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US 4,041,729 AGranted
Overland coupling device
AssigneeOtto Bilz, Werkzeugfabrik GmbH & Co.
InventorReiner Bilz
Life of this patent
Estimating the term…
Abstract
An overload coupling device has a drive shank, a drive sleeve for driving the drive shank, a closure sleeve surrounding the drive sleeve and a thrust ring. The shank and sleeves is provided with apertures containing balls and the thrust ring is urged by a spring to normally hold the balls in the apertures of the drive shank and drive sleeve to provide a driving connection therebetween but allows the balls to slide in the apertures of the drive sleeve and into the apertures of the closure sleeve to release the driving connection in the event of torque overload.
Claims29
An overload coupling device for thread-cutter - chucks, quick-change inserts therefor, and the like, said device comprising a cylindrical sleeve loadable with the rotational drive moment;
- a drive shank drivable by means of the drive sleeve and held coaxially and rotatably within the latter, said shank having a mounting for the rotation-fast retention of a tap drill;
- a torque coupling with adjustable tripping torque seated in the force-transmission parts between drive sleeve and drive shank, said coupling being formed as spring-loaded ball-pocket coupling with at least one coupling ball, the drive sleeve being axially non-displaceably held on the drive shank and provided with at least one opening open in the axial direction on one axial end face and serving for the reception of said coupling ball, the angular width of said opening being at least as great as the coupling ball diameter, the drive shank in the axial region of the opening comprises a ball-pocket of a diameter smaller than the diameter of the coupling ball for the reception of the coupling balls, said opening being formed as cage slots which are inwardly and outwardly open in the radial direction and the axial extent of which is less than the coupling ball diameter, the cage slots being inclined toward the working drive direction of the drive sleeve, the ball-pockets being arranged on the outer peripheral surface of the drive shank facing the drive sleeve;
- a cylindrical closure sleeve coaxially enclosing the drive sleeve and the drive shank being axially non-displaceably held on the drive sleeve and possessing in the axial region of the cage slots in the interior an annular groove the bottom of which extends at a radial distance corresponding at least to the coupling ball diameter from the peripheral surface of the drive shank;
- and in the annular space between drive shank and closure sleeve on the axial side of the coupling balls remote from the bottom of the cage slots a thrust ring which is pressable axially in the direction towards the cage slots and against the coupling balls by means of thrust springs adjustably supported on the closure sleeve the two mutually opposite walls of each cage slot considered in a diametric plane at right angles to the longitudinal central axis each extending along a secant of the peripheral circle of the drive shank and of the drive sleeve and parallel to and with spacing from a diameter of said peripheral circle.
1 more element
A coupling comprising:
- a driven member rotatable in a predetermined forward rotational sense about a rotation axis and formed with at least one radially outwardly open pocket;
- a driving member having a portion radially surrounding said driven member at said pocket and rotatable about said axis relative to said driven member while being axially nondisplaceable relative to said driven member, said driving member having at least one axially open slot radially alignable with said pocket and having a predetermined axial depth;
- a sleeve surrounding said driving member at said pocket;
- a ball in said slot and having a diameter greater than said predetermined axial depth, said ball being radially displaceable between a coupling position engaged in said slot and in said pocket and a decoupling position engaged in said slot and with said sleeve and clear of said pocket, whereby said members are rotationally coupled with said ball in said coupled position and decoupled with said ball in said decoupled position;
- a thrust ring axially aligned with said portion and having a frustoconical end surface tapered axially away from said driving member and engageable with said ball at least in said coupled position;
- and
- spring means biasing said thrust ring axially for urging said ball radially with said frustoconical surface into said pocket and hence into said coupled position with a predetermined spring force.
4 more elements
A coupling comprising:
- a driven shank rotatable in a predetermined forward rotational sense about a rotation axis and formed with at least one radially outwardly open pocket;
- mounting means on said driven shank for holding a rotary tool at said axis;
- a drive sleeve radially surrounding said driven shank at said pocket and rotatable about said axis relative to said driven shank while being axially nondisplaceable relative thereto, said drive sleeve being formed with at least one axially open slot radially alignable with said pocket and having a base surface lying substantially in a plane perpendicular to said axis and relative to said forward rotational sense a leading axially extending flank and a trailing axially extending flank, said leading flank being inclined into said forward rotational sense and having relative thereto an inner leading edge and an outer trailing edge, whereby rotation of said drive sleeve about said axis in a reverse rotational sense opposite to said forward rotationl sense cams said ball radially inwardly with said leading edge, said slot having a predetermined axial depth;
- a coupling ball in said slot having a diameter greater than said axial depth and being displaceable in said slot between a radially inner coupling position engaged in said pocket and a radially outer decoupling position clear of said pocket, whereby said sleeve and said shank are rotationally coupled with said ball in said coupled position and are decoupled with said ball in said decoupled position;
- a thrust ring axially aligned with said sleeve and having an end axially engageable with said ball, said end being subdivided into a radially inner frustoconical surface tapered away from said drive sleeve and engageable with said ball only in said coupled position and extending radially outwardly from said inner surface and outer surface substantially parallel to said base surface and engageable with said ball only in said decoupled position;
- and
- spring means biasing said thrust ring axially for pressing said ball in said coupled position radially with said frustoconical inner surface into said pocket and in said decoupled position for pressing said ball with said outer surface against said base surface of said slot.
4 more elements
Dependencies are inferred from the claim text.