A telescopic shaft is provided. The telescopic shaft includes a first shaft including a first coupler having an inner circumferential surface including an external straight groove and an external inclination groove formed thereon, the external straight groove having a semi-circular cross section and being formed in parallel to a rotation axis and the external inclination groove having a semi-circular cross section, being inclined with respect to the external straight groove at a predetermined angle, and being shaped like a spiral, a second shaft including a second coupler inserted into the first coupler and having an outer circumferential surface including an internal straight groove and an internal inclination groove formed thereon, the internal straight groove having a semi-circular cross section and corresponding to the external straight groove and the internal inclination groove having a semi-circular cross section, being inclined in an opposite direction to the external inclination groove at a predetermined angle with respect to the internal straight groove, and being shaped like a spiral, and a plurality of balls arranged in a line in an axial direction between the external straight groove and the internal straight groove, one ball being arranged between the external inclination groove and the internal inclination groove, wherein the first shaft and the second shaft are coupled to extend and retract in an axial direction, thereby preventing play from occurring in a circumferential direction and preventing separation of balls.

A telescopic shaft is provided. The telescopic shaft includes a first shaft including a first coupler having an inner circumferential surface including an external straight groove and an external inclination groove formed thereon, the external straight groove having a semi-circular cross section and being formed in parallel to a rotation axis and the external inclination groove having a semi-circular cross section, being inclined with respect to the external straight groove at a predetermined angle, and being shaped like a spiral, a second shaft including a second coupler inserted into the first coupler and having an outer circumferential surface including an internal straight groove and an internal inclination groove formed thereon, the internal straight groove having a semi-circular cross section and corresponding to the external straight groove and the internal inclination groove having a semi-circular cross section, being inclined in an opposite direction to the external inclination groove at a predetermined angle with respect to the internal straight groove, and being shaped like a spiral, and a plurality of balls arranged in a line in an axial direction between the external straight groove and the internal straight groove, one ball being arranged between the external inclination groove and the internal inclination groove, wherein the first shaft and the second shaft are coupled to extend and retract in an axial direction, thereby preventing play from occurring in a circumferential direction and preventing separation of balls.

A flexure joint apparatus includes a first fixing unit, at least one first flexure extending from the first fixing unit, and a connection member having a first head elastically supported by the at least one first flexure.

The present invention provides a wide angle joint including: a pair of yoke shafts mounted on opposite sides thereof to transmit power from the one side to the opposite side, each yoke shaft having a ball end portion provided on a first yoke part to which a spider is coupled; a plate having a large-diameter part formed in the middle thereof and protruding parts protruding from the large-diameter part in the opposite axial directions while being reduced in a radially inward direction, wherein the protruding parts have insertion recesses into which the ball end portions of the yoke shafts are inserted, and the large-diameter part is faulted to have different widths in radial directions from the central portion thereof; and a pair of coupling yokes, each of which has a second yoke part connected with the first yoke part through the spider and a support recess into which the large-diameter part of the plate is inserted.

The present invention provides a wide angle joint including: a pair of yoke shafts mounted on opposite sides thereof to transmit power from the one side to the opposite side, each yoke shaft having a ball end portion provided on a first yoke part to which a spider is coupled; a plate having a large-diameter part formed in the middle thereof and protruding parts protruding from the large-diameter part in the opposite axial directions while being reduced in a radially inward direction, wherein the protruding parts have insertion recesses into which the ball end portions of the yoke shafts are inserted, and the large-diameter part is faulted to have different widths in radial directions from the central portion thereof; and a pair of coupling yokes, each of which has a second yoke part connected with the first yoke part through the spider and a support recess into which the large-diameter part of the plate is inserted.

A roller bearing for a pod joint comprising an inner race, an outer ring assembly, a race that runs along a bell section and is disposed on the outer surface of the outer ring assembly, a plurality of rolling elements, wherein the plurality of rolling elements are disposed between the inner race and the outer ring assembly and are formed as rollers, and a cage assembly, wherein the rolling elements are disposed in the cage assembly, wherein the cage assembly is formed as a central cage, wherein the rollers pass through the central cage in a middle area, and the running areas thereof project outward from both sides of the central cage.

A roller bearing for a pod joint comprising an inner race, an outer ring assembly, a race that runs along a bell section and is disposed on the outer surface of the outer ring assembly, a plurality of rolling elements, wherein the plurality of rolling elements are disposed between the inner race and the outer ring assembly and are formed as rollers, and a cage assembly, wherein the rolling elements are disposed in the cage assembly, wherein the cage assembly is formed as a central cage, wherein the rollers pass through the central cage in a middle area, and the running areas thereof project outward from both sides of the central cage.

Various drop head coupling assemblies are described. The coupling assemblies enable a drop head tool typically used in drain cleaning operations to be releasably engaged with a drain cleaning cable. The coupling assemblies enable the drop head tool to undergo a wide range of motion relative to the drain cleaning cable, particularly during rotation of the cable and drop head.

An apparatus for correcting an imbalance in a rotating shaft along with a method for correcting the imbalance in a rotating shaft is identified. The apparatus includes a joint assembly having a first joint member that is drivingly connected to a second joint member by one or more third joint members. At least a portion of a first shaft may be drivingly connected to at least a portion of the first joint member and at least a portion of a second shaft may be drivingly connected to at least a portion of a second end portion of the second join member. A boot can may be connected to at least a portion of a first end portion of the second joint member. One or more balancing elements may then be connected to at least a portion of the boot can and/or the second joint member of the joint assembly.

A boot includes a large-diameter tubular portion, a small-diameter tubular portion, and a bellows portion. The large-diameter tubular portion includes a fastening groove into which a fastening member is fitted, an opening end to which the bellows portion is coupled and into which an outer case is inserted, at least one seal lip having an annular shape and protruding from an inner circumferential surface of the large-diameter tubular portion at the position where the fastening groove is projected to the inside in the radial direction, so as to be continuous over the entire circumference, and a protrusion protruding from the inner circumferential surface on the opening end side with respect to the seal lip so as to be provided over the entire circumference. A height of the protrusion is set to be smaller than a height of the seal lip.