Pinless impact universal joint

A universal joint, for use with an impact wrench to co-rotationally couple a driver to a fastener member for transferring impact-type rotational forces therebetween, the universal joint comprising:

• a driven member having first and second ends, with one of a ball member and a ball receiving cavity disposed at said first end;
• a driving member having first and a second ends, with a ball member disposed at said first end, and said driving member further having a driver receiving member disposed at said second end for engaging a drive piece of a driver;
• said ball receiving cavity having a base;
• said ball member having a head which is disposed in said ball receiving cavity and co-rotationally coupled with said ball receiving cavity for transferring rotational forces therebetween;
• a compression washer formed of a resilient polymer material, said compression washer disposed between said head of said ball member and said base of said cavity, adjacent to said base of said cavity;
• a tension washer formed of a wear resistant polymer material disposed between said head of said ball member and said compression washer, adjacent to said head of said ball member;
• wherein said compression washer, in response to being pressed inward toward said base of said cavity, exerts a preload force against said tension washer and the head of said ball member;
• and
• an engagement device disposed on said second end of said driven member for engaging a fastening member.

A method for transferring impact-type rotational forces into a driving member, through an angle and then to a driven member, the method comprising the steps of:

• rotating the driving member, having first and second ends and having a driver receiving member disposed at the first end and a ball receiving cavity having a base disposed at the second end, using a driver;
• rotating the driven member, having first and second ends and having a ball member disposed at the first end, the ball member having a head and the ball member disposed in the ball receiving cavity, the ball member co-rotationally coupled with the ball receiving cavity, the driven member being driven by the driving member;
• disposing a polymer member having a first portion with a wear resistant surface disposed directly adjacent to the head of the ball member, and disposing a second resilient portion between the first portion and the base of cavity;
• exerting a preload force against the head of the ball member in response to the polymer member being disposed between the head of the ball member and the base of the cavity, and being compressed therebetween, wherein the polymer member presses the wear resistant surface of the first portion against the head of the ball member;
• and
• rotating a fastener using a fastening member engagement device disposed on the second end of the driven member.

A method for transferring impact-type rotational forces into a driving member, through an angle and to a driven member, the method comprising the steps of:

• providing a driving member and a driven member, one having a ball receiving cavity and the other having a ball member for disposing within the cavity to co-rotationally couple the driving and the driven members together for transferring rotational forces therebetween, and further providing a polymer member, the polymer member having a first portion with a wear resistant surface adjacent the ball member and a second portion between the first portion and the base of the ball receiving cavity;
• co-rotationally coupling the driving and the driven members together, with the ball member disposed within the ball receiving cavity for transferring the rotational forces therebetween, and the polymer member being disposed in the cavity inward of the ball member, between the driving and the driven members, and adjacent to the base of the ball receiving cavity;
• angularly displacing the driving member relative to the driver member, to dispose the driven member at the angle relative to the driving member;
• rotating the driving member to co-rotate and transfer the rotational forces to the driven member;
• wherein co-rotating the driving member and the driven member, with the driven member disposed at the angle to the driving member, and transferring the rotational forces therebetween moves the ball member within the cavity and presses the ball member against the polymer member;
• and
• wherein the polymer member continuously applies preload forces toward the ball member in response to being squeezed between the ball and the base of the ball receiving cavity.