably disposed in said primary chamber for effecting pressurization of said pressure fluid; second wall means defining a substantially closed secondary chamber adapted to have said substantially incompressible pressure fluid disposed therein; second piston means slidably disposed in said secondary chamber and coacting with at least one of said jaw carriers for moving same relative to said chuck body; cooperating self-locking wedge means coacting between said secondary piston means and said one jaw carrier for effecting movement of said one jaw carrier in response to movement of said secondary piston means while preventing movement of said one jaw carrier due to application of externally applied forces thereto; and passageway means providing fluid communication between said primary and secondary chambers, whereby movement of said primary piston means in one direction within said primary chamber causes pressurization and transfer of fluid from said primary to said secondary chamber for causing movement of said second piston means, which movement of said second piston means in turn causes a corresponding movement of said at least one jaw carrier.",
    "9. A chuck construction according to claim 8, wherein further secondary piston means are respectively associated with each of the remaining jaw carriers, each of the further secondary piston means being slidably disposed within a respective secondary chamber, and said passageway means providing fluid communication between each of said further secondary chambers and said primary chamber, whereby pressurization of the fluid within said primary chamber due to displacement of said primary piston means causes pressure fluid to be transferred to each of said secondary chambers for causing movement of each of said secondary piston means, whereby all of said jaw carriers are movable relative to said chuck body.",
    "10. In a chuck construction having a chuck body and a plurality of jaw carriers slidably mounted on the chuck body and movable relative thereto toward and away from a workpiece engaging position, each jaw carrier having at least a radial component of motion relative to the longitudinal axis of said chuck construction, the improvement comprising: compensating actuator means drivingly connected to said plurality of jaw carriers for permitting simultaneous movement of same toward said operative position and for permitting said plurality of jaw carriers to apply substantially equal gripping forces to said workpiece while permitting said individual jaw carriers to be moved through different distances to compensate for workpiece eccentricity said compensating actuator means including a closed fluid pressure system adapted to contain therein a predetermined quantity of a substantially incompressible pressure fluid; said system including a primary fluid chamber adapted to contain therein said pressure fluid and first piston means slidably disposed within said primary chamber for causing pressurization of the fluid therein to cause movement of said jaw carriers toward said workpiece engaging position; said system including a plurality of secondary chambers each being associated with one of said jaw carriers, each of said secondary chambers having secondary piston means slidably disposed therein and coacting with a respective jaw carrier for causing corresponding movement thereof when said secondary piston means is slidably moved within its respective secondary chamber; self-locking wedge means coacting between each secondary piston means and its respective jaw carrier for causing each said jaw carrier to be linearly displaced in response to movement of its respective secondary piston means while preventing movement of said Jaw carrier in response to externally applied forces; and said system further including passageway means providing fluid communication between each of said secondary chambers and said primary chamber for causing movement of said secondary pistons and said jaw carriers in response to displacement of said first piston means.",
    "11. In a chuck construction having a chuck body and a plurality of jaw carriers slidably mounted on the chuck body and movable relative thereto toward and away from a workpiece engaging position, each jaw carrier having at least a radial component of motion relative to the longitudinal axis of said chuck construction, the improvement comprising: compensating actuator means drivingly connected to said plurality of jaw carriers for permitting simultaneous movement of same toward said operative position and for permitting said plurality of jaw carriers to apply substantially equal gripping forces to said workpiece while permitting said individual jaw carriers to be moved through different distances to compensate for workpiece eccentricity; said compensating actuator means including a closed fluid pressure system adapted to contain therein a predetermined quantity of a substantially incompressible pressure fluid; said system including a primary fluid chamber disposed internally of the chuck body and adapted to contain therein said pressure fluid, said primary chamber being substantially concentric with the longitudinal axis of said chuck body, and first piston means slidably disposed within said chamber for causing pressurization of the fluid therein to cause movement of said jaw carriers toward said workpiece engaging position; said system including a plurality of secondary chambers disposed internally of said chuck body and each being associated with one of said jaw carriers, each of said secondary chambers having secondary piston means slidably disposed therein and coacting with a respective jaw carrier for causing corresponding movement thereof when said secondary piston means is slidably moved within its respective secondary chamber; said system further including passageway means providing fluid for communication between each of said secondary chambers and said primary chamber for causing movement of said secondary pistons and said jaw carriers in response to displacement of said first piston means.",
    "12. A chuck construction according to claim 11, wherein said closed fluid system is of the double-acting type and includes pressure fluid compartments disposed on opposite sides of said first-mentioned piston means and on opposite sides of each of said secondary piston means for permitting movement of said jaw carriers in opposite directions in response to movement of said first-mentioned piston means in opposite directions.",
    "13. In a chuck construction having a chuck body and a plurality of jaw carriers slidably mounted on said chuck body and movable relative thereto toward and away from a workpiece engaging position, said jaw carriers each having at least a radial component of motion relative to the longitudinal axis of said chuck construction, and actuator means for causing movement of said jaw carriers relative to said chuck body, the improvement wherein said actuator means comprises: first wall means defining a substantially closed primary chamber adapted to have a substantially imcompressible pressure fluid disposed therein; primary piston means slidably disposed in said primary chamber for effecting pressurization of said pressure fluid; second wall means defining a substantially closed secondary chamber adapted to have said substantially incompressible pressure fluid disposed therein; second piston means slidably disposed in said secondary chamber and coacting with at least one of said jaw carriers for moving same relative to said chuck body; passageway means providing fluid communication between said primary and secondary chambers, whereby movement of said primary piston means in one direction within saId primary chamber causes pressurization and transfer of fluid from said primary to said secondary chamber for causing movement of said second piston means, which movement of said second piston means in turn causes a corresponding movement of said at least one jaw carrier; and mechanical means drivingly interconnecting said jaw carriers for causing all of said jaw carriers to be simultaneously moved through substantially equal distances in response to movement of said secondary piston means; said mechanical means including a gear member concentric with and rotatably supported on said chuck body, said second piston means having a gear rack portion provided thereon and disposed in meshing engagement with said gear member, and each of said jaw carriers having a gear rack portion associated therewith and disposed in meshing engagement with said gear member."
  ],
  "cpc": [
    "B23B 31/16066",
    "Y10T 279/1291",
    "Y10T 279/19",
    "Y10T 279/25"
  ],
  "assignees": [
    "BUCK TOOL CO"
  ],
  "filing_date": "1972-10-16",
  "publication_date": "1974-06-04",
  "grant_date": "1974-06-04",
  "priority_date": "1972-10-16",
  "application_number": "US-29763272-A",
  "family_id": "23147115",
  "citations": [
    "US1815562A",
    "US2587893A",
    "US3076662A",
    "US3096988A"
  ]
}