Adjustable torque controlled tool holder

Claim 2

A rotary tool holder, comprising a rotary driving member, a first driven member means connecting said first driven member to said driving member for rotation thereby, a second driven member adapted to hold a tool, means for releasably coupling said second driven member to said first driven member for rotation thereby about a common axis, including at least one coupling element mounted on one of said driven members for limited movement into and out of driving engagement with the other of said driven members, resilient means normally forcing said coupling element into its operative position, means for camming said element into an inoperative position out of driving engagement with said other driven member, whenever the torque transmitted from said first to said second driven member exceeds a predetermined value, and means operable automatically and releasably for removing the force of the resilient means from the coupling element to allow said element to remain in its inoperative position each time it is moved thereto.

Claim 3

A rotary tool holder as defined in claim 1, including means mounting said retaining means for operation, when said first driven member is rotated in one direction, and for effecting release of said retaining means and returning said element to its operative position, when said first driven member iS rotated in the opposite direction.

Claim 4

A rotary tool holder as defined in claim 1, wherein said coupling element is movable radially of said axis between its operative and inoperative positions, said resilient means comprises an operating member reciprocable parallel to said axis, and a spring normally urging said operating member against said element to hold said element resiliently in its operative position, second camming means formed on the confronting surfaces of said element and said operating member and urging said operating member to inoperative position, when said coupling element is moved to its inoperative position by the first-named camming means, and said retaining means includes means interposed between said operating member and said spring releasably to remove the force of said spring from said operating member each time said operating member is moved to its inoperative position.

Claim 5

A rotary tool holder as defined in claim 1, wherein said resilient means comprises a spring-loaded ring reciprocable axially on said one driven member, and normally urging said element resiliently to its operative position, said retaining means comprises a detent mounted on said ring for movement on said one driven member, and projecting into a recess in said one driven member, one side of said recess is inclined to the direction of reciprocation of said ring and has therein a plurality of spaced notches, and said detent is seated in one of said notches, when said coupling element is in its operative position, and is seated releasably in another of said notches to hold the detent and said ring in retracted positions on said one driven member, when said coupling element is shifted to its inoperative position.

Claim 6

A rotary tool holder, comprising a rotary driving member, a driven member, means for transmitting the rotation of said driving member to said driven member, a third member for holding a tool, means for releasably coupling said third member to said driven member for rotation thereby about a common axis, including a plurality of coupling members mounted on one of the two releasably coupled parts for limited movement into and out of driving engagement in a plurality of cooperating recesses in the other of said two releasably coupled parts, resilient means normally forcing said coupling members resiliently into driving engagement in said recesses, means on said other part for camming said coupling members out of said recesses and into inoperative positions when the torque transmitted from said driven member to said third member exceeds a predetermined amount, thereby to allow rotation of said driven member relative to said third member, and means for releasably removing the force of said resilient means from said coupling members each time the transmitted torque exceeds said predetermined amount.

Claim 7

A rotary tool holder, comprising a rotary driving member, a driven member, means for transmitting the rotation of said driving member to said driven member, a third member for holding a tool, means for releasably coupling said third member to said driven member for rotation thereby about a common axis, including a plurality of coupling members mounted on one of the two releasably coupled parts for limited movement into and out of driving engagement in a plurality of cooperating recesses in the other of said two releasably coupled parts, resilient means normally forcing said coupling members resiliently into driving engagement in said recesses, means on said other part for camming said coupling members out of said recesses and into inoperative positions when the torque transmitted from said driven member to said third member exceeds a predetermined amount, thereby to allow rotation of said driven member relative to said third member, and means for releasably removing the force of said resilient means from said coupling members each time the transmitted torque exceeds said predetermined amount.

Claim 8

A rotary tool holder as defined in claim 5, wherein said driven member is a sleeve surrounding one end of said third member, said one end of said third member is cylindrical and has said recesses formed in its peripheral surface, said coupling members are movably mounted in a plurality of radial holes in said sleeve, a spring-loaded ring is axially slidable on said sleeve, and has an internal conical surface engaging said coupling members resiliently to hold them seated in said recesses, whereby when said torque exceeds said predetermined amount, said coupling members are forced out of said recesses onto said peripheral surface of said third member, and radially outwardly against said conical surface with sufficient force to shift said ring axially in one direction on said sleeve, and said force removing means comprises means responsive to the movement of said ring in said one direction automatically to retain said ring releasably in any one of a plurality of different inactive positions on said sleeve, depending upon the axial distance said ring is moved in said one direction by said coupling members.

Claim 9

A rotary tool as defined in claim 6, wherein said force removing means comprises a second ring slidable on said sleeve between the first-named ring and its associated spring, a ball detent secured at one side in a recess in one of the two confronting surfaces on said second ring and said sleeve, respectively, and projecting into a second recess in the other of said confronting surfaces, said second recess being bounded along one side thereof by a stepped surface inclined to the axis of said sleeve, and having therein a plurality of spaced notches engageable with said detent to secure said second ring in one of a plurality of inactive positions in which said second ring releasably withholds the force of said spring from said first-named ring.

Claim 10

A rotary tool as defined in claim 7, wherein a pair of said detents are secured in recesses formed in the inner peripheral surface of said second ring at diametrally opposite sides thereof, and a pair of said second recesses are formed in the outer peripheral surface of said sleeve at diametrically opposite sides thereof to register with said detents.

Claim 11

A rotary tool as defined in claim 5, wherein said driving member is a shaft, which is adapted to be secured to the spindle of a machine, said driven member is a sleeve axially slidable on said shaft between first and second limit positions, a tension spring is secured at opposite ends thereof to said shaft and said sleeve, respectively, to resist axial movement of said sleeve downwardly on said shaft, and normally urging said sleeve to one of its limit positions, and means is interposed between said shaft and said spring for adjusting the tension in said spring.

Claim 12

A rotary tool as defined in claim 6, wherein a collar surrounds said sleeve adjacent one end thereof, a plurality of axially-extending compression springs are equi-angularly spaced around the outside of said sleeve, and said springs are seated at one end in recesses in said collar and at their opposite ends are operatively connected to said ring resiliently to urge the latter towards its active position against said coupling elements.