Double cardan universal joint with improved centering means

Claim 2

In a double Cardan universal joint having first and second yoke members, centering means comprising a ball having a center midway between said yoke members fixedly carried by said first yoke member, a sleeve enclosing said ball fixedly carried by said second yoke member, ball seat means slidably disposed in said sleeve, a reaction member disposed in said sleeve, a spring disposed in said sleeve, said spring being compressed between said ball seat means and said reaction member and biasing said ball seat means into engagement with said ball, and means for maintaining said reaction member at a constant distance from said center and perpendicular to the axis of said ball seat means irrespective of the operating angle of the joint whereby said spring biases said ball seat means into engagement with said ball with a substantially constant force.

Claim 3

In a double Cardan universal joint having first and second yoke members, centering means as defined in claim 1 wherein said last named means comprises means mounting said reaction member on said first yoke member for pivoting movement about said center and piloting means maintaining said reaction member coaxial with the longitudinal axis of said second yoke member.

Claim 4

In a double Cardan universal joint having first and second yoke members, centering means as defined in claim 1 wherein said sleeve has an external partispherical surface and further having a seal secured to said first yoke member and including a flexible, rubber-like annulus biased into sealing engagement with said external partispherical surface of said sleeve at the maximum diameter thereof when the longitudinal axes of said first and second yoke members are aligned whereby said flexible, rubber-like annulus is substantially removed from the frictional heat generated by the ball and the ball seat during joint operation and is required to expand and contract its interior opening a minimum amount responsive to joint angulation.

Claim 5

In a double Cardan universal joint having first and second yoke members, centering means comprising a hollow ball having a center midway between said yoke members fixedly carried by said first yoke member with said center lying on the longitudinal axis of said first yoke member, a sleeve enclosing said ball fixedly carried by said second yoke member, ball seat means slidably disposed in said sleeve in a coaxial relationship with the longitudinal axis of said second yoke member, a reaction member disposed in said sleeve and slidably piloted on an internal surface of said sleeve, said internal surface being coaxially disposed with respect to the longitudinal axis of said second yoke member, a ball stud having a ball portion in bearing engagement with an interior surface of said hollow ball and a stud portion secured to said reaction member, and a spring having linearly variable load deflection characteristics compressed between said ball seat means and said reaction member and biasing said ball seat means into engagement with said ball, said ball stud and said internal surface of said sleeve maintaining said reaction member at a constant distance from said center and coaxial with said longitudinal axis of said second yoke member irrespective of the operating angle of the joint whereby said spring biases said ball seat means into engagement with said ball with a substantially constant force.

Claim 6

In a double Cardan universal joint having first and second yoke members, centering means comprising a hollow ball having a center midway between said yoke members fixedly carried by said first yoke member with said center lying on the longitudinal axis of said first yoke member, a sleeve enclosing said ball fixedly carried by said second yoke member, ball seat means slidably disposed in said sleeve in a coaxial relationship with the longitudinal axis of said second yoke member, a reaction member disposed in said sleeve and slidably piloted on an internal surface of said sleeve, said internal surface being coaxially disposed with respect to the longitudinal axis of said second yoke member, a ball stud having a ball portion in bearing engagement with an interior surface of said hollow ball and a stud portion secured to said reaction member, and a spring having linearly variable load deflection characteristics compressed between said ball seat means and said reaction member and biasing said ball seat means into engagement with said ball, said ball stud and said internal surface of said sleeve maintaining said reaction member at a constant distance from said center and coaxial with said longitudinal axis of said second yoke member irrespective of the operating angle of the joint whereby said spring biases said ball seat means into engagement with said ball with a substantially constant force.

Claim 7

In a double Cardan universal joint having first and second yoke members, centering means as defined in claim 4 wherein said sleeve has an external partispherical surface and further having a seal secured to said first yoke member and including a flexible, rubber-like annulus biased into sealing engagement with said external partispherical surface of said sleeve at the maximum diameter thereof when the longitudinal axes of said first and second yoke members are aligned whereby said flexible, rubber-like annulus is substantially removed from the frictional heat generated by the ball and the ball seat during joint operation and is required to expand and contract its interior opening a minimum amount responsive to joint angulation.