Abstract: The tightening screw of the invention comprises a screw member forming a female threads or male threads in the shaft core part, a flange ring fitted to the outer periphery of the screw member to contact with the object to be tightened, an operating ring for feeding a rotational force by fitting oppositely to the flange ring on the outer periphery of the screw member, and a torque transmitting member interspaced between the screw member and operating ring for transmitting the rotational force of the operating ring to the screw member. The torque transmitting member comprises a reduction mechanism for transmitting the rotational force of the operating ring to the screw member by reducing the speed, and a unidirectional torque limiter for cutting off transmission of torque in the tightening direction of the screw member to the object to be tightened at a specific load.

Abstract: A non-impact keyless chuck suitable for use with manual or powered drivers is disclosed. The chuck comprises a body which carries a rotatable split nut having a relatively fine thread and a plurality of slidable jaws, which may be identical, driven by the rotatable nut. An anti-friction bearing is disposed between the rotatable nut and a bearing thrust ring mounted on the body. A clutch or torque limiting mechanism is provided to limit the tightening torque to a predetermined value while the loosening torque may be limited or unlimited. The front sleeve, and rear sleeve, if used, may be formed from a structural plastic to reduce manufacturing costs. A relatively soft elastomeric grip boot may be placed on the front sleeve to improve the grip and temporarily restrain and center the tool during chuck tightening or loosening operations. A relatively soft elastomeric grip boot may also be placed on the rear sleeve, if used.

Abstract: A tightening screw in which a rotating ring is rotatably held on a flange ring, a screw member having female threads in the same pitch as the male threads of the bolt to be fitted, with the female thread diameter formed larger than the male thread diameter, is rotably held eccentrically so that some of the female threads of the screw member may be engaged with the male threads preliminarily, and the flange is fixed at the time of tightening so that the rotating ring may revolve the screw member, and thereby the decelerated rotation created in the screw member produces a large tightening force to increase the torque.

Abstract: A three-jaw chuck is provided with a unitary nut rotatably mounted relative to the body and a retaining member located so as to contact a portion of the unitary nut to prevent axial movement of the nut in the forward direction. The nut may include a first portion of a first outside diameter and a second portion extending axially outward from the first portion with an outside diameter less than the first outside diameter. A sleeve retaining snap ring may be provided engaging the sleeve for retaining the sleeve on the body.

Abstract: Chuck for use with a manual or powered driver including a nut rotatably mounted on the chuck body and in engagement with the threads of the chuck jaws. The chuck includes a self-contained anti-friction bearing assembly disposed between the nut and a thrust ring, as well as a generally cylindrical front sleeve member in driving engagement with the nut and overlying a nose section of the body of the chuck so that when the front sleeve member is rotated with respect to the body member, the jaws will be moved thereby. The chuck also includes a rust resistant decorative nosepiece as well as an improved nut retainer member.

Abstract: A chuck for use with a manual or powered driver having a rotatable drive shaft including a primary tightening mechanism utilizing a three-jaw assembly actuated by a nut or tightening ring and a supplemental tightening mechanism. The supplemental tightening mechanism includes a camming portion defining a tightening cam profile and a release cam profile. The supplemental tightening mechanism further includes a plurality of lever bars, one end of each of the lever bars forming a cam follower and the other end of each of the lever bars operatively associated with the nut so that when the supplemental tightening mechanism is actuated in a tightening direction, the lever bars will force the nut forward to produce an enhanced tightening force on the tool through the jaws, and when the rear sleeve is rotated in a release direction, the force applied to the nut by the lever bars will be released.

Abstract: A plastic grip boot for a metal part of a chuck, typically a keyless chuck, is disclosed. The grip boot is insert molded to a rotatable metal part of a chuck, the metal part extending under the grip boot for the axial length of the grip boot which is normally gripped by the user in order to provide support to the grip boot. During molding, the plastic preferably flows into surface features of the metal part to help secure the grip boot to the metal part. The grip boot improves user grip of the metal part during operation of the chuck to adjust the spacing of the chuck jaws.